JP3908765B2 - Thermal transfer sheet - Google Patents

Description

  The present invention relates to a thermal transfer sheet in which a heat-resistant slipping layer is provided on one surface of a substrate, and an adhesive layer and a dye layer are sequentially formed on the other surface of the substrate. The present invention relates to a thermal transfer sheet that can prevent abnormal transfer such that the entire dye layer is transferred during printing on a transfer body.

  Conventionally, various thermal transfer recording methods are known. Among them, a thermal transfer sheet having a dye layer in which a dye for sublimation transfer is used as a recording material and this is supported on a base material such as a polyester film with a suitable binder. From the above, there are proposed methods for forming various full-color images by thermally transferring a sublimation dye onto a transfer material that can be dyed with a sublimation dye, for example, a thermal transfer image-receiving sheet having a dye-receiving layer formed on paper or a plastic film. Yes. In this case, as the heating means, the color dots having a large number of three or four colors adjusted by heating with the thermal head of the printer are transferred to the receiving layer of the thermal transfer image receiving sheet, and the multicolored color dots are transferred. To reproduce the full color of the document. The image formed in this way is very clear and excellent in transparency because the coloring material used is a dye, so the resulting image is excellent in the reproducibility and gradation of intermediate colors, It is possible to form a high-quality image similar to an image obtained by offset printing or gravure printing and comparable to a full-color photographic image.

  In such a thermal transfer recording system using sublimation transfer, as the printing speed of the thermal transfer printer is increased, there has been a problem that a sufficient print density cannot be obtained with the conventional thermal transfer sheet. Also, there has been a demand for higher density and clearer prints of thermal transfer images, and improved thermal transfer image-receiving sheets that accept images of sublimation dyes transferred from the thermal transfer sheet and the thermal transfer sheet. Many attempts have been made. For example, attempts have been made to improve transfer sensitivity in printing by reducing the thickness of the thermal transfer sheet, but wrinkles may occur due to heat, pressure, etc. during manufacture of the thermal transfer sheet or during thermal transfer recording. Causes the problem of cutting.

  In addition, the dye / resin (Dye / Binder) ratio in the dye layer of the thermal transfer sheet was increased to try to improve the print density and transfer sensitivity in the print. When the dye is transferred to the heat-resistant slipping layer of the ink and the transferred dye is rolled back, it is re-transferred to the dye layer of another color (kickback), and the contaminated layer is thermally transferred to the image receiving sheet. The hue may be different from that of the original color, or the so-called background stain may occur. In the thermal transfer printer, not on the thermal transfer sheet side, high energy is applied during thermal transfer during image formation. However, the dye layer and the receiving layer are fused, and so-called abnormal transfer is likely to occur. When a large amount of a release agent is added to the receiving layer to prevent the abnormal transfer, blurring of the image, background smearing, etc. occur.

  Further, as a prior art, Patent Document 1 discloses a thermal transfer in which a polyvinyl pyrrolidone as a main component and a hydrophilic barrier / undercoat layer using a mixture of polyvinyl alcohol as a component for improving dye transfer efficiency is provided between a dye layer and a support. A sheet is disclosed. This polyvinyl pyrrolidone is for preventing abnormal transfer and preventing adhesion at the time of printing.Polyvinyl alcohol has a function of improving transfer sensitivity, and that polyvinyl pyrrolidone improves transfer sensitivity. There is no description.

  In addition, the present applicant describes in Patent Document 2 that the use of a dye layer primer layer containing polyvinyl pyrrolidone has the effect of increasing the sensitivity in thermal transfer and abnormal transfer. Depending on the properties, the adhesion of the primer layer decreases, especially under high temperature and high humidity, and the dye layer is taken together with the receiving layer of the image receiving sheet during thermal transfer, or because the primer layer and the dye layer are mixed. There arises a problem that the receiving layer is taken together with the possible dye layer.

As described above, thermal transfer recording materials for thermal transfer sheets and thermal transfer image-receiving sheets that can be adjusted and used on the thermal transfer printer side in response to higher printing speeds of thermal transfer and higher density and quality requirements of thermal transfer images However, in this situation, a sufficient print density cannot be obtained, abnormal transfer occurs during thermal transfer, other problems occur, and a sufficiently high quality print cannot be obtained.
Japanese Examined Patent Publication No. 7-102746 Japanese Patent Application No. 14-181812

  Therefore, in order to solve the above-described problems, the present invention responds to the demand for higher printing speed of thermal transfer, higher density and higher quality of thermal transfer images, improved transfer sensitivity in printing, higher temperature and higher temperature. It is an object of the present invention to provide a thermal transfer sheet that prevents the occurrence of abnormal transfer, wrinkles and the like even under an environment such as in a humidity.

Invention of claim 1, the heat-resistant slip layer provided on one surface of the substrate, the adhesive layer on the other surface of the substrate, the thermal transfer sheet obtained by sequentially forming a dye layer, the adhesive layer is polyvinylpyrrolidone A resin, a vinyl acetate-modified polyvinyl pyrrolidone resin, or a styrene-modified polyvinyl pyrrolidone resin, and a vinyl acetate-modified or styrene- modified polyvinyl pyrrolidone resin in a proportion of 10% to 50% with respect to the total solid content of the adhesive layer. It is characterized by being.

The invention according to claim 2 is characterized in that the adhesive layer according to claim 1 has a coating amount of 0.01 to 0.3 g / m ² when dried.

The present invention relates to a thermal transfer sheet in which a heat-resistant slipping layer is provided on one surface of a substrate, and an adhesive layer and a dye layer are sequentially formed on the other surface of the substrate. The adhesive layer includes a polyvinylpyrrolidone resin and vinyl acetate. Since it contains a modified polyvinyl pyrrolidone resin or a styrene modified polyvinyl pyrrolidone resin and contains a vinyl acetate modified or styrene modified polyvinyl pyrrolidone resin in a proportion of 10% to 50% with respect to the total solid content of the adhesive layer, By supplementing the high moisture absorption and low moisture resistance of pyrrolidone resin with the moisture resistance of modified polyvinyl pyrrolidone resin copolymerized with polymers such as vinyl acetate and styrene, it is possible to create an environment that is under high temperature and high humidity. Even underneath, the adhesion between the dye layer and the substrate could be improved, and abnormal transfer or the like could be prevented. Further, it is preferable that the adhesive layer has a linear polymer of polyvinyl pyrrolidone and a modified polyvinyl pyrrolidone resin copolymerized with a polymer such as vinyl acetate or styrene, so that there is no abnormal transfer at the time of thermal transfer and transfer sensitivity. Is greatly improved, and a high-density thermal transfer image can be obtained without applying high energy.

  FIG. 1 shows one embodiment of the thermal transfer sheet of the present invention, and a heat-resistant slipping layer 4 is provided on one surface of a substrate 1 to improve the slipperiness of the thermal head and prevent sticking. In this structure, a linear polymer polyvinyl pyrrolidone resin and a modified polyvinyl pyrrolidone resin are mixed and contained on the other surface of the substrate 1 in this order.

Hereinafter, each layer constituting the thermal transfer sheet of the present invention will be described in detail.
(Base material)
The base material 1 of the thermal transfer sheet used in the present invention may be any material as long as it has a conventionally known degree of heat resistance and strength. For example, it has a thickness of about 0.5 to 50 μm, preferably about 1 to 10 μm. Polyethylene terephthalate film, 1,4-polycyclohexylenedimethylene terephthalate film, polyethylene naphthalate film, polyphenylene sulfide film, polystyrene film, polypropylene film, polysulfone film, aramid film, polycarbonate film, polyvinyl alcohol film, cellophane, acetic acid Examples thereof include cellulose derivatives such as cellulose, polyethylene film, polyvinyl chloride film, nylon film, polyimide film, ionomer film, and the like.

  In the above-mentioned base material, it is common to perform an adhesion treatment on the surface on which the adhesive layer and the dye layer are formed. When the plastic film of the base material is formed by applying an adhesive layer thereon, the wettability, adhesiveness, etc. of the coating solution are likely to be insufficient, and therefore, an adhesive treatment is performed. As the adhesion treatment, known resin surface modification such as corona discharge treatment, flame treatment, ozone treatment, ultraviolet treatment, radiation treatment, surface roughening treatment, chemical treatment, plasma treatment, low temperature plasma treatment, primer treatment, grafting treatment, etc. Quality technology can be applied as it is. Two or more of these treatments can be used in combination. The primer treatment can be performed, for example, by applying a primer solution to an unstretched film at the time of film formation by melt extrusion of a plastic film and then stretching the film.

  Furthermore, it is also possible to apply and form a primer layer between the base material and the adhesive layer as the base material adhesive treatment. The primer layer can be formed from a resin as shown below. Polyester resin, Polyacrylate resin, Polyvinyl acetate resin, Polyurethane resin, Styrene acrylate resin, Polyacrylamide resin, Polyamide resin, Polyether resin, Polystyrene resin, Polyethylene resin, Polypropylene Examples thereof include resins, vinyl resins such as polyvinyl chloride resins and polyvinyl alcohol resins, and polyvinyl acetal resins such as polyvinyl acetoacetal and polyvinyl butyral. However, in the thermal transfer sheet in which the adhesive layer and the dye layer are sequentially formed on the base material of the present invention, the adhesive property of the adhesive layer to the base material is sufficiently high. It is possible to directly provide an adhesive layer.

(Adhesive layer)
The adhesive layer 2 provided between the base material and the dye layer in the thermal transfer sheet of the present invention contains a modified polyvinyl pyrrolidone resin. The modified polyvinyl pyrrolidone resin is a copolymer of an N-vinyl pyrrolidone monomer and another monomer. The form of copolymerization is not particularly limited, such as random copolymerization, block copolymerization, and graft copolymerization. The N-vinyl pyrrolidone monomer mentioned above refers to N-vinyl pyrrolidone (N-vinyl-2-pyrrolidone, N-vinyl-4-pyrrolidone, etc.) and derivatives thereof. Examples thereof include those having a substituent on the pyrrolidone ring such as vinyl-3-methylpyrrolidone, N-vinyl-5-methylpyrrolidone, N-vinyl-3,3,5-trimethylpyrrolidone, N-vinyl-3-benzylpyrrolidone. .

  Examples of the monomer component copolymerized with the N-vinylpyrrolidone monomer include the following vinyl polymerizable monomers. For example, (meth) acrylic monomers such as (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, unsaturated carboxylic acids such as fumaric acid, maleic acid, itaconic acid, ethylene, Examples include propylene, vinyl chloride, vinyl acetate, vinyl alcohol, styrene, vinyl toluene, divinylbenzene, vinylidene chloride, ethylene tetrafluoride, and vinylidene fluoride. In particular, a copolymer of vinyl acetate or styrene monomer and N-vinylpyrrolidone monomer has moisture resistance, and can particularly improve the adhesion between the dye layer and the substrate under high temperature and high humidity. Therefore, it is preferably used. In the modified polyvinyl pyrrolidone resin as described above, the ratio of the N-vinyl pyrrolidone monomer component to the other monomer component to be copolymerized is 10% to 80% in molar ratio (N-vinyl pyrrolidone monomer component / N- Vinylpyrrolidone monomer component + other monomer component to be copolymerized).

  The modified polyvinyl pyrrolidone resin is contained at a ratio of 10% to 50% with respect to the total solid content of the adhesive layer, and thereby, the temperature is particularly high compared with the case of the linear polymer polyvinyl pyrrolidone resin alone. Adhesion between the dye layer and the substrate under humidity is improved. When the content ratio of the modified polyvinyl pyrrolidone resin is less than the above range, the adhesion between the dye layer and the substrate under high temperature and high humidity is lowered, and abnormal transfer or the like is likely to occur. On the other hand, when the content ratio of the modified polyvinyl pyrrolidone resin is larger than the above range, the adhesion between the dye layer and the substrate at room temperature or the like is lowered.

  The adhesive layer is composed of the modified polyvinyl pyrrolidone resin and other resins. Examples of the other resins include polyvinyl pyrrolidone resins, polyvinyl alcohol resins, and cellulose derivatives. Examples of the polyvinyl pyrrolidone resins include vinyl pyrrolidone such as N-vinyl-2-pyrrolidone and N-vinyl-4-pyrrolidone. Examples thereof include polymers (homopolymers) and copolymers thereof. In particular, a linear polymer polyvinylpyrrolidone resin is preferably used because it is highly effective in improving the transfer sensitivity in printing and has an adhesive property between the dye layer and the substrate. As the polyvinyl pyrrolidone resin, it is preferable to use one having a K value of Fickencher's formula of 60 or more, and in particular, a grade of K-60 to K-120 can be used, and the number average molecular weight is 30,000 to 280, About 000. When the polyvinyl pyrrolidone resin having a K value of less than 60 is used, the effect of improving transfer sensitivity in printing is reduced.

The adhesive layer is a mixture of the above-described modified polyvinyl pyrrolidone resin and a linear polymer polyvinyl pyrrolidone resin, and with additives added as necessary, water, alcoholic aqueous solvents Alternatively, a coating solution dissolved or dispersed in an organic solvent can be prepared and formed using a known coating means such as a gravure printing method, a screen printing method, or a reverse roll coating method using a gravure plate. Thus formed adhesive layer is 0.01 to 0.3 g / m ² approximately in coating amount at the time of drying, desirably 0.05~0.15g / m ^2. If the coating amount is small, the unevenness of the base material cannot be filled, and an uncoated part is generated, and this part becomes a trigger, and abnormal transfer occurs in which the dye layer is taken on the receiving layer side of the image receiving sheet during thermal transfer. Cheap. On the other hand, when the coating amount of the adhesive layer is larger than the above range, the adhesive layer and the dye layer are easily mixed during the dye layer coating, and the receiving layer is easily taken on the dye layer side during the thermal transfer.

(Dye layer)
In the thermal transfer sheet of the present invention, the dye layer 3 is provided on the other surface of the base material provided with a heat-resistant slipping layer on one surface via an adhesive layer. The dye layer may be composed of a single layer of one color, or a plurality of dye layers containing dyes having different hues may be repeatedly formed on the same surface of the same substrate in the surface order. The dye layer is a layer formed by supporting a heat transfer dye with an arbitrary binder. As the dye to be used, a dye that melts, diffuses or sublimates by heat, and is used in a conventionally known sublimation transfer type thermal transfer sheet can be used in the present invention. The selection is made in consideration of printing sensitivity, light resistance, storage stability, solubility in a binder, and the like.

  Examples of the dye include azomethines such as diarylmethane, triarylmethane, thiazole, merocyanine, pyrazolone methine and the like, indoaniline, acetophenone azomethine, pyrazoloazomethine, imidazolazomethine, imidazoazomethine, and pyridone azomethine. , Xanthene, oxazine, dicyanostyrene, cyanomethylene represented by tricyanostyrene, thiazine, azine, acridine, benzeneazo, pyridoneazo, thiophenazo, isothiazoleazo, pyrroleazo, pyralazo, imidazoleazo, Azos such as thiadiazole azo, triazole azo, dizazo, spiropyran, indolinospiropyran, fluoran, rhodamine lactam, naphthoquinone, anne Rakinon system include the quinophthalone like.

  As the binder for the dye layer, any conventionally known resin binder can be used. Examples of preferred binders include cellulose resins such as ethyl cellulose, hydroxyethyl cellulose, ethyl hydroxy cellulose, hydroxypropyl cellulose, methyl cellulose, cellulose acetate, and butyric acid cellulose. , Polyvinyl alcohol, polyvinyl acetate, polyvinyl butyral, polyvinyl acetal, polyvinyl pyrrolidone, polyacrylamide and other vinyl resins, polyester resins and phenoxy resins. Among these, cellulose resins, acetal resins, butyral resins, polyester resins, phenoxy resins, and the like are particularly preferable from the viewpoints of heat resistance, dye migration, and the like.

  In the present invention, the following releasable graft copolymer can be used as a release agent or binder in place of the resin binder. This releasable graft copolymer is obtained by graft polymerizing at least one releasable segment selected from a polysiloxane segment, a fluorocarbon segment, a fluorinated hydrocarbon segment, or a long-chain alkyl segment on a polymer main chain. Is. Among these, a graft copolymer obtained by grafting a polysiloxane segment to a main chain made of a polyvinyl acetal resin is particularly preferable.

The dye layer may contain the above-mentioned dyes, binders, and other various conventional additives as required. Examples of the additive include organic fine particles such as polyethylene wax and inorganic fine particles in order to improve releasability from the image receiving sheet and ink coating suitability. Such a dye layer is usually prepared by adding the above-mentioned dye, binder, and additives as necessary in an appropriate solvent, and dissolving or dispersing each component to prepare a coating solution. It can be formed by applying and drying the liquid on a substrate. As this coating method, known means such as a gravure printing method, a screen printing method, a reverse roll coating method using a gravure plate, or the like can be used. The dye layer thus formed has a coating amount at the time of drying of about 0.2 to 6.0 g / m ² , preferably about 0.3 to 3.0 g / m ² .

(Heat resistant slipping layer)
In the thermal transfer sheet of the present invention, a heat-resistant slipping layer 4 is provided on one surface of the substrate in order to prevent adverse effects such as sticking and printing wrinkles due to the heat of the thermal head. The resin for forming the thermal slipping layer may be any conventionally known resin, for example, polyvinyl butyral resin, polyvinyl acetoacetal resin, polyester resin, vinyl chloride-vinyl acetate copolymer, polyether resin, Polybutadiene resin, styrene-butadiene copolymer, acrylic polyol, polyurethane acrylate, polyester acrylate, polyether acrylate, epoxy acrylate, urethane or epoxy prepolymer, nitrocellulose resin, cellulose nitrate resin, cellulose acetate propionate resin, cellulose Acetate butyrate resin, cellulose acetate hydrodiene phthalate resin, cellulose acetate resin, aromatic polyamide resin, polyimide resin, polyamideimide resin, poly Boneto resins, and chlorinated polyolefin resins.

  The slipperiness imparting agent added to or overcoating the heat resistant slipping layer made of these resins includes phosphate ester, silicone oil, graphite powder, silicone graft polymer, fluorine graft polymer, acrylic silicone graft polymer, acrylic siloxane, aryl Examples thereof include silicone polymers such as siloxane, but a layer made of a polyol, for example, a polyalcohol polymer compound, a polyisocyanate compound, and a phosphate ester compound, and it is more preferable to add a filler.

The heat-resistant slipping layer is prepared by dissolving or dispersing the above-described resin, slipperiness-imparting agent, and filler in an appropriate solvent on the base sheet to prepare a heat-resistant slipping layer coating solution. This can be formed by coating with a forming means such as gravure printing, screen printing, reverse roll coating using a gravure plate, and drying. The coating amount of the heat-resistant slip layer is a ^{solid, 0.1g / m 2 ~3.0g / m} 2 is preferred.

Next, an Example and a comparative example are given and this invention is further explained in full detail. In the text, “part” or “%” is based on mass unless otherwise specified. The adhesive layer coating solution having the following composition is dried on the untreated polyethylene terephthalate film (PET) (Mitsubishi Chemical Polyester Film Co., Ltd., Diafoil K880) having a thickness of 4.5 μm by gravure coating. It was applied so that the amount applied was 0.03 g / m ² and dried at 110 ° C. for 1 minute to form an adhesive layer.

Further, on the adhesive layer, a dye layer coating solution having the following composition was applied by gravure coating so that the dry coating amount was 0.8 g / m ² and dried to form a dye layer. A thermal transfer sheet is prepared. In addition, a heat resistant slipping layer coating solution having the following composition is applied to the other surface of the base material in advance by gravure coating and dried so that the dry coating amount becomes 1.0 g / m ² . A layer was formed.

<Adhesive layer composition A>
Polyvinyl pyrrolidone resin (K-90, manufactured by ISP Ltd.) 9 parts Vinyl acetate modified polyvinyl pyrrolidone resin (I-335, manufactured by ISP Ltd., solid content 50%) 2 parts Methyl ethyl ketone 83 parts Isopropyl alcohol 82 parts

<Dye layer composition liquid 1>
C. I. Solvent Blue 22 5.5 parts Polyvinyl acetal resin 3.0 parts (S-REC KS-5 Sekisui Chemical Co., Ltd.)
Methyl ethyl ketone 22.5 parts Toluene 68.2 parts

<Heat resistant slipping layer composition>
13.6 parts of polyvinyl butyral resin (manufactured by SREC BX-1 by Sekisui Chemical Co., Ltd.)
0.6 parts of polyisocyanate curing agent (Takenate D218, Takeda Pharmaceutical Company Limited)
Phosphate 0.8 parts (Plysurf A208S, Daiichi Kogyo Seiyaku Co., Ltd.)
Methyl ethyl ketone 42.5 parts Toluene 42.5 parts

A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. The adhesive layer coating solution used in Example 1 was applied to the surface opposite to the surface on which the heat-resistant slipping layer of the substrate was provided, by gravure coating so that the dry coating amount was 0.05 g / m ^2. And dried to form an adhesive layer. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce the thermal transfer sheet of Example 2.

A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. The adhesive layer coating solution used in Example 1 was applied to the surface opposite to the surface on which the heat-resistant slipping layer of the substrate was provided, by gravure coating so that the dry coating amount was 0.1 g / m ^2. And dried to form an adhesive layer. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce the thermal transfer sheet of Example 3.

A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. The adhesive layer coating solution used in Example 1 was applied to the surface opposite to the surface on which the heat-resistant slipping layer of the substrate was provided, by gravure coating so that the dry coating amount was 0.2 g / m ^2. And dried to form an adhesive layer. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce the thermal transfer sheet of Example 4.

A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. The adhesive layer coating solution used in Example 1 was applied to the surface opposite to the surface on which the heat-resistant slipping layer of the substrate was provided, by gravure coating so that the dry coating amount was 0.25 g / m ^2. And dried to form an adhesive layer. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce the thermal transfer sheet of Example 5.

A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. The adhesive layer coating solution used in Example 1 was applied by gravure coating on the surface opposite to the surface on which the heat-resistant slip layer of the substrate was provided so that the dry coating amount was 0.35 g / m ^2. And dried to form an adhesive layer. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce the thermal transfer sheet of Example 6.

A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. An adhesive layer coating solution having the following composition is applied to the surface of the substrate opposite to the surface on which the heat-resistant slip layer is provided by gravure coating and dried to a dry coating amount of 0.06 g / m ^2. Thus, an adhesive layer was formed. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce the thermal transfer sheet of Example 7.

<Adhesive layer composition B>
Polyvinylpyrrolidone resin (K-90, manufactured by ISP Ltd.) 5 parts Vinyl acetate-modified polyvinylpyrrolidone resin (I-335, manufactured by ISP Ltd., solid content 50%) 10 parts Methyl ethyl ketone 83 parts Isopropyl alcohol 78 parts

A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. The adhesive layer coating solution having the following composition is applied to the surface of the substrate opposite to the surface on which the heat-resistant slip layer is provided by gravure coating and dried to a dry coating amount of 0.03 g / m ^2. Thus, an adhesive layer was formed. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce the thermal transfer sheet of Example 8.

<Adhesive layer composition C>
Polyvinylpyrrolidone resin (K-90, manufactured by ISP Ltd.) 9 parts Vinyl acetate-modified polyvinylpyrrolidone resin (S-630, manufactured by ISP Ltd.) 1 part Methyl ethyl ketone 83 parts Isopropyl alcohol 83 parts

A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. The adhesive layer coating solution used in Example 8 was applied to the surface opposite to the surface on which the heat-resistant slipping layer of the substrate was provided, by gravure coating so that the dry coating amount was 0.05 g / m ^2. And dried to form an adhesive layer. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce a thermal transfer sheet of Example 9.

A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. The adhesive layer coating solution used in Example 8 was applied to the surface opposite to the surface on which the heat-resistant slipping layer of the substrate was provided, by gravure coating so that the dry coating amount was 0.2 g / m ^2. And dried to form an adhesive layer. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce the thermal transfer sheet of Example 10.

A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. The adhesive layer coating solution used in Example 8 was applied to the surface opposite to the surface on which the heat-resistant slip layer of the substrate was provided, by gravure coating so that the dry coating amount was 0.35 g / m ^2. And dried to form an adhesive layer. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce the thermal transfer sheet of Example 11.

A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. The adhesive layer coating solution having the following composition is applied to the surface of the substrate opposite to the surface on which the heat resistant slipping layer is provided by gravure coating and dried to a dry coating amount of 0.2 g / m ^2. Thus, an adhesive layer was formed. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce the thermal transfer sheet of Example 12.

<Adhesive layer composition liquid D>
Polyvinylpyrrolidone resin (K-90, manufactured by ISP Ltd.) 7 parts Vinyl acetate-modified polyvinylpyrrolidone resin (S-630, manufactured by ISP Ltd.) 3 parts Methyl ethyl ketone 83 parts Isopropyl alcohol 83 parts

A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. An adhesive layer coating solution having the following composition is applied to the surface of the substrate opposite to the surface on which the heat-resistant slip layer is provided by gravure coating and dried to a dry coating amount of 0.06 g / m ^2. Thus, an adhesive layer was formed. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce the thermal transfer sheet of Example 13.

<Adhesive layer composition liquid E>
Polyvinylpyrrolidone resin (K-90, manufactured by ISP Ltd.) 5 parts Vinyl acetate-modified polyvinylpyrrolidone resin (S-630, manufactured by ISP Ltd.) 5 parts Methyl ethyl ketone 83 parts Isopropyl alcohol 83 parts

A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. The adhesive layer coating solution having the following composition is applied to the surface of the substrate opposite to the surface on which the heat-resistant slip layer is provided by gravure coating and dried to a dry coating amount of 0.03 g / m ^2. Thus, an adhesive layer was formed. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce the thermal transfer sheet of Example 14.

<Adhesive layer composition liquid F>
Polyvinyl pyrrolidone resin (K-90, manufactured by ISP Ltd.) 9 parts Styrene-modified polyvinyl pyrrolidone resin (ANTARA 430, manufactured by ISP Ltd., solid content 40%) 2.5 parts Water 81.5 parts Isopropyl alcohol 83 parts

A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. The adhesive layer coating solution used in Example 14 was applied by gravure coating on the surface opposite to the surface on which the heat-resistant slipping layer of the substrate was provided so that the dry coating amount was 0.05 g / m ^2. And dried to form an adhesive layer. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce the thermal transfer sheet of Example 15.

A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. The adhesive layer coating solution used in Example 14 was applied by gravure coating on the surface opposite to the surface on which the heat-resistant slip layer of the substrate was provided so that the dry coating amount was 0.2 g / m ^2. And dried to form an adhesive layer. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce the thermal transfer sheet of Example 16.

A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. The adhesive layer coating solution used in Example 14 was applied by gravure coating on the surface opposite to the surface on which the heat-resistant slipping layer of the substrate was provided so that the dry coating amount was 0.35 g / m ^2. And dried to form an adhesive layer. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce the thermal transfer sheet of Example 17.

A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. An adhesive layer coating solution having the following composition is applied to the surface of the substrate opposite to the surface on which the heat-resistant slip layer is provided by gravure coating and dried to a dry coating amount of 0.06 g / m ^2. Thus, an adhesive layer was formed. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce the thermal transfer sheet of Example 18.

<Adhesive layer composition liquid G>
Polyvinylpyrrolidone resin (K-90, manufactured by ISP Ltd.) 5 parts Styrene-modified polyvinylpyrrolidone resin (ANTARA430, manufactured by ISP Ltd., solid content 40%) 12.5 parts Water 75.5 parts Isopropyl alcohol 83 parts

(Comparative Example 1)
A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. An adhesive layer coating solution having the following composition is applied to the surface of the substrate opposite to the surface on which the heat-resistant slip layer is provided by gravure coating and dried to a dry coating amount of 0.06 g / m ^2. Thus, an adhesive layer was formed. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce a thermal transfer sheet of Comparative Example 1.

<Adhesive layer composition liquid H>
Polyvinyl pyrrolidone resin (K-90, manufactured by ISP Ltd.) 10 parts Methyl ethyl ketone 83 parts Isopropyl alcohol 83 parts

(Comparative Example 2)
A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. An adhesive layer coating solution having the following composition is applied to the surface of the substrate opposite to the surface on which the heat-resistant slip layer is provided by gravure coating and dried to a dry coating amount of 0.06 g / m ^2. Thus, an adhesive layer was formed. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce a thermal transfer sheet of Comparative Example 2.

<Adhesive layer composition liquid I>
Polyvinylpyrrolidone resin (K-90, manufactured by ISP Ltd.) 9.5 parts Vinyl acetate-modified polyvinylpyrrolidone resin (I-335, manufactured by ISP Ltd., solid content 50%) 1 part Methyl ethyl ketone 83 parts Isopropyl alcohol 82.5 parts

(Comparative Example 3)
A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. An adhesive layer coating solution having the following composition is applied to the surface of the substrate opposite to the surface on which the heat-resistant slip layer is provided by gravure coating and dried to a dry coating amount of 0.06 g / m ^2. Thus, an adhesive layer was formed. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce a thermal transfer sheet of Comparative Example 3.

<Adhesive layer composition liquid J>
Polyvinylpyrrolidone resin (K-90, manufactured by ISP Ltd.) 2.5 parts Vinyl acetate modified polyvinylpyrrolidone resin (I-335, manufactured by ISP Ltd., solid content 50%) 15 parts Methyl ethyl ketone 83 parts Isopropyl alcohol 75.5 parts

(Comparative Example 4)
A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. An adhesive layer coating solution having the following composition is applied to the surface of the substrate opposite to the surface on which the heat-resistant slip layer is provided by gravure coating and dried to a dry coating amount of 0.06 g / m ^2. Thus, an adhesive layer was formed. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce a thermal transfer sheet of Comparative Example 4.

<Adhesive layer composition liquid K>
Polyvinylpyrrolidone resin (K-90, manufactured by ISP Ltd.) 9.5 parts Vinyl acetate modified polyvinylpyrrolidone resin (S-630, manufactured by ISP Ltd.)
0.5 parts Methyl ethyl ketone 83 parts Isopropyl alcohol 83 parts

(Comparative Example 5)
A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. An adhesive layer coating solution having the following composition is applied to the surface of the substrate opposite to the surface on which the heat-resistant slip layer is provided by gravure coating and dried to a dry coating amount of 0.06 g / m ^2. Thus, an adhesive layer was formed. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce a thermal transfer sheet of Comparative Example 5.

<Adhesive layer composition liquid L>
Polyvinylpyrrolidone resin (K-90, manufactured by ISP Ltd.) 2.5 parts Vinyl acetate-modified polyvinylpyrrolidone resin (S-630, manufactured by ISP Ltd.)
7.5 parts Methyl ethyl ketone 83 parts Isopropyl alcohol 83 parts

(Comparative Example 6)
A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. An adhesive layer coating solution having the following composition is applied to the surface of the substrate opposite to the surface on which the heat-resistant slip layer is provided by gravure coating and dried to a dry coating amount of 0.06 g / m ^2. Thus, an adhesive layer was formed. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce a thermal transfer sheet of Comparative Example 6.

<Adhesive layer composition liquid M>
Polyvinylpyrrolidone resin (K-90, manufactured by ISP Ltd.) 9.5 parts Styrene-modified polyvinylpyrrolidone resin (ANTARA430, manufactured by ISP Ltd., solid content 40% 1.25 parts Water 82.25 parts Isopropyl alcohol 83 parts

(Comparative Example 7)
A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. An adhesive layer coating solution having the following composition is applied to the surface of the substrate opposite to the surface on which the heat-resistant slip layer is provided by gravure coating and dried to a dry coating amount of 0.06 g / m ^2. Thus, an adhesive layer was formed. Further, a dye layer is formed on the adhesive layer in the same manner as in Example 1 to produce a thermal transfer sheet of Comparative Example 7.

<Adhesive layer composition liquid N>
Polyvinyl pyrrolidone resin (K-90, manufactured by ISP Ltd.) 2.5 parts Styrene-modified polyvinyl pyrrolidone resin (ANTARA 430, manufactured by ISP Ltd.)
18.75 parts Water 71.75 parts Isopropyl alcohol 83 parts

(Comparative Example 8)
A PET film substrate having the same conditions as in Example 1 was used, and a heat-resistant slipping layer similar to that in Example 1 was previously formed on the other surface of the substrate. A dye layer is directly formed in the same manner as in Example 1 without providing an adhesive layer on the surface opposite to the surface on which the heat-resistant slip layer of the substrate is provided, and a thermal transfer sheet of Comparative Example 8 is produced.

  Using the thermal transfer sheets of Examples and Comparative Examples prepared above, each evaluation of heat-resistant adhesion at room temperature and high temperature and high humidity and adhesion to an image receiving sheet was performed by the following methods.

(Heat resistant adhesiveness 1)
A thermal transfer sheet as a sample of Examples and Comparative Examples is pasted on a mount with the dye layer side facing up (the mount and the heat-resistant slipping layer are in contact with each other). And the reference ribbon 1 corresponding to the sample (the condition of the dye layer is the same, the base material is made by Mitsubishi Chemical Polyester Film Co., Ltd., and the dye layer is provided directly on the easy-foil-treated PET film of Diafoil K230E) Attached to different positions on the same mount with the dye layer surface facing up, the sample and the reference ribbon are folded back so that the dye layer surfaces are in contact with each other, temperature 100 to 130 ° C., pressure 34.3 × 10 Heat sealing was performed at ⁴ Pa and a pressurization time of 2 seconds, both were peeled off, and the remaining state (taken state) of each dye layer of the sample and the reference ribbon 1 was visually examined, and evaluated according to the following criteria. did. However, both the thermal transfer sheet and the reference ribbon 1 as the samples of the examples and comparative examples are subjected to the heat sealing in a state of being left at room temperature, and both the thermal transfer sheet and the reference ribbon 1 as the samples are 40 ° C. After standing in a 90% RH environment for 16 hours, the above-described heat sealing was conducted in two ways.

○: The area of the dye layer remaining on the sample side is larger than the area remaining on the reference ribbon side.
Δ: The area of the dye layer remaining on the sample side is equal to the area remaining on the reference ribbon side.
X: The area of the dye layer remaining on the sample side is smaller than the area remaining on the reference ribbon side.

(Heat resistant adhesion 2)
A thermal transfer sheet as a sample of Examples and Comparative Examples is pasted on a mount with the dye layer side facing up (the mount and the heat-resistant slipping layer are in contact with each other). Then, the reference ribbon 2 corresponding to the sample (the conditions of the dye layer are the same, and the base material is a polyvinyl pyrrolidone resin (K-90, ISP) on the surface of a PET film of Diafoil K880 manufactured by Mitsubishi Chemical Polyester Film Co., Ltd. Ltd.) (adhesive layer equivalent to the adhesive layer condition of Comparative Example 1 provided to be 0.06 g / m ² when dried) with the dye layer side up and different positions on the same mount And the sheet is folded so that the sample and the dye layer surface of the reference ribbon are in contact with each other, and heat sealing is performed at a temperature of 100 to 130 ° C., a pressure of 34.3 × 10 ⁴ Pa, and a pressurization time of 2 seconds. Both were peeled off, and the remaining state (taken state) of each dye layer of the sample and the reference ribbon 2 was visually examined and evaluated according to the same standard as the heat resistant adhesiveness 1 described above. However, both the thermal transfer sheet and the reference ribbon 2 as the samples of the example and the comparative example are subjected to the heat seal in a state of being left at room temperature, and both the thermal transfer sheet and the reference ribbon 2 as the samples are 40 ° C. After standing in a 90% RH environment for 16 hours, the above-described heat sealing was conducted in two ways.

(Adhesiveness with image receiving sheet)
The dye layer surface of each of the thermal transfer sheets obtained in the above Examples and Comparative Examples was superposed so that the image receiving surface of the image receiving sheet of Olympus Corporation's digital color printer P-200 dedicated standard set was in contact, and the temperature was 100 ~ 130 ° C, pressure 34.3 × 10 ⁴ Pa, pressurization time 2 sec, heat seal, peel both, and visually check the peeled state of the dye layer of the sample and the image receiving layer of the image receiving sheet. Evaluation was made based on the criteria. In this case, the heat transfer sheet and the image receiving sheet were left to stand at room temperature, and the heat sealing was performed.

○: The image receiving layer is not peeled off on the dye layer side, and there is no abnormality.
X: The image receiving layer is peeled off on the dye layer side.

＊１；変性ＰＶＰ添加量は、ポリビニルピロリドン樹脂（Ｋ−９０、ＩＳＰ Ｌｔｄ．製）と合わせた全体に対する添加量の割合である。但し、固形分基準での割合である。 The evaluation results of the above examples and comparative examples are shown in Table 1 below.

* 1; The modified PVP addition amount is a ratio of the addition amount to the whole combined with the polyvinylpyrrolidone resin (K-90, manufactured by ISP Ltd.). However, the ratio is based on solid content.

From the above results, the modified polyvinyl pyrrolidone resin is contained in the adhesive layer in a proportion of 10% to 50% with respect to the total solid content of the adhesive layer, and the coating amount of the adhesive layer is 0.05 to 0.00 in a dry state. Examples 2, 3, 4, 5, 7, 9, 10, 12, 13, 15, 16 which are 25 g / m ² are the heat resistant adhesiveness 1, 2 and the adhesiveness to the image receiving sheet. Good results. In Examples 1, 8, and 14, the modified polyvinyl pyrrolidone resin is contained in the adhesive layer at a ratio of 10% with respect to the total solid content of the adhesive layer, and the coating amount of the adhesive layer is 0.03 g / m ² in a dry state. However, although the adhesiveness is the same as that of the reference ribbon at room temperature of heat resistant adhesiveness 2, the adhesiveness between the substrate and the dye layer was higher than that of the reference ribbon at high temperature and high humidity. In Examples 6, 11, and 17, the adhesive layer contains the modified polyvinyl pyrrolidone resin at a ratio of 10% with respect to the total solid content of the adhesive layer. 35 g / m ² , the amount of coating is too large, and it is easy to mix the adhesive layer and the dye layer at the time of coating the dye layer, so that the receiving layer is easily taken on the dye layer side at the time of thermal transfer. . However, the above heat-resistant adhesiveness 1, 2 is good.

  In Comparative Example 1, the adhesive layer did not contain any modified polyvinylpyrrolidone resin, and it was found that, in heat resistant adhesiveness 1, the adhesiveness between the dye layer and the substrate under high temperature and high humidity was lowered. In Comparative Examples 2, 4, and 6, the modified polyvinyl pyrrolidone resin is contained in the adhesive layer at a ratio of 5% with respect to the total solid content of the adhesive layer, but the adhesion between the dye layer and the substrate under high temperature and high humidity It turned out that the sex was falling. Further, in Comparative Examples 3, 5, and 7, the modified polyvinyl pyrrolidone resin is contained in the adhesive layer in a ratio of 75% with respect to the total solid content of the adhesive layer, but the content ratio of the modified polyvinyl pyrrolidone resin is too large. Since the ratio of the chain polymer polyvinylpyrrolidone resin is small, the adhesiveness is lower than that of the reference ribbon at room temperature with heat resistant adhesiveness 2. In Comparative Example 8, a dye layer was directly provided on the base material without providing an adhesive layer. With respect to heat resistance, the dye layer and the base material at room temperature and high temperature and high humidity were used. Adhesion is reduced.

It is a schematic sectional drawing which shows one embodiment which is the thermal transfer sheet of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base material 2 Adhesive layer 3 Dye layer 4 Heat resistant slipping layer

Claims (2)

In a thermal transfer sheet in which a heat-resistant slipping layer is provided on one surface of a base material, and an adhesive layer and a dye layer are sequentially formed on the other surface of the base material, the adhesive layer includes a polyvinyl pyrrolidone resin and a vinyl acetate modified polyvinyl pyrrolidone resin. Or a styrene-modified polyvinylpyrrolidone resin and a vinyl acetate-modified or styrene- modified polyvinylpyrrolidone resin in a proportion of 10% to 50% with respect to the total solid content of the adhesive layer. The thermal transfer sheet according to claim 1, wherein the adhesive layer has a coating amount of 0.01 to 0.3 g / m ² when dried.

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