JP3042531B2 - Heat transfer sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a sheet to be thermally transferred.

[Conventional technology]

The thermal recording method of recording desired information by heating the thermal transfer sheet with a thermal head and transferring dyes and the like on the thermal transfer sheet onto the thermal transfer sheet is used as information recording means in various fields,
In recent years, it has also been used for creating transmissive originals used in projection devices such as overhead projectors (hereinafter abbreviated as OHP). As this type of heat transfer sheet, for example, thickness
There is used a sheet-like substrate made of polyethylene terephthalate having a thickness of about 100 μm, on which a receiving layer for receiving a dye or the like transferred from a thermal transfer sheet is formed.

[Problems to be solved by the invention]

However, in the conventional heat transfer sheet, the heat transfer sheet is easily curled due to heat at the time of transfer by the thermal head, and when the curl occurs, the transfer of the heat transfer sheet in the transfer recording apparatus becomes poor, and as a document for OHP. When used, distortion occurs in the projected image when subjected to OHP. Especially when performing multiple overprinting such as color transfer recording, curling becomes severe, and not only the projected image becomes severely distorted, but also on the receiving layer. However, there is a problem that an image transferred and recorded on the image forming apparatus has a color shift.

[Means for solving the problem]

The present invention has been made in view of the above points, and does not cause curl due to heat at the time of image transfer by a thermal head, can improve the sheet feeding at the time of image transfer, and transfer the image onto the receiving layer. It is an object of the present invention to provide a heat transfer sheet that can create an OHP document without causing a color shift in an image to be produced or causing a distortion in a projected image even when subjected to OHP.

That is, the present invention provides (1) a receiving layer for receiving a dye migrating from a thermal transfer sheet, a base material on which the receiving layer is supported, a space between the receiving layer and the base material, and / or a back surface of the base material. A resin layer having a small heat shrinkage ratio of 100 ° C., 10-minute heat shrinkage ratio of -1.0 to 1.5% and a softening temperature of 90 ° C. or higher provided in JIS-K-6733, A heat transfer sheet, wherein the resin layer is selected from polyacryl, polyurethane, polycarbonate, vinylidene chloride, polyamide, and polyester; (2) a substrate having a receptivity for dyes transferred from the heat transfer sheet On the back side of JIS-K-6734, a resin layer with a small heat shrinkage of 100 ° C for 10 minutes, a resin with a heat shrinkage of -1.0 to 1.5% and a softening temperature of 90 ° C or more is provided. , The resin layer is made of polyacryl, polyure Tan, polycarbonate, vinylidene chloride, polyamide, heat transfer sheet characterized by being selected from polyester,
It is the gist.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of a heat transfer sheet 1 according to the present invention. The heat transfer sheet 1 is provided with a receiving layer 3 on one surface of a base material 2 and a side of the base material 2 on which the receiving layer 3 is provided. On the opposite side, a resin layer 5 having a small heat shrinkage is provided via a primer layer 4.

As the substrate 2, a film or sheet such as plastic, synthetic paper, or cellulose fiber paper is used. As a plastic film or sheet, for example, polyethylene terephthalate, polyolefin, polyvinyl chloride, polyvinylidene chloride, polystyrene, polycarbonate,
Polyphenylenesulfan, polyethersulfone,
Films and sheets made of polyetheretherketone, polyetherimide, acrylic resin such as polyarylate and polymethylmethacrylate can be used, and white films, sheets and the like formed by adding a filler to these films and sheets can be used. Foamed films and sheets subjected to fine foaming can also be used, but for OHP, those having high transparency and high heat resistance are preferred, and polyethylene terephthalate is usually used. As a synthetic paper, polyolefin resin or other synthetic resin as a resin component,
Add an inorganic filler and the like to this, mix, and form a film,
Examples thereof include those obtained by extrusion molding into a sheet shape, resin films of polystyrene, polyester, polyolefin, and the like, and those manufactured by applying an extender to the surface of the sheet. In addition, high quality paper as cellulose fiber paper,
Coated paper, cast-coated paper, synthetic rubber latex or synthetic resin emulsion impregnated paper, and the like can be used. The thickness of the substrate 2 is preferably 30 to 200 μm, particularly preferably 50 to 150 μm.

The material forming the receiving layer 3 receives an image of a dye transferred from the thermal transfer sheet, for example, a sublimable disperse dye,
Although what can maintain the image formed by receiving is used, any type can be used as long as it is conventionally used for the receiving layer of this type of heat transfer sheet. is there. Such materials include, for example, the following synthetic resins (a) to (e) alone or a mixture of two or more.

(A) Those having an ester bond.

Polyester, polyacrylate, polycarbonate, polyvinyl acetate, styrene acrylate resin,
Vinyl toluene acrylate resin, etc.

(B) Those having a urethane bond.

 Polyurethane and the like.

(C) Those having an amide bond.

 Polyamide (nylon, etc.).

(D) Those having a urea bond.

 Urea resin and the like.

(E) Others having a highly polar bond.

Polycaprolactone, polystyrene, polyvinyl chloride, polyacrylonitrile, etc.

The receiving layer 3 can also be constituted by a mixed resin of a saturated polyester and a vinyl chloride-vinyl acetate copolymer. In this case, the vinyl chloride-vinyl acetate copolymer preferably has a vinyl chloride component content of 85 to 97% by weight and a degree of polymerization of about 200 to 800. Not only the copolymer of vinyl chloride and vinyl acetate only, but also a vinyl alcohol component,
It may contain a maleic acid component.

Further, the receiving layer 3 may be made of a styrene resin other than the polystyrene. As the styrene-based resin, for example, styrene, α-methylstyrene, homopolymer or copolymer of styrene-based monomers such as vinyltoluene, or these styrene-based monomers and other monomers, for example, acrylate, methacrylate, Examples thereof include copolymers with acrylic or methacrylic monomers such as acrylonitrile and methacrylonitrile, and maleic anhydride.

In the present invention, if necessary, an ultraviolet absorber may be added to the receiving layer 3. Addition of the ultraviolet absorber improves the weather resistance of the dye transferred from the thermal transfer sheet and dyed on the receptor layer. Examples of the ultraviolet absorber include a benzophenone type, a hindered amine type, and a benzotriazole type. The addition amount is about 0.05 to 5 parts by weight based on 100 parts by weight of the resin constituting the receiving layer 3.

The receiving layer 3 may optionally contain a release agent for the purpose of improving the releasability from the thermal transfer sheet. Examples of the release agent include solid waxes such as polyethylene wax, amide wax, and Teflon powder, fluorine-based and phosphate-based surfactants, and silicone oil. Silicone oil is preferred. Oily silicone oils may be used, but curable silicone oils are preferred. Examples of the curable silicone oil include a reaction curable type, a photocurable type, and a catalyst curable type, and a reaction curable type silicone oil is particularly preferable. The reaction-curable silicone oil is preferably one obtained by reacting and curing an amino-modified silicone oil and an epoxy-modified silicone oil. The addition amount of these curable silicone oils is preferably 0.5 to 30 parts by weight based on 100 parts by weight of the resin constituting the receiving layer 3. The release agent is not limited to the case where the release agent is added to the receiving layer 3. The release agent may be formed by dissolving or dispersing the release agent in an appropriate solvent on the surface of the receiving layer 3 and drying. Good. As the release agent constituting the release agent layer, the above-mentioned cured product of the amino-modified silicone oil and the epoxy-modified silicone oil is particularly preferable.
The release agent layer is preferably formed to a thickness of 0.01 to 5 µ, particularly 0.05 to 2 µ. The release agent layer may be provided on a part of the surface of the receiving layer 3 or on the entire surface. However, when the release agent layer is provided on a part of the surface of the receiving layer 3, the release agent layer is provided. Dot impact recording, heat-sensitive melting transfer recording, or recording with a pencil or the like can be performed on the portion where no release agent layer is provided. Sublimation transfer recording is performed on the portion where the release agent layer is provided, and the portion where the release agent layer is not provided. For example, the sublimation transfer recording method and another recording method can be used in combination, such as recording by another recording method.

When the base material 2 is made of a resin such as vinyl chloride, polyester, vinyl chloride-vinyl acetate copolymer, and vinyl chloride-acrylic polymer, the surface of these resins has dye receptivity and mold releasability. The receiving layer 3 may not be provided separately.

The resin layer 5 having a small heat shrinkage ratio provided on the surface of the base material 2 opposite to the surface on which the receiving layer 3 is provided with the primer layer 4 interposed therebetween is subjected to heat shrinkage in JIS-K-6734 (100 ° C., 10 minutes). Made of a heat-resistant or semi-heat-resistant resin having a modulus of -1.0 to 1.5% and a softening temperature of 90 ° C or higher, polyacryl, polyurethane, polycarbonate, vinylidene chloride, polyamide,
A resin selected from polyester is used. The thickness of the resin layer 5 having a small heat shrinkage is preferably 1 to 10 μm, particularly preferably 3 to 10 μm. The resin layer 5 having a small heat shrinkage can be formed by a method of applying a molten resin or a resin dissolved in a solvent, or a method of forming and bonding these resins into a film or a sheet. The primer layer 4 is provided for the purpose of improving the adhesion between the base material 2 and the resin layer 5 having a small heat shrinkage. Examples of the resin constituting the primer layer 4 include polyurethane, polyacryl, polyester, and epoxy. No. The primer layer 4 is a substrate 2
When the adhesiveness between the material and the resin layer 5 having a small heat shrinkage ratio is good due to the material of the material and the resin layer 5, the material need not always be provided.

As shown in FIG. 2, the heat transfer sheet 1 of the present invention can be provided with a resin layer 5 having a small heat shrinkage ratio between the base material 2 and the receiving layer 3. It can also be provided both between the layers 3 and on the back side of the substrate 2.

As shown in FIGS. 3 and 4, the heat transfer sheet 1 of the present invention is provided on the back side of the resin layer 5 or the base material 2 having a small heat shrinkage rate via an adhesive layer 6 as necessary. The support sheet 7 for improving the paper passing property in the transfer device can be peelably adhered. Support sheet 7
May be either transparent or opaque, and the material used is, for example, synthetic paper, cellulose fiber paper, synthetic resin sheet, or the like. Examples of the synthetic paper include a type obtained by inserting a filler into a polyolefin resin, extruding and stretching, and a type obtained by applying a mixture of a filler and a binder to a polyolefin, polystyrene, or polyester sheet. As the cellulose fiber paper, high-quality paper, coated paper, art paper, cast-coated paper, processed paper impregnated with or coated with synthetic resin or rubber, or processed paper obtained by extrusion lamination of polyethylene or the like can be used. As a synthetic resin sheet, a single transparent film such as polyethylene terephthalate, polypropylene, hard vinyl chloride, etc., a sheet extruded by adding a filler such as clay, calcium carbonate, titanium oxide, or a resin containing the above resin or filler Laminated paper extruded onto high quality paper or the like, or those having fine irregularities formed on the surface thereof by sandblasting, embossing or the like are used.

By providing a slippery layer on the back surface of the support sheet 7, the paper passing property can be further improved. The lubricating layer can be formed by applying a methacrylate resin such as methyl methacrylate or a corresponding acrylate resin, or a vinyl resin such as vinyl chloride-vinyl acetate copolymer.

The pressure-sensitive adhesive layer 6 can be composed of a normal pressure-sensitive adhesive such as a polyacrylate, an acrylic copolymer, a natural rubber, a synthetic rubber, a petroleum resin, or a block copolymer such as SIS or SBR. In order to facilitate the peeling of the sheet 7, a weakly tacky adhesive is preferable. As the weak pressure-sensitive adhesive, a material having low heat shrinkage and a property of weak adhesion to the resin layer 5 or the substrate 2 may be selected and used, or inorganic particles may be kneaded into the usual pressure-sensitive adhesive as described above, or a release agent may be used. Are mixed to give a releasability.

A detection mark for positioning in a transfer device at the time of transfer can be printed on the back surface of the heat transfer sheet 1 of the present invention. There is a case of the back surface of the small resin layer or a case of the back surface of the support sheet 7).

Hereinafter, the present invention will be described in more detail with reference to specific examples. Incidentally, all the formulations in the examples are parts by weight.

Example 1, Comparative Example 1 Transparent PET (T-75, manufactured by Toray Co., Ltd.) having a thickness of 75 μm was used as a base material, and the following ink composition for forming a receptor layer was dried at a coating amount of 5 g / m ² . After coating with a bar coater and drying with a drier, the oven
After drying for a minute, a receiving layer was formed.

Ink composition for forming a receiving layer ・ Polyester (Vylon 600: manufactured by Toyobo Co., Ltd.) 4.0 parts ・ Vinyl chloride-vinyl acetate copolymer (# 1000A: manufactured by Denki Kagaku Kogyo) 6.0 parts ・ Amino-modified silicone (X-22-3050C: Shin-Etsu Chemical Co., Ltd. 0.2 parts Epoxy-modified silicone (X-22-3000E: Shin-Etsu Chemical Co., Ltd.) 0.2 parts Solvent (MEK: Toluene = 1: 1) 89.6 parts Next side opposite to the side on which this receptor layer is provided On the surface of the primer of the following composition is coated at 1 g / m ² when dried with a bar coater
After drying at Doraia was applied so that, by further applying a small resin layer forming ink composition with heat shrinkage of the following composition so that a bar coater and dried at 3 g / m ² Doraia After drying in the oven, further in the oven 80
The resultant was dried at 10 ° C. for 10 minutes to obtain a heat transferable sheet.

Primer composition • Polyester polyol (Adcoat AD335AE: manufactured by Toyo Morton) 15 parts • Solvent (MEK: dioxane = 2: 1) 85 parts Ink composition for forming resin layer with low heat shrinkage • Acrylic resin (BR-85: Mitsubishi Rayon) 10 parts ・ Solvent (MEK) 90 parts On the other hand, a 4.5μ thick polyester film with a heat-resistant lubricating layer made of thermosetting acrylic resin on one side (Toray:
And a heat transfer layer forming ink composition having the following composition applied to the surface opposite to the side provided with the heat-resistant lubricating layer so that the coated amount after drying is 1 g / m ^2. Thus, a thermal transfer layer was formed to obtain a thermal transfer sheet.

Yellow ink composition for thermal transfer layer formation ・ Disperse dye (Macrolex Yellow 6G: manufactured by Bayer) (Disperse Yellow 201) 5.5 parts ・ Polyvinyl butyral (ESLEC BX-1: manufactured by Sekisui Chemical) 4.5 parts ・ Methyl ethyl ketone 45 parts ・ Toluene 45 parts Using the above-mentioned heat transfer sheet and the above-mentioned heat transfer sheet, transfer was performed under the following conditions, and the degree of curl was examined. As well as thickness
100μ transparent PET (T-100: manufactured by Toray), 125μ transparent P
ET (T-125: manufactured by Toray Co., Ltd.) as a substrate, a heat transfer sheet provided with the same receiving layer and a resin layer having a small heat shrinkage as described above, and three kinds of transparent PET similar to the above as comparative examples
Then, the same transfer as described above was performed using the heat transfer sheet provided with only the receiving layer in the same manner as described above, and the degree of curl was examined. The results are shown in Table 1.

Transfer conditions Transfer-type printer: VY-50 (manufactured by Hitachi, Ltd.) Printing energy 90 mj / mm ² One color high density solid printing Example 2, Comparative Example 2 The same heat-transfer sheet as in Example 1 (substrate thickness 75 μm,
On the back side of each of the resin layers having a small heat shrinkage of 100 μ and 125 μ), a 38 μm thick white PET (E-2) is further applied with an adhesive (S Dyne AE349: manufactured by Sekisui Chemical, thickness 3 μm).
0, manufactured by Toray Co., Ltd.) and three heat transfer sheets obtained by laminating white PET on the back surface of the base material of the three heat transfer sheets similar to Comparative Example 1. Using Comparative Example 2, transfer was performed under the same conditions as in Example 1, and the degree of curl was examined. The results are shown in Table 2.

Example 3, Comparative Example 3 Two kinds of vinyl chloride sheets (C-3033 and C-0436: manufactured by Mitsubishi Plastics) having a thickness of 150 μm and two kinds of vinyl chloride sheets (C-3033 and C-4020: 200 μm thick) On the back surface of the resin composition, the following ink composition for forming a resin layer having a small heat shrinkage was applied with a bar coater so as to be 3 g / m ² when dried with a bar coater, dried with a dryer, and then dried in an oven. At 50 ℃
For 5 minutes to obtain a heat-transferable sheet (the receptor layer is not provided because the substrate itself has a dye-receiving property).
The obtained four types of heat transfer sheets and the four types of heat transfer sheets as comparative examples which were not provided with a resin layer having a small heat shrinkage rate on the back surface of each of the above-mentioned base materials and were directly used as heat transfer sheets as comparative examples, respectively. Transfer was performed under the same conditions, and the degree of curl was examined. The results are shown in Table 3.

Ink composition for resin formation with low heat shrinkage ・ Acrylic resin (BR-85: manufactured by Mitsubishi Rayon) 10 parts ・ Solvent (toluene: ethyl acetate = 1: 1) 90 parts Example 4 and Comparative Example 4 The same heat-transferring sheet as in Example 3 and Comparative Example 3 was further coated with a pressure-sensitive adhesive to a thickness of 38 μm on the resin layer side having a small heat shrinkage.
Of white PET (E-20: manufactured by Toray Industries, Inc.) was laminated to form a heat transfer sheet. Using each of these heat transfer sheets, transfer was performed under the same conditions as in Example 1, and the degree of curl was examined. The results are shown in Table 4.

Example 5 and Comparative Example 5 An ink composition for forming a resin layer having a small heat shrinkage ratio having the following composition was applied to one surface of the same substrate as in Example 1 so as to be 5 g / m ² when dried with a bar coater. After drying in a dryer, the same ink composition for forming a receptor layer as in Example 1 was applied to the resin layer surface so as to be 5 g / m ² at the time of drying, dried in a dryer, and further dried in an oven. At 80 ° C in
After drying for 10 minutes, a receptor layer was formed to obtain a heat transfer sheet. Using these heat transfer sheets, transfer was performed under the same conditions as in Example 1, and the degree of curl was examined. The results are shown in Table 5. Table 5 also shows the results of Comparative Example 1 for comparison.

Ink composition for forming resin layer with low heat shrinkage ・ Polyurethane (Takelac E-360: manufactured by Takeda Pharmaceutical) 15 parts ・ Solvent (MEK: toluene = 1: 1) 85 parts [Effects of the Invention] As described above, the heat transfer sheet of the present invention is provided between the base material and the receiving layer and / or on the back side of the base material according to JIS-K-6732.
Because a resin layer with a small heat shrinkage of 100 ° C for 10 minutes, a resin with a heat shrinkage of -1.0 to 1.5% and a softening temperature of 90 ° C or more for 10 minutes is provided, heat is applied to the heat transfer sheet by transfer heat by a thermal head. There is no risk of curling,
No distortion or color shift occurs. As a result, the heat-transferred sheet in the transfer device has good paper-passing properties, can perform smooth transfer, and when used for creating an OHP original, obtains an OHP original with an excellent distortion-free projected image. It has effects such as being able to.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is a longitudinal sectional view of a heat transfer sheet of the present invention in which a resin layer having a small heat shrinkage ratio is provided on the back side of a base material. FIG. 3 is a longitudinal sectional view of a heat transfer sheet of the present invention in which a resin layer having a small heat shrinkage ratio is provided between the layers, and FIGS. 3 and 4 are longitudinal sectional views showing different embodiments of the heat transfer sheet of the present invention. is there. DESCRIPTION OF SYMBOLS 1 ... Heat transfer sheet, 2 ... Base material, 3 ... Reception layer 5 ... Resin layer with small heat shrinkage

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-112693 (JP, A) JP-A-61-144394 (JP, A) JP-A-62-198497 (JP, A) JP-A-2- 3395 (JP, A)

Claims (2)

(57) [Claims] 1. A receiving layer for receiving a dye migrating from a thermal transfer sheet, a substrate on which the receiving layer is carried, and between the receiving layer and the substrate and / or on the back side of the substrate. JI
The heat shrinkage at 100 ° C. for 10 minutes in S-K-6734 is −1.0
A resin layer having a heat shrinkage of at least 1.5% and a softening temperature of 90 ° C. or higher, and the resin layer is selected from polyacryl, polyurethane, polycarbonate, vinylidene chloride, polyamide, and polyester. A heat transfer sheet characterized by the following. 2. A method according to JIS-K-6734, wherein a back surface of a substrate having dye receptivity transferred from a thermal transfer sheet is coated with 100
℃, 10 min heat shrinkage -1.0 ~ 1.5% and softening temperature 90
A resin layer having a small heat shrinkage made of a resin having a temperature of not less than ° C is provided, and the resin layer is made of polyacryl, polyurethane, polycarbonate, vinylidene chloride, polyamide,
A heat transfer sheet characterized by being selected from polyester.