JP2758411B2 - Polyester resin-based image receptor for thermal transfer - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image receiver as a transfer object for a thermal transfer medium using a sublimable dye.

<Related Art> An image receiving body for forming a transfer image using a heat-sensitive transfer medium containing a sublimable dye in a heat-sensitive transfer layer has good dyeing properties, light resistance, chemical resistance, and friction resistance. (Resin film peeling) during printing of heat-sensitive and heat-sensitive transfer media and image receiving body
Prevention properties are required. Further, in recent years, when imaging information from video signals and the like, as the application of thermal transfer media using sublimable dyes has rapidly expanded, the storability of the image, especially plasticizer resistance and transfer resistance, Is required to be improved.

In order to transfer and develop the sublimable dye of the thermal transfer medium to the image receiving member satisfactorily, it is necessary that the resin on the image receiving member side has good dyeability to the sublimable dye.

The lower the softening point and the glass transition point, the better the dyeing properties of the resin. However, such a resin having good dyeing properties is easily fused with the resin holding the sublimable dye of the thermal transfer medium at the time of thermal transfer to cause blocking, and the sublimable dye once dyed re-sublimates. It is disadvantageous in that the image is easily deteriorated. The blocking phenomenon during thermal transfer is also related to the amount of resin applied to the transfer medium,
In particular, in order to prevent blocking from the dye transfer medium side to the image receiving body side, it is necessary to devise some means in the resin layer of the image receiving body. As an example, it is conceivable to cure the surface resin layer of the image receiving body to increase the heat resistance. However, in this case, the sublimable dye on the transfer medium side is not easily dyed on the image receiving side, and the image density is reduced.

It is also conceivable to mix additives such as silicone oil into the resin layer of the image receiving body or apply silicone oil or the like to the resin surface of the image receiving body to activate the image receiving body surface. It is viscous, easily stained, and has problems in fingerprint resistance. As described above, there is a reciprocal relationship between the good dyeability of the sublimable dye from the transfer medium to the image receptor side and the storage stability after dyeing, and there is no specific solution at present. .

<Problems to be Solved by the Invention> The present invention has been made in view of the above circumstances, and does not cause resin transfer from a thermal transfer medium containing a sublimable dye in a thermal transfer layer, and has a high density. An object of the present invention is to provide a heat-sensitive transfer image receiving member capable of forming a dye transfer image, and having excellent fingerprint resistance and storage stability.

<Means for Solving the Problems> As shown in FIG.
At least a dyeing image receiving layer (2) having good dyeing properties for a sublimable dye is formed on a substrate (1) made of paper, a plastic film, an inorganic sheet or the like.

In the dyeing image receiving layer (2), first, the polyester resin which is the main component is composed of (1) an aromatic dicarboxylic acid of 90 to 100 mol%.
And (2) at least one of an ethylene oxide adduct of bisphenol A and a propylene oxide adduct of bisphenol A represented by the following general formula: The adduct is a bimolecular adduct (m = n = 1) 30 to 97.5
Mol%, multi-molecule adduct (m, n ≧ 1) 0 to 2.5 mol%,
And a diol component comprising 70 to 0 mol% of an aliphatic dialcohol having 2 to 6 carbon atoms.

<General formula> (However, in the formula, R ₁ and R ₂ represent hydrogen or a methyl group, and m, n
Represents an integer of 1 or more. ) Tensile breaking strength 300Kg / cm ²
(ASTM ・ D ・ 638) or higher, tensile elongation at break 20% (ASTM ・ D ・ 638)
・ 638) A dye-permeable release agent composed mainly of a polyester resin having the above-mentioned properties and made of an addition-reaction or condensation-reaction-type curable silicone resin, or a silicone resin, silicone oil, fluorine resin, etc. It is composed of a composition containing a release agent. Dyeing image receiving layer (2)
In such a configuration, there is no resin transfer from the thermal transfer medium side including the sublimable dye in the transfer layer to the image receiving side at the time of thermal transfer, and peeling of the thermal transfer medium and the image receiving body after thermal transfer. Smoothly performed, and while the dyeing resin has a high softening point and a high glass transition point, obtains the same degree of dyeing properties as a good dyeing resin having a low softening point and a low glass transition point. It is to be able to do.

Such a dyeing image receiving layer (2) is, for example, an addition-reaction or condensation-reaction-type curable silicone resin with respect to 100 parts by weight of a polyester resin having the above characteristics dissolved in 2-butanone or a mixed solvent of toluene-2-butanone. (1 to 2 parts (solid content) of catalyst per 100 parts by weight of silicone resin solid content)
Of about 5 to 15 parts by weight, and may be formed to a thickness of 4 to 6 μm.

An inorganic filler fine powder may be added to the dyeing image receiving layer (2).

Table 1 shows the improvement in anti-blocking properties, dyeability, and storage stability when addition-reaction or condensation-reaction-type curable silicone resins are added to thermoplastic polyester resins having different tensile rupture strengths and tensile rupture elongations. This is shown in comparison with the case where no silicone resin is added.

As can be understood from Table 1, even if the addition reaction or condensation reaction type silicone resin is contained in the thermoplastic polyester resin, the polyester resin has the structure described in the claims, and the polyester resin has a tensile strength. Breaking strength is 30
0kg / cm ² (ASTM ・ D ・ 638) or more, tensile elongation at break 20%
(ASTM · D · 638) or more, the binder resin in the heat-sensitive transfer layer may migrate or fuse to the dyeing image receiving layer (2) at the time of heat transfer due to the peeling action of the silicone resin. And the dye alone can be efficiently transferred into the dye receiving layer (2), and the density of the transferred image, the storage stability after dye transfer, especially the light fastness due to the selection of the dyeing resin having the specific physical properties. In addition, it is possible to further improve the thermoplasticity.

Production Example A of Polyester Resin 60 moles of terephthalic acid, 40 moles of isophthalic acid, 50 moles of an ethylene oxide bimolecular adduct of bisphenol A and 90 moles of ethylene glycol were supplied to an esterification reactor, and the esterification reaction was carried out at 250 ° C. for 5 hours. After removing the theoretical amount of water to the outside of the reaction system, 0.03 mol of germanium dioxide was added, and a polycondensation reaction was carried out at 270 ° C. under a reduced pressure of 0.5 mmHg. (Measured at 20 ° C. in water) to prepare a polyester resin of 0.70.

The tensile strength at break of the polyester resin was 350 kg / cm ² , and the tensile elongation at break was 25%.

Polyester resin production example B In the same manner as polyester resin production example A, except that in addition to the raw materials of production example A, a polymolecular ethylene oxide adduct of bisphenol A (number-average molecular weight ≒ 2000, m + n ≒ 4
0) Esterification and polycondensation were carried out using 0.75 mol to prepare a polyester resin having an intrinsic viscosity of 0.71.

The polyester resin had a tensile strength at break of 320 kg / cm ^{2 and a} tensile elongation at break of 95%.

Example 1 10 parts by weight of a 20% by weight polyester resin solution of Production Example A dissolved in an aromatic or ketone-based solvent on a synthetic paper substrate surface of a polypropylene-based resin and a curable silicone resin X-62
-2112 (manufactured by Shin-Etsu Silicone Co., Ltd.) in a 62% by weight toluene solution (CAT PL-8 (manufactured by Shin-Etsu Silicone Co., Ltd.)) was added to X-62.
-2112 10 parts by weight per 100 parts by weight) and 10 parts by weight of the mixture were applied and dried at a high temperature of 100 ° C. or more for at least 20 seconds to form a dyeing image receiving layer having a thickness of 5 μm. An image receptor for thermal transfer was obtained. Then, as a result of printing a thermal transfer medium containing a sublimable dye with a thermal printer or the like,
Image density 13 or more with 1mJ / dot energy (solid area)
Good image was obtained, and a mending tape (manufactured by Scotch) was stuck on the image and stored at 40 ° C and 90% RH for 48 hours. Dye transfer to the mending tape was observed. I couldn't.

<Example 2> Same as Example 1 except that the polyester resin of Production Example A was replaced with 8 parts of the polyester resin of Production Example A to produce Production Example B.
A polyester resin solution was prepared by using 2 parts of the polyester resin in combination, and an image receiving body for thermal transfer was obtained in the same manner as in Example 1. As a result of printing in the same manner as in Example 1, a good image was obtained. The storage stability of the image was also good.

<Effects of the Invention> The image receiving body of the present invention having the above-described structure can form a high-density dye transfer image without causing resin transfer from a thermal transfer medium, and has excellent fingerprint resistance and storage stability. ing.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic structural view of an image receiving body of the present invention. (1) ... substrate, (2) ... dyeing image receiving layer

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-74693 (JP, A) JP-A-2-34392 (JP, A) JP-A-62-152897 (JP, A) JP-A 64-64 30793 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) B41M 5/38-5/40

Claims (1)

(57) [Claims] 1. A heat-sensitive transfer image receiving body comprising at least a dyeing image receiving layer having a dyeing property for a sublimable dye on a substrate made of paper, plastic, or the like, wherein a main body of the dyeing image receiving layer is provided. (1) 90 to 100 mol% of aromatic dicarboxylic acid and non-aromatic dicarboxylic acid 1
(2) at least one of an ethylene oxide adduct or a propylene oxide adduct of bisphenol A represented by the following general formula, wherein the adduct comprises 2 molecules Addition (m
= N = 1) 30 to 97.5 mol%, multi-molecular adduct (m, n ≧
1) a diol component comprising 0 to 2.5 mol% and an aliphatic dialcohol having 2 to 6 carbon atoms and 70 to 0 mol%, and the dyeing image receiving layer contains a release agent. Polyester resin-based thermal transfer image receiver. General formula (In the formula, R ₁ and R ₂ are either hydrogen or a methyl group, and m and n are each an integer of 1 or more.)