EP0688680B1 - Elément transparent pour enregistrement thermique - Google Patents

Elément transparent pour enregistrement thermique Download PDF

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Publication number
EP0688680B1
EP0688680B1 EP95108850A EP95108850A EP0688680B1 EP 0688680 B1 EP0688680 B1 EP 0688680B1 EP 95108850 A EP95108850 A EP 95108850A EP 95108850 A EP95108850 A EP 95108850A EP 0688680 B1 EP0688680 B1 EP 0688680B1
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EP
European Patent Office
Prior art keywords
thermal recording
group
recording medium
recording layer
transparent
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EP95108850A
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German (de)
English (en)
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EP0688680B2 (fr
EP0688680A1 (fr
Inventor
Hiroshi Goto
Hideaki Ema
Kiyoshi Sakai
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Ricoh Co Ltd
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Ricoh Co Ltd
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Priority claimed from JP33185594A external-priority patent/JPH08118811A/ja
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Priority to EP98115352A priority Critical patent/EP0890448A1/fr
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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
    • B41M5/40—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used characterised by the base backcoat, intermediate, or covering layers, e.g. for thermal transfer dye-donor or dye-receiver sheets; Heat, radiation filtering or absorbing means or layers; combined with other image registration layers or compositions; Special originals for reproduction by thermography
    • B41M5/42—Intermediate, backcoat, or covering layers
    • 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
    • B41M5/323—Organic colour formers, e.g. leuco dyes
    • B41M5/327—Organic colour formers, e.g. leuco dyes with a lactone or lactam ring
    • 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
    • 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
    • B41M5/3372—Macromolecular compounds

Definitions

  • the present invention relates to a thermal recording medium based on a coloration reaction of an electron-donating chromophoric compound with an electron-accepting compound and, in particular, a transparent thermal recording medium which is useful for a sheet of a block copy film (for image forming) for plate-making in gravure printing, offset lithography and screen process printing, more particularly, screen process printing for dyeing, an image-forming film sheet for an overhead projector (hereinafter referred to as an "OHP"), an image forming film for a CAD system and a geologic map.
  • OHP overhead projector
  • thermal recording medium which is based on the coloration reaction of the electron-donating chromophoric compound (hereinafter also referred to as a "color-producing agent"), is well known in the art.
  • thermal recording medium has been required to be expanded for various purposes such as the OHP, a sub origin in the diazo process and designing of drawings. Furthermore, the thermal recording medium has been required to be used for the block copy film for gravure printing, offset lithography and screen printing.
  • the known thermal recording medium for the block copy film does not yet achieve the above-mentioned requirements.
  • Transparent thermal recording media are described in Japanese Patent Application No.61-121875 and JP-A-1-99873, in which an image can be recorded directly on the transparent thermal recording medium with a thermal head.
  • the color-producing agent must be enclosed in a microcapsule, and application liquid, which comprises an emulsified dispersion material formed by emulsifying and dispersing a developer dissolved in an organic solvent which is slightly soluble or insoluble in water, must be applied on a transparent support.
  • the thermal recording medium formed in the above-mentioned way has an insufficient transparency.
  • transparent thermal recording media of good transparency have the disadvantage that the stability of a coloring-image formed by the thermal energy is low.
  • the transparent thermal recording media, used for the block copy film for plate-making have a low contrast between a color-imaging portion and a non-imaging portion at a wavelength range from 370 nm to 450 nm, so that the transparent thermal recording media cannot be used for the block copy film for photosensitive plate-making when the block copy film utilizes a lamp having a wavelength range from 370 nm to 450 nm.
  • the conventional transparent thermal recording medium has another problem that an offset between images printed on the respective films can hardly be found during an inspection of the block copy film formed, for example, by an automatic tracer, since the conventional transparent thermal recording medium has a substantially black coloring tone when more than two block copy films are superimposed together on the inspection.
  • the color-imaging portion of the block copy film has a high absorption of light at wavelengths ranging from 450 nm to 600 nm, which is particularly visible by visual inspection, and is deemed to be black, and thus results in a difficulty in determining whether the imaging portions of the superimposed block copy films are registered together.
  • a transparent thermal recording medium comprises: a thermal recording layer, which is provided on a transparent layer and comprises an electron-donating chromophoric compound, an electron-accepting compound and binder resin; and a further-provided protective layer having an approximately equal refractive index with respect to the refractive index of said thermal recording layer, wherein said binder resin is a compound having a hydroxyl group and/or a carboxyl group.
  • a transparent thermal recording medium is further provided, wherein the refractive index of said binder resin and the refractive index of resin forming said protective layer range from 1.45 to 1.60 at ordinary temperature.
  • a transparent thermal recording medium as defined above is also provided, wherein said electron-accepting compound is an organo phosphoric acid compound.
  • a transparent thermal recording medium as defined above is provided, wherein said organo phosphoric acid compound is selected from phosphonic acid compounds of the following general formulas (I) and (II): where R is selected from linear alkyl groups having from 16 to 24 carbon atoms; and where R' is selected from linear alkyl groups having from 13 to 23 carbon atoms.
  • a transparent thermal recording medium as defined above is provided, wherein said electron-donating chromophoric compound is selected from fluoran compounds of the following general formulas (III), (IV), (V), (VI), (VII) and (VIII): where R 1 is selected from alkyl groups having equal to or less than 8 carbon atoms, R 2 is selected from a hydrogen atom and an alkyl group having equal to or less than 4 carbon atoms, and X represents a halogen atom selected from a fluorine atom, a chlorine atom and a bromine atom; where R 3 is selected from a hydrogen atom and an alkyl group having equal to or less than 8 carbon atoms, and R 4 is selected from alkyl groups having equal to or less than 8 carbon atoms; where R 5 and R 6 are selected from alkyl groups having equal to or less than 8 carbon atoms, and R 7 is selected from a hydrogen atom, a lower alkyl group and a lower alkoxy group
  • a transparent thermal recording medium comprises: a thermal recording layer provided on a transparent support, wherein said thermal recording layer consists essentially of an electron-donating chromophoric compound, an organo phosphoric acid compound, and binder resin having a refractive index ranging from 1.45 to 1.60 at ordinary temperature and including a hydroxyl group and/or a carboxyl group; and a protective layer provided on said thermal recording layer, said protective layer consisting essentially of resin having a refractive index ranging from 1.45 to 1.60 at ordinary temperature.
  • a transparent thermal recording medium comprises: a thermal recording layer provided on a transparent support, wherein said thermal recording layer consists essentially of an electron-donating chromophoric compound, an organo phosphoric acid compound, and binder resin having a refractive index ranging from 1.45 to 1.60 at ordinary temperature and including a hydroxyl group and/or a carboxyl group; and a protective layer provided on said thermal recording layer, said protective layer consisting essentially of resin having a refractive index ranging from 1.45 to 1.60 at ordinary temperature, wherein the difference in light transmission factors between a color-producing imaging portion formed on the transparent thermal recording medium by a thermal energy and a non-imaging portion is over 35% at a wavelength ranging from 380 nm to 440 nm or ranging from 350 nm to 470 nm, respectively.
  • the difference of the light transmission factor (A%) is determined by the light transmission factor in a non-imaging portion (B%) and the light transmission factor in an imaging portion (C%) according to the following equation.
  • A B-C
  • An electron-donating chromophoric compound as used in the present invention is per se an achromatic or pale dye precursor, and a fluoran compound is a non-limiting example of typically known electron-donating chromophoric compounds.
  • the fluoran compound can be selected from the following compounds:
  • a color-producing agent according to the present invention is preferably selected from fluoran compounds of the general formulas (III), (IV), (V), (VI), (VII) and (VIII). Said color-producing agents can be selected from the following compounds.
  • a developer for coloring the above-described color-producing agent is preferably selected from a phenol compound and an organo phosphoric acid compound.
  • the phenol compound may be selected from a gallic acid compound, a protocatechuic acid compound and bis(hydroxyphenyl)acetic acid.
  • the organo phosphoric acid compound may be selected from an alkylphosphonic acid compound and an ⁇ -hydroxyalkylphosphonate. The organo phosphoric acid is excellent in surface blushing and thermal sensitivity.
  • the organo phosphoric acid is preferably selected from a phosphonate of the general formulas (I) and (II): where R is selected from linear alkyl groups having from 16 to 24 carbon atoms; and where R' is selected from linear alkyl groups having from 13 to 23 carbon atoms.
  • the phosphonic acid compound of general formula (I) may be selected from hexadecylphosphonate, octadecylphosphonate, eicosylphosphonate, docosylphosphonate and tetracosylphosphonate.
  • the phosphonic acid compound of general formula (II) may be selected from ⁇ -hydroxytetradecylphosphonate, ⁇ -hydroxyhexadecylphosphonate, ⁇ -hydroxyoctadecylphosphonate, ⁇ -hydroxyeicosylphosphonate and ⁇ -hydroxytetracosylphosphonate.
  • either one developer solely or a mixture of two or more developers can be employed.
  • Either of one color-producing agent or a mixture of two or more color-producing agents can also be employed.
  • the average particle size of the developer used according to the present invention is preferably equal to or less than 10 ⁇ m, and more preferably, the average particle size is equal to or less than 1 ⁇ m and the maximum particle size of the developer is not more than 1 ⁇ m, so that the thermal sensitivity and the resolution of the thermal recording medium can be improved.
  • the binder resin is selected from compounds including a hydroxyl group and/or a carboxylic acid group to satisfy the above-mentioned requirements, and preferably the compound has a refractive index (hereinafter also referred to as R.I.) ranging from 1.45 to 1.60 at ordinary temperature.
  • oxides as impurities included in the binder resin, and the ultraviolet absorbing agent and antioxidant agent having a hydroxyl group or a carboxyl group in the molecule can perform the same function as the above binder resin.
  • an improvement of the light stability of the thermal recording medium according to the present invention can be achieved by including a light stabilizer in either the thermal recording layer or the protective layer.
  • the light stabilizer may be selected from an ultraviolet absorber, an antioxidant, an anti-aging agent, an extinctive agent of a singlet enzyme and an extinctive agent of a superoxide anion.
  • the ultraviolet absorber may be selected from a benzophenone ultraviolet absorber such as 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 4-dodecyloxy-2-hydroxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2',1,4'-tetrahydroxybenzophenone, 2-hydroxy-4-methoxy-2'-carboxybenzophenone, 2-hydroxy-4-oxybenzylbenzophenone, 2-hydroxy-4-chlorobenzophenone, 2-hydroxy-5-chlorobenzophenone, 2-hydroxy-4-methoxy-4'-methylbenzophenone, 2-hydroxy-4-n-heptoxybenzophenone, 2-hydroxy-3,6-dichloro-4-methoxybenzophenone, 2-hydroxy-3,6-dichloro-4-ethoxybenzophen
  • the antioxidant and the anti-aging agent may be selected, for example, from 2,6-ditertiary-butyl-4-methylphenol, 2,4,6-tritertiarybutylphenol, styrene-modified phenol, 2,2'-methylenebis(4-methyl-6-tertiarybutylphenol), 4,4'-isopropylidenebisphenol, 2,6-bis(2'-hydroxy-3'-tertiarybutyl-5'-methylbenzyl)-4-methylphenol, 4,4'-thiobis-(3-methyl-6-tertiarybutylphenol), tetrakis- ⁇ methylene(3,5-ditertiarybutyl-4-hydroxyhydrocinnamate) ⁇ methane, para-hydroxyphenyl-3-naphthylamine, 2,2,4-trimethyl-1,2-dihydroquinoline, thiobis( ⁇ -naphthol), mercaptobenzothiazole, mercaptobenzimidazole
  • the extinctive agent of the singlet enzyme may be selected from a carotene class, a pigment class, an amine class, a phenol class, a nickel complex group and a sulfide class.
  • the extinctive agent of the singlet enzyme may be, for example, selected from 1,4-diazabicyclo(2.2.2)octane, ⁇ -carotene, 1,3-cyclohexadiene, 2-diethylaminomethylfuran, 2-phenylaminomethylfuran, 9-diethylaminomethylanthracene, 5-diethylaminomethyl-6-phenyl-3,4-dihydroxypyran, nickeldimethyldithiocarbamate, nickeldibutyldithiocarbamate, nickel-3,5-di-t-butyl-4-hydroxybenzyl-O-ethylphosphonate, nickel-3,5-di-t-butyl-4-hydroxybenzyl-O-butylphosphonate, nickel ⁇ 2,2'-thiobis(4-t-octylphenolate) ⁇ (n-butylamine), nickel- ⁇ 2,2'-thiobis(4-t-octylphenolate
  • extinctive agent of the superoxide anion according to the present invention may be selected from superoxide dismutase, a cobalt[III] complex and a nickel[II] complex. These are used solely or in a mixture of two or more thereof.
  • a substrate of the thermal recording medium according to the present invention is a transparent support, which preferably has a refractive index ranging from 1.45 to 1.60 at ordinary temperature.
  • the transparent support can be generally selected from a polyester film such as poly(ethylene terephthalate) and poly(butylene terephthalate); a cellulose derivative film such as cellulose triacetate; a polyolefin film such as polypropylene and polyethylene; a polystyrene film; and a laminate thereof.
  • the adhesive layer may be generally formed of acryl resin, saturated polyester resin and hardened resin thereof.
  • the thermal recording layer contains fine particles of the developer dispersed in the binder resin, so that the surface and the inside of the thermal recording layer are inhomogeneous. Since this inhomogeneity results in the presence of air in an unevenness or vacancy of the thermal recording layer and a difference of the refractive index in the thermal recording layer, light thus being scattered, the thermal recording layer appears to be opaque or semitransparent.
  • the unevenness and the vacancy of the thermal recording layer is removed by applying and drying (hardening) some resin on the opaque or semitransparent recording layer, in which the resin has the same refractive index at ordinary temperature as that of the binder resin of the thermal recording layer, and thus the thermal recording layer remains homogeneous.
  • the resulting protective layer not only contributes to transparency of the medium, but also effectively improves chemical resistance, water resistance, abrasion resistance, light fastness and a head matching property. Therefore, the protective layer is an essential component of the high performance transparent thermal recording medium.
  • the protective layer according to the present invention includes a coating formed principally of water-soluble resin or hydrophobic resin as well as a coating formed principally of ultraviolet curable resin or electron beam curable resin. Due to the formation of such a protective layer, a thermal recording medium with no practical problems can be achieved even if an organic solvent, a plasticiser, oil, sweat and water contact the thermal recording medium. Furthermore, an inclusion of an organic or inorganic filler and a slip agent results in a thermal recording medium of high reliability and high head matching quality while preventing, for example, the medium from sticking when contacting the thermal head.
  • the protective layer of the present invention comprises resin having substantially the same refractive index as that of the binder resin forming the thermal recording layer. An acceptable difference between those refractive indexes, which are substantially equal to each other, ranges from approximately -5% to +5%.
  • the resin preferably has the refractive index ranging from 1.45 to 1.60 at ordinary temperature.
  • the resin satisfying the above-mentioned requirement can be selected from water-soluble resin, aqueous resin emulsion, hydrophobic resin, ultraviolet curable resin and electron beam curable resin.
  • the water-soluble resin may be selected from polyvinyl alcohol, denatured polyvinyl alcohol, cellulose derivatives (methylcellulose, methoxycellulose, hydroxyethylcellulose and so on), casein, gelatin, polyvinyl pyrrolidone, styrene-maleic anhydride copolymer, diisobutylene-maleic anhydride copolymer, polyacrylamide, modified polyacrylamide, methylvinyl ether-maleic anhydride copolymer, carboxy modified polyethylene, polyvinyl alcohol/acrylamide block copolymer, melamine-formaldehyde resin, urea-formaldehyde resin and so on.
  • the aqueous resin emulsion and the hydrophobic resin may be selected from polyvinyl acetate, polyurethane, styrene/butadiene-copolymer, styrene/butadiene/acryl-copolymer, polyacrylic acid, polyacrylate, vinyl chloride/vinylacetate-copolymer, polybutyl methacrylate, ethylene/vinylacetate-copolymer and so on. These resins can be used individually or mixed together, and a hardner may also be added to the resin to harden the resin.
  • the monomer or oligomer may be selected from (poly)ester acrylate, (poly)urethane acrylate, epoxy acrylate, polybutadiene acrylate, silicone acrylate and melamine acrylate.
  • Poly ester acrylate is a reaction product of polyhydric alcohol such as 1,6-hexanediol, propylene glycol (in the form of propylene oxide) and diethylene glycol; polybasic acid such as adipic acid, phthalic anhydride and trimellitic acid; and acrylic acid.
  • the solvent is, for example, selected from organic solvents such as tetrahydrofuran, methyl ethyl keton, methyl isobutyl keton, chloroform, carbon tetrachloride, ethanol, isopropyl alcohol, ethyl acetate, butyl acetate, toluene, benzene and so on.
  • a photopolymerizable monomer can be used as a reactive diluent to achieve an easy treatment.
  • the photopolymerizable monomer may be selected from 2-ethylhexyl acrylate, cyclohexyl acrylate, butoxyethyl acrylate, neopentylglycol diacrylate, 1,6-hexanediol diacrylate, polyethyleneglycol diacrylate, trimethylolpropane triacrylate, pentaerythrite acrylate and so on.
  • the electron beam curable resin comprises a branched molecular structure having more than 5 functional groups of a polyester skeleton (hereinafter referred to as "electron beam curable acryl-modified polyurethane resin"), and another preferred embodiment is one which essentially consists of silicone-modified electron beam curable resin.
  • the electron beam curable acryl-modified polyurethane resin for example, can be produced as follows.
  • polyester diol of a reaction product of 1,4-butanediol with adipic acid or another reaction product of propyleneglycol with adipic acid (both of them corresponding to the polyester skeleton) is mixed with polyether triol to achieve a mixture.
  • diisocyanate and a compound having an acrylic double bond are added to the mixture to react with the mixture, so as to produce the electron beam curable acryl-modified polyurethane resin.
  • a mixture of polyester diol with polyether triol, a mixture of polyester diol with polyester triol or polyether diol with polyester triol can be employed to prepare the electron beam curable acryl-modified polyurethane resin as an alternative to the mixture of the polyester diol with the polyether triol.
  • the diisocyanate may be selected from 2,4-tolylenediisocyanate, 2,6-tolylenediisocyanate, 1,6-hexamethylenediisocyanate, xylenediisocyanate, isophoronediisocyanate, methylenebis(4-phenylisocyanate) and so on.
  • the compound having the acrylic double bond for example, can be selected from 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate, 3-hydroxypropyl(meth)acrylate and so on.
  • Polyester diol is commercially available, for example, in the form of ADECANEWACE® Y4-30 (produced by ASAHI DENNKAKOGYO Corp.) and polyether triol is also commercially available, for example, in the form of SUNNIX® TP-400 or SUNNIX® GP-3000 (produced by SANYO KASEI Corp.).
  • the molecular weight of the polyester portion of the electron beam curable acryl-modified polyurethane resin preferably ranges from 2000 to 4000 in order to achieve a desired flexibility and robustness in a heat resistant slip layer. Further, the total molecular weight of the electron beam curable acryl-modified polyurethane resin preferably ranges from 20000 to 50000 for the same reason as described above. A resin having not less than 5 functional groups, and preferably 7 to 13 functional groups, can effectively cause a progress for hardening and an improvement of hardness.
  • the silicone-modified electron beam curable resin may be written as the following formula: where R represents -(CH 2 ) n -, where n represents an integer varying from 0 to 3; TDI represents 2,4-tolylenediisocyanate; and HEM represents 2-hydroxyethyl acrylate, x ranges from 50 to 100 and y ranges from 3 to 6.
  • This silicone-modified electron beam curable resin has a superior covering property to form a uniform thin coating fairly well and has an effective slip property due to a silicone functional group.
  • the electron beam curable acryl-modified resin and the electron beam curable silicone-modified resin it is preferable that 30 parts by weight, and more preferably 5 to 20 parts by weight, of electron beam curable silicone-modified resin may be added to 100 parts by weight of electron beam curable acryl-modified resin.
  • a multi-functional electron beam curable monomer is employed simultaneously in order to promote the progress of the hardening while forming the layer and to improve the heat resistance of the layer.
  • This monomer acts as a cross-linking stimulator and has the advantage of forming a complicated and high-density cross-linked structure.
  • the above-mentioned monomer can be selected from trimethylolpropaneacrylate, tetramethylolmethanetetraacrylate, pentaerythritoltriacrylate, dipentaerythritolhexatriacrylate and so on.
  • A represents a polymerization curable group of the following formula such as a methacryloyloxyethyl group: where R 1 , R 2 , R 3 , R 4 and R 5 are selected from a hydrogen atom, a chlorine atom, a bromine atom and a halogenated alkyl group having from 1 to 4 carbon atoms; M is selected from an oxygen atom, a sulfur atom and an imino group.
  • One of the above-mentioned phosphazene resins where A is a methacryloyloxyethyl group and b is equal to 0, can be prepared by a ring-opening polymerization of a compound of the following formula:
  • the resin has the polymerization curable group as is the case with the phosphazene resin, mechanical strength, hardness and heat resistance of the resin can be improved by hardening with ultraviolet rays , electron rays or heat.
  • the improvement of light stability of the protective layer according to the present invention is also achieved by the protective layer containing the same light stabilizer as that contained in the thermal recording layer as described above.
  • the light stabilizer can be selected from the ultraviolet absorber, the antioxidant, the anti-aging agent, the extinctive agent of the singlet enzyme and the extinctive agent of the superoxide anion, which are all the same as those employed with the thermal recording layer.
  • the organic filler employed in the present invention may be selected from polyolefin particles, polystyrene particles, urea-formaldehyde resin particles and plastic fine hollow spherical particles; and the inorganic filler may be selected from aluminium hydroxide, heavy and light calcium carbonate, zinc oxide, titanium oxide, barium sulfate, silica gel, colloidal silica (from 10 to 50 nm), alumina sol (from 10 to 200 nm), activated clay, talc, clay titanium white, kaolinite, calcined kaolinite, diatomaceous earth, synthetic kaolinite, zirconium compounds and glass fine hollow spheres.
  • a spherically shaped filler having the same slip property as that of Si resin or fluorine resin is preferably employed.
  • a slip additive may be selected from a slip agent such as silicone oil, a surfactant, an organic salt and a class of waxes; and a slip filler.
  • the silicone oil may be selected from dimethylpolysiloxane, methylphenylpolysiloxane, methylhydrodienepolysiloxane, alkyl-modified polysiloxane, carbon-modified polysiloxane and alcohol-modified polysiloxane.
  • the surfactant may be selected from a commercially available carboxylate, sulfate ester salt of higher alcohol, sulfonate, phosphate of higher alcohol and salt thereof.
  • Non-limiting embodiments of the surfactant are sodium laurate, sodium stearate, sodium oleate, lauryl alcohol sodium sulfate ester, myristyl alcohol sodium sulfate ester, cetyl alcohol sodium sulfate ester, stearyl alcohol sodium sulfate ester, oleyl alcohol sodium sulfate ester, sodium sulfate ester of an ethylene oxide adduct of higher alcohol, sodium octylsulfonate, sodium decylsulfonate, sodium dodecylsulfonate, sodium octylbenzene sulfonate, sodium dodecylbenzene sulfonate, potassium dodecylbenzene sulfonate, sodium nony
  • the organic salts may be selected from metal soaps such as zinc stearate, aluminium stearate, calcium stearate, magnesium stearate; and a class of salts such as hexylammoniumchloride, sodium sulfosalicylate, sodium succinate, potassium succinate, potassium benzonate and potassium adipate.
  • metal soaps such as zinc stearate, aluminium stearate, calcium stearate, magnesium stearate
  • a class of salts such as hexylammoniumchloride, sodium sulfosalicylate, sodium succinate, potassium succinate, potassium benzonate and potassium adipate.
  • the wax may be selected from natural wax such as candelilla wax, carnauba wax, rice wax, bees wax, lanolin wax, montan wax, paraffin wax and microcrystalline wax; and synthetic wax such as polyethylene wax, hydrogenated castor oil and derivatives thereof and fatty acid amide.
  • An appropriate amount of the slip agent in the protective layer ranges from 0.001 to 15.0% by weight. If the amount of the slip agent exceeds the appropriate range, the mechanical strength of the protective layer degrades, and if the amount is less than the appropriate one, an effect of the slip agent can not be achieved.
  • the transparent thermal recording medium according to the present invention can be prepared with one of the following methods.
  • First the coating liquid is prepared in accordance with each of the following methods.
  • the first method solely the developer is homogeneously dispersed in the organic solvent, and then the color-producing agent and the binder resin successively are homogeneously mixed with the solvent to prepare the coating liquid for the thermal recording layer.
  • the second method the developer is homogeneously dispersed in a solution of the binder resin, in which the binder resin is dissolved in the organic solvent, and the coating liquid for the thermal recording layer is prepared by homogeneously mixing the color-producing agent and so on with the solution.
  • the color-producing agent and the developer are dispersed in the organic solvent with the binder resin to prepare the coating liquid for the thermal recording layer. Then the coating liquid having been dispersed homogeneously by one of the above-mentioned ways is applied and dried on one side or both sides of the transparent support so as to provide the thermal recording layer on the support, and then the protective layer consisting essentially of resin is provided on the thermal recording layer.
  • the organic solvent for dissolving the binder resin can be selected from ethers such as dibutylether, isopropylether, dioxane and tetrahydrofuran; ketones such as acetone, diethylketone, methylethylketone, methylisobutylketone and methylpropylketone; esters such as ethyl acetate, isopropyl acetate and n-propyl acetate; and aromatic hydrocarbons such as benzene, toluene and xylene.
  • ethers such as dibutylether, isopropylether, dioxane and tetrahydrofuran
  • ketones such as acetone, diethylketone, methylethylketone, methylisobutylketone and methylpropylketone
  • esters such as ethyl acetate, isopropyl acetate and n-propyl a
  • the protective layer requires the thickness of the applied layer on the thermal recording medium to be from 0.1 to 20 ⁇ m, and preferably from 0.5 to 10 ⁇ m,so as to achieve enough performance of the protective layer and keep a capacity of the thermal recording medium.
  • an antistatic layer is provided on the back side of the recording medium for easy handling thereof, preventing dust from being attached to the recording medium and improving image quality.
  • electrostatic agent suitable even at low temperature electrically conductive metal oxide compounds can be mentioned.
  • an antistatic agent including electrically conductive metal oxide is expensive.
  • the metal oxide compound itself is electrically conductive, even a small amount of metal oxide compound affords great antistatic characteristics.
  • a metal oxide compound does not prevent the production of a transparent recording medium.
  • the electrically conductive metal oxide SnO 2 , In 2 O 3 , ZnO, TiO 2 , MgO, Al 2 O 3 , BaO or MoO 3 can be used solely or these compounds can be used with P, Sb, Sn or Zn.
  • the electrically conductive metal oxide is not limited to those listed above. It is preferred that particles of the electrically conductive metal oxide are fine to realize a transparent recording medium. In this invention, the average particle size is less than 0.2 ⁇ m to realize a transparent recording medium.
  • hydrophilic resin As binders to be used with the above metal oxides, hydrophilic resin, hydrophilic emulsion, hydrophobic resin, ultraviolet curable resin and electron beam curable resin can be mentioned.
  • hydrophilic resin polyvinylalcohol, cellulose derivative, casein, gelatin, styrene-maleic acid anhydride, carboxy-denatured polyethylene resin can be mentioned.
  • hydrophilic emulsion and the hydrophobic resin polyvinylacetate, polyurethane, vinyl chloride/vinyl acetate-copolymer, polyester, polybutylacrylate, polyvinylacetal, ethylene/vinylacetate-copolymer can be mentioned.
  • One of those compounds solely or a mixture of several of the compounds can be employed.
  • a hardener can be used with those compounds if necessary.
  • An image to be recorded on the transparent thermal recording medium according to the present invention can be formed in various ways by using, for example, a thermal pen, a thermal head, laser heating, or thermal etching with light, according to a purpose of image usage. In practice it is preferable that the thermal head is employed to form the image.
  • the transparent thermal recording medium is suitable for a thermal recording medium for a block copy.
  • a thermal recording medium for a block copy comprising, a transparent supporting member, and a thermal recording layer provided on said transparent supporting member, said thermal recording layer including an electron-donating chromophoric compound, an organic phosphoric compound and a binder resin having a refractive index ranging from 1.45 to 1.60, said binder resin including a hydroxyl group and/or a carboxyl group in a molecule thereof, and a protective layer provided on said thermal recording layer, said protective layer consisting essentially of a resin having a refractive index similar to that of said binder resin at ordinary temperature, wherein the difference in light transmission factors between a color-producing imaging portion formed by thermal energy and a non-imaging portion is over 35% at a wavelength ranging from 350nm to 470nm, can be used.
  • a thermal recording medium for a block copy comprising a transparent supporting member, and a thermal recording layer provided on said transparent supporting member, said thermal recording layer including an electron-donating chromophoric compound, an organic phosphoric compound and a binder resin having a refractive index ranging from 1.45 to 1.60, said binder resin including a hydroxyl group and/or a carboxyl group in a molecule thereof, and a protective layer provided on said thermal recording layer, said protective layer consisting essentially of a resin having a refractive index similar to that of said binder resin at ordinary temperature, wherein the difference in light transmission factors between a color-producing imaging portion formed by thermal energy and a non-imaging portion is over 35% at a wavelength ranging from 380nm to 440nm.
  • the present invention is not limited to the above-described media.
  • a coating liquid for the recording layer was prepared by dispersing the following composition with a desk-top type ball mill so as to yield a 0.3 ⁇ m average particle size of octadecylphosphonic acid.
  • a coating liquid for the protective layer was prepared by dispersing the following composition homogeneously.
  • the coating liquid for the recording layer was applied and dried on a 100 ⁇ m HPJ polyester film (produced by Teijin Corp.) by a wire bar so as to yield a 6.0 ⁇ m thickness of the applied coating layer, and thus forming the thermal recording layer. Further, the coating liquid for the protective layer was applied and dried on the thermal recording layer with the wire bar, and then hardened with a 80W/cm ultraviolet ray lamp to form the protective layer of about 6.0 ⁇ m in thickness. Thus a transparent thermal recording medium was produced.
  • a coating liquid for the recording layer was prepared by dispersing the following composition with a desk-top type ball mill so as to yield a 0.3 ⁇ m average particle size of octadecylphosphonic acid.
  • a coating liquid for the protective layer was prepared by dispersing the following composition homogeneously.
  • the coating liquid for the recording layer was applied and dried on a 100 ⁇ m HPJ polyester film (produced by Teijin Corp.) by a wire bar so as to yield an 8.0 ⁇ m thickness of the applied coating layer, and thus forming the thermal recording layer. Further, the coating liquid for the protective layer was applied and dried on the thermal recording layer with a wire bar, and then hardened with an 80W/cm ultraviolet ray lamp to form the protective layer of about 6.0 ⁇ m in thickness. Thus a transparent thermal recording medium was produced.
  • a coating liquid for the recording layer was prepared by dispersing the following composition with a desk-top type ball mill so as to yield a 0.3 ⁇ m average particle size of eicosylphosphonic acid.
  • a coating liquid for the protective layer was prepared by dispersing the following composition homogeneously.
  • the coating liquid for the recording layer was applied and dried on a 100 ⁇ m HPJ polyester film (produced by Teijin Corp.) by a wire bar so as to yield an 8.0 ⁇ m thickness of the applied coating layer, and thus forming the thermal recording layer. Further, the coating liquid for the protective layer was applied and dried on the thermal recording layer with a wire bar, and then hardened with an 80W/cm ultraviolet ray lamp to form a protective layer of about 6.0 ⁇ m in thickness. Thus a transparent thermal recording medium was produced.
  • a coating liquid for the recording layer was prepared by dispersing the following composition with a desk-top type ball mill so as to yield a 0.3 ⁇ m average particle size of eicosylphosphonic acid.
  • a coating liquid for the protective layer was prepared by dispersing the following composition homogeneously.
  • the coating liquid for the recording layer was applied and dried on a 100 ⁇ m HPJ polyester film (produced by Teijin Corp.) by a wire bar so as to yield an 8.0 ⁇ m thickness of the applied coating layer, and thus forming the thermal recording layer. Further, the coating liquid for the protective layer was applied and dried on the thermal recording layer with a wire bar, and then hardened with an 80W/cm ultraviolet ray lamp to form a protective layer of about 6.0 ⁇ m in thickness. Thus a transparent thermal recording medium was produced.
  • a coating liquid for the recording layer was prepared by dispersing the following composition with a desk-top type ball mill so as to yield a 0.3 ⁇ m average particle size of octadecylphosphonic acid.
  • a coating liquid for the protective layer was prepared by dispersing the following composition homogeneously.
  • the coating liquid for the recording layer was applied and dried on a 100 ⁇ m HPJ polyester film (produced by Teijin Corp.) by a wire bar so as to yield an 8.0 ⁇ m thickness of the applied coating layer, and thus forming the thermal recording layer. Further, the liquid for the protective layer was applied and dried on the thermal recording layer with the wire bar, and then hardened with an 80-W/cm ultraviolet ray lamp to form a protective layer of about 6.0 ⁇ m in thickness. Thus a transparent thermal recording medium was produced.
  • a coating liquid for the recording layer was prepared by dispersing the following composition with a desk-top type ball mill so as to yield a 0.3 ⁇ m average particle size of octadecylphosphonic acid.
  • a coating liquid for the protective layer was prepared by dispersing the following composition homogeneously.
  • the coating liquid for the recording layer was applied and dried on a 100 ⁇ m HPJ polyester film (produced by Teijin Corp.) by a wire bar so as to yield an 8.0 ⁇ m thickness of the applied coating layer, and thus forming the thermal recording layer. Further, the coating liquid for the protective layer was applied and dried on the thermal recording layer with a wire bar, and then hardened with a 80W/cm ultraviolet ray lamp to form a protective layer of about 6.0 ⁇ m in thickness. Thus a transparent thermal recording medium was produced.
  • a coating liquid for the recording layer was prepared by dispersing the following composition with a desk-top type ball mill so as to yield a 0.3 ⁇ m average particle size of octadecylphosphonic acid.
  • a coating liquid for the protective layer was prepared by dispersing the following composition homogeneously.
  • the coating liquid for the recording layer was applied and dried on a 100 ⁇ m HPJ polyester film (produced by Teijin Corp.) by a wire bar so as to yield an 8.0 ⁇ m thickness of the applied coating layer, and thus forming the thermal recording layer. Further, the applied liquid for the protective layer was applied and dried on the thermal recording layer with a wire bar, and then hardened with a 80W/cm ultraviolet ray lamp to form a protective layer of about 6.0 ⁇ m in thickness. Thus a transparent thermal recording medium was produced.
  • a coating liquid for the recording layer was prepared by dispersing the following composition with a desk-top type ball mill so as to yield a 0.3 ⁇ m average particle size of eicosylphosphonic acid.
  • a coating liquid for the protective layer was prepared by dispersing the following composition homogeneously.
  • the coating liquid for the recording layer was applied and dried on a 100 ⁇ m HPJ polyester film (produced by Teijin Corp.) by a wire bar so as to yield a 8.0 ⁇ m thickness of the applied coating layer, and thus forming the thermal recording layer. Further, the coating liquid for the protective layer was applied and dried on the thermal recording layer with a wire bar, and then hardened with a 80W/cm ultraviolet ray lamp to form a protective layer of about 6.0 ⁇ m in thickness. Thus a transparent thermal recording medium was produced.
  • a coating liquid for the recording layer was prepared by dispersing the following composition with a desk-top type ball mill so as to yield a 0.3 ⁇ m average particle size of octadecylphosphonic acid.
  • a coating liquid for the protective layer was prepared by dispersing the following composition homogeneously.
  • the coating liquid for the recording layer was applied and dried on a 100 ⁇ m HPJ polyester film (produced by Teijin Corp.) by a wire bar so as to yield a 8.0 ⁇ m thickness of the applied coating layer, and thus forming the thermal recording layer. Further, the coating liquid for the protective layer was applied and dried on the thermal recording layer with a wire bar, and then hardened with a 80W/cm ultraviolet ray lamp to form a protective layer of about 6.0 ⁇ m in thickness. Thus a transparent thermal recording medium was produced.
  • a coating liquid for the recording layer was prepared by dispersing the following composition with a desk-top type ball mill so as to yield a 0.3 ⁇ m average particle size of octadecylphosphonic acid.
  • a coating liquid for the protective layer was prepared by dispersing the following composition homogeneously.
  • the coating liquid for the recording layer was applied and dried on a 100 ⁇ m HPJ polyester film (produced by Teijin Corp.) by a wire bar so as to yield a 80 ⁇ m thickness of the applied coating layer, and thus forming the thermal recording layer. Further, the coating liquid for the protective layer was applied and dried on the thermal recording layer with the wire bar, and then hardened with the 80W/cm ultraviolet ray lamp to form a protective layer of about 6.0 ⁇ m in thickness. Thus a transparent thermal recording medium was produced.
  • a coating liquid for the recording layer was prepared by dispersing the following composition with a desk-top type ball mill so as to yield a 0.3 ⁇ m average particle size of eicosylphosphonic acid.
  • 2-(o-chlorophenylamino)-6-n-octylaminofuran 10 prats Eicosylphosphonic acid 30 parts Styrene/maleic acid monoisobutyl ester-copolymer [refractive index 1.57, produced by Gifu Cerac Corp.] 15 parts Mixed liquid of toluene/methylethylketone (ratio 1/4) 285 parts
  • a coating liquid for the protective layer was prepared by dispersing the following composition homogeneously.
  • urethane acrylate ultraviolet curable resin [refractive index 1.56] in n-butyl acetate solution (Unidick C7-157 produced by Dainihon Ink Kagaku Corp.] 100 parts Xylene solution of 52% silicone resin (Byk-344 produced by Byk Chemy Japan Corp.) 4 parts Colloidal silica gel (Mizucasil® P-527 produced by Mizusawa Kagaku Corp.) 20 parts Ethylacetate 50 parts
  • the coating liquid for the recording layer was applied and dried on a 75 ⁇ m Melinex® 705 polyester film (produced by ICI Japan Inc.) by a wire bar so as to yield a 8.0 ⁇ m thickness of the applied coating layer, and thus forming the thermal recording layer. Further, the coating liquid for the protective layer was applied and dried on the thermal recording layer with a wire bar, and then hardened with a 80W/cm ultraviolet ray lamp to form a protective layer of about 4.0 ⁇ m in thickness. Thus, a transparent thermal recording medium was produced.
  • a coating liquid for the recording layer was prepared by dispersing the following composition with a desk-top type bail mill so as to yield a 0.3 ⁇ m average particle size of octadecylphosphonic acid.
  • a coating liquid for the protective layer was prepared by dispersing the following composition homogeneously.
  • Silicone-denatured polyvinylbutyral SP-712 produced by Dainichiseika Corp., solids content 12.5%
  • SP-712 produced by Dainichiseika Corp., solids content 12.5%
  • SnO 2 -Sb/vinyl chloride resin (ELCOM 3519-3 produced by Shokubai Kasei Kogyo Inc.) 20 parts Mixed liquid of toluene/methylethylketone (ratio 1/1) 80 parts
  • the coating liquid for the antistatic layer was applied and dried on one side of a 75 ⁇ m Melinex® 705 polyester film (produced by ICI Japan Corp.) by a wire bar so as to yield a 0.3 ⁇ m thickness of the applied antistatic layer.
  • the coating liquid for the recording layer was applied and dried on the other side of the polyester film by a wire bar so as to yield an 8.0 ⁇ m thickness of the applied coating layer, and thus forming the thermal recording layer.
  • the coating liquid for the protective layer was applied and dried on the thermal recording layer with a wire bar to form a protective layer of about 2.0 ⁇ m in thickness. Thus, a transparent thermal recording medium was produced.
  • a coating liquid for the recording layer was prepared by dispersing the following composition with a desk-top type ball mill so as to yield a 1.3 ⁇ m average particle size of octadecylphosphonic acid.
  • the coating liquid for the recording layer was applied and dried on the 100 ⁇ m HPJ polyester film (produced by Teijin Corp.) by a wire bar, and thus a thermal recording medium was produced.
  • a transparent thermal recording medium according to Control 2 was prepared similarly to Example 1 except that polyvinylbutyral was replaced by a polyvinyl chloride-vinyl acetate copolymer [refractive index: 1.54] (UYHH: produced by Union Carbide Corp.).
  • a transparent thermal recording medium according to Control 3 was prepared similarly to the Example 1 except that polyvinylbutyral was replaced by saturated polyester Byron® 300 [refractive index: 1.56] (produced by Toyobo Corp.).
  • a transparent thermal recording medium according to Control 4 was prepared similarly to Example 1 except that polyvinylbutyral was replaced by acryl resin Dianal® BR-85 [refractive index: 1.49] (produced by Mitsubishi Kasei Corp.).
  • the color tone of each of the recorded images was visually inspected immediately after being recorded.
  • the image density and the non-printed surface density for each of the recorded images were measured by a transparent densitometer X-Rite 310TR (produced by X-RITE COMPANY) operating in VISUAL mode.
  • Spectral transmission factors for a colored imaging portion and a non-imaging portion (non-printed surface) of the thermal recording media were measured by a spectrophotometer UV-3100 produced by Simazu Seisakusyo at spectral wavelengths of 380 nm, 440 nm and 550 nm.
  • the films produced in the above-mentioned examples, in which the images were formed thereon with the thermal head were used for positive films (block copy films) for screen process printing, and thus blocks for the screen process printing were produced. Images were printed on the blocks with an easy mimeograph machine and the block copy films were evaluated as regards capability for printing.
  • the transparent thermal recording medium according to the present invention can be effectively used for the block copy film, on which images are formed, for plate-making, particularly, in photogravure, offset printing and screen process printing, because the transparent thermal recording medium has a difference in light transmission factors between the color-imaging portion and the non-imaging portion of not less than 50% at the wavelength ranging from 370 nm to 450 nm.

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Claims (8)

  1. Milieu d'enregistrement thermique transparent comprenant : une couche d'enregistrement thermique, qui est réalisée sur une couche transparente et qui comprend un composé chromophore donneur d'électrons, un composé accepteur d'électrons et une résine liant ; et
    une couche protectrice réalisée en outre ayant un indice de réfraction sensiblement égal à l'indice de réfraction de ladite couche d'enregistrement thermique,
    caractérisé en ce que ladite résine liant est un composé ayant un groupe hydroxyle et/ou un groupe carboxyle.
  2. Milieu d'enregistrement thermique transparent tel que revendiqué dans la revendication 1, caractérisé en ce que l'indice de réfraction de ladite résine liant et l'indice de réfraction de la résine formant ladite couche protectrice se trouvent dans la gamme de 1,45 à 1,60 à température ordinaire.
  3. Milieu d'enregistrement thermique transparent tel que revendiqué dans la revendication 1 ou 2, caractérisé en ce que ledit composé accepteur d'électrons est un composé d'acide phosphorique organique.
  4. Milieu d'enregistrement thermique transparent tel que revendiqué dans la revendication 3, caractérisé en ce que ledit composé d'acide phosphorique organique est choisi parmi les composés d'acide phosphonique de formule générale (I) et formule générale (II) suivantes :
    Figure 00840001
    formule dans laquelle R est choisi parmi des groupes alkyle linéaires ayant de 16 à 24 atomes de carbone ; et
    Figure 00850001
    formule dans laquelle R' est choisi parmi des groupes alkyle linéaires ayant de 13 à 23 atomes de carbone.
  5. Milieu d'enregistrement thermique transparent tel que revendiqué dans les revendications 1 à 4, caractérisé en ce que ledit composé chromophore donneur d'électrons est choisi parmi les composés de fluorane de formules générales suivantes (III), (IV), (V), (VI), (VII) et (VIII) :
    Figure 00850002
    formule dans laquelle R1 est choisi parmi des groupes alkyle ayant 8 atomes de carbone ou moins, R2 est choisi parmi un atome d'hydrogène et un groupe alkyle ayant 4 atomes de carbone ou moins et X représente un atome d'halogène choisi parmi un atome de fluor, un atome de chlore et un atome de brome ;
    Figure 00860001
    formule dans laquelle R3 est choisi parmi un atome d'hydrogène et un groupe alkyle ayant 8 atomes de carbone ou moins et R4 est choisi parmi des groupes alkyle ayant 8 atomes de carbone ou moins ;
    Figure 00860002
    formule dans laquelle R5 et R6 sont choisis parmi des groupes alkyle ayant 8 atomes de carbone ou moins, et R7 est choisi parmi un atome d'hydrogène, un groupe alkyle inférieur et un groupe alcoxy inférieur ;
    Figure 00860003
    formule dans laquelle R8 représente un atome d'hydrogène, R9 représente un groupe alkyle ayant 8 atomes de carbone ou moins, R10 est choisi parmi un atome d'hydrogène, un groupe alkyle inférieur et un groupe alcoxy inférieur, R11 est choisi parmi un atome d'hydrogène et un groupe alkyle ayant 8 atomes de carbone ou moins et R12 est choisi parmi un groupe alkyle ayant 8 atome de carbone ou moins, un groupe phényle et un groupe phényle substitué ;
    Figure 00870001
    formule dans laquelle R13 représente un groupe alkyle ayant 8 atomes de carbone ou moins, R14 est choisi parmi un groupe méthyle et un groupe éthyle, R15 est choisi parmi un atome d'hydrogène et un groupe alkyle ayant 4 atomes de carbone ou moins, et Y et Z sont choisis parmi des atomes d'halogène, tels que des atomes de fluor, des atomes de chlore et des atomes de brome ; et
    Figure 00870002
    formule dans laquelle R16 représente un groupe alkyle ayant 8 atomes de carbone ou moins, R17 est choisi parmi un groupe méthyle et un groupe éthyle, R18 est choisi parmi un groupe alkyle ayant 4 atomes de carbone ou moins et un atome d'halogène tel qu'un atome de fluor, un atome de chlore et un atome de brome, et Ar est choisi parmi un groupe phényle et un groupe benzyle.
  6. Milieu d'enregistrement thermique transparent comprenant : une couche d'enregistrement thermique réalisée sur un support transparent, caractérisé en ce que ladite couche d'enregistrement thermique consiste essentiellement en un composé chromophore donneur d'électrons, un composé d'acide phosphorique organique et une résine liant ayant un indice de réfraction se trouvant dans la gamme de 1,45 à 1,60 à température ordinaire et comprenant un groupe hydroxyle et/ou un groupe carboxyle ; et
    une couche protectrice réalisée sur ladite couche d'enregistrement thermique, ladite couche protectrice consistant essentiellement en une résine ayant un indice de réfraction se trouvant dans la gamme de 1,45 à 1,60 à température ordinaire.
  7. Milieu d'enregistrement thermique pour copie en bloc, comprenant :
    un élément de support transparent ; et
    une couche d'enregistrement thermique réalisée sur ledit élément de support transparent, ladite couche d'enregistrement thermique comprenant un composé chromophore donneur d'électrons, un composé d'acide phosphorique organique et une résine liant ayant un indice de réfraction se trouvant dans la gamme de 1,45 à 1,60, ladite résine liant comprenant un groupe hydroxyle et/ou un groupe carboxyle dans sa molécule, et une couche protectrice réalisée sur ladite couche d'enregistrement thermique, ladite couche protectrice consistant essentiellement en une résine ayant un indice de réfraction similaire à celui de ladite résine liant à température ordinaire,
    dans lequel la différence des facteurs de transmission de lumière entre une partie d'image produisant une couleur formée par énergie thermique et une partie sans image est supérieure à 35 % à une longueur d'onde se trouvant dans la gamme de 350 nm à 470 nm.
  8. Milieu d'enregistrement thermique pour copie en bloc, comprenant :
    un élément de support transparent ; et
    une couche d'enregistrement thermique réalisée sur ledit élément de support transparent, ladite couche d'enregistrement thermique comprenant un composé chromophore donneur d'électrons, un composé d'acide phosphorique organique et une résine liant ayant un indice de réfraction se trouvant dans la gamme de 1,45 à 1,60, ladite résine liant comprenant un groupe hydroxyle et/ou un groupe carboxyle dans sa molécule, et une couche protectrice réalisée sur ladite couche d'enregistrement thermique, ladite couche protectrice consistant essentiellement en une résine ayant un indice de réfraction similaire à celui de ladite résine liant à température ordinaire,
    dans lequel la différence des facteurs de transmission de lumière entre une partie d'image produisant une couleur formée par énergie thermique et une partie sans image est supérieure à 35 % à une longueur d'onde se trouvant dans la gamme de 380 nm à 440 nm.
EP19950108850 1994-06-09 1995-06-08 Elément transparent pour enregistrement thermique Expired - Lifetime EP0688680B2 (fr)

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JPH11254826A (ja) 1998-03-09 1999-09-21 Fuji Photo Film Co Ltd 感熱記録材料
JP3710299B2 (ja) 1998-10-19 2005-10-26 富士写真フイルム株式会社 感熱記録材料
PT1010542E (pt) * 1998-12-18 2003-12-31 Ricoh Kk Material de registo termossensivel
JP2019111726A (ja) * 2017-12-22 2019-07-11 株式会社リコー 感熱記録媒体、感熱記録媒体の製造方法、及び物品

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1182743A (en) * 1967-01-27 1970-03-04 Fuji Photo Film Co Ltd Fluoran Compounds and Pressure-Sensitive Copying Paper containing them
JPH05104859A (ja) * 1991-10-15 1993-04-27 Ricoh Co Ltd 透明感熱記録媒体
JPH05345475A (ja) * 1992-06-17 1993-12-27 New Oji Paper Co Ltd 製版用および投影用の原図フィルム
JPH0679970A (ja) * 1992-03-09 1994-03-22 Ricoh Co Ltd 可逆的多色感熱記録媒体及び表示媒体、それらの媒体を用いる可逆的多色画像形成方法と初期化方法、それらの方法を実施するための装置及び可逆的多色熱発色性組成物
US5380693A (en) * 1993-04-02 1995-01-10 Ricoh Company, Ltd. Transparent thermosensitive recording medium
JPH08224962A (ja) * 1995-02-22 1996-09-03 Ricoh Co Ltd 加色型多色感熱記録材料

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61121875A (ja) 1984-11-12 1986-06-09 チヤネルロツク　インコ−ポレイテツド すべり接続プライヤ
JPH074986B2 (ja) * 1986-05-26 1995-01-25 富士写真フイルム株式会社 感熱記録材料
JPH0825335B2 (ja) 1987-10-13 1996-03-13 富士写真フイルム株式会社 感熱記録材料

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1182743A (en) * 1967-01-27 1970-03-04 Fuji Photo Film Co Ltd Fluoran Compounds and Pressure-Sensitive Copying Paper containing them
JPH05104859A (ja) * 1991-10-15 1993-04-27 Ricoh Co Ltd 透明感熱記録媒体
JPH0679970A (ja) * 1992-03-09 1994-03-22 Ricoh Co Ltd 可逆的多色感熱記録媒体及び表示媒体、それらの媒体を用いる可逆的多色画像形成方法と初期化方法、それらの方法を実施するための装置及び可逆的多色熱発色性組成物
JPH05345475A (ja) * 1992-06-17 1993-12-27 New Oji Paper Co Ltd 製版用および投影用の原図フィルム
US5380693A (en) * 1993-04-02 1995-01-10 Ricoh Company, Ltd. Transparent thermosensitive recording medium
JPH08224962A (ja) * 1995-02-22 1996-09-03 Ricoh Co Ltd 加色型多色感熱記録材料

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Journal of Imaging Technology-Vol.16, No.6,Dec. 1990, pages 234 to 237 *
Polymer Handbook, 2nd Edition, 1975, page III-242 *

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DE69508306T2 (de) 1999-09-30

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