JP4152864B2 - Receptor for thermal transfer recording - Google Patents

Description

  The present invention relates to a thermal transfer recording receptor, and more particularly to a thermal transfer recording receptor in which a transfer image formed on the receptor is excellent in solvent resistance.

A thermal transfer recording medium provided with a heat-meltable ink layer is heated in an image-like manner by a heating means such as a thermal head, and the ink melted on the surface of the receptor layer usually provided with the receptor layer is used as the receptor. A thermal transfer recording method in which an image is formed on a receptor by transfer is generally known.
Regardless of the application, when the receiver is used in an environment where an organic solvent such as ethanol is used, it is necessary that the image transferred on the receiver is not erased by the organic solvent. Such a requirement is high in the case of a label having an adhesive layer or an adhesive layer on the side opposite to the surface on which the body receives an image, for example, a label such as a nameplate.

In order to obtain solvent resistance in the transferred image transferred on the receiver, a specific polyolefin is used as the same type of resin having excellent solvent resistance in the ink layer of the thermal transfer recording medium and the receptor layer of the receiver. Has been proposed (see, for example, Patent Document 1), and similarly, the use of polyester has been proposed (see, for example, Patent Document 2).
However, these methods cannot obtain a sufficient solvent resistance of an image.

Japanese Patent No. 25333456 Japanese Patent No. 3014954

  Accordingly, an object of the present invention is to provide a thermal transfer recording receptor having high solvent resistance of a transferred image in view of the above-described conventional technology.

The above-mentioned problem is (1) “a thermal transfer recording receiver in which a receiving layer is provided on a support made of a plastic film, wherein the receiving layer contains calcium and / or magnesium-containing pigment and ethylene-methacrylic acid. A receptor for thermal transfer recording comprising a salt of a copolymer and an epoxy compound, "
(2) “Receptor for thermal transfer recording according to item (1) above, wherein the pigment has a particle size of 2.5 to 4.0 μm”;
(3) “The thermal transfer recording receptor according to item (1) or (2), wherein the pigment is contained in the receiving layer in an amount of 50 to 90% by weight”;
(4) “Reception for thermal transfer recording according to any one of (1) to (3) above, wherein the smoothness of the receiving layer surface (JIS P-8119) is 500 to 1500 seconds. body",
(5) "The receptor for thermal transfer recording according to any one of items (1) to (4), wherein the receptor layer contains polyvinyl alcohol modified with a carboxylic acid Na group" , (6) "wherein the deposition amount of the receiving layer, characterized in that a 4~8g / m ² paragraph (1), second (5) for thermal transfer recording receptor according to any of claim",
(7) In the above items (1) to (6), wherein only the adhesive layer or the adhesive layer and the release paper are provided on the side of the support opposite to the receiving layer. This is achieved by the “receptor for thermal transfer recording” according to any of the above.
In addition, the above-mentioned problem is that (8) “The image of the image formed by heating the thermal transfer recording medium provided with the heat-meltable ink layer imagewise by the heating means and then melted on the surface of the receptor for thermal transfer recording” is described. A thermal transfer recording method for producing a recording body in which an ink image is formed on the surface of the thermal transfer recording receptor by transferring ink, wherein the thermal transfer recording receptor is the first (1) to (7). It is achieved by a “thermal transfer recording method characterized by using any one of the items”.
Further, the above-mentioned problem is a recording material having an ink image on the surface of a thermal transfer recording receptor, wherein the recording material is produced by the thermal transfer recording method described in (9) “(8) of the present invention”. Is achieved.

  As will be apparent from the following detailed and specific description, in a thermal transfer recording receiver in which a receiving layer is provided on a support made of a plastic film, the receiving layer contains a pigment having calcium and / or magnesium and an ethylene-methacrylic acid copolymer. The receptor on which a transfer image obtained by transferring an image from a thermal transfer recording medium using a thermal transfer recording receptor containing a polymer salt and an epoxy compound is formed in a solvent such as ethanol. A recording material having excellent resistance can be obtained.

The present invention is described in detail below.
As described above, in the thermal transfer recording receiver of the present invention, the support is a plastic film, the receiving layer provided on the support contains at least a resin and a pigment, and calcium and / or magnesium is used as the pigment. The pigment has an ethylene-methacrylic acid copolymer metal salt and an epoxy compound as the resin.
That is, in the thermal transfer recording receptor of the present invention having such a configuration, the image transferred onto the surface of the receptor layer of the receiver has excellent resistance to a solvent such as ethanol.
As the pigment to be contained in the receptor layer constituting the thermal transfer recording receptor of the present invention, a pigment having calcium and / or magnesium is used.
As the pigment having calcium and / or magnesium, for example, calcium carbonate, calcium silicate, magnesium hydroxide, magnesium carbonate and the like are used, and it is particularly preferable to use calcium carbonate.
Further, inorganic pigments and organic pigments other than pigments having calcium and / or magnesium can be used in combination.
Examples of such inorganic pigments and organic pigments include inorganic pigments such as aluminum hydroxide, silica, titanium oxide, kaolin, calcined kaolin, zinc oxide, and barium sulfate, urea-formalin resin, styrene-acrylic copolymer resin, polystyrene. And organic pigments such as
When used in combination, it is preferable to add the pigment having calcium and / or magnesium so that it is 50% by weight or more of the total amount of the pigment in the receiving layer.
Moreover, it is preferable that the particle size of the pigment contained in a receiving layer is 2.5-4.0 micrometers. If the thickness is less than 2.5 μm, the solvent resistance of the image transferred to the receiving layer tends to decrease, and if it exceeds 4.0 μm, the fineness of the transferred image tends to decrease.
Further, the content of the pigment in the receiving layer is preferably 50 to 90% by weight, and more preferably 60 to 75% by weight.
If it is less than 50% by weight, the solvent resistance of the transferred image tends to decrease, and if it exceeds 90% by weight, the receiving layer strength tends to decrease.

As one of the resins constituting the receptor layer of the thermal transfer recording receptor of the present invention, an ethylene-methacrylic acid copolymer salt is used.
The salt of the ethylene-methacrylic acid copolymer has a structure in which a part of methacrylic acid is crosslinked between molecular chains by cations such as Na, K, Ca, Zn and NH ₃ .
The salt of the ethylene-methacrylic acid copolymer is preferably added in an amount of 10 to 50% by weight in the receiving layer.
In the receiving layer in the present invention, a specific effect can be exhibited by combining a pigment having calcium and / or magnesium as the pigment and a salt of the ethylene-methacrylic acid copolymer.
As a specific example of this ethylene-methacrylic acid copolymer salt, for example, Chemipearl S manufactured by Mitsui Chemicals, Inc. can be used.

In the present invention, in addition to the salt of the ethylene-methacrylic acid copolymer, other resins can be added to the receptor layer as necessary.
Examples of such a resin include polyvinyl alcohol such as partially saponified polyvinyl alcohol, fully saponified polyvinyl alcohol, polyvinyl alcohol modified with carboxyl group, carboxylic acid Na group, sulfonic acid Na group, acetoacetyl group, cation group and the like. Alcohols, starch and derivatives thereof, cellulose derivatives such as methoxycellulose, hydroxyethylcellulose, carboxymethylcellulose, methylcellulose, ethylcellulose, polyacrylic acid, sodium polyacrylate, polyvinylpyrrolidone, acrylamide-acrylic acid ester copolymer, acrylamide-acrylic acid Ester-methacrylic acid terpolymer, styrene-maleic anhydride copolymer alkali salt, isobutylene-maleic anhydride copolymer alkali salt, polyacrylic Water-soluble resin such as sodium alginate, gelatin, polyvinyl acetate, polyurethane, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, styrene-butadiene-acrylic copolymer, polyacrylic acid, polyacrylic ester , Polymethacrylate, vinyl chloride-vinyl acetate copolymer, ethylene-vinyl acetate copolymer, vinyl acetate-acrylic acid copolymer, ethylene-vinyl acetate-acrylic acid copolymer, urethane-modified polyethylene, styrene-acrylic Examples include acid ester copolymers, ethylene-propylene copolymers, ethylene-vinyl chloride copolymers, vinyl acetate-ethylene-vinyl chloride copolymers, emulsions such as polyesters, and water dispersions.
In particular, it is preferable to add polyvinyl alcohol modified with a carboxylic acid Na group.
The amount of the resin other than the salt of the ethylene-methacrylic acid copolymer is preferably less than 10% by weight in the receiving layer.

Furthermore, as another resin constituting the receptor layer of the thermal transfer recording receptor of the present invention, it is necessary to add an epoxy compound in order to crosslink the resin and improve the solvent resistance and strength.
The epoxy compound is preferably added in an amount of 0.3 to 2.5% by weight in the receiving layer.
Although it does not specifically limit as this epoxy compound, A polyhydroxyalkane polyglycidyl ether type thing is preferable, and it is preferable to use especially an epoxy equivalent 140-350 mg / eq.

  The receiving layer of the thermal transfer recording receptor of the present invention can contain various additives such as lubricants such as higher fatty acid metal salts and paraffin wax, dispersants, antifoaming agents, etc., if necessary.

The receptor layer of the receptor for thermal transfer recording of the present invention is preferably formed on the support so as to be 4 to 8 g / m ² . If it is less than 4 g / m ₂ , the fineness of the transferred image tends to decrease, and if it exceeds 8 g / m ² , the solvent resistance of the transferred image tends to decrease.

  The thermal transfer recording receptor of the present invention is formed so that the surface of the receiving layer is smoothed (JIS P-8119) between 500 and 1500 seconds by forming a receiving layer and then surface-treating with a super calender or the like. It is preferable to do this. If it is less than 500 seconds, the fineness of the transferred image exceeds 1500 seconds, and the solvent resistance of the transferred image tends to decrease.

Examples of the plastic film for the support constituting the receptor for thermal transfer recording of the present invention include, for example, polyethylene terephthalate, polyethylene, polypropylene, polyvinyl chloride, polyethersulfone, polyphenylene sulfide, polyetherimide, polyetheretherketone, polyimide Nylon, vinylon, polyolefin synthetic paper, etc. are applied. In particular, polypropylene or polyester film is preferable in terms of strength, solvent resistance, and cost.
Specifically, examples of the polypropylene film include YUPO manufactured by YUPO Corporation, CARLESO manufactured by Chisso, Toyopearl manufactured by Toyobo, etc., and examples of polyester films include Lumirror made by Toray, Crisper manufactured by Toyobo, and Teijin.・ DuPont Tetron can be used.

The receptor for thermal transfer recording of the present invention can also have a configuration in which an under layer is provided between the support and the receptor layer as necessary.
For example, as the under layer, a layer having a porous structure or a layer containing a hollow filler can be provided in order to impart elasticity or heat insulation, and the adhesion between the support and the receiving layer can be improved. Therefore, a layer mainly composed of a resin can be provided.

  Further, in the thermal transfer recording receptor of the present invention, a pressure-sensitive adhesive layer that develops tackiness by heating is laminated on the surface of the support opposite to the receiving layer side, or an adhesive layer and a release paper are laminated. By adopting a structure in which layers are sequentially laminated, the receptor can be processed into a label form that can adhere (or adhere) to the adherend.

  In the thermal transfer recording receptor of the present invention, the total thickness of the support, the receiving layer, and the pressure-sensitive adhesive layer provided as necessary is preferably 40 to 250 μm. If the thickness is less than 40 μm, the strength of the receptor is lowered and is easily broken, and if it exceeds 250 μm, it tends to be caught and easily fall off when it is affixed to an adherend as a label.

  Next, the present invention will be described more specifically with reference to examples. In addition, a part here is a solid content weight reference | standard.

[Example 1]
Receptor layer formulation Aqueous dispersion of calcium carbonate (particle size 1.8 μm, solid content 25%) 56.0 parts Ethylene-methacrylic acid copolymer Na salt (solid content 27%) 21.5 parts Epoxy compound (epoxy equivalent 160 mg) / Eq solid content 100%) 0.2 parts water 22.3 parts The coating solution for forming a receiving layer having the above composition is applied to a polypropylene synthetic paper FPG made by YUPO Corporation to a thickness of about 6.0 μm. Dried to form a receiving layer. Then, the surface treatment was performed by the super calender, and the smoothness of the receptor surface was set to 1800 seconds.
The receptor thus obtained was subjected to an evaluation test by the following method.

(Printing conditions)
Thermal transfer recording medium: R110 B110C
Printer: 96Xi III manufactured by Zebra
Printing speed: 2 inches / second

The various characteristics evaluated are as follows.
(1) Image definition The image definition was visually evaluated according to the following criteria.
4 Good fineness 3 Somewhat fine 2 Good little fine 1 Poor fineness (2) Solvent resistance Solvent resistance 0.5cc of solvent is applied to the transfer image, and this sample is 100g / cm The sample was rubbed 50 times with a load of ² , and the image was observed and evaluated according to the following criteria. Ethanol was used as the solvent.
5 As a result of the love test, there is no change from before the test.
4 As a result of the love test, the image can be read but slightly damaged.
3 As a result of the love test, the image can be read but can be damaged.
2 As a result of the love test, the image remains but cannot be read.
1 The image is erased as a result of the love test.

[Example 2]
Receptor layer formulation Aqueous dispersion of calcium carbonate (particle size 4.2 μm, solid content 25%) 56.0 parts Ethylene-methacrylic acid copolymer Na salt (solid content 27%) 21.5 parts Epoxy compound (epoxy equivalent 160 mg) / Eq solid content 100%) 0.2 parts water 22.3 parts The coating solution for forming a receiving layer having the above composition is applied to a polypropylene synthetic paper FPG made by YUPO Corporation to a thickness of about 6.0 μm. Dried to form a receiving layer. Then, the surface treatment was performed by the super calender, and the smoothness of the receptor surface was set to 400 seconds.

Example 3
Receiving layer formulation Aqueous dispersion of calcium carbonate (particle size 3.7 μm, solid content 25%) 56.0 parts Ethylene-methacrylic acid copolymer Na salt (solid content 27%) 21.5 parts Epoxy compound (epoxy equivalent 160 mg) / Eq solid content 100%) 0.2 parts water 22.3 parts The coating solution for forming a receiving layer having the above composition is applied to a polypropylene synthetic paper FPG made by YUPO Corporation to a thickness of about 6.0 μm. Dried to form a receiving layer. Then, the surface treatment was performed by the super calender, and the smoothness of the receptor surface was set to 900 seconds.

Example 4
Receptor layer formulation Calcium carbonate aqueous dispersion (particle size 3.7 μm, solid content 25%) 53.2 parts Ethylene-methacrylic acid copolymer Na salt (solid content 27%) 21.5 parts Itaconic acid modified polyvinyl alcohol Na salt aqueous solution (solid content 10%) 7.0 parts Epoxy compound (epoxy equivalent 160 mg / eq solid content 100%) 0.2 parts Water 18.1 parts A coating solution for forming a receiving layer having the above composition has a thickness of about 60 μm. Was applied to and dried at about 6.0 μm on a polypropylene synthetic paper FPG made by YUPO Corporation, to form a receiving layer.
Then, the surface treatment was performed by the super calender, and the smoothness of the receptor surface was set to 900 seconds.

Example 5
Receiving layer formulation Aqueous dispersion of magnesium carbonate (particle size 3.2 μm, solid content 25%) 26.6 parts Magnesium hydroxide aqueous dispersion (particle size 2.9 μm, solid content 25%) 26.6 parts Ethylene-methacrylic acid Na salt of copolymer (solid content 27%) 21.5 parts Sodium salt aqueous solution of itaconic acid-modified polyvinyl alcohol (10%) 7.0 parts Epoxy compound (epoxy equivalent 160 mg / eq solid content 100%) 0.2 parts 18.1 parts of water The receiving layer-forming coating solution having the above composition was applied and dried to a thickness of about 6.0 μm on a polypropylene synthetic paper FPG made by YUPO CORPORATION having a thickness of about 60 μm to form a receiving layer.
Then, the surface treatment was performed by the super calender, and the smoothness of the receptor surface was set to 1100 seconds.

[Comparative Example 1]
Receiving layer formulation Aqueous dispersion of calcined kaolin (particle size 0.7 μm, solid content 25%) 56.0 parts Ethylene-methacrylic acid copolymer Na salt (solid content 27%) 21.5 parts Epoxy compound (epoxy equivalent 160 mg) / Eq solid content 100%) 0.2 parts water 22.3 parts The coating solution for forming a receiving layer having the above composition is applied to a polypropylene synthetic paper FPG made by YUPO Corporation to a thickness of about 6.0 μm. Dried to form a receiving layer.
Then, the surface treatment was performed by the super calender, and the smoothness of the receptor surface was set to 2100 seconds.

[Comparative Example 2]
Receptor layer formulation Aqueous dispersion of calcium carbonate (particle size 1.8 μm, solid content 25%) 56.0 parts Carboxylated SBR (LACSTAR DS-411, manufactured by Dainippon Ink & Chemicals, Inc.)
(Solid content 50%) 11.6 parts epoxy compound (epoxy equivalent 160 mg / eq solid content 100%) 0.2 parts water 32.2 parts A coating solution for forming a receiving layer having the above composition is manufactured by YUPO CORPORATION having a thickness of about 60 μm. The receiving layer was formed by applying and drying polypropylene synthetic paper FPG to a thickness of about 6.0 μm.
Then, the surface treatment was performed by the super calender, and the smoothness of the receptor surface was set to 1800 seconds.

[Comparative Example 3]
Receptor layer formulation Aqueous dispersion of calcium carbonate (particle size 1.8 μm, solid content 25%) 56.0 parts Na salt of ethylene-methacrylic acid copolymer (solid content 27%) 21.5 parts Water 22.5 parts The receiving layer-forming coating solution having the composition was applied and dried on a polypropylene synthetic paper FPG made by YUPO Corporation having a thickness of about 60 μm to form a receiving layer.
Then, the surface treatment was performed by the super calender, and the smoothness of the receptor surface was set to 1800 seconds.
The above evaluation results are shown in Table 1.

It can be seen from Table 1 that the thermal transfer recording receivers of the examples can obtain images having excellent resistance to solvents such as ethanol.

Claims (9)

A thermal transfer recording receiver having a receiving layer provided on a support made of a plastic film, the receiving layer containing a pigment having calcium and / or magnesium, a salt of an ethylene-methacrylic acid copolymer, and an epoxy compound A thermal transfer recording receptor. 2. The thermal transfer recording receiver according to claim 1, wherein the pigment has a particle size of 2.5 to 4.0 [mu] m. 3. The thermal transfer recording receiver according to claim 1, wherein the pigment is contained in the receiving layer in an amount of 50 to 90% by weight. The receptor for thermal transfer recording according to any one of claims 1 to 3, wherein the smoothness (JIS P-8119) of the surface of the receptor layer is 500 to 1500 seconds. 5. The thermal transfer recording receiver according to claim 1, wherein the receiving layer contains polyvinyl alcohol modified with a carboxylic acid Na group. The thermal transfer recording receiver according to claim 1, wherein the receiving layer has an adhesion amount of 4 to 8 g / m ² . 7. The thermal transfer recording receiver according to claim 1, wherein only the adhesive layer or the adhesive layer and the release paper are provided on the side of the support opposite to the receiving layer. After the thermal transfer recording medium provided with the heat-meltable ink layer is heated imagewise by a heating means, the melted image-like ink is transferred onto the surface of the thermal transfer recording receptor, and the surface of the thermal transfer recording receptor A thermal transfer recording method for producing a recording body having an ink image formed thereon, wherein the thermal transfer recording receiver is the one according to any one of claims 1 to 7. A recording material having an ink image on the surface of a thermal transfer recording receptor, which is produced by the thermal transfer recording method according to claim 8.