JPH0513074B2 - - Google Patents

Description

[Detailed description of the invention]

Object of the Invention (a) Industrial Application Field The present invention relates to a heat-sensitive recording sheet set comprising a transfer sheet having a dye layer on a support and a recording sheet having a recording layer on the base. be. (b) Prior Art In office automation terminals such as facsimile machines, printers, and copiers, which have become rapidly 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. On the other hand, it is desired to develop a technology for recording television images in color. Currently, color recording techniques using electrophotography, inkjet, and thermal transfer systems are being considered for these purposes. Among these methods, the thermal transfer method is advantageous over other methods because the device is easy to maintain and operate, and the device and consumables are inexpensive. Thermal transfer methods include the melting method, in which a dye layer formed on a support is heated and melted by a heat-sensitive head, and transferred and recorded onto the recording medium, and the other is a heat-sensitive transfer method, in which a dye layer containing a sublimable dye is formed on a support. There is a sublimation method, in which the dye is heated by a head to sublimate it and then transferred and recorded onto the recording medium.With the sublimation method, the amount of sublimation and transfer of the dye can be controlled by changing the energy given to the heat-sensitive head, resulting in gradation. It is easy to record and is considered to be particularly advantageous for full-color recording. It is desirable that the dye used in the above sublimation method be one that sublimates as easily as possible in order to reduce the burden on the heat-sensitive head and increase the recording speed. Under environmental conditions, the dye re-sublimates from the recording material, deteriorating the recording, or transfers to a contact object, causing contamination, which poses problems in the maintenance stability of the recording after transfer. One possible solution to this problem is to laminate the surface of the recording medium with a resin film after transfer recording to prevent re-sublimation. However, such a method requires materials and equipment for laminating, and the entire equipment becomes larger and more complicated, so further improvements are desired. (C) Objective The object of the present invention is to provide a heat-sensitive recording sheet set consisting of a transfer sheet and a recording material sheet for obtaining transfer recording with excellent storage stability. Structure of the Invention The present invention is a heat-sensitive recording sheet set consisting of a transfer sheet having a dye layer on a support and a recording material sheet having a recording layer on the substrate, the dye layer containing a dye having an epoxy group. However, the gist thereof is a heat-sensitive recording sheet set whose recording layer contains an active hydrogen compound or an organic acid anhydride. The epoxy group-containing dye used in the present invention includes azo-, anthraquinone-, naphthoquinone-, quinophthalone-, styryl-, and azomethine-based dyes having the epoxy group. (1) As an azo dye, the general formula () (In the formula, A ¹ represents a fuel group, benzothiazole group, imidazole group, or thienyl group that may have a substituent, R ¹ represents a hydrogen atom, an alkyl group, or an alkylcarbonylamino group, and R ² represents a hydrogen atom, an alkyl group, or an alkylcarbonylamino group. Representing an alkyl group), azo dyes and the like can be mentioned. Specifically, for example, the following may be mentioned. (2) As an anthraquinone dye, for example, general formula () or general formula () (In the formula, R ³ and R ⁴ are hydrogen atoms, alkyl groups, or

Represents a group represented by [Formula], R ⁵ is a hydrogen atom or

It represents a group represented by the formula: R ⁶ and R ⁷ represent a hydrogen atom or an alkyl group. However, when R ³ and R ⁴ are both hydrogen atoms or alkyl groups, R ⁵ is

Represents a group represented by [Formula]. ) and the like are mentioned. Specific examples include the following. (3) As naphthoquinone dyes, for example, general formula () or general formula () (In the formula, R ³ is a hydrogen atom, an alkyl group, or

Represents a group represented by [Formula]. ) Examples include naphthoquinone dyes shown in the following. Specifically, for example, the following may be mentioned. (4) Quinophthalone dyes include, for example, the general formula () (In the formula, -X- represents -O- or -NH-.) Quinophthalone dyes and the like can be mentioned. Specifically, for example, the following may be mentioned. (5) As styryl dyes, for example, general formula () (In the formula, R ⁹ represents a hydrogen atom or a cyano group, and R ¹ and R ² have the same meanings as above.) Styryl dyes and the like can be mentioned. Specifically, for example, the following may be mentioned. (6) As the azomethine dye, for example, the general formula () (In the formula, A ² is

【formula】

【formula】

[Formula] Also teeth

It represents a group represented by the formula: R ¹⁰ , R ¹¹ and R ¹² represent an alkyl group, R ¹³ represents a hydrogen atom or an alkylaminocarbonyl group, and R ¹ and R ² have the same meanings as above. ) and the like. Specifically, for example, the following may be mentioned. Next, a method for creating a transfer sheet will be explained. The transfer sheet can be obtained by mixing the above dye with a suitable resin, solvent, water, etc. to prepare an ink, and then coating the ink on a suitable support and drying it to form a dye layer. . As the resin for preparing the above ink,
Those having a high melting point or softening point are suitable, and specific examples include the following. Phenol resin, melamine resin, urethane resin, epoxy resin, silicone resin, urea resin, diallyl phthalate resin, alkyd resin,
Acetal resin, acrylic resin, methacrylic resin, polyester resin, starch and its derivatives, cellulose resin, polyvinyl chloride, polyvinylidene chloride, fluororesin, chlorinated polyethylene, polyethylene, polypropylene, polystyrene, polyvinyl acetal, polyamide, polyvinyl alcohol , polycarbonate, polysulfone, polyether sulfone, polyethylene terephthalate, polybutylene terephthalate, polyphenylene oxide, polyphenylene sulfide,
Polyethylene naphthalate/polyacrylonitrile, polyimide, polyamide, AS resin, ABS resin. Particularly preferred are inert resins such as polysulfone, polyethersulfone, polyethylene terephthalate, and polycarbonate. In addition, as solvents for ink preparation, alcohols such as methanol, ethanol, propanol, and butanol, cellosolves such as methyl cellosolve and ethyl cellosolve, aromatics such as benzene, toluene, xylene, and chlorobenzene,
Esters such as ethyl acetate and butyl acetate, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone, hydrocarbons such as ligroin, cyclohexane, and kerosene, chlorinated solvents such as chloroform, methylene chloride, and trichloroethylene, dimethyl formamide, etc. However, when using an aqueous resin, water or a mixture of water and the above-mentioned solvent can be used. Particularly preferred are inert solvents such as benzene, toluene, xylene, chlorobenzene, acetone, methyl ethyl ketone, chloroform, and methylene chloride. Supports for the transfer sheet include condenser paper, thin paper such as glassine paper, polyester,
Plastic films with good heat resistance such as polyamide and polyimide are suitable, but these supports need to be thin in order to improve the efficiency of heat transfer from the heat-sensitive recording head to the dye, and the thickness must be 50 μm or less. is suitable, and preferably 20 μm or less. Next, a method for creating a recording medium sheet will be explained. The recording medium sheet of the present invention can be obtained by applying a coating liquid containing an active hydrogen compound or an organic acid anhydride onto a suitable substrate, such as paper or resin film, and drying it to form a recording layer. It will be done. At that time, the coating solution contains resins such as polyester, polyamide, polyacrylic, silica, alumina, etc.
Inorganic fine particles such as calcium carbonate may also be added. Examples of the active hydrogen compound include various known high-molecular compounds or low-molecular compounds having a hydroxyl group, a mercapto group, a carboxyl group, an amino group, a monoalkylamino group, an amide group, preferably a hydroxyl group, a carboxyl group, or an amino group. can be mentioned. Specific examples include the following. (A) Compound with OH group (B) Compound with mercapto group

【formula】

【formula】

[Formula] (C) Compound having a carboxyl group (D) Compounds having an amino group, monoalkyl group, or amide group H ₂ NCH ₂ CH ₂ NH ₂ H ₂ NCH ₂ CH ₂ NHCH ₂ CH ₂ NH ₂ (CH ₃ ) ₂ NCH ₂ CH ₂ CH ₂ NH ₂ HOCH ₂ CH ₂ NHCH ₂ CH ₂ NHCH ₂ CH ₂ OH H ₂ NNHCO(CH ₂ ) ₄ CONHNH ₂ (E) Compounds with different groups Furthermore, examples of organic acid anhydrides include the following. To perform thermal transfer recording using the transfer sheet and recording material sheet obtained above, the ink-coated surface of the transfer sheet and the coating liquid-coated surface of the recording material sheet are overlapped, and the back side of the transfer sheet is It can be heated and pressurized using a heat-sensitive recording head. Effects of the Invention When transfer recording is performed by the above method, the dye in the dye layer of the transfer sheet is sublimated and transferred onto the recording material sheet, and at the same time, the dye having an epoxy group is transferred to the recording material sheet. The dye is fixed by reacting with an active hydrogen compound in the layer, such as a compound having a hydroxyl group, a mercapto group, a carboxyl group, an amino group, a monoalkylamino group, an amide group, or an organic acid anhydride. It is thought that excellent records can be obtained. As is clear from the above explanation and the examples described later, records with excellent storage stability can be easily obtained by the present invention. EXAMPLES The present invention will be specifically explained below with reference to Examples, but these Examples are not intended to limit the present invention. ExamplesExample 1 1 Method for creating a transfer sheet The above structural formula () dye: 2 g Ethyl cellulose: 8 g Isopropanol: 90 g Total: 100 g A mixture of the above composition was mixed with a paint conditioner using glass beads for about 30 minutes,
The ink was prepared. Apply the above ink to a gravure proofing machine (plate depth 30μm)
A transfer sheet was prepared by coating capacitor paper (thickness: 10 μm) and drying it naturally. 2 How to create a recording material sheet Compound of the above structural formula () 5 g Polyester resin ^* 15 g Methyl ethyl ketone 80 g Total 100 g * "Vylon 200" (trade name) manufactured by Toyo Boseki Co., Ltd. The above compositions were mixed to prepare a coating solution. Apply the above coating liquid to a gravure proofing machine (plate depth 30μm)
A recording medium sheet was prepared by applying the mixture to high-quality paper and drying it naturally. 3 Transfer recording method The ink coated surface of the transfer sheet is overlapped with the coating liquid coated surface of the recording material sheet, and the transfer sheet is heated from the back side using a heat-sensitive recording head to make a clear dark orange record on the recording material. I was able to get it. In order to test the stability of the records obtained in this way, the recording surface was superimposed on high-quality paper and held at 80°C for 24 hours under a pressure of 200 g/cm ² , but the color change of the records and the overlapping of high-quality paper There was almost no contamination by the dye. Reference Example 1 (Synthesis of dye of Example 1) 14 g of N-ethylaniline, epichlorohydrin
14.8 g, 10 ml of water, and 15 ml of ethanol were added, and the mixture was reacted and stirred on a water bath for 3 hours. After cooling, it was separated using an aqueous funnel and dried over sodium sulfate. The obtained N-ethyl-N-(2-oxy-3-
While cooling 21 g of aniline (chloropropyl) on ice,
8 ml of 50% aqueous sodium hydroxide solution was gradually added with stirring. Thereafter, after stirring for 4 hours, the produced sodium chloride was separated, and the organic layer was washed with water in a separating funnel and then dehydrated with sodium sulfate. A dye represented by the following structural formula () was obtained by coupling the obtained N-ethyl-N-glycidylaniline with a diazo solution of p-nitroaniline. mp 159-162°C Mass spectrum M ⁺ 326 λmax (chloroform) 474 nm Comparative example 1 1 Method for creating a transfer sheet A transfer sheet was created in the same manner as in Example 1. 2. Method for preparing a recording material sheet A coating solution was prepared by dissolving 15 g of polyester resin (Vylon 200) in 85 g of methyl ethyl ketone without using the compound () in Example 1, and a high-quality coating was prepared in the same manner as in Example 1. A recording medium sheet was prepared by applying the mixture to paper. 3 Transfer Recording Method The above transfer sheet and recording material sheet were superimposed and transfer recording was performed in the same manner as in Example 1 to obtain a dark yellow record. Example 1 regarding records obtained in this way
As a result of a stability test conducted in the same manner as above, the stacked high-quality paper was significantly stained orange due to migration of the dye from the recording material sheet. Furthermore, the color density of the recording material sheet was also significantly lowered due to the migration of the dye. Example 2 A dye having the structural formula shown in Table 1 was used instead of the dye shown in Example 1, and transfer recording was performed in the same manner as in Example 1, and a record with good storage stability was obtained. I was able to get it.

【table】

【table】

【table】

【table】

Claims (1)

[Claims] 1 A heat-sensitive recording sheet set consisting of a transfer sheet having a dye layer on a support and a recording sheet having a recording layer on a substrate, the dye layer containing a dye having an epoxy group, and the recording layer containing a dye having an epoxy group. A heat-sensitive recording sheet set containing active hydrogen compounds or organic acid anhydrides.