JPS62187092A - Thermal transfer recording sheet - Google Patents

Abstract

PURPOSE:To eliminate the generation of blocking at the time of thermal transfer, by applying a coating agent based on a specific polyester resin to the surface of a support sheet and, after drying, irradiating the coating layer with active energy to cure the resin. CONSTITUTION:The secondary non-conjugated amino group of a polyester resin having said secondary amino group is reacted with the epoxy group of a compound having an active energy beam curable double bond and said epoxy group to obtain a polyester resin having a tertiary non-conjugated amino group and the active energy beam curable double bond. This polyester resin is dissolved in a solvent such as acetone to prepare a coating solution with resin content of 5-60wt% and this coating solution is applied to the surface of a support sheet and dried. Subsequently, the coated support sheet is irradiated with active energy beam such as ultraviolet rays to cure the polyester resin to obtain a thermal transfer recording sheet having a transfer recording layer provided thereto.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a method for obtaining a transfer record with good color development without blocking (thermal fusion) when thermally transferred using a sublimable dye. The present invention relates to a thermal transfer recording sheet that can be used.

[Prior art]

Thermal transfer technology to film and paper using sublimable dyes has good color reproducibility and is easy to use because it uses Rij delivery.
Its future potential is seen as very promising for use as a glitter in equipment A. In other words, a number fm@ with different sublimation temperatures and hues.
Full-color recording with excellent gradation reproducibility is easily possible by sublimation-transferring the dye by changing the heating temperature.

This sublimation thermal transfer method uses dyes that sublimate with heat, so the transfer recording layer has poor light resistance, and when stored for a long time, color development sensitivity and density decrease, resulting in unstable images and gradual discoloration. have In particular, when a disperse dye is used as a sublimable dye, the resolution and color tone of the image are likely to change. For this reason, it is necessary to provide the image-receiving sheet with a polymer layer such as polyester or polyacetate.

However, since these polymers such as polyester and polyacetate are thermoplastic resins, when a transfer sheet containing a sublimable dye is placed on an image-receiving sheet for thermal transfer,
Heat melts thermoplastic polymers such as polyester and polyacetate, causing the transfer sheet to adhere to the image-receiving sheet, resulting in blocking when the two are peeled off, and even worse, heat fusion, causing the transfer sheet and image-receiving sheet to become stuck. If you try to forcefully pull off the sheet, one of the sheets will be torn. This phenomenon occurs more markedly as the sublimation temperature of the sublimation dye is higher, and conversely, there is a demand that it is better to use a sublimation dye with a high sublimation temperature in order to obtain transfer records with excellent light resistance and long-term storage stability. It is inconsistent with the means to achieve performance.

[Problem that the invention seeks to solve]

There is a strong desire among those skilled in the art to obtain a transfer record with good color development, light resistance, and long-term storage stability without blocking or heat-sealing during transfer.

The purpose of the present invention is to prevent blocking or heat fusing when thermally transferred using a sublimable dye as described above.
It is an object of the present invention to provide a thermal transfer recording sheet capable of obtaining a transfer record Qt with good color development.

[Specific measures to solve the problem]

In the present invention, a coating agent mainly composed of a polyester resin having a non-conjugated tertiary amino group and an active energy ray-curable double bond is applied onto the base material of an image-receiving sheet, and after drying, active energy rays are applied. By curing the resin by irradiation, a transfer recording sheet is provided in which an image-receiving layer is formed on a support, and this sheet does not block when thermally transferred using a sublimable dye. Transfer records with good color development can be obtained.

The I-lyester resin having a non-conjugated tertiary amine group and an active energy ray-curable double bond used in the present invention has a molecular weight of 5,000 to soo, ooo, preferably an IQ of 000 to 300,000. It is a resin obtained by reacting the secondary amine group of an I-reester resin having a non-conjugated secondary amino group with the epoxy group of a compound having an active energy ray-curable double bond and an epoxy group. .

This I-reester resin having a non-conjugated secondary amino group is a resin obtained by reacting /IJol having a non-conjugated secondary amino group with polycarmenic acid or its acid anhydride. .

The polyol having a non-conjugated secondary amino group, which is the raw material for the polyester resin having a non-conjugated secondary amino group, is the total amount used, j? 0.1 to IJ all 1 sole
The ratio is preferably 0.5 mol, and if it is more than 0.5 mol, the produced I-reester resin may turn yellow, or in some cases turn brown, and when formed into a coating, the image-receiving layer may deteriorate. It becomes colored and becomes inconvenient. On the other hand, if the amount is less than 0.1 mol, the coloring property will be poor and blocking will occur easily when thermal transfer is performed using a sublimable dye.

The use of a compound having an active energy ray-curable double bond and an epoxy group is 0.1 to 1 for the secondary amine group of the polyester resin having a non-conjugated tertiary amino group.
．． OI equivalent ratio, preferably 0.2 to 1.0 g equivalent ratio. 0. If the ratio is lower than the II equivalent ratio, curing by active energy rays will be insufficient and blocking will likely occur during thermal transfer. When the equivalent ratio is more than 1.011, the compound having a double bond and an epoxy group remains unreacted, causing gelation and deterioration during storage.

Examples of the raw materials used include the following:

As a polyol having a non-conjugated secondary amino group,
Jetanolamine, dipropanolamine, digtanolamine, dipentanolamine, etc., and other polyols include ethylene glycol, diethylene glycol, triethylene glycol, /IJ f V 7 /
"R-r-k, propylene glycol, polypropylene glycol, butylene glycol, neopentyl glycol, trimethylolpropane, pentaerythritol, etc. are used.

? Rikar? Oxalic acid or its acid anhydride includes oxalic acid,
Malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, maleic acid, phthalic acid, 0-phthalic acid, m-phthalic acid, terephthalic acid, trimellitic acid, or acid anhydrides thereof are used.

Examples of the compound having an active energy E beam-curable double bond and an epoxy group include glycidyl acrylate, glycidyl methacrylate, allylclycidyl 1-tyl, styryl glycidyl ether, and glycidyl cinnamate.

This resin is usually methyl ethyl ketone, methyl imbutyl ketone, acetone, diacetone alcohol, benzene, toluene, etc. f) Solvent K When dissolved, the resin content is 5 to 60.
Used as a coating agent in weight percent. In order to improve the condition of the paint film, etc., we also use higher alcohol ethoxylates. This coating agent contains acrylates and diacrylates of realkylene glycol, triacrylates such as pentaerythritol triacrylate and trimethylolgulonoyant triacrylate, fillers such as silicone resin, fluororesin, clay, carbonaceous, and silica. It is useful to add.

The coating agent includes air knife coat, blade coat,
It is coated onto a support such as glass film, paper, coated paper, resin-impregnated paper, synthetic paper, metal sheet, etc. by barcode, gravure coating, curtain coating, roll coating, spray coating, etc., and then dried. After drying the solvent, the polymerizable resin is crosslinked by irradiation with active energy rays to form an image receiving layer on the base sheet (support). The coating wave of the recording layer is 0.1 to 20117 m in solid content.
'', preferably in the range of 0.5 to 10Ji'7m2.

Commonly used active energy rays include ultraviolet rays and high-energy ionizing radiation. When using ultraviolet rays, a photoreaction initiator that absorbs the ultraviolet rays, generates rajal, and initiates polymerization in an amount of 0.5 to 5 per 100 parts by weight of the resin, and if necessary, an accelerator must be added. . Examples of photoreaction initiators include benzophenone, Michler's ketone, methyl 0-benzoylbenzoate, 4
, 4'-bisdiethylaminobenzophenone, 4.4
benzophenones such as '-bischlorobenzophenone,
Benzoin alkyl ethers such as penzoinmethyl, benzoinethyl, penzoinglovir, benzoingthyl, ketals such as benzyl dimethyl ketal, acetophenone diethyl ketal, chloroOfoxanthone,
Thioxanthone such as methylthioxanthone and globylthioxanthone, dibenzyls, etc. can be used. The photoreaction initiator is used in a proportion of 0.05 to 5% by weight of the polymerizable resin.

Examples of amines that can be used as accelerators include triethanolamine, jetanolamine, ethanolamine, triple Φ amine, dialkylamine, and alkylamine.

The amount of amine used is 0.001 to 3 parts by weight per 100 parts by weight of polymerizable fl fat. UV+%1i111X
Examples include ultraviolet edge wall lights and low-pressure mercury lamps.

High-pressure mercury lamps, ultra-high-pressure mercury lamps, mercury lamps, carbon arc lamps, sunlight, etc. can be used.

When using high-energy ionizing radiation, there is no need to use a photoreaction initiator or the like. As high-energy ionizing radiation, for example, electron beams accelerated by accelerators such as Kotscroft deaf accelerator, Vandegraaf type accelerator, Ligner accelerator, betatron, and cyclotron are the most convenient and economical to use industrially. However, in addition to radioactive isotopes and
Radiation such as rays, alpha rays, beta rays, neutron beams, and proton beams can also be used.

The present invention will be explained in more detail below with reference to Examples, but the present invention is not limited to these Examples in any way.

Note that parts in the examples are based on weight.

Manufacturing example resin! 21 parts (0.2 mol) of jetanolamine in the flask
, 49.6 parts (0.8 mol) of ethylene glycol, 148 parts (1.0 mol) of phthalic anhydride, a small amount of para-toluenesulfonic acid as a catalyst, and a small amount of xylene for azeotropic distillation of by-product water, The reaction was carried out at 220° C. for 4 hours, and 17.5 parts of 97 tons of theoretical raw water were distilled off.

After the reaction, xylene was distilled out of the system, and methyl ethyl ketone was added to obtain a polyester resin liquid with a concentration of 50%.

Next, 25.6 parts of glycidyl acrylate (
0.2 mol), 0.026 part of hydroquinone monomethyl,
0.8 part of penzyltrimethylammonicum hydroxide was added, and the mixture was reacted for 8 hours, and methyl ethyl ketone was further added to obtain m fltj I (50% concentration in methyl ethyl keto y).

This resin 1 was pale yellow and transparent, and had a molecular weight of about 100,000 containing the following units in its molecular chain.

-Resin ■ As in the case of resin ■, diglobanolamide: / 53
．． 2 parts (0-4 mol), neopentyl glycol 62
．． 4 parts (0.6 mol), 148 parts (1.0 mol) of anhydrous phthalic powder
), a small amount of para-toluenesulfonic acid, and a small amount of xylene were charged and reacted at 230° C. for 3 hours to obtain a polyester resin.

Next, methyl ethyl ketone was added, and at 60°C, 42.6 parts (0.3 mol) of glyphyl methacrylate, 0.043 parts of hydroquinone monomethyl, and 1.3 parts of tetramethylammonium bromide were added, and the mixture was allowed to react for 10 hours. Then, methyl ethyl ketone was further added to obtain resin (50% concentration in methyl ethyl ketone).

This resin (2) was pale yellow and transparent, and had a molecular weight of approximately 70,000 containing the following unit in its molecular chain.

Comparison resin! As in the case of 1fJJ fat I, jetanolamine 5.
3 parts (0.05 mol), 58.9 parts (0.95 mol) of ethylene glycol, 148 m (1.0 mol) of phthalic anhydride, a small amount of para-toluenesulfonic acid, and a small amount of xylene, and A polyester resin was obtained by reacting for a period of time.

Next, methyl ethyl ketone was added, and 6.4 parts (0.05 mol) of glycidyl acrylate, 0.006 parts of hydroquinone monomethyl, and 0.2 parts of benzyltrimethylammonium hydroxide were added at 60°C and reacted for 10 hours. In addition, a pale yellow transparent comparative resin I (concentration of 5OL4 in methyl ethyl ketone) having a molecular weight of about 110,000 was obtained.

Comparative resin ■ As in the case of resin ■, jetanolamine 63m (0
, 6 moles), 30.4 parts of glopylene glycol (0.4 parts
mol), 148 parts (1.0 mol) of phthalic anhydride, a small amount of para-toluenesulfonic acid, and a small amount of xylene.
The mixture was reacted at 220°C for 4 hours to obtain a polyester resin.

Next, methyl ethyl ketone was added, and 71 parts (0.5 mol) of glyc7dyl methacrylate, 0.071 parts of hydroquinone monomethyl, and 2.1 parts of tetramethylammonium bromide were added at 60°C and reacted for 10 hours. Add the molecules to about 80,000 brown comparisons 4N) 1
111 (50% concentration in methyl ethyl ketone) was obtained.

Comparative resin■ Same as resin■, diglobanolamine 39.9
part (0.3 mol), 43.4 parts (0.3 mol) of ethylene glycol
, 7 mol), 148 parts (1.0 mol) of phthalic anhydride, a small amount of para-toluenesulfonic acid, and a small amount of xylene were reacted at 230°C for 3 hours, and then diluted with methyl ethyl ketone to give a light yellow transparent color. Resin (1) (50% concentration in methyl ethyl ketone) was obtained.

Next, examples and comparative examples using the above-mentioned resin coating liquid will be explained.

A 40% methyl ethyl ketone solution of a composition containing 100 parts of the non-conjugated tertiary amino group and active energy heso-curable double bond gold-containing polyester tsukuda coating liquid listed in Table 1 and 3 parts of benzoinethyl. was applied to a polyester film with a thickness of 100 microns or one-sided art paper with a tsubo Q of 8097 m'' using a percoater to give a solid coating weight of 3, SF.
It was applied to a length of 7 m.

After drying, the conveyor speed was set to 1 using an ultraviolet irradiation device (manufactured by Nippon Battery Co., Ltd.; lamp strength: 80 W/cm).
A transparent film for recording was obtained by curing with ultraviolet light at 01nZ.

Example 2 A methyl ethyl ketone 40% solution of the resin coating solution shown in Table 1 was applied to a -lyester film using a percoater so that the solid content coating amount was 31/m'', and after drying,
Acceleration voltage 150 kV, current 2.0 using electronic helix irradiation device f (Electro Curtain, manufactured by Energy Science Co., Ltd.)
Electron beam irradiation i at mA 1. A transparent recording film was obtained by OM rad irradiation.

A 40% solution of the resin listed in Table 1 in methyl ethyl ketone was applied to a polyester film using a percoater so that the solid coating amount was 317 m'' and dried to obtain a transparent film for recording.

Only the transparent recording films of Examples 1 to 4, Comparative Examples 1 to 4, and conventional polyester film (Comparative Example 5)
, and single-sided art paper (Comparative Example 6) were added, and sublimation heat-sensitive transfer properties were evaluated by the following method.

(1) 6 coating coloring The presence or absence of yellowing and browning of the coating film was visually evaluated.

(2)・Presence or absence of 10 marking during thermal transfer, color development 1I
Apply a 15% ethanol solution of Blue A 2R (manufactured by Nippon Kakei Co., Ltd.)/methyl cellulose (6/Affi ratio) to i15017m" high-quality paper using a percoater until the solid coating amount is 3117m". I made a transfer paper by wiping it out and drying it like this.

Next, the coated sides of this transfer paper and the image-receiving sheets of Examples 1 to 4 and Comparative Examples 1 to 6 were placed on top of each other, and after hot pressing for 20 seconds with a heat sink at 160°C, the transfer paper and image-receiving sheet were peeled off. Blocking was evaluated. Thereafter, the color density of the transfer dye was measured on the image-receiving sheet using a Photogelt colorimeter (manufactured by Tokyo Kanshokusha) (filter: amber) (the smaller the number, the higher the color density).

The results are shown in Table 1. The image-receiving sheets of Examples 1 to 4 according to the present invention had no discoloration of the coating film, no blocking during transfer, and good transfer color development with high color density.

Claims (1)

[Scope of Claims] 1) A coating agent whose main ingredient is a polyester resin having a nonconjugated tertiary amino group and an active energy ray-curable double bond is applied to the surface of the support sheet, and after drying, an activated A thermal transfer recording sheet provided with a transfer recording layer on the surface of a support that can be thermally transferred using a sublimable dye by curing the resin by irradiating energy rays. 2) A polyester resin having a non-conjugated tertiary amino group and an active energy ray-curable double bond is combined with a secondary amino group of a polyester resin having a non-conjugated secondary amino group and an active energy ray-curable double bond. The thermal transfer recording sheet according to claim 1, which is a resin obtained by reacting a compound having a double bond and an epoxy group with an epoxy group. 3) The polyester resin having a non-conjugated secondary amino group is a resin obtained by reacting a polyol having a non-conjugated secondary amino group with a polycarboxylic acid or its acid anhydride. A thermal transfer recording sheet according to claim 2.