JPH04197794A - Thermal transfer and its device - Google Patents

Abstract

PURPOSE:To enable formation of a high-quality color image without forming a detection mark separately by providing a single-or multi-color dye layers and one or plural separable white dye-receptive layers, in sequential surface order, on one surface of a long base film of a thermal transfer sheet and detecting the dye-receptive layer with the reflection or shielding of a detection light using a white-receptive layer. CONSTITUTION:A thermal transfer sheet A consists of a single-or multi-color dye layers 2Y, 2M, 2C and one or plural peel-off white dye-receptive layers 3 formed, in sequential surface order, on one surface of a long base film 1, and further, a transferable protecting layer 4, if necessary. The dye-receptive layer 3 is composed of white pigment added to such an extent that it becomes opaque, and an adhesive layer formed on the surface. If the thermal transfer sheet A is attached to a printer having a light projector 6 and a light receiving sensor 7 on one end and an image is thermally transferred, a detection light 8 is reflected by the dye-receptive layer 3 and received by the light receiving sensor 7 as the sheet runs, and the detection light 8 is not detected at the dye layer 2 or the protecting layer 4. If the light projector 6 and the light receiving sensor 7 are installed with the thermal transfer sheet A sandwiched in between, the dye-receptive layer 3 is detected when the detection light is not detected.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a thermal transfer method and apparatus, and more particularly to a thermal transfer method and apparatus capable of forming high-quality color images by a thermal transfer method.

(Prior art and its problems) Conventionally, various thermal transfer methods are known, but among them, thermal transfer is carried out by using a sublimable dye as a recording agent and supporting it on a base film such as paper or plastic film. As a sheet,
Various methods have been proposed for forming full-color images on image-receiving sheets such as paper and plastic films provided with dye-receiving layers.

In this case, the printer's thermal head is used as a heating means, and by heating in an extremely short time, three or four colors can be printed.
A large number of colored dots are transferred to an image receiving sheet, and a full-color image of an original is reproduced using the multicolored colored dots.

The thermal transfer sheet used in the above method has yellow, cyan, magenta and, if necessary, black dye layers formed sequentially on the surface of a long base film, and also has dye receptivity. When forming an image on an image-receiving sheet, a transfer-receptive layer is further provided on the surface of the same base film, and the receptor layer is first transferred to the image-receiver sheet, and then dyes of each color are transferred to the receptor layer to form a full-color image. There are known thermal transfer methods for forming.

In order to form a color image with a printer using these thermal transfer sheets, thermal transfer is performed on the image receiving sheet in a predetermined order, for example, a dye receiving layer, yellow, magenta, cyan, and black; Since it is necessary for the printer to detect the type of layer present in the printed area, a detection mark having such a function is usually formed in some area of the thermal transfer sheet.

As a method for causing a printer to detect such a detection mark, a method as shown in FIGS. 4 and 5 is used.

That is, in the case shown in the fourth figure, a light projector 6 is provided inside the printer, and a light receiving sensor 7 is installed on the opposite side of the thermal transfer sheet A, so that when the thermal transfer sheet A moves, the light is present on the thermal transfer sheet A. It is detected that the detection light 8 of the light projector 6 is partially blocked by the black light-absorbing detection mark 5, and the position of the thermal transfer sheet A and the hue of the dye layer are determined.

The method shown in FIG. 5 is a method in which a light projector 6 and a light receiving sensor 7 are provided on one side of a thermal transfer sheet A having a similar detection mark 5, and a reflector 10 is provided on the other side, and the presence or absence of reflected light 9 is determined. The position and hue of the thermal transfer sheet A are detected.

However, in the above method, it is necessary to separately form a different detection mark for each color region, which poses a big problem in terms of manufacturing process and cost.

Therefore, an object of the present invention is to solve the above-mentioned conventional problems,
An object of the present invention is to provide a thermal transfer method and a thermal transfer device capable of forming a high-quality color image without separately forming a detection mark.

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

That is, the present invention provides a thermal transfer method in which an image receiving sheet and a thermal transfer sheet are overlapped in a thermal transfer device, and heat is applied from the back side of the thermal transfer sheet to transfer a dye to the image receiving sheet. A dye layer of one color or multiple colors and one or more removable white dye-receiving layers are sequentially provided on one side, and detect light from a projector installed in the thermal transfer device. A thermal transfer method characterized by causing a thermal transfer device to detect the receptor layer by reflecting or blocking the white receptor layer, an image receiving sheet, a conveyance means therefor, a thermal transfer sheet, a conveyance means therefor, a heat application means, a projector, and In a thermal transfer device having a detection means consisting of a light receiver, the thermal transfer sheet has a dye layer of one or more colors on one side of a long base film and one or more peelable white dye receptors. The white receptor layer reflects or blocks detection light from a projector provided in the thermal transfer device, thereby causing the thermal transfer device to detect the receptor layer. This is a thermal transfer device.

(Function) By making the dye receiving layer white and opaque, the receiving layer can also be used as a detection mark, and there is no need to specially form a detection mark.

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

The thermal transfer sheet A used in the present invention and which mainly characterizes the present invention has a dye layer of one color or a plurality of colors on one side of a long base film l, as shown schematically in its cross section in FIG. ,
For example, yellow (Y), magenta (M), cyan (C)
) and, if necessary, a black (not shown) dye layer and one or more peelable white dye-receiving layers 3 are sequentially provided, and a transferable protective layer 4 is further formed if necessary. has been done.

The base film used in the thermal transfer sheet, the dye layers of each color, and the method of forming them are not particularly limited as long as they are based on conventionally known methods.

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

The dye-receiving layer is provided in plane order with respect to the dye layer. The relationship with the dye layer is not particularly limited, but for example, the receiving layer ==
b Y = 6 M = 6 C) Bk) Order of receptive layers, receptive layer in receptive layer -> Y = b M = b C-b 7
The order of the receptive layer in the 3k medium receptive layer is as follows: receptive layer = 5Y <receptive Ill -> M-0 receptive layer φC-b receptive layer) Bk) receptive layer.

It is preferable to form a release layer on the surface of the base film prior to forming the receptor layer. Its thickness is 0.01~5μm
It is enough.

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.

The receptor layer is prepared by dissolving a resin such as the one described above with a white pigment such as titane oxide or zinc oxide and other necessary additives in an appropriate organic solvent on one side of the base film. Alternatively, by applying and drying a dispersion in an organic solvent or water by a forming method such as gravure printing, screen printing, or reverse roll coating using a gravure plate, 0, 5~10μ
It is formed to a thickness of m.

In this case, it is important to add the white pigment to an extent that makes the receptor layer opaque, that is, to make a clear difference in translucency compared to the dye layer (and the protective layer, which will be described later), so that enough light can be detected. This is to reflect or block the light. For this purpose, the white pigment is preferably added in an amount of 1 to 200 parts by weight per 100 parts by weight of the receptor layer forming resin.

Furthermore, it is preferable to provide an adhesive layer on the surface of the above-mentioned receptor layer in order to improve the transferability of these layers. These adhesive layers are formed by coating and drying a solution of a resin with good heat adhesion, such as polyamide resin, acrylic resin, vinyl chloride resin, vinyl chloride/vinyl acetate copolymer resin, polyester resin, etc. , preferably 0.
It is formed to have a thickness of about 5 to 20 μm.

Furthermore, in the present invention, an intermediate layer can be provided between the receptor layer and the adhesive layer. 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 preferably about 2 to 10 μm. The method for forming the intermediate layer may be the same as that for the above-mentioned receptor layer.

A white pigment may be added to the adhesive layer and/or the intermediate layer as described above, and in this case, the receiving layer does not need to contain the white pigment.

Further, in a preferred embodiment of the present invention, the protective layer 4 can be provided in sequential order following the dye layer.

The protective layer 4 is made of various resins having excellent abrasion resistance, chemical resistance, transparency, hardness, etc., such as polyester resins, polystyrene resins, acrylic resins, polyurethane resins, acrylic urethane resins, silicone-modified resins of these resins, and Mixtures of these resins, etc. may be mentioned. The thickness of the protective layer 4 is preferably about 0.1 to 20 am.

Furthermore, in order to improve the transferability of these layers, a heat-sensitive adhesive layer can be formed on the surface of the above-mentioned protective layer, preferably with a thickness of about 0.1 to 10 μm, in the same manner as described above. .

The image-receiving sheet on which an image is formed using the above-mentioned thermal transfer sheet is not particularly limited, and may be any sheet such as plain paper, high-quality paper, tracing paper, or plastic film. , cards, postcards,
It can be used for passports, stationery, report paper, notebooks, catalogs, etc., and is particularly applicable to plain paper and rough paper with a rough surface.

The receiving layer or protective layer can be transferred using a general printer equipped with a thermal head for thermal transfer, a hot stamp bar 1 heat roll for transfer foil, etc., which can be heated to a temperature that activates the receiving layer or adhesive layer. Any heating and pressurizing means may be used.

In addition, any conventionally known means can be used to form the image; for example, the recording time may be controlled by a recording device such as a thermal printer (for example, Video Printer VY-100 manufactured by Hitachi Seisakusho). 5~100mJ/mrr? By applying a certain amount of thermal energy, the intended purpose can be fully achieved.

The method of the present invention will now be explained with reference to the accompanying drawings.

The thermal transfer sheet A shown in the first figure is transferred to a projector 6 as shown in the second figure.
When thermal transfer is carried out by attaching a printer and a light receiving sensor 7 on one side, the detection light 8 emitted from the projector 6 as the thermal transfer sheet A travels is reflected at the receiving layer 4, and the reflected light 9 is The light is received by the light receiving sensor 7. Regions other than the receiving layer, i.e., the dye layer 2 or the protective layer 4
is substantially translucent, so the detection light 8 is not detected by the light receiving sensor 7. The dye layers are formed in a predetermined order such as yellow, magenta, and cyan, so when the light-receiving sensor detects the detected light, the printer confirms the existence of the dye-receiving layer and continues to form yellow, magenta, and cyan ( and a protective layer) can be sequentially printed, and then the receptive layer is detected again and the above steps are repeated.

FIG. 3 shows another preferred embodiment of the present invention, in which a light emitter 6 and a light receiving sensor 7 are provided with a thermal transfer sheet A sandwiched therebetween. In this case, the device operates in the same manner as in FIG. 2 and produces the same effects, except that the receptor layer is detected when the light-receiving sensor does not detect detection light.

The apparatus of the present invention is similar to a conventionally known printer except that the loaded thermal transfer sheet has the above-mentioned configuration. Any thermal transfer device may be used as long as it has a detecting means including a light emitter and a light receiver.

(Example) Next, the present invention will be described in more detail with reference to Examples. In the text, unless otherwise specified, parts or percentages are based on weight.

Example 1 A polyethylene terephthalate film with a width of 30 cm and an interval of 1 was placed on the release-treated surface of a 4.5 μm thick polyethylene terephthalate film (manufactured by Toshi@), on which a heat-resistant slipping layer was formed on the back surface and a predetermined surface had been subjected to a release treatment.
A receiving layer, an intermediate layer, and an adhesive layer were stacked to form a 20 cm layer.

The receptive layer was formed by applying a receptive layer coating solution with the following composition using a bar coater at a dry rate of 3.0 g/rrr, temporarily drying it with a dryer, and then drying it in an oven at 100°C for 30 minutes. The intermediate layer was formed by applying and drying a urethane resin emulsion (Hytran AP-70, manufactured by Dainippon Ink & Chemicals) at a solid content of 3.0 g/d, and the adhesive layer was formed using the following adhesive solution. It was applied and dried in the same manner at a drying rate of 3.0g/1rd.

! Gosara Rie Liquid Plate Vinyl chloride/vinyl acetate copolymer resin (VYHD, manufactured by Union Carbide) 100 parts White pigment (
Titanium dioxide, manufactured by Tochem Brodac, TCA888
) 10 parts epoxy-modified silicone (F-393, manufactured by Shin-Etsu Chemical ■) 3 parts amino-modified silicone (X-22-343, manufactured by Shin-Etsu Chemical ■)
3 parts methyl ethyl ketone/toluene (weight ratio 1/1) 500 parts 1 ゛ ゛ ゛ ゛ ゛ ゛ ゛ ゛
D-37P295, manufactured by Toyo Morton ■) 100 parts water
Next, prepare 100 parts of an ink for the dye layer having the following composition, and apply it to each side of the base film on which the receiving layer is not formed using gravure caulk so that the dry coating amount is 1.0 g/rrr to a width of 30 cm. and dried to form a dye layer.

Tosha Okisatoenoma plate: Disperse dye (Kaya Set Blue 14, manufactured by Nippon Kakami)
4.0 parts Ethyl hydroxycellulose (manufactured by Vercules) 5.0 parts Methyl ethyl ketone/toluene (weight ratio 1/1) 80.
0 parts dioxane 10.0 parts Similarly, a yellow thermal transfer sheet was coated with yellow disperse dye (
Macrolex Yellow 6G, manufactured by Bayer, C, 1, Disperse Yellow 201
) and a magenta thermal transfer sheet with a magenta disperse dye (C,I).

Disperse Red60).

Subsequently, the following coating liquid was applied to a width of 30 cm at a solid content of 3.0/rrr and dried to form a transferable protective layer, thereby obtaining a thermal transfer sheet used in the present invention.

``1'' Recoko ℃ cosmetic acrylic resin (BR-83, manufactured by Mitsubishi Rayon■)
20 parts polyethylene wax 1 part methyl ethyl ketone/toluene (weight ratio 1/1) 80 parts The receiving layer surface of the above thermal transfer sheet and plain paper are superimposed,
In a thermal transfer device equipped with a detection means consisting of a light emitter and a light receiving sensor, output IW/
The receptor layer was transferred over the entire surface under the conditions of dots, pulse width 0.3 to 0, 45 m5ec, and dot density 3 dots/mm, and then yellow color obtained by color separation of the original was transferred onto the surface of the receptor layer. A signal was printed, and a yellow dye layer was overlaid to form a yellow image. Further, a magenta dye was similarly transferred to the image area obtained above using a magenta signal, a cyan dye was further transferred using a similar cyan signal, and a protective layer was further transferred to form a high-quality full-color image.

(Effects) According to the present invention as described above, by making the dye receiving layer white and opaque, the receiving layer can also be used as a detection mark.
There is no need to specially form a detection mark.

[Brief explanation of the drawing]

1 to 3 are diagrams schematically showing the method of the present invention, and FIGS. 4 and 5 are diagrams showing a conventional example. 1; Base film 2; Dye layer 3; Dye-receiving layer 4; Transferable protective layer 5; Detection mark 6; Emitter 7; Figure 4 Figure 5

Claims (4)

[Claims] (1) In a thermal transfer method in which an image-receiving sheet and a thermal transfer sheet are overlapped in a thermal transfer device, and heat is applied from the back side of the thermal transfer sheet to transfer the dye to the image-receiving sheet, the thermal transfer sheet is placed on one side of a long base film. A dye layer of one or more colors and one or more removable white dye-receiving layers are provided in a plane-sequential manner, and the detection light from the light projector provided in the thermal transfer device is transmitted to the white receiver. A thermal transfer method characterized by causing a thermal transfer device to detect a receptor layer by reflecting or blocking the layer. (2) The thermal transfer method according to claim 1, wherein the receptor layer includes an adhesive layer, and at least one of these layers is white. (3) The thermal transfer method according to claim 1, wherein the receptor layer includes an intermediate layer and an adhesive layer, and at least one of these layers is white. (4) In a thermal transfer device having an image receiving sheet, a conveying means thereof, a thermal transfer sheet, a conveying means thereof, a means for applying heat, and a detecting means consisting of a light emitter and a light receiver, the thermal transfer sheet is attached to one side of the elongated base film. A dye layer of one or more colors and one or more removable white dye-receiving layers are sequentially provided on the surface, and the detection light from the projector provided in the thermal transfer device is used to detect the white color. A thermal transfer device characterized in that the thermal transfer device is configured to detect a receiving layer by reflecting or blocking the receiving layer.