CA1149613A - Heat sensitive recording sheet - Google Patents
Heat sensitive recording sheetInfo
- Publication number
- CA1149613A CA1149613A CA000354135A CA354135A CA1149613A CA 1149613 A CA1149613 A CA 1149613A CA 000354135 A CA000354135 A CA 000354135A CA 354135 A CA354135 A CA 354135A CA 1149613 A CA1149613 A CA 1149613A
- Authority
- CA
- Canada
- Prior art keywords
- sensitive recording
- recording sheet
- heat sensitive
- bis
- developer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
- B41M5/00—Duplicating or marking methods; Sheet materials for use therein
- B41M5/26—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used
- B41M5/30—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used using chemical colour formers
- B41M5/337—Additives; Binders
- B41M5/3375—Non-macromolecular compounds
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
- B41M5/00—Duplicating or marking methods; Sheet materials for use therein
- B41M5/26—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used
- B41M5/30—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used using chemical colour formers
- B41M5/333—Colour developing components therefor, e.g. acidic compounds
- B41M5/3333—Non-macromolecular compounds
- B41M5/3335—Compounds containing phenolic or carboxylic acid groups or metal salts thereof
- B41M5/3336—Sulfur compounds, e.g. sulfones, sulfides, sulfonamides
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S428/00—Stock material or miscellaneous articles
- Y10S428/913—Material designed to be responsive to temperature, light, moisture
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S428/00—Stock material or miscellaneous articles
- Y10S428/914—Transfer or decalcomania
Abstract
SPECIFICATION
Title of the Invention:
Heat Sensitive Recording Sheet Abstract of the Disclosure:
Heat sensitive recording sheet improved in light resistance and-water resistance, a developer contained therein being one or more than one of specified metal salts of 2,2'-bisphenolsulfide, 2,2'-bisphenolsulfoxide and 2,2'-bisphenolsulfone compounds, and the heat sensitive recording sheet may further contain a heat fusible material having a melting point of from 50° to 190°C.
Title of the Invention:
Heat Sensitive Recording Sheet Abstract of the Disclosure:
Heat sensitive recording sheet improved in light resistance and-water resistance, a developer contained therein being one or more than one of specified metal salts of 2,2'-bisphenolsulfide, 2,2'-bisphenolsulfoxide and 2,2'-bisphenolsulfone compounds, and the heat sensitive recording sheet may further contain a heat fusible material having a melting point of from 50° to 190°C.
Description
~ 61 3 This invention relates to an improved heat sensitive recording sheet containing a novel developer.
A so-called dye color development type heat sensitive recording sheet is well known in the art, according to which a coupler consisting of electron donative, color assuming compounds such as triphenylmethane series, fluoran series, phenothiazine series, auramine series, spiropyran series, and the like ~hereinafter simply referred to as coupler), and a developer consisting of a solid acid selected from clays such as activated clay, pAenol compounds, aromatic carboxylic acids, aromatic polyvalent metal salts, and the like, are brought into contact with each other by heating to obtain a developed color image by the application of the color reaction therebetween.
Generally, the heat sensitive recording sheet is required as conditions for performance thereof which the sheet should possess to be colorless or light colored itself, to have a fast developed color image as well as an excellent performance for color development immediately after the preparation of the sheet or after a long term storage of the sheet without lowering thereof, to be sufficiently stable to light or moistu~e, and further to be prepared economically. The developer for heat sensitive recording, which has already been proposed, and sheets coated with the developer have both merits and demerits from the standpoint of performance, and these sheets have such drawbacks that color develops prior to heating on reproduction
A so-called dye color development type heat sensitive recording sheet is well known in the art, according to which a coupler consisting of electron donative, color assuming compounds such as triphenylmethane series, fluoran series, phenothiazine series, auramine series, spiropyran series, and the like ~hereinafter simply referred to as coupler), and a developer consisting of a solid acid selected from clays such as activated clay, pAenol compounds, aromatic carboxylic acids, aromatic polyvalent metal salts, and the like, are brought into contact with each other by heating to obtain a developed color image by the application of the color reaction therebetween.
Generally, the heat sensitive recording sheet is required as conditions for performance thereof which the sheet should possess to be colorless or light colored itself, to have a fast developed color image as well as an excellent performance for color development immediately after the preparation of the sheet or after a long term storage of the sheet without lowering thereof, to be sufficiently stable to light or moistu~e, and further to be prepared economically. The developer for heat sensitive recording, which has already been proposed, and sheets coated with the developer have both merits and demerits from the standpoint of performance, and these sheets have such drawbacks that color develops prior to heating on reproduction
- 2 '~
~96~3 to produce blushing because two reactants are brought into contact with each other to be coated on a substrate, that they have poor storage stability of a developed image such as light resistance and water resistance, and that color does not develop instantly on heating, which demands ~urther an improved Aeat sensitive recording sheet.
The color development property by heating of 4,4'-isopropylidenediphenyl (bisphenol A~ exclusively used at present is of clear, but fastness properties to light of the developed color image are not satisfactory.
In accordance with the present invention, there is provided a heat sensitive recording sheet prepared by coating on a.sheet substrate, or by impregnating therein a coupler, developer, and binder, characterized in that said developer is one or more than one of the compounds represented by the general ~ormula (I) M
S ()n ~ (I) R R
where R represents hydrogen, an alkyl radi~al of from 1 to 12 ~ 9613 carbon atoms, a cycloalkyl radical of from 3 to 10 carbon atoms, an aralkyl radical of from 7 to 10 carbon atoms, and a phenyl radical, and may be identical to or different from each other, M represents polyvalent metals excepting for Group IA of the Periodic Table, n is zero, or an integer of 1 or 2.
The present invention further provides a heat sensitiv-e recording sheet which contains one or more than one of the compounds represented by the general ~ormula (I) as developer, and may further contain heat fusible materials which have a melting point of from 50 to 190C and is substantially colorless at room temperature. The heat sensitive recording sheet containing these heat fusible materials generally inc~eases more and more the rate of color development on heating, and lowers the temperature of color development.
Examples of the compounds represented by the general formula (I) include, but not to be limited thereto, zinc 2,2'-diphenolsulfide, nickel 2,2'-diphenolsulfone, zinc 2,2'-bis(p-cresol)sulfide, zinc 2,2'-bis(p-tert-butylphenol)sulfide, nickel 2,2'-bis(p-tert-butylphenol~sulfide, zinc 2,2'-bis(p-tert-butylphenol)sulfone, nickel 2,2'-bis~p-tert-butylphenol)sulfone, zinc 2,2'-bis(p-tert-amylphenol)sulfone, zinc 2,2'-bis~p-cyclohexyl)sulfide, zinc 2,2'-bis(p-cyclohexyl)sulfoxide, zinc 2,2'-bis(p-cyclohexyl)sulfone, nickel 2,2'-bis(p-cyclohexyl)sulfone,
~96~3 to produce blushing because two reactants are brought into contact with each other to be coated on a substrate, that they have poor storage stability of a developed image such as light resistance and water resistance, and that color does not develop instantly on heating, which demands ~urther an improved Aeat sensitive recording sheet.
The color development property by heating of 4,4'-isopropylidenediphenyl (bisphenol A~ exclusively used at present is of clear, but fastness properties to light of the developed color image are not satisfactory.
In accordance with the present invention, there is provided a heat sensitive recording sheet prepared by coating on a.sheet substrate, or by impregnating therein a coupler, developer, and binder, characterized in that said developer is one or more than one of the compounds represented by the general ~ormula (I) M
S ()n ~ (I) R R
where R represents hydrogen, an alkyl radi~al of from 1 to 12 ~ 9613 carbon atoms, a cycloalkyl radical of from 3 to 10 carbon atoms, an aralkyl radical of from 7 to 10 carbon atoms, and a phenyl radical, and may be identical to or different from each other, M represents polyvalent metals excepting for Group IA of the Periodic Table, n is zero, or an integer of 1 or 2.
The present invention further provides a heat sensitiv-e recording sheet which contains one or more than one of the compounds represented by the general ~ormula (I) as developer, and may further contain heat fusible materials which have a melting point of from 50 to 190C and is substantially colorless at room temperature. The heat sensitive recording sheet containing these heat fusible materials generally inc~eases more and more the rate of color development on heating, and lowers the temperature of color development.
Examples of the compounds represented by the general formula (I) include, but not to be limited thereto, zinc 2,2'-diphenolsulfide, nickel 2,2'-diphenolsulfone, zinc 2,2'-bis(p-cresol)sulfide, zinc 2,2'-bis(p-tert-butylphenol)sulfide, nickel 2,2'-bis(p-tert-butylphenol~sulfide, zinc 2,2'-bis(p-tert-butylphenol)sulfone, nickel 2,2'-bis~p-tert-butylphenol)sulfone, zinc 2,2'-bis(p-tert-amylphenol)sulfone, zinc 2,2'-bis~p-cyclohexyl)sulfide, zinc 2,2'-bis(p-cyclohexyl)sulfoxide, zinc 2,2'-bis(p-cyclohexyl)sulfone, nickel 2,2'-bis(p-cyclohexyl)sulfone,
3:
cobalt 2,2'-bis(p-cyclohexyl)sulfone, zinc 2,2'-bis(p-cumylphenol)sulfide, ¦ nickel 2,2'-bis(p-cumylphenol)sulfoxide, zinc 2,2'-bis(p-cumylphenol)sulfone, I magnesium 2,2'-bis(p-cumylphenol)sulfone, I nickel 2,2'-bis~p-cumylphenol)sulfone, ¦¦ manganese 2,2'-bis(p-cumylphenol)sulfone, zinc 2,2'-bis(p-pehnylphenol)sulfide, Il calcium 2,2'-bis(p-phenylphenol)sulfone, l nickel 2,2'-bis(p-phenylphenol)sulfone, cobalt 2,2'-bis(p-phenylphenol)sulfone, ! zinc 2,2~-bis(p-tert-octylphenol)sulfide, nickel 2,2'-bis(p-tert-octylphenol)sulfide, 'I cobalt 2,2'-bis(p-tert-octylpllenol)sulfide, zinc 2,2'-bis(p-octylphenol)sulfoxide, zinc 2,2'-bis(p-tert-octylphenol)sulfone, niclcel 2,2'-bis(p-tert-octylphenol)sulfone, magnesium 2,2'-bis~p-tert-octylphenol)sulfone, cobalt 2,2'-bis(p-tert-octylphenol)sulfone, calcium 2,2'-bis(p-tert-octylphenol)sulfone, i barium 2,2'-bis~p-tert-octylphenol)sulfone, zinc 2,2'-bis~p-dodecylphenol)sulfide, ~ nickel 2,2'-bis~p-dodecylphenol)sulfide, 111 cobalt 2,2'-bis~p-dodecylphenol)sulfide, ¦ zinc 2,2'-bis(p-dodecylphenol)sulfoxide, calcium 2,2'-bis(p-dodecylphenol)sulfoxide, nickel 2,2'-bis(p-dodecylphenol)sulfone, magnesium 2,2'-bis(p-dodecylphenol)sulfone, zinc 2,2'-bis(p-nonylphenol)sulfide, magnesium 2,2'-bis(p-nonylphenol)sulfide, !
calcium 2,2'-bis~p-nonylphenol)sulfoxide, zinc 2,2'-bis(p-nonylphenol)sulfone, chromium 2,2'-bis~p-nonylphenol)sulfone, nickel 2,2'-bis(p-nonylphenol)sulfone, cadmium 2,2'-bis~p-nonylphenol)sulfone, magnesium 2,2'-bis(p-nonylphenol)sulfone, and the like.
The developer represented by the general formula (I~
as mentioned above can be prepared by such a process as described below. For example, the developer is prepared by i0 reacting to be formed an alkali metal salt of .Qne member selected from bisphenol compounds consisting of 2,2'-bisphenolsulfide, 2,2'-bisphenolsulfoxide, and 2,2'-bisphenolsulfone compounds and a water soluble polyvalent metal salt in a solvent in which both salts are soluble.
That is, the developer is prepared by a process in which one gram equivalent of the bisphenol compound is reacted with 2 gram equivalents or more of hydroxides, alkoxides, or the like of alkali metal to form an alkali metal salt of bisphenol compounds, or an aqueous solution, alcohol solution or water-alcohol mixed solution thereof, and then one gram equivalent or more of the water soluble polyvalent metal salt is reacted therewith to form the developer.
Examples of the water soluble polyvalent metal salt used for the preparation of the developer employed in the present invention include chlorides, salts with inorganic acids such as sulfuric acid and nitric acid, salts with organic acids such as oxalic acid and acetic acid, and the like of polyvalent metals excepting Group IA of the Periodic Table such as magnesium, calcium, aluminium, zinc, tin, nickel, barium, ~ 96~3 strontium, cadm.ium, manganese, cobalt, chromium, and the li~e.
The he~t fusible material used in the present invention is a so'lid which is colorless at room temperature, or is almost colorless to such an extent that no feeling of color development is substantially given when impregnated in the heat sensitive recording sheet, and is such a material as to have a sharp melting point at a temperature suitable for recording on reproduction recording, that is, at a temperature in the neighbourhood o from 50 to 190C, and to dissolve either one or both of a coupler and a developer represented by the general formula (I) at a fused state thereof. Examples of the heat fusible material used include acetanilide, urea, diphenylamine, biphenyl,'naphthalene, ~-naphthol, ~-naphthol, bisphenol A, 4,4'-cyclohexilidenediphenol, phthalic anhydride, benzoic acicl, phthalic acid, methyl p-hydroxybenzoate, stearic acid, zinc stearate, ethyleneglycol ester stearate, triphenylphosphates, 2,2'-bisphenol sulfides, .2,2'-bisphenol-sulfoxides, or 2,2'-bisphenolsulfones.
A typical process ~or the preparation of the heat sensitive recording sheet of the present invention will be described ~elow. The coupler usable in the present invention include various materials which develop color by a fusi.on reaction thereof with a developer represented by the general formula (I). Examples of the coupler include electron donating and color assuming compounds such as 3~3'-bis(4^dimethylaminophenol)-6-dimethylaminophthalide(crystal violet lactone), 3-diethylamino-6-methyl-7-chlorofluoran, 3-diethylamino-7-chlorofluoran, 3-cyclohexy'lamino-6-chlorofluoran 7 3-diethylamino-7-dibenzylaminofluoran~
3-diethylamino-6-methyl-7-phenylaminofluoran, L~ - 7 -~ ~ 49613 1,3,3-trimethylindolino-6'-chloro-8'-methoxyspiropyran, ~ 3-methyl-2,2'-spiro bis(benzo [f] chromene), and the like.
Il A colorless or light colored coupler described as above, a developer represented by the general formula (I), or a mixutre of a coupler, developer, and a heat fusible material is thoroughly mixed with a solution prepared by dissolving a binder in water or an organic solvent, or with a dispersion of the binder therein to prepare a mixed solution.
; Examples of the binder used for the preparation of the mixed solution include synthetic polymers such as styrene butadiene polymer, polyvinylalcohol, carboxymethylcellulose, hydroxyethylcellulose, polystyrene, vinylchloride-vinylacetate copolymer, and acacia, and natural or modified natural polymers.
Examples of the solvent used include organic solvents such as ! benzene, toluene, acetone, methylene chloride, ethyl acetate, and cyclohexane, and water.
The mixed solution thus obtained is coated to be dried on a substrate such as paper, natural or synthetic resin film, and the like. The mixed solution may be allowed to flow into the substrate to be impregnated therein. The method of mixing and method of coating described as abvove are not limited to the heat sensitive recording sheet of the present invention. For example, the coupler and/or the heat fusible material are mixed with a binder solution, and separately the developer and/or the heat fusible material are mixed with a ~j binder solution. Then both mixtures thus obtained may be mixed together for coating on the substrate, or these two mixtures ¦ may be separately coated on the substrate to be coated thereon twice. Both mixtures may be coated on the same surface or surfaces separate from each other of the substrate, or may be ~ 6~ 3 coated on different substrates respectively.
The coating weight is generally above 0.5g/m2, preferably in the range of from l to lOg/m2 on dry weight basis.
A relative amount of each component of the heat sensitive recording sheet is wide variable, but suitably in the range of from l to 15 parts by weight of the coupler, 1 to 95 parts by weight of the developer represented by the general formula (I), 1 to 40 parts by weight of the binder, and zero or 0.5 to 200 parts by weight of the heat fusible material respectively on dry weight basis.
According to the heat sensitive recording sheet of the present invention, the coupler and developer are brought into contact with each other, while they are prepared, coated, and dried before being heated. Nevertheless, the heat sensitive recording sheet of the present invention have such advantages that no blushing oo~rs due to oolor de~elcpment, that stability ~eof with time is kept at a high level without lowering in color development performance by exposure thereof to light before : reproduction, that the color development is effected instantly on heating, and that the developed image has excellent light resistance and water resistance.
The present invention will be further explained by the following Exa~ples.
The method of measurement and assessment for various performances of the recording sheet are shown below.
1) Developed color density:
A recording sheet is subjected to heat color development under the following conditions, .~
.~' ~ . A
I
heating time 5 seconds pressure between heating , material and recording sheet lOg/cm2 on heating heating temperature range 60 to 180C
by use of Thermotest~ Rhodiaceta (manufactured by SETARAM Co.;
'¦ Type 7401).
I! Reflectance ~I) is measured in 10 minutes after color development by heating by use of an amber filter for TSS type Hunter color difference meter ~manufactured by Toyo Seiki Co.,Ltd.).
The lower the reflectance is, the higher the developed color density becomes.
ll ,~ 2) Fade resistance to light of developed image:
A sheet developed according to the procedure in 1) is lighted for a time period of from 30 minutes to 6 hours by use of a carbon arc lamp, and the following reflectanc,es are - measured by use of Hunter color difference meter in the same manner as in 1), ' Io: reflectance of sheet before color development, Is: reflectance of color developed sheet before lightening, In: reflectance of color developed sheet n hours after lightening.
The fade resistance to light of developed image is represented by use of the above reflectances as Degree of residue = In / Is ~ 100(%) Io-In / Io-Is A higher degree of residue is preferable.
.
, - 1 0 -~ 3) Storage stability:
jl A sheet before color development and a color developed ! sheet are stored 6 months at 25C, and the reflectance of the sheet before color development and that of the color developed sheet before storage are represented by Ko and Ko' respectively, I and those after storage are represented by K and K' respectively.
i~ The smaller the values of differences of K-Ko and K'-Ko' are, the more the storage stability are preferable.
¦ 4) water resistance:
A color developed recording sheet is kept in water for 2 hours, and a change in color density of a color developed image is observed with the naked eye.
~I ExamRle 1 Il Solution A: crystal violet lactone 7g il, 10 wt~ polyvinylalcohol 30g (Kurare # 217) ¦' water 13g Solution B: nickel 2,2'-bis(p-tert-octylphenol)sulfone 7g 10 wt~ polyvinylalcohol 30g water 13g ., ¦ Dispersions are prepared separately from solution A
and B respectively by use of a sand grinding mill, and two separate dispersions are mixed at such a ratio as 3 parts of solution A to 67 parts of solution B. The mixture is coated on fine paper and dried so that the coating weight may be in the range of from 2.5 to 3~5g/m2 on dry basis to obtain a heat sensitive recording sheet.
~496~3 Example 2 Il Solution A: crystal violet lactone 7g ¦~ 10 wt% polyvinylalcohol 30g water 13g , Solution B: nickel 2,2'-bis(p-tert-octylphenol)sulfone 7g zinc stearate 7g 10 wt% polyvinylalcohol 60g water 26g . Both solutions as above are subjected to the same procedure as in Exmaple 1 to prepare dispersions, and the dispersions thus obtained are mixed at such a ratio as 3 parts of solution A to 134 parts of solution B. The mixture is coated on a fine paper and dried so that the coating weight may be in the , range of from 2.5 to 3.5 g/m2 on dry basis to obtain a heat I sensitive recording sheet.
Example 3 Solution A: crystal violet lactone 7g 10 wt% polyvinylalcohol 30g water 13g Solution B: nickel 2,2'-bis~p-tert-octyl)sulfone 4.9g bisphenol A 2.lg 10 wt% polyvinylalcohol 30g water 13g Both solutions as above are subjected to the same procedure as in Example 1 to preapre dispersions, and thè
I dispersions thus obtained are mixed at such a ratio as 3 parts by I weight of solution A to 67 parts by weight of solution B. The resultant mixture is coated and dried so that the coating weight i 11~9613 may be in the range of from 2.5 to 3.5g/m2 on dry basis to obtain a heat sensitive recording sheet.
Comparative Example The prodecure of Example 1 is repeated except that bisphenol A is used instead of nickel 2,2'-bis~p-tert-octylphenol)-1l sulfone in Example 1 to obtain a heat sensitive recording sheet.
Examples 4 to 9 The procedrue of Example 1 is repeated by use ofnickel 2,2'-bis(p-tert-butylphenol)sulfide (Example 4), ,I zinc 2,2'-bis(p-tert-butylphenol)sulfoxide (Example 5), magnesium 2,2'-bis(p-tert-octylphenol)sulfone (Example 6), and cobalt 2,2'-bis(p-tert-octylphenol)sulfone (Example 7) respectively instead of nickel 2,2'-bis(p-tert-octylphenol)-sulfone in Example 1 to obtain a heat sensitive recording sheet.
Further, the procedure of Example 2 is repeated by use of calcium 2,2~-bis(p-tert-butylphenol)sulfone (Example 8), and nickel 2,2'-bis(p-cumylphenol)sulfone (Example 9) instead of nickel 2,2'-bis(p-tert-octylphenol)sulfone in Example 2 to obtain a heat sensitive recording sheet.
Results of performance assessment for heat sensitive recording sheets obtained in Examples 1 to 3 and Comparative Example are shown in Table 1, and results of performance assessment for heat sensitive recording sheets obtained in I Examples 4 to 9 are shown in Table 2.
Results of Examples 1 to 9 shows that every color developed image has excellent water resistance.
l - 13 -~9~i13 . _ ............. , _ ~ a~ a~ 0 ~ ~1 1` u~
. C~OOO~
. U~ ~ O~ ~ . ,.
M Lf) ~ O ~ E ` .4~
~ ~ R u ~o ~ ~f O o t~
o ~ 8 o 8 8~o ~ R r-l a~
_ D ~ ~ ~ O~ ~ ~ ~ o E~ ~~
~o~ ~
. _l ~ ~ ~o0 .
E~ , o ~ ~. . u o ~ c x u~
~- O O O O ~1 v o r ' U = _ O Ul X ~1 '1:: ~ _1 ~ ~1 O
o = ~8 u~ o o ~ " ~ ~=, c~x ,~
~d oo O O O ~ ~ ~0 ~ ~ E
o~ al ~ ~ ,n p~ a~ o~
a ~ oo J-~l ~ ~d~
? O O O ¦ O .~:: U o ~ ~ oo a~ ~D 1 . _ ,___ _ ~ .
~ ?
_I a) a) ~
_-_ ~ ~ .
. ~ 14 -- .~, -...`i~
Iu ~
C~ C~O
u~ E ~
~ a) ~ ~ E E E E E
S~ o al ~0 o ~3 g ~ s~ s~ s~
~ ~=~
o~ ~ s ~ CO ~ o o ~ ~o ~ ~ O ~
. ~ ~ ~
~rl ~ h ~ 0~ o ~1 111 1~ 0 ~ J ~ O ~ O U~
,D S~ S ~4 ~ ~ ~= .
q~ ~1 E ~ ,~ ~ c~ o o ~ o ~a ~J a~ o ~ ~ ~ .~ ~o ~ ~ co ~1 ~ ~ ~ ~ ~ o~
~ ~ ~ ~D O c~ 0 `D
E~ s o 4~ o~ o co U~J ~ _ o ~
. ~ C~o OO o o c~ O ~1 0 0 `J ~ oo U~ _l ~ ~ C`J
O
~ ~ oo s1~ ~
~s oO O 0 0 0 o __ . ... ~
~ . ~ U~
S ~ ~ ~ lY W ~ .
cobalt 2,2'-bis(p-cyclohexyl)sulfone, zinc 2,2'-bis(p-cumylphenol)sulfide, ¦ nickel 2,2'-bis(p-cumylphenol)sulfoxide, zinc 2,2'-bis(p-cumylphenol)sulfone, I magnesium 2,2'-bis(p-cumylphenol)sulfone, I nickel 2,2'-bis~p-cumylphenol)sulfone, ¦¦ manganese 2,2'-bis(p-cumylphenol)sulfone, zinc 2,2'-bis(p-pehnylphenol)sulfide, Il calcium 2,2'-bis(p-phenylphenol)sulfone, l nickel 2,2'-bis(p-phenylphenol)sulfone, cobalt 2,2'-bis(p-phenylphenol)sulfone, ! zinc 2,2~-bis(p-tert-octylphenol)sulfide, nickel 2,2'-bis(p-tert-octylphenol)sulfide, 'I cobalt 2,2'-bis(p-tert-octylpllenol)sulfide, zinc 2,2'-bis(p-octylphenol)sulfoxide, zinc 2,2'-bis(p-tert-octylphenol)sulfone, niclcel 2,2'-bis(p-tert-octylphenol)sulfone, magnesium 2,2'-bis~p-tert-octylphenol)sulfone, cobalt 2,2'-bis(p-tert-octylphenol)sulfone, calcium 2,2'-bis(p-tert-octylphenol)sulfone, i barium 2,2'-bis~p-tert-octylphenol)sulfone, zinc 2,2'-bis~p-dodecylphenol)sulfide, ~ nickel 2,2'-bis~p-dodecylphenol)sulfide, 111 cobalt 2,2'-bis~p-dodecylphenol)sulfide, ¦ zinc 2,2'-bis(p-dodecylphenol)sulfoxide, calcium 2,2'-bis(p-dodecylphenol)sulfoxide, nickel 2,2'-bis(p-dodecylphenol)sulfone, magnesium 2,2'-bis(p-dodecylphenol)sulfone, zinc 2,2'-bis(p-nonylphenol)sulfide, magnesium 2,2'-bis(p-nonylphenol)sulfide, !
calcium 2,2'-bis~p-nonylphenol)sulfoxide, zinc 2,2'-bis(p-nonylphenol)sulfone, chromium 2,2'-bis~p-nonylphenol)sulfone, nickel 2,2'-bis(p-nonylphenol)sulfone, cadmium 2,2'-bis~p-nonylphenol)sulfone, magnesium 2,2'-bis(p-nonylphenol)sulfone, and the like.
The developer represented by the general formula (I~
as mentioned above can be prepared by such a process as described below. For example, the developer is prepared by i0 reacting to be formed an alkali metal salt of .Qne member selected from bisphenol compounds consisting of 2,2'-bisphenolsulfide, 2,2'-bisphenolsulfoxide, and 2,2'-bisphenolsulfone compounds and a water soluble polyvalent metal salt in a solvent in which both salts are soluble.
That is, the developer is prepared by a process in which one gram equivalent of the bisphenol compound is reacted with 2 gram equivalents or more of hydroxides, alkoxides, or the like of alkali metal to form an alkali metal salt of bisphenol compounds, or an aqueous solution, alcohol solution or water-alcohol mixed solution thereof, and then one gram equivalent or more of the water soluble polyvalent metal salt is reacted therewith to form the developer.
Examples of the water soluble polyvalent metal salt used for the preparation of the developer employed in the present invention include chlorides, salts with inorganic acids such as sulfuric acid and nitric acid, salts with organic acids such as oxalic acid and acetic acid, and the like of polyvalent metals excepting Group IA of the Periodic Table such as magnesium, calcium, aluminium, zinc, tin, nickel, barium, ~ 96~3 strontium, cadm.ium, manganese, cobalt, chromium, and the li~e.
The he~t fusible material used in the present invention is a so'lid which is colorless at room temperature, or is almost colorless to such an extent that no feeling of color development is substantially given when impregnated in the heat sensitive recording sheet, and is such a material as to have a sharp melting point at a temperature suitable for recording on reproduction recording, that is, at a temperature in the neighbourhood o from 50 to 190C, and to dissolve either one or both of a coupler and a developer represented by the general formula (I) at a fused state thereof. Examples of the heat fusible material used include acetanilide, urea, diphenylamine, biphenyl,'naphthalene, ~-naphthol, ~-naphthol, bisphenol A, 4,4'-cyclohexilidenediphenol, phthalic anhydride, benzoic acicl, phthalic acid, methyl p-hydroxybenzoate, stearic acid, zinc stearate, ethyleneglycol ester stearate, triphenylphosphates, 2,2'-bisphenol sulfides, .2,2'-bisphenol-sulfoxides, or 2,2'-bisphenolsulfones.
A typical process ~or the preparation of the heat sensitive recording sheet of the present invention will be described ~elow. The coupler usable in the present invention include various materials which develop color by a fusi.on reaction thereof with a developer represented by the general formula (I). Examples of the coupler include electron donating and color assuming compounds such as 3~3'-bis(4^dimethylaminophenol)-6-dimethylaminophthalide(crystal violet lactone), 3-diethylamino-6-methyl-7-chlorofluoran, 3-diethylamino-7-chlorofluoran, 3-cyclohexy'lamino-6-chlorofluoran 7 3-diethylamino-7-dibenzylaminofluoran~
3-diethylamino-6-methyl-7-phenylaminofluoran, L~ - 7 -~ ~ 49613 1,3,3-trimethylindolino-6'-chloro-8'-methoxyspiropyran, ~ 3-methyl-2,2'-spiro bis(benzo [f] chromene), and the like.
Il A colorless or light colored coupler described as above, a developer represented by the general formula (I), or a mixutre of a coupler, developer, and a heat fusible material is thoroughly mixed with a solution prepared by dissolving a binder in water or an organic solvent, or with a dispersion of the binder therein to prepare a mixed solution.
; Examples of the binder used for the preparation of the mixed solution include synthetic polymers such as styrene butadiene polymer, polyvinylalcohol, carboxymethylcellulose, hydroxyethylcellulose, polystyrene, vinylchloride-vinylacetate copolymer, and acacia, and natural or modified natural polymers.
Examples of the solvent used include organic solvents such as ! benzene, toluene, acetone, methylene chloride, ethyl acetate, and cyclohexane, and water.
The mixed solution thus obtained is coated to be dried on a substrate such as paper, natural or synthetic resin film, and the like. The mixed solution may be allowed to flow into the substrate to be impregnated therein. The method of mixing and method of coating described as abvove are not limited to the heat sensitive recording sheet of the present invention. For example, the coupler and/or the heat fusible material are mixed with a binder solution, and separately the developer and/or the heat fusible material are mixed with a ~j binder solution. Then both mixtures thus obtained may be mixed together for coating on the substrate, or these two mixtures ¦ may be separately coated on the substrate to be coated thereon twice. Both mixtures may be coated on the same surface or surfaces separate from each other of the substrate, or may be ~ 6~ 3 coated on different substrates respectively.
The coating weight is generally above 0.5g/m2, preferably in the range of from l to lOg/m2 on dry weight basis.
A relative amount of each component of the heat sensitive recording sheet is wide variable, but suitably in the range of from l to 15 parts by weight of the coupler, 1 to 95 parts by weight of the developer represented by the general formula (I), 1 to 40 parts by weight of the binder, and zero or 0.5 to 200 parts by weight of the heat fusible material respectively on dry weight basis.
According to the heat sensitive recording sheet of the present invention, the coupler and developer are brought into contact with each other, while they are prepared, coated, and dried before being heated. Nevertheless, the heat sensitive recording sheet of the present invention have such advantages that no blushing oo~rs due to oolor de~elcpment, that stability ~eof with time is kept at a high level without lowering in color development performance by exposure thereof to light before : reproduction, that the color development is effected instantly on heating, and that the developed image has excellent light resistance and water resistance.
The present invention will be further explained by the following Exa~ples.
The method of measurement and assessment for various performances of the recording sheet are shown below.
1) Developed color density:
A recording sheet is subjected to heat color development under the following conditions, .~
.~' ~ . A
I
heating time 5 seconds pressure between heating , material and recording sheet lOg/cm2 on heating heating temperature range 60 to 180C
by use of Thermotest~ Rhodiaceta (manufactured by SETARAM Co.;
'¦ Type 7401).
I! Reflectance ~I) is measured in 10 minutes after color development by heating by use of an amber filter for TSS type Hunter color difference meter ~manufactured by Toyo Seiki Co.,Ltd.).
The lower the reflectance is, the higher the developed color density becomes.
ll ,~ 2) Fade resistance to light of developed image:
A sheet developed according to the procedure in 1) is lighted for a time period of from 30 minutes to 6 hours by use of a carbon arc lamp, and the following reflectanc,es are - measured by use of Hunter color difference meter in the same manner as in 1), ' Io: reflectance of sheet before color development, Is: reflectance of color developed sheet before lightening, In: reflectance of color developed sheet n hours after lightening.
The fade resistance to light of developed image is represented by use of the above reflectances as Degree of residue = In / Is ~ 100(%) Io-In / Io-Is A higher degree of residue is preferable.
.
, - 1 0 -~ 3) Storage stability:
jl A sheet before color development and a color developed ! sheet are stored 6 months at 25C, and the reflectance of the sheet before color development and that of the color developed sheet before storage are represented by Ko and Ko' respectively, I and those after storage are represented by K and K' respectively.
i~ The smaller the values of differences of K-Ko and K'-Ko' are, the more the storage stability are preferable.
¦ 4) water resistance:
A color developed recording sheet is kept in water for 2 hours, and a change in color density of a color developed image is observed with the naked eye.
~I ExamRle 1 Il Solution A: crystal violet lactone 7g il, 10 wt~ polyvinylalcohol 30g (Kurare # 217) ¦' water 13g Solution B: nickel 2,2'-bis(p-tert-octylphenol)sulfone 7g 10 wt~ polyvinylalcohol 30g water 13g ., ¦ Dispersions are prepared separately from solution A
and B respectively by use of a sand grinding mill, and two separate dispersions are mixed at such a ratio as 3 parts of solution A to 67 parts of solution B. The mixture is coated on fine paper and dried so that the coating weight may be in the range of from 2.5 to 3~5g/m2 on dry basis to obtain a heat sensitive recording sheet.
~496~3 Example 2 Il Solution A: crystal violet lactone 7g ¦~ 10 wt% polyvinylalcohol 30g water 13g , Solution B: nickel 2,2'-bis(p-tert-octylphenol)sulfone 7g zinc stearate 7g 10 wt% polyvinylalcohol 60g water 26g . Both solutions as above are subjected to the same procedure as in Exmaple 1 to prepare dispersions, and the dispersions thus obtained are mixed at such a ratio as 3 parts of solution A to 134 parts of solution B. The mixture is coated on a fine paper and dried so that the coating weight may be in the , range of from 2.5 to 3.5 g/m2 on dry basis to obtain a heat I sensitive recording sheet.
Example 3 Solution A: crystal violet lactone 7g 10 wt% polyvinylalcohol 30g water 13g Solution B: nickel 2,2'-bis~p-tert-octyl)sulfone 4.9g bisphenol A 2.lg 10 wt% polyvinylalcohol 30g water 13g Both solutions as above are subjected to the same procedure as in Example 1 to preapre dispersions, and thè
I dispersions thus obtained are mixed at such a ratio as 3 parts by I weight of solution A to 67 parts by weight of solution B. The resultant mixture is coated and dried so that the coating weight i 11~9613 may be in the range of from 2.5 to 3.5g/m2 on dry basis to obtain a heat sensitive recording sheet.
Comparative Example The prodecure of Example 1 is repeated except that bisphenol A is used instead of nickel 2,2'-bis~p-tert-octylphenol)-1l sulfone in Example 1 to obtain a heat sensitive recording sheet.
Examples 4 to 9 The procedrue of Example 1 is repeated by use ofnickel 2,2'-bis(p-tert-butylphenol)sulfide (Example 4), ,I zinc 2,2'-bis(p-tert-butylphenol)sulfoxide (Example 5), magnesium 2,2'-bis(p-tert-octylphenol)sulfone (Example 6), and cobalt 2,2'-bis(p-tert-octylphenol)sulfone (Example 7) respectively instead of nickel 2,2'-bis(p-tert-octylphenol)-sulfone in Example 1 to obtain a heat sensitive recording sheet.
Further, the procedure of Example 2 is repeated by use of calcium 2,2~-bis(p-tert-butylphenol)sulfone (Example 8), and nickel 2,2'-bis(p-cumylphenol)sulfone (Example 9) instead of nickel 2,2'-bis(p-tert-octylphenol)sulfone in Example 2 to obtain a heat sensitive recording sheet.
Results of performance assessment for heat sensitive recording sheets obtained in Examples 1 to 3 and Comparative Example are shown in Table 1, and results of performance assessment for heat sensitive recording sheets obtained in I Examples 4 to 9 are shown in Table 2.
Results of Examples 1 to 9 shows that every color developed image has excellent water resistance.
l - 13 -~9~i13 . _ ............. , _ ~ a~ a~ 0 ~ ~1 1` u~
. C~OOO~
. U~ ~ O~ ~ . ,.
M Lf) ~ O ~ E ` .4~
~ ~ R u ~o ~ ~f O o t~
o ~ 8 o 8 8~o ~ R r-l a~
_ D ~ ~ ~ O~ ~ ~ ~ o E~ ~~
~o~ ~
. _l ~ ~ ~o0 .
E~ , o ~ ~. . u o ~ c x u~
~- O O O O ~1 v o r ' U = _ O Ul X ~1 '1:: ~ _1 ~ ~1 O
o = ~8 u~ o o ~ " ~ ~=, c~x ,~
~d oo O O O ~ ~ ~0 ~ ~ E
o~ al ~ ~ ,n p~ a~ o~
a ~ oo J-~l ~ ~d~
? O O O ¦ O .~:: U o ~ ~ oo a~ ~D 1 . _ ,___ _ ~ .
~ ?
_I a) a) ~
_-_ ~ ~ .
. ~ 14 -- .~, -...`i~
Iu ~
C~ C~O
u~ E ~
~ a) ~ ~ E E E E E
S~ o al ~0 o ~3 g ~ s~ s~ s~
~ ~=~
o~ ~ s ~ CO ~ o o ~ ~o ~ ~ O ~
. ~ ~ ~
~rl ~ h ~ 0~ o ~1 111 1~ 0 ~ J ~ O ~ O U~
,D S~ S ~4 ~ ~ ~= .
q~ ~1 E ~ ,~ ~ c~ o o ~ o ~a ~J a~ o ~ ~ ~ .~ ~o ~ ~ co ~1 ~ ~ ~ ~ ~ o~
~ ~ ~ ~D O c~ 0 `D
E~ s o 4~ o~ o co U~J ~ _ o ~
. ~ C~o OO o o c~ O ~1 0 0 `J ~ oo U~ _l ~ ~ C`J
O
~ ~ oo s1~ ~
~s oO O 0 0 0 o __ . ... ~
~ . ~ U~
S ~ ~ ~ lY W ~ .
Claims (6)
1. A heat sensitive recording sheet prepared by coating on a sheet substrate, or by impregnating therein a coupler, developer, and binder, characterized in that said developer is one or more than one of the compounds represented by the general formula (I) (I) where R Represents hydrogen, an alkyl radical of from 1 to 12 carbon atoms, a cycloalkyl radical of from 3 to 10 carbon atoms, an aralkyl radical of from 7 to 10 carbon atoms, and a phenyl radical, and may be identical to or different from each other, M represents polyvalent metals excepting for Group IA of the Periodic Table, n is zero, or an integer of 1 or 2.
2. A heat sensitive recording sheet claimed in claim 1, wherein M in the general formula (I) is magnesium, calcium, aluminium, zinc, tin, nickel, cobalt, barium, strontium, cadmium, manganese, or chromium.
3. A heat sensitive recording sheet claimed in claim 2, wherein M in the general formula (I) is nickel, zinc, cobalt, or calcium.
4. A heat sensitive recording sheet claimed in claim 1, wherein R in the general formula (I) is tert'-butyl, amyl, tert-octyl, nonyl, dodecyl, or cumyl radical.
5. A heat sensitive recording sheet prepared by coating on a sheet substrate, or by impregnating therein a coupler, developer, and binder, characterized in that said developer is one or more than one of the compounds represented by the general formula (I) (I) where R represents hydrogen, an alkyl radical of from 1 to 12 carbon atoms, a cycloalkyl radical of from 3 to 10 carbon atoms, an aralkyl radical of from 7 to 10 carbon atoms, and a phenyl radical, and may be identical to or different from each other, M represents polyvalent metals excepting for Group IA of the Periodic Table, n is zero, or an integer of 1 or 2, and said sheet further contains heat fusible materials which have a melting point of from 50° to 190°C and is substantially colorless at room temperature.
6. A heat sensitive recording sheet as claimed in claim 5 wherein said heat fusible material is acetanilide, urea, diphenylamine, biphenyl, naphthalene, .alpha.-naphthol, .beta.-naphthol, bisphenol A, 4,4'-cyclohexilidenediphenol, phthalic anhydride, benzoic acid, phthalic acid, methyl p-hydroxybenzoate, stearic acid, zinc stearate, ethyleneglycol ester stearate, triphenylphosphates, 2,2'-bisphenol sulfides, 2,2'-bisphenolsulfoxides, or 2,2'-bisphenolsulfones.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP75623/1979 | 1979-06-18 | ||
| JP54075623A JPS6025277B2 (en) | 1979-06-18 | 1979-06-18 | heat sensitive recording sheet |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1149613A true CA1149613A (en) | 1983-07-12 |
Family
ID=13581520
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000354135A Expired CA1149613A (en) | 1979-06-18 | 1980-06-17 | Heat sensitive recording sheet |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US4407892A (en) |
| EP (2) | EP0025820B1 (en) |
| JP (1) | JPS6025277B2 (en) |
| CA (1) | CA1149613A (en) |
| DE (1) | DE3071443D1 (en) |
| WO (1) | WO1980002820A1 (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CH655906A5 (en) * | 1981-06-15 | 1986-05-30 | Ciba Geigy Ag | PRESSURE SENSITIVE OR HEAT SENSITIVE RECORDING MATERIAL. |
| US4614757A (en) * | 1984-03-19 | 1986-09-30 | The Standard Register Company | Color developer for pressure-sensitive recording papers |
| US4556687A (en) * | 1984-03-19 | 1985-12-03 | The Standard Register Company | Color developer for pressure-sensitive recording papers |
| JPS63251282A (en) * | 1987-04-08 | 1988-10-18 | Fuji Photo Film Co Ltd | Color developer sheet |
| JPH0529783Y2 (en) * | 1987-12-12 | 1993-07-29 | ||
| DE19844390B4 (en) | 1998-09-28 | 2005-09-22 | Wilhelm Fette Gmbh | Process for producing tablets in a rotary tablet machine |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3244550A (en) * | 1961-08-31 | 1966-04-05 | Burroughs Corp | Manifold sheets coated with lactone and related chromogenous compounds and reactive phenolics and method of marking |
| US3244549A (en) * | 1961-08-31 | 1966-04-05 | Burroughs Corp | Manifold sheets coated with lactone and related chromogenous compounds and reactive phenolics and method of marking |
| US3336337A (en) * | 1961-08-31 | 1967-08-15 | Burroughs Corp | Chromogenous tetrakis(aminophenyl) derivatives of benzodifuran |
| US3560229A (en) * | 1961-08-31 | 1971-02-02 | Burroughs Corp | Colorforming compositions and methods for preparing and controlling same |
| JPS521329B1 (en) * | 1970-12-26 | 1977-01-13 | ||
| DE2342758A1 (en) * | 1973-08-24 | 1975-04-10 | Pelikan Werke Wagner Guenther | Colour reaction system with metal carboxylate or sulphonate - as developer using org ether cpd as solvent for colour former |
| JPS5348751A (en) * | 1976-10-16 | 1978-05-02 | Kanzaki Paper Mfg Co Ltd | Heat sensitive recording member |
| JPS5386229A (en) * | 1977-01-07 | 1978-07-29 | Kanzaki Paper Mfg Co Ltd | Thermosensitive recording body |
| JPS6014717B2 (en) * | 1978-02-08 | 1985-04-15 | 三井東圧化学株式会社 | Color developer sheet for pressure-sensitive copying paper |
| JPS5953193B2 (en) * | 1978-02-15 | 1984-12-24 | 神崎製紙株式会社 | heat sensitive recording material |
| GB2032484B (en) * | 1978-10-11 | 1983-01-19 | Mitsui Toatsu Chemicals | Colour-developing sheet for pressure-sensitive recording sheets |
| US4260179A (en) * | 1979-08-22 | 1981-04-07 | Mitsui Toatsu Chemicals Inc. | Color-developing sheet for pressure-sensitive recording sheets |
-
1979
- 1979-06-18 JP JP54075623A patent/JPS6025277B2/en not_active Expired
-
1980
- 1980-06-17 DE DE8080901121T patent/DE3071443D1/en not_active Expired
- 1980-06-17 WO PCT/JP1980/000135 patent/WO1980002820A1/en active IP Right Grant
- 1980-06-17 CA CA000354135A patent/CA1149613A/en not_active Expired
- 1980-06-18 EP EP19800103392 patent/EP0025820B1/en not_active Expired
- 1980-12-30 EP EP19800901121 patent/EP0030563B1/en not_active Expired
-
1982
- 1982-07-20 US US06/400,016 patent/US4407892A/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| EP0030563B1 (en) | 1986-02-26 |
| US4407892A (en) | 1983-10-04 |
| JPS56191A (en) | 1981-01-06 |
| EP0025820A1 (en) | 1981-04-01 |
| JPS6025277B2 (en) | 1985-06-17 |
| EP0030563A1 (en) | 1981-06-24 |
| WO1980002820A1 (en) | 1980-12-24 |
| DE3071443D1 (en) | 1986-04-03 |
| EP0030563A4 (en) | 1981-08-31 |
| EP0025820B1 (en) | 1986-02-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1120183A (en) | Method of preparing zinc-modified phenol-aldehyde novolak resins | |
| US4165103A (en) | Method of preparing zinc-modified phenol-aldehyde novolak resins and use as a color-developing agent | |
| CA1139941A (en) | Thermally-responsive record material | |
| CA1175226A (en) | Heat-sensitive recording materials | |
| CA2111484C (en) | Recording sheet | |
| US4312522A (en) | Heat sensitive recording sheet | |
| FI71694B (en) | TRYCKKAENSLIGT ELLER VAERMEKAENSLIGT UPPTECKNINGSMATERIAL | |
| CA1149613A (en) | Heat sensitive recording sheet | |
| CA1264549A (en) | Heat-sensitive recording material | |
| US4839332A (en) | Heat-sensitive recording material | |
| US4431706A (en) | Heat sensitive recording sheet | |
| US4283458A (en) | Heat-sensitive recording paper containing a novel electron accepting compound | |
| EP0058083B1 (en) | Heat-sensitive color-forming recording material and its preparation | |
| GB2071860A (en) | Heat sensitive materials | |
| US4729984A (en) | Heat sensitive recording sheets containing sulfone derivatives | |
| US4489336A (en) | Pressure sensitive manifold paper | |
| US4523205A (en) | Heat-sensitive recording materials | |
| US4612557A (en) | Hydroxydiphenyl sulfone derivative and heat-sensitive recording material using the derivative | |
| JPS6334838B2 (en) | ||
| GB2198855A (en) | Heat-sensitive recording material | |
| CA1312730C (en) | Thermal recording material | |
| KR830002217B1 (en) | Thermal recording sheet | |
| US4586061A (en) | Thermally-responsive record material | |
| JPS58205795A (en) | Heat-sensitive recording material | |
| JPS606795B2 (en) | pressure sensitive recording sheet |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |