JPH0381194A - Thermal transfer dye donating material - Google Patents

Abstract

PURPOSE:To obtain a thermal transfer dye donating material having strong absorbancy in a near infrared region, low in the absorption of a visible region and excellent in fastness by providing a thermal transfer layer containing a specific thermal transfer dye on a support. CONSTITUTION:A thermal transfer layer containing a thermal transfer dye represented by formula (I) along with a binder is provided on a support. In the formula (I), R1 is a halogen atom, an alkoxy group, an aryloxy group, an acylamino group, an alkoxycarbonylamino group, a sulfonylamino group, a sulfamoyl group, a hydroxyl group, a sulfonyl group or an ureido group, n is an integer of 0-3, R1 may be same or different when n is 2 or 3, R2 and R3 may be same or different and are an alkyl group, an alkoxy group, a halogen atom, an acylamino group, an alkoxycarbonylamino group or an ureido group and X is a cyano group, an acyl group, an alkoxycarbonyl group, a carbamoyl group or a sulfonyl group.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a thermal transfer dye-providing material for thermal transfer recording, and in particular to a thermal transfer dye-providing material using a heat-transferable dye that absorbs in the near-infrared region. It is related to.

(Background Art) In recent years, with the rapid development of the information industry, various information processing systems have been developed, and recording methods and devices suitable for each information processing system have also been developed and adopted. The thermal transfer recording method is one of these recording methods, and has recently become widely used because the equipment used is lightweight, compact, noiseless, has excellent operability and maintainability, and can be easily converted to color. . This thermal transfer recording method can be roughly divided into two types: a thermal melting type and a thermal transfer type. In the latter method, a thermal transfer dye-providing material having a dye-providing layer containing a binder and a heat-transferable dye on a support is superimposed on a thermal transfer image-receiving material, and heat is applied from the support side of the dye-providing material to create a pattern formed by the thermal application. This is a method of obtaining a transferred image by transferring a heat-transferable dye onto a recording medium (thermal transfer image-receiving material).

Note that the term "thermally transferable dye" as used herein refers to a dye that can be transferred from a thermal transfer dye-providing material to a thermal transfer image-receiving material by sublimation or diffusion in a medium.

Normally, in the thermal transfer method described above, color images are formed using heat-transferable dyes in the three primary colors of yellow, magenta, and cyan using a subtractive color method, but these dyes emit light in a wavelength range longer than the visible range, that is, in the near-infrared range. has almost no absorption. Generally, the absorption tail of cyan dyes on the long wavelength side extends to 700 nm or more, but no cyan dyes having large absorption in the near-infrared region are known at all.

On the other hand, in recent years, optical character reading devices and label barcode reading devices (hereinafter referred to as OCR devices) have been developed, and their use is increasing. Many of these devices use a light emitting diode or semiconductor laser that emits light with a wavelength of 700 nm or more as a reading light source. In addition, using a tungsten lamp as a light source, it has a light receiving sensitivity peak around 900 nm and a wavelength of 700 to 12 nm.
Optical reading devices using light receiving elements with a sensitivity range of 0.00 nm are also in practical use.

(Problem to be Solved by the Invention) However, since images obtained using conventional thermal transfer dye-providing materials have almost no absorption in the near-infrared region of 700 nm or more, as described above, these reading devices cannot read image information. Impossible or very difficult to read.

Therefore, the light absorption wavelength is 700 nm or more, preferably 700 nm or more.
There has been a strong desire for the development of heat-transferable dyes with a wavelength of 50 nm or more and the development of heat-transferable dye-providing materials using the same.

(Object of the invention) The present invention provides a thermal transfer dye-providing material using a heat-transferable dye that has strong light absorption in the near-infrared region, little absorption in the visible region, and excellent fastness. .

(Means for Solving the Problems) The objects of the present invention have been achieved by a thermal transfer dye-providing material comprising a heat transferable dye represented by the following formula (I) on a support.

λ 4Rs In the above formula, R1 represents a halogen atom, an alkoxy group, an aryloxy group, an acylamino group, an alkoxycarbonylamino group, a sulfonylamino group, a sulfamoyl group, a hydroxyl group, a sulfonyl group, and a ureido group, and n
represents an integer of 0 to 3, and when n is 2 or 3, R1 may be the same or different. R2 and R3 may be the same or different, and represent an alkyl group, an alkoxy group, a norogen atom, an acylamino group, an alkoxycarbonylamino group, or a ureido group, and R4 and R5 may be the same or different, and represent a hydrogen atom. , represents an alkyl group and an aryl group. R4 and R5 may be combined with each other to form a ring. Further, R,, R, may be combined with a benzene ring to form a 5- or 6-membered nitrogen-containing heterocycle.

X represents a cyano group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, or a sulfonyl group. The above substituents may be further substituted with other substituents. The formula CI) will be explained in detail below.

Ro represents a halogen atom (fluorine, chlorine, bromine), an alkoxy group (methoxy group, ethoxy group, etc.), an aryloxy group (phenoxy group, 2-fluorophenoxy group, etc.), an acylamino group (acetylamino group, propionylamino group, fluoroacetylamino group, etc.), alkoxycarbonylamino group (methoxycarbonylamino group, ethoxycarbonylamino group, etc.), sulfonylamino group (methylsulfonylamino group, phenylsulfonylamino group, etc.), sulfamoyl group (N, N-dimethylsulfonyl group) moyl group, N1N-diethylsulfamoyl group, etc.), hydroxyl group, sulfonyl group (methylsulfonyl group, ethylsulfonyl group, etc.), and ureido group (3,3-dimethylureido group, etc.). n represents an integer of 0 to 3, with 0 being particularly preferred. R2 and R3 are hydrogen atoms, alkyl groups (methyl groups, ethyl groups, etc.), alkoxy groups (methoxy groups, ethoxy groups, etc.), halogen atoms (fluorine, chlorine,
bromine, etc.), acylamino groups (acetylamino group, propionylamino group, trifluoroacetylamino group, etc.),
It represents an alkoxycarbonylamino group (methoxycarbonylamino group, ethoxycarbonylamino group, etc.) and a ureido group (3,3-dimethylureido group, 3-methylureido group, etc.). Preferred examples of R6 and R8 are a hydrogen atom, an alkyl group, an alkoxy group, an acylamino group,
and an alkoxycarbonylamino group, among which a hydrogen atom, methyl group, methoxy group, acetylamino group, methoxycarbonylamino group, and ethoxycarbonylamino group are particularly preferred. R, R3 are hydrogen atoms, alkyl groups (ethyl group, methoxyethyl group, hydroxyethyl group, methanesulfonylaminoethyl group, etc.), aryl groups (phenyl group, p-tolyl group, p-methoxyphenyl group, p-chlorophenyl group) groups, etc.), among which alkyl groups are preferable, and preferable specific examples include ethyl groups,
Examples include methanesulfonylaminoethyl group and cyanoethyl group. Also, R.

and R5 bond to form a piperidine ring, and R, bond to a benzene ring to form a tetrahydroquinoline ring as preferred examples. X is a cyano group, an acyl group (acetyl group, propionyl group, benzoyl group, etc.), an alkoxycarbonyl group (methoxycarbonyl group, ethoxycarbonyl group, etc.), a carbamoyl group (N-methylcarbamoyl group, N-phenylcarbamoyl group, etc.), It represents a sulfonyl group (methylsulfonyl group, phenylsulfonyl group, etc.), among which preferable examples include a cyano group, an alkoxycarbonyl group, and a carbamoyl group.

Next, specific examples of the infrared light absorbing dye of the present invention will be shown, but the present invention is not limited thereto.

/- HsCg C*Hs (17) HsC2CJ6 Next, a method for synthesizing the infrared light-absorbing dye of the present invention will be described.

A general synthesis method for the dye of the present invention is a method in which 1-dicyanomethylnaphthalene and its derivatives are oxidatively coupled with p-phenylene diamines, or 4-nitroso-
A method of dehydration and condensation with N,N-disubstituted anilines can be mentioned, but the latter is superior in terms of synthesis yield. A specific synthesis example is shown below.

Synthesis Example, Synthesis of Infrared Light Absorbing Pigment (4) 3.84 g of l-dicyanomethylnaphculene, 3-acetylamino-4-
Dissolve 4.70 g of nitroso-N,N-diethylaniline in 307 nl of acetonitrile, then dissolve 10 g of pyridine.
- was added thereto, and acetic anhydride 5- was added dropwise, followed by stirring at room temperature for 1 hour.

The reaction solution was poured into cold water and extracted with ethyl acetate. After washing the extract with water and drying, the solvent was distilled off under reduced pressure, a small amount of acetonitrile was added to the residue, and the precipitated crystals were collected by filtration. Recrystallization from ethyl acetate/n-hexane gave dark green crystals of infrared absorbing dye (4).

λmax 773 nm (chloroform) Other dyes of the present invention can also be synthesized by a similar method.

The thermal transfer dye-providing material of the present invention has, on a support, a thermal transfer layer containing at least a heat-transferable dye having near-infrared absorption represented by the above general formula (1), preferably together with a binder. .

This thermal transfer dye-providing material is prepared by preparing a coating solution by dissolving or dispersing the heat-transferable dye of general formula (1) and a conventionally known binder resin in a suitable solvent, and applying this to one side of the support. for example about 0.2 to 5 μ, preferably 0.4 to 2
It is obtained by applying and drying the coating amount to give a dry film thickness of μ to form a thermal transfer layer.

As the support for the thermal transfer dye-providing material of the present invention, any conventionally known support can be used. For example, polyethylene terephthalate; polyamide; polycarbonate; glassine paper; condenser paper; cellulose ester; fluoropolymer; polyether; polyacetal; polyolefin;
Examples include polyimide; polyphenylene sulfide; polypropylene; polysulfone; cellophane; and the like.

The thickness of the support of the thermal transfer dye-providing material is generally 2 to 30 mm.
μ. An undercoat layer may be provided if necessary. Further, a dye diffusion preventing layer made of a hydrophilic polymer may be provided between the support and the dye-donating layer. This further improves the transfer density. As the hydrophilic polymer, the water-soluble polymers described above can be used.

A slipping layer may also be provided to prevent the thermal head from sticking to the dye-donating material. This slipping layer is composed of lubricating substances, such as surfactants, solid or liquid lubricants or mixtures thereof, with or without polymeric binders.

Although the thermal transfer dye-providing material of the present invention can use the above-mentioned heat-transferable dye that absorbs in the near infrared rays alone, it is usually used together with yellow, magenta, and cyan image-forming dyes to produce full-color images. The system is used to form a In this case, the dye of the present invention can be used in the same dye-donating layer as any of the yellow, magenta, and cyan image-forming dyes, or can be provided as a dye-donating layer separate from these. Generally, in the dye of the present invention, the short wavelength absorption region often overlaps with the cyan region (600 to 700 nm), so it is advantageous for color reproduction to add the cyan dye to the dye-donating layer.

It is preferable to provide a mark for position detection at the same time as the formation of any of the dye-donating layers, since this eliminates the need for an ink or printing process separate from the formation of the dye-donating layer.

As the dye useful for forming a thermal transfer layer for providing a visible image, any dye conventionally used in thermal transfer dye-providing materials can be used, but in the present invention, particularly preferred dyes are about 150 to 800. It has a small molecular weight, and is selected in consideration of transfer temperature, hue, light resistance, solubility in ink and binder resin, dispersibility, etc.

Specifically, for example, disperse dyes, basic dyes, oil-soluble dyes, etc. can be mentioned, but in particular, Sumikaron Yellow E
4GL, Dianix Yellow H2G-FS, Miketone Polyeltel Yellow 3GSL, Kayasset Yellow 9
37, Sumikaron Red EFBL, Dianic Red ACE, Miketon Bolier Tell Red FB, Kayassetre, Do126, Miketon Fast Brilliant Blue B.

Kayaset Blue 136 or the like is preferably used.

Also, JP-A-60-27594, JP-A No. 59-78895
No. 60-53565, No. 60-159091,
Heat-transferable dyes described in Japanese Patent No. 62-294593, Japanese Patent No. 60-239289, etc. can be used.

Furthermore, as the binder resin used with the above dye, any binder resin conventionally known for this purpose can be used, and usually has high heat resistance and does not hinder the transfer of the dye when heated. things are selected. For example, polyamide resin, polyester resin,
Epoxy resins, polyurethane resins, polyacrylic resins (e.g. polymethyl methacrylate, polyacrylamide, polystyrene-2-acrylonitrile), vinyl resins including polyvinylpyrrolidone, polyvinyl chloride resins (e.g. vinyl chloride-vinyl acetate) copolymers), polycarbonate resins, polystyrene, polyphenylene oxide, cellulose resins (e.g. methylcellulose, ethylcellulose, carboxymethylcellulose, cellulose acetate hydrogen phthalate, cellulose acetate, cellulose acetate propionate, cellulose acetate butyrate, cellulose triacetate), polyvinyl Alcohol resins (e.g. partially saponified polyvinyl alcohols such as povinyl alcohol and polyvinyl butyral), petroleum resins, rosin ta'J, coumaron-indene resins, terpene resins, polyolefin resins (e.g. polyethylene, polypropylene), etc. used.

Such a binder resin is preferably used in a proportion of, for example, about 80 to 600 parts by weight per 100 parts by weight of the dye.

In the present invention, any conventionally known ink solvent can be freely used as the ink solvent for dissolving or dispersing the above pigment and binder resin.

A second embodiment of the thermal transfer dye-providing material is an embodiment in which the thermal transfer layer is a thermal melt transfer layer composed of an ink for forming a thermal transfer layer consisting of a wax containing a coloring agent such as a dye or a pigment. This ink is made by distributing and dispersing colorants such as carbon black and various dyes and pigments using waxes with appropriate melting points, such as paraffin wax, microcrystalline wax, carnauba wax, and urethane wax, as a binder. It is what it is. The ratio of the colorant and wax used is preferably such that the colorant accounts for about 10 to 65% by weight in the heat-melting transfer layer to be formed, and the thickness of the layer to be formed is about 1.5% by weight. A range of 5 to 6.0 μm is preferred. The production of the ink and its application onto the support can be carried out according to known techniques.

In order to prevent sticking due to the heat of the thermal head and improve slippage when printing from the back side of the dye-donating material, it is preferable to apply an anti-sticking treatment to the side of the support on which the dye-donating layer is not provided.

For example, it is preferable to provide a heat-resistant slip layer mainly consisting of (1) a reaction product of a polyvinyl butyral resin and an isocyanate, (2) an alkali metal salt or alkaline earth metal salt of a phosphoric acid ester, and (2) a filler. The polyvinyl butyral resin has a molecular weight of about 60,000 to 200,000, a glass transition point of 80 to 110''C, and a vinyl butyral resin with a vinyl butyral portion of 15 to 40% by weight from the viewpoint of having many reaction sites with isocyanate. As the alkali metal salt or alkaline earth metal salt of phosphoric acid ester, Gafac RD720 manufactured by Toho Chemical Co., Ltd. is used, and it is about 1 to 50% by weight, preferably about 10 to 40% by weight based on the polyvinyl butyral resin. Good to use.

It is desirable that the heat-resistant slip layer has heat resistance as the lower layer.
A combination of a synthetic resin that can be cured by heating and its curing agent,
For example, a combination of polyvinyl butyral and polyvalent isocyanate, acrylic polyol and polyvalent isocyanate, cellulose acetate and a titanium chelating agent, or polyester and an organic titanium compound may be provided by coating.

The dye-donor element may also be provided with a hydrophilic barrier layer to prevent diffusion of the dye towards the support. Hydrophilic dye barrier layers contain hydrophilic materials useful for their intended purpose. Generally excellent results are obtained with gelatin, poly(acrylamide), poly(isopropylacrylamide)
, butyl methacrylate grafted gelatin, ethyl methacrylate grafted gelatin, cellulose monoacetate, methylcellulose, poly(vinyl alcohol), poly(ethyleneimine), poly(acrylic acid), poly(vinyl alcohol) and poly(vinyl acetate) It is obtained by using a mixture, a mixture of poly(vinyl alcohol) and poly(acrylic acid) or a mixture of cellulose monoacetate and poly(acrylic acid). Particularly preferred are poly(acrylic acid), cellulose monoacetate or poly(vinyl alcohol).

The dye-providing material may be provided with a subbing layer. In the present invention, any undercoat layer may be used as long as it has the desired effect, but a preferred specific example is (acrylonitrile-vinylidene chloride-acrylic acid) copolymer (weight ratio 14:80:6).
), (butyl acrylate-2-aminoethyl methacrylate-2-hydroxyethyl methacrylate) copolymer (weight ratio 30:20:50), linear/saturated polyester such as Bostik 7650 (Emhart, Bostic) stick chemical group) or chlorinated high density poly(ethylene-trichloroethylene) resins.

There is no particular limit to the amount of undercoat layer applied, but it is usually 0.1
~2.0 g/m''.

In the present invention, a thermal transfer dye-providing material is superimposed on a thermal transfer image-receiving material, and thermal energy is applied according to image information from either side, preferably from the back side of the thermal transfer dye-providing material, using a heating means such as a thermal head. Thereby, the dye in the dye-donating layer can be transferred to the thermal transfer image-receiving material depending on the magnitude of heating energy, and a color image with excellent clarity and resolution and gradation can be obtained.

The heating means is not limited to a thermal head, and known means such as a laser beam (for example, a semiconductor laser), an infrared flash, a thermal pen, etc. can be used.

In the present invention, by combining the thermal transfer dye-providing material with the thermal transfer image-receiving material, images can be printed by printing using various thermal printing printers, by facsimile, or by magnetic recording, magneto-optical recording, optical recording, etc. It can be used to create prints from , television, and CRT screens.

For details on the thermal transfer recording method, see Japanese Patent Application Laid-Open No. 60-348.
You can refer to the description in No. 95.

The thermal transfer image-receiving material used in combination with the thermal transfer dye-providing material of the present invention basically has an image-receiving layer for receiving a heat-transferable dye on a support. Any support can be used as long as it can withstand the transfer temperature and satisfies the requirements in terms of smoothness, whiteness, slipperiness, friction, antistatic properties, and denting after transfer. For example, synthetic paper (polyolefin-based, polystyrene-based, etc. synthetic paper), fine paper, art paper, coated paper, cast coated paper, wallpaper, backing paper, synthetic resin or emulsion impregnated paper, synthetic rubber latex impregnated paper, synthetic resin Paper supports such as paperboard, paperboard, cellulose fiber paper, polyolefin coated paper (especially paper coated on both sides with polyethylene), various plastic films or sheets such as polyolefin, polyvinyl chloride, polyethylene terephthalate, polystyrene, methacrylate, polycarbonate, etc. A film or sheet treated to give the plastic a white reflective property, and a laminate made of any combination of the above may also be used.

The thermal transfer image-receiving material is provided with an image-receiving layer. This image-receiving layer receives the heat-transferable dye that migrates from the heat-transferable dye-providing material during printing, and is made of a material capable of receiving the heat-transferable dye that has the function of dyeing the heat-transferable dye. Alone or together with other binder materials, the thickness 0.
It is preferable that the film has a thickness of about 5 to 50 μm. Typical examples of polymers that can accept heat-transferable dyes include the following resins.

(a) Dicarboxylic acid components having ester bonds such as terephthalic acid, isophthalic acid, and succinic acid (these dicarboxylic acid components contain sulfonic groups,
Polyester resins obtained by condensation of ethylene glycol, diethylene glycol, propylene glycol, neopentyl glycol, bisphenol A, etc. with carboxyl groups (which may be substituted with carboxyl groups, etc.): polymethyl methacrylate, polybutyl acrylate, polymethyl acrylate, polybutyl Polyacrylic acid ester resin or polymethacrylic acid ester resin such as acrylate: Polycarbonate resin: Polyvinyl acetate resin: Styrene acrylate resin: Vinyl toluene acrylate resin, etc. Specifically, JP-A-59-101395 and JP-A No. 6
No. 3-7971, No. 63-7972, No. 63-797
No. 3 and No. 60-294862. In addition, commercially available products include Toyobo's Byron 290, Byron 200, Byron 280, and Byron 3.
00, Byron 1O3, Byron GK-140, Byron GK-130, Kao ATR-2009, ATR-
2010 etc. can be used.

(b) Those with urethane bonds polyurethane resin, etc.

(c) Those with an amide bond such as boryamide resin.

(d) Those with urea bonds urea resin etc.

(e) Those with a sulfon bond.

polysulfone resin, etc.

(f) Others having highly polar bonds, such as polycaprolactone resin, styrene-maleic anhydride resin, polyvinyl chloride resin, polyacrylonitrile resin, etc.

In addition to the synthetic resins mentioned above, mixtures or copolymers thereof can also be used.

The thermal transfer image-receiving material, particularly the image-receiving layer, may contain a high-boiling organic solvent or a thermal solvent as a substance capable of receiving heat-transferable dyes or as a dye diffusion aid.

Specific examples of high boiling point organic solvents and thermal solvents include JP-A No. 6
No. 2-174754, No. 62-245253, No. 61
-209444, 61-200538, 62-
No. 8145, No. 62-9348, No. 62-30247
No. 62-136646.

The image receiving layer may be composed of two or more layers. In that case, the layer closer to the support should be made of a synthetic resin with a low glass transition point, or a high boiling point organic solvent or hot solvent should be used to increase dye dyeing properties, and the outermost layer should have a glass transition point. By using a synthetic resin with a higher point, or by minimizing or not using high-boiling point organic solvents or hot solvents, you can prevent stickiness on the surface, adhesion with other ′+yJ materials, and transfer to other materials after transfer. It is desirable to have a structure that prevents failures such as retransfer of the dye and blocking with the thermal transfer dye-providing material.

The total thickness of the image-receiving layer is 0.5 to 50 pm, especially 3 to 3 pm.
A range of 0 μm is preferred. In the case of a two-layer configuration, the outermost layer is 0.
It is preferably in the range of 1 to 2 μm, particularly 0.2 to 1 μm.

The thermal transfer image-receiving material of the present invention may have an intermediate layer between the support and the image-receiving layer.

The intermediate layer can be a cushion layer, a porous layer, or a
This layer has one of the functions of a dye diffusion prevention layer or a layer having two or more of these functions, and in some cases also serves as an adhesive.

The dye diffusion-preventing layer plays a role, in particular, in preventing the heat-transferable dye from diffusing into the support. As the binder constituting this diffusion prevention layer, 1. The binder may be water-soluble or organic solvent-soluble, but a water-soluble binder is preferred, and an example thereof is the water-soluble binder mentioned above as the binder for the image-receiving layer, particularly gelatin.

The porous layer is a layer that prevents the heat applied during thermal transfer from diffusing from the image-receiving layer to the support and effectively utilizes the applied heat.

The image receiving layer, cushion layer, porous layer, diffusion prevention layer, adhesive layer, backing layer, etc. that constitute the thermal transfer image receiving material of the present invention include silica, clay, talc, diatomaceous earth, calcium carbonate, calcium sulfate, barium sulfate, silica, etc. Fine powders of acid aluminum, platform zeolite, zinc oxide, lithopone, titanium oxide, alumina, etc. may be included.

A fluorescent brightener may be used in the thermal transfer image-receiving material.

Examples include K, Veenkataramanli
rThe Chemis-try of 5ynth
etic DyesJ Volume 8 Chapter 8, JP-A-61-14
Examples include compounds described in No. 3752 and the like. More specifically, stilbene compounds, coumarin compounds, biphenyl compounds, hendioxazolyl compounds, naphthalide compounds, pyrazoline compounds, carbostyril compounds, 2,5-dihenzooxazolethiophene compounds Examples include.

Optical brighteners can be used in combination with antifade agents.

In the present invention, in order to improve the releasability of the thermal transfer dye-providing material and the thermal transfer image-receiving material, the dye-providing material and/or
Alternatively, it is preferable to include a release agent in the layers constituting the image-receiving material, particularly preferably in the outermost layer corresponding to the surface where both materials come into contact.

Examples of mold release agents include solid or waxy substances such as polyethylene wax, amide wax, and Teflon powder, surfactant fJ such as difluorine-based and phosphate ester-based oils, and conventionally known oils such as paraffin-based, silicone-based, and fluorine-based oils. Although any of the above mold release agents can be used, silicone oil is particularly preferred.

As the silicone oil, in addition to unmodified silicone oil, modified silicone oils such as carboxy-modified, amino-modified, and epoxy-modified silicone oils can be used.

Examples include various modified silicone oils described on pages 6 to 18B of "Modified Silicone Oil J Technical Data" published by Shin-Etsu Silicone Co., Ltd. When used in an organic solvent-based binder, this binder When an atomically modified silicone oil having a group that can react with a crosslinking agent (for example, a group that can react with an isocyanate) is emulsified and dispersed in a water-soluble binder, carboxy-modified silicone oil (for example, a group that can react with an isocyanate) is used. Co., Ltd. (trade name: X-22-3710) is effective.

The layers constituting the thermal transfer dye-providing material and the thermal transfer image-receiving material used in the present invention may be hardened with a hardening agent.

When curing organic solvent-based polymers, JP-A-61
Hardeners described in Japanese Patent No. 199997 and No. 58-215398 can be used. For polyester resins, it is particularly preferable to use incyanate-based hardeners.

For curing water-soluble polymers, U.S. Patent No. 4,678.7
No. 39, column 41, JP-A-59-116655, JP-A No. 62
Hardeners described in Japanese Patent Nos. 245261 and 61-18942 are suitable for use.

More specifically, aldehyde hardeners (formaldehyde, etc.), aziridine hardeners, epoxy hardeners, etc.), vinyl sulfone hardeners (N,N'-ethylene-bis(vinylsulfonylacetate, etc.) mido)ethane, etc.),
Examples include N-methylol hardeners (dimethylol urea, etc.) and polymer hardeners (compounds described in JP-A-62-234157, etc.).

Antifading agents may be used in the thermal transfer dye-providing material and the thermal transfer image-receiving material. Antifading agents include, for example, antioxidants, ultraviolet absorbers, or certain metal complexes.

Examples of antioxidants include chroman compounds, coumaran compounds, phenol compounds (for example, hindered phenols), hydroquinone derivatives, hindered amine derivatives, and spiroindane compounds. Compounds described in JP-A-61-159644 are also effective.

Benzotriazole compounds (
U.S. Patent No. 3,533,794, etc.), 4-thiazolidone compounds (U.S. Patent No. 3,352,681, etc.),
Benzophenone compounds (JP-A-56-2784, etc.), other JP-A-54-48535, JP-A-62-136
There are compounds described in No. 641, No. 61-88256, and the like. Further, the ultraviolet absorbing polymer described in JP-A No. 62-260152 is also effective.

As metal complexes, US Pat. No. 4,241,155,
No. 4,245,018, columns 3 to 36, No. 4,25
No. 4,195, columns 3 to 8, JP-A-62174741,
No. 61-88256, pages (27) to (29), patent application No. 61-88256
No. 2-234103, No. 62-31096, patent application No. 62-31096
There are compounds described in No. 2-230596 and the like.

Examples of useful anti-fading agents are disclosed in JP-A No. 62-215272 (
125) to (137).

The anti-fading agent for preventing fading of the dye transferred to the image-receiving material may be included in the image-receiving material in advance, or it may be supplied to the image-receiving material from the outside by a method such as transfer from a dye-donating material. You can.

The above antioxidants, ultraviolet absorbers, and metal complexes may be used in combination.

Various surfactants can be used in the constituent layers of the thermal transfer dye-providing material and the thermal transfer image-receiving material for the purposes of coating aids, improving peelability, improving slipperiness, preventing electrification, accelerating development, and the like.

Nonionic surfactants, anionic surfactants.

Amphoteric surfactants and cationic surfactants can be used. Specific examples of these are JP-A-62-173463,
It is described in No. 62-183457 and the like.

In addition, when dispersing substances that can accept heat-transferable dyes, mold release agents, anti-fading agents, ultraviolet absorbers, optical brighteners, and other hydrophobic compounds in a water-soluble binder, the interface is used as a dispersion aid. Preferably, an activator is used. For this purpose, in addition to the above-mentioned surfactants, JP-A-59-15763
The surfactants described in Sections 37 and 38 of No. 6 are particularly preferably used.

The constituent layers of the thermal transfer dye-providing material and the thermal transfer image-receiving material may contain an organic fluoro compound for the purpose of improving slipperiness, preventing static electricity, improving releasability, and the like. Representative examples of organic fluoro compounds include Japanese Patent Publication No. 57-9053, columns 8 to 17;
Fluorine surfactants described in JP-A-61-20944 and JP-A-62-135826, or oily fluorine compounds such as fluorine oil, or solid fluorine compound resins such as tetrafluoroethylene resin, etc. Examples include hydrophobic fluorine compounds.

A matting agent can be used in the thermal transfer dye-providing material and the thermal transfer image-receiving material. As a matting agent, silicon dioxide, polyolefin, polymethacrylate, etc.
In addition to the compounds described in No. 1-8825e (page 29), Japanese Patent Application No. 110064/1982, such as benzoguanamine resin beads, polycarbonate resin beads, and AS resin beads,
There is a compound described in No. 62-110065.

(Effects of the Invention) According to the present invention, since the infrared light-absorbing heat-transferable dye represented by the general formula [I] is used, thermal transfer provides a color image that can be read by an infrared prereader. Recording materials can be obtained.

(Specific Examples of the Invention) Hereinafter, specific examples of the present invention will be shown, and the effects of the present invention will be explained in further detail.

Example 1 (a) Coating liquid for dye-donor layer A mixture having the above composition was treated with an ultra disperser for 30 minutes to prepare a coating liquid for dye-donor layer of a thermal transfer dye-donor material.

(b) Preparation of thermal transfer dye-providing material The above coating solution was applied onto a polyethylene terephthalate film (7 μm thick) using a wire bar #40, and then air-dried to prepare a transfer sheet.

(C) Transfer recording and evaluation The dye-donating layer surface of the above thermal transfer dye-donating material was coated with synthetic paper (thickness 150 μm) whose surface was coated with polyester resin.
recording was carried out by heating the thermal transfer dye-providing material from the back side using a thermal head under the following conditions. 800r++ by reflection densitometer for pale green image obtained on thermal transfer image-receiving material
The reflection density at n was measured. A reading test was also conducted using an optical character reader H3-OCR manufactured by Sumitomo Electric, and the success rate was measured.

Recording conditions Thermal head output 0.25W/dot pulse width
: 0. 15~15m sec dot density
: 6 dots/III + Comparative Example A thermal transfer dye-providing material was prepared in the same manner as in Example 1 by using the following cyan image-forming dye (C-1) instead of the infrared light-absorbing dye (2) of the present invention. , transcription records were performed and evaluated.

The above evaluation results are shown in the table below.

By using the infrared light absorbing dye of the present invention, OCR
It can be seen that reading aptitude can be imparted.

Example 2 Same as Example 1 except that the dyes (3), (4), (5), (6), and (8) of the present invention were used in place of the dye (2) of the present invention used in Example 1. A coating solution was prepared, a thermal transfer dye-providing material was prepared, transfer recording was performed, and evaluation was performed using the method described above, and the results shown in the table below were obtained. It can be seen that both cases have sufficient reflection density at 800 nm and are suitable for OCR reading.

Example 3 The following yellow, magenta,
Coating solutions of cyan and infrared light-absorbing dyes were prepared to produce thermal transfer dye-providing materials.

Yellow dye (Y): Magenta dye (M): Infrared light absorbing dye (IR) Two dyes of the present invention (2) The above thermal transfer dye-providing materials are sequentially transferred and recorded in the same character image pattern, A black character image was obtained. An OCR reading test was conducted on the obtained character images.

On the other hand, for comparison purposes, similar transfer recording was performed using transfer sheets of three other colors except for the infrared light-absorbing dye transfer sheet of the present invention, black character images were obtained, and an OCR reading test was conducted. The results are shown in the table below, and it can be seen that perfect OCR readability can be imparted by using the dye of the present invention.

Claims (1)

[Scope of Claims] A thermal transfer dye-providing material comprising at least a heat transferable dye represented by the following general formula [I] on a support. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [I] In the above formula, R_1 is a halogen atom, an alkoxy group, an aryloxy group, an acylamino group, an alkoxycarbonylamino group, a sulfonylamino group, a sulfamoyl group, a hydroxyl group, a sulfonyl group, and represents a ureido group,
n represents an integer from 0 to 3, and when n is 2 or 3, R_
1 may be the same or different. R_2 and R_3
may be the same or different and represent a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, an acylamino group, an alkoxycarbonylamino group and a ureido group,
R_4 and R_5 may be the same or different and represent a hydrogen atom, an alkyl group or an aryl group. R_4
and R_5 may be bonded to each other to form a ring. Also,
R_4 and R_5 may be combined with a benzene ring to form a 5- or 6-membered nitrogen-containing heterocycle. X represents a cyano group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, or a sulfonyl group. The above substituents may be further substituted with other substituents.