JP2583852B2 - Transfer type thermal recording medium - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-sensitive recording material used for heat-sensitive recording, and more particularly to a transfer-type heat-sensitive recording material whose viscosity is reduced in response to a heat signal to obtain a good halftone. .

2. Description of the Related Art Conventionally, as a transfer type thermal recording medium in this field, as described in Japanese Patent Application No. 59-246649, for example, an ink material containing an alicyclic saturated hydrocarbon resin and a colorant, A thermal transfer layer has been proposed in which ink transfer assisting particles having a particle size greater than the thickness of a layer made of a material are mixed in the ink material.

Problems to be Solved by the Invention In the conventional transfer-type thermal recording medium that provides high image quality, when the recording medium is rubbed with, for example, a finger or the like, it is easily rubbed off and the fixability is insufficient. Further, the image quality of a conventional transfer type recording medium giving high fixing properties was insufficient.

An object of the present invention is to provide a transfer type thermal recording medium having high image quality and high fixability.

Means for solving the problem A thermosensitive recording medium in which a coloring material layer containing a coloring material and a resin is applied on a substrate, wherein the resin is bonded to a resin A having a strong adhesive strength with the substrate. This is a transfer type thermosensitive recording medium containing resin B having low strength as a main component.

Function Resin A having a strong adhesive strength to the base material in the color material layer contributes to high fixability, and resin B having a weak adhesive strength to the base material contributes to peelability of the color material layer from the base material.

The term “adhesive strength” as used herein refers to the strength of adhesion between a substrate and a resin. That is, the strength of the adhesive force between the base material and the resin constituting the color material layer.

Embodiment FIG. 1 is a cross-sectional view schematically illustrating an embodiment of the thermal transfer recording medium of the present invention. In this embodiment, a color material layer 4 including a resin 2 and a color material 3 is provided on one surface of a substrate 1.

As the base material 1, a polymer film such as polyvinyl chloride, polyester, polyamide or the like is provided.

The resin 2 includes a resin A having a strong adhesive strength to the substrate 1 and a resin B having a weak adhesive strength to the substrate 1.

When the substrate 1 is a polyvinyl chloride film, the resin A is preferably at least one of soft vinyl chloride resin, ethylene-vinyl acetate copolymer resin, and vinyl chloride-vinyl acetate copolymer resin. When the substrate 1 is a polyester film, the resin A is preferably at least one of saturated polyester, ethylene / vinyl acetate copolymer resin, and silicone resin. When the substrate 1 is a polyamide film,
The resin A is preferably at least one of phenol resin, urea / melamine resin, urethane resin and vinyl acetate resin.

When the substrate 1 is a polyvinyl chloride film, the resin B is preferably at least one of vinyl acetate resin and acrylonitrile-styrene copolymer resin. When the base material 1 is a polyester film, the resin B is vinyl chloride / vinyl acetate copolymer resin, vinyl acetate resin, acrylonitrile /
At least one of phenol copolymer resin and acrylonitrile-styrene copolymer resin is preferred. When the substrate 1 is a polyamide film, the resin B is at least one of vinyl chloride resin, vinyl chloride copolymer resin, and ethylene / vinyl acetate copolymer resin.

The mixing ratio A / B of the resin A and the resin B differs depending on the type of the substrate 1, but is preferably in the range of 0.01 to 100. Below this range, the adhesive strength between the base material 1 and the color material layer 4 is too weak, so that the fixability of the transfer type thermosensitive recording medium is significantly deteriorated. Since the adhesive strength is too strong, the releasability of the color material layer of the transfer type thermal recording medium is significantly deteriorated.

Coloring material 3 is a dye such as an acid dye, a basic dye, a disperse dye,
Organic or inorganic pigments are provided.

FIG. 2 is a sectional view schematically illustrating another embodiment of the present invention. In this embodiment, a color material layer 6 including a resin 2, a color material 3 and an additive material 5 is provided on one surface of a substrate 1.

The additive material 5 is a material that lowers the viscosity of the color material layer 6, and the additive material 5 is at least one of a plasticizer, an oligomer, and paraffin.

Any plasticizer may be used as long as it has a plasticizing effect on the resin 2, but a plasticizer having high compatibility with the resin 2 and lowering the thermo-viscous properties of the resin 2 is preferable.

Examples of the oligomer include a xylene resin, a phenol resin, a polyester polyol, a maleic resin, an amide resin, a fatty acid amide, a coumarone / indene resin, a low molecular weight polyethylene, a low molecular weight polypropylene, and the like.

Paraffin having a melting point of 40 to 100 ° C is provided. The coloring material layer 4 or 6 may contain particles. These particles have an effect of making the color material layer 4 or 6 easily cut. When the particles have a particle size larger than the thickness of the layer formed by the color material layer 4 or 6, in addition to the above-described effects, the particles act as transfer auxiliary particles for mainly transferring the particles.

Examples of the material of the particles include aluminum oxide, calcium carbonate, silicon dioxide, polycarbonate, nylon, guanamine resin, and polypropylene.

The thickness of the color material layer 4 or 6 is preferably 1 to 15 μm. When the thickness is 1 μm or less, the thickness of the color material layer is too thin, so that the maximum density at the time of transfer recording becomes low. On the other hand, when the thickness is 15 μm or more, the heat capacity of the color material layer becomes too large, and it is necessary to apply high energy to the heat source. Therefore, the average particle size is
It is preferably 15 μm or less.

 Hereinafter, specific examples will be described.

Example-1 A coating liquid was prepared with a composition as described below.

Resin A: Ethylene / vinyl acetate copolymer resin [Ultracene 760 (manufactured by Toyo Soda Kogyo Co., Ltd.)] 70 parts by weight Resin B: Acrylonitrile / styrene copolymer resin [Denka AS-S (Denki Chemical Industry Co., Ltd. 1) parts by weight Coloring material: carbon black 30 parts by weight Solvent: ethyl acetate 300 parts by weight The above composition was dispersed in a ball mill for 20 hours to obtain a coating liquid.

This coating solution was applied on a polyvinyl chloride film [Vinifoil (manufactured by Mitsubishi Plastics, Inc.)] with a bar coater, and the solvent was dried to a thickness of 2 μm to obtain a recording medium 1.

Example-2 A coating liquid was prepared with a composition as described below.

Resin A: phenolic resin [Super Beckasite 1001 (Dainippon Ink Chemical Industry Co., Ltd.)] 5 parts by weight Resin B: Vinyl chloride / vinyl acetate copolymer resin [Denka Vinyl # 1000A (Denki Kagaku Kogyo Co., Ltd. or below) 75% by weight Coloring material: 30 parts by weight of phthalocyanine-based cyan pigment Additive: Paraffin [HNP10 (Nippon Seiro Co., Ltd.)] 7
Parts by weight Solvent: 400 parts by weight of toluene The above composition was dispersed in a ball mill for 20 hours to obtain a coating liquid.

This coating liquid was applied on a polyamide film [Emblem ON (manufactured by Unitika)] with a bar coater, and the solvent was dried to a thickness of 13 μm to obtain a recording medium 2.

Example-3 Two kinds of coating liquids were prepared with the composition as described below.

Yellow paint Resin A: Saturated polyester [Vylon # 200 (same as below manufactured by Toyobo Co., Ltd.)] 30 parts by weight Resin B: Vinyl chloride / vinyl acetate copolymer resin [Denka vinyl # 1000A] 30 parts by weight Additive: xylene Resin [Nicanol L (manufactured by Mitsubishi Gas Chemical Co., Ltd.)] 10 parts by weight Coloring material: disazo yellow pigment 40 parts by weight Solvent: ethyl acetate 300 parts by weight The above composition was dispersed in a ball mill for 20 hours to obtain a yellow coating liquid. .

Cyan paint A cyan paint was used in the same manner as the yellow paint except that the coloring material was changed to a phthalocyanine-based cyan pigment among the yellow paints described above.

These coating liquids are coated on a polyester film [Lumirror (hereinafter referred to as Toray Industries, Inc.)] with a bar coater, and the solvent is dried to a thickness of 3 μm to obtain a recording material 3Y (yellow paint) and a recording material 3C (cyan paint). ).

Example-4 A coating liquid was prepared with a composition as described below.

Resin A: Silicone resin [KR211 (Shin-Etsu Silicone Co., Ltd.)
10 parts by weight Resin B: Vinyl chloride / vinyl acetate copolymer resin [Denka Vinyl # 1000D (manufactured by Denki Kagaku Kogyo Co., Ltd.)] 50 parts by weight Additive: polyester polyol [Polylite OD-X-
2108 (manufactured by Dainippon Ink and Chemicals, Inc.)] 6 parts by weight Color material: quinacridone-based magenta pigment 45 parts by weight Particles: silicon dioxide [Aerosil R972 (manufactured by Nippon Aerosil Co., Ltd.)] 15 parts by weight Solvent: toluene 300 parts by weight Parts The above composition was dispersed in a ball mill for 20 hours to obtain a coating liquid.

Apply this coating solution on a polyester film (Lumirror)
Coating was performed with a bar coater, and the solvent was dried to obtain a recording medium 4 having a thickness of 5 μm.

Example-5 A coating liquid was prepared with a composition as described below.

Resin A: 40 parts by weight of saturated polyester [Vylon # 200] Resin B: 20 parts by weight of vinyl chloride / vinyl acetate copolymer resin [Denka vinyl # 1000A] Additive: Polyester plasticizer [Polysizer W1000 (Dainippon Ink & Chemicals, Inc. 5 parts by weight Color material: CI Disperse Yellow 8 20 parts by weight Particles: Aluminum oxide (fused white alumina)
WA # 4000 (manufactured by Fujimi Abrasives Co., Ltd.)] 80 parts by weight Solvent: ethyl acetate 300 parts by weight Of the above composition, after dissolving the particles other than the particles, add the particles, and disperse them for 2 hours with a ball mill. To give a coating solution.

Apply this coating solution on a polyester film (Lumirror)
Coating was performed with a bar coater, and the solvent was dried to obtain a recording medium 5 having a thickness of 3 μm.

Comparative Example-1 Two types of coating liquids were prepared with compositions as described below.

Yellow paint Resin A: Saturated polyester [Vylon # 200] 60 parts by weight Coloring material: Disazoyero pigment 40 parts by weight Solvent: ethyl acetate 300 parts by weight The above composition was dispersed in a ball mill for 20 hours to obtain a yellow coating liquid.

Cyan paint A cyan paint was used in the same manner as the yellow paint, except that the coloring material was changed to a phthalocyanine cyan pigment among the yellow paints described above.

Polyester film (Lumirror)]
The top is coated with a bar coater, the solvent is dried and the thickness is 3 μm
Thus, a recording body 1′Y (yellow paint) and a recording body 1′C (cyan paint) were obtained.

Comparative Example-2 Two kinds of coating liquids were prepared with the composition as described below.

Yellow paint Resin B: Vinyl chloride / vinyl acetate copolymer resin [Denka vinyl # 1000A] 60 parts by weight Coloring material: Disazoiello pigment 40 parts by weight Solvent: ethyl acetate 300 parts by weight The above composition is dispersed in a ball mill for 20 hours. It was a yellow coating liquid.

Cyan paint A cyan paint was used in the same manner as the yellow paint, except that the coloring material was changed to a phthalocyanine cyan pigment among the yellow paints described above.

These coating liquids were applied on a polyester film [Lumirror] using a bar coater, and the solvent was dried to a thickness of 3 μm to obtain a recording material 2′Y (yellow paint) and a recording material 2′C (cyan paint).

The above-mentioned recording bodies 1 to 5 and recording bodies 1 'and 2' were recorded on polypropylene synthetic paper as an image receiving body based on the following recording specifications.

Recording specifications Thermal head 4 dots / mm thin film flat line head Recording cycle 16.7 ms / line Applied power 10 mW / mm ² Applied pulse width 0 to 4 ms The results of recording are shown in Table 1.

The fixability was evaluated by a method according to JIS-L-0849, and Table 1 shows [recording body fixability] represented by the following formula.

The transcripts 3Y, 3C and the transcripts 1'Y, 1'C and 2'Y,
For 2'C, color overlay recording was also performed. 1
The color was recorded with the yellow color material layer and then with the cyan color material layer. Among these characteristics, the characteristics (trapping characteristics) when a cyan gradation pattern is printed on the maximum density of yellow are shown in FIGS. The method for measuring the trapping characteristics is as described below.

Trapping characteristic measurement method Trapping characteristics of cyan The maximum density of yellow (Dmax) is measured through a red filter (yellow cyan component). (D1) Measure the density on the pattern for which trapping is to be measured through a red filter (cyan color density). (D2).

Subtract D1 from D2 and add the paper density (D4) passed through the red filter. (D3) [D3] = [D2]-[D1] + [D4] The density of the cyan monochrome tone pattern is measured through a red filter (cyan color density). (D0) This is called the trapping characteristic of cyan of D3, and is compared with D0. (It is better that D3 coincides with D0) As is clear from Table 1, the transfer body of the present invention has a high fixing property and an excellent image quality.

Further, as is apparent from FIGS. 4, 6, and 7, the transfer body of the present invention has excellent trapping characteristics.

Effect of the Invention The transfer type thermal recording medium of the present invention contains, as main components, a resin A having a strong adhesive strength with the base material and a resin B having a weak adhesive strength with the base material, and thus has high image quality and high fixing. It is a recording body of sex.

Further, when the transfer type thermosensitive recording medium of the present invention is applied to a color image, the trapping characteristics are good.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically illustrating one embodiment of the transfer type thermal recording medium of the present invention, FIG. 2 is a cross-sectional view schematically illustrating another embodiment, FIG. 3, FIG. FIG. 5 is a diagram showing recording density characteristics in the example, and FIGS. 6 and 7 are diagrams showing recording density characteristics in the comparative example. 1 ... substrate, 2 ... resin, 3 ... coloring material, 4 ... coloring material layer,
5 ... additive material, 6 ... color material layer.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Nobuyoshi Taguchi 1006 Kazuma Kadoma, Matsushita Electric Industrial Co., Ltd. (56) References JP-A-60-234889 (JP, A)

Claims (7)

(57) [Claims] 1. A thermosensitive recording medium in which a color material layer containing a color material and a resin is applied on a substrate, wherein the resin is a resin A having a high adhesive strength to the substrate and a resin B having a low adhesive strength. And a transfer-type thermosensitive recording material characterized by containing: 2. The method according to claim 1, wherein the base material is a polyvinyl chloride film and the resin A
Is at least one member selected from the group consisting of a soft vinyl chloride resin, an ethylene-vinyl acetate copolymer resin, and a vinyl chloride-vinyl acetate copolymer resin, and the resin B is a vinyl acetate resin, an acrylonitrile-styrene copolymer resin. 2. The transfer-type thermosensitive recording medium according to claim 1, which is at least one type selected from the group. 3. A base material is a polyester film, the resin A is at least one selected from the group consisting of a saturated polyester, an ethylene / vinyl acetate copolymer resin and a silicone resin, and the resin B is a vinyl chloride / vinyl acetate copolymer. 2. The transfer type thermosensitive recording material according to claim 1, wherein the thermosensitive recording material is at least one selected from the group consisting of a coalescing resin, a vinyl acetate resin, an acrylonitrile-phenol copolymer resin, and an acrylonitrile-styrene copolymer resin. 4. The base material is a polyamide film, the resin A is at least one selected from the group consisting of a phenol resin, a urea / melamine resin, a urethane resin, and a vinyl acetate resin, and the resin B is a vinyl chloride resin, a vinyl chloride resin. 2. The transfer type thermosensitive recording medium according to claim 1, wherein the thermosensitive recording medium is at least one selected from the group consisting of a vinyl acetate copolymer resin and an ethylene / vinyl acetate copolymer resin. 5. The transfer type thermosensitive recording material according to claim 1, wherein the ratio A / B of the resin A to the resin B is in the range of 0.01 to 100. 6. The transfer type thermosensitive recording material according to claim 1, wherein the coloring material layer contains at least one additive selected from the group consisting of a plasticizer, an oligomer and paraffin. 7. The method according to claim 1, wherein the color material layer contains particles.
Item 7. The transfer type thermosensitive recording material according to item 6 or 6.