JPH01255590A - Dye sublimation transfer recording sheet - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a dye sublimation transfer recording sheet that forms an image by thermally transferring a sublimation dye. More specifically, the present invention relates to a novel image recording sheet that is capable of thermally transferring a sublimation dye to form a clear, high-density image, has high strength, and has excellent image recording properties. It is.

[Conventional technology]

Recently, high-quality color copy technology using a thermal transfer recording method has made remarkable progress. Dye thermal transfer printers can easily produce high-quality recorded images, and have excellent characteristics such as being highly reliable and relatively inexpensive. There is.

In such a dye transfer method, the amount of dye transferred from the ink sheet can be continuously controlled by controlling the amount of heat applied from the thermal head. The sublimation temperature of the dye is Ts1 The peak temperature of the dye layer is T
2. When the heating time is t3, the following equation exists between the image density and the heating time.

D=[t, (TP-T,)]l/2+Dp (Dp represents the color density of paper) Therefore, 3 colors (Y, M, C) or 4 colors (Y.

From the M, C, and B) ink sheets, each dye is transferred in an amount determined by the heating time. In other words, images of different hues are continuously formed according to changes in each dye transfer scene, and the density gradation can be controlled.

In order to obtain a high-quality recorded image, it is required that the dye to be transferred has a high recording density (and high image uniformity). A recording sheet has been proposed in which an undercoat layer having the following structure is provided below a sublimable dye-receiving layer.

For example, JP-A-61-248791 discloses a recording sheet in which a coating layer containing a pigment having an average oil absorption of 35 to 140 d/g and a particle size of 2 to 20 mm is formed on a support. ing.

[Problem to be solved by the invention]

Up until now, the recording sheets used in sublimation transfer printers have been printed on paper made mainly of natural pulp, films made mainly of polyolefin resin, or synthetic paper, either directly or through an undercoat layer. , a dye image-receiving layer was provided. However, images formed on recording sheets using a polyolefin resin synthetic paper base are full-color;
Although the image quality is high, there is a disadvantage that the recording sheet is deformed due to heating during recording. In addition, recording sheets using natural pulp paper have disadvantages such as poor image uniformity and low image density, so that a fully satisfactory recording sheet has not been obtained.

An object of the present invention is to provide a dye sublimation transfer recording sheet that can form clear, high-density images with high uniformity, is relatively inexpensive, and has excellent practical recording suitability.

Another object of the present invention is to have good processability and excellent writability,
To provide a sublimation transfer recording sheet that is free from deformation such as curling due to heat during recording and has an excellent natural feel.

[Means to solve the problem]

In order to solve the above-mentioned drawbacks of the prior art, the inventors of the present invention have made various studies, and as a result, they have applied silica, which is a type of highly oil-absorbing inorganic pigment, to the surface of a support together with a binder resin material. The present invention has been completed based on the discovery that by forming an undercoat layer, the image receptivity of the sublimation dye image-receiving layer provided thereon can be significantly improved.

That is, the dye sublimation transfer recording sheet of the present invention includes a sheet-like support, and at least one side of the support,
and 30-80% by weight silica and 20-70% by weight
The dye image-receiving layer is characterized by comprising an undercoat layer containing as a main component a mixture with a binder resin material, and a dye image-receiving layer formed on the undercoat layer.

The recording sheet of the present invention has a high density of the dye transferred to its surface, that is, an image density, and has good image uniformity.Therefore, it provides a high-quality image, and at the same time, it is free from deformations such as curling caused by heat during recording. Furthermore, it has good processing suitability and can form an image record with an excellent natural feel.

The silica used in the present invention is a rubber fuel, a matting agent,
It may be either general hydrophilic silica that can be used for papermaking fuel or the like, lipophilic silica surface-treated with a silane coupling agent, paraffin, etc., or a mixture of two or more of these. The silica is preferably fine particles with a particle size of 1 to 10 μm. In the undercoat layer upper component mixture,
The white pigment has a proportion of 30 to 80% by weight, preferably 40 to 80% by weight.
It is contained in a proportion of 80% by weight. When the silica content is lower than 30% by weight, the image improving effect of the undercoat layer becomes insufficient, and when it exceeds 80% by weight, the mechanical strength of the resulting undercoat layer becomes insufficient.

In the undercoat layer, white inorganic pigments and/or organic pigments used for general coated paper can also be used in combination with pigments other than silica. As such white inorganic pigments, talc, light and heavy calcium carbonate, calcined kaolin, kaolin, zeolite, satin white, etc. are used. As the white organic pigment, a polymer material having a glass transition point higher than room temperature, such as urea-formalin resin, polystyrene, or polymethyl methacrylate, is used.

The amount of such a white pigment used in combination is preferably 30% or less based on the weight of the silica. The combined white pigment may be mixed with the main component mixture, or a silica-binder resin material undercoat layer may be applied on the coating layer of the combined white pigment-binder resin material mixture. .

The main components of the binder resin material used in the undercoat layer are:
In order to improve the adhesion to the pigment particles, relatively soft SBR latex with a glass transition point of 0°C or lower,
Acrylic ester copolymers and the like can be used alone or in combination with other adhesives.

Other binder resin materials may contain various water-soluble, solvent-soluble, or water-dispersible adhesives, and examples of such adhesive components include starch, polyvinyl alcohol, etc. .

The content of the binder resin material in the primer component mixture is 20
-70% by weight, preferably 35-50% by weight.

If this content exceeds 70% by weight, the image improvement effect of the undercoat layer will be insufficient, and the resolution of the image will decrease. If the content is less than 20% by weight, the power of the obtained undercoat layer will be insufficient. This results in insufficient mechanical strength. The content of the main component of the silica-binder resin material mixture in the undercoat layer is preferably at least 80% by weight.

-For boat fishing, the weight of the undercoat layer is 10 to 80 g/m'
It is preferable that it is, and it is more preferable that it is 10-40 g/m'. If the undercoat layer is thin, the density and sensitivity of the resulting image will decrease, and the uniformity of the image will deteriorate. Furthermore, if the undercoat layer is too thick, the effect will be saturated and this will not only be uneconomical but also cause the disadvantage that the strength of the undercoat layer will be reduced.

As the sheet-like support used for the recording sheet of the present invention, in addition to paper, synthetic paper and various plastic films can be used depending on the purpose. High-quality paper is preferred because it is inexpensive and has excellent heat resistance.

There is no particular limitation on the thickness of the sheet-like support, but it is generally 10 to 200 J-, and the basis weight is 10 to 200 g.
/ml is preferred.

Conventionally, dyes used for dyeing polyester fibers used in the textile industry have been used as dyes for sublimation dye transfer printers. However, with existing dyes, those with low sublimation temperatures have poor fixing properties and light resistance, while those with good fixing properties and light resistance have high sublimation temperatures and require large amounts of energy for transfer. was there. For this reason, special sublimation dyes are currently being developed for sublimation dye transfer.

The image-receiving layer to which such dyes are dyed is made of a resin base such as polyester resin mixed with a sensitizer, a release agent, a white pigment, etc., so that the sublimation dye is not easily dyed. ing.

Generally the image-receiving layer has a weight of 1 to 30 g/m';
It is formed to a thickness of 30J-.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples. In addition, in the examples, "parts" indicate parts by weight of solid content,
The sheet before coating is referred to as a support, the sheet coated with an undercoat layer is referred to as a recording sheet substrate, and the sheet further coated with a receiving layer for a sublimation dye image is referred to as a recording sheet.

Example 1 Composition of undercoat paint-1 Pigment Nijirica (P78A, manufactured by Mizusawa Chemical Co., Ltd.) 100 parts Binder resin material: Styrene-butadiene copolymer (JSRO64)
2. 50 parts (manufactured by Japan Synthetic Rubber Co., Ltd.) Starch (Tamago Ace B1, manufactured by Tamago Constarch Co., Ltd.) 10 parts Dispersant: 1.5 parts of sodium polyacrylate (Aron T40, manufactured by Toagosei Kagaku Co., Ltd.) % aqueous solution as primer paint-1
This was prepared and coated on one side of a support made of high-quality paper (basis weight 64 g/m") at a solid content of 30 g/m", dried, and smoothed using a supercalender. provided. A recording sheet base material was obtained in which the Bekk smoothness of the surface of the undercoat layer was 1000 seconds and the smoothness of the opposite surface was 50 seconds. On the undercoat layer of this sheet base, polyester (Vylon 200, manufactured by Toyobo Co., Ltd.) was coated in an amount of 10 g/m'' to form a sublimation dye image-receiving layer to obtain a recording sheet. Table 1 shows the results of printing on the sheet using a commercially available sublimation transfer link (manufactured by Hitachi, VY-50) and evaluating the quality.

However, the evaluation items are color density, uniformity, color clarity, thermal curl, and strength of the coating layer.

The results of these sublimation transfer recording sheets were evaluated on a five-level scale. (5... Excellent, 4... Good, 3... Fair, 2...
...fairly poor, 1...poor) Color density was measured using a Macbeth densitometer.

The clarity of color development, uniformity of the image, and thermal curl after printing were evaluated by sensory evaluation, and the surface strength was evaluated by the degree to which the coating layer and receiving layer were removed by peeling off the cellophane tape.

Example 2 Undercoat paint-2 composition Pigment Nisilica (P78^ manufactured by Mizusawa Kagaku Co., Ltd.) 80 parts Baked Ray (Ansilex Engelhardt Co., Ltd.) 20
Binder resin material Niacryl styrene copolymer (Movinyl 731 manufactured by Hoechst Gosei Co., Ltd.) 501 polyvinyl alcohol (NL05 manufactured by Nippon Gosei Kagaku Co., Ltd.) 10 parts Dispersant: Sodium polyacrylate (Aron T40 manufactured by Toagosei Kagaku Co., Ltd.) 1. 5 parts Paint-2 with a concentration of 40% by weight was prepared from the mixture having the above composition, and this was coated on the same high-quality paper as described in Example 1 at a solid content of 30 g/m', and dried. This was then smoothed using a supercalender. A recording sheet base material was obtained in which the Bekk smoothness of the surface of the undercoat layer was 2000 seconds and the smoothness of the opposite surface was 50 seconds. Using this base material, the same treatment as described in Example 1 was performed. Table 1 shows the evaluation results of the printing quality of the obtained recording sheets.

Below is the margin Example 3 Undercoat paint - 3 Composition Pigment: 100 parts of surface treated silica (P2S5 manufactured by Mizusawa Chemical Co., Ltd.) Binder material Niacrylic ester copolymer (Paraloid B82 Rohm & Haas) 50 parts From the mixture of the above composition A 20% by weight toluene solution was prepared and used as undercoat paint-3. This paint-3 was applied to one side of YUPO FPG 80 (egg oiled synthetic paper) forming the support at a solid content of 30 g/m'', dried, and smoothed using a super calender. A recording sheet base material was obtained in which the Bekk smoothness of the surface of the undercoat layer was 15,000 seconds and the smoothness of the opposite surface was 500 seconds. Using this base material, the same treatment as in Example 1 was performed. Table 1 shows the evaluation results of the printing quality of the obtained recording sheets.

Example 4 Undercoat paint-4 composition Pigment: Kaolin (HG clay, manufactured by Engelhardt Co., Ltd.) 100N Binder resin material: Styrene-butadiene copolymer (JSRO642, manufactured by Nippon Gosei Rubber Co., Ltd.) 50 parts polyvinyl alcohol (NL05, manufactured by Nippon Gosei Kagaku Co., Ltd.) 10 parts Dispersant: Sodium polyacrylate (Aron T40 manufactured by Toagosei Kagaku Co., Ltd.) 1 part A coating layer of Paint-4 was provided in an amount of 20 g/m'' on the same support as described in Example 1. , and furthermore, the paint-
After applying the undercoat layer of 1 in an amount of 20 g/m'', this was smoothed with a super calendar, and the coated surface had a smoothness of 350 seconds, and the opposite side had a smoothness of 50 seconds. A base material was obtained.

Using this base material, the same treatment as described in Example 1 was performed. Table 1 shows the evaluation results of the printing quality of the obtained recording sheets.

Comparative Example 1 The same treatment as in Example 1 was performed. However, a 40% by weight paint-4 was prepared, a coating layer of 30 g/m'' was applied to the support of Example 1, and smoothing treatment was performed using a super calender, and the coated surface had a solid smoothness of 4000 seconds and a coating layer of 30 g/m''. A recording sheet base material with a surface smoothness of 50 seconds was obtained.The results are shown in Table 1.

Comparative Example 2 The same treatment as in Example 1 was performed. However, the recording sheet base material is YUPO FPG15, a multilayered synthetic paper containing inorganic pigments.
0 (thickness 150J-, egg oil synthetic paper) was used. The results are shown in Table 1.

Margin Table 1 below [Effects of the Invention] The sublimation transfer recording sheet of the present invention has good image resolution and uniformity by forming an undercoat layer containing silica under the dye image-receiving layer. It exhibits excellent performance, with high color density, little thermal curling after printing, and excellent image clarity and natural appearance. The present invention has made possible sublimation dye transfer prints that exhibit a high degree of resolution not previously available.

Claims (1)

[Claims] 1. A sheet-like support; 30 to 80% by weight of silica formed on at least one side of the support; 2.
A dye sublimation transfer recording sheet comprising an undercoat layer containing as a main component a mixture with 0 to 70% by weight of a binder resin material, and a dye image-receiving layer formed on the undercoat layer.