JPH05193279A - Dye thermal transfer image receiving sheet - Google Patents

Abstract

PURPOSE:To provide a dye thermal transfer image receiving sheet wherein lightfastness of a printing image is extremely improved. CONSTITUTION:In a dye thermal transfer image receiving sheet, an image receiving layer fixing by receiving a dye image is obtained wherein (1) an active energy beam setting resin and C2) a plasticizer consisting of at least one kind selected from dicyclophthalic acid ester, diallylphthalic acid ester, dioctyl adipate, and triphenyl phosphate are contained, and a mixed amount of the plasticizer (2) is 5-40 pts.wt. to 100 pts.wt. of the active energy beam setting resin (1).

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a dye thermal transfer image receiving sheet. More specifically, the present invention relates to a dye thermal transfer image receiving sheet excellent in light resistance of a printed image.

[0002]

2. Description of the Related Art In recent years, a thermal transfer type high-quality color hard copy, especially a dye thermal transfer type printer has been rapidly developed. In the dye thermal transfer printer, the sublimation dye layers of three colors (yellow, magenta, cyan) are heated by continuously controlling the heating energy of the thermal head, and the transfer amount of the dye of each color is changed. It enables the formation of full-color images with density gradation.

In order to obtain a high-quality image on the dye thermal transfer image-receiving sheet, a dyeing resin for an image-receiving layer is required which has a high dye transfer rate, a large dyeing amount, and good storability. .. Conventionally, various polyester resins have been used as a dyeing resin having such a high transfer rate and a large dyeing amount and excellent storage stability.

For example, JP-A-57-107885 discloses the use of a saturated polyester resin, and JP-A-61-3796 proposes to use a sulfonated phthalic acid-modified polyester resin. ing.
Further, JP-A-63-7971 discloses that a phenyl group-containing polyol and a dicarboxylic acid are used and have a molecular weight of 1
The use of 0000 to 30,000 polyester resins has been proposed. However, the light resistance of an image obtained by the dye thermal transfer method of these prior arts is not always sufficient, and further improvement of the light resistance of the image has been desired.

To improve the light fastness of an image, for example, JP-A-61-32789 and JP-A-61-2.
No. 29594 discloses a method of incorporating an ultraviolet absorber that absorbs ultraviolet rays of 300 to 400 nm and a method of incorporating a light stabilizer. However, although the effect of preventing discoloration can be seen by the addition of the ultraviolet absorber, it is accompanied by a change in image and color tone and yellowing in the non-printed portion, and therefore, it has not reached a sufficiently satisfactory level for practical use.

[0006]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned drawbacks of the prior art and provides a dye thermal transfer image-receiving sheet having excellent image storability of a dye image thermally transferred from an ink sheet to light. It is a thing.

[0007]

The inventors of the present invention have conducted extensive studies to obtain a dye thermal transfer image-receiving sheet capable of forming a transfer image having excellent light resistance, and as a result, as a resin for forming an image-receiving layer, the active energy It is found that the above-mentioned problems of the dye thermal transfer image-receiving sheet can be solved by using a so-called active energy ray-curable resin that is cured by irradiating a ray, and by further adding a specific amount of a specific plasticizer, and the present invention is provided. completed.

That is, the dye thermal transfer image-receiving sheet of the present invention comprises a sheet-like support and an image-receiving layer which is formed on at least one surface of the support and which receives a dye which is transferred from an ink sheet by heating. And the image receiving layer has (1) an active energy ray-curable resin,
(2) a plasticizer, wherein the plasticizer (2) comprises at least one selected from dicyclohexyl phthalate ester, diallyl phthalate ester, dioctyl adipate, and triphenyl phosphate; The content of 2) is 5 to 40 parts by weight with respect to 100 parts by weight of the active energy ray-curable resin (1).

[0009]

In JP-A-61-164893, a method is disclosed in which a plasticizer is added to a resin for forming an image receiving layer such as a polyester resin to form a fine porous structure inside the image receiving layer to improve sensitivity. Has been done. However, the above-mentioned prior art has no disclosure about improving the light resistance by incorporating a specific amount of a specific plasticizer into the image receiving layer resin. Further, when a plasticizer is added to a thermoplastic resin such as a polyester resin used in a conventional image-receiving layer resin, blocking may occur in winding after coating and drying, or,
There is a problem that the ink sheet and the image receiving layer are fused during printing. Furthermore, even if a plasticizer is added, no fine porous structure is formed inside the image receiving layer of the present invention.

The present invention solves the problems of blocking and fusion in the prior art by using an active energy ray-curable resin as the image-receiving layer forming resin, and further adding a specific amount of a specific plasticizer to the solution. As a result, the light resistance of the printed image is improved.

The plasticizer used as an essential component in the present invention is at least one selected from dicyclohexyl phthalate ester, diallyl phthalate ester, dioctyl adipate and triphenyl phosphate. These plasticizers are used as active energy ray curable resin 1
By blending 5 parts by weight to 40 parts by weight with respect to 00 parts by weight, the light resistance of the printed image is significantly improved. When the content of the plasticizer is less than 5 parts by weight or more than 40 parts by weight, the effect of improving the light resistance of the printed image cannot be seen. The four plasticizers may be used alone,
Alternatively, two or more thereof may be mixed and used.

In the present invention, the reason why the light resistance of a printed image is remarkably improved by adding a specific amount of a plasticizer having a specific structure to an active energy ray-curable resin has not yet been clarified yet, but Is presumed to be. That is, the dye transferred from the ink sheet is dissolved in the plasticizer contained in the image-receiving layer of the present invention, whereby the colored portion is uniformly distributed in the thickness direction of the image-receiving layer, and the thickness of the dye-distributed portion is increased. Therefore, when the printed image is irradiated with ultraviolet light or the like, only the dye existing in the surface portion of the image receiving layer is decomposed, and the dye existing in the image receiving layer or in the bottom portion is increased. Is likely to remain without being decomposed. On the other hand, in the conventional image-receiving layer formed mainly of synthetic resin, the transferred dye is present only in the surface part of the image-receiving layer and is hardly distributed inside the image-receiving layer or in the bottom part. It is estimated to be. Therefore, when the printed image is irradiated with ultraviolet light, the dye on the surface portion of the receiving layer is decomposed, so that the light resistance of the printed image is considered to be low.

The resin which can be used for forming the image receiving layer of the present invention is a resin having an acryloyl group or a methacryloyl group and cured by an active energy ray. Specifically, (1) (Meth) acrylate compound obtained from polyester polyol, isocyanate, and hydroxyl group-containing (meth) acrylic acid compound,
(2) (meth) acrylate having a rosin residue,
(3) Aliphatic, alicyclic and araliphatic 1 to 6 valent alcohols and (meth) acrylates of polyalkylene glycols, (4) Aliphatic, alicyclic and araliphatic 1 to 6 valent alcohols (Meth) acrylate obtained by adding alkylene oxide to, (5) poly (meth) acryloylalkyl phosphate ester, (6) carboxylic acid, polyol, (meth) acrylic acid reactant, (7) isocyanate, Polyol, (meth) acrylic acid reactant,
(8) A reaction product of an epoxy compound and (meth) acrylic acid,
(9) Epoxy compound, polyol, reaction product of (meth) acrylic acid, and (10) reaction product of melamine and (meth) acrylic acid.

The active energy rays used in the present invention include ionizing radiation such as electron rays, ultraviolet rays and γ rays. Above all, it is preferable to use an electron beam obtained from a curtain beam type electron beam accelerator, which is relatively inexpensive and can obtain a large output, as the active energy ray. In this curtain beam system, the acceleration voltage is 100 to 300.
It is preferable that it is Kv and the absorbed dose is 0.5 to 10 Mrad. The oxygen concentration in the irradiation atmosphere is preferably 500 ppm or less.

In the present invention, the image receiving layer may be blended with a low molecular weight organic compound such as substituted phenol and terpene for the purpose of preventing oxidation, absorbing ultraviolet rays, sensitizing and the like. White pigments generally used for improving the whiteness and opacity of paints, fluorescent dyes for adjusting the color tone of the image receiving layer, and dyes such as blue and violet can be added to the image receiving layer as required. It is convenient to mix the above white pigment, ultraviolet absorber, additive such as crosslinking agent with the image-receiving layer resin which is the main component of the image-receiving layer and apply the mixture.
The UV absorber may be coated as a separate coating layer on or under the image receiving layer.

Further, an ink sheet for heating printing,
A releasing agent may be contained in the image-receiving layer in order to enhance the heat-resistant fusion-bonding property with the image-receiving layer. As such a release agent, waxes such as paraffin and polyethylene wax, metal soap, silicone oil, silicone-based resin, fluorine-based surfactant, fluorine-based resin and the like can be used, and the addition amount thereof is 15% by weight. % Or less is preferable.

When the receiving sheet is running in the printer,
In order to prevent running troubles due to generation of static electricity, an antistatic agent is applied to at least one surface of the receiving sheet, added to the image receiving layer, or contained by a method such as back coating. be able to. Cationic hydrophilic polymers are widely used as antistatic agents.

Examples of the sheet-like support used in the present invention include high-quality paper, coated paper, polyester film, and synthetic paper composed of a uniaxially or biaxially stretched film containing polyolefin and an inorganic pigment as a main component, depending on the application. It is possible to use various plastic films, laminated sheets obtained by combining them, polyolefin resins, and laminated paper obtained by extruding and laminating a resin containing a pigment as a main component. The support used in the present invention preferably has a thickness of 20 to 250 μm and a basis weight of 20 to 250 g / m ² .

Generally, the weight of the image receiving layer is 1 to 20 g /
m ² is preferable, and more preferably 4 to 10 g.
/ M ² . If the image receiving layer is too thin, the density and sensitivity of the image will decrease, and the coating accuracy will decrease, resulting in poor image uniformity. On the other hand, if it is too thick, not only is the effect saturated and uneconomical, but the strength of the image receiving layer is reduced.

[0020]

The present invention will be described in more detail by the following examples. However, the scope of the invention is not limited by these examples.

Synthesis Example 1 of Image Receptor Layer Resin The following dicarboxylic acid component and diol component were heated in a nitrogen atmosphere together with a trace amount of a catalyst of calcium acetate and antimony trioxide, and the temperature was raised to 150 ° C. The temperature was maintained for 1 hour to allow both components to react. Furthermore, while maintaining a vacuum of 0.1 mmHg or less in this reaction system, 250 ° C
Unreacted ethylene glycol was removed while polycondensing for 3 hours to produce a polyester polyol.
To 1 mol of this synthetic polyester polyol, 1 mol of isophorone diisocyanate, 2 mol of 2-hydroxyethyl acrylate, a toluene / MEK mixed solution as a diluent, and a trace amount of 4-methoxyphenol as a polymerization inhibitor were charged. Was gradually heated with stirring, the temperature was raised to 75 ° C, and the reaction was carried out at 75 to 80 ° C for 2 hours. Further, a trace amount of stannous octoate was added as a urethane-forming catalyst to the reaction mixture, and the mixture was reacted at 75 to 80 ° C. for 5 hours to produce an active energy ray-curable resin.

The dicarboxylic acid component Ingredient Quantity terephthalic acid 60 mol% (99.7 g) 40 mol% of isophthalic acid (66.5 g) diol component Ingredient weight ethylene glycol 80 mol% (49.7 g) of neopentyl glycol 30 mol% (34.8 g) 40 mol% of bisphenol A (160.0 g) ethylene oxide adduct

Example 1 A high-quality paper having a basis weight of 150 g / m ² and a polyethylene film of 30 μm laminated on both sides thereof was used as a substrate, and an image receiving layer of a sublimable dye was formed on one side of the substrate. , 5 g of a solid content of the coating composition 1 for the image receiving layer having the following composition
Coating / drying to a coating amount of / m ² and further irradiating the coating layer with an electron beam so as to have an absorbed dose of 3 Mrad to cure the coating layer to form an image receiving layer. A thermal transfer image receiving sheet was prepared.

The image receiving layer coating 1 Preparation Component Parts by weight Synthesis Example 1 the active energy ray curable according resin 100 dicyclohexyl phthalate ester 5 active energy ray-curable silicone 5 (trademark: EBECRYL1360, manufactured by Daicel UCB Co.) Toluene / MEK = 4/1 mixed solution 400

The dye thermal transfer image-receiving sheet obtained as described above is connected to a commercially available sublimation dye transfer color video printer (trademark: VP7100, manufactured by Fuji Film Co., Ltd.) with a color bar generator (trademark: CB11A1, manufactured by Shibazok). Then, a signal of STEP 1 was input to perform printing, and the performance of light resistance of the obtained image was evaluated. To measure the light resistance, the print image was exposed with a xenon fade meter under the conditions of 50 ° C. and 63% RH for 48 hours, and the density of the print image was changed to 1.0 before and after the light resistance test. Change the color difference meter (trademark:
TC1600MC, manufactured by Tokyo Denshoku Co., Ltd.) and a Macbeth densitometer (trademark: No. RD-914, manufactured by Kollmorgen Corp.). The test results are shown in Table 1.

Example 2 An image receiving sheet was prepared and tested in the same manner as in Example 1. However, instead of the paint 1, the paint 2 having the following composition was used. The test results are shown in Table 1. Image-receiving layer coating 2 Preparation Component Parts by weight Synthesis Example 1 of the active energy ray curable resin 100 dicyclohexyl phthalate 25 active energy ray-curable silicone 5 (trademark: EBECRYL1360, Daicel UCB Co., Ltd.) Toluene / MEK = 4/1 mixed solution 400

Example 3 An image receiving sheet was prepared and tested in the same manner as in Example 1. However, instead of the paint 1, the paint 3 having the following composition was used. The test results are shown in Table 1. Image-receiving layer coating 3 Preparation Component Parts by weight Synthesis Example 1 of the active energy ray curable resin 100 dicyclohexyl phthalate 40 active energy ray-curable silicone 5 (trademark: EBECRYL1360, Daicel UCB Co., Ltd.) Toluene / MEK = 4/1 mixed solution 400

Example 4 An image receiving sheet was prepared and tested in the same manner as in Example 1. However, instead of the paint 1, the paint 4 having the following composition was used. The test results are shown in Table 1. Image-receiving layer coating 4 Preparation Component Parts by weight Synthesis Example 1 of the active energy ray curable resin 100 Jiarirufutaru ester 25 active energy ray-curable silicone 5 (trademark: EBECRYL1360, Daicel UCB Co., Ltd.) Toluene / MEK = 4/1 mixed solution 400

Example 5 An image receiving sheet was prepared and tested in the same manner as in Example 1. However, instead of the paint 1, the paint 5 having the following composition was used. The test results are shown in Table 1. Image-receiving layer coating 5 Preparation Component Parts by weight Synthesis Example 1 of the active energy ray curable resin 100 Dioctyl adipate 25 active energy ray-curable silicone 5 (trademark: EBECRYL1360, Daicel UCB Co., Ltd.) Toluene / MEK = 4 / 1 mixed solution 400

Example 6 An image receiving sheet was prepared and tested in the same manner as in Example 1. However, instead of the paint 1, the paint 6 having the following composition was used. The test results are shown in Table 1. Image receiving radiation curable Preparation Component Parts by weight Synthesis Example 1 of layer coating 6 resin 100 triphenyl phosphate 25 active energy ray-curable silicone 5 (trademark: EBECRYL1360, Daicel UCB Co., Ltd.) Toluene / MEK = 4 / 1 mixed solution 400

Comparative Example 1 An image receiving sheet was prepared and tested in the same manner as in Example 1. However, instead of the paint 1, the paint 7 having the following composition was used. The test results are shown in Table 1. The active energy ray curable resin 100 active energy ray-curable silicone 5 Preparation Component Parts by weight Synthesis Example 1 of the image-receiving layer coating material 7 (Trademark: EBECRYL1360, Daicel UCB Co., Ltd.) Toluene / MEK = 4/1 mixture 400

Comparative Example 2 An image receiving sheet was prepared and tested in the same manner as in Example 1. However, instead of the paint 1, the paint 8 having the following composition was used. The test results are shown in Table 1. Image-receiving layer for the active energy ray-curable resin 100 dicyclohexyl phthalate 45 radiation curable silicone 5 Preparation Component Parts by weight Synthesis Example 1 paint 8 (TM: EBECRYL1360, Daicel UCB Co., Ltd.) Toluene / MEK = 4/1 mixed solution 400

Comparative Example 3 An image receiving sheet was prepared and tested in the same manner as in Example 1. However, instead of the coating material 1, the coating material 9 having the following composition was used. The test results are shown in Table 1. Image-receiving layer for the active energy ray-curable resin 100 Jiarirufutaru ester 45 radiation curable silicone 5 Preparation Component Parts by weight Synthesis Example 1 paint 9 (Trademark: EBECRYL1360, Daicel UCB Co., Ltd.) Toluene / MEK = 4/1 mixed solution 400

Comparative Example 4 An image receiving sheet was prepared and tested in the same manner as in Example 1. However, instead of the coating material 1, the coating material 10 having the following composition was used. The test results are shown in Table 1. Image-receiving layer coating 10 Preparation Component Parts by weight Synthesis Example 1 of the active energy ray curable resin 100 triphenyl phosphate 45 active energy ray-curable silicone 5 (trademark: EBECRYL1360, Daicel UCB Co., Ltd.) Toluene / MEK = 4 / 1 mixed solution 400

Comparative Example 5 An image receiving sheet was prepared and tested in the same manner as in Example 1. However, instead of the paint 1, the paint 11 having the following composition was used. The test results are shown in Table 1. Preparation Component Parts by weight Synthesis Example 1 of the active energy ray curable resin 100 Dioctyl phthalate 5 active energy ray-curable silicone 5 of the image-receiving layer coating 11 (Trademark: EBECRYL1360, Daicel UCB Co., Ltd.) Toluene / MEK = 4/1 mixed solution 400

Comparative Example 6 An image receiving sheet was prepared and tested in the same manner as in Example 1. However, instead of the paint 1, the paint 12 having the following composition was used. The test results are shown in Table 1. Image-receiving layer coating 12 Preparation Component Parts by weight Synthesis Example 1 of the active energy ray curable resin 100 Dioctyl phthalate 25 radiation curable silicone 5 (TM: EBECRYL1360, Daicel UCB Co., Ltd.) Toluene / MEK = 4/1 mixed solution 400

Comparative Example 7 An image receiving sheet was prepared and tested in the same manner as in Example 1. However, instead of the paint 1, a paint 13 having the following composition was used. The test results are shown in Table 1. Preparation Component Parts by weight Synthesis Example 1 of the active energy ray curable resin 100 di carbitol phthalate 25 radiation curable silicone 5 of the image-receiving layer coating 13 (Trademark: EBECRYL1360, Daicel UCB Co., Ltd.) Toluene / MEK = 4/1 mixed solution 400

Comparative Example 8 An image receiving sheet was prepared and tested in the same manner as in Example 1. However, instead of the paint 1, the paint 14 having the following composition was used. The test results are shown in Table 1. Image-receiving layer coating 14 Preparation Component Parts by weight Synthesis Example 1 of the active energy ray curable resin 100 methoxyethyl oleate 25 active energy ray-curable silicone 5 (TM: EBECRYL1360, Daicel UCB Co., Ltd.) Toluene / MEK = 4/1 mixed solution 400

Reference Example 1 Sublimation Dye Transfer Color Video Printer (VP710 described above)
0) The same test as in Example 1 was performed on a commercially available exclusive receiving sheet. The results are shown in Table 1.

[0040]

[Table 1]

[0041]

The dye thermal transfer image-receiving sheet of the present invention comprises
By forming an image receiving layer for receiving and fixing a dye image from an active energy ray-curable resin and a plasticizer having a specific structure and a specific compounding amount, the light resistance of the image has been significantly improved. It is practically excellent.

Claims (1)

[Claims] 1. A sheet-like support, and an image-receiving layer which is formed on at least one surface of the support and which receives a dye transferred from an ink sheet by heating.
The image receiving layer contains (1) an active energy ray-curable resin and (2) a plasticizer, and the plasticizer (2) contains dicyclohexyl phthalate ester, diallyl phthalate ester, dioctyl adipate and triphenyl phosphate. The content of the plasticizer (2) is 5 to 40 parts by weight with respect to 100 parts by weight of the active energy ray-curable resin (1). Dye thermal transfer image receiving sheet.