CN101302368A - Aqueous ink, ink set, image forming method and image forming apparatus - Google Patents

Abstract

An aqueous ink used together with a black ink containing a self-dispersion pigment, wherein the aqueous ink contains a reactive component for destabilizing the dispersion state of the self-dispersion pigment, the dynamic surface tension of the aqueous ink at a lifetime of 30 milliseconds is 41 mN/m or more, and the dynamic surface tension of the aqueous ink at a lifetime of 500 milliseconds is from 28 mN/m or more to 38 mN/m or less as determined by a maximum bubble pressure method.

Description

Aqueous ink, complete China ink, image forming method and image forming apparatus

Technical field

The present invention relates to be particularly suitable for being used in the aqueous ink in the ink-jet recording method, and the complete China ink, image forming method and the image forming apparatus that use this aqueous ink.

Background technology

Because can carry out record, and can obtain the feature of high-definition picture at a high speed, so ink-jet recording method is widely used in every field by the record-header that use has many mouthfuls of high-density with lower noise.

Can access pigment acts on ink-jet recording method as China ink (pigment inks) usefulness of coloured material the China ink that comprises of the good record goods of image color height and fastness so far.For pigment inks, proposed to comprise the black ink of carbon black and dispersion agent and comprised not use dispersion agent and the black ink (referring to Japanese Patent Application Laid-Open S63-152681, S64-006074 and H08-003498) of the self-dispersion type pigment of dispersed color.

In recent years, in office, school and shop, panchromatic record goods are used as various propagandas (report) material and notice material usually.Therefore, require ink-jet recording method not only to form the high quality black image, and form high-quality full-colour image.In the formation of this full-colour image, use various so-called common paper, as copy paper, propaganda paper (paper for reporting), scratch paper, letter paper, bond paper and continuous business form (continuous business form).In recent years, based on the viewpoint of environment protection and conservation of resources, the common paper that will comprise salvage material is widely used as recording medium.Thus, though when with various common paper when the recording medium, study as the composition and the physical properties of the China ink that is used to form high quality graphic based on various viewpoints.

In ink-jet recording method,, extensively be used in combination above-mentioned this type of pigment inks and other China inks, especially color ink to form full-colour image as black ink.The specific examples of this type of color ink comprises and is selected from least a of magenta ink, cyan ink, yellow ink, red ink, green ink and blue ink.At this moment, for common complete China ink, following character to various China inks is regulated.More specifically, for color ink, in order to improve black set ability and to prevent that the purpose of bleeding from appearring in the boundary between the image that forms with multiple color ink, the perviousness that color ink is entered in the recording medium is high relatively.For black ink, in order to improve character (character) quality, with black ink enter perviousness in the recording medium be provided with compare with color ink relative low.In other words, make the surface tension of black ink and the surface tension of various color ink be respectively relative high and relative low.When the complete China ink with this black ink and color ink is used to form image, may cause following point in some cases.That is, can cause in some cases that bleeding occurs in the image that forms with black ink and the image that forms with color ink between the phenomenon (bleeding) of boundary member or black ink mix with color ink unevenly and reduce the phenomenon of picture quality.In order to suppress the generation of this bleeding, proposed wherein to use first China ink and with second China ink of the first China ink reaction, and use second China ink with the recording method (referring to Japanese Patent Application Laid-Open H11-343441) of the region overlapping of using first China ink.

The black ink of using color ink in order to suppress the purpose that bleeding takes place and comprising pigment with situation about overlapping each other under, in some cases, the color ununiformity that the image color of gained image wherein or tone change according to the order of administration of color ink and black ink may take place.In order to suppress the appearance of this color ununiformity, proposed that black ink comprises pigment and salt, color ink comprises and is used for stable pigments at the complete China ink of this kind of the component of the dispersion state of black ink, and image forming method (referring to Japanese Patent Application Laid-Open 2001-150793 and 2001-152059).

In recent years, in order in ink-jet recording method, to reach very excellent images quality, carried out record-header in main scanning direction 2 times or bilateral scanning repeatedly, thereby record has the image (hereinafter being called " multipass record (multi-pass recording ") of the width identical with record-header length.When carrying out multipass when record, though when spray a kind of China ink the quantity of nozzle when increasing, or when the width increase of a plurality of jet orifices configurations of wherein spraying a kind of China ink, can not fully shorten writing time in some cases.Thus, in order to shorten writing time, attempt in the working direction of record-header main-scanning and direction of retreat both direction, to write down (hereinafter being called " bidirectional record "), or the image (hereinafter being called " single pass record ") of the main-scanning record unit area by record-header.Carry out record by combination single pass record and bidirectional record, promptly carry out the single pass bidirectional record, thereby need not on recording medium, repeatedly to scan a unit area, therefore can shorten writing time greatly.

Yet the result as inventor's research has found to cause problem as described below when carrying out high-speed record such as single pass bidirectional record.Found significantly to cause the problem of bleeding.In addition, find, as be described in invention among Japanese Patent Application Laid-Open 2001-150793 and the 2001-152059, when use black ink for the generation that suppresses bleeding and with the color ink of black ink reaction so that it when overlapping each other, significantly causes the problem of color ununiformity.In the image-region that writes down in the mode with the overlapping black ink of reactive color ink and overlapping mode with reactive color ink writes down with black ink image-region and the image deposited, this color ununiformity is especially remarkable.In brief, when various common paper were used as recording medium, the invention that is described among Japanese Patent Application Laid-Open 2001-150793 and the 2001-152059 was not enough to as the method that forms the high-caliber high quality graphic that requires in recent years.

Summary of the invention

Therefore, the purpose of this invention is to provide a kind of aqueous ink, even when writing down as the single pass bidirectional record under high speed, this aqueous ink also can provide and suppress the image that bleeding or color ununiformity take place, and can reach high image quality.Another object of the present invention provides complete China ink, image forming method and the image forming apparatus that uses this aqueous ink.

Above-mentioned purpose can realize through the following description of the present invention.More specifically, aqueous ink according to the present invention is the aqueous ink of using with the black ink that contains self-dispersion type pigment, wherein this aqueous ink comprises the reactive component that is used to stablize self-dispersion type colo(u)rant dispersion state, the dynamic surface tension of this aqueous ink 30 milliseconds of life-spans of being measured by maximum bubble pressure method is more than the 41mN/m, this aqueous ink the dynamic surface tension in 500 milliseconds of life-spans be more than the 28mN/m to 38mN/m.

Complete China ink according to yet another embodiment of the invention is the complete China ink that comprises multiple China ink, and wherein this complete China ink comprises above-mentioned aqueous ink and above-mentioned black ink.

According to the image forming method of further embodiment of the present invention for using the black ink that contains self-dispersion type pigment and at least a aqueous ink to form the image forming method of image, wherein this aqueous ink is above-mentioned aqueous ink, this black ink is above-mentioned black ink, and the mode that the image that forms with the image that forms with black ink and use China ink overlaps each other in subregion at least forms image.

The image forming apparatus of an embodiment is to be used for containing the black ink of self-dispersion type pigment and the image forming apparatus that at least a aqueous ink forms image by use again according to the present invention, wherein this aqueous ink is above-mentioned aqueous ink, this black ink is above-mentioned black ink, and this equipment comprises and is used for the unit that mode that the image that forms with the image that forms with black ink and use China ink overlaps each other in subregion at least forms image.

According to the present invention, a kind of aqueous ink can be provided, even when carrying out high-speed record such as single pass bidirectional record, this aqueous ink also can provide the image that suppresses bleeding or the generation of color ununiformity, and can reach high image quality.According to another embodiment of the present invention, can provide the complete China ink, image forming method and the image forming apparatus that use this aqueous ink.

With reference to accompanying drawing, from the description of following exemplary, further feature of the present invention will become apparent.

Description of drawings

The schematically illustrated exemplary ink jet recording device of Fig. 1.

The schematically illustrated exemplary record of a Fig. 2 box.

Embodiment

Below will describe the present invention in detail by embodiment preferred.

Aqueous ink according to the present invention is the aqueous ink of using with the black ink that contains self-dispersion type pigment, this aqueous ink comprises the reactive component that is used to stablize self-dispersion type colo(u)rant dispersion state, the dynamic surface tension of this aqueous ink 30 milliseconds of life-spans of being measured by maximum bubble pressure method is more than the 41mN/m, this aqueous ink the dynamic surface tension in 500 milliseconds of life-spans be more than the 28mN/m to 38mN/m.

In addition, the maximum bubble pressure method that is used to measure dynamic surface tension among the present invention is following method.Particularly, maximum bubble pressure method is a kind of like this method: measure release and be formed at the needed peak pressure of bubble that immerses probe (kapillary) top in the testing liquid, draw surface tension from this peak pressure.Life-span (surperficial timeliness) is meant in maximum bubble pressure method, discharges time between moment that the back forms new bubble surface to the moment (equaling the moment of the radius of probe tip when the radius-of-curvature of bubble) that the bulla when probe tip forms bubble is pressed from a bubble in probe tip.Dynamic surface tension among the present invention is the value 25 ℃ of measurements.

In the present invention, the black ink that will contain self-dispersion type pigment is called " pigment black ink ".The aqueous ink that comprises the reactive component that is used for stable pigments black ink self-dispersion type colo(u)rant dispersion state is called " reactive China ink ".The China ink that does not comprise the reactive component that is used for stable pigments China ink self-dispersion type colo(u)rant dispersion state is called " non-reacted China ink ".In addition, reactive China ink and non-reacted China ink can be color ink or black ink.Yet, especially preferred in the present invention color ink.

In the present invention, the method that is used for various China inks are administered to recording medium mainly comprises following two steps.At first reactive China ink is applied to and uses the subregion at least of pigment black ink, then the pigment black ink is applied to the subregion at least of using reactive China ink.Perhaps, at first use the pigment black ink, then reactive China ink is applied to the subregion at least of using the pigment black ink.Above-mentioned two kinds of methods can make up mutually.In this case, in addition restriction especially of the order of administration that various China inks are applied to recording medium.

At this moment, the amount of application of the amount of application preferred reactive China ink of various China inks is 2/100 to 50/100, with respect to the amount of application of pigment black ink.In other words, the amount of application of reactive China ink preferred more than 2 to below 50, when the amount of pigment inks is 100.The reason that the amount of application of various China inks preferably falls into above-mentioned each scope is as follows.If with respect to the amount of application of pigment black ink, the amount of application of reactive China ink is too little, may not fully reach effect of the present invention in some cases.On the other hand, if with respect to the amount of application of pigment black ink, the amount of application of reactive China ink is too big, may occur in some cases new fuzzy, thereby reduce picture quality.

In the present invention, even when under high speed, writing down, can suppress the generation of bleeding or color ununiformity as the single pass bidirectional record.In other words, can reduce the different color ununiformity that cause of order of administration, take place to suppress bleeding by reactive China ink and pigment black ink.The reason that reaches this effect it be unclear that.Yet the result as inventor's research thinks that its reason is attributable to following mechanism.

[having the mechanism that forms image at the dynamic surface tension in 30 milliseconds of life-spans during as the reactive China ink more than the 41mN/m] when using

The importance of the reactive China ink of definition at the dynamic surface tension in 30 milliseconds of life-spans below will at first be described.The inventor studies the reactive black character that can solve problem of the present invention, and this reactivity China ink uses various pigment black ink and reactive black as the China ink that can be used in ink-jet recording method.Particularly, the inventor studies in the viewpoint of the dynamic surface tension character in 10 milliseconds and 1000 milliseconds life-spans based on the China ink that control has received publicity so far.Yet, even found that when using any condition of the dynamic surface tension that has received publicity so far, the viewpoint based on solving problem of the present invention still can not obtain effect.

Thus, the inventor studies in the following manner: suppose ideal model as the black adoptable condition on the recording medium, estimate each ink droplet jet volume and rise the behavior of this following small ink droplet for for example 6 skins.As a result, find the following fact.More specifically, found that the time difference when pigment black ink and reactive China ink contact with each other is extremely short on recording medium, be about 20 milliseconds to 50 milliseconds, do not considered nozzle arrangements and parameter such as injection frequency in the record-header.Thus, the inventor has paid close attention to this time difference and has studied.As a result, found that color ununiformity and the reactive China ink in the record goods shows the strongest dependency between the dynamic surface tension in 30 milliseconds of life-spans, that is, this dynamic surface tension is an essential factor.The inventor thinks that reactive China ink hints the following fact in the dynamic surface tension value in 30 milliseconds of life-spans and the strong correlation between the color ununiformity.Think: comprise the behavior of the reactive China ink of the perviousness that enters in the recording medium etc., the time point after reactive China ink being applied to 30 milliseconds of recording mediums is controlled the reactive balance between reactive China ink and the pigment black ink.Think that this reactive balance has determined the color ununiformity that connects the image of using these China ink formation by a kind of a kind ofly.

Below form image with considering to be used in combination with the pigment black ink as having defined in the present invention at the reactive China ink of the dynamic surface tension character in 30 milliseconds of life-spans or the reactive China ink that do not have this character.In addition, in following consideration, think that the perviousness that the pigment black ink is entered in the recording medium in order to improve the character quality is relatively little.In other words, think that (static state) surface tension that makes pigment black ink and color ink is relative respectively big and little.

(1) use the dynamic surface tension that has 30 milliseconds of life-spans as 41mN/m more than and contain the situation of the reactive China ink of reactive component and pigment black ink:

(1-1) use the situation of various China inks to overlap each other with the order of pigment black ink and reactive China ink:

When at first the pigment black ink being administered to recording medium, the pigment black ink covers recording medium.At this moment, it is slow relatively that the pigment black ink is infiltrated recording medium, so the self-dispersion type pigment in the pigment black ink begins to assemble on the recording medium surface.At this moment, use reactive China ink with overlapping pigment black ink.At this moment, the pigment black ink with character of slow infiltration recording medium contacts in the recording medium surface under liquid state with reactive China ink.Therefore, pigment black ink and reactive China ink its at the interface each other short mix to produce the state of the homogeneous that becomes easily.Make pigment assemble by the effect of the reactive component in the reactive China ink and carry out fast and equably, so that pigment is present near the recording medium surface with the distribution of homogeneous.As a result, can improve image and image color homogeneity.

(1-2) use the situation of various China inks to overlap each other with the order of reactive China ink and pigment black ink:

When at first reactive China ink being administered to recording medium, reactive China ink covers recording medium.Use the pigment black ink then with overlapping reactive China ink.At this moment, have dynamic surface tension 30 milliseconds of life-spans be more than the 41mN/m reactive China ink since its high surface tension do not infiltrate at once in the recording medium and and be present in the recording medium surface with liquid state.In this way, reactive China ink contacts in the recording medium surface under liquid state with the pigment black ink.Therefore, pigment black ink and reactive China ink its at the interface each other short mix to produce the state of the homogeneous that becomes easily.Make pigment assemble by the effect of the reactive component in the reactive China ink and carry out fast and equably, so that pigment is present near the recording medium surface with the distribution of homogeneous.As a result, can improve image and image color homogeneity.

When under high speed, writing down, repeat (1-1) and record (1-2) as the single pass bidirectional record.In this way, formation is wherein used various China inks with the pigment black ink and the order of reactive China ink and is used various China inks with zone that overlaps each other and the image of depositing with the order regional and and pigment black ink black with reactivity that overlaps each other.Yet, make the homogeneity of image and image color become good by use China ink according to the present invention at (1-1) with (1-2) under two kinds of situations, the color ununiformity that is caused by bidirectional record does not consequently take place.

(2) use the dynamic surface tension have 30 milliseconds of life-spans less than 41mN/m and contain reactive component and the situation of the reactive China ink of pigment black ink:

(2-1) use the situation of various China inks to overlap each other with the order of pigment black ink and reactive China ink:

Image homogeneity and image color can be by being improved with (1-1) middle same mechanism of describing.

(2-2) use the situation of various China inks to overlap each other with the order of reactive China ink and pigment black ink:

When at first reactive China ink being administered to recording medium, reactive China ink covers recording medium.Use the pigment black ink then with overlapping reactive China ink.At this moment, before the pigment black ink is applied to recording medium, have at the dynamic surface tension in 30 milliseconds of life-spans black owing to its low surface tension begins to penetrate in the recording medium less than the reactivity of 41mN/m.Therefore, the reactive China ink that contacts with each other on the recording medium surface under liquid state and the ratio of pigment black ink become relatively low, thereby produce the mixed uniformly state that is easy to.Also make and carry out unevenly, so that pigment is present near the recording medium surface unevenly by the pigment gathering of the effect of reactive component in the reactive China ink.At this moment, the part of gathering pigment very thin (thinly) existence causes the blank sensation of turning white.As a result, it is inhomogeneous that image becomes, and image color can not fully obtain in some cases.

When under high speed, writing down, repeat (1-1) and record (1-2) as the single pass bidirectional record.In this way, formation is used various China inks with the pigment black ink and the order of reactive China ink and is used various China inks with zone that overlaps each other and the image of depositing with the order regional and and pigment black ink black with reactivity that overlaps each other.Therefore, in writing down, alternately form even image and inhomogeneous image every, thereby the color ununiformity occurs.

[at the dynamic surface tension in 500 milliseconds of life-spans]

As mentioned above, necessary in the present invention is: reactive China ink comprises the reactive component that is used to stablize self-dispersion type dispersing of pigments state, and to record reactive black dynamic surface tension 30 milliseconds of life-spans by maximum bubble pressure method be more than the 41mN/m.In addition, for the homogeneity of improving colored solid image and suppress black print through recording medium, require reactive China ink according to the present invention to have the dynamic surface tension character that is described below 500 milliseconds of life-spans to its back side (print through).

When using common paper as recording medium, in order to improve the picture quality of full-colour image, the homogeneity height of colored solid image importantly.Yet especially, the wetting properties of common paper is often inhomogeneous, so when common paper was used as recording medium, the coloured material in the color ink may not be present on the recording medium equably in some cases.When the China ink with aforesaid dynamic surface tension character when having reactive color ink, after China ink is administered to recording medium the dynamic surface tension of the China ink of 30 milliseconds time point up to 41mN/m more than.Therefore, do not cause that China ink infiltrates recording medium inside (thickness direction of recording medium), so can not reach the homogeneity in the colored solid image in some cases.Thus, the inventor studies.As a result, find: in order to reach the purpose of good homogeneity in the solid image of colour, the dynamic surface tension that reactive China ink requires to have 500 milliseconds of life-spans is below the 38mN/m.

Below description is limited to the importance of dynamic surface tension of the reactive China ink in 500 milliseconds of life-spans.As the result of inventor's research, found between the dynamic surface tension in 500 milliseconds of life-spans, to show the strongest dependency that promptly, this dynamic surface tension is an essential factor at the unhomogeneity and the reactive China ink of the solid image of colour.The inventor thinks that the strong correlation of reactive China ink between the unhomogeneity of the dynamic surface tension value in 500 milliseconds of life-spans and colored solid image hints the following fact.More specifically, from the time water influence of evaporation up to that reactive China ink is administered to recording medium by China ink cause associate or accumulative to finish the time that coloured material is affixed to recording medium simultaneously be extremely several thousand milliseconds of about hundreds of milliseconds.At this moment, think that the dynamic surface tension of reactive China ink 500 milliseconds of life-spans has a significant impact the speed that coloured material is affixed to recording medium.Think that coloured material is affixed to the homogeneity that balance between the gathering of the speed of recording medium and coloured material determines colored solid image.

Based on above-mentioned consideration, when reactive China ink is 38mN/m when following at the dynamic surface tension in 500 milliseconds of life-spans, the easy wetting recording medium of reactive China ink, thus think that China ink evenly infiltrates in the recording medium, and coloured material is affixed to recording medium equably.On the other hand, when reactive black dynamic surface tension 500 milliseconds of life-spans surpassed 38mN/m, reactive China ink remained on the state that is difficult to moistening recording medium, so think that coloured material causes uneven set on recording medium.

Yet, if reactive black dynamic surface tension 500 milliseconds of life-spans is low excessively, particularly being lower than 28mN/m, the perviousness that China ink enters in the recording medium becomes excessive.As a result, especially common paper is being used as under the situation of recording medium, the black recording medium inside (thickness direction of recording medium) of infiltrating easily, therefore print through promptly may take place to the recording medium back side in black possibility print through in some cases.Thus, requiring the dynamic surface tension of reactive China ink 500 milliseconds of life-spans is more than the 28mN/m.

[in the upper limit of the dynamic surface tension in 30 milliseconds of life-spans]

If reactive China ink is too high at the dynamic surface tension in 30 milliseconds of life-spans, particularly surpass 51mN/m, it is consuming time oversize that such China ink infiltrates recording medium.As a result, this China ink is in the expansion of recording medium surface, and therefore the character quality that is formed by this reactivity China ink in some cases may reduce.Therefore, reactive China ink is below the preferred 51mN/m of the dynamic surface tension in 30 milliseconds of life-spans.

＜China ink 〉

For various China inks according to the present invention, the feature of each component of China ink and this China ink of composition will be described below.

[reactive China ink]

Reactive China ink must comprise the reactive component that is used for stable pigments black ink self-dispersion type dispersing of pigments state and have following dynamic surface tension character.Reactive China ink must have dynamic surface tension 30 milliseconds of life-spans be more than the 41mN/m and the dynamic surface tension in 500 milliseconds of life-spans be more than the 28mN/m to 38mN/m.As mentioned above, reactive China ink is below the preferred 51mN/m of the dynamic surface tension in 30 milliseconds of life-spans.

In the present invention, going to be defined as and satisfy following modes (1) or (2) the self-dispersion type pigment in the pigment black ink.At first prepare mixed ink by equal-volume hybrid reaction China ink and pigment black ink.At this moment, to go to be defined as satisfied: the viscosity C that (1) occurs in the gathering of self-dispersion type pigment in the mixed ink or sedimentary pattern or (2) mixed ink satisfies the pattern of following relationship: C＞((A+B)/2) * 1.2, wherein A is the viscosity of reactive China ink, and B is the viscosity of pigment black ink.In addition, this viscosity is the value of measuring down at normal temperature (25 ℃), and its unit is mPas.Particularly, pattern (1) or (2) for example can be following modes (A), (B), (C) or (D).

Pattern (A): the self-dispersion type pigment in the pigment black ink has anionic group, and reactive China ink comprises cationic components as reactive component.In the case, when hybrid pigment black ink and reactive China ink, the gathering of pigment or the viscosity of precipitation or mixed ink to remove to stablize this dispersing of pigments state, therefore take place and increase in the anionic group reaction of cationic components in the reactive China ink and the self-dispersion type pigment in the pigment black ink.

As cationic components, can use for example polyvalent metal.Be used for comprising and for example in China ink, comprise polyvalent metal salt in the concrete mode that China ink comprises polyvalent metal.In addition, this polyvalent metal salt is present in the China ink with polyvalent metal ion and negatively charged ion.Yet, in the present invention, this information slip be shown in China ink, comprise polyvalent metal.The concrete preferred embodiment of polyvalent metal ion comprises Mg ²⁺, Ca ²⁺, Cu ²⁺, Co ²⁺, Ni ²⁺, Fe ²⁺, La ³⁺, Nd ³⁺, Y ³⁺And Al ³⁺Anionic specific examples comprises inorganic acid ion such as NO ₃ ^-, SO ₄ ^2-And Cl ^-, organic acid ion such as CH ₃COO ^-In the present invention, based on the package stability and the undissolved viewpoint of member (for example constituting the black stream of ink jet recording device) that requires to contact of the reactive China ink of gained, the especially preferred Mg that uses in the above-mentioned polyvalent metal ion with reactive China ink ²⁺Based on deliquescent viewpoint, preferably use the NO in the above-mentioned negatively charged ion ₃ ^-, SO ₄ ^2-, Cl ^-And CH ₃COO ^-, especially preferably use NO ₃ ^-, SO ₄ ^2-And CH ₃COO ^-, this is because the solvability of these negatively charged ion in water is good.More than the preferred 0.01 quality % of the content (quality %) of polyvalent metal in reactive China ink to 10.0 quality %, based on the total mass of China ink.When the form with polyvalent metal salt comprised, to 20.0 quality %, more preferably 0.2 quality % was above to 15.0 quality %, based on the total mass of China ink more than the preferred 0.1 quality % of the content (quality %) of polyvalent metal salt in reactive China ink.

Pattern (B): the self-dispersion type pigment in the pigment black ink has cation group, and reactive China ink comprises anionic group as reactive component.In the case, when hybrid pigment black ink and reactive China ink, the gathering of pigment or the viscosity of precipitation or mixed ink to remove to stablize this dispersing of pigments state, therefore take place and increase in the cation group reaction of anionic group in the reactive China ink and self-dispersion type pigment.

Pattern (C): when pH3 to 7, the self-dispersion type pigment stable dispersion in the pigment black ink is controlled at 8 to 11 with reactive black pH.In the case, when hybrid pigment black ink and reactive China ink, the pH of pigment black ink raises to go the dispersion state of stable pigments, therefore the gathering or the precipitation of pigment take place, or the viscosity of mixed ink increases.

Pattern (D): when pH7 to 11, the self-dispersion type pigment stable dispersion in the pigment black ink is controlled at 3 to 6 with reactive black pH.In the case, when hybrid pigment black ink and reactive China ink, the pH that reduces the pigment black ink therefore the gathering or the precipitation of pigment take place, or the viscosity of mixed ink increases to go the dispersion state of stable pigments.

(coloured material)

Even when reactive China ink for the China ink that do not contain coloured material or when containing coloured material black, also can reach effect of the present invention.Under the situation of the reactive China ink that contains coloured material, the coloured material in the reactive China ink can be selected from known coloured material or new synthetic coloured material suitably.More than the preferred 0.05 quality % of the content (quality %) of coloured material in reactive China ink to 15.0 quality %, based on the total mass of China ink.

Coloured material useful in reactive China ink is mentioned by following tone.Need not explanation, the invention is not restricted to these coloured materials.

(yellow coloring material)

C.I. directly yellow: 8,11,12,27,28,33,39,44,50,58,85,86,87,88,89,98,100,110,132 and 173; With the C.I. turmeric yellow: 1,3,7,11,17,23,25,29,36,38,40,42,44,76,98 and 99.

(cyan coloured material)

C.I. directly red: 2,4,9,11,20,23,24,31,39,46,62,75,79,80,83,89,95,197,201,218,220,224,225,226,227,228,229 and 230; C.I. Xylene Red: 6,8,9,13,14,18,26,27,32,35,42,51,52,80,83,87,89,92,106,114,115,133,134,145,158,198,249,265 and 289; C.I. edible red: 87,92 and 94; Directly purple with C.I.: 107.

(cyan coloured material)

C.I. sun blue: 1,15,22,25,41,76,77,80,86,90,98,106,108,120,158,163,168,199,226 and 307; With the C.I. acid blue: 1,7,9,15,22,23,25,29,40,43,59,62,74,78,80,90,100,102,104,112,117,127,138,158,161,203,204,221 and 244.

(black colorant material)

C.I. directly black: 17,19,22,31,32,51,62,71,74,112,113,154,168 and 195; C.I. erie black: 2,48,51,52,110,115 and 156; C.I. edible black: 1 and 2.

(other coloured materials)

In the present invention, as required, so-called specific redness, green and blue color ink can be used with the China ink of above-mentioned tone.The specific examples of useful coloured material is as described below in these China inks.Need not explanation, the invention is not restricted to these coloured materials.

C.I. von Muller's indicator: 7,8,10,12,24,33,56,67,74,88,94,116 and 142; C.I. Xylene Red: 111,114,266 and 374; C.I. direct orange: 26,29,34,39,57,102 and 118; C.I. edible orange: 3; C.I. reaction is orange: 1,4,5,7,12,13,14,15,16,20,29,30,84 and 107; C.I. DISPERSE ORANGE 30 200: 1,3,11,13,20,25,29,30,31,32,47,55 and 56; C.I. acid green: 1,3,5,6,9,12,15,16,19,21,25,28,81 and 84; C.I. sun green: 26,59 and 67; C.I. edible green: 3; C.I. react green: 5,6,12,19 and 21; C.I. Disperse Green: 6 and 9; C.I. acid blue: 62,80,83,90,104,112,113,142,203,204,221 and 244; C.I. reaction is blue: 49; C.I. acid violet: 17,19,48,49,54 and 129; C.I. directly purple: 9,35,47,51,66,93,95 and 99; C.I. reaction is purple: 1,2,4,5,6,8,9,22,34 and 36; With the C.I. 63 DISPERSE Violet 63: 1,4,8,23,26,28,31,33,35,38,48 and 56.

(tensio-active agent)

Reactive China ink preferably comprises tensio-active agent as permeate agent.Require to regulate prepared China ink to have above-mentioned change aspect the dynamic surface tension.As this type of tensio-active agent, can use and for example descend surfactant.Following tensio-active agent can use separately or with its arbitrary combination.

(nonionogenic tenside)

Voranol EP 2001, polyoxyethylene fatty acid ester, polyoxyethylene alkyl phenyl ether, polyoxyethylene/polyoxypropylene block copolymers, fatty diglycollic amide and acetylenediol compound.

(anion surfactant)

Polyoxyethylene alkyl ether sulfate salt, Voranol EP 2001 sulfonate, polyoxyethylene alkylphenyl ether sulfate salt, polyoxyethylene alkyl phenyl ether sulfonate, alpha-sulfo fatty acid ester salt, alkylbenzene sulfonate, alkylphenol sulfonate, sulfonated alkyl naphathalene, alkyl tetrahydro naphthalenesulfonate (alkyl tetralinsulfonic acid salts) and dialkyl sulfosuccinates.

(cats product)

Alkyl trimethyl ammonium salt and dialkyl dimethyl ammonium chloride.

(amphoterics)

The alkyl carboxyl trimethyl-glycine.

(other tensio-active agents)

Fluorochemical surfactant and silicone surfactant.

In the present invention, require the conditioned reaction China ink to have above-mentioned dynamic surface tension character.By using one or more above-mentioned tensio-active agents, can realize the conditioned reaction China ink so that have above-mentioned dynamic surface tension character to regulate the dynamic surface tension of China ink.

In the present invention, especially preferably use the dynamic surface tension of nonionogenic tenside conditioned reaction China ink, preferred Voranol EP 2001 in above-mentioned tensio-active agent.Under the situation of using this type of tensio-active agent, to 3.0 quality %, more preferably 0.5 quality % is above to 2.0 quality %, based on the total mass of China ink more than the preferred 0.10 quality % of the content (quality %) of tensio-active agent in reactive China ink.If this content is lower than 0.10 quality %, be not enough to reach the member of the black stream of moistening formation ink jet recording device, so jetting stability may reduce in some cases.If this content surpasses 3.0 quality %, when evaporating near the jet orifice of the water in this China ink at ink jet recording device, it is too high that the content of tensio-active agent becomes, and therefore black in some cases viscosity may locally increase, thereby reduces this black jetting stability.

In the present invention, especially preferred Voranol EP 2001 is for being selected from by the tensio-active agent of following general formula (1) expression and at least a by the tensio-active agent of following general formula (2) expression.Along with the change in life-span, the China ink that comprises these tensio-active agents causes the big change of dynamic surface tension, and therefore especially preferred this type of China ink suppresses bleeding or color ununiformity and reaches high image quality to reach simultaneously.

General formula (1)

In general formula (1), a, m and n represent the integer more than 1 independently of one another, and m+n represents integer 14 to 20.

General formula (2)

In general formula (2), b, x and y represent the integer more than 1 independently of one another, and x+y represents integer 12 to 21.

When using the tensio-active agent of being represented by general formula (1) or general formula (2), the preferred 0.30 quality % of the content of tensio-active agent (quality %) is above to 2.0 quality %, and more preferably 0.75 quality % is above to 1.5 quality %, based on the total mass of China ink.This content is controlled in the above-mentioned scope, thereby can reaches inhibition and high image quality simultaneously, and can reach good jetting stability bleeding or color ununiformity.

In the present invention, the HLB value of the tensio-active agent of measuring by the Griffin method especially preferred more than 12.0 to below 16.5.The Griffin method is the method that is used for and molecular weight calculating HLB value heavy according to (1) the surfactants based hydrophilic radical formula that establishes an equation down.

HLB=20 * (formula of the hydrophilic radical of tensio-active agent is heavy)/(molecular weight of tensio-active agent) (1)

If the HLB value is lower than 12.0, when China ink is stored, because its low excessively wetting ability can not keep the state of surfactant dissolves in China ink in some cases.On the other hand, if the HLB value surpasses 16.5,, may be difficult to reduce the dynamic surface tension of gained China ink in some cases 500 milliseconds of life-spans because the wetting ability of this tensio-active agent is too high.

(aqueous medium)

Reactive black preferred package aquosity medium, this aqueous medium is the mixed solvent of water and water-soluble organic compounds.Water-soluble organic compounds can be used for according in the China ink of the present invention arbitrarily, as long as this China ink is adjusted to and has above-mentioned dynamic surface tension character.To 50.0 quality %, more preferably 3.0 quality % are above to 40.0 quality %, based on the total mass of China ink more than the preferred 1.0 quality % of the content (quality %) of water-soluble organic compounds in China ink.

As water-soluble organic compounds, specifically can use for example following compounds: have the alcohol of 1 to 6 carbon atom, for example ethanol, 2-propyl alcohol, propyl carbinol, isopropylcarbinol, amylalcohol and hexanol; Carboxylic acid amide, N for example, dinethylformamide and N,N-dimethylacetamide; Ketone or keto-alcohol, for example acetone, methylethylketone and 2-methyl-2-hydroxyl penta-4-ketone; Cyclic ethers, for example tetrahydrofuran (THF) is with diox; Aklylene glycol, for example ethylene glycol, glycol ether, triglycol, Tetraglycol 99,1,2-or 1, ammediol, 1,2-or 1,4-butyleneglycol and polyoxyethylene glycol; Polyvalent alcohol, for example glycerine, 1,3 butylene glycol, 1,2-or 1,5-pentanediol, 1,2-or 1,6-hexylene glycol, 2-methyl isophthalic acid, ammediol and 1,2,6-hexanetriol; Polyol alkyl ether, for example glycol monomethyl methyl (or ethyl) ether, diglycol monotertiary methyl (or ethyl) ether and triglycol list ethyl (or butyl) ether; Heterogeneous ring compound, for example 2-Pyrrolidone, N-N-methyl-2-2-pyrrolidone N-, 1,3-dimethyl-2-imidazolone and N-methylmorpholine; And sulfocompound, for example dimethyl sulfoxide (DMSO) and thiodiglycol.

As water, preferably use deionized water (ion exchanged water).In order to provide China ink to be suitable for the stable China ink that sprays and suppress the viscosity that jet orifice stops up as having, more than the preferred 50.0 quality % of the content (quality %) of water in reactive China ink to 95.0 quality %, based on the total mass of China ink.

(other components)

In order to keep the moisture retention of China ink, except that said components, reactive China ink can comprise moisture retention compound such as urea, urea derivatives, TriMethylolPropane(TMP) and trimethylolethane.To 20.0 quality %, more preferably 3.0 quality % are above to 10.0 quality %, based on the total mass of China ink more than the preferred 0.1 quality % of the content (quality %) of moisture retention compound in reactive China ink.For the reactive China ink with required physical property values is provided, except that said components, reactive China ink can comprise all cpds as required.Particularly, for example can comprise various additives such as pH regulator agent, rust-preventive agent, sanitas, mould inhibitor, antioxidant, anti-reductive agent, evaporation accelerators, sequestrant and water-soluble polymers.

(physical properties of China ink)

In the present invention, the preferred 20mN/m of static surface tension of reactive China ink is above to 40mN/m, and more preferably 25mN/m is above to 35mN/m.

[pigment black ink]

(coloured material)

In the present invention, the pigment that requires to be used for the pigment black ink is self-dispersion type pigment.In the present invention, this self-dispersion type pigment be at least a hydrophilic radical directly or be bonded to the pigment of its particle surface by another atomic group.Next will describe this pigment in detail.The pigment black ink that comprises self-dispersion type pigment is used with above-mentioned reactive China ink, thereby the image with high-level picture quality that requires in recent years can be provided, and promptly wherein effectively suppresses the image that bleeding or color ununiformity take place.The inventor thinks that reason is as follows.With any other pigment, for example resin dispersion pigment is compared, and the pigment black ink that comprises self-dispersion type pigment causes that when contacting with reactive China ink pigment assembles quickly, thereby can reach above-mentioned effect more significantly.

Be used in the especially preferred self-dispersion type carbon black of self-dispersion type pigment in the pigment black ink of the present invention.In addition, in the pigment black ink,, except self-dispersion type pigment, also can use this dyestuff of mentioning as the coloured material that is used for reactive China ink for the purpose of color adaptation.To 15.0 quality %, more preferably 1.0 quality % are above to 10.0 quality %, based on the total mass of China ink more than the preferred 0.1 quality % of the content (quality %) of self-dispersion type pigment in the pigment black ink.

(carbon black)

As the pigment that is used in the pigment black ink, mention carbon black.Spendable sooty example comprises furnace black, dim, acetylene black and channel black.Particularly, for example can use the following carbon black products that is obtained commercially.These pigment can use separately or with its arbitrary combination.Need not explanation, the invention is not restricted to these products.

Raven:7000,5750,5250,5000 ULTRA, 3500,2000,1500,1250,1200,1190 ULTRA-II, 1170 and 1255 (being the product of Columbian Carbon Co. all); Black Pearls L, Regal:400R, 300R and 660R, Mogul L, Monarch:700,800,880,900,1000,1100,1300,1400 and 2000, and Valcan XC-72R (all being the product of CABOTCO.); Color Black:FW1, FW2, FW2V, FW18, FW200, S150, S160 and S170, Printex:35, U, V, 140U and 140V, and Special Black:6,5,4A and 4 (all being the product of Degussa AG); No.25, No.33, No.40, No.47, No.52, No.900, No.2300, MCF-88, MA600, MA7, MA8 and MA100 (all being the product of MITSUBISHI CHEMICALCORPORATION).

Also can use freshly prepd carbon black for the present invention.In addition, can use magnetic fine particle as magnetite and ferrite and titanium to deceive, and not be subject to carbon black.

(self-dispersion type pigment)

In the present invention, at least a hydrophilic radical directly or by another atomic group (R-) is bonded to the self-dispersion type pigment of its particle surface, can be used as above-mentioned carbon black (hereinafter being also referred to as pigment).Use this self-dispersion type pigment, thereby need not to add the dispersion agent that is used at the aqueous medium dispersed color of forming China ink.Certainly, if necessary, polymeric dispersant can use with self-dispersion type pigment.

The specific examples that is bonded to the hydrophilic radical on pigment particles surface comprises-COO (M ₁) ,-SO ₃(M ₁) ,-PO ₃H (M ₁) ,-PO ₃(M ₁) ₂With-(COO (M ₁)) _nIn following formula, " M ₁" be hydrogen atom, basic metal, ammonium or organic ammonium, n is the integer more than 2.Described another atomic group (R-) can be the phenylene of alkylidene group, replacement or non-replacement with 1 to 12 carbon atom or the naphthylidene of replacement or non-replacement.Need not explanation, the invention is not restricted to these groups.The form of the hydrophilic radical in the China ink can be the arbitrary form that is in the part disassociation state or the state that all dissociates.In the present invention, especially preferred use obtain by the diazo coupling method and partly have-R-(COOM at compound ₁) _nThe compound of unit structure is bonded to the pigment on pigment particles surface.

For be bonded to the pigment particles surface-R-, next-door neighbour bonding-(COOM ₁) the preferred bonding of the carbon bond-(COOM of carbon atom ₁).Also preferred n is 2, and R is C ₆H ₃In addition, be bonded to the pigment particles surface-situation of R-under, with bonding-(COOM ₁) carbon bond bonding-(COOM of carbon atom next-door neighbour ₁) two or more carbon atoms adjacent one another are of meaning among the R all have-(COOM ₁) group.Particularly, this means the structure that has as by following general formula (3) expression.In the present invention, the preferred use by the group bonding of following general formula (3) expression self-dispersion type pigment to the pigment particles surface.

General formula (3)

For the pigment black ink ,-R-(COOM ₁) _nGroup preferably is bonded in the pigment particles surface with higher density.Particularly, the hydrophilic radical density preference on pigment particles surface is as 2.00 μ mol/m ²More than.In addition, in the present invention, the density of hydrophilic radical is subjected to the specific surface area and the very big influence of structure of functional groups that is bonded to the pigment particles surface of pigment in the pigment particles, so hydrophilic radical density is not limited to this scope.The preferred 4.0 μ mol/m of the upper limit of the hydrophilic radical density on pigment particles surface ²Below.

In the pigment black ink, M ₁Especially be preferably ammonium, this is because reach better water fastness.Think that this is owing under the condition when this China ink is applied to recording medium, this ammonium decomposes and vaporized ammonia, and the hydrophilic radical that is bonded to the pigment particles surface becomes H type (acid type), thereby reduces wetting ability.M ₁For the self-dispersion type pigment of ammonium can obtain according to the following step.For example, make wherein M ₁For alkali-metal self-dispersion type pigment carries out ion-exchange to replace M by ammonium ₁Perhaps, add acid, add ammonium hydroxide then with M to obtain the H type ₁Be converted into ammonium.

(salt)

The preferred saliferous of pigment black ink, thus the gathering of pigment on recording medium promoted, therefore can stablize and reach effect of the present invention, and irrelevant with the kind of recording medium.

The form of the salt in the pigment black ink can be the arbitrary form that is in its part dissociative state or its whole dissociative states.In addition, salt is present in the China ink as metal ion and negatively charged ion.Yet, in the present invention, this information slip be shown in China ink, comprise salt.

The specific examples that can be used for the salt of pigment black ink comprises (M ₂) NO ₃, CH ₃COO (M ₂), C ₆H ₅COO (M ₂), C ₂H ₄(COO (M ₂)) ₂, C ₆H ₄(COO (M ₂)) ₂(M ₂) ₂SO ₄" M in the formula ₂" be hydrogen atom, basic metal, ammonium or organic ammonium.Alkali-metal example comprises lithium, sodium and potassium.The example of organic ammonium comprises acetyl amido, benzamido, methylamino, butyl amino, diethylamino and phenyl amino.Need not explanation, the invention is not restricted to these.

The content of salt is only required and is included in and can fully reaches in the scope of effect of the present invention in the pigment black ink.Particularly, the preferred 0.05 quality % of the content of salt (quality %) is above to 10.0 quality %, based on the total mass of China ink.If this content is lower than 0.05 quality %, can not reach effect of the present invention in some cases.If this content surpasses 10.0 quality %, the package stability of gained China ink may deterioration in some cases.

(aqueous medium)

Pigment black ink preferred package aquosity medium, this aqueous medium is the mixed solvent of water and water-soluble organic compounds.As water, preferably use deionized water (ion exchanged water).More than the preferred 50.0 quality % of the content (quality %) of water in the pigment black ink to 95.0 quality %, based on the total mass of China ink.

This water-soluble organic compounds especially is preferably has the compound that suppresses black exsiccant effect.More than the preferred 3.0 quality % of the content (quality %) of water-soluble organic compounds in the pigment black ink to 50.0 quality %, based on the total mass of China ink.For example, specifically can use following water-soluble organic compounds.Following water-soluble organic compounds can use separately or with its arbitrary combination.

Alcohol with 1 to 6 carbon atom, for example ethanol, 2-propyl alcohol, propyl carbinol, isopropylcarbinol, the trimethyl carbinol, amylalcohol and hexanol; Carboxylic acid amide, N for example, dinethylformamide and N,N-dimethylacetamide; Ketone or keto-alcohol, for example acetone, methylethylketone and 2-methyl-2-hydroxyl penta-4-ketone; Cyclic ethers, for example tetrahydrofuran (THF) is with diox; Polyvalent alcohol, for example glycerine, ethylene glycol, glycol ether, triglycol, Tetraglycol 99,1,2-or 1, ammediol, 1,2-or 1,4-butyleneglycol and polyoxyethylene glycol; Polyvalent alcohol, 1,3 butylene glycol, 1 for example, 2-or 1,5-pentanediol, 1,2-or 1,6-hexylene glycol, dithioglycol, 2-methyl isophthalic acid, ammediol, 1,2,6-hexanetriol and TriMethylolPropane(TMP); Polyol alkyl ether, for example glycol monomethyl methyl (or ethyl) ether, diglycol monotertiary methyl (or ethyl) ether and triglycol list ethyl (or butyl) ether; Heterogeneous ring compound, for example 2-Pyrrolidone, N-N-methyl-2-2-pyrrolidone N-, 1,3-dimethyl-2-imidazolone and N-methylmorpholine; And sulfocompound, for example dimethyl sulfoxide (DMSO).

(other components)

In order to keep the moisture retention of China ink, except that said components, this pigment black ink can comprise moisture retention compound such as urea, urea derivatives, TriMethylolPropane(TMP) and trimethylolethane.To 20.0 quality %, more preferably 3.0 quality % are above to 10.0 quality %, based on the total mass of China ink more than the preferred 0.1 quality % of the content (quality %) of moisture retention compound in the pigment black ink.Except said components, for required physical property values being provided for the pigment black ink, this pigment black ink can comprise additive such as tensio-active agent, pH regulator agent, defoamer, rust-preventive agent, sanitas, mould inhibitor, antioxidant, anti-reductive agent, evaporation accelerators and sequestrant as required.

(physical properties of China ink)

In the present invention, the preferred 30mN/m of the static surface tension of pigment black ink is above to 60mN/m, and more preferably 35mN/m is above to 50mN/m.

[non-reacted China ink]

In the present invention, except above-mentioned reactive China ink and pigment black ink, the other China ink of use also capable of being combined.This other China ink comprises and does not contain for example China ink of polyvalent metal (non-reacted China ink) among the present invention, promptly not with the China ink of pigment black ink reaction.The coloured material that is used for non-reacted China ink can be selected from known coloured material and new synthetic coloured material suitably.Particularly, can use as useful those of the coloured material that is used for reactive China ink.More than the preferred 0.05 quality % of the content (quality %) of coloured material in non-reacted China ink to 15.0 quality %, based on the total mass of China ink.As the additive of aqueous medium and non-reacted China ink, can use and identical medium and additive in above-mentioned reactive China ink and pigment inks.

＜complete China ink 〉

Complete China ink according to the present invention has multiple China ink, and wherein this complete China ink has above-mentioned aqueous ink and pigment black ink.This complete China ink can further have at least a of above-mentioned non-reacted China ink and any other China inks.Complete China ink among the present invention comprises the form of print cartridge of the multiple China ink of independent storage or the form of the print cartridge by making up a plurality of integrated formation of black reservoir of storing multiple China ink respectively.In addition, print cartridge can have the structure of integrated extraly formation record-header.Constitute and independently to store the print cartridge of multiple China ink, also can be included in according in the complete China ink of the present invention so that be removably mounted on form on the ink jet recording device.Under any circumstance, only need constitute in reactive at least the mode black and use capable of being combined of pigment black ink by complete China ink according to the present invention, therefore complete China ink is not limited to above-mentioned pattern, and can be arbitrary patterns.

＜image forming method and image forming apparatus 〉

Contain the black ink of self-dispersion type pigment and the image forming method that at least a aqueous ink forms image according to image forming method of the present invention for use, wherein with above-mentioned pigment black ink and above-mentioned aqueous ink as this black ink and aqueous ink, and image forms in the mode that the image of the image that forms with the pigment black ink and the formation of use China ink overlaps each other in subregion at least.

Contain the black ink of self-dispersion type pigment and the image forming apparatus that at least a aqueous ink forms image according to image forming apparatus of the present invention for use, wherein above-mentioned pigment black ink and above-mentioned aqueous ink are used as this black ink and aqueous ink, and this equipment has the unit that is used to form image, and the mode that the image that this image forms with the image that forms with the pigment black ink and use China ink overlaps each other in subregion at least forms.

Use above-mentioned reactive China ink and pigment black ink to carry out the document image forming device as being applicable to, will be described the ink jet recording device that can carry out bidirectional record with reference to Fig. 1 and 2.

The schematically illustrated exemplary ink jet recording device of Fig. 1.Chassis (chassis) 1 is made of a plurality of plate-shape metal members with redetermined rigidity, and forms the skeleton of ink jet recording device.In the chassis, introduce the feeding portion (feedsection) 2 that is used for the feeding recording medium, be used for recording medium is guided to booking situation position and the transport unit 4 that guides to discharge portion 3, be used on recording medium, carrying out the record portion of booking situation, and the record-header answer portion 5 that is used for record portion is replied operation.Record portion has the bearing 7 that can scan support along bearing axle 6, sets the flap 9 that bar 8 is removably mounted on the head cartridge 10 on the bearing 7 and is used for this head cartridge is navigated to the predetermined position by record-header.An end that contacts flexible print cable (hereafter is " contact FPC ") 11 is connected to another junction surface of the bearing 7 relative with head cartridge 10.The contact part 15 (referring to Fig. 2) that is formed on the end of contact FPC11 electrically contacts with contact part 15, and contact part 15 is for being arranged on the external signal input terminal on the head cartridge 10, to carry out various transmission of Information and to provide power supply to head cartridge 10.

When forming image, bearing 7 configuration record head boxes 10 in head cartridge 10, form the position at required image and introduce record-header, thus based on the various information that receive by contact part 15, by spraying China ink from record-header at the enterprising line item of recording medium.Particularly, bearing 7 is alternately repeated in the subscan that column direction transmits recording medium by main-scanning and the transport unit 4 that record-header writes down along 6 scannings of bearing axle simultaneously at line direction, thereby on recording medium, form image.At this moment, image is the single pass record by record-header at the image forming method that a main-scanning of the unit area of recording medium forms, and this single pass is recorded in the working direction of main-scanning and image forming method that the direction of retreat both direction all carries out is the single pass bidirectional record.N scanning by record-header is that n is all over record (n is more than 1) at the image forming method of the unit area formation image of recording medium.Unit area means a pixel or band (band), and unit area can be preset as various zones as required.At this, a pixel refers to the pixel corresponding to resolving power, and band means the image-region that the single pass by record-header forms.Based on the viewpoint that reaches effect of the present invention, especially preferred composing images formation method and image forming apparatus are to comprise the single pass bidirectional record.

The schematically illustrated exemplary record of a Fig. 2 box 10.At this, will use the situation of three kinds of colour ink box pigment black ink to provide description as an example.At least a of three kinds of color ink is according to reactive China ink of the present invention.Based on the recording signal that receives by contact part 15 from the recording unit main body, head cartridge 10 sprays China ink from the jet orifice row 14 of the record-header 12 that is used for the pigment black ink and the record-header 13 same jet orifices row that are provided with that are used for color ink, in addition, though below three kinds of color ink are described, the quantity of color ink is not limited thereto, the form and aspect of the quantity of China ink and China ink can suitably be preset, as long as at least a of color ink is according to reactive China ink of the present invention.

As record-header, mention in China ink by the heat energy effect causing that film boiling sprays the record-header of Bubble-Jet (trade mark) system of China ink.Routine with respect to ink gun constitutes and principle, uses ultimate principle to be disclosed in for example United States Patent (USP) 4,723,129 and 4,740, and those of 796 are preferred.This system can be applicable to any in so-called type as required and the successive type.Yet, type is effective as required, this is because will put on the electric heating convertor corresponding to recorded information and at least a actuate signal that is rapidly heated that provides above film boiling, cause film boiling thereby produce heat energy with heat effect surface, therefore can man-to-man relation respond actuate signal and in China ink, form bubble at record-header.China ink sprays by jet orifice by the growth and the contraction of bubble.When this actuate signal applies with the form of pulse, this moment bubble growth and shrink and carry out suitably, therefore can reach the injection of the especially good China ink of responsiveness.More preferably use this pulse signal thus.

Except above-mentioned record-header, mention the record-header that sprays the system of China ink by the effect of mechanical energy.The record-header of this system is equipped with the nozzle with a plurality of nozzles and forms substrate, the piezoelectric that is provided with the nozzle subtend, the pressure generating equipment that is made of electro-conductive material and be filled in China ink around this pressure generating equipment.In this structure, make this pressure generating equipment displacement by applying voltage, thereby spray China ink.

Ink jet recording device can be record-header and separates the equipment of setting or the equipment of the inseparable ground integrated formation of these members with print cartridge.This print cartridge can be with record-header separably or inseparably with the integrated type that is installed on the bearing of record-header, or be arranged on the fixed position of ink jet recording device and China ink be fed to the type of record-header by black supply member such as pipe.When in print cartridge, being provided with when being used for that favourable negative pressure imposed on the structure of record-header, can preferably use down array structure.More specifically, the example comprises that absorption component is configured in the structure of the black reservoir of print cartridge, and has flexible storage China ink bag and the structure that is used at the internal volume dimension of this bag biassing force (biasing force) being imposed on the spring portion of bag.This ink jet recording device preferably uses successive type register system as mentioned above, but but the line printing type that the service recorder element is arranged corresponding to the whole width range of recording medium.

[embodiment]

Hereinafter, will the present invention more specifically be described by the following example, comparative example and reference example.Yet the present invention is not limited to these embodiment, unless exceed purport of the present invention.In addition, unless otherwise indicated, below " % " of Shi Yonging is based on quality.

＜preparation dispersible pigment dispersion 〉

In the 5g concentrated hydrochloric acid solution in being dissolved in 5.5g water, cooling off adding 1.5g 4-amino-1 under 5 ℃, 2-phthalic acid.The container that this solution will be housed then is placed in the ice bath, stirred solution, thus solution is remained on below 10 ℃ always, in this solution, add the solution that the 1.8g Sodium Nitrite is dissolved in gained in the water of 5 ℃ of 9g then.Continue to stir this solution after 15 minutes, adding while stirring that 6g has specific surface area 220m2/g and the DBP oil-absorption(number) is the carbon black of 105mL/100g.Then the mixture that obtains was continued to stir 15 minutes again.The gained slurry is being passed through filter paper (trade(brand)name: StandardFilter Paper No.2; The product of Advantec Co.) filter after, water thoroughly washs gained particle and dry in being controlled at 110 ℃ baking oven, thus preparation self-dispersion type carbon black.The self-dispersion type carbon black of gained is carried out ion-exchange to replace sodium ion by ammonium ion.Further water is joined in the above self-dispersion type carbon black that obtains and come disperse black carbon, so that provide the pigment concentration of 10 quality %, thus the preparation dispersion liquid.According to above-mentioned steps, obtain dispersible pigment dispersion, in this dispersible pigment dispersion ,-C ₆H ₃-(COONH ₄) ₂Group is incorporated into self-dispersion type carbon black particle surface, and this self-dispersion type carbon black dispersion is in water.

Measure the self-dispersion type sooty ionic group density of above preparation.As a result, this ionic group density is 3.1 μ mol/m ²The measuring method of the measurement ionic group density that use this moment is: measure the Na ion concentration in the self-dispersion type carbon black (sodium-salt type) that makes above by ionometer (TOA DKK manufacturing), this value is converted into the density of the ionic group in the self-dispersion type carbon black again.

The HLB value and the structure of＜tensio-active agent 〉

Measure the HLB value of tensio-active agent.Particularly, calculate the HLB value of main ingredient in each tensio-active agent according to Griffin method (establishing an equation (1) down).The results are shown in table 1.

HLB=20 * (formula of the hydrophilic radical of tensio-active agent is heavy)/(molecular weight of tensio-active agent) (1)

In table 1, the structure of the main ingredient of every kind of tensio-active agent, with value, or totally illustrate when the value of x, y, b and the x+y of this surfactant structure during corresponding to general formula (2) as m, n, a and the m+n of this surfactant structure during corresponding to general formula (1).

In table 1, EMALEX 1610, EMALEX 1615 and EMALEX 1825 are Nihon Emulsion Co., Ltd. the tensio-active agent of Sheng Chaning, NIKKOL BT-7 and NIKKOL BT-12 are Nikko Chemicals Co., Ltd. the tensio-active agent of Sheng Chaning, ACETYLENOL E100 is Kawaken Fine Chemicals Co., the tensio-active agent that Ltd. produces.

Table 1

＜preparation China ink 〉

Mix and fully stir and be shown in table 2 to 5 component, each mixture with gained, under pressure, filter strainer (Fuji Photo Film Co. for the pigment black ink by having aperture 3.0 μ m, Ltd. product), under pressure, filter micro-strainer (Fuji Photo Film Co. for other China inks by having aperture 0.2 μ m, Ltd. product), thus preparation China ink.In addition, table 2 to 5 in, EMALEX 1610, EMALEX1615 and EMALEX 1825 are Nihon Emulsion Co., Ltd. the tensio-active agent of Sheng Chaning, NIKKOL BT-7 and NIKKOL BT-12 are NikkoChemicals Co., Ltd. the tensio-active agent of Sheng Chaning, ACETYLENOL E100 is Kawaken Fine Chemicals Co., the tensio-active agent that Ltd. produces.

Table 2 (unit: %)

Table 3 (unit: %)

Table 4 (unit: %)

Table 5 (unit: %)

Reactivity between＜reactive China ink or non-reacted China ink and the pigment black ink 〉

Mix and fully stir the 20g pigment black ink that is shown in table 6 and the reactive China ink of 20g or non-reacted China ink, mixed ink is left standstill 24 hours then with the preparation mixed ink.Thereafter, the precipitation in the visual observation mixed ink and or the existence of aggregate so that reactivity is estimated.Evaluation result is shown in table 6.

Table 6

( ^*1) reactive China ink or non-reacted China ink.

From table 6, can understand combination pigment black ink and reactive China ink, reactive black R-1 to R-16 is the China ink of the dispersing of pigments state in the stable pigments black ink.

＜estimate

(measurement dynamic surface tension)

For reactive China ink of above each that obtains and non-reacted China ink, measure the dynamic surface tension of China ink when (1) 30 millisecond of life-span and (2) 500 milliseconds of life-spans.To measure equipment (the Bubble Pressure TesiometerBP2 of dynamic surface tension according to maximum bubble pressure method; Make by KRUSS) be used for this measurement.Evaluation result to dynamic surface tension is shown in table 7.

Table 7

(irregular colour in the solid black image is even)

Be used in combination first shown in the table 8 and use China ink and second use China ink, thereby form the solid black image, in this image forming method, use another kind of black with the overlapping zone that will use the pigment black ink by image forming method.To can carry out equipment that the ink jet recording device BJF850 (being made by Canon Inc.) of bidirectional record obtains as image forming apparatus by repacking.Four kinds of common paper Canon Extra, Canon OfficeMulti-Function Applications, EN100 and high color development common paper Superwhite Paper SW101 (all being the product of Canon Inc.) are used as recording medium.In addition, China ink being applied to every kind of recording medium uses black order and overlaps each other to use China ink and second according to table 8 described first.Carry out the formation of image by the single pass bidirectional record.The amount of application of 1/600 square feet China ink at this moment is controlled at the about 28ng of pigment black ink, to the about 4.5ng of other China inks.

For each image by using four kinds of recording mediums to obtain, visual observation is by the image of the record formation of advancing with by the difference between image color and the tone in the image that retreats record formation, estimating, thereby its mean value is considered as the evaluation result of color ununiformity in the solid black image.Relative A, B, C, D and 5 grades of E of being divided into of evaluation to the color ununiformity of embodiment 1 to 14, comparative example 1 to 7 and reference example 1.More specifically, by advancing the image that forms of record and be under the situation of the best by retreating the image color between the image that record forms and the difference situation of tone, the color ununiformity is chosen as A, by advancing the image that forms of record and be that color ununiformity under the poorest situation is chosen as E by the difference situation that retreats image color between the image that record forms and tone.As evaluation result, A in A, B, C, D and E 5 grades and B are defined as the acceptable degree of color ununiformity in the current required solid black image.Evaluation result is shown in table 8.

(bleeding resistance)

Form wherein with the solid black picture appraisal in the identical solid black image that forms adjoin the image of the solid image that forms with color ink.At this moment, mix and abundant stirring component shown below, each mixture of gained filters under pressure by the micro-strainer with aperture 0.2 μ m (FujiPhoto Film Co., the product of Ltd.), thereby prepare yellow non-reacted China ink, and should be used as color ink by China ink.The component that constitutes yellow ink is the C.I. acid yellow 23: 3.0 parts, glycerine: 5.0 parts, and 1,5-pentanediol: 10.0 parts, glycol ether: 5.0 parts, Acetylenol E100:1.0 part and water: 76.0 parts.To can carry out equipment that the ink jet recording device BJF850 (being made by Canon Inc.) of bidirectional record obtains as image forming apparatus by repacking.Four kinds of common paper Canon Extra, CanonOffice Multi-Function Applications, EN100 and high color development common paper Superwhite Paper SW101 (all being the product of Canon Inc.) are used as recording medium.Carrying out image by the single pass bidirectional record forms.The amount of application of per 1/600 square feet China ink at this moment is controlled at for the about 28ng of pigment black ink, for the about 4.5ng of non-reacted China ink.

For each image by using four kinds of recording mediums to obtain, between visual observation black and the coloured image bleeding of boundary member estimating, thereby its mean value is considered as the evaluation result of bleeding.Relative A, B and C three grades of being divided into of embodiment 1 to 14 with the bleeding resistance evaluation of comparative example 1 to 7 and reference example 1.More specifically, the bleeding resistance under the situation of bleeding is minimum and good image quality is chosen as A, with bleeding at most and the bleeding resistance under the situation of poor image quality be chosen as C.As evaluation result, A in A, B and C three grades and B are defined as the acceptable degree of current required bleeding resistance.Evaluation result is shown in table 8.

(homogeneity of colored solid image)

The China ink that is shown in table 8 right side by use forms colored solid image.At this moment, do not use the pigment black ink.To can carry out equipment that the ink jet recording device BJF850 (being made by Canon Inc.) of bidirectional record obtains as image forming apparatus by repacking.Four kinds of common paper Canon Extra, Canon Office Multi-FunctionApplications, EN100 and high color development common paper Superwhite PaperSW101 (all being the product of Canon Inc.) are used as recording medium.Carrying out image by the single pass bidirectional record forms.Per 1/600 square feet black amount of application of this moment is controlled at about 14ng.

For each image by using four kinds of recording mediums to obtain, the homogeneity of the colored solid image of visual observation to be estimating, thereby its mean value is considered as the evaluation result of homogeneity in the colored solid image.Relative A, B, C and four grades of D of being divided into of the homogeneity evaluation of the colored solid image of embodiment 1 to 14, comparative example 1 to 7 and reference example 1.More specifically, the homogeneity of the colored solid image under the situation of the solid image homogeneity of colour is the highest and good image quality is chosen as A, with the solid image homogeneity of colour minimum be chosen as D.As evaluation result, A in A, B, C and D 4 grades and B are defined as the acceptable degree of homogeneity in the current required colored solid image.Evaluation result is shown in table 8.

(color character quality)

The China ink that is shown in table 8 right hand one side by use forms the color character of 12 Gothic font.At this moment, do not use the pigment black ink.To can carry out equipment that the ink jet recording device BJF850 (being made by Canon Inc.) of bidirectional record obtains as image forming apparatus by repacking.Four kinds of common paper Canon Extra, Canon OfficeMulti-Function Applications, EN100 and high color development common paper Superwhite Paper SW101 (all being the product of Canon Inc.) are used as recording medium.Carrying out image by the single pass bidirectional record forms.Per 1/600 square feet black amount of application of this moment is controlled at about 18ng.

For each image by using four kinds of recording mediums to obtain, visual observation color character quality to be estimating, thereby its mean value is considered as the evaluation result of color character quality.Relative A and two grades of B of being divided into of the evaluation of the color character quality of embodiment 1 to 14, comparative example 1 to 7 and reference example 1.More specifically, the top-quality color character quality of color character is chosen as A, the color character quality is lower than A but also at the B that is chosen as of acceptable degree.Evaluation result is shown in table 8.

When the reactive China ink (R-16) that will use comparative example 7 in the part of the coloured image that forms on the recording medium when its back side is observed, print through has taken place.On the other hand, use to remove reactive black the reactive China ink (R-16) or using the back side of the part of the image that non-reacted China ink forms on recording medium that print through does not take place.

Although reference example embodiment of the present invention is described, should understands and the invention is not restricted to disclosed exemplary.The scope of appended claim should meet the most wide in range explanation to comprise this type of all improvement and equivalent configurations and function.

Claims (8)

1. aqueous ink, this aqueous ink is used with the black ink that comprises self-dispersion type pigment,

This aqueous ink comprises the reactive component that is used to stablize self-dispersion type colo(u)rant dispersion state,

Wherein, the dynamic surface tension of this aqueous ink 30 milliseconds of life-spans of being measured by maximum bubble pressure method is more than the 41mN/m, this aqueous ink the dynamic surface tension in 500 milliseconds of life-spans be more than the 28mN/m to 38mN/m.

2. aqueous ink according to claim 1, wherein, the dynamic surface tension of this aqueous ink 30 milliseconds of life-spans of being measured by maximum bubble pressure method is below the 51mN/m.

3. aqueous ink according to claim 1, wherein, this aqueous ink comprises Voranol EP 2001 as tensio-active agent.

4. aqueous ink according to claim 3, wherein this Voranol EP 2001 is for being selected from by the tensio-active agent of following general formula (1) expression and at least a by the tensio-active agent of following general formula (2) expression:

General formula (1):

Wherein a, m and n represent the integer more than 1 independently of one another, and m+n represents 14 to 20 integer;

General formula (2):

Wherein b, x and y represent the integer more than 1 independently of one another, and x+y represents 12 to 21 integer.

5. aqueous ink according to claim 1, wherein this reactive component is a polyvalent metal.

6. complete China ink, it comprises multiple China ink, and wherein this complete China ink comprises aqueous ink according to claim 1 and black ink according to claim 1.

7. image forming method, its use comprise the black ink of self-dispersion type pigment and at least a aqueous ink forming image,

Wherein this aqueous ink is an aqueous ink according to claim 1, and this black ink is a black ink according to claim 1,

This method comprises that the mode that the image that forms with image that forms with black ink and use China ink overlaps each other forms image in subregion at least.

8. image forming apparatus, its black ink and at least a aqueous ink that is used for comprising by use self-dispersion type pigment forms image,

Wherein this aqueous ink is an aqueous ink according to claim 1, and this black ink is a black ink according to claim 1,

This equipment comprises and is used for the unit that mode that the image that forms with the image that forms with black ink and use China ink overlaps each other in subregion at least forms image.

Images