JPH04133793A - Thermal transfer image formation - Google Patents

Abstract

PURPOSE:To provide a sublimable transfer image of high quality at a necessary spot on any given medium for transfer having a non-smooth surface by forming an image on a dye receptive layer formed in freely peel-off manner on one side of a base film using sublimation transfer technique and transferring the dye receptive layer to a medium for transfer. CONSTITUTION:A receptive layer transfer sheet A with a dye receptive layer 3 formed on one side of a base film, if necessary, through a peel-off layer, in freely peel-off manner is placed over a sublimable, thermal transfer sheet B. The back of the thermal transfer sheet B is heated using a thermal head to form a specified image on the receptive layer 3. Next, the receptive layer 3 having an image 5 is placed over any given medium for transfer C, and the back of the receptive layer transfer sheet A is heated using a heating device 4 such as a thermal head. Then the receptive layer 3 having an image 5 is transferred to the given medium for transfer C. Prior to the formation of the receptive layer, a peel-off layer is formed on the surface of a base film. The peel-off layer is formed using waxes, silicone wax, silicone resin, fluorine resin, acrylic resin, etc., as peel-off materials. The dye receptive layer receives a sublimable dye which migrates from the thermal transfer sheet and maintains a formed image in good condition.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a method for forming a thermal transfer image, and more specifically, to a method for forming a high-quality sublimation transfer image on a desired location of an arbitrary transfer material whose surface does not need to be smooth. The present invention relates to a method for forming a thermal transfer image that can be applied.

(Prior art and its problems) Conventionally, various thermal transfer methods are known, but among them, a thermal transfer sheet is produced by using a sublimable dye as a recording agent and supporting it on a base film such as paper or plastic film. year,
Various methods have been proposed for forming full-color images on paper or plastic films provided with dye-receiving layers. In this case, the printer's thermal head is used as the heating means, and a large number of three or four color dots are transferred to the thermal transfer image receiving sheet by extremely short heating, and the multicolor dots create a full-color image of the original. It is intended to reproduce.

The images formed in this way are very clear because the coloring material used is dye, and they have excellent transparency, so the images obtained have excellent intermediate color reproducibility and gradation, and are It is possible to form high-quality images that are similar to images produced by offset printing or gravure printing, and comparable to full-color photographic images.

However, image-receiving sheets on which images can be formed using the above method are limited to dye-dyeable plastic sheets or paper with a dye-receiving layer provided in advance, and images cannot be directly formed on general plain paper. There is a problem. Of course,
It is possible to form images on ordinary plain paper if a receptive layer is formed on its surface, but this is expensive and can be used on postcards, memos, stationery, report paper, etc. It is difficult to apply this method to general ready-made recording paper such as.

To solve these problems, a receptor layer transfer sheet is known as a method to easily form a dye receptor layer only in the necessary areas when trying to form an image on a ready-made product such as plain paper. (For example, Japanese Patent Application Laid-Open No. 62-26499
(See Publication No. 4).

However, even if the receptor layer is transferred to paper or the like having poor surface smoothness as described above, the surface of the transferred receptor layer is not sufficiently smooth due to the rough texture of the paper. When an image is formed by a sublimation transfer method, there is a problem that the adhesion between the thermal transfer sheet and the receptor layer is poor, and the formed image has white spots and chips.

Therefore, an object of the present invention is to provide a thermal transfer image forming method that can apply a high-quality sublimation transfer image to a necessary location on any transfer material whose surface does not need to be smooth.

(Means for solving problems) The above objects are achieved by the present invention as described below.

That is, in the present invention, an image is formed on a dye-receiving layer removably provided on one side of a base film by a sublimation transfer method,
This thermal transfer image forming method is characterized in that the dye-receiving layer having the above image is then transferred to a transfer material.

(Function) By forming an image on the dye-receiving layer of the receiver 1 transfer sheet by a sublimation transfer method, and then transferring the dye-receiving layer having the image to the transfer material, any transfer material whose surface is not smooth can be formed. High-quality sublimation transfer images can be applied to the required locations on the material.

(Preferred Embodiments) Next, the present invention will be explained in more detail by citing preferred embodiments.

The method of the present invention consists of a receptor layer transfer sheet A and a sublimation thermal transfer sheet B, in which a dye receptor layer 3 is releasably provided on one side of a base film 1 via a release layer 2 as required, as shown in the first diagram. from the back of thermal transfer sheet B to thermal head 4.
In order to form a desired image 5 on the receiving layer 3 by heating the first
In Figure a), the receiving layer 3 having the image 5 formed in this way is then placed on an arbitrary transfer material C, and heated from the back side of the receiving layer transfer sheet A by a heating means 4 such as a thermal head.
In a preferred embodiment of the present invention, as shown in the second figure,
After the image is formed as shown in FIG. 1a, and before being transferred to the transfer material C, a blocking layer 6 is formed on the image forming surface of the receptor layer 3, as shown in FIG. 2b.
), and by transferring this to the transfer material C (FIG. 2C), it is possible to more easily apply an image even to the transfer material C with a rough layer.

Further, the example shown in the third figure is an example in which the stopper layer 6 is formed in advance in the image forming area of the transfer material C, and similar effects are achieved.

The receiving layer transfer sheet used in the present invention is known per se, and as shown in the first figure, a dye receiving layer 3 is provided on one side of a base film 1 so as to be releasable via a peeling layer 2 if necessary. It is something that

As the above-mentioned base film, the same base film used for conventional thermal transfer sheets can be used as is, and other materials can also be used.
There are no particular restrictions.

Specific examples of preferred base films include thin paper such as glassine paper, capacitor paper, paraffin paper, polyester, polypropylene, cellophane, polycarbonate, cellulose acetate, polyethylene, polyvinyl chloride,
Examples include plastics such as polystyrene, nylon, polyimide, polyvinylidene chloride, and ionomer, and base films made of composites of these and the paper.

The thickness of this base film can be changed as appropriate depending on the material so that its strength, heat resistance, etc. are appropriate, but the thickness is preferably 3 to 100 μm.

It is preferable to form a release layer on the surface of the base film prior to forming the receptor layer. Such a peeling layer is made of wax,
It is formed from a release agent such as silicone wax, silicone resin, fluororesin, or acrylic resin. The formation method may be the same as the method for forming the receiving layer described later, and the thickness thereof is 0.5 to 5 μm.
It is enough. If a matte receiving layer is desired after transfer, the surface may be made matte by incorporating various particles into the release layer or by using a base film whose surface on the release layer side is matt-treated. I can do it. Of course, if the base film as described above has appropriate releasability, it is not necessary to form a release layer.

The dye-receiving layer formed on the surface of the base film is for receiving the sublimable dye transferred from the thermal transfer sheet and maintaining the formed image.

Examples of the resin for forming the dye-receiving layer include polyolefin resins such as polypropylene, halogenated polymers such as polyvinyl chloride and polyvinylidene chloride, vinyl polymers such as polyvinyl acetate and polyacrylic ester,
Polyester resins such as polyethylene terephthalate and polybutylene terephthalate, polystyrene resins, polyamide resins, copolymer resins of olefins such as ethylene and propylene and other vinyl monomers, ionomers, cellulose resins such as cellulose diacetate, polycarbonates Among them, vinyl resins and polyester resins are particularly preferred.

Particularly preferred resins in the present invention have a degree of polymerization of 3.
50 or less vinyl chloride/vinyl acetate copolymer. If the degree of polymerization exceeds 350, the film strength of the receptor layer is too high, and when attempting to transfer a finely patterned receptor layer, accurate transfer may not be possible, and the edges of the transfer receptor layer may become jagged or the transfer may be difficult. This may result in defects. A particularly preferable range of the degree of polymerization is 150 to 350, with a degree of polymerization of 15
If it is less than 0, the strength of the film after transfer will be insufficient, causing problems such as sticking to the dye layer of the thermal transfer sheet during dye transfer and the receiving layer being taken by the dye layer.

It is preferable to mix a mold release agent with the above resin, and examples of preferred mold release agents include silicone oil, phosphate ester surfactant, fluorine surfactant, and the like, with silicone oil being preferred. As the silicone oil, modified silicone oils such as epoxy-modified, alkyl-modified, amino-modified, carboxyl-modified, alcohol-modified, fluorine-modified, alkylaralkyl polyether-modified, epoxy-polyether-modified, and polyether-modified silicone oils are desirable.

The amount of the release agent added is preferably 0.2 to 5 parts by weight per 100 parts by weight of the dye-receiving layer forming resin. If the addition amount does not fall within this range, problems such as fusion between the thermal transfer sheet and the dye-receiving layer or a decrease in printing sensitivity may occur. Furthermore, if the amount added exceeds the above range, the adhesion of the image-formed receptor layer to the transferred material will be insufficient.

The receiving layer is prepared by dissolving the above-mentioned resin with necessary additives such as a mold release agent on one side of the base film in a suitable solvent, or in an organic solvent or water. It is formed by applying and drying the dispersed dispersion using a forming method such as a gravure printing method, a screen printing method, or a reverse roll coating method using a gravure plate.

When forming the dye-receiving layer, titanium oxide, zinc oxide, kaolin, etc. Pigments and fillers such as clay, calcium carbonate, and finely powdered silica can be added.

The dye-receiving layer formed as described above may have any thickness, but the thickness in question is 1 to 50 μm. Although such a dye-receiving layer is preferably a continuous coating, it may also be formed as a discontinuous coating using a resin emulsion or resin dispersion.

The sublimation type thermal transfer sheet used in the present invention itself is well known, and any conventionally known sublimation type thermal transfer sheet can be used in the present invention.

Further, as the means for applying thermal energy during image formation, any conventionally known means can be used, such as a thermal printer (for example, Video Printer V manufactured by Hitachi, Ltd.).
By controlling the recording time using a recording device such as Y-100), the intended purpose can be fully achieved by applying thermal energy of about 5 to 100 mJ/mrrr. However, in the method of the present invention, the final image obtained is a mirror image of the normal image, so it is preferable to form characters, symbols, etc. in advance as reverse images.

Although the method for forming the upper layer used in the preferred embodiment of the present invention is not particularly limited, chlorine is added to the surface of the base film 1 such as that used in the above-mentioned receptor layer transfer sheet via a release layer (not shown) as necessary. polypropylene, polyurethane,
A transfer layer 6 is formed in the same manner as the receiving layer by blending an extender pigment, a white pigment, etc. with a relatively soft resin such as vinyl chloride/vinyl acetate copolymer, polyester, or acrylic resin,
It is preferable to form this top layer transfer layer 6 by transferring it to the surface of the image-formed receptor layer 3 or the transfer area of the transfer material C (see Figures 2 and 3).

The above sealing layer is preferably formed to have a thickness of about 05 to 10 μm.

The transfer material used in the method of the present invention is not particularly limited, and may be any sheet such as plain paper, high-quality paper, tracing vapor, or plastic film. Any paper such as letter paper, report paper, notebook, catalog, etc. may be used, and it is particularly applicable to plain paper or rough paper with a rough surface.

The image-formed receptor layer can be transferred using any printer that can be heated to a temperature that activates the adhesive layer, such as a general printer equipped with a thermal head for thermal transfer, or a hot stamper 1 heat roll for transfer foil. A heating and pressurizing means may also be used.

(Example) Next, the present invention will be explained in more detail by giving examples and comparative examples. In the text, parts or percentages are based on weight unless otherwise specified.

Example 1 A release layer coating solution having the following composition was applied to the other side of a 6 μm thick polyester film (trade name "Lumirror", manufactured by Toshi ■) which had a heat-resistant back layer on one side. A release layer was formed by coating and drying at a ratio of 0 g/r&.

Polymethyl methacrylate resin (manufactured by Mitsubishi Rayon Co., Ltd., B
R-83) 100 parts methyl ethyl ketone 500 parts Next, apply a coating solution for the receptor layer having the following composition on the surface of the release layer using a bar coater when dry.
．． 0g/rr? A dye-receiving layer was formed by applying the dye in a proportion of 100 to 200, and drying with a dryer to obtain a dye-receiving layer transfer sheet.

Vinyl chloride/vinyl acetate copolymer (VYHD, manufactured by Union Carbide Co., Ltd., degree of polymerization 340) 100 parts Amino-modified silicone (KS-343, manufactured by Shin-Etsu Chemical Co., Ltd.)
1 part epoxy modified silicone (KF-393, manufactured by Shin-Etsu Chemical Co., Ltd.)
1 part methyl ethyl ketone
500 parts Next, the following ink composition for forming a dye layer was applied to the surface of a 6 μm thick polyethylene terephthalate film, which had been heat-resistant treated on the back side of the surface on which the dye layer is to be formed, as a base film to a dry thickness of 1. A thermal transfer sheet used in the present invention was obtained by coating and drying by gravure printing so as to obtain og/rrr.

8> Ink polishing product Kayaset Blue 14 (Nippon Kayaku Co., Ltd., C, I Solvent Blue 63) 5.50 parts Polyvinyl butyral resin (Eslec BX-1) 3.00 parts Methyl ethyl ketone 22.54 parts Toluene 68.18 parts Above The receiving layer transfer sheet and the above thermal transfer sheet are overlapped with the dye layer and the receiving layer facing each other, and a head applied voltage of 12.0 is applied from the back side of the thermal transfer sheet using a thermal head (KMT-85-6, MPD2). ■, Applied pulse width 16, 0 m5
Step pattern that sequentially decreases from ec, /1ine to IIIsec, 61ine/mm in the sub-scanning direction (
A cyan image was formed by thermal head recording under conditions of 33.3 m5 ec, /1 ine).

Next, copy paper was placed on the image surface, and the image receiving sheet was heated from the back side with a thermal head to transfer the image together with the receiving layer onto the copy paper.

Example 2 A hot stamper was used in place of the thermal head in Example 1 to transfer the image-formed receptor layer onto copy paper.

Example 3 As the base resin for the receiving layer in Example 1, vinyl chloride/vinyl acetate copolymer f#1ooOAs, manufactured by Denki Kagaku Kogyo ■, average degree of polymerization 320) was used, and the rest were as in Example 1.
The image was transferred to copy paper in the same manner.

Example 4 The following coating method was used as the coating solution for the receptor layer in Example 1, and a cyan image of the receptor layer was formed in the same manner.

100 parts of vinyl chloride/vinyl acetate copolymer (#1000AS, manufactured by Denki Kagaku Kogyo ■, average degree of polymerization 320), amino-modified silicone (KS-343, manufactured by Shin-Etsu Chemical @)
2-part epoxy modified silicone (KF-393, manufactured by Shin-Etsu Chemical Co., Ltd.)
2 parts methyl ethyl ketone 5
00 parts Next, a sealing layer (thickness: 5 LL) having the following composition was applied to the image surface.
m) was formed by transfer.

■ Top 1 ■ Chlorinated polypropylene (manufactured by Toyo Kasei Kogyo Co., Ltd., Birdren 15LBP) 100 parts White pigment (manufactured by Tochem Products ■, TCA 888) 200 parts Polyester resin (manufactured by Toyobo ■, Byron 200)
50 copies Next, in the same manner as in Example 1, the image-formed receptor layer was transferred onto copy paper.

Example 5 The receiving layer on which the image was formed was transferred in the same manner as in Example 1, except that the sealing layer was transferred to the copy paper in Example 4.

Example 6 When forming the thermal transfer sheet in Example 1, the dye layer and the sealing layer were alternately formed each with a width of 30 cm, and after the cyan image was formed, the sealing layer was transferred and formed on the entire surface. The image-formed receptor layer was transferred in the same manner as in Example 1.

Example 7 In forming the receptor layer transfer sheet in Example 1, the receptor layer and the blocking layer were alternately formed each with a width of 30 cm, and the blocking layer was first transferred to the image forming area of the copy paper, while the blocking layer was transferred to the image forming area of the copy paper. A cyan image was formed on the receiving layer, and this was transferred onto the sealing layer.

Example 8 As the base resin of the receptor layer in Example 1, vinyl chloride/vinyl acetate copolymer (#1000A, manufactured by 'Denki Kagaku Kogyo ■, average degree of polymerization 430) was used, and the rest were the same as in Example 1.
The image was transferred to copy paper in the same manner.

Example 9 The amount of silicone mold release agent in Example 1 was changed to 0 and 0, respectively.
The image was transferred to copy paper in the same manner as in Example 1 except that the amount was changed to 0.1% in 5% increments.

Example 10 An image was transferred to copy paper in the same manner as in Example 1, except that the amount of the silicone mold release agent in Example 1 was changed to 4% for each, for a total of 8%.

Comparative Example 1 A receptor layer coating liquid having the following composition was applied to the surface of a 25 μm thick polyester film (product name: R Lumirror, manufactured by Toshi) with a heat-resistant back layer on the back using a bar coater when dry. 3.0g/rr? A dye-receiving layer was formed by coating and drying with a dryer.

Tachigo Toyosato E2 1 plate Reduced vinyl chloride/vinyl acetate copolymer (VYHD, manufactured by Union Carbide, degree of polymerization 340) 100 parts Amino-modified silicone (KS-343, manufactured by Shin-Etsu Chemical Co., Ltd.)
5-part epoxy modified silicone (KF-393, manufactured by Shin-Etsu Chemical Co., Ltd.)
5 parts methyl ethyl ketone
500 parts of a coating solution for an adhesive layer having the following composition was applied to the surface of the receptor layer at a dry rate of 3.0 g/rrl' and dried to form an adhesive layer.

Skin bean I Satoza Futama polymedyl methacrylate resin (manufactured by Mitsubishi Rayon ■, B
R-1,06) 100 parts methyl ethyl ketone/toluene 500 parts The receptor layer was transferred from the obtained receptor layer transfer sheet to copy paper, and the following Example 1 was prepared.
A cyan image was formed in the same manner.

When forming images in the above Examples and Comparative Examples, the releasability between the thermal transfer sheet and the receptor layer, white spots in the image, image clarity, foil tearability during receptor layer transfer, and adhesion to copy paper were evaluated. The results shown in Table 1 below were obtained.

(Hereinafter referred to as blank space) According to the present invention as described above, an image is formed on the dye receiving layer of the receiving layer transfer sheet by a sublimation transfer method, and then the image is formed on the transfer material. By transferring the dye-receiving layer, a high-quality sublimation transfer image can be applied to the required location of any transfer material whose surface is not smooth.

[Brief explanation of drawings]

1 to 3 are views schematically explaining the method of the present invention. Base film 2: Release layer 3: Receiving layer 4: Thermal head 5: Image
6: Blocking layer A: Receptive transfer sheet B: Thermal transfer sheet C: Transferred material Patent applicant To Dai Nippon Printing Co., Ltd.? - Figure 2 (a) fb) Figure 2 (δ) (b) (C)

Claims (1)

[Scope of Claims] (1) An image is formed on a dye-receiving layer releasably provided on one surface of a base film by a sublimation transfer method, and then the dye-receiving layer having the image is transferred to a transfer material. A thermal transfer image forming method characterized by transferring. (2) The thermal transfer image forming method according to claim 1, wherein a sealing layer is formed on the image surface after the image is formed. (3) The thermal transfer image forming method according to claim 1, wherein a sealing layer is formed in the transfer area of the transfer material. (4) The thermal transfer image forming method according to claim 1, wherein the receiving layer comprises a vinyl chloride/vinyl acetate copolymer having an average degree of polymerization of 350 or less. (5) The thermal transfer image forming method according to claim 1, wherein the receiving layer contains a release agent, and the amount of the release agent is in the range of 0.2 to 5% by weight per 100 parts by weight of the resin forming the receiving layer.