JP2000272258A - Thermal transfer sheet and integrated thermal transfer sheet - Google Patents

Abstract

(57) [Summary] [PROBLEMS] A composite heat transfer sheet without using expensive silver halide photographic film or optical equipment, useful for making a character negative film from a word processor, an underprint for plate making, a blank character, etc. Provide a sheet material that can easily create a pattern. SOLUTION: On one surface of a substrate 1, at least a vapor deposition anchor layer 2, a metal vapor deposition layer 3, and an adhesive layer 4 from the substrate 1 side.
Are formed on the thermal transfer sheet A in this order.
When the heat transfer sheet A was transferred to the image receiving sheet 7 having a light transmission density of 0.5 or less for a light beam of 400 nm,
The light transmission density of the transferred portion of the image receiving sheet is 2.0 or more. That is, the thermal head T
The vapor deposition anchor layer 2, the metal vapor deposition layer 3, and the adhesive layer 4 of the portion heated and applied by the above are transferred to the image receiving sheet 7 in a line drawing shape,
Then, the portion to which the heating is not applied is separated between the temporary adhesive layer 8 and the image receiving sheet 7 to form an image B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer sheet capable of recording characters and images by a thermal transfer method using a heating means such as a thermal head, and a heat transfer sheet and an image receiving sheet which can be peeled off via an adhesive layer. More particularly, the present invention relates to a sheet material useful for producing a mask film or a negative film used for plate making for printing or the like.

[0002]

2. Description of the Related Art Heretofore, various types of mask films, negative films, peelable films and the like have been used in large quantities for preparing plates used for printing and the like. When a light-shielding property is required, these films used as plate making materials have been used by optically forming an image with a photographic film of a silver salt or with a photochromic film.

[0003]

The silver halide film used in the prior art is excellent in quality such as sharpness of image formation, but is expensive and has a problem in cost. When high resolution is not required and small-lot printing is performed using a silver halide film, the material ratio increases in the case of small-lot printing, and the cost becomes relatively high. Then, there was a problem that it was difficult to handle. Further, in order to form a negative image having a high density on a transparent film from a simple printer such as a word processor, there are two types of films: a sheet having a peelable ink layer and a release film for applying and peeling the ink layer. And sheets are supplied from two units. But,
This method has a problem that the types of printers having two units of paper feeding units are limited.

[0004] Therefore, the present invention can solve the above-mentioned drawbacks, and can use an expensive silver halide photographic film or a composite heat transfer sheet, without using optical equipment, from a word processor or the like to a character negative film or a plate for plate making. It is an object of the present invention to provide a sheet material capable of easily forming a pattern useful for forming a blank character (a character extracted white in the ground color) or the like. Incidentally, the sheet material is a thermal transfer sheet and the thermal transfer sheet and the image receiving sheet via a temporary adhesive layer,
This is an integrated thermal transfer sheet that is temporarily adhered so that it can be peeled off.

[0005]

In order to achieve the above-mentioned object, the present invention provides a method for forming at least a deposition anchor layer, a metal deposition layer and an adhesive layer on one surface of a substrate from the substrate side in this order. In the heat transfer sheet obtained, a wavelength of 300 to 400
When the thermal transfer sheet is transferred to an image receiving sheet having a light transmission density of 0.5 or less for a light beam of nm, the light transmission density of the transferred portion of the image receiving sheet becomes 2.0 or more. Further, it is preferable that at least one of the deposition anchor layer and / or the adhesive layer of the thermal transfer sheet is added with a coloring material composed of a dye and / or a pigment. Further, it is preferable that at least an ultraviolet absorber of the vapor deposition anchor layer and / or the adhesive layer of the thermal transfer sheet is added. Further, the present invention is an integrated thermal transfer sheet in which any one of the above-mentioned thermal transfer sheets and an image receiving sheet are temporarily adhered releasably via a temporary adhesive layer. Incidentally, the light transmission density is defined as follows in the present invention.
It is an amount indicating the degree to which a given substance layer (ink-removed portion and ink-remaining portion of the image-receiving sheet after printing) absorbs light, and has the same meaning as the absorbance. The higher the numerical value, the greater the amount of light absorption (the lower the light transmission). As = log ₁₀ (I _o / I) I _o I _o is the incident light intensity, and I is the transmitted light intensity after passing through the material layer (analyte).

[0006]

The thermal transfer sheet according to the present invention is provided on one side of the substrate,
At least a deposition anchor layer, a metal deposition layer, and an adhesive layer are formed in this order from the base material side, and a wavelength of 300 to 400 nm.
When the thermal transfer sheet is transferred to an image receiving sheet having a light transmission density of 0.5 or less for the light rays, the light transmission density of the transferred portion of the image receiving sheet becomes 2.0 or more. Referring to FIG. 5, the portions where the thermal transfer sheet A side is heated and applied by the thermal head T or the like are the deposition anchor layer 2 and the metal deposition layer 3.
Then, the adhesive layer 4 is transferred to the image receiving sheet 7 in the form of a line drawing, and the portion not heated is separated between the temporary adhesive layer 8 and the image receiving sheet 7 to form an image B. That is, the light transmission density of the portion (the vapor deposition anchor layer 2, the metal vapor deposition layer 3, and the adhesive layer 4) transferred to the image receiving sheet 7 becomes 2 or more, the ink layer remains on the image receiving sheet surface, and the light source is sufficiently shut off. It can form a clear, positive or negative image comparable to silver halide photographic films and other photoresists. When the light transmission density is less than 2.0, when used for a mask film or the like, the light source is not sufficiently shielded, and a sharp latent image is not formed.

[0007]

Next, a preferred embodiment will be described with reference to the drawings. FIG. 1 is a sectional view showing one embodiment of the thermal transfer sheet of the present invention. As shown in FIG. 1, the thermal transfer sheet of the present invention is provided with a base material 1 and a release layer 6, a deposition anchor layer 2, a metal deposition layer 3, and an adhesive layer 4 on one surface of the base material 1 in this order. A back layer 5 can be provided on the other surface of the substrate 1. FIG. 2 shows another embodiment of the thermal transfer sheet of the present invention, in which one surface of a substrate 1 is provided with a vapor deposition anchor layer 2, a metal vapor deposition layer 3 and an adhesive layer 4.
Are provided in this order, and the deposition anchor layer 2 also functions as a release layer.

(Substrate) As the substrate 1 used in the thermal transfer sheet of the present invention, the same substrate as that used in the conventional thermal transfer sheet can be used as it is, and other substrates can also be used. And is not particularly limited. Specific examples of the preferred substrate 1 include, for example, polyester, polypropylene, cellophane, polycarbonate, cellulose acetate, polyethylene, polyvinyl chloride,
Polystyrene, nylon, polyimide, polyvinylidene chloride, polyvinyl alcohol, fluororesin, chlorinated rubber,
There are papers such as a plastic film such as an ionomer and the like, condenser paper, paraffin paper and the like, and a composite of any of these may be used. The thickness of the substrate 1 can be appropriately changed depending on the material so that the strength and the thermal conductivity thereof become appropriate. However, the thickness is preferably about 2 to 12 μm in view of the printing (recording) sensitivity. That is, if the thickness is less than 2 μm, the strength as a substrate film tends to be insufficient, and if the thickness exceeds 12 μm, heat during printing (recording) becomes difficult to be transmitted to the outermost adhesive layer.

(Back Layer) It is also possible to provide a back layer 5 on one surface of the substrate to prevent sticking of the thermal head and improve the slipperiness. The back layer 5 is formed by suitably using a binder resin to which a slip agent, a surfactant, inorganic particles, organic particles, a pigment and the like are added. The binder resin used for the back layer 5 includes, for example, cellulose resins such as ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, methyl cellulose, cellulose acetate, cellulose acetate butyrate, and nitrated cotton, polyvinyl alcohol, polyvinyl acetate, polyvinyl butyral, and polyvinyl. Acetal, polyvinylpyrrolidone, acrylic resin, polyacrylamide, acrylonitrile-vinyl resin such as styrene copolymer, polyester resin, polyurethane resin,
Silicone-modified or fluorine-modified urethane resins, melamine resins, urea resins, and the like can be given. Among them, it is preferable to use a cross-linking resin using one having several reactive groups, for example, a hydroxyl group, and using a polyisocyanate as a cross-linking agent in combination. The thickness of the back layer is usually about 0.01 to 10 μm in a dry state.

(Release Layer) A release layer 6 can be provided between the substrate and the deposition anchor layer, if necessary. The release layer 6 is a layer that forms the outermost surface of a recorded material by transferring all or a part of the thermal transfer recording element from the thermal transfer recording element in the thickness direction or by cohesive failure during transfer recording. In the case of partial transfer or full transfer, it is preferable that the cohesive force at the time of recording be low so that the foil during printing is good. Alternatively, the layer may not transfer at all. In short, the release layer is a layer that allows the thermal transfer recording element to be peeled off at this layer or at a surface adjacent to the layer, thereby enabling separation of the base material and the metal deposition layer.

Examples of the release layer 6 include carnauba wax, paraffin wax, microcrystalline wax, ester wax, Fischer-Tropsch wax, various low molecular weight polyethylenes, wood wax, beeswax, whale wax, ibota wax, wool wax, shellac wax, Various waxes such as candelilla wax, petrolactam, partially modified wax, fatty acid ester and fatty acid amide can be used.

As the release layer 6, a resin other than the above wax can be used as long as the releasability from the base material or the like is appropriate, and the resin alone or a mixture of the above wax and the resin may be used. Examples of such a resin include rubber resins such as polyisoprene rubber, styrene butadiene rubber, butadiene acrylonitrile rubber, acrylate resin, polyvinyl ether resin, polyvinyl acetate resin, and vinyl chloride-vinyl acetate copolymer. Body resin, polystyrene resin, polyester resin, polyamide resin, polyimide resin, polychlorinated olefin resin,
Polycarbonate, polyvinyl butyral-based resin and the like can be mentioned. The thickness of the release layer 6 is generally 0.1 to
It is in the range of 10 g / m ² . When it is less than 0.1 g / m ^2, it does not function as a peeling layer, and when it exceeds 10 g / m ² , foil breakage at the time of printing is reduced, and especially halftone recording cannot be performed well. In some cases, it may become unusable due to a decrease.

(Evaporation anchor layer) The evaporation anchor layer 2 comprises:
The purpose is to provide a base for metal deposition and to protect a substrate and the like from heat during the deposition. After the transfer printing, it is transferred to the transfer receiving body together with the metal vapor deposition layer, and is located above the metal vapor deposition layer and is in close contact with the metal vapor deposition layer to become one component of the recorded matter. Function as a protective layer to improve mechanical and chemical strength such as abrasion and corrosion,
The material is not particularly limited as long as the material has transparency enough to allow the metallic gloss of the metal deposition layer to be seen through. Such materials include, for example, alkyd resins, phenolic resins, polyimides, epoxy resins, urethane resins, thermosetting resins such as unsaturated polyester resins, polyethylene,
Olefinic resins such as polypropylene, acrylic resins such as polymethyl methacrylate and polyacrylamide,
Styrene resins such as polystyrene, polyvinyl resins such as polyvinyl chloride and polyvinyl acetate, polyoxymethylene,
Examples include thermoplastic resins such as polyether resins such as polyphenylene oxide, polyvinyl butyral resins, nitrocellulose resins, and ethyl cellulose resins.

The thickness of the deposition anchor layer is usually set in the range of 0.1 to 20 g / m ^{2 in} terms of the amount of coating, in order to function as a metal deposition base layer and a protective layer. Further, for the main purpose of coloring the metal deposition layer with aluminum or the like, for example, known dyes and / or pigments such as cyan, magenta, yellow, black and other color materials can be appropriately mixed. If the thickness is less than 0.1 g / m ^2, it does not function as a vapor deposition anchor layer, and if it exceeds 20 g / m ² , the foil breakage at the time of printing becomes poor, and halftone recording becomes difficult. Further, an ultraviolet absorber is added to the vapor deposition anchor layer, and after the thermal transfer sheet is heated, the light transmission density with respect to light having a wavelength of 300 to 400 nm of the portion transferred to the image receiving sheet is further increased to 2.0 or more. Is preferably performed. As the ultraviolet absorber, inorganic and organic ultraviolet absorbers can be used, but from the viewpoint of excellent weather resistance, inorganic ultraviolet absorbers are preferably used. Specific examples of the inorganic ultraviolet absorber include titanium oxide and zinc oxide.
Examples of the organic ultraviolet absorber include those based on benzotriazole, benzophenone, and benzoic acid ester.

Further, the peeling layer 5 and the vapor deposition anchor layer 2 can be used also. In this case, since the waxes have insufficient heat resistance at the time of vapor deposition, the above-described resin is used in view of heat resistance, mold releasability from the substrate side, adhesion to the metal vapor-deposited layer, foil breakability during printing, and the like. Among them, those having a relatively low molecular weight and low cohesion can be used.

(Metal Deposition Layer) The metal deposition layer 3 is formed by metallizing a metal such as aluminum, zinc, tin, chromium, gold, silver, or an alloy such as brass under vacuum such as vacuum deposition and sputtering. It is a metal thin film layer obtained. The thickness of the metal deposition layer is usually 100 to 1000 °,
Preferably, the range of 200 to 600 ° is sufficient for the light transmission density of the transferred portion of the image receiving sheet to be 2.0 or more. If it is too thin, partial unevenness may occur, causing pinholes and the like. On the other hand, if the thickness is too large, the foil breakage at the time of printing becomes worse, image reproducibility is not good, and it is uneconomical.

(Adhesive Layer) As the adhesive layer 4, wax or a thermoplastic resin alone or a mixture thereof is used.
Examples of the wax include carnauba wax, paraffin wax, microcrystalline wax, ester wax, Fuscher-Tropsch wax, various low molecular weight polyethylenes, wood wax, beeswax, whale wax, ibota wax, wool wax, shellac wax, candelilla wax, petrolactam. Various known waxes such as partially modified waxes, fatty acid esters and fatty acid amides can be used. Further, as the thermoplastic resin, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, and the like, an ethylene-based copolymer of ethylene and other polymerizable monomers Copolymers can preferably be used.

When the ethylene copolymer is used in combination with a wax, the ethylene copolymer has good compatibility with the wax, and after printing an image, the entire adhesive layer has a moderately high cohesive force, thereby realizing high fixability. Examples of the copolymerized monomer with ethylene include acrylic acid esters and methacrylic acid esters in addition to the above-mentioned vinyl acetate, acrylic acid and methacrylic acid. For example, ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl methacrylate copolymer, ethylene-ethyl methacrylate copolymer, and the like. The copolymerization monomer with ethylene is not limited to one kind, but may be a multi-component copolymer obtained by copolymerizing a plurality of kinds. Further, a plurality of these copolymers may be used in combination. In addition, a plurality of copolymers having different copolymerization ratios and molecular weights or different copolymers may be used as a mixture of copolymers composed of the same copolymerization monomer. In addition, the copolymerization ratio of the ethylene-based copolymer is preferably such that the ethylene component is in the range of 50 to 95 with respect to the total weight of the copolymer being 100, from the viewpoint of balance such as fixing property and blocking resistance.

The ethylene copolymer preferably has a weight average molecular weight (Mw) in the range of 1,000 to 100,000. When a plurality of copolymers are used, the molecular weight of each copolymer is preferably within the above range. If the weight average molecular weight is less than 1,000, the resin tends to flow even at room temperature, causing a tacky feeling in the adhesive layer, resulting in reduced storage stability. Of the foil becomes worse, the resolution is reduced, and a problem occurs in the recording of halftone tone.

As the thermoplastic resin used for the adhesive layer, in addition to the above-mentioned ethylene copolymer, other conventionally known resins used as an adhesive layer for other thermal transfer materials may be used in combination. For example, polyethylene resin, polypropylene resin, polyvinyl acetate, polyester resin, polyurethane resin, styrene resin, acrylic resin, polyamide resin, polyvinyl alcohol, polyvinyl acetate,
Petroleum resin, phenol resin, maleic acid resin, etc., or synthetic rubber such as polyisoprene rubber, styrene-butadiene rubber, butadiene-acrylonitrile rubber, and elastomers such as natural rubber. These resins may be used in combination, if necessary, depending on the type of surface material of the transfer object.

The thermoplastic resin, particularly an ethylene copolymer, and the wax are contained in the adhesive layer in the form of fine particles, whereby the cohesive force at the time of thermal transfer can be suppressed, and the foil at the time of printing can be suppressed. The sharpness is generally improved, and high-resolution and high-sensitivity recording can be performed. In order for the fine particles to be contained in the adhesive layer, a dispersion or emulsion of these fine particles may be applied as an adhesive layer and dried at a temperature lower than the melting point or softening point of the fine particles. In addition, the fine particle state does not mean only a spherical shape, but a state in which substantially spherical independent fine particles in an emulsion are loosely bonded to an original fine particle unit by an external force while deforming the shape by moderate heat. Means the fine particles in the above. When the wax and the thermoplastic resin are contained as fine particles, the average particle diameter of each of the wax fine particles and the thermoplastic resin fine particles is 10%.
It is preferable that the thickness be not more than μm. If the average particle size exceeds 10 μm, not only the printing sensitivity is lowered, but also the foil holding of the adhesive layer is significantly reduced.

The adhesive layer may be appropriately mixed with known colorants of cyan, magenta, yellow, black and other colors using dyes and / or pigments. Further, an ultraviolet absorber is added to the adhesive layer, and after heating the thermal transfer sheet, the wavelength of the portion to be transferred to the image receiving sheet is 300 to 400.
It is preferable to further increase the light transmission density for a light beam of nm to 2.0 or more. In addition, as the specific examples of the ultraviolet absorber, those described for the deposition anchor layer can be used similarly. The thickness of the adhesive layer depends on the surface shape of the material to be transferred, but the thinner it is, the better the printing sensitivity and the fixing of the printed image, as long as the glossiness of the metal deposition layer and the cutting ability of the foil are not impaired. It is preferable in terms of performance and resolution. For example, the coating amount is in the range of 0.5 to 5 g / m ² , preferably 1 to 3 g / m ² . If it is less than 0.5 g / m ² , sufficient adhesive strength cannot be obtained, resulting in poor sensitivity. If it exceeds 5 g / m ² , excessive energy is required to melt the adhesive layer, and foil breakage is undesirably reduced. In addition, in order to form a release layer, a vapor deposition anchor layer, an adhesive layer or a back layer, as a coating liquid in which the constituent materials of the layer are dissolved or dispersed in a solvent such as an organic solvent, a conventionally known gravure coat, gravure reverse coat, It can be formed by a roll coat, a knife coat, and many other known coating means. In the case of a layer mainly composed of wax, coating means such as hot melt coating and hot lacquer coating can also be used.

Next, an image receiving sheet for thermal transfer integrated with the thermal transfer sheet will be described. FIG. 3 is a sectional view showing one embodiment of the integrated thermal transfer sheet of the present invention,
A base material 1, a vapor deposition anchor layer 2, a metal deposition layer 3, and an adhesive layer 4 are provided in this order on one surface of the base material 1, and a thermal transfer image receiving sheet 7 and a base material 1 / a vapor deposition anchor layer 2 / metal deposition The heat transfer sheet A composed of the layer 3 and the adhesive layer 4 is temporarily adhered to the adhesive layer 4 so as to be peelable. In this case, the adhesive layer 4 of the thermal transfer sheet also has the function of the temporary adhesive layer. FIG. 4 is a cross-sectional view showing another embodiment of the integrated thermal transfer sheet of the present invention, in which a release layer 6, a deposition anchor layer 2, a metal deposition layer 3, and an adhesive layer 4 Are provided in this order, and a thermal transfer sheet A provided with a back layer 5 and an image receiving sheet 7 are temporarily adhered to the other surface of the substrate 1 via a temporary adhesive layer 8 so as to be peelable. .

(Image-Receiving Sheet) The substrate film used for the image-receiving sheet 7 is preferably transparent to visible light and ultraviolet light, but when used as a negative film or a mask film, Transparency to visible light is not essential, and 300
It may be colored under visible light as long as it is substantially transmissive to ultraviolet light of up to 400 nm. Also,
In the case where an image is formed as a blank character by applying heating, the image is not necessarily required to be transparent, and a colored film containing opaque white may be used.

The base film used for the image receiving sheet 7 is generally an ordinary plastic sheet, for example, polyester, polypropylene, polycarbonate, or the like.
In addition to stretched films such as cellulose acetate, vinyl chloride, saponified ethylene / vinyl acetate copolymer and the like, unstretched films, papers containing synthetic paper, and laminated films of these are also included. In addition, the base film is required to have rigidity because it is handled in a single step in a subsequent step, and its thickness is determined by a material and a manufacturing method, but is preferably 50 to 200 μm.

(Temporary Adhesive Layer) The temporary adhesive layer 8 may be made of any conventionally known adhesive, but is preferably a tacky resin and wax having a low glass transition temperature, or a particle shape at room temperature. It is preferable to use a mixture of thermoplastic fine particles and a wax which is maintained but heated to form a film. The adhesive force (g) of such a temporary adhesive layer 8 is 25 mm (width) ×
A sample of 55 mm (length) was cut out, and measured with a surface friction meter (HEIDEN-17, manufactured by Shinto Kagaku) for 1,8.
When measured at a pulling speed of 00 mm / min, 30
Those having a range of 0 to 2,000 g are preferred. If the adhesive force is less than the above range, the adhesive force between the thermal transfer sheet and the image receiving sheet for thermal transfer is too low, so that the thermal transfer sheet and the thermal transfer sheet are easily peeled off, and the thermal transfer sheet is apt to wrinkle. When the adhesive force exceeds the above range, the adhesive force is sufficient, but the metal vapor deposited layer is easily transferred to the thermal transfer image receiving sheet even in the non-printed portion, and the background of the thermal transfer image receiving sheet is stained. Inconvenience that it is easy to perform occurs.

The above adhesive resin used for the temporary adhesive layer 8 has a glass transition temperature of -90 ° C. to -5 ° C.
Those in the range of 0 ° C. are preferred. Specifically, there are a rubber-based adhesive resin, an acrylic-based adhesive resin, a silicone-based adhesive resin, and the like. Examples of the form include a solvent solution type, an aqueous solution type, a hot melt type, an aqueous or oily emulsion type, and the like. Any of them can be used. further,
At room temperature, the particle shape is maintained, but examples of thermoplastic fine particles that form a film under heating include polyethylene resin, ionomer resin, and ethylene-vinyl acetate copolymer resin. Some are preferred. When such an adhesive resin is used alone,
Although excellent adhesiveness is obtained, the peelability of the thermal transfer paper is insufficient and uneven.If unexpected force is applied before thermal transfer, such as during manufacturing, storage, or transportation, the thermal transfer sheet The metal deposition layer is transferred to the thermal transfer image receiving sheet side,
There is a problem that a background stain is generated. In addition, at the time of thermal transfer, the metal-deposited layer has poor foil-cutting properties. For example, the metal-deposited layer transfers to the periphery of a region to which heat is applied by a thermal head, and the resolution of a transferred image is poor.

These problems can be solved by adding the wax emulsion used in the formation of the adhesive layer to the above-mentioned emulsion tacky resin, whereby the adhesiveness can be adjusted to a preferable range. Is eliminated, and the resolution of the transferred image is improved. The weight ratio of the above-mentioned adhesive resin and wax is preferably 1: 0.5 to 6. Outside of this range, various problems as described above are likely to occur, which is not preferable. The temporary adhesive layer 8 composed of the above components may be provided on the surface on the side of the image receiving sheet for thermal transfer, but the temporary adhesive layer 8 may be provided on the side of the thermal transfer sheet in order to maintain adhesiveness on printed matter. preferable. in this case,
Since the tacky resin of the temporary adhesive layer 8 is used as an aqueous emulsion, the metal deposited layer is not damaged. Also,
The method for applying and drying the emulsion is not particularly limited, and various known methods can be selected.

The temporary adhesive layer 8 has a thickness of 0.1
10 to 10 μm (solids coating amount, 0.05 to 5 g /
m ² ). Adhesion between the thermal transfer sheet and the thermal transfer image-receiving sheet is performed by continuously adhering the thermal transfer image-receiving sheet using the adhesiveness imparted to the adhesive layer or the temporary adhesive layer 8 of the thermal transfer sheet, and winding the roll into a roll. Done by taking. At the time of winding, the image receiving sheet for thermal transfer may be on the outside, the thermal transfer sheet may be on the outside, or these may be cut into sheets.
The temporary adhesive layer 8 can also have the function of the adhesive layer 4 described above, in which case, the adhesive layer of the thermal transfer sheet
It is possible to omit the temporary adhesive layer. (See Fig. 3)

The integrated thermal transfer sheet of the present invention configured as described above is most suitable for a thermal printer using a thermal head, but can also be used as a transfer foil in a hot stamping method. In addition, in order to be superior in resolution,
It is also suitable for use in printing images such as characters and designs as an aggregate of minute patterns, and can impart metallic luster to these images. Therefore, as a density gradation expression method, an intermediate density can be reproduced by expressing the density gradation by the size of the transfer portion according to the size of the halftone dot, that is, by using the area gradation. In addition, as a method of the area gradation, a screen pattern or the like known in the printing field using a grain, a brick pattern, or the like can be used in addition to a halftone dot. In particular, when a wax or a thermoplastic resin component used for the adhesive layer is contained as fine particles, it can be applied to area gradation recording requiring high resolution.

The thermal transfer sheet or the integrated thermal transfer sheet of the present invention is set on a printer or a plotter. For example, referring to FIG. Heat may be applied to the image with a pen or the like, and the vapor-deposited anchor layer 2, the metal-deposited layer 3, and the adhesive layer 4 at the heated and applied portions are transferred to the image-receiving sheet 7 in the form of a line drawing. The part which is not formed is separated between the temporary adhesive layer 8 and the image receiving sheet 7, and a desired image B is formed on the image receiving sheet. The thus formed image is exposed to visible light, preferably 300 to 400 nm ultraviolet light, on a silver halide film, a photosensitive paper or the like as a negative film, a mask film or the like, so that the silver halide film is positively exposed. An image can be formed. Also, by forming a photoresist layer on an arbitrary substrate and exposing similarly, a negative pattern or a positive pattern on the substrate can be easily provided according to the type of the photoresist. Furthermore, when the image receiving sheet is formed of an opaque film,
An image of a blank character can be configured.

[0032]

The present invention will be described more specifically with reference to examples and comparative examples. In the text, "part" or "%" means
Unless otherwise specified, it is based on weight. (Example 1) <Production of thermal transfer sheet> One surface of a base material of a 4.5 μm-thick polyethylene terephthalate film (Lumirror manufactured by Toray Industries, Inc.) having a back surface layer provided on the back surface (a back surface layer is provided) The coating solution for the release anchor layer having the following composition was coated on the uncoated surface) with a gravure coater at an application amount of 0.7 g / m ² (solid content) and dried to form a release anchor layer. Next, aluminum was formed as a metal deposition layer on the release anchor layer by sputtering at a thickness of 300 °. Further, on the metal deposition layer, 2.0 g of a coating solution for an adhesive layer having the following composition was applied using a roll coater.
/ M ² (solid content) and dried to form an adhesive layer. Thus, the thermal transfer sheet of Example 1 was obtained.

Coating solution for release anchor layer Polyamide imide resin 25 parts Carbon black 8 parts Toluene 37 parts Denatured ethanol 37 parts

Coating solution for adhesive layer Ethylene-acrylic acid copolymer 3 parts Carnauba wax 8 parts Water 7 parts Isopropyl alcohol 15 parts

Next, the above-mentioned thermal transfer sheet was releasably attached to an image receiving sheet (polyethylene terephthalate film having a thickness of 75 μm) to which the following coating solution for a temporary adhesive layer was applied. An integrated thermal transfer sheet having a deposition layer was obtained. The bonding conditions are nip temperature 5
The temperature was set to 0 ° C. and the nip pressure was set to 5 kg / cm ² . Acrylic resin for temporary adhesive layer 4 parts Carnauba wax 2 parts Water 3 parts Isopropyl alcohol 6 parts

Example 2 <Preparation of Thermal Transfer Sheet> One surface (back surface layer) of a 4.5 μm thick polyethylene terephthalate film (Lumirror manufactured by Toray Industries, Inc.) having a back surface layer on the back surface Is coated with a coating solution for a release anchor layer having the following composition at a coating amount of 0.7 g / m ² (solid content) using a gravure coater and dried to form a release anchor layer. did. Next, aluminum was formed as a metal deposition layer on the release anchor layer by sputtering at a thickness of 300 °. Further, on the metal deposition layer, 2.0 g of a coating solution for an adhesive layer having the following composition was applied using a roll coater.
/ M ² (solid content) and dried to form an adhesive layer. Thus, a thermal transfer sheet of Example 2 was obtained.

Coating solution for release anchor layer Polyamide-imide resin 25 parts Toluene 37 parts Denatured ethanol 37 parts

Coating liquid for adhesive layer 3 parts ethylene-acrylic acid copolymer 8 parts carnauba wax 7 parts water 15 parts isopropyl alcohol

Next, the thermal transfer sheet and the image receiving sheet (polyethylene terephthalate film having a thickness of 75 μm) were releasably bonded in the same manner as in Example 1, and an integrated type having a metal deposition layer of Example 2 was obtained. A thermal transfer sheet was obtained.

Example 3 <Preparation of Thermal Transfer Sheet> One surface (back surface layer) of a 4.5 μm thick polyethylene terephthalate film (Lumirror manufactured by Toray Industries, Inc.) having a back surface layer on the back surface Is coated with a coating solution for a release anchor layer having the following composition at a coating amount of 0.7 g / m ² (solid content) using a gravure coater and dried to form a release anchor layer. did. Next, aluminum was formed as a metal deposition layer on the release anchor layer by sputtering at a thickness of 300 °. Further, on the metal deposition layer, 2.0 g of a coating solution for an adhesive layer having the following composition was applied using a roll coater.
/ M ² (solid content) and dried to form an adhesive layer, thereby obtaining a thermal transfer sheet of Example 3.

Coating solution for release anchor layer Polyamide imide resin 25 parts Carbon black 8 parts Toluene 37 parts Denatured ethanol 37 parts

Coating solution for adhesive layer Ethylene-acrylic acid copolymer 3 parts Carnauba wax 8 parts Carbon black 5 parts Water 7 parts Isopropyl alcohol 15 parts

Next, the thermal transfer sheet and the image receiving sheet (polyethylene terephthalate film having a thickness of 75 μm) were releasably adhered in the same manner as in Example 1, and an integrated type having a metal deposition layer of Example 3 was obtained. A thermal transfer sheet was obtained.

(Comparative Example 1) <Preparation of Thermal Transfer Sheet> One surface (back surface layer) of a 4.5 μm thick polyethylene terephthalate film (Lumirror manufactured by Toray Industries Co., Ltd.) having a back surface layer on the back surface Was applied with a gravure coater at a coating amount of 0.7 g / m ² (solid content) and dried to form a release layer. next,
On the release layer, a coating solution for an ink layer in which carbon black having the following composition was dispersed was applied at 2.0 g / roll by a roll coater.
m ² coating of the coating amount (solid content) and dried to form an ink layer, to obtain a thermal transfer sheet of Comparative Example 1.

Coating liquid for release layer 25 parts paraffin wax 30 parts water 60 parts isopropyl alcohol

Coating solution for ink layer Ethylene-vinyl acetate copolymer 10 parts Acrylonitrile butadiene rubber 10 parts Carnauba wax 40 parts Carbon black 30 parts Water 30 parts

Next, the above-mentioned thermal transfer sheet and an image receiving sheet (a polyethylene terephthalate film having a thickness of 75 μm) were releasably bonded in the same manner as in Example 1 to obtain an integrated thermal transfer sheet of Comparative Example 1. . Using the integrated thermal transfer sheets of the above Examples and Comparative Examples, setting on a large plotter, printing under an environment of 25 ° C. and 50% RH, and then peeling off the thermal transfer image receiving sheet,
Various desired negative images were formed on the thermal transfer image-receiving sheet, and their light transmission densities were measured with a spectrophotometer. The results shown in the following table were obtained.

[0048]

[Table 1]

[0049]

According to the present invention, as described above,
On one surface of the substrate, at least a vapor deposition anchor layer, a metal vapor deposition layer, and an adhesive layer are formed in this order from the substrate side, and the light transmission density with respect to light having a wavelength of 300 to 400 nm is 0.5.
When the thermal transfer sheet was transferred to the following image receiving sheet, the light transmission density of the transferred portion of the image receiving sheet was 2.0
Above. Thereby, without using an expensive silver halide photographic film or optical equipment, it is possible to create a character negative film, an underlay for plate making by a thermal transfer method, and has a sufficient light shielding property as a plate making material, We can use without trouble. Further, a pattern useful for creating a blank character or the like can be easily created.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one embodiment of a thermal transfer sheet of the present invention.

FIG. 2 is a cross-sectional view illustrating another embodiment of the thermal transfer sheet of the present invention.

FIG. 3 is a sectional view showing one embodiment of the integrated thermal transfer sheet of the present invention.

FIG. 4 is a sectional view showing another embodiment of the integrated thermal transfer sheet of the present invention.

FIG. 5 is a conceptual diagram of a cross section showing a state in which an image is formed on an image receiving sheet by applying heat from a thermal transfer sheet side with a thermal head and transferring the heated portion to a line drawing.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 base material 2 vapor deposition anchor layer 3 metal deposition layer 4 adhesive layer 5 back layer 6 release layer 7 image receiving sheet 8 temporary adhesive layer A thermal transfer sheet B image T thermal head

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Noritaka Ega, Inventor 1-1-1, Ichigaya-Kaga-cho, Shinjuku-ku, Tokyo F-term in Dai Nippon Printing Co., Ltd. (reference) 2H111 AA04 AA26 AB02 BA02 BA03 BA04 BA07 BA09 BA38 BA55 CA03

Claims (4)

[Claims] 1. A thermal transfer sheet in which at least a vapor deposition anchor layer, a metal vapor deposition layer and an adhesive layer are formed on one surface of a substrate from the substrate side in this order, a wavelength of 300 to 400
When the thermal transfer sheet is transferred to an image receiving sheet having a light transmission density of 0.5 or less for a light ray of nm, the light transmission density of the transferred portion of the image receiving sheet is 2.0 or more. Thermal transfer sheet. 2. The thermal transfer according to claim 1, wherein a color material comprising a dye and / or a pigment is added to at least one of the deposition anchor layer and / or the adhesive layer of the thermal transfer sheet. Sheet. 3. The heat transfer sheet according to claim 1, wherein at least an ultraviolet absorber of the deposition anchor layer and / or the adhesive layer of the thermal transfer sheet is added.
Thermal transfer sheet described in 1. 4. The thermal transfer sheet and the image receiving sheet according to claim 1 through a temporary adhesive layer,
An integrated thermal transfer sheet which is temporarily adhered so as to be peelable.