JPH04275194A - Thermal transfer recording image receiving sheet - Google Patents

Abstract

PURPOSE:To provide a thermal transfer recording image receiving sheet capable of performing high density printing and obtaining a recording image of high image quality. CONSTITUTION:An intermediate layer consisting of a resin cured by the irradiation with ultraviolet rays or electron beam and hollow particles is provided between a base material sheet and an image receiving layer.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image-receiving sheet for thermal transfer recording. More specifically, the present invention relates to an image-receiving sheet for thermal transfer recording that allows recording images with high print density and good quality to be obtained.

0002

[Prior Art] Thermal transfer recording method involves laminating a thermal transfer sheet (ink film) and a medium (image receiving sheet) having an image receiving layer that can be recorded by heating using this sheet, and applying dye by heating using a thermal head. This is a recording method in which data is transferred to the medium side. This recording method has good gradation reproducibility of recorded images, so it is used in printers, facsimile machines, video printers, etc. The image-receiving sheet used in this recording method is generally one in which an intermediate layer having heat insulating and cushioning properties is provided between the base sheet and the image-receiving layer in order to obtain a good recorded image. Thermal insulation properties,
A method for producing an image-receiving sheet for thermal transfer recording having an intermediate layer with cushioning properties involves coating a base material with a rubber-elastic polymer material containing expandable microcapsules, hollow particles, and porous substances. There are known ways to do this. However, when the image-receiving layer paint is organic solvent-based, there is a problem that the image-receiving layer paint penetrates into the polymeric material of the intermediate layer, making it impossible to obtain good image quality. When an organic solvent-based paint is used as the image-receiving layer paint, as a method for preventing the paint from penetrating into the polymeric material of the intermediate layer, for example, Japanese Patent Laid-Open No. 64-27
No. 996 describes a method of providing an intermediate layer made of hollow particles and an organic solvent-resistant polymeric material, or a method of coating an organic solvent-resistant polymeric material on the intermediate layer. However, in the former case, when a hydrophilic polymer such as polyvinyl alcohol is used, the intermediate layer generally becomes brittle, making it impossible to impart desired properties, and in the latter case, there are problems such as an increase in the number of coating steps.

On the other hand, as a method for forming a layer having heat insulating properties and cushioning properties, for example, Japanese Patent Application Laid-Open No. 59-3313
As described in No. 3, a method in which a coating consisting of an ultraviolet curable unsaturated prepolymer, a polymerization monomer, a photopolymerization initiator, and a foaming agent is applied onto a base material, and the coating is cured and foamed at the same time by ultraviolet irradiation. is proposed. However, the method of obtaining an intermediate layer with heat insulating and cushioning properties using a foaming agent or expansion agent normally contained in electron beam or ultraviolet curable paints is difficult to obtain after heat treatment due to uneven foaming, coating unevenness, etc. The unevenness on the surface of the coating layer significantly reduces the highly smooth surface originally obtained by electron beam or ultraviolet curing, resulting in poor surface properties even after the image-receiving layer is coated.
Unable to obtain good image quality.

0004

[Problems to be Solved by the Invention] The present invention solves the above-mentioned problems of conventional image-receiving sheets for thermal transfer recording, and provides an image-receiving sheet for thermal transfer recording that has excellent surface smoothness, high sensitivity, and can produce images of good quality. It provides:

[0005]

[Means for Solving the Problems] As a result of intensive studies to achieve the above object, the present inventors found that when an intermediate layer is provided on a base material such as paper, ultraviolet rays or electron beams mixed with hollow particles can be used. By providing an intermediate layer using a resin that hardens by irradiation, it is possible to obtain an intermediate layer that is highly smooth, has excellent organic solvent resistance, has heat insulation properties, cushioning properties, etc., and by providing an image receiving layer on top of this, a high concentration The present invention was completed based on the discovery that it is possible to produce an image-receiving sheet for thermal transfer recording that allows printing and provides a good quality recorded image. That is, the image-receiving sheet for thermal transfer recording of the present invention is a thermal transfer recording image-receiving sheet in which an intermediate layer and an image-receiving layer are sequentially provided on a base material, and the intermediate layer is made of a resin that is cured by ultraviolet rays or electron beam irradiation and contains hollow particles. It is characterized by:

As the compound that is cured by ultraviolet rays or electron beam irradiation used in the intermediate layer of the present invention, acrylate or methacrylate monomers or oligomers having one or more ethylenically unsaturated bonds can be used. Although not particularly limited, examples of monofunctional monomers include N-vinylpyrrolidone, acrylonitrile or its derivatives, styrene or its derivatives, amide group-containing monomers such as acrylamide, and fatty acid acrylates or methacrylates such as lauryl (meth)acrylate. , benzyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, tetrahydrofurfuryl acrylate, phenoxyethyl acrylate, nonylphenoxyethyl acrylate, ε-caprolactone adduct acrylate, butoxy ethyl (meth)acrylate,
2-Hydroxy-3-phenoxypropyl acrylate, cyclohexyl (meth)acrylate, N,N-dimethylamino (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, 3-phenoxypropyl acrylate, 2-methoxyethyl ( Examples include acrylates or methacrylates such as meth)acrylate, and monomers having two or more ethylenically unsaturated bonds include hexanediol diacrylate,
Neobentyl glycol diacrylate, diethylene glycol diacrylate, tripropylene glycol diacrylate, tetraethylene glycol diacrylate, tricyclodecane dimethylol diacrylate, trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, ethylene oxide modified bisphenol A diacrylate Examples include acrylate. These compounds having one or more ethylenically unsaturated bonds may be used alone or in combination of two or more, if necessary. Blending one or more acrylate or methacrylate oligomers having two or more ethylenically unsaturated bonds in the molecule, such as urethane acrylate oligomers, butadiene-modified acrylate oligomers, etc., to the above ethylenically unsaturated monomer composition makes it possible to form an intermediate layer. It is effective in terms of curability, and it is possible to obtain an intermediate layer that is highly smooth, has excellent organic solvent resistance, and has no surface tack and is rich in flexibility. When the above compound is cured using ultraviolet rays, a sensitizer such as benzoin ethyl ether, benzophenone, benzophenone alkyl ether, etc. is blended as necessary. A polymer soluble in these compositions may be added to the composition of the present invention that is cured by ultraviolet rays or electron beam irradiation, but if the amount of the polymer is too large, the curability of the coating film will decrease; Not preferred from the viewpoint of organic solvent resistance.

The hollow particles used in the intermediate layer of the present invention are not particularly limited, but include, for example, the following materials. (1) Manufactured by Nippon Paint, trademark: Nippe Microgel
MBB-1000, average particle size 10 μm, porosity 0.
37cc/g (2) Made by Japan Synthetic Rubber, trademark: JSR-SX863 (A
), average particle diameter 0.4 μm, inner pore diameter/particle diameter ratio 0.66 (3) Manufactured by Nipfilite Co., Ltd., trademark: Expancel DE2
0, average particle diameter 20 μm, density 0.05 g/cm3
The above particles have a diameter of 0.1 to 100 μm, preferably 0.2 μm.
It is necessary to have a particle size of about 50 μm, and 0
．． If it is less than 1 μm, the insulation and cushioning properties are insufficient, and if it exceeds 100 μm, a smooth intermediate layer surface cannot be obtained. Further, although the higher the porosity is, the more preferable it is, it is possible to obtain sufficient heat insulation and cushioning properties even with the hollow particles described above. Furthermore, it is also possible to use porous substances instead of hollow particles. The content of the hollow particles is 0.5 to 100 parts by weight, preferably 1 to 70 parts by weight, per 100 parts by weight of the ultraviolet or electron beam curable resin. However, if the amount exceeds 100 parts by weight, the surface properties will deteriorate and it will be difficult to obtain the desired results.

As described above, the intermediate layer of the present invention is composed of a composition mainly composed of hollow particles and acrylate or methacrylate monomers or oligomers, but if necessary, surface properties, organic solvent resistance, Colored dyes, colored pigments, within the range that does not impair insulation and cushioning properties.
There is no problem in adding auxiliary agents such as lubricants and antistatic agents, and in addition, calcium carbonate, titanium dioxide, zinc oxide, kaolinite clay, talc, aluminum hydroxide, magnesium oxide, diatomaceous earth, satin white,
It is also possible to incorporate white pigments such as barium sulfate, basic calcium carbonate, silicon dioxide, and aluminum oxide.

After the prepared composition is applied onto a substrate, it is instantly cured by irradiation with ultraviolet rays or electron beams. In this case, the coating amount is 5 to 100 g/m2, preferably 10 to 7
It is necessary to keep it within the range of 0g/m2, and 5g/m2.
If it is less than 2, a highly smooth surface and sufficient heat insulation cannot be obtained, and if it exceeds 100 g/m2, an intermediate layer with sufficient hardening inside the paint cannot be obtained. All normal coating methods such as roll coater, Meyer bar, slit die coater, and curtain coater can be used to apply the paint. Coating is also possible.

The base material constituting the image receiving sheet includes paper,
Synthetic paper, synthetic resin film, or a laminated sheet of a combination thereof can be used, but a surface-treated base material can also be used to further improve adhesiveness and barrier properties. The thickness of such a base material is not particularly limited, but from the viewpoint of strength, workability, etc., it is preferably 20 to 250 μm, and the basis weight is 20 to 250 g/
Preferably, it is m2.

[0011]

EXAMPLES The present invention will be explained in more detail with reference to Examples below, but the invention is not limited thereto. Example 1 Hollow particles (J
After adding 60 parts by weight of SR Co., Ltd., trademark: JSR-SX863 (A)) and mixing and dispersing with a ball mill, the basis weight was 127.9 g/
It was coated onto 40 g/m2 of cast coated paper (manufactured by Oji Paper Co., Ltd., trademark: OK Enamel Coat) using an applicator bar so that the coating amount was 40 g/m2. Next, the coating layer was irradiated with an electron beam irradiation device with an accelerating voltage of 175 KeV to give an absorbed dose of 6M.
An electron beam was irradiated to obtain a tack-free and fully cured intermediate layer. Further, on this intermediate layer, a composition for forming an image receiving layer having the following composition was applied in a coating amount of 6 g/m2 after drying.
After coating, an image-receiving layer was formed by drying and curing to obtain an image-receiving sheet for thermal transfer recording.

Image-receiving layer forming composition Polyester resin (manufactured by Toyobo, trademark: Vylon200)
100g Crosslinking agent: trifunctional isocyanate (manufactured by Nippon Urethane Kogyo, trademark: Coronate L) 5g silicone resin (manufactured by Toray Silicone, trademark: SH347
6) 3g toluene

200g methyl ethyl ketone

200 g of the image-receiving sheet and transfer sheet obtained above were combined and printed using a thermal transfer printer, and the resulting recorded material was designated as recorded material 1. The transfer sheet used was a commercially available UPC5010A manufactured by Sony Corporation, and the thermal transfer printer used was a commercially available UP-5000 manufactured by Sony Corporation.

Example 2 90 parts by weight of 2-hydroxy-3-phenoxypropyl acrylate and 10 parts by weight of urethane acrylate oligomer having a molecular weight of 1200 and three ethylenically unsaturated bonds (manufactured by Arakawa Chemical, trademark: Beamset 550B) were blended. 40 parts by weight of hollow particles (manufactured by Rohm and Haas Co., Ltd., trademark: Low Bake OP84-J) were added to the paint, mixed and dispersed using a Cowles homomixer, and coated paper with a basis weight of 104.7 g/m2 (manufactured by Oji Paper Co., Ltd., trademark: OK Coat) was coated using an applicator bar so that the coating amount was 30 g/m2. Next, the coating layer was irradiated with an electron beam using an electron beam irradiation device with an accelerating voltage of 175 KeV so that the absorbed dose was 4 Mrad to obtain a fully cured intermediate layer without tack. An image receiving layer was formed on this intermediate layer in the same manner as in Example 1 to produce an image receiving sheet for thermal transfer recording. Using this image-receiving sheet, a recorded matter was obtained in the same manner as in Example 1, and a recorded matter 2 was obtained.
And so.

Example 3 81 parts by weight of phenoxydiethylene glycol acrylate, 15 parts by weight of polybutadiene acrylate oligomer (manufactured by Nippon Soda Co., Ltd., trademark: TEA1000) having a molecular weight of 2000 and having two ethylenically unsaturated bonds, and benzophenone and dimethyl as sensitizers. 50 parts by weight of hollow particles (manufactured by Nippon Paint Co., Ltd., trademark: NIPPE MICRO GEL MBB-1000) were added to paints each containing 2 parts by weight of aminoethanol, mixed and dispersed in a ball mill, and the basis weight was 127.
A coating weight of 30 g/m was applied using an applicator bar on 9 g/m2 coated paper (manufactured by Oji Paper Co., Ltd., trademark: OK Coat).
It was coated so that it became 2. Then apply 80W/cm to the coating layer.
Irradiate with a high-pressure mercury lamp from a height of 15 cm for 1 second,
A fully cured coating layer without tack was obtained. Thereafter, an image-receiving sheet for thermal transfer recording was produced in the same manner as in Example 1, and then a recorded matter was obtained, which was designated as recorded matter 3.

Comparative Example 1 An image-receiving sheet for thermal transfer recording was prepared in the same manner as in Example 1, except that the image-receiving layer was coated directly on the base material without providing an intermediate layer, and the recorded matter was further coated in the same manner as in Example 1. This was recorded as Recorded Material 4. Comparative Example 2 A receiving sheet for thermal transfer recording was produced in the same manner as in Example 2, except that an intermediate layer consisting only of a resin containing no hollow particles was provided, and a recorded matter was further obtained. And so. Comparative Example 3 A receptor sheet for thermal transfer recording was produced in the same manner as in Example 3, except that the image-receiving layer was coated directly on the base material without providing an intermediate layer, and further recorded matter was obtained. This is recorded as record 6.

Regarding the above recorded materials 1 to 6, the maximum color density was measured and the image quality of the recorded images was evaluated by the method shown below. The results are shown in Table 1. (1) Maximum color density Macbeth densitometer (Kollmorgen Corp.
RD-914), and was determined as the average value of five measurements. (2) Evaluation of image quality Regarding each of the five recorded materials, the sharpness and contrast were visually judged and evaluated in three stages: ◯: good, △: slightly poor, and ×: poor.

[0017]

[Table 1]

[0018]

[Effects of the Invention] As is clear from Table 1, the image-receiving sheet for thermal transfer recording of the present invention provides recorded images with high print density and good quality, and is extremely useful in practice. be.

Claims (1)

[Claims] 1. An image-receiving sheet for thermal transfer recording in which an intermediate layer and an image-receiving layer are sequentially provided on a base material, characterized in that the intermediate layer is made of a resin that is cured by ultraviolet rays or electron beam irradiation and contains hollow particles. Image receiving sheet for thermal transfer recording.