JPH06127155A - Image receiving medium for sublimation type thermal transfer and recording method using same - Google Patents

Abstract

PURPOSE:To obtain a high density image excellent in uniformity, in an image receiving medium used in combination with a recording medium for sublimation type thermal transfer, by forming a support having a dye receiving layer provided on the upper surface thereof from an air bubble-containing plastic film having specific density. CONSTITUTION:An image receiving medium for sublimation type thermal transfer is used in combination with a recording medium for sublimation type thermal transfer having a transfer layer containing a heat-sublimable dye. In this case, the image receiving medium is constituted of at least a support 1 and the dye receiving layer 2 provided on the upper surface thereof. The support 1 is formed from an air bubble containing plastic film having density satisfying formula (Do-D)/Do>0.3 (wherein Do is the density of a plastic film composed of the same material and containing no air bubbles). In thermal transfer recording, the transfer layer of the recording medium and the dye receiving layer 2 of the image receiving medium are opposed each other and heated on the side of the recording medium under the condition of speed of image receiving medium/speed of recording medium >1 to perform printing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image receiving medium for sublimation type thermal transfer which is used in combination with a thermal transfer recording medium having a transfer layer containing a thermal sublimation type dye, and an n-times mode multiple recording method using the same. .

[0002]

2. Description of the Related Art A sublimation type thermal transfer recording system using a thermal transfer recording medium having a transfer layer containing a thermal sublimable dye and an image receiving medium for receiving a dye sublimated by thermal printing from the back surface of the recording medium is excellent. In recent years, it has attracted attention as a medium capable of halftone recording and providing a full-color hard copy similar to a color photograph.

However, in this recording method, in order to obtain one full-color image, one recording medium (ink sheet) for each of yellow, magenta, cyan, and (black) is used, and then an unused portion exists. However, it has the disadvantage of high running cost because it is discarded. Therefore, in order to improve this drawback, in recent years, a method of printing and recording many times by repeatedly using the same ink sheet has been performed. Specifically, the ink sheet and the image receiving medium (image receiving sheet)
And a constant velocity mode method in which printing is repeatedly performed while traveling at a constant velocity, and the speed of the image receiving sheet is set to n of the speed of the ink sheet.
There are two methods, an n-fold mode method, in which double printing (n> 1) is performed repeatedly while both sheets are running.

The latter n-fold mode method prints a large number of times by a relative speed method in which the portion used before the ink layer and the portion used after the ink layer are slightly shifted from each other while being shifted. The multi-time recording method based on the n-fold mode method described above is a mere repeated use of the used portion because the unused portion of the ink layer is always supplied every time printing is performed. Compared with the recording method, there is an advantage that the variation in the remaining ink amount due to the recording history can be reduced.

Further, in this recording system, a sublimable dye is used as an image-receiving sheet on paper such as synthetic paper, high-quality paper, art paper, etc., and on a substrate made of plastic such as polyester (especially polyethylene terephthalate) or polypropylene. What is formed by coating a dye-receptive layer containing a thermoplastic polyester resin or a vinyl chloride / vinyl acetate copolymer resin as a main component, which exhibits strong dyeing property with respect to the above is used. In particular, when a polyethylene terephthalate (hereinafter sometimes abbreviated as PET) film is used as the substrate, the smoothness of the image surface is maintained even when recording is performed by applying high energy, and the glossiness is high even in a high density image area. Has the advantage of not decreasing. However, when a PET film is used, there is a drawback that the adhesion between the ink sheet and the image receiving sheet is insufficient and it is difficult to obtain a clear image.

Therefore, in order to solve this drawback, an image-receiving sheet made of a polyester film containing fine bubbles satisfying specific conditions has been proposed (Japanese Patent Publication No.
16078). The inventors of the present invention also used an image-receiving sheet in which a dye-receiving layer is provided on a substrate having a PET film containing microbubbles on at least the surface (JP-A-3-266691), and an n-fold mode method using the image-receiving sheet. A recording method (Japanese Patent Laid-Open No. 4-45954) has been proposed.

[0007]

However, even with such an image receiving sheet, in the n-fold mode method, since the ink sheet and the image receiving sheet rub against each other, the granular dye in the transfer layer of the ink sheet is Since the image is likely to be transferred to an image-receiving sheet and grainy, it is difficult to obtain a uniform image, and a curable resin is preferably used in the dye-receiving layer from the viewpoint of dyeing property and releasability, so that the sensitivity is high. The drawback remains that it tends to decline.

Therefore, it is an object of the present invention to obtain a uniform image without roughness even in the low density image portion even when the n-fold mode method is adopted, and also to increase the sensitivity and to obtain a high image density even in the low energy application portion. Another object of the present invention is to provide an image receiving medium for sublimation type thermal transfer capable of obtaining

[0009]

According to the present invention, there is provided an image receiving medium which is used in combination with a sublimation type thermal transfer recording medium having a transfer layer containing a thermal sublimation dye, at least a substrate and at least the substrate. A density D which is composed of a dye receiving layer provided on the upper surface and the substrate satisfies the following formula
An image receiving medium for sublimation type thermal transfer is provided, which comprises a bubble-containing plastic film having

[Equation 1] (In the above formula, D ₀ represents the density of a plastic film containing the same material as that of the above-mentioned substrate and containing no bubbles.)

That is, the image receiving medium for sublimation type thermal transfer of the present invention is characterized in that a bubble-containing plastic film having a density D satisfying the above formula 1 is used as a substrate thereof. As a result of these studies, among the conventionally proposed bubble-containing plastic films,
The present inventors have found that the use of a bubble-containing plastic film having the above-mentioned density D is particularly preferable, and arrived at the present invention. According to the image receiving medium of the present invention, it is possible to obtain a uniform image without roughness even in a low-density image portion, and high sensitivity,
High image density can be obtained even in the low energy application section. Especially when the image receiving medium is applied to the n-fold mode method, the effect is remarkable.

The image receiving medium for sublimation thermal transfer of the present invention will be described in detail below. The image receiving medium of the present invention is basically composed of two layers, a substrate and a dye receiving layer, as shown in FIG. 1, and the substrate contains bubbles having a density D satisfying the above formula (1). Made of plastic film. In FIG. 1, 1 is a bubble-containing plastic film (substrate) and 2 is a dye receiving layer.

The bubble-containing plastic film having the density D used in the present invention is polyester,
Known films such as vinyl chloride, polycarbonate, polypropylene, polyethylene and acetate can be used. Of these, polyester and polypropylene are preferable.

Further, in the present invention, a laminated body of two or more layers obtained by laminating the bubble-containing plastic film having the density D and at least one plastic film or paper which is the same as or different from the film. Can also be used. That is, a laminated body of a bubble-containing plastic film and paper (fine paper, coated paper, art paper, gravure paper, baryta paper, synthetic paper, etc.), a plastic film, a bubble-containing plastic film and the like can be used. As the laminating agent, known adhesives, pressure-sensitive adhesives and release agents are used.

As a concrete example of the structure using the bonded body, for example, a bubble-containing plastic film /
Examples include paper (FIG. 2), bubble-containing plastic film / plastic film (FIG. 3), bubble-containing plastic film / paper / bubble-containing plastic film (FIG. 4), and the like. In the figure, 1 is a bubble-containing plastic film,
2 is a dye receiving layer, 3 is paper, and 4 is a plastic film. In addition, among these bonded bodies,
Particularly preferred specific examples include bubble-containing polyester /
Paper, bubble-containing polyester / white polyester, bubble-containing polypropylene / paper, bubble-containing polypropylene / white polyester, and the like. When such a bonded body is used, it is possible to prevent deterioration of the heat resistance of the film due to the presence of air bubbles by bonding it to another film or paper having high heat resistance, and also to prevent curling.

In the image receiving medium of the present invention, the dyeing resin constituting the dye receiving layer is not particularly limited as long as it is a resin showing dyeability to a sublimable dye.
Examples thereof include polyester resins, vinyl chloride / vinyl acetate copolymer resins, acrylic resins and nylon resins. Among these, those having a resin cured product obtained by curing a vinyl chloride resin or a polyester resin with a curing agent such as an isocyanate compound as a main component have a good balance between dyeing property and releasability, and are particularly preferable. .

If desired, the dye-receptive layer may contain a release agent such as amino-modified silicone, epoxy-modified silicone, alkyd-modified silicone, or silica, titanium oxide, calcium carbide or the like. A white pigment may be included as a filler. In addition, the dye receiving layer may appropriately contain a surfactant, an ultraviolet absorber, an antioxidant and the like.

Further, in the image receiving medium of the present invention, an intermediate layer may be provided between the substrate and the dye receiving layer, a surface layer on the dye receiving layer, or a back layer on the lower surface of the substrate, if necessary. It can be provided by using a material, or can be subjected to surface treatment, heat and energy ray treatment.

In the sublimation type thermal transfer recording system, the image receiving medium of the present invention can obtain a uniform image without roughness even in a low density image portion, has high sensitivity and can obtain high image density even in a low energy application portion. it can. In particular, in the above-mentioned recording method by the n-fold mode method, the granular dye in the transfer layer of the recording medium is apt to transfer to the image receiving medium to cause graininess in the image, and the curable resin is used as the resin in the dye receiving layer of the image receiving medium. Since the sensitivity tends to be lowered because it is used favorably, when the image receiving medium of the present invention is applied to the system, excellent effects are exhibited.

The sublimation type thermal transfer system by the n-fold mode method records a sublimation type thermal transfer recording medium having a transfer layer containing a thermal sublimation dye and an image receiving medium having a dye receiving layer provided on a substrate. The transfer layer of the medium and the dye receiving layer of the image receiving medium are superposed so that they face each other, and the speed of the image receiving medium / the speed of the recording medium> 1 or the feed amount of the image receiving medium / the feed amount of the recording medium> 1 (that is, The speed of the image receiving medium is made faster than the speed of the recording medium), and heating printing is performed from the substrate side of the recording medium.

[0020]

EXAMPLES Next, the present invention will be described in more detail by way of examples. All parts shown below are based on weight.

Examples 1 and 2 and Comparative Examples 1 to 3 Using a bubble-containing plastic film shown in Table 1 as a substrate, the following [A liquid] was applied onto the substrate to give a thickness of 5 μm.
The dye receiving layer of m was formed to prepare a sublimation type image receiving medium for thermal transfer.

[Liquid A] Vinyl chloride / vinyl acetate copolymer 20 parts (trade name VYHH; Union Carbide Co.) alcohol modified silicone oil 2 parts (trade name SF8427; Toray Dow Corning Silicone Co.) toluene 40 parts Methyl ethyl ketone 40 Department

On the other hand, as a transfer recording medium of a heat sublimable dye, a silicone resin film having a thickness of about 1 μm as a back layer is used.
m) was provided on a PET film having a thickness of 6 μm, a transfer layer coating liquid [B liquid] having the following formulation was applied to a thickness of about 2 μm to obtain a transfer recording medium.

[Liquid B] Polyvinyl butyral resin (trade name BX-1; manufactured by Sekisui Chemical Co., Ltd.) 10 parts Thermal sublimation disperse dye for cyan (trade name Kayaset 714; manufactured by Nippon Kayaku Co., Ltd.) 6 parts Methyl ethyl ketone 45 parts Toluene 45 parts

The thus obtained transfer recording medium and image receiving medium are superposed so that the transfer layer of the transfer recording medium and the dye receiving layer of the image receiving medium face each other, and heating energy is changed from the back surface of the transfer recording medium by a thermal head. Then, the image was recorded. The recording density of the thermal head is 6 dots / mm.
The print output was 0.42 w / dot. The results are shown in Table 2.

[0026]

[Table 1]

[0027]

[Table 2] Note) The image densities 1 to 3 are the image densities of the respective gradations when the image of the gradation pattern is formed by changing the application time.

It can be seen from Table 1 that the image receiving medium of the present invention can obtain an image of higher density than the image receiving medium of the comparative example.

Examples 3 to 5 The polyester film used in Example 2 (trade name E6)
0) and the laminating film shown in Table 3 were used as a substrate, and an image receiving medium was prepared in the same manner as in Example 1 and image recording was carried out. An even and highly sensitive image was obtained. Further, as compared with the case of not laminating (Example 2), curling was reduced and the feeding was stable, so that there was no problem in continuous printing.

[0030]

[Table 3]

Example 6 Using the bubble-containing polyester / white polyester laminate of Example 3 as a substrate, the following [C liquid] was coated on the substrate, and an image receiving medium was prepared in the same manner as in Example 1.

[Liquid C] Vinyl Chloride / Vinyl Acetate / Vinyl Alcohol Copolymer 10 Parts (Brand Name VAGH; Union Carbide Co.) Isocyanate 5 Parts (Brand Name Coronate L; Nippon Polyurethane Co.) Alcohol Modified Silicone Oil 5 parts (trade name SF8427; manufactured by Toray Dow Corning Silicone) 0.5 parts epoxy modified silicone oil (product name SF8411; manufactured by Toray Dow Corning Silicone) toluene 40 parts methyl ethyl ketone 40 parts

On the other hand, as a transfer recording medium, an aromatic polyamide film having a thickness of 1 μm and having a silicone cured resin film on the back surface was applied to an aromatic polyamide film having a thickness of 8 μm.
Was applied to a thickness of about 3 μm using a wire bar to obtain a transfer recording medium.

[Liquid D] Sublimation dye 16 parts (trade name Kayaset Blue 714; manufactured by Nippon Kayaku Co., Ltd.) Polyvinyl butyral resin 7 parts (trade name BX-1, manufactured by Sekisui Chemical Co., Ltd.) Isocyanate 2 parts (trade name Coronate) L; manufactured by Nippon Polyurethane Co., Ltd.) Amino-modified silicone oil 1 part (trade name SF8417; manufactured by Toray Silicone) Epoxy-modified silicone oil 1 part (product name SF8411; manufactured by Toray Silicone) Toluene 70 parts Methyl ethyl ketone 70 parts

The obtained transfer recording medium and image receiving medium are superposed so that the transfer layer of the transfer recording medium and the dye receiving layer of the image receiving medium face each other, and the speed of the image receiving medium / the speed of the transfer recording medium =
Printing was performed with No. 7, but a uniform image was obtained with less image roughness due to surface irregularities of the transfer layer, and a highly sensitive image was obtained.

[0036]

The image receiving medium for sublimation type thermal transfer according to claim 1 is
Since the bubble-containing plastic film having the density D satisfying the formula 1 is used as the substrate, it is possible to obtain an image with excellent uniformity and high density.

An image receiving medium for sublimation type thermal transfer according to a second aspect is a laminate obtained by laminating a bubble-containing plastic film having the density D as a substrate and at least one plastic film or paper which is the same as or different from the film. Since it is used, strength and heat resistance can be improved and curling can be prevented.

In the image receiving medium for sublimation type thermal transfer of claim 3, since the dye receiving layer is composed mainly of the curable resin composition, the dyeing property and the releasability are well balanced, and A decrease in sensitivity can also be suppressed.

In the sublimation type thermal transfer recording method of the fourth aspect, since the image receiving medium is applied to the n-fold mode method, a very large effect is obtained particularly in the n-fold mode method which requires uniformity and sensitivity. Play.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an example of an image receiving medium for sublimation thermal transfer according to the present invention.

FIG. 2 is a schematic cross-sectional view showing another example of the image receiving medium for sublimation thermal transfer according to the present invention.

FIG. 3 is a schematic sectional view showing still another example of the image receiving medium for sublimation thermal transfer according to the present invention.

FIG. 4 is a schematic sectional view showing still another example of the image receiving medium for sublimation thermal transfer according to the present invention.

[Explanation of symbols]

 1 Bubble-containing plastic film 2 Dye receiving layer 3 Paper 4 Plastic film

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroki Kuboyama 1-3-6 Nakamagome, Ota-ku, Tokyo Stock company Ricoh Co., Ltd. (72) Inventor Yutaka Ariga 1-3-6 Nakamagome, Ota-ku, Tokyo Shares Company Ricoh

Claims (4)

[Claims] 1. An image receiving medium used in combination with a sublimation type thermal transfer recording medium having a transfer layer containing a heat sublimable dye, comprising at least a substrate and a dye receiving layer provided on the upper surface of the substrate. A sublimation type image receiving medium for thermal transfer characterized in that the substrate is composed of a bubble-containing plastic film having a density D satisfying the following formula 1. [Equation 1] (In the above formula, D ₀ represents the density of a plastic film containing the same material as that of the above-mentioned substrate and containing no bubbles.) 2. The sublimation type thermal transfer according to claim 1, wherein the substrate is formed by laminating a bubble-containing plastic film having the density D and at least one plastic film or paper which is the same as or different from the film. Image receiving medium. 3. The image receiving medium for sublimation thermal transfer according to claim 1, wherein the dye receiving layer is a layer containing a curable resin composition as a main component. 4. The recording medium and any one of claims 1 to 3.
And the transfer layer of the recording medium and the dye receiving layer of the image receiving medium are faced to each other, and the speed of the image receiving medium / the speed of the recording medium> 1 or the feed amount of the image receiving medium / the recording medium Sublimation type thermal transfer recording method, wherein heating printing is performed from the recording medium side under the condition that the feeding amount of the sheet is> 1.