JPH091942A - Sublimation type transfer recording sheet - Google Patents

Abstract

PURPOSE: To provide a sublimation transfer recording color sheet capable of obtaining an image having high sensitivity and excellent gradability without fusion bonding to an image receiver at the time of recording with high energy in a sublimation transfer recording system. CONSTITUTION: A layer containing ionomer resin is provided on the coloring material layer of a sublimation transfer recording color sheet to obtain an image having high sensitivity and excellent gradability without fusion bonding to an image receiver even at the time of recording with high energy.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sublimation type transfer recording sheet which is easy to peel off and is excellent in continuous gradation expression.

[0002]

Various methods such as electrophotography, ink jet, and heat-sensitive transfer recording have been studied for color recording, but the heat-sensitive transfer method requires that the apparatus be maintainable, easy to operate, and have high image quality. In this respect, it is more advantageous than other methods. In particular, in the sublimation transfer recording method, the image receiver is superposed on the ink application surface of the sublimation transfer recording sheet coated with ink containing a sublimable or heat diffusible dye, and the back surface of the sublimation transfer recording sheet is heated by a thermal head. Then, only the dye in the sublimation transfer recording sheet is transferred to the image receptor,
Like silver halide photography, it has the feature that continuous gradation can be expressed.

However, since the temperature of the thermal head during transfer recording generally exceeds 300 ° C., when a conventional recording sheet is used, the binder resin in the color material layer of the recording sheet is softened or melted by heat. , The recording sheet and the image receptor are fused, and peeling after recording becomes difficult,
There is a problem that the binder resin is transferred to the image receptor together with the dye, which makes gradation expression impossible.

Further, during transfer recording, since the recording sheet and the image receiving body are superposed and conveyed, friction between contact surfaces of the two causes a phenomenon of thread smearing in which a non-printed portion of the image receiving body is contaminated. There was a problem. As a method for preventing the fusion of the recording sheet and the image receptor, a method of improving heat resistance by using a crosslinkable resin for the binder resin of the recording sheet and the resin of the image receptor (Japanese Patent Laid-Open No. 58-2153).
97, JP-A-58-212994 and JP-A-58-215398) or a method for improving releasability by incorporating a release agent into the binder resin of the recording sheet and the resin of the image receptor. (JP-A-62-29
4596, JP-A-63-134239, etc.) have been proposed.

A method of providing a dye-permeable heat-resistant protective layer on the color material layer of the recording sheet (Japanese Patent Laid-Open No. 60-2245).
Japanese Patent Laid-Open No. 90 and Japanese Patent Laid-Open No. 61-1148095) have been proposed. However, recently, in the recording method of this system, high-speed recording is increasingly demanded, and a recording material that can withstand more severe recording conditions is required.
Compared with the conventional time, within 1/2 to 1/3 or less, that is, 10
Since the maximum recording temperature of the recording material rises because the recording is performed at about mm seconds / period or less, the above method is insufficient and becomes a problem.

Further, the method of providing a protective layer of a so-called heat-resistant resin on the color material layer inevitably impedes the permeation of the dye, so that a decrease in sensitivity cannot be avoided and is not sufficient.

[0007]

DISCLOSURE OF THE INVENTION In the present invention, a coloring material layer containing a sublimable or heat diffusible dye is provided on a substrate, and a coloring material layer is provided thereon.
Further, by providing a specific peelable protective layer, the peelability from the image receptor after transfer recording is good, scratches are not generated on the non-printed portion of the image receptor, and high sensitivity and good storage stability are obtained. It is an object to provide a sublimation transfer recording sheet which gives an image and a method thereof.

[0008]

The inventors of the present invention have arrived at the present invention as a result of earnest research for the purpose of solving the above problems. That is, the above-mentioned object of the present invention is a sublimation type thermal transfer recording sheet having a heat transferable color material layer on one surface of a base film and a heat resistant slipping layer on the other surface of the base film. The solution is to provide a layer containing an ionomer resin on top.

Hereinafter, the present invention will be described in detail. Sublimation transfer recording sheet of the present invention (hereinafter referred to as recording sheet)
Is a heat-resistant slip layer provided on one side of the base film, and a sublimation type transfer recording ink, which becomes a coloring material layer, is applied to the other side of the base film, and after drying, a releasable protective layer mainly composed of an ionomer resin. Can be obtained by providing.

The base film is not particularly limited, and examples thereof include polyethylene terephthalate film, polyamide film, polyaramid film, polyimide film, polycarbonate film, polyphenylene sulfide film polysulfone film, cellophane, triacetate film and polypropylene film. To be Among them, polyethylene terephthalate film has mechanical strength, dimensional stability, heat resistance,
A biaxially stretched polyethylene terephthalate film is preferable in terms of price and the like. The thickness of these base films is 1 to 30 μm, preferably 2 to 10 μm
It is. The heat resistant slipping layer usually contains additives such as a binder resin, fine particles and a lubricant. As the binder resin, a thermosetting, photocurable or thermoplastic binder resin is used.

Examples of the thermosetting resin include crosslinked products of a resin containing active hydrogen such as ethyl cellulose resin, cellulose acetate resin, polyvinyl alcohol resin, polyvinyl acetal resin, polyvinyl butyral resin and isocyanate. Examples of the photocurable resin include polyester acrylate resin, epoxy acrylate resin, and polyol acrylate resin.

The thermoplastic resin has a glass transition temperature of 5
A normal thermoplastic resin having a temperature of 0 ° C. or higher can be used,
For example, acrylic resin, vinyl chloride copolymer, acrylonitrile-styrene copolymer, polycarbonate resin,
Examples thereof include polyester resins, polyvinyl butyral resins and polyacetal resins. Examples of the fine particles include inorganic particles such as silica, alumina and titanium oxide, and organic fine particles such as silicone resin, urea resin and benzoguanamine resin.

As the lubricant, various modified silicone oils, phosphate ester type surfactants, fatty acid metal salt type surfactants and the like are used. As a coating method used for forming the heat resistant slipping layer, for example, a method using a gravure coater, a reverse coater, or an air doctor coater described in “Coating Method” by Yuji Harasaki (1979, published by Maki Shoten). And various other methods.

In addition to the above components in the ink, if necessary, organic or inorganic non-sublimable particles, a dispersant, an antistatic agent, an antiblocking agent, an antifoaming agent, an antioxidant, a viscosity modifier, and the like. Additives can be added. The ink may be applied by the same method as the case of the heat resistant slipping layer,
The thickness of the heat-resistant lubricating layer formed on the base film is
It is usually 0.1 to 10 μm, preferably 0.3 to 5 μm.

The sublimation transfer recording ink is obtained by mixing and dissolving a sublimation or heat diffusible dye and a binder resin having good heat resistance in a suitable solvent to prepare a solution. Examples of the sublimable or heat diffusible dyes include azo type, anthraquinone type, nitro type,
Various nonionic dyes such as styryl-based, naphthoquinone-based, quinophthalone-based, azomethine-based, coumarin-based, and condensed polycyclic dyes are used.

As the binder resin, polycarbonate resin, polysulfone resin, polyvinyl butyral resin, phenoxy resin, polyarylate resin, acrylate resin, polyamide resin, polyimide resin, polyaramid resin, polyetherimide resin, polyester resin,
Examples include acrylonitrile-styrene resins and cellulosic resins such as acetyl cellulose, methyl cellulose, ethyl cellulose and the like.

Examples of the solvent include aromatic solvents such as toluene and xylene; ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; ester solvents such as ethyl acetate and butyl acetate; alcohol solvents such as isopropanol, butanol and methyl cellosolve. Solvents, ether solvents such as dioxane and tetrahydrofuran, amide solvents such as dimethylformamide and N-methylpyrrolidone, etc. are used.

The thickness of the color material layer formed on the base film is usually 0.1 to 10 μm, preferably 0.3 to 5 μm as a dry film thickness. In the present invention, a peelable protective layer mainly containing an ionomer resin is further provided on the color material layer. During transfer recording, it is important that the heat of the thermal head does not melt and stick to the image receptor, and it is also important that the dye that migrates from the color material layer can be transmitted.
As a peelable protective layer, it is difficult to be compatible with the dye layer resin of the image receptor,
An ionomer resin having high dye permeability is used.

Specifically, an ionomer resin having a property of being highly compatible with the dyeing layer resin of the image receptor and having high dye permeability is used as the peelable protective layer. An ionomer resin generally has a structural characteristic in which ionic bonding crosslinks are partially introduced between polymer chains, and unlike general heat resistant resins, it has a crosslinked structure in a normal temperature range. Therefore, it is difficult to be compatible with other resins, but it has characteristics that it has fluidity due to dissociation of ionic bond in a higher temperature region and is soluble in a solvent.

Examples of the ionomer resin include ethylene-methacrylic acid copolymers, ethylene-acrylic acid copolymers, butadiene-acrylic acid copolymers, styrene-methacrylic acid copolymers, and carboxylic acid groups on the side chains. , A hydrogenated polypentamer having an ionic bond group such as a sulfo group introduced therein, a polystyrene ionomer or a fluorine ionomer, or a urethane ionomer having an ionic bond group such as a carboxylic acid group or a sulfo group introduced into its side chain Examples include elastomeric ionomers such as polyester-based ionomers, ethylene-propylene-diene copolymer ionomers, and acrylonitrile-butadiene copolymers. Further, these may be used after neutralizing the acid group portion with an alkali metal ion such as lithium ion or sodium ion, an alkaline earth metal ion such as magnesium ion, calcium ion or the like.

Generally, the above ionomer resin is supplied as an aqueous solution or dispersion at a concentration of about 30% by weight, so that the ionomer resin may be directly altered on the color material layer as it is or by diluting it slightly with water or the like. Without applying and drying, the peelable protective layer can be easily formed on the color material layer. The coating method of these inks can be carried out by the same method as described for the coating of the heat resistant slipping layer,
The coating film thickness is usually 0.01 to 1 μm, preferably 0.05 to 0.2 μm as a dry film thickness.

In the production of the thermal transfer recording sheet of the present invention, the surface of the base film is subjected to corona treatment in order to improve the adhesiveness between each layer formed by the above coating and the base film, or An undercoating treatment with a polyester resin, a cellulose resin, a polyvinyl alcohol resin, a urethane resin, a polyvinylidene chloride resin, or the like may be performed.

Further, with respect to the above ionomer resin,
The adhesiveness may be improved by blending an aqueous solution or dispersion of polyester resin, cellulose resin, polyvinyl alcohol resin, urethane resin, polyvinylidene chloride resin, etc. up to about 5 times.

[0024]

EXAMPLES The present invention will be described below in more detail with reference to examples, but the examples do not limit the present invention in any way. Example 1 (a) Preparation of thermal transfer recording sheet A biaxially stretched polyethylene terephthalate film (thickness: 5 μm) was used as a base film, and a coating solution having the following composition was applied to one surface of the film at a wet film thickness of about 10 μm. Apply
It was dried at 100 ° C. for 1 minute to form a heat resistant slipping layer.

[0025]

[Table 1] Acrylic resin (Mitsubishi Rayon Co., Ltd., Dianal BR-108) 8.25 parts Amino-modified silicone (Shin-Etsu Chemical Co., Ltd., KF-857) 0.6 parts Carboxy-modified silicone (Shin-Etsu Chemical Co., Ltd., X-) 22-162C) 0.6 part Aerosil silica (R-812 manufactured by Nippon Aerosil Co., Ltd.) 0.25 part Spherical silicone resin (Trefil R-930 manufactured by Toray Silicone Co., Ltd.) 0.25 part Toluene / methyl ethyl ketone (mixing ratio: 2 / 1) 90 copies

On the film provided with the above heat resistant slipping layer,
Cyan type thermal diffusible dye 5 represented by the following structural formula (1)
Department, AS resin (made by Denki Kagaku Kogyo Co., Ltd., trade name DENKA A
S-S) 10 parts, toluene 85 parts, cyclohexanone 1
Apply 0 parts of ink and dry to dry film thickness of about 1μ
m color material layer was formed.

A polyurethane ionomer aqueous dispersion (manufactured by Dainippon Ink and Chemicals, Inc., trade name Hydran H) is further provided as a peelable protective layer on the color material layer.
A color sheet of the present invention was prepared by applying a 10% solid solution of W-100) and drying it to form a peelable protective layer having a dry film thickness of about 0.2 μm.

[0028]

Embedded image

(B) Preparation of image receptor A coating solution having the following composition was applied to a polypropylene synthetic paper having a thickness of 150 μm with a wire bar and dried to a dry thickness of about 5 μm.
An image receptor having a dyeing layer of m was obtained.

[0030]

[Table 2] Polyvinylphenyl acetal resin 100 parts Silicone varnish for modification 30 parts (TSR-160 manufactured by Toshiba Silicone Co., Ltd.) Toluene 500 parts Methyl ethyl ketone 500 parts

The polyvinyl phenyl acetal resin is obtained by acetalizing polyvinyl alcohol (saponification degree 99 mol%, polymerization degree 1700) with phenyl acetaldehyde.

(C) Transfer recording test The coated surface of the cyan color material layer and the releasable protective layer of the above color sheet is overlapped with the surface of the dyeing layer of the image receptor prepared in the above (b), and a heating resistor of 8 dots / mm is formed. Transfer was performed under the following conditions using a thin film type line thermal head having a density.

[0033]

[Table 3] Recording line density 8 lines / mm Thermal head applied power 0.4 W / dot Thermal head applied pulse width 2, 4, 6, 8, 1
0 ms / dot

As a result, the color sheet and the image receptor could be easily separated after the recording without fusion of the color sheet and the image receptor during recording. In addition, no scratch stain was observed in the non-printed portion of the image receptor, and the color density of the transferred image was 0.12, 0.28, 0.
Images having high sensitivity of 52, 0.80, and 1.10 and good gradation were obtained.

Example 2 Instead of using the polyurethane ionomer aqueous dispersion as the peelable protective layer in (a) of Example 1, an aromatic polyester ionomer aqueous dispersion (Dainippon Ink and Chemicals, Inc.) is used. Product name, Finetex, ES-67
A color sheet was prepared in the same manner as in Example 1 except that the 10% solid content solution of 0) was applied and dried to form a peelable protective layer having a dry film thickness of 0.2 μm. Using this color sheet, a transfer recording test was conducted under the same conditions as in (c) of Example 1 using the same image receptor as in (b) of Example 1.

As a result, the color sheet and the image receptor could be easily peeled off after the recording without fusing between the color sheet and the image receptor. In addition, no scratch stain is observed in the non-printed portion of the image receptor, and the color density of the transferred image is 0.12, 0.27, 0.
Images with high sensitivity of 50, 0.76 and 1.05 and good gradation were obtained.

[Comparative Example 1] The same as Example 1 except that the color sheet was prepared without coating the polyurethane ionomer aqueous dispersion as the peeling protective layer in (a) of Example 1. The transfer recording test with the image receptor was conducted by the method. As a result, the color sheet and the image receptor are fused during recording, and it is difficult to separate the color sheet and the image receptor after recording, and the entire color material layer of the color sheet is fused on the surface of the peeled image receptor. However, an image with gradation was not obtained at all.

[Comparative Example 2] In (a) of Example 1, a 5% aqueous solution of hydroxyethyl cellulose resin was applied and dried instead of the polyurethane ionomer aqueous dispersion as the peelable protective layer, and the dry film thickness was increased. A color sheet was prepared in the same manner as in Example 1 except that a heat resistant protective layer having a thickness of about 0.2 μm was formed. Using this color sheet, a transfer recording test was conducted under the same conditions as in (c) of Example 1 using the same image receptor as in (b) of Example 1.

As a result, the releasability at the time of recording was good, but the color density of the transferred image was 0.12, 0.23, depending on each application time described in (C) of Example 1. 0.4
The values were 2, 0.65 and 0.94, and the sensitivity was lower than that of Example-1, and an image having a sufficient density could not be obtained.

[0040]

The sublimation type thermal transfer recording sheet of the present invention comprises:
Even at the time of high-energy recording, the recording sheet and the image receptor are not fused to each other, and an image with high sensitivity and good gradation can be obtained, which is extremely useful in industry.

Claims (1)

[Claims] 1. A sublimation type thermal transfer recording sheet having a heat transferable color material layer on one surface of a base film and a heat resistant slipping layer on the other surface, wherein an ionomer resin is provided on the color material layer. A sublimation type transfer recording sheet characterized by comprising a layer containing the same.