JPH0699672A - Thermal transfer sheet - Google Patents

Abstract

PURPOSE:To produce a thermal transfer sheet by the method wherein the favorable surface, by which printing wrinkle developing by the difference between the sliding frictional coefficient of printed part and of non-printed part due to the lowering of the lubricity of image portion by the heat applied for transferring during transferring process is prevented from developing, is realized. CONSTITUTION:The thermal transfer sheet is prepared by forming a thermally transferable coloring material layer 3 on one side of base film 2, the other side of which includes a heat resistant lubricant layer 1, which contains fine fluoroplastic powder and silicone oil reactable with the binder resin of the ink therefor.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a thermal transfer sheet,
More specifically, the present invention relates to a thermal transfer sheet which is composed of a heat resistant slipping layer containing a specific composition and has no sticking phenomenon and has improved running property and contamination of a thermal head.

[0002]

2. Description of the Related Art A conventional thermal transfer sheet is a sublimation type thermal transfer sheet in which a dye layer composed of a sublimable dye and a binder is provided on one surface of a polyester film or the like. There is a heat-melting type heat transfer sheet provided with an ink layer composed of the composition. These thermal transfer sheets are heated from the backside thereof in an image form by a thermal head to transfer the ink layer to the transfer material to form an image.

Further, in the conventional thermal transfer sheet, when the material is used at a temperature higher than the melting point of the base polymer of the plastic film used as the base film,
During printing, problems such as fusion with the thermal head and deterioration of the thermal head's peeling and slippage, and breakage of the base film may occur. In order to solve such a problem, it has been proposed to apply a heat resistant slipping layer containing a surfactant, a wax, a silicone oil, and an inorganic or organic fine powder on the surface of the base film opposite to the ink layer. ing.

[0004]

A heat resistant slipping layer containing silicone oil (Japanese Patent Laid-Open No. 63-20336).
Has excellent slipperiness, but when the printed part and the non-printed part are on the same line (for example, a checkerboard pattern), there is a problem that slippage occurs between them and wrinkles occur. there were. In addition, the heat resistant slipping layer to which an inorganic or organic fine powder is added has a small contact area with the thermal head, and the phenomenon that the thermal head sticks during printing can be prevented, but wrinkles occur due to poor lubricity. There was a problem that caused it. There is also a method of adding finely divided fluororesin powder (Japanese Patent Laid-Open No. 62-169687), but unless the finely divided fluororesin powder is projected on the surface, the slidability cannot be exhibited and fine particles of The choice of dispersion method and dispersant is limited,
There was a problem of lacking stability as a product.

Further, a method of combining silicone oil and inorganic or organic fine powder can be considered, but in the combination of silicone oil and inorganic fine powder and the combination of silicone oil and organic fine powder, the above-mentioned printing portion and non-printing portion are When they were on the same line, it was not possible to prevent wrinkles due to the difference in the slip / friction coefficient between the patterns.

[0006]

In order to achieve the above object, in the thermal transfer sheet of the present invention, a thermal transferable color material layer is formed on one surface of a base material sheet, and silicone oil and fluorine are formed on the other surface. The wrinkle problem is solved by forming a heat resistant slipping layer made of a surfactant, which is optionally added to a resin binder containing a fine powder of a base resin.

[0007]

Since the heat resistant slipping layer of the present invention is composed of a film containing silicone oil and fluororesin fine powder, there is no difference between the coefficient of dynamic friction and the coefficient of static friction. There is no bleed out of silicone oils that are configured to react with the component resins.

Next, the constituent elements will be described in more detail. The silicone oil required in the present invention is a dimethylpolysiloxane compound. More preferably, it has a reactive group such as a hydroxyl group, an amino group, an epoxy group, an isocyanate group, a carboxyl group, a mercapto group, an acryl group and a methacryl group. It is desirable to select a variety that reacts with these reactive groups and the components of the binder constituting the heat resistant slipping layer. The one that reacts with the binder resin does not bleed out under some conditions like mere silicone oil.

The amount of silicone oil added is 1 to 100 parts by weight with respect to 100 parts by weight of the binder resin.
It is preferably 2 to 50 parts by weight. When the amount of silicone oil added is small, sufficient lubricity cannot be obtained, which causes print wrinkles. When the amount of silicone oil added is too large, the dye of the corresponding heat transferable coloring material layer is stored when the heat transfer sheet is stored by winding. Shifts to the heat resistant slipping layer, and sufficient slipperiness is not obtained, which causes print wrinkles. Further, an antistatic agent such as a surfactant or a conductive agent such as carbon black may be added in order to impart an antistatic property to the obtained thermal transfer sheet.

The silicone oil chemically reacted with the components of the binder does not bleed out and has the property of not settling onto the non-coated surface. That is, the production of the thermal transfer sheet
(1) Application of heat resistant slipping layer (2) When taking the step of printing the heat transferable color material layer, the silicone oil contained in the heat resistant slipping layer of the first step does not migrate to the non-coated surface, It has a function of preventing the adhesion of the heat transferable color material layer from being hindered.

Fluorine resin fine powder is polyfluorinated octyl methacrylic acid ester, polyhexafluoropropylene,
Polytetrafluoroethylene, polytrifluoroethylene, fluoroacrylic resin, polyvinylidene fluoride, polyvinyl fluoride, polytrifluoride-ethylene chloride and the like are available, but polytetrafluoroethylene is preferable. The desirable particle size of the fluororesin fine powder is 0.1 to 10 μm, more preferably 0.5.
~ 5 μm. The addition amount thereof is 1 to 50 parts by weight, and the more desirable addition amount is 1 to 20 parts by weight, based on 100 parts by weight of the resin in the binder. If the amount is less than 1 part by weight, sufficient lubricity cannot be obtained, which may cause wrinkles in the print. If the amount is more than 50 parts by weight, the desired energy is retained because it remains as dust on the thermal head and is accumulated. It is not transferred accurately from the head to the thermal transfer sheet,
A good image cannot be obtained.

As the binder resin, a thermosetting resin, an ionizing radiation curable resin or the like can be applied as long as it has a film-forming property, but a thermoplastic resin or a cross-linked product thereof is preferable.
As the thermoplastic resin, for example, polyester resin,
Polyacrylic ester resin, polyvinyl acetate resin, styrene acrylate resin, polyurethane resin, polystyrene resin, polyvinyl chloride resin, polyether resin, polyamide resin, polycarbonate resin, polyethylene resin, polypropylene Resin,
Thermoplastic resins such as polyacrylate resins, polyacrylamide resins, polyvinyl chloride / vinyl acetate copolymer derivatives, polyvinyl butyral resins, and polyvinyl acetoacetal resins are used, and polyvinyl butyral resins and polyvinyl acetoacetal resins are particularly preferable.

In a preferred embodiment of the present invention, the slipping layer preferably uses a binder containing a polyisocyanate as a cross-linking agent, which imparts heat resistance, coating strength and adhesion to a base film. These polyisocyanates may be the conventionally known paints, adhesives or the polyisocyanates used in the synthesis of polyurethanes. These polyisocyanate compounds are trade names such as Takenate (manufactured by Takeda Pharmaceutical Co., Ltd.), Barnock (manufactured by Dainippon Ink and Chemicals), Coronate (manufactured by Nippon Polyurethane), Duranate (manufactured by Asahi Kasei Kogyo), and Dismodur (manufactured by Bayer). It can be obtained and used in the present invention. The addition amount of polyisocyanate is the same as that of the binder resin 1 that constitutes the slipping layer.
A suitable range is 5 to 200 parts by weight with respect to 00 parts by weight. The -NCO / -OH ratio is preferably in the range of 0.8 to 2.0. When the amount of polyisocyanate used is insufficient,
Since the crosslink density is low, the heat resistance is insufficient. On the other hand, when the crosslink density is too large, the shrinkage of the coating film formed cannot be controlled, the curing time is prolonged, and unreacted -NCO groups remain in the slipping layer. May act negatively, such as reacting with moisture in the atmosphere.

To form the heat resistant slipping layer, an acetone selected from the above binder materials to suit the coating suitability,
A coating solution is prepared by dissolving or dispersing it in a solvent such as methyl ethyl ketone, toluene, or xylene, and the coating solution is applied, dried, and solidified by a conventional coating means such as a gravure coater, a roll coater, and a wire bar. It is formed. The thickness of the coating amount, or heat-resistant lubricating layer is also an important factor, often 3.0 g / m ² or less on a solids basis in the present invention, preferably the thickness of 0.1 to 1.0 g / m ² A heat resistant slipping layer having sufficient performance can be formed. Incidentally, in the present invention, after the heat resistant slipping layer is applied and dried, unreacted isocyanate groups often remain in the layer, so it is preferable to carry out a heating / aging treatment for completing the reaction. . It is also effective to provide a primer layer prior to forming the heat resistant slipping layer.

The substrate film of the present invention can be used if it has conventionally known heat resistance and strength. For example, paper having a thickness of 0.5 to 50 μm, preferably 3 to 10 μm, The processed paper, polyester film, 1,
4-polycyclohexylene dimethylene terephthalate film, polyethylene naphthalate film, polyphenylene sulfide film, polystyrene film,
Polypropylene film, polysulfone film, aramid film, polycarbonate film, polyvinyl alcohol film, cellophane, etc. are particularly preferable, and polyethylene terephthalate film (polyester film) is particularly preferable. It is also preferable to form an adhesive layer (primer layer) on one side or both sides of the film, if necessary. These base films may be single films or continuous films supplied by winding,
The material can be selected according to the application.

In the case of a sublimation type heat transfer sheet, a layer containing a sublimation dye is formed as the heat transferable color material layer formed on one surface of the substrate film of the present invention, and a heat melting type heat transfer sheet. In the case of 1, the layer is formed with a hot-melt ink colored with a pigment or the like. The sublimation type thermal transfer sheet will be described in detail below as a representative example, but the present invention is not limited to the sublimation type thermal transfer sheet. As the dye of the heat transferable color material layer, any dye used in a conventionally known heat transfer sheet is effective for the present invention and is not particularly limited. For example, as the red dye, MSRed G, Macrolex Red
Violet R, Ceres Red7B, Sam
aron Red HBSL, Resolin Red
F3BS etc. are mentioned. Examples of yellow dyes include Holon Brilliant Yellow 6GL, PTY-52, Macrolex Yellow 6G and the like. Also, as the blue dye, Kayaset Blue 714, Waxolin Blue AP-
FW, Holon Brilliant Blue SR, MS Blue 1
00 etc. are mentioned.

The binder resin constituting the heat transferable color material layer includes fibrin derivatives such as ethyl cellulose, hydroxyethyl cellulose, ethyl hydroxy cellulose, hydroxypropyl cellulose, methyl cellulose, cellulose acetate, cellulose acetate butyrate, polyvinyl alcohol, polyvinyl acetate, Examples include polyvinyl butyral, polyvinyl acetal, vinyl-based resins such as polyvinylpyrrolidone, acrylic resins such as poly (meth) acrylate and poly (meth) acrylamide, polyurethane-based resins, polyamide-based resins and polyester-based resins.
Of these, cellulose derivatives, vinyl resins, acrylic resins, urethane resins, and polyester resins are preferable from the viewpoint of heat resistance, dye migration, and the like.

The heat-transferable color material layer is dissolved on one surface of the above-mentioned substrate film by adding an appropriate additive such as a releasing agent to the dye and binder as described above and a suitable solvent. It is dispersed, and the ink is applied and dried by, for example, a gravure printing method, a screen printing method, and a reverse roll coating method using a gravure plate to form the ink.
The thermal transferable color material layer thus formed has a thickness of 0.2 to 5.
0 μm, preferably 0.4-2.0 μm thick,
Further, the sublimable dye in the heat transferable color material layer is contained in the layer of 5 to 9 in the layer.
0% by weight, preferably 10 to 70% by weight is preferred. When the image of the desired heat transferable color material layer is mono-color, one kind is selected from the dyes described above, and when it is a full-color image, suitable cyan, magenta and yellow (as necessary, Add black and select) to form.

The image-receiving sheet used for forming an image by using the above-mentioned thermal transfer sheet may be any one as long as its recording surface has dye-accepting property to the dye, and In the case of paper, metal, glass, synthetic resin or the like having no property, a dye receiving layer may be provided on at least one surface. In the case of a heat-melting type heat transfer sheet, the material to be transferred is not particularly limited, and may be ordinary paper or plastic film. The thermal transfer performed using the above thermal transfer sheet and image receiving sheet is not particularly limited as a known thermal transfer printer can be used as it is.

[0020]

EXAMPLES Next, the present invention will be described more specifically with reference to Examples and Comparative Examples. (Example 1) Ink for heat resistant slipping layer A Polyvinyl butyral resin (S-REC BX-1 manufactured by Sekisui Chemical Co., Ltd.) 3.60 parts Polyisocyanate (manufactured by Barnock D750 Dainippon Ink) 8.40 parts Modified silicone oil (Paintad M Dow Corning) 2.40 parts Tetrafluoroethylene resin fine powder (Fluon L170J manufactured by Asahi Glass Co., Ltd.) 0.60 parts Toluene 85.0 parts Methyl ethyl ketone 85.0 parts Polyester film (4. (5 μm, made of diamond foil), using Miyabar # 5 on one side to apply it to a thickness of 1.0 μm when dried, dried, and cured by heating and aging in an oven at 60 ° C. for 2 days. Then, a heat resistant slipping layer was formed. Next, the following thermal transferable color material layer forming ink was gravure-printed on the surface opposite to the heat resistant slipping layer so that the thickness when dried was 1.0 μm, to obtain a thermal transfer sheet of the present invention. Ink for forming heat transferable color material layer C. I Solvent Blue 22 5.50 parts Acetacetal resin 3.00 parts Methyl ethyl ketone 22.54 parts Toluene 68.18 parts

Example 2 The heat transfer of the present invention was carried out in the same manner as in Example 1 except that the ink B for heat resistant slipping layer described below was used instead of the ink A for heat resistant slipping layer in Example 1. Got the sheet. Ink for heat resistant slipping layer B Polyvinyl butyral resin (S-REC BX-1 Sekisui Chemical Co., Ltd.) 3.60 parts Polyisocyanate (Bernock D750 manufactured by Dainippon Ink) 8.40 parts Modified silicone oil (KF96 Shin-Etsu Chemical Co., Ltd.) 2.40 parts Tetrafluoride ethylene resin fine powder (Lubron L-2 manufactured by Daikin Industries) 0.60 parts Toluene 85.00 parts Methyl ethyl ketone 85,000 parts

Example 3 The heat transfer of the present invention was carried out in the same manner as in Example 1 except that the ink C for heat resistant slipping layer described below was used instead of the ink A for heat resistant slipping layer in Example 1. Got the sheet. Ink for heat resistant slipping layer C Polyvinyl butyral resin (S-REC BX-1 manufactured by Sekisui Chemical Co., Ltd.) 3.60 parts Polyisocyanate (Bernock D750 manufactured by Dainippon Ink) 8.40 parts Modified silicone oil (SF8417 Toray Silicone) 2.40 parts Tetrafluoride ethylene resin fine powder (TLP-10F manufactured by Mitsui DuPont Fluorochemicals) 0.60 parts Toluene 85.00 parts Methyl ethyl ketone 85.00 parts

(Comparative Example 1) A heat transfer sheet currently on the market is used in the same manner as in Example 1 except that the ink for heat resistant slipping layer is replaced with the ink for heat resistant slipping layer in Example 1. Got Ink for heat resistant slipping layer Polyvinyl butyral resin (S-REC BX-1 manufactured by Sekisui Chemical) 3.60 parts Polyisocyanate (manufactured by Barnock D750 Dainippon Ink) 8.40 parts Phosphate ester surfactant (Phosphanol RD720 manufactured by Toho Chemical) 2 40 parts Talc (Microace L-1 made by Nippon Talc) 0.60 parts Toluene 85.00 parts Methyl ethyl ketone 85.00 parts

Comparative Example 2 In place of the heat resistant slipping layer ink A used in Example 1, a heat resistant slipping layer ink containing only silicone oil as a lubricant was used, and otherwise the same as in Example 1. As a result, a thermal transfer sheet as a comparative product of the present invention was obtained. Ink for heat resistant slipping layer Polyvinyl butyral resin (S-REC BX-1 Sekisui Chemical Co., Ltd.) 3.60 parts Polyisocyanate (Bernock D750 manufactured by Dainippon Ink) 8.40 parts Modified silicone oil (Painted M Dow Corning) 2.40 parts Toluene 85.00 parts Methyl ethyl ketone 85.00 parts

Comparative Example 3 A heat resistant slipping layer ink containing silicone oil and talc was used in place of the heat resistant slipping layer ink A used in Example 1, and the same procedure as in Example 1 was repeated. A thermal transfer sheet as a comparative product of the invention was obtained. Ink for heat resistant slipping layer Polyvinyl butyral resin (S-REC BX-1 made by Sekisui Chemical Co., Ltd.) 3.60 parts Polyisocyanate (Bernock D750 made by Dainippon Ink) 8.40 parts Modified silicone oil (made by Painted M Dow Corning) 2.40 parts Talc (Microace L-1 made by Nippon Talc) 0.60 parts Toluene 85.00 parts Methyl ethyl ketone 85.00 parts

(Comparative Example 4) Ink for heat resistant slipping layer containing a surfactant and fluororesin fine powder was used in place of the ink A for heat resistant slippery layer in Example 1, and the same as Example 1 except for the above. Similarly, a thermal transfer sheet which was a comparative product of the present invention was obtained. Ink for heat resistant slipping layer Polyvinyl butyral resin (S-REC BX-1 manufactured by Sekisui Chemical) 3.60 parts Polyisocyanate (manufactured by Barnock D750 Dainippon Ink) 8.40 parts Phosphate ester surfactant (Phosphanol RD720 manufactured by Toho Chemical) 2 40 parts Tetrafluoroethylene resin fine powder (Fluon L170J manufactured by Asahi Glass Co., Ltd.) 0.60 parts Toluene 85.00 parts Methyl ethyl ketone 85.00 parts

(Evaluation Method) The above-mentioned thermal transfer sheet is overlaid on a conventional image-receiving paper, and a solid pattern is printed by a commercially available video printer to visually determine the occurrence of wrinkles. For the friction coefficient, the sliding friction coefficient with respect to the thermal head was measured according to ASTM D1894. The results of this evaluation are shown in Table 1.

[0028]

[Table 1] Transfer condition: pulse width ···· 16msec Feeding speed ···· 33.3msec / line Applied voltage ··· 12V However, the dynamic friction coefficient during printing was measured.

[0029]

In the thermal transfer sheet of the present invention, the heat resistant slipping layer is composed of a film containing fine particles of silicone oil and fluororesin, and there is no difference between the coefficient of dynamic friction and the coefficient of static friction. Driving is stable and wrinkles can be prevented. In addition, since the silicone oil is configured to react with the resin of the binder component of the ink for heat resistant slipping layer, there are problems such as bleed-out that is observed in ordinary silicone oil and adhesion failure of the thermal transfer sheet due to migration. It is possible to produce a thermal transfer sheet having a good heat resistant slipping layer.

[Brief description of drawings]

FIG. 1 is a sectional view of a thermal transfer sheet of the present invention.

[Explanation of symbols]

 1 Heat Resistant Sliding Layer 2 Base Film 3 Heat Transferable Color Material Layer

Claims (2)

[Claims] 1. A thermal transfer sheet comprising a substrate film and a heat transferable color material layer formed on one surface of the substrate film, and a heat resistant slipping layer formed on the other surface of the base film, wherein the heat resistant slipping layer comprises silicone oil and fluororesin. A thermal transfer sheet comprising a resin binder containing fine powder. 2. The thermal transfer sheet according to claim 1, wherein the silicone oil has reactivity.