JPH10181229A - Manufacture of sheet to be transferred thermally - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet to be transferred thermally, which is low in price, has a high-grade impression, develops no printing curling and neither abnormal transferring nor omission of dot and has a favorable storage properties. SOLUTION: This is a manufacturing method of a sheet to be transferred thermally, used in combination with a heat transfer sheet bearing a dye transferable through thermal sublimation, evaporation or melting. A support is produced by extrusion-laminating a resin onto a base material. After that, by bringing a cooling roller, the surface of which is mirror-finished or embossed, into contact with the surface of the support under the condition that the temperature of the resin of the support is higher than Tg, a surface having the center-line mean roughness of 0.2-4.0μm Ra is formed on the support so as to carry the resin of a dye accepting layer on the surface of the support.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a sheet to be thermally transferred.

[0002]

2. Description of the Related Art Conventionally, in a heat transfer sheet used in a sublimation type thermal transfer system, a synthetic paper or a synthetic paper bonded to a natural paper is generally used as a support for supporting a dye-receiving layer resin. Have been. However, the heat transfer sheet obtained by using synthetic paper as a support has a low rigidity, and has a fluffy feel and lacks a sense of quality. In addition, there is a disadvantage that after printing an image, print curl occurs due to heat. In addition, if a material obtained by laminating synthetic paper with natural paper as a core material is used as a support, the above-mentioned disadvantages are solved,
The number of manufacturing steps increases, and the cost increases.

A heat transfer sheet which does not have the above-mentioned drawbacks, that is, is inexpensive, has a high quality feeling, and has no print curl, is disclosed in US Pat. No. 4,774,224 using a substrate obtained by extruding and laminating a resin on a substrate. There is a heat transfer sheet described in the gazette. This is because the surface roughness of the support obtained by coating the base material with the resin is 7.5 RaμimAA (about 0.019 μmRa) or less, so that the surface of the heat transfer sheet when the dye receiving layer resin layer is provided. Is smoothed, and the difference in gloss between a printed portion and a non-printed portion, which becomes smooth due to heat during printing, is eliminated, and partial gloss unevenness due to printing is eliminated.

However, when the smoothness of the surface of the support is very high as in the above-mentioned US Patent Publication, the adhesiveness with the resin of the receiving layer becomes weak, and the resin of the receiving layer peels off from the support. In some cases, the heat transfer sheet may be deteriorated in storage stability, or may be peeled off during printing and may be transferred to the heat transfer sheet (abnormal transfer). Conversely, when the surface of the support is very matte, the surface of the heat transfer sheet provided with the dye receiving layer also becomes very matte, and the adhesion with the heat transfer sheet at the time of printing is improved. As a result, defects such as missing dots occur in the printed image.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a heat-transferable sheet which is inexpensive, has a high-class feel, does not cause print curl, and has good storage stability without abnormal transfer and dot omission. is there.

[0006]

That is, the present invention includes the following inventions. (1) A method for producing a thermal transfer sheet used in combination with a thermal transfer sheet carrying a dye capable of sublimating, vaporizing, or dissolving and transferring by heat, wherein a support is formed by extruding and laminating a resin on a substrate. After the preparation, when the temperature of the resin is equal to or higher than Tg, a mirror surface or an embossed cooling roll is applied to the support surface to form a surface having a center line average roughness of 0.2 to 4.0 μmRa. And supporting the dye receiving layer resin on the surface of the support.

(2) A method for producing a heat transfer sheet used in combination with a heat transfer sheet carrying a dye capable of sublimating, vaporizing, or dissolving and transferring by heat, comprising extruding a resin onto a substrate and laminating the resin. After preparing the support, the surface of the roll heated to a temperature equal to or higher than the Tg of the resin is heat-pressed to the surface of the support using a mirror or embossed heating roll, so that the center line average roughness is 0.2 to
The method for producing a heat-transferable sheet, comprising forming a surface having a thickness of 4.0 μm Ra and supporting a dye-receiving layer resin on the surface of the support.

(3) When hot pressing the surface of the support,
(2) The method of (2) in which an elastic roll is applied to a surface opposite to a surface to which the heating roll contacts, to adjust the center line average roughness of the support surface. (4) The resin to be extruded and laminated on the base material contains an organic and / or inorganic filler (1) to (3).
the method of. (5) The method according to (4), wherein the inorganic filler is titanium oxide. (6) Anchor treatment is applied to the base material (1)-
The method of (5). (7) The method according to (1) to (6), wherein the dye-receiving layer resin has a Tg of 100 ° C. or less.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a substrate to which a resin is extruded and laminated on a substrate is used as a support for a sheet to be heat-transferred, and the surface roughness is adjusted to 0.2 to 4.0 .mu.mRa, thereby reducing the cost. The object of the present invention is to provide a heat-transferable sheet having a high-grade feel and excellent storage stability without print curl, abnormal transfer, and missing dots. Surface roughness in the present invention,
It is the center line average roughness (Ra) defined in JIS B 0601. In addition, dot omission of a printed image due to low smoothness of the surface of the heat transfer sheet occurs remarkably when a resin having a relatively high Tg such as polycarbonate is used as a resin for the dye receiving layer.

However, as a resin for the dye receiving layer, T
When a resin having a low g is used, specifically, a resin having a Tg of 100 ° C. or less, the resin is easily deformed by heat, and is superimposed on a thermal transfer sheet at the time of printing, and heated by a thermal head or the like. When pressed, the surface of the heat transfer sheet is plasticized by heat and pressed, and the adhesion between the heat transfer sheet and the heat transfer sheet increases. As a result, when a resin having a Tg of 100 ° C. or less is used as the resin for the dye receiving layer, the surface roughness of the dye receiving layer can be covered to some extent.

As the base material of the present invention, natural paper such as paperboard, medium quality paper, high quality paper, art paper, coated paper, cast coated paper, kraft paper, synthetic resin emulsion impregnated paper; polyolefin film such as polyethylene and polypropylene ;
Polyester films such as polyethylene terephthalate, polyethylene naphthalate, and polycarbonate; halogen-based films such as polyvinylidene chloride and polyvinylidene fluoride; polysulfone films; polyether films; polyamide films such as nylon and aromatic polyamide films; aromatic heterocycles such as polyimide films A polymer film; a polyxylylene film; an aluminum foil; a nonwoven fabric, synthetic paper, or the like having a heat resistance that does not cause deformation, decomposition, or the like when a heated resin is placed thereon is desirable.

These substrates may contain additives such as sizing agents, fixing agents, paper strength agents, fillers, antistatic agents, dyes, optical brighteners, antioxidants, and lubricants. It may be applied to the surface. In the present invention, as the resin to be laminated on the substrate, for example, when laminated by extrusion, as the extruded resin, high-density polyethylene,
Polyolefin resins such as medium density polyethylene, low density polyethylene, polypropylene, ethylene-vinyl acetate copolymer;
Polyester resins such as polyethylene terephthalate; ionomer resins; nylons; resins having a small neck-in and relatively good drawdown properties, such as polystyrene and polyurethane, are preferably used. The resin may be used alone or as a mixture of several types. The extruded resin is coated on one or both sides of the substrate. When coated on both sides, different resins may be used.

The extruded resin may contain organic and / or inorganic fillers. These organic fillers include resin powders such as benzoguanamine; nylon; and polycarbonate. As inorganic fillers, titanium oxide, zinc oxide,
Barium sulfate, magnesium carbonate, potassium carbonate, alumina, silica, kaolin, clay, silicone powder, graphite, carbon, etc. are used. In particular, when titanium oxide is added to the extruded resin on the side on which the dye receiving layer is formed, the whiteness of the surface becomes high. Is preferred. As the titanium oxide, anatase type titanium oxide and / or rutile type titanium oxide can be used.

The filler can be contained in the extruded resin in an amount of 3 to 60%, preferably 10 to 30%.
Extrusion resins include dyes, pigments, optical brighteners,
Additives such as antioxidants, antistatic agents, lubricants, ultraviolet absorbers, heat stabilizers and light stabilizers may be added. It is preferable that these additives have relatively high heat resistance and do not denature or decompose while extruded resin is being melted and coated. It is desirable that the support of the heat transfer sheet in the present invention is subjected to an anchor treatment for improving the adhesive strength between the substrate and the resin layer to be extruded and laminated.

As the anchor treatment, polyester resin, polyurethane resin, acrylic polyol resin,
Single or multi-layer coating by adding a vinyl chloride-vinyl acetate copolymer resin or the like alone or as a mixture, and adding a reactive curing agent such as polyisocyanate, and a titanate and / or silane coupling agent as needed. And ion irradiation treatments such as corona treatment and plasma treatment, radiation irradiation treatments such as ultraviolet and electron beam treatments, solvent treatments, and flame treatments. One or a combination of these processing methods may be used as the anchor processing.

As the resin for the dye receiving layer of the heat transfer sheet in the present invention, any resin can be used as long as it is conventionally used for the receiving layer of this type of heat transfer sheet. However, those having a relatively low Tg, specifically, a Tg of 100 ° C. or less and having acceptability for a dye are more preferred. Examples of the material of the dye-receiving layer resin that can be used in the present invention include the following synthetic resins (a) to (e) alone or in combination 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 highly polar bonds. Polycaprolactone, polystyrene, polyvinyl chloride, polyacrylonitrile, etc.

The dye-receiving layer may be formed of 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 case of copolymer of vinyl chloride and vinyl acetate only,
It may contain a vinyl alcohol component and a maleic acid component.

Further, the dye receiving layer may be made of a styrene resin other than the above 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, maleic anhydride, and vinyl chloride-acrylic acid monomers.

In the present invention, if necessary, an ultraviolet absorber may be added to the dye receiving layer. 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 amount of addition is 0.0 to 100 parts by weight of the resin constituting the dye receiving layer.
It is about 5 to 5 parts by weight.

The dye receiving layer may contain a release agent for the purpose of improving the releasability from the thermal transfer sheet, if necessary. 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 dye receiving layer. The release agent is not limited to the case where it is added to the receiving layer, and a release agent dissolved or dispersed in an appropriate solvent may be coated on the surface of the receiving layer and dried to form the release agent layer. 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 dye receiving layer or on the entire surface.However, when the release agent layer is provided on a part of the surface of the dye receiving layer, 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. In this case, recording by another recording method can be performed, and the sublimation transfer recording method and another recording method can be used together.

If necessary, an adhesion improving layer may be provided on the surface of the support for improving the adhesion to the dye-receiving layer resin. As the adhesion improving layer, any material can be used as long as it makes the adhesion between the support and the dye-receiving layer resin stronger. For example, a polyester resin, a polyurethane resin, an acrylic polyol resin, a vinyl chloride-vinyl acetate copolymer resin And the like are applied alone or as a mixture. Further, a reactive curing agent such as polyisocyanate may be added as needed. Further, titanate and silane coupling agents may be used. Further, two or more layers may be laminated as necessary.

Further, ion irradiation and electron beam irradiation may be performed for the same purpose. Before and / or after providing the adhesion improving layer, ion irradiation and electron beam irradiation may be performed. The surface roughness of the support in the present invention is 0.2 to 0.2.
It is 4.0 μm Ra. This is because the surface roughness of the support is 0.2
If it is smaller than μmRa, the adhesiveness to the dye-receiving layer resin is weakened, and the preservability of the heat-transferable sheet is deteriorated. Further, when printing is performed by overlapping with the thermal transfer sheet, the resin of the receiving layer peels off from the support and loses to the thermal transfer sheet due to the peeling force between the thermal transfer sheet and the dye receiving layer after printing. .

Further, if the surface roughness is 4.0 μm Ra or more, even if the dye receiving layer resin is softened during printing, the surface cannot be flattened by the printing pressure, and the adhesion between the heat transfer sheet and the thermal transfer sheet can be reduced. Is insufficient, causing defects such as missing dots. In the present invention, as a method of adjusting the surface roughness of the support and setting the specific range, for example, after extruding and laminating a resin, when the temperature of the extruded resin is equal to or higher than the Tg of the resin, the roll surface has a mirror surface or There is a method of applying an embossed cooling roll. By changing the mirror surface and embossed state of the roll surface, a support having a desired surface roughness can be obtained.

As another method, there is a method in which the surface of the support is heat-pressed using a heated roll having a mirror surface or an embossed roll surface. In this case, the temperature of the heating roll is adjusted to be equal to or higher than the Tg of the extruded resin and within a range where the extruded resin is not thermally fused. When an elastic roll is applied to the surface of the support opposite to the surface to which the heating roll contacts, the effect of adjusting the surface roughness is high. As a method for adjusting the surface roughness of the support, a hot press plate is applied, sandpaper is applied, and the like, but the method is not particularly limited.

[0026]

Example 1 PHO manufactured by Fuji Photo Film Co., Ltd.
After subjecting this substrate to corona treatment using white (157 g / m ² ), an extruded resin consisting of 100 parts of low-density polyethylene and 15 parts of anatase-type titanium oxide was coated on the surface on the side provided with the dye-receiving layer. Extrusion coating was performed to a thickness of 30 μm. Also, on the back, low-density polyethylene 10
An extruded resin consisting of 0 parts and 5 parts of an antistatic agent was extrusion-coated. Thereafter, cooling was performed immediately using a solid gravure roll to obtain a support having a center line average roughness of 0.5 Ra μm. On the upper surface of the support, an ink composition for a receiving layer having the following composition was applied using a wire bar so that the coating amount at the time of drying was 6.0 g / cm ^3, and dried at 120 ° C. for 10 minutes. A thermal transfer sheet was obtained.

Ink composition for receptor layer 11.5 parts Polyester resin (Toyobo: Vylon 200) Vinyl chloride-vinyl acetate copolymer 5.0 parts (UCC: VYHH) Amino-modified silicone 1.2 parts (Shin-Etsu Chemical Industrial: KF-393) Epoxy-modified silicone 1.2 parts (Shin-Etsu Chemical: X-22-343) Methyl ethyl ketone 50 parts Toern 50 parts

Comparative Example 1 A support was obtained by using a mirror-finished roll as the cooling roll in Example 1. A calendering process is performed so that a mirror surface roll having a roll surface temperature of 65 ° C. is applied to the surface of the support on which the dye receiving layer is provided, and an elastic roll is applied to the opposite surface, so that the surface having a center line average roughness of 0.08 μm is formed. A support was obtained. A dye receiving layer was formed on this surface in the same manner as in Example 1, and Comparative Example 1 was obtained.

Example 2 Corona treatment was carried out using the same paper as in Example 1 as a substrate for a support, and then 100 parts of high-density polyethylene, 12 parts of anatase-type titanium oxide, and 0.1 parts of a fluorescent whitening agent were placed on the substrate. The extruded resin composed of the parts was extrusion-coated so as to have a thickness of 25 μm. An extruded resin composed of 100 parts of high-density polyethylene, 10 parts of silicone powder (Tospearl 130, manufactured by Toshiba Silicone Co., Ltd.), and 0.5 part of phosphate ester was extrusion coated on the back surface of the substrate. This support was cooled using a solid gravure roll in the same manner as in Example 1 to obtain a support having a center line average roughness of 1.0 Ra μm. A dye receiving layer was provided on the surface of the support in the same manner as in Example 1.

Comparative Example 2 The support of the heat transfer sheet obtained in the same manner as in Example 2 was left standing at 30 ° C. and 95% RH for 24 hours and humidified.
Apply 100μm PET film on both sides of this support,
The paper was calendered at a linear pressure of 200 kg / cm so that the mirror roll having a surface temperature of 70 ° C. was in contact with the dye receiving layer side and the backside was in contact with the elastic roll. The surface roughness of the dye receiving layer surface of the obtained support was 0.05 μm Ra. A dye receiving layer was provided on the surface of the support in the same manner as in Example 1.

Comparative Example 3 Extrusion coating was performed on the same substrate as in Example 1 using the same extruded resin, and cooling was performed using an embossing roll to obtain a support having a surface roughness of 10.0 μmRa. A dye receiving layer was provided on the surface of the support in the same manner as in Example 1.

COMPARATIVE EXAMPLE 4 Extrusion coating was performed in the same manner as in Example 2, and cooling was performed using an embossing roll to obtain a surface roughness of 12.0.
A μm support was obtained. A dye receiving layer was provided on the surface of the support in the same manner as in Example 1. The heat transfer sheets obtained in Examples 1 and 2 and Comparative Examples 1 and 2 were cut in a grid in accordance with JIS K5400, and further adhered to a commercially available cellophane tape, peeled off, and separated from the dye receiving layer and the support. The adhesion was tested. Table 1 shows the results. Printing was performed by combining the heat transfer sheets obtained in Examples 1 and 2 and Comparative Examples 3 and 4 with the heat transfer sheets obtained by the following method.
I saw missing dots on the surface. Table 2 shows the results.

(Preparation of Thermal Transfer Sheet) A 4.5 μm thick polyethylene terephthalate film (manufactured by Toray; Lumirror 5A-F-) was used to prepare a heat-resistant lubricating layer ink composition having the following composition.
53) A heat-resistant lubricating layer was formed by applying a wire bar and drying with hot air.

Ink composition for heat-resistant lubricating layer Polyvinyl butyral resin (manufactured by Sekisui Chemical, Esrec BX-1) 4.5 parts Toluene 45 parts Methyl ethyl ketone 45.5 parts Phosphate ester (manufactured by Dai-ichi Kogyo Seiyaku, Plysurf A-208S) 0.45 parts Diisocyanate “Lichenate D-110N” 75% ethyl acetate solution 2 parts The above film was cured by heating in an oven at 60 ° C. for 12 hours. The amount of ink applied after drying is about 1.2 g / m ²
Met. Next, on the surface of the film opposite to the heat-resistant lubricating layer, a dye layer composition having the following composition was applied so that the coating amount when dried was 1.0 g / cm ^3, and dried at 80 ° C. for 5 minutes. Thus, a thermal transfer sheet was obtained.

Ink composition disperse dye for dye layer (Kayaset Blue 714, manufactured by Nippon Kayaku Co., Ltd.) 4.0 parts Polyvinyl butyral resin (ESREC BX-1, manufactured by Sekisui Chemical) 4.3 parts Methyl ethyl ketone / toluene ( (Weight ratio 1/1) 80.0 parts (thermal transfer recording) A commercially available color video printer (Hitachi: V
Y-100).

[0036]

[Table 1]

[0037]

[Table 2]

The center line average roughness Ra in the present invention is measured by a surface shape measuring device Dektak 3030 (manufactured by Nippon Vacuum Engineering Co., Ltd.).
It measured using.

[0039]

According to the present invention, inexpensive and luxurious,
A heat-transferable sheet having good storability without print curl, abnormal transfer and missing dots can be obtained.

Claims (7)

[Claims] 1. A method for producing a heat-transferable sheet used in combination with a thermal transfer sheet carrying a dye capable of sublimation, vaporization, or dissolution and transfer by heat, wherein the resin is extruded onto a substrate and supported by lamination. After preparing the body, when the temperature of the resin is equal to or higher than Tg, a center roll average roughness is 0.2 to 4.0 μm by applying a mirror or embossed cooling roll to the support surface.
The method for producing a heat-receiving sheet, comprising forming a surface of Ra and supporting a dye-receiving layer resin on the surface of the support. 2. A method for producing a heat transfer sheet used in combination with a heat transfer sheet carrying a dye capable of sublimation, vaporization, or dissolution and transfer by heat, wherein the resin is extruded on a substrate and supported by lamination. After forming the body, the surface of the roll heated to a temperature equal to or higher than the Tg of the resin is heat-pressed to the surface of the support using a mirror or embossed heating roll, so that the center line average roughness is 0.2 to 4 mm. .
The method for producing a heat-transferable sheet, comprising forming a surface having a thickness of 0 μmRa and supporting a dye-receiving layer resin on the surface of the support. 3. The method according to claim 2, wherein, when the surface of the support is heated and pressed, an elastic roll is applied to a surface opposite to a surface to which the heating roll contacts to adjust the center line average roughness of the surface of the support. . 4. The method according to claim 1, wherein the resin to be extruded and laminated on the substrate contains an organic and / or inorganic filler. 5. The method according to claim 4, wherein the inorganic filler is titanium oxide. 6. The method according to claim 1, wherein the substrate has been subjected to an anchor treatment. 7. The method according to claim 1, wherein the resin of the dye receiving layer has a Tg of 100 ° C. or less.