JP3236670B2 - Dye receiving layer transfer sheet and composite thermal transfer sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dye-receiving layer transfer sheet and a composite thermal transfer sheet, and more particularly to a dye-receiving layer transfer sheet and a composite thermal transfer sheet capable of forming a high-quality color image by a thermal transfer system.

[0002]

2. Description of the Related Art Various thermal transfer methods are known in the art. Among them, a sublimable dye is used as a recording agent, and this is carried on a base film such as paper or plastic film to form a thermal transfer sheet. There have been proposed methods of forming various full-color images on an image receiving sheet such as paper or plastic film provided with a layer. In this case, a thermal head of a printer is used as a heating means, and a large number of color dots of three or four colors are transferred to the image receiving sheet by heating for a very short time, and a full-color image of the original is formed by the multicolor dots. That is to reproduce.

The image receiving sheet on which an image can be formed by the above method is limited to a dye-dyeing plastic sheet or a paper provided with a dye receiving layer in advance, and an image can be directly formed on ordinary plain paper. There is no problem. Of course,
If a dye receiving layer is formed on the surface of ordinary plain paper, image formation is possible, but this is generally costly. For example, postcards, memos, stationery, report paper It is difficult to apply to general ready-made image receiving sheets such as As a method for solving such a problem, when an image is to be formed on a ready-made image receiving sheet such as plain paper,
As a method for easily forming a dye receiving layer only in a necessary portion thereof, a dye receiving layer transfer sheet is known (for example,
JP-A-62-264994). As a method for further simplifying the operation, yellow, cyan, magenta and, if necessary, black dye layers are sequentially formed on the surface of the long base film, and the transfer dye is received on the same base film. A composite thermal transfer sheet is known, in which a layer is provided, a dye receiving layer is first transferred to an image receiving sheet, and then a dye of each color is transferred to the dye receiving layer to form a full color image.
Further, there has been proposed a composite thermal transfer sheet further provided with a protective layer for protecting the formed dye image in a plane-sequential manner.

[0004]

When the above-mentioned dye-receiving layer transfer sheet or composite thermal transfer sheet is prepared, the layer containing the dye-receiving layer is required to have good releasability.
Therefore, a release layer is often formed between the base film and the transferable dye receiving layer. When the dye receiving layer is transferred to the image receiving sheet by a thermal head or the like using such a dye receiving layer transfer sheet or a composite thermal transfer sheet, the release layer may be melted or melted due to a temperature change of the thermal head, heat storage in the printer, or the like. Softens and the release layer and the dye receiving layer fuse together,
The transferability of the dye receiving layer is reduced, or a part of the release layer is transferred to the transferred dye receiving layer surface, resulting in uneven density, missing or missing dots in an image formed on the dye receiving layer surface. There is a problem that occurs. In the case of a composite thermal transfer sheet provided with a dye layer and / or a transferable protective layer together with a transferable dye-receiving layer on a continuous base film, the dye-receiving layer and the protective layer are also transferred by a thermal head. Has become a very important issue. Therefore, an object of the present invention is to solve the above-mentioned conventional problems, and when transferring a dye receiving layer, a dye receiving layer in which the transferability of the dye receiving layer is good even by a temperature change of a thermal head or heat storage in a printer. A transfer sheet and a composite thermal transfer sheet are provided.

[0005]

The above object is achieved by the present invention described below. That is, in the present invention, a transferable dye-receiving layer that can be peeled off via a release layer is formed on one surface of a long base film, and the release layer has a functional group having a functional group.
A dye-receiving layer transfer sheet comprising a crosslinked product of a plastic resin with a polyisocyanate , and a transferable dye-receiving layer that is releasable with one or more color dye layers on one surface of a long base film. Are formed sequentially and the release layer is a polyisocyanate of a thermoplastic resin having a functional group.
A composite thermal transfer sheet comprising a crosslinked product of

[0006]

[ Function ] A release layer provided on a base film has a functional group.
When the dye receiving layer is transferred by forming it from a crosslinked product of a thermoplastic resin with a polyisocyanate , the transferability of the dye receiving layer is good even by a temperature change of a thermal head or heat storage in a printer. A layer transfer sheet and a composite thermal transfer sheet are provided.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in more detail with reference to preferred embodiments. The dye-receiving layer transfer sheet of the present invention has a release layer 2, a dye-receiving layer 3 and an adhesive provided on the surface of a long base film 1, as shown schematically in FIG. 1a. Layer 4 is provided, and the release layer 2 is a thermoplastic resin polyisocyanate having a functional group.
Characterized by comprising a crosslinked product of Another embodiment shown in FIG. 1b shows a case where an intermediate layer 7 is provided between the transferable dye receiving layer 3 and the adhesive layer 4 of FIG. 1a. 8 is a heat-resistant lubricating layer for the thermal head. The composite thermal transfer sheet of the present invention has a dye layer 5 of one color or a plurality of colors, for example, yellow (5Y), on one surface of the long base film 1 as shown schematically in FIG. , Magenta (5
M), cyan (5C) and black (B
k) a dye layer 5 (not shown), a release layer 2, a dye receiving layer 3, and an adhesive layer 4 provided on the surface of the base film 1, and a transferable protective layer 6 which may be provided as necessary. (And an adhesive layer 4 provided on the surface thereof) are provided face-to-face, and the release layer 2 is a polyisocyanate of a thermoplastic resin having a functional group.
Characterized by comprising a crosslinked product of Another embodiment shown in FIG. 3 is the dye receiving layer 3 and the adhesive layer 4 of FIG.
And a case where an intermediate layer 7 is provided between them. 8 is a heat-resistant lubricating layer for the thermal head. Another embodiment, shown in FIG. 4, is to replace the dye receiving layer area and the protective layer area of FIG.
This is an example in which the substrate is divided and one is a protective layer region and the other is a dye receiving layer region.

As the base film used in the present invention, the same base film as used in the conventional thermal transfer sheet can be used as it is, and other base films can be used without any particular limitation. Specific examples of preferred base film include, for example, glassine paper,
Thin paper such as condenser paper and paraffin paper, polyester, polypropylene, cellophane, polycarbonate, cellulose acetate, polyethylene, polyvinyl chloride, polystyrene, nylon, polyimide, polyvinylidene chloride,
Examples thereof include plastics such as ionomers and base films in which these are combined with the paper. The thickness of the base film can be appropriately changed depending on the material so that the strength and heat resistance are appropriate, but the thickness is preferably 3 to 100 μm.

In the dye receiving layer transfer sheet of the present invention,
Prior to the formation of the dye receiving layer 3 (or the protective layer 6), the release layer 2 is provided on the base film 1. Such a release layer has a functional group.
It consists polyisocyanates according crosslinked <br/> of thermoplastic resin having, as the thermoplastic resin having a government functional group, polyester resins, acrylic resins, polyvinyl acetal resins, cellulose resins . In the case of forming a peeling layer of a thermoplastic resin having these functional groups, optionally catalysts, viscosity modifiers, extender pigments, etc. are added. In a more preferred embodiment, the releasing property of the dye receiving layer can be further improved by adding a releasing agent such as a wax, a silicone wax, a silicone resin, a fluororesin or the like at the time of forming the releasing layer. The method for forming the release layer is the same as the method for forming the dye-receiving layer described below, coating the coating solution for the release layer on the base film, heating ,
Release location, it is possible to form a desired release layer by aging or the like, the thickness thereof is sufficient at about 0.5 to 5 [mu] m. or,
If a matte dye-receiving layer is desired after transfer, various particles can be included in the release layer, or the surface of the release layer on the dye-receiving layer side can be matted.

In the dye receiving layer transfer sheet of the present invention,
The dye receiving layer formed on the surface of the release layer is for receiving a sublimable dye transferred from the thermal transfer sheet after transfer to an arbitrary image receiving sheet and maintaining the formed image. Examples of the resin for forming the dye receiving layer include polyolefin resins such as polypropylene, polyvinyl chloride, vinyl chloride / vinyl acetate copolymer, halogenated polymers such as polyvinylidene chloride, polyvinyl acetate, and the like.
Vinyl polymers such as polyacrylester, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, polystyrene resins, polyamide resins, copolymer resins of olefins such as ethylene and propylene with other vinyl monomers, ionomers, and cellulose resins Cellulose-based resins such as acetate, polycarbonates and the like are mentioned, and particularly preferred are vinyl-based resins and polyester-based resins. Preferred release agents to be used by mixing with the above resins include silicone oil, phosphate ester surfactants, fluorine surfactants, etc., but silicone oil is preferred. As the silicone oil, epoxy-modified, alkyl-modified, amino-modified, carboxyl-modified, alcohol-modified, fluorine-modified,
Modified silicone oils such as alkyl aralkyl polyether-modified, epoxy / polyether-modified, and polyether-modified are preferred.

One or more release agents are used. The amount of the release agent is preferably 0.5 to 30 parts by weight based on 100 parts by weight of the resin for forming the dye receiving layer. If the addition amount is not satisfied, problems such as fusion of the thermal transfer sheet and the dye receiving layer or reduction in printing sensitivity may occur. By adding such a release agent to the dye-receiving layer, the release agent bleeds out on the surface of the dye-receiving layer after the transfer to form a release layer. The dye-receiving layer is formed by dissolving a resin obtained by adding a necessary additive such as a release agent to the above-described resin on one surface of the release layer, or dissolving the resin in an appropriate organic solvent or in an organic solvent or water. Dispersed dispersion,
For example, it is formed by applying and drying by a forming means such as a gravure printing method, a screen printing method, and a reverse roll coating method using a gravure plate. The dye receiving layer formed as described above may have any thickness, but generally has a thickness of 1 to 10 μm. Further, such a dye receiving layer is preferably a continuous coating, but may be formed as a discontinuous coating using a resin emulsion or a resin dispersion.

In the present invention, it is preferable to provide an adhesive layer on the surface of the dye receiving layer in order to improve the transferability of these layers. For these adhesive layers, any of conventionally known pressure-sensitive adhesives and heat-sensitive adhesives can be used, but it is more preferable to form the adhesive layer from a thermoplastic resin having a glass transition temperature of 50 ° C to 80 ° C. resin,
Vinyl chloride resin, vinyl chloride / vinyl acetate copolymer resin,
A resin having an appropriate glass transition temperature is selected from a resin having good adhesiveness at hot time such as a polyester resin, and the solution is applied and dried to form a layer having a thickness of preferably about 0.5 to 10 μm. I do. Further, in the present invention, an intermediate layer 7 can be provided between the dye receiving layer and the adhesive layer as shown in FIG. 1b. Examples of the material constituting the intermediate layer include polyurethane resin, acrylic resin, polyethylene resin, butadiene rubber, and epoxy resin. The thickness of the intermediate layer is 2 to 10 μm
The degree is preferred. The method for forming the intermediate layer may be the same as that for the dye receiving layer. White pigment in the adhesive layer and the intermediate layer,
Optical brighteners and / or air bubbles (or blowing agents) can be included. These white pigments and fluorescent whitening agents improve the whiteness of the dye-receiving layer after transfer, or mask the light yellow color of the paper as the image-receiving sheet. It has the function of imparting good cushioning properties to the layer. As a method of including these additives, a white pigment or the like may be included in the coating liquid used for forming each layer.

In the composite thermal transfer sheet of the present invention, a dye layer is formed on the surface of the above-mentioned base film at a predetermined interval in a plane-sequential manner. Such a dye layer is a layer in which a dye is supported by an arbitrary binder resin. As the dye to be used, any dye conventionally used in a thermal transfer sheet can be effectively used in the present invention, and is not particularly limited. For example, some preferred dyes include red dyes such as MS Red G, Macrolex Red Violet R, Ceres R
ed7B, Samaron Red HBSL, Resolin RedF3BS, etc., and as a yellow dye, holon brilliant yellow 6GL, PTY-52, macrolex yellow 6
G and the like, and examples of the blue dye include Kayaset Blue 714, Waxolin Blue AP-FW, Holon Brilliant Blue SR and MS Blue 100.

As the binder resin for supporting the dye as described above, any of conventionally known binder resins can be used. Preferred examples thereof include ethylcellulose, hydroxyethylcellulose, ethylhydroxycellulose, hydroxypropylcellulose, methylcellulose and acetate. Cellulose resins such as cellulose and cellulose acetate butyrate,
Polyvinyl alcohol, polyvinyl acetate, polyvinyl butyral, polyvinyl acetal, polyvinyl pyrrolidone, vinyl resins such as polyacrylamide, polyester and the like, among these, cellulose,
Acetal type, butyral type, polyester type and the like are preferred from the viewpoint of heat resistance, dye transferability and the like. Further, in the dye layer, various conventionally known additives may be included as necessary. Such a dye layer is preferably prepared by adding the above-mentioned sublimable dye, a binder resin and other optional components in an appropriate solvent and dissolving or dispersing each component to prepare a dye layer forming paint or ink. Is formed on the above-mentioned base film by applying and drying it in a plane-sequential manner. The dye layer thus formed has a thickness of 0.2 to 5.0 μm, preferably about 0.4 to 2.0 μm, and the sublimable dye in the dye layer has a thickness of 5 to 5% of the weight of the dye layer. Suitably it is present in an amount of up to 90% by weight, preferably 10 to 70% by weight. The transferable dye-receiving layer, which is formed on the surface of the base film in a surface-sequential manner with respect to the dye layer, is formed via a release layer as in the case of the dye-receiving layer transfer sheet, and is transferred to an arbitrary image receiving sheet. This is to receive the sublimable dye transferred from the thermal transfer sheet later and maintain the formed image.

The relationship between the transferable dye-receiving layer and the dye layer is not particularly limited. For example, as shown in FIGS. 2 and 3, one unit is composed of the dye-receiving layer → Y → M → C → Bk → protective layer. Although it is general, the present invention is not limited to this. For example, the example shown in FIG. 4 or another example may be used. The dyes of each hue are usually provided on the same area, but the transferable dye receiving layer (or protective layer) is transferred twice or more depending on the type of image receiving sheet and the durability required for the image. In some cases, it may be required to form a larger area. The method for forming the release layer, the transferable dye-receiving layer (or the protective layer) or the intermediate layer may be the same as that for the dye-receiving layer transfer sheet, except that the release layer and the intermediate layer are provided sequentially. The transferable protective layer can be formed in the same manner as the transferable dye-receiving layer as described above, but the formation of the intermediate layer is unnecessary, and the transferable protective layer allows the image to be observed through the layer. Therefore, it is necessary to be transparent or translucent. The forming material, forming method, thickness and the like of the protective layer and the adhesive layer formed on the surface thereof may be the same as those of the dye receiving layer.

The image receiving sheet for transferring the dye receiving layer and forming an image by using the dye receiving layer transfer sheet or the composite thermal transfer sheet as described above is not particularly limited. For example, plain paper, high quality paper, Any sheet such as tracing paper, plastic film, etc., and in terms of shape, cards, postcards, passports, stationery, report paper,
It may be any type of notebook, catalog, etc., and is particularly applicable to plain paper and rough paper having a rough surface. The transfer method of the dye receiving layer and the protective layer can be heated to a temperature at which the dye receiving layer or the adhesive layer is activated, such as a general printer with a thermal head for thermal transfer, a hot stamper for a transfer foil, a heat roll, etc. Any heating and pressurizing means may be used.
As a method for forming an image, any conventionally known means can be used. For example, by controlling a recording time by a recording device such as a thermal printer (for example, a video printer VY-100 manufactured by Hitachi, Ltd.),
By applying thermal energy of about 5 to 100 mJ / mm ² , the intended purpose can be sufficiently achieved.

[0017]

Next, the present invention will be described more specifically with reference to examples and comparative examples. In the following description, parts and% are based on weight unless otherwise specified. Example 1 The following coating liquid for a release layer was dried to 1.0 g / m ² on the surface of an easily-adhesive polyethylene terephthalate film (thickness: 6.0 μm, manufactured by Toray) having a heat-resistant lubricating layer formed on the back surface. Coating by gravure printing at a ratio, pre-drying with a drier, drying in an oven at 100 ° C. for 30 minutes to form a release layer, and further coating the following dye receiving layer coating solution on the surface by gravure printing It was applied at a rate of 3.0 g / m ² when dried, and was temporarily dried with a drier, and then dried in an oven at 100 ° C. for 30 minutes to form a dye receiving layer. Further, the surface was coated with the adhesive layer coating solution described below at a rate of 3.0 g / m ² and dried in the same manner to form an adhesive layer, thereby forming a dye-receiving layer transfer sheet of the present invention. Obtained.

[0018]

[0019]

Example 2 The same coating liquid for a release layer as in Example 1 having a width of 60 cm and a gap was applied to the surface of an easily adhesive polyethylene terephthalate film (6.0 μm thick, manufactured by Toray) having a heat-resistant lubricating layer formed on the back surface. A release layer was formed at 90 cm in the same manner as in Example 1, and a dye receiving layer and (adhesive layer) and a protective layer (and adhesive layer) were formed thereon. The dye-receiving layer and the protective layer were coated with a coating solution for the dye-receiving layer having the following composition by gravure printing at a rate of 3.0 g / m ² when dried, temporarily dried with a drier, and then dried in an oven at 100 ° C. The adhesive layer was formed by coating and drying at a rate of 3.0 g / m ² on the dye-receiving layer surface and the protective layer surface in the same manner using the following adhesive solution.

[0021] Subsequently, an ink for a dye layer having the following composition was prepared, and a width of 30 cm was applied to the surface of the base film on which the dye receiving layer was not formed.
Each was applied and dried by a gravure coater so that the dry coating amount became 1.0 g / m ² , to obtain a composite thermal transfer sheet of the present invention.

[0022] In the same manner, the yellow thermal transfer sheet was treated with a yellow disperse dye (Macrolex Yellow 6G, manufactured by Bayer, CIDisper).
se Yellow 201) and a magenta thermal transfer sheet was formed using a magenta disperse dye (CIDisperse Red 60).

[0023]

[0024] Comparative Example 1 Example a release layer aqueous urethane polymer in 2 (Bonn index 1670 (N), Dainippon Ink) composite thermal transfer sheet of Comparative Example in the same manner as in Example 2 except that it was formed from I got

Use Example 1 The dye-receiving layer transfer sheet of Example 1 was superimposed on plain paper, and the dye-receiving layer was transferred using a thermal head. Next, a cyan thermal transfer sheet is superimposed on the surface of the dye receiving layer, and an output of 1 W / dot,
Pulse width 0.3 to 0.45 msec. Printing was performed on the entire surface of the dye receiving layer under the conditions of a dot density of 3 dots / mm to form a Betasian image. Observation of the transferability (at 20 ° C. and 40 ° C. ambient temperature) and image quality of the dye receiving layer during the image formation described above gave the results shown in Table 1 below. Use Example 2 Using the composite thermal transfer sheets of Example 2 and Comparative Example 1 , an image was formed in the same manner as in Use Example 1 and evaluated in the same manner. The results shown in Table 1 below were obtained.

[0026]

[Table 1]

[0027]

According to the present invention as described above, a release layer provided on a base film is formed of a thermoplastic resin having a functional group.
When the dye-receiving layer is transferred by forming from a crosslinked product of cyanate, the transferability of the dye-receiving layer is good even by the temperature change of the thermal head or the heat storage in the printer, and the dye-receiving layer transfer sheet and the composite thermal transfer. A sheet is provided.

[Brief description of the drawings]

FIG. 1 is a diagram schematically illustrating a cross section of a dye receiving layer transfer sheet of the present invention.

FIG. 2 is a diagram schematically illustrating a cross section of the composite thermal transfer sheet of the present invention.

FIG. 3 is a diagram schematically illustrating a cross section of the composite thermal transfer sheet of the present invention.

FIG. 4 is a diagram schematically illustrating a cross section of the composite thermal transfer sheet of the present invention.

[Explanation of symbols]

 1: base film 2: release layer 3: dye receiving layer 4: adhesive layer 5: dye layer 6: protective layer 7: intermediate layer 8: heat-resistant lubricating layer

Continuation of the front page (56) References JP-A-4-135793 (JP, A) JP-A-1-160682 (JP, A) JP-A-1-122485 (JP, A) JP-A-4-168091 (JP) , A) JP-A-62-264994 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41M 5/38-5/40

Claims (4)

(57) [Claims] 1. A long-strength base film having a transferable dye-receiving layer formed on one side thereof via a release layer, wherein said release layer is a polyisocyanate of a thermoplastic resin having a functional group.
A dye-receiving layer transfer sheet, comprising a crosslinked product of a dye. 2. A long-strength base film having a dye layer of one or more colors and a peelable transferable dye-receiving layer formed on one surface of the long base film in a sequential manner, wherein the release layer has a functional group. Having thermoplastic
A composite thermal transfer sheet comprising a crosslinked product of a hydrophilic resin with a polyisocyanate . 3. The composite thermal transfer sheet according to claim 2 , further comprising a transferable protective layer provided in a face-sequential manner. 4. The transferable dye-receiving layer includes an intermediate layer and an adhesive layer, and at least one of these layers is at least one selected from the group consisting of a white pigment, a fluorescent whitening agent, and a bubble (or a foaming agent). 3. The composite thermal transfer sheet according to claim 2 , comprising a seed.