CA2227796A1 - Method of electrostatically printing image-enhancing particles and said particles - Google Patents
Method of electrostatically printing image-enhancing particles and said particles Download PDFInfo
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- CA2227796A1 CA2227796A1 CA002227796A CA2227796A CA2227796A1 CA 2227796 A1 CA2227796 A1 CA 2227796A1 CA 002227796 A CA002227796 A CA 002227796A CA 2227796 A CA2227796 A CA 2227796A CA 2227796 A1 CA2227796 A1 CA 2227796A1
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- enhancing
- toner
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G13/00—Electrographic processes using a charge pattern
- G03G13/06—Developing
- G03G13/08—Developing using a solid developer, e.g. powder developer
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G9/00—Developers
- G03G9/08—Developers with toner particles
- G03G9/097—Plasticisers; Charge controlling agents
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G13/00—Electrographic processes using a charge pattern
- G03G13/01—Electrographic processes using a charge pattern for multicoloured copies
- G03G13/013—Electrographic processes using a charge pattern for multicoloured copies characterised by the developing step, e.g. the properties of the colour developers
- G03G13/0139—Electrographic processes using a charge pattern for multicoloured copies characterised by the developing step, e.g. the properties of the colour developers developing using a step for clear toner deposition, e.g. for regulating gloss or supplying protective coatings
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G9/00—Developers
- G03G9/08—Developers with toner particles
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G9/00—Developers
- G03G9/08—Developers with toner particles
- G03G9/09—Colouring agents for toner particles
- G03G9/0926—Colouring agents for toner particles characterised by physical or chemical properties
Abstract
The present invention relates to a method of electrostatically printing image-enhancing particles comprising the steps of: providing a first image on a substrate wherein the first image is formed from a composition comprising: (I) optionally, electrostatically printable image-enhancing particles, comprising:
(A) an image-enhancing particle; and (B) an electrostatically chargeable material attached to an exterior surface of the image-enhancing particle, wherein the electrostatically chargeable material comprises: (i) an electrostatically chargeable polymeric material, and (ii) optionally a charge controlling compound; (II) optionally toner particles; optionally providing one or more subsequent image(s) in registration with said first image and fusing the deposition image(s). The invention also relates to novel electrostatically printable image-enhancing particles.
(A) an image-enhancing particle; and (B) an electrostatically chargeable material attached to an exterior surface of the image-enhancing particle, wherein the electrostatically chargeable material comprises: (i) an electrostatically chargeable polymeric material, and (ii) optionally a charge controlling compound; (II) optionally toner particles; optionally providing one or more subsequent image(s) in registration with said first image and fusing the deposition image(s). The invention also relates to novel electrostatically printable image-enhancing particles.
Description
METEOD OF ELECTROSTATICALLY PRINTING
IM~GE-ENHANCING PARTICLES AND SAID PARTICLES
FIELD OF THE rNVENTION
The present invention relates to a novel method of producing graphics employing image-~nh~nl ing particles electrostatically. The invention also relates to novel electrostatically printable image-çnh~nring particles.
BACKGROUND OF THE INVENTION
Decorative graphics for automotive trim and orn~m~nt~tion have been conventionally produced by screen printing an ink onto an adhesive coated film.
Image-enhancing particles are often incorporated into these printing inks to provide an interesting visual appearance such as sparkle, color flop, iri(lesc~n~e or luster.
Representative examples of image-enhancing particles include metallic flake and spherical particles, such as ~ mimlm flake or ~lllmimlm spheres, pearlescent flake pigments such as metallic oxide coated mica, metallic oxide coated glass flake, and metallic oxide coated polyester flake. These image-~nh~n~ing particles are usually in the 1-200 microns tli~m-o.tf!r size range. Particles in the range of about 1-20 microns generally exhibit more of a lustrous appearance, while particles larger than 20 microns generally have an increasing amount of a sparkle appearance, that increases as the particle size increases. Some image-çnh~nçing particles are more functional in nature.
For example, phosphors can be used to make an electrolllminesc~nt lamp or metallic coated glass beads can be used to provide ~ lul~llection.
However, it would be desirable to replace analog printing methods such as screen printing with a digital printing method in order to reduce cycle times and produce short runs economically. In addition, most digital printing processes elimin~te the need for printing plates and significantly reduce job set-up and changeover times.
W O 97/08590 PCT~US96/13178 --2--While digital color printing is well known in the graphics industry, digitally printing the breadth of image-enhancing particles used in the screen printing industry has largely been ignored. This may be due to the particle size and/or the conductivity of many image-enhancing particles such as, for example, ~ mimlm flake. The use of a particular type of image-enhancing particle, ~ ", oxide coated flake-form inorganic crystal, in colored toner formulations is taught in Japanese Patent Kokai No. Sho 62[1987]-100771. Kokai No. Hei 1~1989]-112254 further teaches use of the above mentioned flake-form particles first coated with a black tit~nillm oxide layer in toner formulations that are preferably colored. However, a wider range of decorative or 10 functional effects are desired requiring a much wider range of image-enhancing particles.
Known methods of l~tili7ing image-~.nh~n~ing particles in solid toners involve compounding a separate batch oftoner CO..I~ g image-Pnh~n~ing particles for eachcolor in which an image-Pnh~n-~.in~ effect is desired. For example, green toner may be compounded with metallic flake to produce a metallic green color. Likewise, if ametallic red was desired, metallic flakes would be compounded with red toner, etc.
Thus, for every dirr~;lell~ color and concentration of image-P.nh~n~.ing particles, a separate batch of toner compounded with image-~nh~n~ing particle was required.
Making small batches of toner and image-~nh~n-~in~ particles is a costly process with 20 no economies of scale. Therefore, it would be further desirable to achieve m~ ipl(?
color image-.-.nh~n~.ing effects without having to produce multiple batches of color toner co..l~ il~ image-enh~n~ing particles.
Because print resolution is largely determined by the particle size of toner andmany desirable image-enh~n~ing effects require particle sizes in excess of convention~l higher resolution toner particles sizes, it would be still further desirable to print "
digitally larger image-enh~ncing particles without sacrificing overall image resolution.
SIJMMARY OF THE INVENTION
The present invention, which overcomes the difficulties of known pl in~ g methods, employs an image-~nh~ncing particle at least partially coated with an electrostatically chargeable material free of dyes and pigment~ according to theS restrictions set forth herein. This electrostatically chargeable material may be, for example, a toner material which is free of dyes and pigments. These modified image-~nh~n~ing particles of the invention are referred to herein also as "electrostatically printable image-~nh~nçing particles."
The electrostatically printable image-enh~nring particles of the invention can be 10 used in a number of methods. In one such method, electrophotography, the electrostatically printable image-enh~n-.ing particles can be added to any colored toner (preferably Ll~ls~a~nl or tr~n~ cent colored toner so as not to hide the image-enh~ncing effect) and printed as a dual component mixture or can be applied by itself in a first stage, for example, in a multi-station printer and subsequent colors (in the form 15 of colored toner, for ~x~mple) applied in registration over the image-f.nh~nr.ing particles in the later print stations.
In addition to electrophotographic printing methods, these image-~nh~ncing particles may also be used in other plillLiilg methods employing solid toners such as so-called direct printing. An example of a direct toner printer is the TonerJet~ made by 20 Array Printers in Sweden. In direct printing, the substrate passed through anelectrostatic field which attracts toner to the substrate surface. But the toner must first pass through an array of microscopically fine apertures, each surrounded by a ring electrode. Dots are formed directly on the substrate by charging the ring electrodes to add to the attraction of the substrate and thereby release "jets" of toner towards the 25 substrate. Once in place, these dots of toner are fused in place and the apertures are cleaned in preparation for printing the next line.
For multi-station printers, a plc;rell~;d method of creating an çnh~nced appearance is to apply the amount of image-rnh~nr.ing particles that are desired at the first printing station and to print the desired color in subsequent stations. A common method of creating many colors from only a few primaries is to use cyan, m~grnt~, 5 yellow, and black primaries in what is called a 4-color process. This technique is particularly useful with the current invention and enables one to print many dirre~
colored image-enhancing graphics, without the expense of many diLr~renL developer units or of rl~ning the developer units many times.
We have thus discovered a novel method of printing image-enhancing particles.
10 The method ofthe invention has a number of distinct adv~nt~gç~, in~ iing but not limited to those tii~c~ ed above, when compared to known methods. Our novel method of electrostatically printing image-Pnh~ncin~ particles comprises the steps of:
(a) providing a first image on a substrate via an electrostatic plilllillg meanswherein the first image is formed from a first composition COlll~uliSillg:
(I) optionally, electrostatically plillL~Ic image-enhancing particles, each electrostatically printable image-~nh~nçing particle comprising:
(A) an image-~.nh~n~ing particle; and (B) an electrostatically chargeable material attached to at least a portion of an exterior surface(s) of the image-rnh~nring particle, wl~rein the 20 electrostatically chargeable material is free of dyes and pi m.ont.~ and wherein the electrostatically chargeable material is selected from the group consisting of Ll~n~ cllL materials, tr~n~l~lcP.nt materials, opaque materials, and combinations thereof, wherein the electrostatically chargeable material comprises: (i) an electrostatically chargeable polymeric material, and (ii) optionally a charge controlling 25 compound; wherein no more than 80% of the exterior surface of each image-~nh~nr.in~
particle may have an opaque electrostatically chalgeable material z~tt~hçd thereto;
_S _ (II) optionally toner particles co.-~h~ g a component selected from the group consisting of dyes, pigmP.nt~, and combinations thereof;
wherein at least one of (a)(I) and (a)(II) is present;
(b) optionally providing one or more subsequent image(s) in registration 5 with said first image wherein said subsequent image(s) are independently formed from a subsequent composition, each subsequent composition independently comprising:
(I) optionally, electrostatically printable image-Pnh~nring particles, each electrostatically printable image-Pnh~ncing particle comprising:
(A) an image-P.nh~n~ing particle; and (B) an electrostatically chargeable material attached to at least a portion of an exterior surface(s) of the image-~nh~nr.ing particle, wherein the electrostatically chargeable material is free of dyes and pigments and wherein the electrost~tic~lly chargeable material is selected from the group consisting of transparent materials, tr~n~ cPnt materials, opaque materials, and combinaLions thereof, wherein the electrostatically chargeable material comprises: (i) an electrostatically chargeable polymeric material, and (ii) optionally, a charge controlling compound; wherein no more than 80% of the exterior surface of each image-enhancing particle may have an opaque electrostatically chargeable material attached thereto;
(II) optionally, toner particles col~ g a component selected from the group consisting of dyes, pigmPnt~, and col~ hldLions thereof;
wherein at least one of (b)(I) and (b)(II) is present in each subsequent composition, wherein at least one of said first image and/or said subsequent image(s), if present, are formed from a composition comprising electrostatically printable image-P.nh~n~.ing particles; and (c) fusing the deposited image(s) wherein the deposited image(s) are fused at least after the last deposited image is formed, and optionally, in ~d-lition, after any previous deposited image(s) are formed.
W O 97/08590 PCTrUS96/13178 The present invention also provides the printed substrates prepared according to the method of the invention.
The present invention also provides the above ~ c~ ecl novel electrostatically printable partides, each particle colllpli~ing:
(a) an image-enhancing particle P~ccl~ ing mica particles coated with a layer of black tit~n jllm oxide;
(b) an electrostatically chargeable material ~ ched to at least a portion of an exterior surface(s~ of the image-enh~ncin~ particle, wherein the electrostatically chargeable material is free of dyes and pigm~nt~ and wherein the electrostatically chargeable material is selected from the group con~i~Lillg of transparent materials, tr~n~ c.~nt materials, opaque materials, and coll,bil~aLions thereof, wherein the electrostatically chargeable material comprises: (i) an electrostatically clla~,eable polymeric material, and (ii) optionally, a charge controlling compound; wherein no more than 80% of the exterior surface of each image-enhancing particle may have an opaque electrostatically chargeable material ~ hçd thereto.
One particular printing method useful in the method of the present invention is electrophotography. In eleckophotography~ a latent image is formed on a charged photoconductor by image-wise exposure to a light source such as a laser or a light çmitting diode. The latent image on the photoconductor is then developed with either a single-component or a two-component developer. In either case, the developer is generally metered out onto a rotating sleeve with a perm~n~?ntly aligned m~gnetic core.
In the case of a single-component developer, the developing composition consists of only a m~gnP.tic toner. Because m~gnçtic materials are generally dark in color, single-component developers are mainly used for black and white printing. In order to achieve suitable colors in color printing, two-component developers are used which consist of non-m~gnetic toner(which can therefore be brightly colored) andm~gnetic carrier particles. Typically, tribocharging is used to create opposite electrostatic charges on the toner and magnetic carrier particles which cause the toner to stick to the m~netic carrier. Tribocharging results from the toner and m~gnetic carrier particles rubbing together in the developer unit. The size of the m~gnetic carrier particles relative to the toner particles is generally at least 3 :1.
In either case, single-component or two-component developing, the polarity of the toner particles is opposite to that of the latent image areas on the photoconductor.
In addition, the m~gnit~cle of electrostatic charge holding toner on magnetic carrier particles or the magnetic forces holding a single-component toner on the developer sleeve should not be greater than the electrostatic attractive forces of the latent image areas on the photoconductor. The developer unit is often biased so as to infll-ence the relative polarity and/or m~gnitllde of the latent image areas on the photoconductor.
Once the latent image is developed on the photoconductor, it may be transferred electrostatically to the final substrate, generally by using a corona charging device behind the substrate to attract the toner from the photoconductor to the substrate. In the case of multi-color printing, multiple photoconductors can be used, each developing a color and transferring it to the substrate. Optionally, a single photoconductor can be used with multiple developing stations where after each color is developed it is ~ r~ d first to an intermediate holding member such as an ~cc Im~ tor belt and then to the final substrate after all images have been ~c.cllmlll~ted on the interme~i~te holding member.
After transferring the toner from the photoconductor, residual toner is removed from the photoconductor by means of a brush or flexible scraping blade, residualcharge on the photoconductor is erased and the entire process can be repeated. If the photoconductor is a seamless drum or belt, a longer or continuous image can be formed from multiple revolutions of the photoconductor.
Another type of electrophotography utilizes a so-called tri-level developing scheme. In a tri-level electrophotographic printing method, two developing stations of CA 02227796 l998-0l-23 opposite relative polarity are used to develop a single photoconductor which hasrelatively positive, neutral and negatively charged areas such that two colors can be developed on one photoconductor at the sarne time. Multiple tri-level devices can also be used as with conventional electrophotography producing, for example, six colors 5 from three tri-level units.
In addition to the aforementioned electrophotographic printing methods, another printing method useful in the method of the present invention are so-called direct printing methods lltili~ing solid toners. An example of a direct toner printer is the TonerJet'g~ made by Array Printers in Sweden. In direct printing, the substrate 10 passes through an electrostatic field which attracts toner to the substrate surface. But the toner must first pass through an array of microscopically fine apertures, each surrounded by a ring electrode. Dots are formed directly on the sllbs~ e by charging the ring electrodes to add to the attraction of the substrate and thereby release "jets" of toner towards the substrate. Once in place, these dots of toner are fused in place and 15 the aperture cleaned in pl~al~lion for printing the next line.
Definition of Terms The following terms are used herein:
The term "electrostatically chargeable" as used herein with respect to a material refers to a material having electrical resistivity greater than or equal to 1 ol~ ohm-20 cPntimet.~r The term "Ll~ alen~" as used herein refers to a material wherein the ratio ofthe intensity of undeviated visible light passing through a layer to the incident light is equal to or greater than about 85%.
The term "tr~n~ cçnt" as used herein refers to a material wherein the ratio of 25 the intensity of undeviated visible light passing through a layer to the inc.idt?nt light is less than about 85% but greater than about 20%.
CA 02227796 l998-0l-23 _g_ The term "opaque" as used herein refers to a material wherein the ratio of the intensity of the undeviated visible light passing through a layer to the incident light is 20% or less.
The term "electrostatic printing means" as used herein refers to printing 5 methods in~ln-1ing, but not limited to electrophotography and direct, solid toner printing as described above. However, electrostatic printing means does not refer to electrostatic printing requiring liquid toners used to form images on substrates having conductive and dielectric layers for ret~ining such toners electrostatically.
The term "colorless" as used herein refers to compositions co..l~h~i"g no added 10 dyes or pigm~.nt~ Such compositions may show slight natural color, such as a clear resin with some yellowness. It also refers to cases where the electrostatically chargeable polymeric material ~tt~ched to at least a portion of image-enh~n-ing particles has significantly less chroma (not more than 20%, preferably not more than 10%) co.l,l)al ed to the chroma of any colored toners used in any compositions.
The present invention provides a method of printing image-enh~ncing particles electrostatically. To print image-~.nh~nr.ing particles electrostatically according to the present invention, an image-P.nh~n~.in~ particle which has been modified to behave as a normal toner particle is used. A relatively larger image-~nh~n~ing particle (relative to a 20 normal toner particle) which has been modified to behave as a normal toner particle may be used, as one example. In conventional electrophotography, the trend has been toward smaller toner particle size in order to achieve higher print resolutions. For example, as the spatial resolution of electrophotographic print engines has increased from 1 18 dots per c~.ntimetçr (dpc) to 236 dpc or higher, the particle size of toner has 25 decreased from perhaps 12 microns to 7 microns or lower. As the size ofthe toner has changed, so has the size of the m~gnetic carrier used in two-component developers (from 200 microns for low resolution print engines to 100 microns for high resolution W O 97/08590 PCT~US96/13178 print Pngines, for example). Conversely, if relatively larger image-Pnh~nc ing particles are used (to achieve more of a sparkle rather than luster metallic effect, for P.~r~mplP) the effective toner particle size may be larger than for conventional high resolution electrophotographic toners and will also require larger size magnetic carrier particles in a two-component developer composition. Therefore, as the size of the image-enhancing particles increases the electrophotographic printable resolution will decrease. The same trend towards the use of smaller toner particles and the resultant effect obtained therefrom is evident in other electrostatic processes.
Another advantage to the printing method of the present invention lies in the capability, in one embodiment, of plill~illg the electrostatically printable image-Pnh~n~.ing particles of the present invention in a first print station of a multi-station printer, followed by subsequent compositions printed in registration in subsequent print stations. If larger size electrostatically printable image-Pnh~nrinP particles are printed in the first station at lower resolution, followed by subsequent compositions comprising toner which contains dye and/or pigment which are free of image-enh~nring particles printed at higher resolution in subsequent print stations, the composite image formed will be of higher resolution because the subsequent compositions which do contain dyes and/or pigments will be of higher image contrast than the image-Pnh~ncin~ particle composition which is free of dyes and/or pi~nPntS
Various embodiments of the present invention are possible. The ones discussed below are several possible emborlimPnt~
One embodiment of the method of the present invention is that wherein the first composition is free of ~lP.m~nt (a)(II) and wherein subsequent composition(s) are each free of element (b)a). In such a method the first image is formed from a composition which comprises electrost~tic~lly printable image-enhancing particles but which does not comprise a toner cont~ining dyes and/or pigment~ In the subsequent step(s) each composition from which an image is formed comprises a toner co~ g dyes and/or CA 02227796 l998-0l-23 pi ment.~7 but does not comprise electrostatically printable image-enhancing particles.
Such method may optionally further comprise a step (c) of bonding a clear overl~min~te to the fused image(s) after step (b).
Another embodiment of the method of the present invention is that wherein the 5 first composition is free of element (a)(I) and wherein all subsequent composition(s) except for the last subsequent composition are each free of element (b)(I) and wherein the last subsequent composition comprises (b)(I) but is free of (b)(II). In such a method, the first image is formed from a composition which comprises a toner cont~ining dye(s) and/or pigment(s) but which does not comprise electrostatically 10 printable image-enhancing particles. All of the subsequent images, except for the very last formed image, comprises toner co~ g dye(s) and/or pigment(s) but is free ofelectrostatically printable image-~nh~n~ing particles. The last subsequent image, however, is formed from a composition which does comprise electrostatically image-~nh~n-;ing particles but does not comprise a toner co~ lg dye(s) and/or 15 rigmPnt.~(s). Thus according to this method, layer(s) of color can be provided on top of each layer, followed by a colorfree layer which provides, for example, a sparkle effect due to the presence of the electrostatically printable image-.o.nh~neing particles.
Preferably, according to this method, the substrate is a clear film and the method further comrri~es a step (c) of bonding the fused image(s) to an element selected from 20 the group con~i~fing of a second substrate and an adhesive layer after step (b).
Another embodiment of the method of the present invention is wherein the electrostatically chargeable image-enhancing particles are in at least one composition(s) free of the toner particles, and wherein the electrostatically chargeable image-enhancing particles in the compositions free ofthe toner particles are: (1) of a 25 larger r1imen~ion than the dimensions ofthe toner particles which are in any ofthe compositions which are free of electrostatically chargeable image-enhancing particles;
and (2) of a larger dimension than the dimensions of any toner particles which are CA 02227796 l998-0l-23 combined in any of the compositions with electrostatically printable image-Pnh~nting particles; and (3) of a larger dimension than the dimensions of any electrostatically printable image-~nh~n~ing particles combined in any of the compositions with the toner particles.
A variety of methods of modifying the image-Pnh~n~in~ particles to behave as normal toner particles may be utilized Suitable methods include but are not limited to the following: spray-drying the image-çnh~n~ing particles with toner resin free of dyes and pigments; extruding the image-Pnh~nc.ing particles with toner resin free of dyes and pigments; etc. Extruding image-Pnhz-n~.ing particles with toner resin free of dyes and pigments and then pulverizing the r~enltin~ blend, although useful, can distort and subst~nti~lly reduce the particle size distribution of some image-P.nh~ncin~ particles.
The res~ nt appearance is thus altered substantially as well.
As mentioned previously, the electrostatically chargeable coating must be ~tt~ched to at least a portion of the image-Pnh~n~ing particle. Merely dry blending image-Pnh~n-ing particles with toner powders does not enable the image-P.nh~n~ing particles to be printed electrostatically without significant background dusting. Many ofthese image-Pnh~nring particles that are relatively conductive (such as ~ mimlm flake, for example) are unable to hold a charge so they can be manipulated in the electrostatic process.
Each method of modifying the image-~nh~n-.ing materials to enable them to behave as toner particles has its advantages and disadv~nt~e.e For example, the extrusion process is relatively simple although it may crumple some flake-like image-enhancing particles. ~lnmimlm that is usually used for image-Pnh~nc.ing is pl~r~ ed in a flat, flake form and these flakes are extremely fragile. Mixing flakes with toner resins in high-shear mixers such as Banbury mixers or twin screw extruders can result in crllmplin3~ ofthe flake which decreases the visual effectiveness ofthe image-~nh~n~ing particle.
W O 97/08590 PCT~US96/13178 . -13-Image-Enhancing Particles Useful image-enh~ncing particles which can be used in making the electrostatically printable image-~nh~ncing particles may have a variety of shapes. The image-enhancing particles may be symmetrical or asymmetrical. Examples of specific 5 image-~nh~n~-ing particle shapes include but are not limited to those selected from the group consisting of fiakes, spheres (hollow or solid), and combinations thereof. The image-enhancing particles preferably have ~ m~ters of about 1 to 200 microns, more preferably about 1 to about 100 microns, and most preferably about S to about 50microns. Particles having ~i~meters in the range of about 1-20 microns generally10 exhibit more of a lustrous appearance, while particles having tli~mPters larger than about 20 microns generally have an increasing amount of a sparkle appearance, that increases as the particle size increases Image-Pnh~ncin~ particles that are useful according to the method of the present invention include but are not limited to those selected from the group con~ictin3~; of metallic particles incl--rling but not limited to those selected from the group conci~ting of ~lumin~m, brass, stainless steel, bronze, copper, tin, gold, silver, pl~tin-lm rubidium, and lllix~ s thereof; pearlescent particles in~ ling but notlimited to those selected from the group consisting of metallic oxide-coated mica, metallic oxide-coated glass, metallic oxide-coated polyester, and mi-xtures thereof;
phosphor particles inçl--tling but not limited to metallic doped zinc sulfide, for example copper doped zinc sulfide phosphors; glass particles; metallic coated polyester particles and metallic coated glass particles Examples of metallic coated glass particles include, but are not limited to, the lel.o,~;nective glass beads disclosed in U.S. Patent Nos.
IM~GE-ENHANCING PARTICLES AND SAID PARTICLES
FIELD OF THE rNVENTION
The present invention relates to a novel method of producing graphics employing image-~nh~nl ing particles electrostatically. The invention also relates to novel electrostatically printable image-çnh~nring particles.
BACKGROUND OF THE INVENTION
Decorative graphics for automotive trim and orn~m~nt~tion have been conventionally produced by screen printing an ink onto an adhesive coated film.
Image-enhancing particles are often incorporated into these printing inks to provide an interesting visual appearance such as sparkle, color flop, iri(lesc~n~e or luster.
Representative examples of image-enhancing particles include metallic flake and spherical particles, such as ~ mimlm flake or ~lllmimlm spheres, pearlescent flake pigments such as metallic oxide coated mica, metallic oxide coated glass flake, and metallic oxide coated polyester flake. These image-~nh~n~ing particles are usually in the 1-200 microns tli~m-o.tf!r size range. Particles in the range of about 1-20 microns generally exhibit more of a lustrous appearance, while particles larger than 20 microns generally have an increasing amount of a sparkle appearance, that increases as the particle size increases. Some image-çnh~nçing particles are more functional in nature.
For example, phosphors can be used to make an electrolllminesc~nt lamp or metallic coated glass beads can be used to provide ~ lul~llection.
However, it would be desirable to replace analog printing methods such as screen printing with a digital printing method in order to reduce cycle times and produce short runs economically. In addition, most digital printing processes elimin~te the need for printing plates and significantly reduce job set-up and changeover times.
W O 97/08590 PCT~US96/13178 --2--While digital color printing is well known in the graphics industry, digitally printing the breadth of image-enhancing particles used in the screen printing industry has largely been ignored. This may be due to the particle size and/or the conductivity of many image-enhancing particles such as, for example, ~ mimlm flake. The use of a particular type of image-enhancing particle, ~ ", oxide coated flake-form inorganic crystal, in colored toner formulations is taught in Japanese Patent Kokai No. Sho 62[1987]-100771. Kokai No. Hei 1~1989]-112254 further teaches use of the above mentioned flake-form particles first coated with a black tit~nillm oxide layer in toner formulations that are preferably colored. However, a wider range of decorative or 10 functional effects are desired requiring a much wider range of image-enhancing particles.
Known methods of l~tili7ing image-~.nh~n~ing particles in solid toners involve compounding a separate batch oftoner CO..I~ g image-Pnh~n~ing particles for eachcolor in which an image-Pnh~n-~.in~ effect is desired. For example, green toner may be compounded with metallic flake to produce a metallic green color. Likewise, if ametallic red was desired, metallic flakes would be compounded with red toner, etc.
Thus, for every dirr~;lell~ color and concentration of image-P.nh~n~.ing particles, a separate batch of toner compounded with image-~nh~n~ing particle was required.
Making small batches of toner and image-~nh~n-~in~ particles is a costly process with 20 no economies of scale. Therefore, it would be further desirable to achieve m~ ipl(?
color image-.-.nh~n~.ing effects without having to produce multiple batches of color toner co..l~ il~ image-enh~n~ing particles.
Because print resolution is largely determined by the particle size of toner andmany desirable image-enh~n~ing effects require particle sizes in excess of convention~l higher resolution toner particles sizes, it would be still further desirable to print "
digitally larger image-enh~ncing particles without sacrificing overall image resolution.
SIJMMARY OF THE INVENTION
The present invention, which overcomes the difficulties of known pl in~ g methods, employs an image-~nh~ncing particle at least partially coated with an electrostatically chargeable material free of dyes and pigment~ according to theS restrictions set forth herein. This electrostatically chargeable material may be, for example, a toner material which is free of dyes and pigments. These modified image-~nh~n~ing particles of the invention are referred to herein also as "electrostatically printable image-~nh~nçing particles."
The electrostatically printable image-enh~nring particles of the invention can be 10 used in a number of methods. In one such method, electrophotography, the electrostatically printable image-enh~n-.ing particles can be added to any colored toner (preferably Ll~ls~a~nl or tr~n~ cent colored toner so as not to hide the image-enh~ncing effect) and printed as a dual component mixture or can be applied by itself in a first stage, for example, in a multi-station printer and subsequent colors (in the form 15 of colored toner, for ~x~mple) applied in registration over the image-f.nh~nr.ing particles in the later print stations.
In addition to electrophotographic printing methods, these image-~nh~ncing particles may also be used in other plillLiilg methods employing solid toners such as so-called direct printing. An example of a direct toner printer is the TonerJet~ made by 20 Array Printers in Sweden. In direct printing, the substrate passed through anelectrostatic field which attracts toner to the substrate surface. But the toner must first pass through an array of microscopically fine apertures, each surrounded by a ring electrode. Dots are formed directly on the substrate by charging the ring electrodes to add to the attraction of the substrate and thereby release "jets" of toner towards the 25 substrate. Once in place, these dots of toner are fused in place and the apertures are cleaned in preparation for printing the next line.
For multi-station printers, a plc;rell~;d method of creating an çnh~nced appearance is to apply the amount of image-rnh~nr.ing particles that are desired at the first printing station and to print the desired color in subsequent stations. A common method of creating many colors from only a few primaries is to use cyan, m~grnt~, 5 yellow, and black primaries in what is called a 4-color process. This technique is particularly useful with the current invention and enables one to print many dirre~
colored image-enhancing graphics, without the expense of many diLr~renL developer units or of rl~ning the developer units many times.
We have thus discovered a novel method of printing image-enhancing particles.
10 The method ofthe invention has a number of distinct adv~nt~gç~, in~ iing but not limited to those tii~c~ ed above, when compared to known methods. Our novel method of electrostatically printing image-Pnh~ncin~ particles comprises the steps of:
(a) providing a first image on a substrate via an electrostatic plilllillg meanswherein the first image is formed from a first composition COlll~uliSillg:
(I) optionally, electrostatically plillL~Ic image-enhancing particles, each electrostatically printable image-~nh~nçing particle comprising:
(A) an image-~.nh~n~ing particle; and (B) an electrostatically chargeable material attached to at least a portion of an exterior surface(s) of the image-rnh~nring particle, wl~rein the 20 electrostatically chargeable material is free of dyes and pi m.ont.~ and wherein the electrostatically chargeable material is selected from the group consisting of Ll~n~ cllL materials, tr~n~l~lcP.nt materials, opaque materials, and combinations thereof, wherein the electrostatically chargeable material comprises: (i) an electrostatically chargeable polymeric material, and (ii) optionally a charge controlling 25 compound; wherein no more than 80% of the exterior surface of each image-~nh~nr.in~
particle may have an opaque electrostatically chalgeable material z~tt~hçd thereto;
_S _ (II) optionally toner particles co.-~h~ g a component selected from the group consisting of dyes, pigmP.nt~, and combinations thereof;
wherein at least one of (a)(I) and (a)(II) is present;
(b) optionally providing one or more subsequent image(s) in registration 5 with said first image wherein said subsequent image(s) are independently formed from a subsequent composition, each subsequent composition independently comprising:
(I) optionally, electrostatically printable image-Pnh~nring particles, each electrostatically printable image-Pnh~ncing particle comprising:
(A) an image-P.nh~n~ing particle; and (B) an electrostatically chargeable material attached to at least a portion of an exterior surface(s) of the image-~nh~nr.ing particle, wherein the electrostatically chargeable material is free of dyes and pigments and wherein the electrost~tic~lly chargeable material is selected from the group consisting of transparent materials, tr~n~ cPnt materials, opaque materials, and combinaLions thereof, wherein the electrostatically chargeable material comprises: (i) an electrostatically chargeable polymeric material, and (ii) optionally, a charge controlling compound; wherein no more than 80% of the exterior surface of each image-enhancing particle may have an opaque electrostatically chargeable material attached thereto;
(II) optionally, toner particles col~ g a component selected from the group consisting of dyes, pigmPnt~, and col~ hldLions thereof;
wherein at least one of (b)(I) and (b)(II) is present in each subsequent composition, wherein at least one of said first image and/or said subsequent image(s), if present, are formed from a composition comprising electrostatically printable image-P.nh~n~.ing particles; and (c) fusing the deposited image(s) wherein the deposited image(s) are fused at least after the last deposited image is formed, and optionally, in ~d-lition, after any previous deposited image(s) are formed.
W O 97/08590 PCTrUS96/13178 The present invention also provides the printed substrates prepared according to the method of the invention.
The present invention also provides the above ~ c~ ecl novel electrostatically printable partides, each particle colllpli~ing:
(a) an image-enhancing particle P~ccl~ ing mica particles coated with a layer of black tit~n jllm oxide;
(b) an electrostatically chargeable material ~ ched to at least a portion of an exterior surface(s~ of the image-enh~ncin~ particle, wherein the electrostatically chargeable material is free of dyes and pigm~nt~ and wherein the electrostatically chargeable material is selected from the group con~i~Lillg of transparent materials, tr~n~ c.~nt materials, opaque materials, and coll,bil~aLions thereof, wherein the electrostatically chargeable material comprises: (i) an electrostatically clla~,eable polymeric material, and (ii) optionally, a charge controlling compound; wherein no more than 80% of the exterior surface of each image-enhancing particle may have an opaque electrostatically chargeable material ~ hçd thereto.
One particular printing method useful in the method of the present invention is electrophotography. In eleckophotography~ a latent image is formed on a charged photoconductor by image-wise exposure to a light source such as a laser or a light çmitting diode. The latent image on the photoconductor is then developed with either a single-component or a two-component developer. In either case, the developer is generally metered out onto a rotating sleeve with a perm~n~?ntly aligned m~gnetic core.
In the case of a single-component developer, the developing composition consists of only a m~gnP.tic toner. Because m~gnçtic materials are generally dark in color, single-component developers are mainly used for black and white printing. In order to achieve suitable colors in color printing, two-component developers are used which consist of non-m~gnetic toner(which can therefore be brightly colored) andm~gnetic carrier particles. Typically, tribocharging is used to create opposite electrostatic charges on the toner and magnetic carrier particles which cause the toner to stick to the m~netic carrier. Tribocharging results from the toner and m~gnetic carrier particles rubbing together in the developer unit. The size of the m~gnetic carrier particles relative to the toner particles is generally at least 3 :1.
In either case, single-component or two-component developing, the polarity of the toner particles is opposite to that of the latent image areas on the photoconductor.
In addition, the m~gnit~cle of electrostatic charge holding toner on magnetic carrier particles or the magnetic forces holding a single-component toner on the developer sleeve should not be greater than the electrostatic attractive forces of the latent image areas on the photoconductor. The developer unit is often biased so as to infll-ence the relative polarity and/or m~gnitllde of the latent image areas on the photoconductor.
Once the latent image is developed on the photoconductor, it may be transferred electrostatically to the final substrate, generally by using a corona charging device behind the substrate to attract the toner from the photoconductor to the substrate. In the case of multi-color printing, multiple photoconductors can be used, each developing a color and transferring it to the substrate. Optionally, a single photoconductor can be used with multiple developing stations where after each color is developed it is ~ r~ d first to an intermediate holding member such as an ~cc Im~ tor belt and then to the final substrate after all images have been ~c.cllmlll~ted on the interme~i~te holding member.
After transferring the toner from the photoconductor, residual toner is removed from the photoconductor by means of a brush or flexible scraping blade, residualcharge on the photoconductor is erased and the entire process can be repeated. If the photoconductor is a seamless drum or belt, a longer or continuous image can be formed from multiple revolutions of the photoconductor.
Another type of electrophotography utilizes a so-called tri-level developing scheme. In a tri-level electrophotographic printing method, two developing stations of CA 02227796 l998-0l-23 opposite relative polarity are used to develop a single photoconductor which hasrelatively positive, neutral and negatively charged areas such that two colors can be developed on one photoconductor at the sarne time. Multiple tri-level devices can also be used as with conventional electrophotography producing, for example, six colors 5 from three tri-level units.
In addition to the aforementioned electrophotographic printing methods, another printing method useful in the method of the present invention are so-called direct printing methods lltili~ing solid toners. An example of a direct toner printer is the TonerJet'g~ made by Array Printers in Sweden. In direct printing, the substrate 10 passes through an electrostatic field which attracts toner to the substrate surface. But the toner must first pass through an array of microscopically fine apertures, each surrounded by a ring electrode. Dots are formed directly on the sllbs~ e by charging the ring electrodes to add to the attraction of the substrate and thereby release "jets" of toner towards the substrate. Once in place, these dots of toner are fused in place and 15 the aperture cleaned in pl~al~lion for printing the next line.
Definition of Terms The following terms are used herein:
The term "electrostatically chargeable" as used herein with respect to a material refers to a material having electrical resistivity greater than or equal to 1 ol~ ohm-20 cPntimet.~r The term "Ll~ alen~" as used herein refers to a material wherein the ratio ofthe intensity of undeviated visible light passing through a layer to the incident light is equal to or greater than about 85%.
The term "tr~n~ cçnt" as used herein refers to a material wherein the ratio of 25 the intensity of undeviated visible light passing through a layer to the inc.idt?nt light is less than about 85% but greater than about 20%.
CA 02227796 l998-0l-23 _g_ The term "opaque" as used herein refers to a material wherein the ratio of the intensity of the undeviated visible light passing through a layer to the incident light is 20% or less.
The term "electrostatic printing means" as used herein refers to printing 5 methods in~ln-1ing, but not limited to electrophotography and direct, solid toner printing as described above. However, electrostatic printing means does not refer to electrostatic printing requiring liquid toners used to form images on substrates having conductive and dielectric layers for ret~ining such toners electrostatically.
The term "colorless" as used herein refers to compositions co..l~h~i"g no added 10 dyes or pigm~.nt~ Such compositions may show slight natural color, such as a clear resin with some yellowness. It also refers to cases where the electrostatically chargeable polymeric material ~tt~ched to at least a portion of image-enh~n-ing particles has significantly less chroma (not more than 20%, preferably not more than 10%) co.l,l)al ed to the chroma of any colored toners used in any compositions.
The present invention provides a method of printing image-enh~ncing particles electrostatically. To print image-~.nh~nr.ing particles electrostatically according to the present invention, an image-P.nh~n~.in~ particle which has been modified to behave as a normal toner particle is used. A relatively larger image-~nh~n~ing particle (relative to a 20 normal toner particle) which has been modified to behave as a normal toner particle may be used, as one example. In conventional electrophotography, the trend has been toward smaller toner particle size in order to achieve higher print resolutions. For example, as the spatial resolution of electrophotographic print engines has increased from 1 18 dots per c~.ntimetçr (dpc) to 236 dpc or higher, the particle size of toner has 25 decreased from perhaps 12 microns to 7 microns or lower. As the size ofthe toner has changed, so has the size of the m~gnetic carrier used in two-component developers (from 200 microns for low resolution print engines to 100 microns for high resolution W O 97/08590 PCT~US96/13178 print Pngines, for example). Conversely, if relatively larger image-Pnh~nc ing particles are used (to achieve more of a sparkle rather than luster metallic effect, for P.~r~mplP) the effective toner particle size may be larger than for conventional high resolution electrophotographic toners and will also require larger size magnetic carrier particles in a two-component developer composition. Therefore, as the size of the image-enhancing particles increases the electrophotographic printable resolution will decrease. The same trend towards the use of smaller toner particles and the resultant effect obtained therefrom is evident in other electrostatic processes.
Another advantage to the printing method of the present invention lies in the capability, in one embodiment, of plill~illg the electrostatically printable image-Pnh~n~.ing particles of the present invention in a first print station of a multi-station printer, followed by subsequent compositions printed in registration in subsequent print stations. If larger size electrostatically printable image-Pnh~nrinP particles are printed in the first station at lower resolution, followed by subsequent compositions comprising toner which contains dye and/or pigment which are free of image-enh~nring particles printed at higher resolution in subsequent print stations, the composite image formed will be of higher resolution because the subsequent compositions which do contain dyes and/or pigments will be of higher image contrast than the image-Pnh~ncin~ particle composition which is free of dyes and/or pi~nPntS
Various embodiments of the present invention are possible. The ones discussed below are several possible emborlimPnt~
One embodiment of the method of the present invention is that wherein the first composition is free of ~lP.m~nt (a)(II) and wherein subsequent composition(s) are each free of element (b)a). In such a method the first image is formed from a composition which comprises electrost~tic~lly printable image-enhancing particles but which does not comprise a toner cont~ining dyes and/or pigment~ In the subsequent step(s) each composition from which an image is formed comprises a toner co~ g dyes and/or CA 02227796 l998-0l-23 pi ment.~7 but does not comprise electrostatically printable image-enhancing particles.
Such method may optionally further comprise a step (c) of bonding a clear overl~min~te to the fused image(s) after step (b).
Another embodiment of the method of the present invention is that wherein the 5 first composition is free of element (a)(I) and wherein all subsequent composition(s) except for the last subsequent composition are each free of element (b)(I) and wherein the last subsequent composition comprises (b)(I) but is free of (b)(II). In such a method, the first image is formed from a composition which comprises a toner cont~ining dye(s) and/or pigment(s) but which does not comprise electrostatically 10 printable image-enhancing particles. All of the subsequent images, except for the very last formed image, comprises toner co~ g dye(s) and/or pigment(s) but is free ofelectrostatically printable image-~nh~n~ing particles. The last subsequent image, however, is formed from a composition which does comprise electrostatically image-~nh~n-;ing particles but does not comprise a toner co~ lg dye(s) and/or 15 rigmPnt.~(s). Thus according to this method, layer(s) of color can be provided on top of each layer, followed by a colorfree layer which provides, for example, a sparkle effect due to the presence of the electrostatically printable image-.o.nh~neing particles.
Preferably, according to this method, the substrate is a clear film and the method further comrri~es a step (c) of bonding the fused image(s) to an element selected from 20 the group con~i~fing of a second substrate and an adhesive layer after step (b).
Another embodiment of the method of the present invention is wherein the electrostatically chargeable image-enhancing particles are in at least one composition(s) free of the toner particles, and wherein the electrostatically chargeable image-enhancing particles in the compositions free ofthe toner particles are: (1) of a 25 larger r1imen~ion than the dimensions ofthe toner particles which are in any ofthe compositions which are free of electrostatically chargeable image-enhancing particles;
and (2) of a larger dimension than the dimensions of any toner particles which are CA 02227796 l998-0l-23 combined in any of the compositions with electrostatically printable image-Pnh~nting particles; and (3) of a larger dimension than the dimensions of any electrostatically printable image-~nh~n~ing particles combined in any of the compositions with the toner particles.
A variety of methods of modifying the image-Pnh~n~in~ particles to behave as normal toner particles may be utilized Suitable methods include but are not limited to the following: spray-drying the image-çnh~n~ing particles with toner resin free of dyes and pigments; extruding the image-Pnh~nc.ing particles with toner resin free of dyes and pigments; etc. Extruding image-Pnhz-n~.ing particles with toner resin free of dyes and pigments and then pulverizing the r~enltin~ blend, although useful, can distort and subst~nti~lly reduce the particle size distribution of some image-P.nh~ncin~ particles.
The res~ nt appearance is thus altered substantially as well.
As mentioned previously, the electrostatically chargeable coating must be ~tt~ched to at least a portion of the image-Pnh~n~ing particle. Merely dry blending image-Pnh~n-ing particles with toner powders does not enable the image-P.nh~n~ing particles to be printed electrostatically without significant background dusting. Many ofthese image-Pnh~nring particles that are relatively conductive (such as ~ mimlm flake, for example) are unable to hold a charge so they can be manipulated in the electrostatic process.
Each method of modifying the image-~nh~n-.ing materials to enable them to behave as toner particles has its advantages and disadv~nt~e.e For example, the extrusion process is relatively simple although it may crumple some flake-like image-enhancing particles. ~lnmimlm that is usually used for image-Pnh~nc.ing is pl~r~ ed in a flat, flake form and these flakes are extremely fragile. Mixing flakes with toner resins in high-shear mixers such as Banbury mixers or twin screw extruders can result in crllmplin3~ ofthe flake which decreases the visual effectiveness ofthe image-~nh~n~ing particle.
W O 97/08590 PCT~US96/13178 . -13-Image-Enhancing Particles Useful image-enh~ncing particles which can be used in making the electrostatically printable image-~nh~ncing particles may have a variety of shapes. The image-enhancing particles may be symmetrical or asymmetrical. Examples of specific 5 image-~nh~n~-ing particle shapes include but are not limited to those selected from the group consisting of fiakes, spheres (hollow or solid), and combinations thereof. The image-enhancing particles preferably have ~ m~ters of about 1 to 200 microns, more preferably about 1 to about 100 microns, and most preferably about S to about 50microns. Particles having ~i~meters in the range of about 1-20 microns generally10 exhibit more of a lustrous appearance, while particles having tli~mPters larger than about 20 microns generally have an increasing amount of a sparkle appearance, that increases as the particle size increases Image-Pnh~ncin~ particles that are useful according to the method of the present invention include but are not limited to those selected from the group con~ictin3~; of metallic particles incl--rling but not limited to those selected from the group conci~ting of ~lumin~m, brass, stainless steel, bronze, copper, tin, gold, silver, pl~tin-lm rubidium, and lllix~ s thereof; pearlescent particles in~ ling but notlimited to those selected from the group consisting of metallic oxide-coated mica, metallic oxide-coated glass, metallic oxide-coated polyester, and mi-xtures thereof;
phosphor particles inçl--tling but not limited to metallic doped zinc sulfide, for example copper doped zinc sulfide phosphors; glass particles; metallic coated polyester particles and metallic coated glass particles Examples of metallic coated glass particles include, but are not limited to, the lel.o,~;nective glass beads disclosed in U.S. Patent Nos.
2,963,378 and 3,700,305.
Electrostatically Printable Image-F.nh~n~ing Particles An electrostatically chargeable material is ~tt~he~l to at least a portion of anexterior surface(s) of the image-.onh~ncing particle. The chargeable material which CA 02227796 l99X-01-23 W O 97/08590 PCTnUS96/13178 should be free of dyes and pi~nPnt~ should be transparent or tr~n~ cent The electrostatically chargeable material comprises an electrostastically chargeablepolymeric material and optionally a charge controlling compound (preferably about 1 to about 10% by weight of a charge control compound, if in~lude-l, based on the total weight of the electrostatically chargeable material).
The image-enhancing particle may be partially or completely coated with the chargeable material. Preferably, the image-enhancing particle is completely coated with the electrostatically chargeable material. The coating may be continuous ordiscontinuous. The image-Pnh~n-ing particle should have attached thereto a sufflcient amount of chargeable material such that the image-enh~nc ing material behaves subst~nti llly like a toner particle during the electrostatic printing process (i.e. it should be capable of being moved and positioned via electrostatic printing means). The amount of coating required will vary depending upon the size of the image-Pnh~nring particle and the conductivity of the image-Pnhtln~inp particles. The lower the resistivity ofthe electrostatically chargeable material the thicker and/or more complete the coating should be. The more conductive the image-enh ~n~ing particle the greater the amount and coverage of the electrostatically chargeable coating required. As one example, an image- Pnh mf.ing particle of 10 to 50 microns may have a coating of 0.1 to 2 microns. Preferably the weight ratio of the image-enhancing particle to theelectr ~st Itis~ 111y chargeable material ~tt~l~hPd thereto is about 20:1 to 1:20, more preferably about 5:1 to 1:5, and most preferably about 3:1 to 1:3. One skilled in the art would be able to determine the appropliate amount of electrostatically chal~,eable material that should be attached to the image-P-nh~n~ing particle in order for it to behave as a toner particle.
The composition of the electrostatically chargeable image-Pnh, n~.ing particles should be such that upon electrostatically charging, the particle retains its charge for a sufficient length of time to enable the image-enhancing particle to go through the electrostatic printing process until it is transferred to the substrate and/or subsequently fused. This may also include initial ~tt~çhment to a photoconductor in electrophotography, for example. Typical lengths of time for this process to occur in today's digital color printers can range from less than a second to more than 60seconds. The exact time period necessary for the image-~nh~n~ing particles to retain their charge will depend on the exact method of electrostatic printing employed.Useful electrostatically chal ~,eable polymeric materials include but are not limited to those selected from the group consisting of acrylic and methacrylic polymers and copolymers such as polymethylmeth~rylate and styrene acrylates, polyesters, 10 polyurethanes, polycarbonates, polymers and copolymers of vinyl chloride, copolymers of ethylene with acrylics and m~.th~.rylics including ionically crosslinked types, and mixtures thereof. The electrostatically chargeable material should be ~ s~al ellL or tr~n.qlucent and free of pigm~nt.s and dyes.
Charge controlling compounds are optionally included in the electrostatically 15 chargeable m~tP.ri~l also. The charge controlling compound should be Ll~~ alellL or tr~nqlllç~nt and free of pigments and dyes. The charge controlling compounds arepreferably colorless or nearly colorless. One example of such a charge controlling compound is a quaternary ammonium functional acrylic polymer. The nature of the charge controlling compound can vary depending upon whether positive or negative20 charging toner is desired.
Preferably the electrostatically printable image-enh~nçing particles have average ~ meters of about 1 to about 200 microns, more preferably about l to about 100 microns, and most preferably about 5 to about 50 microns.
Toner The toner useful in the present invention generally comprises a binder resin, pigment, and a charge controlling compound. These toner ingredients are preferably durable upon outdoor exposure when used to make a decorative automotive graphic, W O 97/08590 PCT~US96/13178 -16-for example. A protective coating or overl~min~te (i.e. a film) may also be used to enhance the outdoor durability and/or solvent resistance of the fused toner. Either a protective coating or an ovt;~ te may also be used to provide the desired gloss.
The protective coatings and overl~min~tes are plc:rel~ly clear and colorless. The S o~ te7 for example, may be bonded to an article comprising a substrate having one or more images fused thereon. The overl~min~te may optionally be bonded via an adhesive, for example. The o~ e would be bonded over the images. Examples of suitable protective coatings and overl~min~tec include but are not limited to those selected from the group consisting of acrylic and methacrylic polymers and copolymers 10 such as polymethylmf th~rrylate and styrene acrylates, polyesters, polyureth~nç~, polycarbonates, polymers and copolymers of vinyl chloride, copolymers of ethylene with acrylics and meth~crylics inr.hll1ing ionically cro~link~l types, and mixtures thereof.
Exarnples of suitable binder resins include but are not limited to those selected 15 from the group consisting of acrylic and mP,th~c.rylic polymers and copolymers such as polymethylm~th~rrylate and styrene acrylates, polyesters, polyureth~ne~, polycarbonates, polymers and copolymers of vinyl chloride, copolymers of ethylene with acrylics and methacrylics including ionically crosslinked types, and lnl~Lules thereo~ If the toner is to be made by pulverization methods, then the glass transition 20 temperature (Tg) of the toner binder resin is preferably in the range of about 40-60~C.
The melting or softening point of the toner binder resin is pl c~r~ .bly such that fusing can be easily accomplished.
Examples of suitable pigments include but are not limited to those selected from the group consisting of tit~nillm dioxide, carbon black, phthalocyanines such as 25 Colour Index Pigment 15 or Colour Index Pigment Green 7, quinacridones such as Colour Index Pigment Violet 19 or Colour Index Pigment Red 122.
CA 02227796 l998-0l-23 W O 97/08590 PCT~US96/13178 For use with colored toners, charge controlling compounds are preferably colorless or nearly colorless. One ~i;xa~ lc of such a charge controlling compound is a quaternary ammonium functional acrylic polymer. The nature of the charge controlling compound can vary depending on whether a positive or negative charging toner is 5 desired.
Preferably the toner particles have average ~ mP.t~rs of about 1 to 100 microns, more preferably about 5 to about 50 microns, and most preferably about 5 to about 30 microns.
Additives A flow additive such as a hydrophobic fumed silica may optionally be added as a separate component to the compositions used according to the present inventionfrom which images are formed. Alternatively, and/or additionally such flow additives may be included in the electrostatically chargeable material ~tt~rhed to the image-enhancing particle. Also, alternatively and/or additionally such flow additives may be 15 in~ de~l in the toner co~ g dye(s) and /or pigment(s). It may also be possible to directly attach flow additives to electrostatically printable image-enhancing particles and/or the toner col-l;1ioi~g dye(s)and/or pigment(s) Optionally release agents such as low molecular weight waxes may also be incorporated in a similar fashion.
20 Developer For the electrophotographic process, the developer used may be either a one-component developer where the toner particle has a magnetic core, or a two-component developer where toner particles adhere to larger magnetic carrier particles by virtue of an electrostatic attraction. A two-component developer approach is 25 generally used for color printing due to the color limitations of toner with a magnetic core. In one particular method the electrostatic attraction results from the toner particles and m~gnPtic carrier particles rubbing together and forming an opposite electrostatic charge in a process referred to as "tribocharging". Tribocha,g",g is a particular method of creating an electrostatic charge. The polarity of this charge depends on the respective materials used for the toner and the m~gnP.tic carrier (which 5 may have a polymeric coating) and their position in the triboelectric series. It is therefore possible to have either positive or negative charging toner by suitable selection of the toner material and/or the magnetic carrier material or its optional coating, although toner polarity and m~gnit~1de of its tribocharge value has to be mz~tched to the photoconductor and the polarity/m~gnit-1de of the charge on the 10 photoconductor. The m~gnifude of the tribocharge on the toner should be largeenough to ensure good and complete attraction between the toner and carrier, but not so large as to keep the toner from being attracted to the charged areas of the photoc~ n~ ctor corresponding to the latent image.
Various embodiments of the present invention are possible, including but not 15 limited to the following:
One embodiment involves electrophotographically printing electrostatically printable image-enhancing particles comprising the steps of: forming an image on a photocnnd~1ctor via an electrophotographic means, wherein the image is formed from a ffrst composition comprising a) electrostatically printable image-enhancing particles 20 and (ii) toner particles co..l~i..;.~g dyes and/or pigments. The image is then provided on the substrate by transferring the image from the photoconductor to the substrate via an electrostatic means. Prior to Ll ~,~rel to the substrate the image is optionally first transferred to an ~cc -m~ tor belt via an electrostatic means. The image is then~,~n~f~"ed from the ~c~. lmlll~tor belt to the substrate via either electrostatic or 25 mechanical means.
A second embodiment involves electrophotographically printing electrostatically printable image-Pnh~ncing particles comprising the steps of: Forming a first image on a first photoconductor via an electrophotographic means wherein the first image is formed from the first composition. Next, one or more subsequent image(s) are each formed on separate photoconductors from subsequent compositions via an electrophotographic printing means wherein the subsequent images are eachS independently formed from a subsequent composition. The images are provided on a substrate by transferring the images in registration from the photoconductor to the substrate via an electrostatic means wherein the images are fused at least after the last image is provided on the substrate and optionally, in addition, after any previous image is provided on the substrate.
A third embodiment involves electrophotographically printing electrostatically printable image-~nh~n~ing particles comprising the steps of: follnillg a first image on a photoconductor via an electrophotographic printing means wherein the first image is formed from a first composition. Next, the image is transferred to an ~ccllm~ tQr belt or provided on a substrate via an electrostatic means. Next, one or more subsequent 15 image(s) are each separately formed on the photoconductor via electrophotographic means wherein each subsequent image is each independently formed from a subsequent composition. Each subsequent is image ll~nsrt;lled via electrostatic means to an~ccllmlll~tor belt prior to the formation of a subsequent image on the photoconductor via electrophotographic means. The images are provided on a substrate by transferring 20 the images in registration to a ~ub~LI~e via either electrostatic or m~h~nical means, wherein the images are fused at least after the last image is provided on the substrate and optionally in addition after any previous images are provided on the substrate.
Substrate The substrate on which the image(s) are deposited to prior to fusing of the 25 image can comprise a variety of m~tP.ri~l.c The substrate may be transparent,tr~n~ cent, or opaque. It may or may not be colored. Examples of suitable substrates inc.llld~, but are not limited to, those selected from the group consisting of coated or CA 02227796 l998-0l-23 W O 97/08590 PCT~US96/13178 uncoated paper, and a variety of polymeric films such as polyvinyl chlorides, polyacrylates, ureth~nes, and polyesters and blends or copolymers thereof. Thesesubstrates do not require the presence of any materials nece~ry for the formation of images electrostatically using liquid toners applied by spray, bar coating, or the like.
S EXAMPLES
The invention has been described with reference to various specific and relled embodiments and will be further described by reference to the following detailed ~nlplcs. It is understood, however, that there are many extensions, variations, and modifications on the basic theme of the present invention beyond that 10 shown in the examples and detailed description, which are within the spirit and scope of the present invention. All parts, percentages, ratios, etc., in the Examples and elsewhere throughout are by weight unless indicated otherwise.
Specimens 1-3 Specimens 1-3 describe conventional colored toners and two-component developer systems made therefrom.
Specimen 1-Green Toner and Two-Component Developer Made Therefrom A green toner was prepared by melt mixing 74.0 parts Rohm and Haas Acryloid~ B66 (acrylic copolymer), 20.0 parts of a predispersion of 40% Pigment Green 7 (Sun Chemical Sunfast~) 264-8142) in acrylic copolymer (B66) and 6.0 parts 20 DuPont Triblox~M PC-100 (positive charge control agent) in a twin-screw extruder at 190-210~C. The extrudate was allowed to cool and then jet-milled to an average particle size of 3 .8 microns as measured with a Microtrac FRA particle analyzer. A
two-component developer was prepared by mixing 96 parts polymer coated magnetic carrier (Type 13 from Vertex Image Products, Inc.) with 4 parts toner ofthe present 25 example and 0.04 parts fumed silica (Degussa AEROSIL~ R-504). The resulting tribocharge value was tested to be +20.9 ~Clg, using a blow-offtechnique (VertexImage Products Model T-100 Tribo Tester).
Specimen 2-Cyan Toner and Two-Part Developer Made Therefrom A cyan toner was prepared per the method of Specimen 1 by melt mixing 90.0 parts acrylic copolymer (B66), 6.0 parts of a predispersion of 50% Pigment Blue 15:3 (Ciba-Geigy Irgalite(~) Blue GLG) in acrylic copolymer (B66) and 4.0 parts charge control agent (PC-100). The resulting average particle size was 5.2 microns and the tribocharge value of a two-component developer as prepared per the method of Specimen 1 was +26.9 ~C/g.
Specimen 3-Red Toner and Two-Part Developer Made Therefrom A red toner was prepared per the method of Specimen 1 by melt mixing 83.0 parts acrylic copolymer (B66?, 11.0 parts of a predispersion of 50% Pigment Violet 19 (Miles Quindo(g Red R-6700) in acrylic copolymer (B66) and 6.0 parts charge control agent (PC-100). The resulting average particle size was 6.6 microns and the tribocharge value of a two-component developer as prepared per the method of Specimen 1 was +19.0 ~uC/g.
Example 1 An electrostatically printable image-~nh~ncin3~ particle was plepal~d by melt mixing a mixture of 81 parts Rohm and Haas Acryloid~ B-66 (acrylic copolymer ), 11.7 parts Silberline DF3622 ~ mimlm flake (36 micron average particle diameter), 3.3 parts Silberline LE1735AR ~lllmimlm flake, and 4 parts DuPont TribloxTM PC-100 (positive charge control agent) in a twin -screw extruder at 190-210~ C. The extrudate was allowed to cool and then jet-milled (Nippon IDS-2 jet mill) to an average particle size of 35.4 microns. A two-component developer was prepared by mixing 96 parts Vertex Image Products Type 13 magnetic carrier, 4 parts electrostatically printable image-~nh~ncing particle of the present example and 0.04 part Dugussa AEROSIL~
R-504 fumed silica The re~--lting tribocharge was determined to be +10.7 ,uC/g using a blow-offtechnique (Vertex Image Products Model T-100 Tribo Tester). The two-component developer of the present example was placed in a 3M M- 1800 Mllltifimction Printer (previously available from Minnesota Mining and ~mlf~r,tllring S Colllpall.y) and a test pattern of 5.1 cm solid squares s~pa~led by 0.6 cm borders was printed on paper. The reslllting printed images exhibited metallic sparkle with no background dll.cting Example 2 A green metallic image was created by printing the green toner of Specimen 1 10 in registration over the printed images of Example 1 The re,slllting printed images exhibited a green mP.t~ sparkle with no background d~l~ting Example 3 A blue metallic image was created by printing the cyan toner of Specimen 2 in registration over the m~g~nt~ toner of Specimen 3 which had been printed in 15 registration over the printed images of Example 1. The reslllting printed images exhibited a blue metallic sparkle with no background dusting.
Example 4 An electrostatically chargeable image-rnh~nr.ing particle was prepared per the method of F.~c~mple 1 from a mixture of 61 parts acrylic copolymer (B66), 35 parts copper doped zinc sulfide particles (31 micron average particle size) and 4 parts positive charge control agent (PC-100), except that di~ operating conditions were used during jet-milling reslllting in an average particle size of 21.7 microns. A two-component developer prepared as per the method of Example 1 gave a tribocharge value of +8 . 8 ,uC/g. The resulting printed images formed according to the method of 25 Example 1 were incorporated into an electroluminescent lamp construction and exhibited image-wise electroluminescence.
W O 97/08590 PCT~US96/13178 Example 5 Dry ~ flake was prepared by mixing 300 g. Silberline 3122-AR
~IIlminllm paste (36 microns average per Silberline literature) with 100 g. mineral spirits to form a slurry. The slurry was then filtered in a Buchner funnel with a 5 Whatman #42 filter paper. The filter cake was washed with 300 grams heptane followed by 100 grams ethyl acetate. The press cake was then broken up and allowed to dry in a 77~ C oven for 2 hours.
A clear metallic toner was prepared by melt mixing 63.0 parts Rohm and Haas Acryloid~) B66 (acrylic copolymer), 21.0 parts Union Carbide UCAR~ VAGH (vinyl terpolymer), 12.0 parts dry ~lllmimlm flake as prepared above and 4.0 parts Hoechst VP2036 (negative charge control agent) in a single-screw extruder (15" Buss-Kneader Type PR46) at 216~ C. The extrudate was hammer-milled, and then jet-milled/classified (Donaldson A classifier) to a mean particle size of 29.7 microns as measured with a Microtrac FRA particle analyzer.
A two-component developer was prepared by mixing 95 parts PowderTech Corporation DM070C magnetic carrier (100 micron average size) with 5 parts clearmetallic toner as prepared above. The resulting developer was placed in the first print station of a Xeikon DCP- 1 color printer. Standard Xeikon cyan, magenta and yellow developers (7.5 micron toner mixed with 70 micron magnetic carrier) were placed in 20 subsequent print stations such that the standard Xeikon cyan, magenta and yellow toners were printed over the clear, metallic toner ofthe present example. A 0.076 mm biaxially oriented polyethylene terephth~l~te (PET) film was used as the substrate. The r~lllting printed images exhibited multi-color metallic sparkle corresponding to areas where cyan, m~g~.nt~ and yellow were used to overprint the clear metallic toner.25 However, although useful, the cyan, m~gent~ and yellow toners did not print as uniformly over the clear metallic toner as areas where there was no clear metallic toner.
Example 6 The clear metallic developer of the previous example was placed in the last print station of a Xeikon DCP- 1 color printer and standard Xeikon yellow, cyan and magenta developers were placed in previous print stations such that the clear metallic 5 toner of the previous example was printed over the standard Xeikon yellow, cyan and magenta toners. A clear ov~;-ln..,ii.~te film was used as the printing substrate which consisted of 8 micron aliphatic urethane heat activated adhesive (Zeneca R9630) coated on 0.025 mm aliphatic urethane (Zeneca R9679) coated on a 0.076 mm PET
liner. The r~.s llting printed images were then l~min~ed to 3M Scotchcal~ P-345110 white pressure sensitive adhesive coated film at 138~C (printed surface against Scotchcal~) film) followed by stripping offthe PET liner ofthe o~/t;ll~.,.;l"lle film such that the yellow, cyan and magenta toners were now on top of the clear metallic toner when viewed through the clear overl~min~te film. The resulting l~min~ted images exhibited multi-color metallic sparkle corresponding to areas where yellow, cyan and 15 m~gt~nt~ toners were on top ofthe clear metallic toner. The print quality ofthe yellow, cyan and magenta toners was lm~ffected by the ov~ lLing of the clear metallic toner and thus better than that for the previous example.
The roregoing detailed description and Examples have been given for clarity of understanding only. No lmnece,~s~ly limitations are to be understood therefrom. The 20 invention is not limited to the exact details shown and described, for variations obvious to one skilled in the art will be int~lllded within the invention defined by the claims.
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Electrostatically Printable Image-F.nh~n~ing Particles An electrostatically chargeable material is ~tt~he~l to at least a portion of anexterior surface(s) of the image-.onh~ncing particle. The chargeable material which CA 02227796 l99X-01-23 W O 97/08590 PCTnUS96/13178 should be free of dyes and pi~nPnt~ should be transparent or tr~n~ cent The electrostatically chargeable material comprises an electrostastically chargeablepolymeric material and optionally a charge controlling compound (preferably about 1 to about 10% by weight of a charge control compound, if in~lude-l, based on the total weight of the electrostatically chargeable material).
The image-enhancing particle may be partially or completely coated with the chargeable material. Preferably, the image-enhancing particle is completely coated with the electrostatically chargeable material. The coating may be continuous ordiscontinuous. The image-Pnh~n-ing particle should have attached thereto a sufflcient amount of chargeable material such that the image-enh~nc ing material behaves subst~nti llly like a toner particle during the electrostatic printing process (i.e. it should be capable of being moved and positioned via electrostatic printing means). The amount of coating required will vary depending upon the size of the image-Pnh~nring particle and the conductivity of the image-Pnhtln~inp particles. The lower the resistivity ofthe electrostatically chargeable material the thicker and/or more complete the coating should be. The more conductive the image-enh ~n~ing particle the greater the amount and coverage of the electrostatically chargeable coating required. As one example, an image- Pnh mf.ing particle of 10 to 50 microns may have a coating of 0.1 to 2 microns. Preferably the weight ratio of the image-enhancing particle to theelectr ~st Itis~ 111y chargeable material ~tt~l~hPd thereto is about 20:1 to 1:20, more preferably about 5:1 to 1:5, and most preferably about 3:1 to 1:3. One skilled in the art would be able to determine the appropliate amount of electrostatically chal~,eable material that should be attached to the image-P-nh~n~ing particle in order for it to behave as a toner particle.
The composition of the electrostatically chargeable image-Pnh, n~.ing particles should be such that upon electrostatically charging, the particle retains its charge for a sufficient length of time to enable the image-enhancing particle to go through the electrostatic printing process until it is transferred to the substrate and/or subsequently fused. This may also include initial ~tt~çhment to a photoconductor in electrophotography, for example. Typical lengths of time for this process to occur in today's digital color printers can range from less than a second to more than 60seconds. The exact time period necessary for the image-~nh~n~ing particles to retain their charge will depend on the exact method of electrostatic printing employed.Useful electrostatically chal ~,eable polymeric materials include but are not limited to those selected from the group consisting of acrylic and methacrylic polymers and copolymers such as polymethylmeth~rylate and styrene acrylates, polyesters, 10 polyurethanes, polycarbonates, polymers and copolymers of vinyl chloride, copolymers of ethylene with acrylics and m~.th~.rylics including ionically crosslinked types, and mixtures thereof. The electrostatically chargeable material should be ~ s~al ellL or tr~n.qlucent and free of pigm~nt.s and dyes.
Charge controlling compounds are optionally included in the electrostatically 15 chargeable m~tP.ri~l also. The charge controlling compound should be Ll~~ alellL or tr~nqlllç~nt and free of pigments and dyes. The charge controlling compounds arepreferably colorless or nearly colorless. One example of such a charge controlling compound is a quaternary ammonium functional acrylic polymer. The nature of the charge controlling compound can vary depending upon whether positive or negative20 charging toner is desired.
Preferably the electrostatically printable image-enh~nçing particles have average ~ meters of about 1 to about 200 microns, more preferably about l to about 100 microns, and most preferably about 5 to about 50 microns.
Toner The toner useful in the present invention generally comprises a binder resin, pigment, and a charge controlling compound. These toner ingredients are preferably durable upon outdoor exposure when used to make a decorative automotive graphic, W O 97/08590 PCT~US96/13178 -16-for example. A protective coating or overl~min~te (i.e. a film) may also be used to enhance the outdoor durability and/or solvent resistance of the fused toner. Either a protective coating or an ovt;~ te may also be used to provide the desired gloss.
The protective coatings and overl~min~tes are plc:rel~ly clear and colorless. The S o~ te7 for example, may be bonded to an article comprising a substrate having one or more images fused thereon. The overl~min~te may optionally be bonded via an adhesive, for example. The o~ e would be bonded over the images. Examples of suitable protective coatings and overl~min~tec include but are not limited to those selected from the group consisting of acrylic and methacrylic polymers and copolymers 10 such as polymethylmf th~rrylate and styrene acrylates, polyesters, polyureth~nç~, polycarbonates, polymers and copolymers of vinyl chloride, copolymers of ethylene with acrylics and meth~crylics inr.hll1ing ionically cro~link~l types, and mixtures thereof.
Exarnples of suitable binder resins include but are not limited to those selected 15 from the group consisting of acrylic and mP,th~c.rylic polymers and copolymers such as polymethylm~th~rrylate and styrene acrylates, polyesters, polyureth~ne~, polycarbonates, polymers and copolymers of vinyl chloride, copolymers of ethylene with acrylics and methacrylics including ionically crosslinked types, and lnl~Lules thereo~ If the toner is to be made by pulverization methods, then the glass transition 20 temperature (Tg) of the toner binder resin is preferably in the range of about 40-60~C.
The melting or softening point of the toner binder resin is pl c~r~ .bly such that fusing can be easily accomplished.
Examples of suitable pigments include but are not limited to those selected from the group consisting of tit~nillm dioxide, carbon black, phthalocyanines such as 25 Colour Index Pigment 15 or Colour Index Pigment Green 7, quinacridones such as Colour Index Pigment Violet 19 or Colour Index Pigment Red 122.
CA 02227796 l998-0l-23 W O 97/08590 PCT~US96/13178 For use with colored toners, charge controlling compounds are preferably colorless or nearly colorless. One ~i;xa~ lc of such a charge controlling compound is a quaternary ammonium functional acrylic polymer. The nature of the charge controlling compound can vary depending on whether a positive or negative charging toner is 5 desired.
Preferably the toner particles have average ~ mP.t~rs of about 1 to 100 microns, more preferably about 5 to about 50 microns, and most preferably about 5 to about 30 microns.
Additives A flow additive such as a hydrophobic fumed silica may optionally be added as a separate component to the compositions used according to the present inventionfrom which images are formed. Alternatively, and/or additionally such flow additives may be included in the electrostatically chargeable material ~tt~rhed to the image-enhancing particle. Also, alternatively and/or additionally such flow additives may be 15 in~ de~l in the toner co~ g dye(s) and /or pigment(s). It may also be possible to directly attach flow additives to electrostatically printable image-enhancing particles and/or the toner col-l;1ioi~g dye(s)and/or pigment(s) Optionally release agents such as low molecular weight waxes may also be incorporated in a similar fashion.
20 Developer For the electrophotographic process, the developer used may be either a one-component developer where the toner particle has a magnetic core, or a two-component developer where toner particles adhere to larger magnetic carrier particles by virtue of an electrostatic attraction. A two-component developer approach is 25 generally used for color printing due to the color limitations of toner with a magnetic core. In one particular method the electrostatic attraction results from the toner particles and m~gnPtic carrier particles rubbing together and forming an opposite electrostatic charge in a process referred to as "tribocharging". Tribocha,g",g is a particular method of creating an electrostatic charge. The polarity of this charge depends on the respective materials used for the toner and the m~gnP.tic carrier (which 5 may have a polymeric coating) and their position in the triboelectric series. It is therefore possible to have either positive or negative charging toner by suitable selection of the toner material and/or the magnetic carrier material or its optional coating, although toner polarity and m~gnit~1de of its tribocharge value has to be mz~tched to the photoconductor and the polarity/m~gnit-1de of the charge on the 10 photoconductor. The m~gnifude of the tribocharge on the toner should be largeenough to ensure good and complete attraction between the toner and carrier, but not so large as to keep the toner from being attracted to the charged areas of the photoc~ n~ ctor corresponding to the latent image.
Various embodiments of the present invention are possible, including but not 15 limited to the following:
One embodiment involves electrophotographically printing electrostatically printable image-enhancing particles comprising the steps of: forming an image on a photocnnd~1ctor via an electrophotographic means, wherein the image is formed from a ffrst composition comprising a) electrostatically printable image-enhancing particles 20 and (ii) toner particles co..l~i..;.~g dyes and/or pigments. The image is then provided on the substrate by transferring the image from the photoconductor to the substrate via an electrostatic means. Prior to Ll ~,~rel to the substrate the image is optionally first transferred to an ~cc -m~ tor belt via an electrostatic means. The image is then~,~n~f~"ed from the ~c~. lmlll~tor belt to the substrate via either electrostatic or 25 mechanical means.
A second embodiment involves electrophotographically printing electrostatically printable image-Pnh~ncing particles comprising the steps of: Forming a first image on a first photoconductor via an electrophotographic means wherein the first image is formed from the first composition. Next, one or more subsequent image(s) are each formed on separate photoconductors from subsequent compositions via an electrophotographic printing means wherein the subsequent images are eachS independently formed from a subsequent composition. The images are provided on a substrate by transferring the images in registration from the photoconductor to the substrate via an electrostatic means wherein the images are fused at least after the last image is provided on the substrate and optionally, in addition, after any previous image is provided on the substrate.
A third embodiment involves electrophotographically printing electrostatically printable image-~nh~n~ing particles comprising the steps of: follnillg a first image on a photoconductor via an electrophotographic printing means wherein the first image is formed from a first composition. Next, the image is transferred to an ~ccllm~ tQr belt or provided on a substrate via an electrostatic means. Next, one or more subsequent 15 image(s) are each separately formed on the photoconductor via electrophotographic means wherein each subsequent image is each independently formed from a subsequent composition. Each subsequent is image ll~nsrt;lled via electrostatic means to an~ccllmlll~tor belt prior to the formation of a subsequent image on the photoconductor via electrophotographic means. The images are provided on a substrate by transferring 20 the images in registration to a ~ub~LI~e via either electrostatic or m~h~nical means, wherein the images are fused at least after the last image is provided on the substrate and optionally in addition after any previous images are provided on the substrate.
Substrate The substrate on which the image(s) are deposited to prior to fusing of the 25 image can comprise a variety of m~tP.ri~l.c The substrate may be transparent,tr~n~ cent, or opaque. It may or may not be colored. Examples of suitable substrates inc.llld~, but are not limited to, those selected from the group consisting of coated or CA 02227796 l998-0l-23 W O 97/08590 PCT~US96/13178 uncoated paper, and a variety of polymeric films such as polyvinyl chlorides, polyacrylates, ureth~nes, and polyesters and blends or copolymers thereof. Thesesubstrates do not require the presence of any materials nece~ry for the formation of images electrostatically using liquid toners applied by spray, bar coating, or the like.
S EXAMPLES
The invention has been described with reference to various specific and relled embodiments and will be further described by reference to the following detailed ~nlplcs. It is understood, however, that there are many extensions, variations, and modifications on the basic theme of the present invention beyond that 10 shown in the examples and detailed description, which are within the spirit and scope of the present invention. All parts, percentages, ratios, etc., in the Examples and elsewhere throughout are by weight unless indicated otherwise.
Specimens 1-3 Specimens 1-3 describe conventional colored toners and two-component developer systems made therefrom.
Specimen 1-Green Toner and Two-Component Developer Made Therefrom A green toner was prepared by melt mixing 74.0 parts Rohm and Haas Acryloid~ B66 (acrylic copolymer), 20.0 parts of a predispersion of 40% Pigment Green 7 (Sun Chemical Sunfast~) 264-8142) in acrylic copolymer (B66) and 6.0 parts 20 DuPont Triblox~M PC-100 (positive charge control agent) in a twin-screw extruder at 190-210~C. The extrudate was allowed to cool and then jet-milled to an average particle size of 3 .8 microns as measured with a Microtrac FRA particle analyzer. A
two-component developer was prepared by mixing 96 parts polymer coated magnetic carrier (Type 13 from Vertex Image Products, Inc.) with 4 parts toner ofthe present 25 example and 0.04 parts fumed silica (Degussa AEROSIL~ R-504). The resulting tribocharge value was tested to be +20.9 ~Clg, using a blow-offtechnique (VertexImage Products Model T-100 Tribo Tester).
Specimen 2-Cyan Toner and Two-Part Developer Made Therefrom A cyan toner was prepared per the method of Specimen 1 by melt mixing 90.0 parts acrylic copolymer (B66), 6.0 parts of a predispersion of 50% Pigment Blue 15:3 (Ciba-Geigy Irgalite(~) Blue GLG) in acrylic copolymer (B66) and 4.0 parts charge control agent (PC-100). The resulting average particle size was 5.2 microns and the tribocharge value of a two-component developer as prepared per the method of Specimen 1 was +26.9 ~C/g.
Specimen 3-Red Toner and Two-Part Developer Made Therefrom A red toner was prepared per the method of Specimen 1 by melt mixing 83.0 parts acrylic copolymer (B66?, 11.0 parts of a predispersion of 50% Pigment Violet 19 (Miles Quindo(g Red R-6700) in acrylic copolymer (B66) and 6.0 parts charge control agent (PC-100). The resulting average particle size was 6.6 microns and the tribocharge value of a two-component developer as prepared per the method of Specimen 1 was +19.0 ~uC/g.
Example 1 An electrostatically printable image-~nh~ncin3~ particle was plepal~d by melt mixing a mixture of 81 parts Rohm and Haas Acryloid~ B-66 (acrylic copolymer ), 11.7 parts Silberline DF3622 ~ mimlm flake (36 micron average particle diameter), 3.3 parts Silberline LE1735AR ~lllmimlm flake, and 4 parts DuPont TribloxTM PC-100 (positive charge control agent) in a twin -screw extruder at 190-210~ C. The extrudate was allowed to cool and then jet-milled (Nippon IDS-2 jet mill) to an average particle size of 35.4 microns. A two-component developer was prepared by mixing 96 parts Vertex Image Products Type 13 magnetic carrier, 4 parts electrostatically printable image-~nh~ncing particle of the present example and 0.04 part Dugussa AEROSIL~
R-504 fumed silica The re~--lting tribocharge was determined to be +10.7 ,uC/g using a blow-offtechnique (Vertex Image Products Model T-100 Tribo Tester). The two-component developer of the present example was placed in a 3M M- 1800 Mllltifimction Printer (previously available from Minnesota Mining and ~mlf~r,tllring S Colllpall.y) and a test pattern of 5.1 cm solid squares s~pa~led by 0.6 cm borders was printed on paper. The reslllting printed images exhibited metallic sparkle with no background dll.cting Example 2 A green metallic image was created by printing the green toner of Specimen 1 10 in registration over the printed images of Example 1 The re,slllting printed images exhibited a green mP.t~ sparkle with no background d~l~ting Example 3 A blue metallic image was created by printing the cyan toner of Specimen 2 in registration over the m~g~nt~ toner of Specimen 3 which had been printed in 15 registration over the printed images of Example 1. The reslllting printed images exhibited a blue metallic sparkle with no background dusting.
Example 4 An electrostatically chargeable image-rnh~nr.ing particle was prepared per the method of F.~c~mple 1 from a mixture of 61 parts acrylic copolymer (B66), 35 parts copper doped zinc sulfide particles (31 micron average particle size) and 4 parts positive charge control agent (PC-100), except that di~ operating conditions were used during jet-milling reslllting in an average particle size of 21.7 microns. A two-component developer prepared as per the method of Example 1 gave a tribocharge value of +8 . 8 ,uC/g. The resulting printed images formed according to the method of 25 Example 1 were incorporated into an electroluminescent lamp construction and exhibited image-wise electroluminescence.
W O 97/08590 PCT~US96/13178 Example 5 Dry ~ flake was prepared by mixing 300 g. Silberline 3122-AR
~IIlminllm paste (36 microns average per Silberline literature) with 100 g. mineral spirits to form a slurry. The slurry was then filtered in a Buchner funnel with a 5 Whatman #42 filter paper. The filter cake was washed with 300 grams heptane followed by 100 grams ethyl acetate. The press cake was then broken up and allowed to dry in a 77~ C oven for 2 hours.
A clear metallic toner was prepared by melt mixing 63.0 parts Rohm and Haas Acryloid~) B66 (acrylic copolymer), 21.0 parts Union Carbide UCAR~ VAGH (vinyl terpolymer), 12.0 parts dry ~lllmimlm flake as prepared above and 4.0 parts Hoechst VP2036 (negative charge control agent) in a single-screw extruder (15" Buss-Kneader Type PR46) at 216~ C. The extrudate was hammer-milled, and then jet-milled/classified (Donaldson A classifier) to a mean particle size of 29.7 microns as measured with a Microtrac FRA particle analyzer.
A two-component developer was prepared by mixing 95 parts PowderTech Corporation DM070C magnetic carrier (100 micron average size) with 5 parts clearmetallic toner as prepared above. The resulting developer was placed in the first print station of a Xeikon DCP- 1 color printer. Standard Xeikon cyan, magenta and yellow developers (7.5 micron toner mixed with 70 micron magnetic carrier) were placed in 20 subsequent print stations such that the standard Xeikon cyan, magenta and yellow toners were printed over the clear, metallic toner ofthe present example. A 0.076 mm biaxially oriented polyethylene terephth~l~te (PET) film was used as the substrate. The r~lllting printed images exhibited multi-color metallic sparkle corresponding to areas where cyan, m~g~.nt~ and yellow were used to overprint the clear metallic toner.25 However, although useful, the cyan, m~gent~ and yellow toners did not print as uniformly over the clear metallic toner as areas where there was no clear metallic toner.
Example 6 The clear metallic developer of the previous example was placed in the last print station of a Xeikon DCP- 1 color printer and standard Xeikon yellow, cyan and magenta developers were placed in previous print stations such that the clear metallic 5 toner of the previous example was printed over the standard Xeikon yellow, cyan and magenta toners. A clear ov~;-ln..,ii.~te film was used as the printing substrate which consisted of 8 micron aliphatic urethane heat activated adhesive (Zeneca R9630) coated on 0.025 mm aliphatic urethane (Zeneca R9679) coated on a 0.076 mm PET
liner. The r~.s llting printed images were then l~min~ed to 3M Scotchcal~ P-345110 white pressure sensitive adhesive coated film at 138~C (printed surface against Scotchcal~) film) followed by stripping offthe PET liner ofthe o~/t;ll~.,.;l"lle film such that the yellow, cyan and magenta toners were now on top of the clear metallic toner when viewed through the clear overl~min~te film. The resulting l~min~ted images exhibited multi-color metallic sparkle corresponding to areas where yellow, cyan and 15 m~gt~nt~ toners were on top ofthe clear metallic toner. The print quality ofthe yellow, cyan and magenta toners was lm~ffected by the ov~ lLing of the clear metallic toner and thus better than that for the previous example.
The roregoing detailed description and Examples have been given for clarity of understanding only. No lmnece,~s~ly limitations are to be understood therefrom. The 20 invention is not limited to the exact details shown and described, for variations obvious to one skilled in the art will be int~lllded within the invention defined by the claims.
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Claims (10)
1. A method of electrostatically printing image-enhancing particles comprises the steps of:
(a) providing a first image on a substrate via an electrostatic printing means wherein the first image is formed from a first composition comprising:
(I) optionally, electrostatically printable image-enhancing particles, each electrostatically printable image-enhancing particle comprising:
(A) an image-enhancing particle; and (B) an electrostatically chargeable material attached to at least a portion of an exterior surface(s) of the image-enhancing particle, wherein the electrostatically chargeable material is free of dyes and pigments and wherein the electrostatically chargeable material is selected from the group consisting of transparent materials, translucent materials, opaque materials, and combinationsthereof, wherein the electrostatically chargeable material comprises: (i) an electrostatically chargeable polymeric material, and (ii) optionally a charge controlling compound; wherein no more than 80% of the exterior surface of each image-enhancing particle may have an opaque electrostatically chargeable material attached thereto;
(II) optionally toner particles containing a component selected from the group consisting of dyes, pigments, and combinations thereof;
wherein at least one of (a)(I) and (a)(II) is present;
(b) optionally providing one or more subsequent image(s) in registration with said first image wherein said subsequent image(s) are independently formed from a subsequent composition, each subsequent composition independently comprising:
(I) optionally, electrostatically printable image-enhancing particles, each electrostatically printable image-enhancing particle comprising:
(A) an image-enhancing particle; and (B) an electrostatically chargeable material attached to at least a portion of an exterior surface(s) of the image-enhancing particle, wherein the electrostatically chargeable material is free of dyes and pigments and wherein the electrostatically chargeable material is selected from the group consisting of transparent materials, translucent materials, opaque materials, and combinationsthereof, wherein the electrostatically chargeable material comprises: (i) an electrostatically chargeable polymeric material, and (ii) optionally, a charge controlling compound; wherein no more than 80% of the exterior surface of each image-enhancing particle may have an opaque electrostatically chargeable material attached thereto;
(II) optionally, toner particles containing a component selected from the group consisting of dyes, pigments, and combinations thereof;
wherein at least one of (b)(I) and (b)(II) is present in each subsequent composition, wherein at least one of said first image and/or said subsequent image(s), if present, are formed from a composition comprising electrostatically printable image-enhancing particles; and (c) fusing the deposited image(s) wherein the deposited image(s) are fused at least after the last deposited image is formed, and optionally, in addition, after any previous deposited image(s) are formed.
(a) providing a first image on a substrate via an electrostatic printing means wherein the first image is formed from a first composition comprising:
(I) optionally, electrostatically printable image-enhancing particles, each electrostatically printable image-enhancing particle comprising:
(A) an image-enhancing particle; and (B) an electrostatically chargeable material attached to at least a portion of an exterior surface(s) of the image-enhancing particle, wherein the electrostatically chargeable material is free of dyes and pigments and wherein the electrostatically chargeable material is selected from the group consisting of transparent materials, translucent materials, opaque materials, and combinationsthereof, wherein the electrostatically chargeable material comprises: (i) an electrostatically chargeable polymeric material, and (ii) optionally a charge controlling compound; wherein no more than 80% of the exterior surface of each image-enhancing particle may have an opaque electrostatically chargeable material attached thereto;
(II) optionally toner particles containing a component selected from the group consisting of dyes, pigments, and combinations thereof;
wherein at least one of (a)(I) and (a)(II) is present;
(b) optionally providing one or more subsequent image(s) in registration with said first image wherein said subsequent image(s) are independently formed from a subsequent composition, each subsequent composition independently comprising:
(I) optionally, electrostatically printable image-enhancing particles, each electrostatically printable image-enhancing particle comprising:
(A) an image-enhancing particle; and (B) an electrostatically chargeable material attached to at least a portion of an exterior surface(s) of the image-enhancing particle, wherein the electrostatically chargeable material is free of dyes and pigments and wherein the electrostatically chargeable material is selected from the group consisting of transparent materials, translucent materials, opaque materials, and combinationsthereof, wherein the electrostatically chargeable material comprises: (i) an electrostatically chargeable polymeric material, and (ii) optionally, a charge controlling compound; wherein no more than 80% of the exterior surface of each image-enhancing particle may have an opaque electrostatically chargeable material attached thereto;
(II) optionally, toner particles containing a component selected from the group consisting of dyes, pigments, and combinations thereof;
wherein at least one of (b)(I) and (b)(II) is present in each subsequent composition, wherein at least one of said first image and/or said subsequent image(s), if present, are formed from a composition comprising electrostatically printable image-enhancing particles; and (c) fusing the deposited image(s) wherein the deposited image(s) are fused at least after the last deposited image is formed, and optionally, in addition, after any previous deposited image(s) are formed.
2. The method of claim 1 wherein the image-enhancing particles are each independently selected from the group consisting of metallic particles, pearlescent particles, phosphor particles, metallic coated glass particles, metallic coated polyester particles, glass particles, and combinations thereof.
3. A printed substrate prepared according to the method of claim 1.
4. The method of claim 1 wherein the first composition is free of element (a)(II) and wherein subsequent compositions are each free of element (b)(I).
5. The method of claim 1 wherein the first composition is free of element (a)(I) and wherein all subsequent compositions except for the last subsequent composition are each free of element (b)(I) and wherein the last subsequent composition comprises (b)(I) but is free of (b)(II).
6. The method of claim 1 wherein in providing the first image on the substrate the first image is first formed on a first photoconductor via an electrophotographic means and wherein in providing the one or more subsequent image(s) on the substrate one or more subsequent image(s) are each formed on separate photoconductors from subsequent composition(s) via an electrophotographic means, wherein the first and subsequent image(s) are provided on substrate by transferring the images in registration from the photoconductors to the substrate via an electrostatic means wherein the images are fused at least after the last image is provided on the substrate and optionally, in addition, after any previous image is provided on the substrate.
7. The method of claim 1 wherein the electrostatically chargeable image-enhancing particles are in at least one composition(s) free of the toner particles, and wherein the electrostatically chargeable image-enhancing particles in the compositions free of the toner particles are: (I) of a larger dimension than the dimensions of the toner particles which are in any of the compositions which are free of electrostatically chargeable image-enhancing particles; and (2) of a larger dimension than the dimensions of any toner particles which are combined in any of the compositions with electrostatically printable image-enhancing particles; and (3) of a larger dimension than the dimensions of any electrostatically printable image-enhancing particles combined in any of the compositions with the toner particles.
8. An electrostatically printable image-enhancing particle comprising:
(a) an image-enhancing particle, wherein said image-enhancing particles excludes image-enhancing particles in the form of a flake coated with a layer of black titanium oxide;
(b) an electrostatically chargeable material attached to at least a portion of an exterior surface(s) of the image-enhancing particle, wherein the electrostatically chargeable material is free of dyes and pigments and wherein the electrostatically chargeable material is selected from the group consisting of transparent materials, translucent materials, opaque materials, and combinations thereof, wherein the electrostatically chargeable material comprises: (i) an electrostatically chargeable polymeric material, and (ii) optionally, a charge controlling compound; wherein no more than 80% of the exterior surface of each image-enhancing particle may have an opaque electrostatically chargeable material attached thereto.
(a) an image-enhancing particle, wherein said image-enhancing particles excludes image-enhancing particles in the form of a flake coated with a layer of black titanium oxide;
(b) an electrostatically chargeable material attached to at least a portion of an exterior surface(s) of the image-enhancing particle, wherein the electrostatically chargeable material is free of dyes and pigments and wherein the electrostatically chargeable material is selected from the group consisting of transparent materials, translucent materials, opaque materials, and combinations thereof, wherein the electrostatically chargeable material comprises: (i) an electrostatically chargeable polymeric material, and (ii) optionally, a charge controlling compound; wherein no more than 80% of the exterior surface of each image-enhancing particle may have an opaque electrostatically chargeable material attached thereto.
9. The electrostatically printable image-enhancing particle of claim 8 wherein the image-enhancing; particles are each independently selected from the group consisting of metallic particles, pearlescent particles, phosphor particles, glass particles, metallic coated glass particles, metallic coated polyester particles, and combinations thereof.
10. A printed substrate prepared via an electrostatic method from the electrostatically printable image-enhancing particles of claim 8.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US08/518,822 US5753392A (en) | 1995-08-24 | 1995-08-24 | Method of electrostatically printing image-enhancing particles and said particles |
| US08/518,822 | 1995-08-24 | ||
| PCT/US1996/013178 WO1997008590A1 (en) | 1995-08-24 | 1996-08-14 | Method of electrostatically printing image-enhancing particles and said particles |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2227796A1 true CA2227796A1 (en) | 1997-03-06 |
Family
ID=24065654
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002227796A Abandoned CA2227796A1 (en) | 1995-08-24 | 1996-08-14 | Method of electrostatically printing image-enhancing particles and said particles |
Country Status (9)
| Country | Link |
|---|---|
| US (2) | US5753392A (en) |
| EP (1) | EP0846283B1 (en) |
| JP (1) | JPH11512193A (en) |
| KR (1) | KR19990037707A (en) |
| CN (1) | CN1127678C (en) |
| CA (1) | CA2227796A1 (en) |
| DE (1) | DE69606544T2 (en) |
| ES (1) | ES2142083T3 (en) |
| WO (1) | WO1997008590A1 (en) |
Families Citing this family (32)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6979523B1 (en) * | 1995-04-07 | 2005-12-27 | Hewlett-Packard Development Company, Lp | Toner material and method utilizing same |
| US6242056B1 (en) | 1998-05-08 | 2001-06-05 | Innovative Concepts Unlimited, Llc | Process for applying light-emission-enhancement microbead paint compositions |
| JP3473513B2 (en) * | 1999-07-27 | 2003-12-08 | 東洋製罐株式会社 | Printing method on can body |
| DE10124657A1 (en) * | 2001-05-18 | 2002-11-21 | Merck Patent Gmbh | Electrophotographic dry toner with angle-dependent gloss pigments |
| DE60202617T2 (en) * | 2001-08-02 | 2006-03-23 | 3M Innovative Properties Co., St. Paul | OPTICALLY CLEAR AND ANTISTATIC ADHESIVE ADHESIVE |
| US9458324B2 (en) | 2002-09-13 | 2016-10-04 | Viava Solutions Inc. | Flakes with undulate borders and method of forming thereof |
| US20070096646A1 (en) * | 2005-10-28 | 2007-05-03 | Van Nice Harold L | Electroluminescent displays |
| WO2008069953A1 (en) * | 2006-12-01 | 2008-06-12 | World Properties, Inc. | El panel with thermally transferred rear electrode |
| CN101657522B (en) * | 2007-04-13 | 2014-05-07 | 3M创新有限公司 | Antistatic optically clear pressure sensitive adhesive |
| US8039183B2 (en) * | 2007-10-25 | 2011-10-18 | Xerox Corporation | Resin-coated pearlescent or metallic pigment for special effect images |
| JP2009193069A (en) | 2008-02-13 | 2009-08-27 | Jds Uniphase Corp | Medium for laser printing including optical special effect flake |
| US7998649B2 (en) * | 2008-03-03 | 2011-08-16 | Xerox Corporation | Grafting functionalized pearlescent or metallic pigment onto polyester polymers for special effect images |
| US8394562B2 (en) * | 2009-06-29 | 2013-03-12 | Xerox Corporation | Toner compositions |
| US20110318682A1 (en) * | 2010-06-28 | 2011-12-29 | Fuji Xerox Co., Ltd. | Toner, developer, toner cartridge, and image forming apparatus |
| US8859176B2 (en) | 2010-06-28 | 2014-10-14 | Fuji Xerox Co., Ltd. | Toner, developer, toner cartridge, and image forming apparatus |
| US8722290B2 (en) | 2010-06-28 | 2014-05-13 | Fuji Xerox Co., Ltd. | Toner, developer, toner cartridge, and image forming apparatus |
| JP5867023B2 (en) | 2011-11-28 | 2016-02-24 | 富士ゼロックス株式会社 | Toner, developer, toner cartridge, process cartridge, image forming apparatus, and image forming method |
| JP5915128B2 (en) * | 2011-12-05 | 2016-05-11 | 富士ゼロックス株式会社 | Electrostatic image developing toner, electrostatic image developer, toner cartridge, process cartridge, and image forming apparatus |
| JP6044086B2 (en) | 2012-03-13 | 2016-12-14 | 富士ゼロックス株式会社 | Electrostatic latent image developing toner, developer, toner cartridge, process cartridge, and image forming apparatus |
| JP5857834B2 (en) | 2012-03-26 | 2016-02-10 | 富士ゼロックス株式会社 | Developer, process cartridge, and image forming apparatus |
| US20150111142A1 (en) * | 2012-05-02 | 2015-04-23 | Eastman Kodak Company | Non-porous dry toner particles for metallic printed effect |
| US9052624B2 (en) | 2012-05-02 | 2015-06-09 | Eastman Kodak Company | Use of fluorescing toners for imaging |
| US9323169B2 (en) | 2012-05-02 | 2016-04-26 | Eastman Kodak Company | Preparing color toner images with metallic effect |
| US8936897B2 (en) | 2012-05-02 | 2015-01-20 | Eastman Kodak Company | Enhancing color toner images with fluorescing magenta toners |
| US9261808B2 (en) | 2012-05-02 | 2016-02-16 | Eastman Kodak Company | Highlighting color toner images with fluorescing toners |
| AU2014200724B2 (en) * | 2012-07-24 | 2015-09-17 | Fujifilm Business Innovation Corp. | Image forming apparatus, and image forming method |
| JP5954018B2 (en) * | 2012-07-24 | 2016-07-20 | 富士ゼロックス株式会社 | Image forming apparatus |
| US8936893B2 (en) | 2013-03-15 | 2015-01-20 | Eastman Kodak Company | Fluorescing yellow toner particles and methods of use |
| US9618868B2 (en) | 2013-04-30 | 2017-04-11 | Eastman Kodak Company | Metallic toner particles for providing metallic effect |
| US9259953B2 (en) | 2013-09-27 | 2016-02-16 | Eastman Kodak Company | Tactile images having coefficient of friction differences |
| JP6459257B2 (en) * | 2014-07-08 | 2019-01-30 | 富士ゼロックス株式会社 | Image forming apparatus |
| EP3374445B1 (en) * | 2016-03-04 | 2019-09-25 | Hp Indigo B.V. | Electrophotographic composition |
Family Cites Families (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2963378A (en) * | 1955-04-25 | 1960-12-06 | Minnesota Mining & Mfg | Ass beads hemispherically reflectorled with metallic coating and compositions thereof |
| US3700305A (en) * | 1970-12-14 | 1972-10-24 | Minnesota Mining & Mfg | Retroreflective microspheres having a dielectric mirror on a portion of their surface and retroreflective constructions containing such microspheres |
| US4731239A (en) * | 1983-01-10 | 1988-03-15 | Gordon Robert T | Method for enhancing NMR imaging; and diagnostic use |
| JPH0723974B2 (en) * | 1985-10-29 | 1995-03-15 | 三田工業株式会社 | Electrophotographic metal contactor |
| JPH01112254A (en) * | 1987-10-23 | 1989-04-28 | Mita Ind Co Ltd | Metallic toner composition |
| JPH0692357B2 (en) * | 1989-10-18 | 1994-11-16 | キヤノン株式会社 | Toner for developing electrostatic image containing guanidine compound and guanidine compound |
| US5177877A (en) * | 1989-12-28 | 1993-01-12 | Am International, Inc. | Dryer-fuser apparatus and method for high speed electrophotographic printing device |
| JP2623919B2 (en) * | 1990-06-06 | 1997-06-25 | 富士ゼロックス株式会社 | Electrophotographic toner composition |
| EP0467439B1 (en) * | 1990-07-19 | 1996-06-12 | Agfa-Gevaert N.V. | Dry electrostatographic developer composition |
| JP2623938B2 (en) * | 1990-08-21 | 1997-06-25 | 富士ゼロックス株式会社 | Electrophotographic toner |
| US5147745A (en) * | 1990-10-29 | 1992-09-15 | Eastman Kodak Company | Apparatus for producing raised multiple color images |
| JP2609356B2 (en) * | 1990-11-28 | 1997-05-14 | 三田工業株式会社 | Negatively chargeable electrophotographic toner |
| US5326662A (en) * | 1992-07-01 | 1994-07-05 | Xerox Corporation | Passivated toner compositions and processes thereof |
| JP3373610B2 (en) * | 1993-08-23 | 2003-02-04 | オリヱント化学工業株式会社 | Chargeable resin powder and related technologies |
-
1995
- 1995-08-24 US US08/518,822 patent/US5753392A/en not_active Expired - Fee Related
-
1996
- 1996-08-14 DE DE69606544T patent/DE69606544T2/en not_active Expired - Fee Related
- 1996-08-14 JP JP9510328A patent/JPH11512193A/en not_active Ceased
- 1996-08-14 CN CN96196473A patent/CN1127678C/en not_active Expired - Fee Related
- 1996-08-14 CA CA002227796A patent/CA2227796A1/en not_active Abandoned
- 1996-08-14 ES ES96928171T patent/ES2142083T3/en not_active Expired - Lifetime
- 1996-08-14 WO PCT/US1996/013178 patent/WO1997008590A1/en active IP Right Grant
- 1996-08-14 KR KR1019980701186A patent/KR19990037707A/en active IP Right Grant
- 1996-08-14 EP EP96928171A patent/EP0846283B1/en not_active Expired - Lifetime
-
1998
- 1998-05-11 US US09/075,886 patent/US5910388A/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| DE69606544T2 (en) | 2000-09-21 |
| ES2142083T3 (en) | 2000-04-01 |
| JPH11512193A (en) | 1999-10-19 |
| EP0846283A1 (en) | 1998-06-10 |
| KR19990037707A (en) | 1999-05-25 |
| EP0846283B1 (en) | 2000-02-02 |
| US5753392A (en) | 1998-05-19 |
| WO1997008590A1 (en) | 1997-03-06 |
| CN1127678C (en) | 2003-11-12 |
| CN1194040A (en) | 1998-09-23 |
| US5910388A (en) | 1999-06-08 |
| DE69606544D1 (en) | 2000-03-09 |
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