JPS60190389A - Sheet for heat transfer color recording - Google Patents

Abstract

PURPOSE:To provide the titled sheet for transfer recording which enables the presentation of contrast in the recording according to the level of heating energy by arranging a water dispersing ink containing a binder made of a water soluble or water dispersing resin and a non-ionic sublimating pigment and a substrate. CONSTITUTION:A water soluble or water dispersing polyester resin produced by copolymerization of ester forming compounds having a sulfonic group, such as sulfonic isophthalate or a water soluble or water dispersing acrylic resin containing a vinyl monomer component having a hydrophilic group such as maleic acid or a mixture thereof as binder and a non-ionic sublimating pigment such as azo and nitro-based ones are mixed preferably at the ratio of 1-20wt% to obtain a water dispersing ink. Then, the ink thus obtained is applied on a substrate made up of a thin sheet paper such as glassine made water resistant and a polyester film by gravure coating or the like in such a manner as to be thick preferably 0.01-5mum after drying to obtain the desired sheet.

Description

[Detailed description of the invention] The present invention relates to a color thermal transfer recording sheet.

In OA terminals such as facsimile machines, printers, and copying machines, which are rapidly becoming popular in recent years, there is a growing demand for color recording that contains a large amount of information and is visually easy to read.

Furthermore, it is desired to develop a technology for color recording 10,000 television images.

Currently, color recording techniques using electrophotography, inkjet printing, thermal transfer recording methods, etc. are being considered for these purposes.

Among these, the thermal transfer recording method is considered to be an advantageous method compared to other methods because the device is easy to maintain and operate, and the device and consumables are inexpensive.

In the thermal transfer recording method, the ink-coated surface of a sheet-like substrate coated with ink containing five dyes is superimposed on the recording medium.
The back of the ink-applied surface of the substrate is heated with a thermal head,
Thermal transfer method is a method in which recording is performed by transferring the dye on the substrate to the recording material.Thermal transfer method uses a recording sheet C (hereinafter referred to as sheet) coated with heat-melting ink on the substrate, and the sublimation method. There is a sublimation transfer method that uses a sheet IY coated with ink containing a pigment.With the sublimation transfer method, the amount of sublimation transfer of the pigment can be controlled by adjusting the energy given to the thermal head, making it easy to express one gradation. This is particularly advantageous for full color recording.

Inks used for ordinary recording include solvent inks using organic solvents as a medium and water-based inks using water or a mixture of water and a water-soluble organic solvent as a medium.

Solvent ink has been used as an ink for creating thermal transfer recording sheets using a sublimation transfer method.

However, in the case of the solvent ink, the sublimable dye is dissolved in the organic solvent, so when the ink is applied to the substrate and dried, the dye dissolved in the ink recrystallizes and precipitates on the substrate. Therefore, unevenness occurs in the dye distribution on the sheet, and when such a sheet is used, there is a problem in that transfer recording also becomes uneven and the image quality deteriorates. My father, many organic solvents are generally toxic and flammable, making them difficult to handle from a health and safety standpoint.

Water-based ink Z conventionally used for recording, when used as an ink for producing sheeters for heat-sensitive transfer recording, the substrate, especially mechanical strength 2 abrasion resistance, dimensional stability, heat resistance, water resistance With polyester film, which has excellent properties and is also inexpensive and widely used! , the compatibility is low, and the adhesion between the ink and the substrate is not necessarily sufficient. Therefore, during thermal transfer, if heat above a certain level is applied, one dye is transferred together with the binder, and the amount of sublimation transfer that corresponds to the size of the heating energy is not transferred, resulting in a poor impression when using sublimable dyes. There was a problem that it was difficult to express gradation, which is a characteristic of thermal transfer recording sheets.The present invention solves the problem by coating a substrate with an aqueous dispersion ink consisting of a sublimable dye and a special binder. It is an object of the present invention to provide a heat-sensitive transfer recording sheet that enables recording gradation expression depending on the magnitude of energy.

That is, the gist of the present invention is a color thermal transfer recording sheet comprising a substrate and an aqueous dispersion ink containing a nonionic sublimable dye and a binder.

Substrates in the present invention include capacitor paper, thin paper such as glassine paper, polyester-based, polyamide-based,
Examples include polyimide-based, cellulose-based, acrylic-based and vinyl-based resin films. Preferably, a polyester resin film is used, and a coaxially stretched polyethylene terephthalate film is particularly preferably used.

In addition, when a resin film is used as the substrate, a heat-resistant protective film made of silicone resin, epoxy resin, melamine resin, phenol resin, fluororesin, polyimide resin, etc. may be provided on the back side of the ink-coated surface of the film, if necessary. The ink-coated surface may be subjected to heat-resistant processing, or the surface coated with the ink may be coated with an anchor coat to improve adhesion. When using thin paper as a base, the ink-coated surface of the thin paper can be treated to make it waterproof, if necessary.

Examples of the binder include water-soluble or water-dispersible polyester resins, water-soluble or water-dispersible acrylic resins, or mixtures thereof.

Water-soluble or water-dispersible polyester resins include:
Japanese Patent Publication No. Sho II'7-47-41O, Japanese Patent Publication No. Sho 10-4
A polyester resin having a sulfonic acid group described in Publication No. 3'19'1 etc. or a polyester resin similar thereto, and a glycol component are condensed together with a compound having an ester-forming sulfonic acid group. This can be obtained by

Examples of the dicarboxylic acid component include terephthalic acid, isophthalic acid, 2. ! ;-Aromatic dicarboxylic acids such as naphthalene dicarboxylic acid, or ester-forming derivatives of the aromatic dicarboxylic acids, aliphatic dicarboxylic acids such as adipic acid, azelaic acid, sebacic acid, or ester-forming derivatives of the aliphatic dicarboxylic acids; , oxymonocarboxylic acids such as oxybenzoic acid, and ester-forming derivatives of the oxymonocarboxylic acids.

Glycol components include ethylene glycol, /, 4
Aliphatic, alicyclic and aromatic diols such as 1-butanediol, diethylene glycol, triethylene glycol, /, cucyclohexane dimetatool, p-xylene diol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, etc. I can do it.

Examples of compounds having an ester-forming sulfonic acid group include sulfoisophthalic acid, sulfoterephthalic acid, ll-
Mention may be made of metal salts of sulfonaphthalene, 7-dicarboxylic acids and ester-forming derivatives thereof.

Further, the above polyester resin can be obtained by sulfonating the unsaturated group of a polyester containing an ester-forming aliphatic unsaturated compound as a copolymerization component with a sulfonating agent such as sodium bisulfite or sodium metabisulfite. can.

In addition to ester resins, polyester resins made of compounds having trivalent or higher ester-forming components or polyester resins having reactive unsaturated groups can also be used.

7-7 Examples of the acrylic resin in the present invention include those containing alkyl acrylate or alkyl methacrylate as a main polymerization component.

Preferably, a water-soluble or water-dispersible vinyl monomer component that is copolymerizable with the polymerization component and has a functional group such as a reactive functional group, a self-crosslinking functional group, or a hydrophilic group. acrylic resin.

The alkyl groups of the above alkyl acrylates and alkyl methacrylates include methi/14, ethyl group, n-
Propyl group, isopropyl group.

n-butyl group, isobutyl group, t-butyl group.

-monoethylhexyl group, lauryl group, stearyl group, cyclohexyl group, etc.

The vinyl monomer has functions such as imparting hydrophilicity to the resin, or imparting adhesiveness and affinity to the polyester film.

Preferred functional groups in the vinyl monomer include a carboxyl group or a salt thereof, an acid anhydride group thereof, a sulfonic acid group or a salt thereof, an amide group or an alkylolated amide group, an amino group [substituted amine [containing groups] or alkylolated amine groups or salts thereof, hydroxyl groups, epoxy groups, etc., and particularly preferred are carboxyl groups or salts thereof.

Examples include acid anhydride groups and epoxy groups, and one or more of these groups may be contained in the resin.

Examples of the vinyl monomer include the following compounds.

Examples of compounds having a carboxyl group, a salt thereof, or an anhydride group thereof include acrylic acid, methacrylic acid,
Examples include itaconic acid, maleic acid, fumaric acid, crotonic acid, metal salts and ammonium salts of these carboxylic acids, and maleic anhydride.

Examples of compounds having a sulfonic acid group or a salt thereof include vinyl sulfonic acid, styrene sulfonic acid, metal salts and ammonium salts of these sulfonic acids; examples of compounds having an amide group or an alkylolated amide group include: Acrylamide.

Methacrylamide, N-methylmethacrylamide, methylolated acrylamide, methylolated methacrylamide, ureido vinyl ether, β-ureido isobutyl vinyl ether.

Examples include ureidoethyl acrylate.

Examples of compounds having an amino group or an alkylolated amine group or a salt thereof include diethylaminoethyl vinyl ether, co-aminoethyl vinyl ether, 3-aminopropyl vinyl ether, 2-aminobutyl vinyl ether, dimethylaminoethyl methacrylate, and dimethylaminoethyl vinyl ether. .

Examples include those in which the amino group is methylolated or double-chlorinated.

Examples of compounds having a hydroxyl group include β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate,
β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, β-hydroxyethyl vinyl ether, 3-hydroxypentyl vinyl ether,
Examples include 6-hydroxyhexyl vinyl ether, polyethylene glycol monoacrylate, polyethylene glycol monomethacrylate, polypropylene glycol monoacrylate, and polypropylene glycol monomethacrylate.

Examples of the compound having an epoxy group include glycidyl acrylate and glycidyl methacrylate.

Furthermore, the following compounds may be used in combination in addition to the above.

That is, acrylonitrile, methacrylonitrile, styrenes, butyl vinyl ether, mono- or dialkyl maleate 1,<fA/, mono- or dialkyl itaconate, methyl vinyl ketone,
Examples include vinyl chloride, vinylidene chloride, vinyl acetate, vinylpyridine, vinylpyro=11-p\'1, lydone, and vinyltrimethoxysilane.

Aqueous dispersion inks are obtained by mixing sublimable dyes in an aqueous medium.

f. sublimable dye in the presence or absence of a dispersant,
It can also be obtained by directly finely dispersing a water-soluble or water-dispersible resin in an aqueous solution using a dispersion machine.

The water-based dispersion ink may contain a water-soluble organic solvent in 1% of the base material in order to improve the coating properties on polyester film and the drying properties of the ink. It may be added during dispersion or after the dye is finely dispersed. As these organic solvents, alcohols are particularly preferred, and specific examples include methanol, ethanol, globanol, methyl cellosolve, ethyl cellosolve, flovirce 12-losolve, and the like.

As the dispersant, anionic, cationic, and nonionic dispersants used in disperse dyes can be used, specifically.

Sulfuric acid esters of higher alcohols, alkylbenzene sulfonates, alkylnaphthalene sulfo 7r1M salts, condensates of 7-talene sulfonic acid and toformaldehyde, organic polyamines, polyoxyethylene alkylphenol ethers.

Polyoxyethylene higher alcohol ether.

Alkylphenol polyglycol ether.

Examples include quaternary flucol polyglycol ether.

In addition, as sublimable dyes, nonionic dyes that are generally used for transfer printing of textiles can be used, but in terms of chemical structure, they include azo, anthraquinoy, nitro, styryl, naphthoquinone, and quinophthalones. Examples include pigments such as azomethine-based, azomethine-based, coumarin-based, and integrated polycyclic threads.

In addition to the above, the water-based dispersion ink may contain anti-blocking agents, anti-foaming agents, inorganic fine particles, antioxidants,
It can contain ultraviolet absorbers, antistatic agents, and the like. Furthermore, water-soluble or water-dispersible resins such as gelatin, polyvinyl alcohol, silicone resins, epoxy resins, vinyl resins, etc. can be contained as needed. It is also possible to add and use a crosslinking agent such as.

In the above water-based dispersion ink, the concentration of sublimable dye is /
The concentration of the water-soluble or water-dispersible resin is in the range of S-41% by weight based on solid content, and the concentration of the dispersant is in the range of O-500% by weight based on the dye. A range of weight it% may be mentioned.

As a method for applying a water-based dispersion ink to a polyester film, for example, Yuji Harasaki's ``Coating Method J (
1979) can be carried out using a reverse roll coater, a gravure coater, a rod coater, an air doctor coater, etc. shown in Maki Shoten, but a wire bar etc. can also be used as a trial method.

The thickness of the ink coating layer on the polyester film after drying is suitably in the range of θ, oiμ to Sμ.

Using the color thermal transfer recording sheet of the present invention.

Recording is carried out by overlapping the ink-coated surface of the sheet with the object to be recorded, and heating the ink-coated surface of the sheet from the back side with a thermal head that generates heat based on electrical signals from image information. However, plain paper can be used as the recording medium.

In addition, the above-mentioned recording medium may be plain paper coated or impregnated with a resin having good compatibility with one dye, and in some cases with inorganic fine particles such as silica gel, or laminated with a resin film, or acetylated. By using special processed paper such as treated paper.

It is possible to obtain good records with excellent color development and various fastness properties of the dye. In addition to the above-mentioned plain paper and special processed paper, films of various resins or synthetic papers made from them can also be used.

Furthermore, after the transfer recording, for example, a polyester film can be heat-pressed and laminated on the transfer recording surface to improve the color development of the dye and to stabilize the recording during storage.

In the aqueous dispersion ink of the present invention, since the sublimable dye used is nonionic, the dye stably exists in a finely dispersed state in the aqueous medium. Even after drying, a sheet in which one dye is uniformly dispersed on the substrate can be obtained without the dye recrystallizing or precipitating on the substrate.

Further, the binder in the aqueous dispersion ink has a strong coating film and good heat resistance, so that the binder does not fuse to the recording medium during transfer recording.

EXAMPLES The present invention will be specifically explained below with reference to Examples, but these Examples are not intended to limit the present invention.

Example 1 16-a) Preparation of aqueous dispersion ink Sublimable dye O0, Disperse blue ivy/Ogk
A polyethylene glycol phenol ether dispersant, Nucol 71O (manufactured by Nippon Nyukazai Co., Ltd., trade name), was added to QOml of water, and the mixture was treated with a sand grind mill to be finely dispersed. This fine dispersion liquid and aqueous saturated polyester resin ;OgC binder]
By mixing these, an aqueous dispersion ink in which the pigment was stably dispersed was prepared.

b. Creation of Sheet Sheet 7 was prepared in the following manner using, as a substrate, a biaxially stretched polyethylene terephthalate film (thickness: 2 μm) whose back surface on which the ink was applied was heat-resistant treated with polyimide resin.

That is, the aqueous dispersion ink #a) above was applied onto a substrate using a bar coater and dried to obtain a sheet.

The obtained sheet has good hardness, and the aqueous dispersion ink of a) above firmly adheres to the substrate.

It also had a coating film in which the pigment was uniformly dispersed.

C) Method for making image-receiving paper Water-based polyester resin MD-/CoOO (solid content, ?lI
#, prepared by mixing 1 g of silica N1 psil Ft Coco (7A (manufactured by Nippon Silikani Gyo Co., Ltd., trade name)) / (manufactured by Yobo Seki Co., Ltd., trade name) / (manufactured by Nippon Silikani Gyo Co., Ltd., trade name), was mixed with high-quality paper (thickness: 5 pieces). 00 μm) using a bar coater.

d] Transfer recording test and results Using the sheet and image receiving paper described above, electric power of θ, AW/dot was applied for the time shown in Table 1 using a thermal head with a heating resistor density of 1 gdot/dot, and recording was performed. I did this.

The sheet and the image-receiving paper were not fused during recording, and the binder of the sheet was not transferred to the image-receiving paper, and the sheet and the image-receiving paper could be easily separated after recording.

In addition, the obtained records have good resolution of each dot,
Shows a clear cyan color, and.

As shown in Table 7, the color density increased with application time.

The color density was measured using a densitometer R manufactured by Macbeth Co., Ltd. in the United States.
It was measured using D-5111 type (filter: RATSUTENEN 2) and calculated using the following formula.

Color fIkK = 10gto (Product o/I) Process 0: Intensity of light reflected from the standard white reflector Work: Intensity of reflected light from the test object The color density in the following examples was determined using the same method. Ta.

Example a) Preparation of water-based dispersion ink Instead of the water-based saturated polyester resin of Example 1 as a binder, water-based acrylic resin A-i0Q (solid content 1) was used as the binder.
An aqueous dispersion ink in which one dye is stably dispersed was prepared according to the method of Example 1 using Io weight section, Toagosei 19- Chemical Industry Co., Ltd., product name). Preparation of bJ sheet. A sheet was obtained according to the method of Example 1 using a dispersing machine.

The obtained sheet had good hardness, and the aqueous dispersion ink of above a) adhered firmly to the substrate.

It had a coating film in which one dye was uniformly dispersed.

C) Method of making image receiving paper An image receiving boat was made according to the method of Example 1. d) Transfer recording test and results Using the above sheet and receiving paper, recording was carried out according to the method of Example 1. The sheet and the image-receiving paper were not fused together during recording, and the binder of the sheet was not transferred to the image-receiving paper, and the recorder could easily separate the sheet and the image-receiving paper. The resulting recording showed good resolution of each dot and a clear cyan color, and the color density increased as the application time increased as shown in Table 1.

Example J a) Preparation of water-based dispersion ink Water-based saturated polyester resin XWR-90 of Example 1 and water-based acrylic resin A- of Example 1 as binders
An aqueous dispersion ink in which the dye was stably dispersed was prepared according to the method of Example 1 using 25 g of each of Qll.

bJ Preparation of Sheet A sheet was prepared using the aqueous dispersion ink described above and according to the method in Examples.

The obtained sheet has good hardness, and the aqueous dispersion in a) above adheres firmly to the substrate.

It also had a coating film in which the pigment was uniformly dispersed.

C) How to make receiver paper Receiving paper was prepared according to the method in Example/.

d) Transfer recording test and results Using the above sheet and image receiving paper, recording was performed according to the method of Example 1. As a result, the sheet and the image receiving paper were not fused during recording, and the binder of the sheet was not bonded to the image receiving paper. After recording, the sheet, image-receiving paper, and Z could be easily separated without any transition.

In addition, the obtained recording had good resolution of each dot and exhibited a clear cyan color, and the color density increased as the application time increased as shown in Table 2.

Example y Preparation of water-based dispersion ink C0 process and Disper Red 60 were used as sublimable pigments, and water-based acrylic resin A-
EXAMPLE 1 An aqueous dispersion ink in which one dye was stably dispersed was prepared according to the method of Example/, except that /Qll was used.

b) Preparation of sheet Example 1 except that the aqueous dispersion ink of the above gradient was used and a polyimide film (thickness 1 μm) was used as the substrate.
I got the sheet according to the method.

The obtained sheet had good hardness, and the water-based dispersion ink of aJ described above adhered firmly to the substrate.

It also had a coating film in which the pigment was uniformly dispersed.

C) How to make receiver paper Receiving paper was prepared according to the method in Example/.

d) Transfer recording test and results When recording was carried out according to the method of Example 1 using the above sheet and image-receiving paper, the sheet and image-receiving paper were not fused during recording. /< Ingu did not transfer to the image-receiving paper (the sheet and image-receiving paper could be easily separated after recording.

The resulting record showed good resolution of each dot and a clear 1-zenta color, and the color density increased with the application time as shown in Table 1.

However, the measurement of the density of one color was carried out using the same equipment as in Example 1, but a 7165 g latte was used as the filter.

Example 3 Preparation of water-based dispersion ink Sublimable pigments: C1, Solvent Yellow//II
The dye was stably dispersed according to the method of Example 1, except that the aqueous saturated polyester resin A water-based dispersion ink was prepared.

b) Preparation of Sheet A sheet was obtained according to the method in Example 1, except that the aqueous dispersion ink of a) above was used and condenser paper (thickness 10 μII) J'f was used as the substrate.

The obtained sheet had good hardness, the aqueous dispersion ink of a) above firmly adhered to the substrate, and a coating film in which the pigment was uniformly dispersed.

24- How to make receiver paper A receiver paper was prepared according to the method of Example 1.

d) Transfer Recording Test and Results When recording was performed using the above sheet and image receiving paper according to the method of Example 1, the sheet and image receiving paper were not fused during recording (and the binder of the sheet was not fused to the image receiving paper). There was no transfer to the paper, and the sheet and image-receiving paper could be easily separated after recording.

In addition, the obtained recording had good resolution of each dot and exhibited a clear yellow color.

As shown in Table 7, the color density increased with application time.

However, the color density measurement was carried out using the same device as in Example 1, but the filter was used as a ratten boiled T? was used.

Example 6 a) Preparation of aqueous dispersion ink The ink prepared in Example aJ was further added with ethanol.
Add ml and in-? I got it.

The resulting ink had good dye dispersion stability.

b. Preparation of Sheet A sheet was obtained according to the method of Example 1 using the aqueous dispersion ink described above.

The obtained sheet has good hardness, and the above-mentioned water-based dispersion ink adheres firmly to the substrate.

The coating film had one pigment uniformly dispersed therein.

How to make QJ Uke 1 elephant paper A receiver paper was prepared according to the method of Example 1.

dJ Transfer Recording Test and Results Using the above sheet and image receiving paper, recording was carried out according to the method of Example 1. As a result, the sheet and the image receiving paper did not fuse together during recording, and the binder of the sheet did not adhere to the image receiving paper. After recording, the sheet and image receiving paper could be easily separated without any transition.

In addition, the obtained recording had good resolution of each dot, and showed a clear magenta color.

As shown in Table 1, the color density increased depending on the application time.

Table 7 (Recording color density) Applicant: Mitsubishi Chemical Industries, Ltd.

Claims (1)

[Scope of Claims] (1) A color thermal transfer recording sheet comprising a substrate and an aqueous dispersion ink containing a nonionic sublimable dye and a binder. (2. The color thermal transfer recording sheet according to claim 1, wherein the binder is a water-soluble or water-dispersible resin. (3) The color thermal transfer recording sheet according to claim 1. In the thermal transfer recording sheet, the binder is a water-soluble or water-dispersible polyester resin.'PI: Characteristics. (4) In the color thermal transfer recording sheet according to claim 2, the binder is a water-soluble or water-dispersible polyester resin. (5) The color thermal transfer recording sheet according to claim 1, wherein the binder is a water-soluble or water-dispersible polyester resin and a water-soluble polyester resin. Or a product characterized by being a mixture with a water-dispersible acrylic resin.