JP2008087290A - Film for protective layer transfer sheet and protective layer transfer sheet using the film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a protective layer transfer sheet which is excellent in peeling properties between a substrate and a peeling layer and can be produced at low costs, and a film for the protective layer transfer sheet. <P>SOLUTION: The film for the protective layer transfer sheet has the substrate, a heat resistant sliding layer which is formed on the substrate and contains an isocyanate compound and a hydroxy group-containing resin, and the peeling layer which is formed on a surface of the substrate opposite to the surface whereon the heat resistant sliding layer is formed and contains a transparent resin material. The transparent resin material does not substantially have a functional group having an active hydrogen atom. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a protective layer transfer sheet used for forming a protective layer for protecting an image printed by a sublimation type thermal transfer system, and a protective layer transfer sheet film used therefor.

  Conventionally, an image forming method using a thermal transfer method is known as one of color or monochrome image forming techniques, and has been widely used as a means for easily obtaining a high-quality image. The thermal transfer system is a method of forming an image by transferring a thermal transfer sheet having a dye exhibiting specific thermal properties from a thermal transfer sheet to a thermal transfer image receiving sheet using a thermal printing unit such as a thermal head or a laser. Such a thermal transfer system has the advantage that the apparatus can be miniaturized and is low in cost.

  In general, the thermal transfer system is roughly classified into two types, a thermal melting transfer system and a thermal diffusion transfer system (sublimation type thermal transfer system), depending on a dye transfer mechanism from the thermal transfer sheet to the thermal transfer image receiving sheet. The thermal melt transfer system is a system in which an image is formed by using a thermal transfer sheet having a hot melt dye and transferring the hot melt dye to a thermal transfer image receiving sheet by a heat transfer process. On the other hand, the thermal diffusion transfer system (sublimation thermal transfer system) is a thermal transfer sheet having a thermal diffusible dye (sublimation dye), and the thermal diffusive dye (sublimation dye) is transferred to the thermal diffusion transfer mechanism ( In this method, images are transferred to a thermal transfer image receiving sheet by a sublimation transfer mechanism. The latter thermal diffusion transfer method (sublimation type thermal transfer method) can arbitrarily adjust the amount of thermal diffusible dye transferred to the thermal transfer image-receiving sheet by controlling the degree of heating of the thermal transfer sheet. It is possible to form a high-gradation image with excellent reproducibility, which is advantageous for full-color image formation. Because of these advantages, thermal diffusion transfer-type thermal transfer technology is widely used in business photographs, personal computer printers, video printers, and the like.

  In addition, a protective layer is usually formed on the surface of an image printed by the sublimation thermal transfer method for the purpose of improving the durability of the image and enabling long-term storage. Such a protective layer is obtained by using a protective layer transfer sheet having a release layer formed on a substrate, printing an image on the image receiving sheet, and then thermally transferring the release layer to the entire printing area of the image receiving sheet. Is formed.

  Here, as illustrated in FIG. 3, the general configuration of the protective layer transfer sheet 100 includes a release layer 102 formed on a substrate 101, and a release layer 102 formed on the release layer 102. A heat seal layer 103 that is heat-sealed on the thermal transfer image receiving sheet, and further formed on the surface of the substrate 101 opposite to the surface on which the release layer 102 is formed. It is known to have a heat-resistant slipping layer 104 that prevents the substrate 101 from being thermally damaged when thermally transferred onto the substrate 101. As the protective layer transfer sheet having such a configuration, an isocyanate compound is generally contained in the heat-resistant slipping layer, and an acrylic resin is used for the release layer. For example, Patent Document 1 and It is disclosed in Patent Document 2.

By the way, the protective layer transfer sheet having the above-mentioned structure is usually formed by a roll-to-roll process on which a heat-resistant slipping layer is formed on a long base material and wound up into a roll shape. It is manufactured by laminating a release layer and a heat seal layer on the substrate while unwinding the substrate from the roll. This is because according to such a manufacturing method, the protective layer transfer sheet can be continuously manufactured with high productivity.
However, when a protective layer transfer sheet having the above-described configuration is formed by such a method, there is a problem that the peelability between the release layer and the substrate is impaired, and such an industrial production process has such a problem. It has been pointed out that it is not desirable to use the method.

In response to such problems, Patent Document 3 discloses a method of forming a release layer between the substrate and the release layer to improve the problem of the peelability. Such a method has the advantage that the above-described problem of peelability can be improved and a protective layer transfer sheet can be produced with high productivity. However, in such a method, it is necessary to add a new layer called a release layer, so that there are new problems that the manufacturing cost increases and the quality design becomes difficult.
For these reasons, conventionally, it has been difficult to produce a protective layer transfer sheet excellent in peelability between the substrate and the release layer at a low cost.

JP-A-4-35988 Japanese Patent Laid-Open No. 4-142988 Japanese Patent Laid-Open No. 11-277899

  The present invention has been made in view of such a situation, and is a protective layer transfer sheet that is excellent in releasability between a substrate and a release layer and can be produced at low cost, and a protective layer used in the protective layer transfer sheet The main object is to provide a transfer sheet film.

  In order to solve the above problems, the present invention provides a base material, a heat-resistant slip layer formed on the base material and containing an isocyanate compound and a hydroxyl group-containing resin, and the heat-resistant slip layer of the base material. A protective layer transfer sheet film having a release layer containing a transparent resin material formed on a surface opposite to the coated surface, wherein the transparent resin material substantially has a functional group having active hydrogen. A protective layer transfer sheet film is provided.

According to the present invention, for example, the transparent resin material contained in the release layer is substantially free of a functional group having an active hydrogen having reactivity with the isocyanate compound. Even when the protective layer transfer sheet film of the invention is produced by a Roll to Roll process, it is possible to prevent the peelability between the substrate and the release layer from being impaired.
Further, according to the present invention, as the transparent resin material, a material having substantially no functional group having an active hydrogen having reactivity with the isocyanate compound is used, so that a release layer or the like as in the prior art is used. The film for protective layer transfer sheets excellent in the peelability of the said base material and the said peeling layer can be obtained, without adding new structure of these.
Therefore, according to the protective layer transfer sheet film of the present invention, it is possible to obtain a protective layer transfer sheet that is excellent in releasability between the substrate and the release layer and can be produced at low cost.

  In this invention, it is preferable that the said transparent resin material contains 1st transparent resin whose Tg is 90 degreeC or more. By including such a first transparent resin, it is possible to obtain a protective layer transfer sheet having further excellent releasability between the substrate and the release layer, using the protective layer transfer sheet film of the present invention. Because it becomes possible.

  Moreover, in this invention, it is preferable that the said transparent resin material contains the said 1st transparent resin and 2nd transparent resin whose Tg exists in the range of 40 to 80 degreeC. As a result, the protective layer transfer sheet produced using the protective layer transfer sheet film of the present invention has excellent peelability between the substrate and the release layer at the time of thermal transfer, and the substrate at room temperature. It is because it can make it excellent in adhesiveness with the said peeling layer.

  Furthermore, in this invention, it is preferable that content of the said 1st transparent resin in the said transparent resin material is 60 mass% or more. This is because the protective layer formed by transferring the release layer onto the thermal transfer image-receiving sheet can have excellent plasticizer resistance.

  Furthermore, in the present invention, the first transparent resin is preferably polymethyl methacrylate (PMMA). Since polymethyl methacrylate (PMMA) is excellent in plasticizer resistance, a protective layer formed by transferring the release layer onto a thermal transfer image-receiving sheet by using such polymethyl methacrylate. This is because it is possible to further improve the plasticizer resistance.

  In order to solve the above-mentioned problems, the present invention comprises a film for a protective layer transfer sheet according to the present invention, and a heat seal layer formed on the release layer and containing a thermoplastic resin. A protective layer transfer sheet is provided.

  According to the present invention, since the protective layer transfer sheet film according to the present invention is used as the protective layer transfer sheet film, the substrate and the release layer are excellent in releasability and at low cost. A manufacturable protective layer transfer sheet can be obtained.

  The present invention has an effect of providing a protective layer transfer sheet that is excellent in releasability between a substrate and a release layer and can be produced at low cost.

The present invention relates to a protective layer transfer sheet used for forming a protective layer for protecting an image printed by a sublimation thermal transfer system, and a protective layer transfer sheet film used therefor.
Hereinafter, the protective layer transfer sheet of the present invention and the protective layer transfer sheet film will be described in order.

A. First, the protective layer transfer sheet film of the present invention will be described. The protective layer transfer sheet film of the present invention comprises a base material, a heat-resistant slip layer formed on the base material and containing an isocyanate compound and a hydroxyl group-containing resin, and the heat-resistant slip layer of the base material. And having a release layer containing a transparent resin material, wherein the transparent resin material has substantially no functional group having active hydrogen. Is.

Such a protective layer transfer sheet film of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view showing an example of the protective layer transfer sheet film of the present invention. As illustrated in FIG. 1, a protective layer transfer sheet film 10 of the present invention includes a base material 1, a heat resistant slipping layer 3 formed on the base material 1 and containing an isocyanate compound and a hydroxyl group-containing resin, The substrate 1 has a release layer 2 formed on the surface opposite to the surface on which the heat-resistant slip layer 3 is formed and containing a transparent resin material.
In such an example, the protective layer transfer sheet film 10 of the present invention is characterized in that the transparent resin material contained in the release layer 2 has substantially no functional group having active hydrogen. Is.

  Moreover, the film for protective layer transfer sheets of this invention is used as a protective layer transfer sheet by forming a heat seal layer on the said peeling layer.

According to the present invention, for example, the transparent resin material contained in the release layer is substantially free of a functional group having an active hydrogen having reactivity with the isocyanate compound. Even when the protective layer transfer sheet film of the invention is produced by a Roll to Roll process, it is possible to prevent the peelability between the substrate and the release layer from being impaired.
In addition, according to the present invention, as a transparent resin material for this purpose, a material having substantially no functional group having an active hydrogen that is reactive with the isocyanate compound is used as in the conventional case. Without adding a new structure such as a mold layer, a film for a protective layer transfer sheet excellent in releasability between the substrate and the release layer can be obtained.
For these reasons, by using the protective layer transfer sheet film of the present invention, it is possible to obtain a protective layer transfer sheet that is excellent in releasability between the substrate and the release layer and can be produced at low cost.

Here, as the transparent resin material used for the release layer in the present invention, by using a material that does not substantially have a functional group having active hydrogen, the substrate and the release layer are excellent in peelability, and The reason why a protective layer transfer sheet that can be produced at low cost can be obtained will be described more specifically.
In general, as a method for producing a protective layer transfer sheet film having a configuration as in the present invention, a long base is used, and a heat resistant slip containing an isocyanate compound and a hydroxyl group-containing resin on the base is used. And forming the heat-resistant slipping layer forming step of winding the laminate composed of the base material and the heat-resistant slipping layer into a roll, and unwinding the laminate to form the heat-resistant slipping layer of the base material. A method comprising a release layer forming step of forming a release layer containing a transparent resin material on a surface opposite to the surface on which the transparent resin material is formed and then winding the release layer in a roll shape is used. Such a so-called Roll to Roll process has the advantage that a protective layer transfer sheet film can be produced with high productivity.
Here, the heat-resistant slip layer formed in the heat-resistant slip layer forming step is formed by curing the isocyanate compound and the hydroxyl group-containing resin. Unreacted isocyanate compound remains. And when the unreacted isocyanate compound remains in the heat resistant slipping layer as described above, the unreacted isocyanate compound is formed when the laminate is wound into a roll in the heat resistant slipping layer forming step. In the release layer forming step, the surface of the base material on which the release layer is formed adheres. And when the transparent resin material used for the said peeling layer shows the reactivity with respect to the said isocyanate compound, when a peeling layer is formed in the base-material surface to which the said unreacted isocyanate compound adhered, the said The transparent resin material and the isocyanate compound act on the base material surface, and as a result of significantly improving the adhesion between the base material and the release layer, the peelability is lowered.
In this regard, in the present invention, a substrate on which a release layer is temporarily formed by using a material having substantially no functional group having active hydrogen that is reactive with the isocyanate compound as the transparent resin material. Even if an unreacted isocyanate compound adheres to the surface of the substrate, the transparent resin material and the unreacted isocyanate compound do not act, so that the formed release layer has excellent releasability from the substrate. It can be made.
In addition, by using a material that has substantially no functional group having active hydrogen as the transparent base material, it is possible to release with excellent releasability without adding a new structure such as a release layer. Since a layer can be formed, a protective layer transfer sheet film can be obtained at low cost.
For these reasons, the protective layer transfer sheet film of the present invention can provide a protective layer transfer sheet that is excellent in releasability between the substrate and the release layer and can be produced at low cost.

The film for a protective layer transfer sheet of the present invention has at least a heat resistant slipping layer, a substrate, and a release layer.
Hereafter, each structure used for such a protective layer transfer sheet of this invention is demonstrated in order.

1. Release Layer First, the release layer used in the present invention will be described. The release layer used in the present invention contains a transparent resin material substantially free of a functional group having active hydrogen. The release layer used in the present invention becomes a protective layer by being transferred onto the thermal transfer image receiving sheet.
The film for a protective layer transfer sheet of the present invention uses a transparent resin material substantially free of a functional group having active hydrogen as the transparent resin material, so that the peelability between the substrate and the release layer is improved. An excellent protective layer transfer sheet that can be manufactured at low cost can be obtained.
Hereinafter, such a release layer will be described in detail.

The transparent resin material used in the present invention is not particularly limited as long as it does not substantially have the functional group having active hydrogen.
Here, in the present invention, “substantially having no functional group containing active hydrogen” means that the amount of the functional group present in the transparent resin material is the peelability between the substrate and the release layer. Is within a predetermined range. Here, the “predetermined range” may be determined in accordance with the specific application of the protective layer transfer sheet film of the present invention.

  Moreover, the functional group having the active hydrogen means a group showing reactivity with an isocyanate compound contained in the heat-resistant slipping layer described later. Examples of such functional groups include a hydroxyl group, a carboxyl group, an amino group, a mercapto group, an azide group, and a urea group. The transparent resin material used in the present invention preferably has substantially no all of these functional groups.

  The release layer in the present invention constitutes a protective layer by being later thermally transferred from a substrate onto a thermal transfer image receiving sheet. Therefore, it is preferable that the transparent resin material used in the present invention is easily peelable from the substrate when heated. From such a viewpoint, it is desirable that the transparent resin material used in the present invention includes a first transparent resin having a glass point transfer (Tg) of 90 ° C. or higher. This is because by including such a first transparent resin, the release layer in the present invention can be easily peeled off from the substrate during heating. Among these, the first transparent resin used in the present invention preferably has a Tg of 80 ° C. or higher, particularly preferably 85 ° C. or higher, and more preferably in the range of 85 ° C. to 100 ° C. This is because the release layer in the present invention can be made more excellent in peelability from the substrate.

Examples of such a first transparent resin include those having no functional group containing the active hydrogen such as polymethyl methacrylate, polystyrene, polycarbonate, methyl methacrylate, styrene, and the like. Hydroxyethyl methacrylate, N-methylol acrylamide, N-methylol methacrylamide, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate , Monocarboxylic acids having the above active hydrogen such as acrylic acid, methacrylic acid, 2-carboxy-1-butene, 2-carboxy-1-pentene, 2-carboxy-1-hexene, 2-carboxy-1-heptene And a polymer having a functional group containing the active hydrogen to such an extent that the peelability is not impaired, and more specifically, methyl methacrylate, styrene, etc. And those having the active hydrogen-containing monomer copolymerized at a polymerization ratio of the active hydrogen-containing monomer of 10% or less. Among these, the first transparent resin used in the present invention preferably has no functional group containing the active hydrogen. This is because by using such a first transparent resin, the above-described peelability of the release layer used in the present invention is not impaired.
Here, the fact that the first transparent resin does not have a functional group containing the active hydrogen is that the transparent resin material is specified by, for example, the GC-MS method, the NMR method, and the structure of the specified material. It can be evaluated by referring to an expression.

  The first transparent resin used in the present invention is particularly preferably polymethyl methacrylate among those having no functional group containing active hydrogen. This is because polymethyl methacrylate is excellent in plasticizer resistance, so that the release layer in the present invention can form a protective layer excellent in long-term storage stability of the thermal transfer printed matter.

The aspect in which the first transparent resin is contained in the transparent resin material may be an aspect in which the first transparent resin and another resin are mixed and contained, or the transparent resin The resin material may be composed of only the first transparent resin. In particular, in the present invention, the former embodiment is preferable, and an embodiment in which a second transparent resin having a Tg lower than that of the first transparent resin is used as the other resin is preferable. The reason is as follows.
That is, the release layer in the present invention is required not only to have a property that it can be easily peeled off from the substrate during heating, but also to exhibit good adhesion to the substrate at room temperature. In this respect, the use of the second transparent resin having a Tg lower than that of the first transparent resin makes it easy to impart the adhesion to the release layer in the present invention.

  The second transparent resin used in the present invention is not particularly limited as long as it has a lower Tg than the first transparent resin and can impart desired adhesion to the release layer in the present invention. . Among them, the second transparent resin used in the present invention preferably has a Tg within the range of 40 ° C to 90 ° C, particularly preferably within the range of 60 ° C to 90 ° C, and more preferably 60 ° C to 80 ° C. Those within the range of ° C are preferred. It is because it becomes easy to give arbitrary adhesiveness to the peeling layer in this invention by using 2nd transparent resin whose Tg is in such a range.

  Specific examples of such a second transparent resin include a resin obtained by copolymerizing methyl methacrylate and an acrylate compound. Examples of the acrylate compound include ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and benzyl (meth) acrylate.

  In addition, when using what contained the said 1st transparent resin and the said 2nd transparent resin as a transparent resin material used for this invention, the 1st transparent resin contained in the said transparent resin material The amount of is not particularly limited as long as the desired release property can be imparted to the release layer in the present invention, depending on the types of the first transparent resin and the second transparent resin. Especially in this invention, it is preferable that content of the said 1st transparent resin is 60 mass% or more, It is preferable to exist in the range of 65 mass%-95 mass% especially, Especially 70 mass%- It is preferably within the range of 90% by mass. Because the content of the first transparent resin is within such a range, the protective layer formed by transferring the release layer of the present invention can be made excellent in plasticizer resistance. is there.

  As an aspect in which the first transparent resin and the second transparent resin are contained in the transparent resin material used in the present invention, the first transparent resin and the second transparent resin are separately provided. The aspect contained independently may be sufficient, or the aspect containing the copolymer of the said 1st transparent resin and 2nd transparent resin may be sufficient. Especially in this invention, it is preferable that it is an aspect in which the copolymer of the said 1st transparent resin and 2nd transparent resin contains. When the first transparent resin and the second transparent resin are contained in the transparent resin material as a copolymer, the first transparent resin and the second transparent resin are contained separately from each other. This is because the plasticizer resistance of the protective layer formed by transferring the release layer onto the thermal transfer image-receiving sheet can often be improved.

  The release layer used in the present invention may include a material other than the transparent resin material. Such other materials are not particularly limited as long as a desired function can be imparted to the release layer used in the present invention.

  In addition, the thickness of the peeling layer used for this invention is not specifically limited, Usually, it exists in the range of 0.5 micrometer-4.0 micrometers, Preferably it is set in the range of 0.8 micrometer-2 micrometers.

2. Next, the substrate used in the present invention will be described. The substrate used in the present invention is not particularly limited as long as it can form the release layer and the heat-resistant slip layer described later and has predetermined heat resistance and strength. Such base materials include 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 Examples include alcohol films, cellophane, cellulose derivatives such as cellulose acetate, polyethylene films, polyvinyl chloride films, nylon films, polyimide films, ionomer films, and the like. Of these, a polyethylene terephthalate film is preferably used in the present invention.

  In addition, the thickness of the base material used in the present invention is usually in the range of 0.5 μm to 50 μm, preferably in the range of 1 μm to 10 μm.

3. Heat-resistant slip layer Next, the heat-resistant slip layer used in the present invention will be described. The heat-resistant slip layer used in the present invention contains an isocyanate compound and a hydroxyl group-containing resin. In the present invention, as the transparent resin material used for the release layer, an isocyanate compound is used in the heat resistant slipping layer by using a material that does not substantially have a functional group containing active hydrogen. However, the roll-to-roll process makes it possible to produce a protective layer transfer sheet film having excellent peelability between the substrate and the release layer.
Hereinafter, such a heat resistant slipping layer will be described in detail.

  The isocyanate compound used in the present invention is not particularly limited as long as a desired slip property can be imparted to the heat-resistant slip layer in the present invention. Such an isocyanate compound is not particularly limited as long as it is used in, for example, conventionally known paints, adhesives, polyurethane synthesis and the like. Examples of such isocyanate compounds include polyisocyanates such as diisocyanate and triisocyanate. Specific examples of the polyisocyanate used in the present invention include paraphenylene diisocyanate, 1-chloro-2,4-phenyl diisocyanate, 2-chloro-1,4-phenyl diisocyanate, 2,4-toluene diisocyanate, 2,6- Toluene diisocyanate, hexamethylene diisocyanate, 4,4′-biphenylene diisocyanate, triphenylmethane triisocyanate, 4,4 ′, 4 ″ -trimethyl-3,3 ′, 2′-triisocyanate-2,4,6-tri And phenyl cyanurate.

  The hydroxyl group-containing resin used in the present invention is not particularly limited as long as it contains a hydroxyl group and can react with the isocyanate compound. Examples of such a hydroxyl group-containing resin include polyvinyl butyral, polyvinyl acetal, polyvinyl formal, polyester polyol, acrylic polyol, polyether polyol, urethane polyol, and polyester. Of these, polyvinyl butyral is preferably used in the present invention.

  The isocyanate compound and the hydroxyl group-containing resin contained in the heat-resistant slip layer used in the present invention usually exist as a polymer obtained by polymerizing each other.

  In addition, the heat-resistant slip layer used in the present invention may contain other compounds in addition to the isocyanate compound and the resin. Such other compounds are not particularly limited as long as a desired function can be imparted to the heat resistant slipping layer in the present invention. Among these, examples of the other compounds that are preferably used in the present invention include phosphate ester surfactants, alkaline substances, and particles. Examples of such phosphate ester surfactants, alkaline substances, and particles include those described in JP-A-6-247066 and JP-A-63-218395.

  The thickness of the heat-resistant slip layer used in the present invention is usually preferably in the range of 0.5 μm to 5 μm, and more preferably in the range of 1 μm to 2 μm.

4). Other Configurations The protective layer transfer sheet film of the present invention may have a configuration other than the base material, the release layer, and the heat resistant slipping layer. Such other configurations are not particularly limited as long as a desired function can be imparted to the protective layer transfer sheet film of the present invention. Among these, the other configuration that is preferably used in the present invention includes a release layer formed between the substrate and the release layer.

  Here, the film for a protective layer transfer sheet of the present invention uses the release layer by using a transparent resin material used for the release layer that does not substantially have a functional group having active hydrogen. Without any problem, the peelability between the substrate and the release layer can be improved. Therefore, although there is usually little need to use such a release layer, for example, when a higher release property is required for the release layer, a release layer is used to realize such release property. Also good.

  The material for forming the release layer is not particularly limited as long as the releasability between the substrate and the release layer can be within a desired range. Examples of such materials include silicone resins, organic resin-modified silicone resins, fluororesins, aminoalkyd resins, and polyester resins. These resins can be used in any of emulsion type, solvent type, and solventless type.

5. Method for Producing Protective Layer Transfer Sheet Film The method for producing the protective layer transfer sheet film of the present invention is not particularly limited as long as it can produce a protective layer transfer sheet film having the above-described configuration. As such a method, for example, a long base material is used, a heat resistant slipping layer is formed on the base material, and then a laminate composed of the base material and the heat resistant slipping layer is wound into a roll shape. A heat-resistant slip layer forming step, and unwinding the laminate, forming a release layer on the surface of the substrate opposite to the surface on which the heat-resistant slip layer is formed, and then winding the layer into a roll. The method which consists of a peeling layer formation process can be mentioned. According to such a so-called Roll to Roll process, the protective layer transfer sheet film of the present invention can be produced with high productivity. In the present invention, the transparent resin material is substantially free of functional groups having active hydrogen, so that even when using such a Roll to Roll process, The film for protective layer transfer sheets excellent in peelability with a peeling layer can be manufactured.

In the heat resistant slipping layer forming step, as a method of forming the heat resistant slipping layer on the base material, for example, the heat resistant slipping layer formation including the heat resistant slipping layer containing the isocyanate compound and the hydroxyl group-containing resin described above is used. A method for preparing a coating liquid for coating, and applying the coating liquid onto the substrate by a forming means such as a gravure printing method, a screen printing method, a reverse roll coating method using a gravure plate, and drying. Can do. In this case, application amount of the heat-resistant lubricating layer forming coating solution is preferably set to 0.1g ^{/ m 2} ~3.0g ^/ m 2 in solids.

Moreover, in the said peeling layer formation process, as a method of forming a peeling layer on the said base material, for example, the coating liquid for peeling layer formation containing the transparent resin material mentioned above is prepared, for example, this is gravure. Examples thereof include a method of applying ultraviolet rays and the like after applying on a substrate and drying by means of a printing method, a screen printing method, a reverse roll coating method using a gravure plate, and the like. In this case, application amount of the release layer forming coating solution is preferably set to 0.5g ^{/ m 2} ~4.0g ^/ m 2 in dry.

B. Next, the protective layer transfer sheet of the present invention will be described. The protective layer transfer sheet of the present invention uses the protective layer transfer sheet film according to the present invention.
That is, the protective layer transfer sheet of the present invention is formed on the protective layer transfer sheet film according to the present invention, a release layer of the protective layer transfer sheet film, a heat seal layer containing a thermoplastic resin, It is characterized by having.

  Such a protective layer transfer sheet of the present invention will be described with reference to the drawings. FIG. 2 is a schematic view showing an example of the protective layer transfer sheet of the present invention. As illustrated in FIG. 2, the protective layer transfer sheet 20 of the present invention includes a substrate 1, a release layer 2, and a heat resistant slipping layer 3, and the protective layer transfer sheet film 10 of the present invention. And a heat seal layer 21 containing a thermoplastic resin.

  The protective layer transfer sheet of the present invention is excellent in releasability between the substrate and the release layer by using the protective layer transfer sheet film according to the present invention as the protective layer transfer sheet film, and A protective layer transfer sheet that can be produced at low cost can be obtained.

The protective layer transfer sheet of the present invention comprises at least the protective layer transfer sheet film and the heat seal layer.
Hereafter, each structure used for such a protective layer transfer sheet of this invention is demonstrated in order.

  In addition, about the said film for protective layer transfer sheets used for this invention, since it is the same as that of what was demonstrated in the item of the said "A. film for protective layer transfer sheets", description here is abbreviate | omitted.

1. Heat Seal Layer First, the heat seal layer used in the present invention will be described. The heat seal layer used in the present invention is formed on the release layer provided in the protective layer transfer sheet film of the present invention and contains a thermoplastic resin. The heat seal layer used in the present invention bonds the release layer and the receiving layer of the thermal transfer image receiving sheet when the protective layer is formed on the thermal transfer image receiving sheet using the protective layer transfer sheet of the present invention. It has the function to do.
Hereinafter, such a heat seal layer will be described in detail.

  The thermoplastic resin used for the heat seal layer in the present invention is not particularly limited as long as it can adhere the release layer to the transfer layer of the thermal transfer image receiving sheet. Examples of such thermoplastic resins include ethylene-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate copolymer resin, polyamide resin, polyester resin, polyethylene resin, ethylene-isobutyl acrylate copolymer resin, butyral resin, polyacetic acid. Vinyl and its copolymer resins, ionomer resins, acid-modified polyolefin resins, acrylic / methacrylic (meth) acrylic resins, acrylic ester resins, ethylene / (meth) acrylic acid copolymers, ethylene / (Meth) acrylic acid ester copolymer, polymethyl methacrylate resin, cellulose resin, polyvinyl ether resin, polyurethane resin, polycarbonate resin, polypropylene resin, epoxy resin, phenol resin, vinyl resin, maleic acid resin, Al Resin, polyethylene oxide resin, urea resin, melamine resin, melamine alkyd resin, silicone resin, rubber resin, styrene butadiene styrene block copolymer (SBS), styrene isoprene styrene block copolymer (SIS), styrene ethylene Thermoplastic resins such as butylene styrene block copolymer (SEBS) and styrene ethylene propylene styrene block copolymer (SEPS) can be used. Especially in this invention, it is preferable to use the composition which can be heat-sealed at the temperature of 180 degrees C or less among the above.

In addition to the thermoplastic resin, the heat seal layer may contain fine particles that make the heat seal layer have good cutting performance. The average particle size of the fine particles is preferably 0.05 μm to 10 μm, and more preferably 0.05 μm to 6 μm. When the average particle size of the fine particles is smaller than the above range, it is difficult to improve the cutability of the heat seal layer, and when larger than the above range, the dispersibility is poor and the smoothness of the heat seal layer is poor. This is because it may be damaged.
The average particle diameter is a value measured by a laser method. The laser method is obtained by dispersing fine particles in a solvent, irradiating the dispersion solvent with a laser beam, and analyzing the light scattered by the fine particles. In the present invention, values calculated using a particle size analyzer Microtrac UPA Model-9230 manufactured by Leeds & Northrup are used.

  The content of the fine particles is not particularly limited as long as the desired fineness can be imparted to the heat seal layer in the present invention. Especially in this invention, it is preferable to exist in the range of 10 mass parts-500 mass parts with respect to 100 mass parts of said resin which comprises a heat seal layer, and it is preferable that it is 20 mass parts-200 mass parts especially. . This is because if the content of the fine particles is less than the above range, it may be difficult to give the heat seal layer a desired cut property. Further, when the amount is larger than the above range, the dispersibility of the fine particles in the heat seal layer is lowered, and the cutability of the heat seal layer may be unstable.

  As the fine particles used in the present invention, organic fine particles and / or inorganic fine particles, that is, organic fine particles, inorganic fine particles, a mixture of an organic substance and an inorganic substance, or an inorganic substance coated with an organic substance can be used.

  Examples of the inorganic fine particles include calcium carbonate, calcium silicate, clay, kaolin, talc, silica, glass, diatomaceous earth, mica powder, alumina, magnesium oxide, zinc oxide, barium sulfate, aluminum sulfate, calcium sulfate, and basic magnesium carbonate. Molybdenum disulfide can be used.

  On the other hand, the organic fine particle is preferably a thermoplastic resin having a glass transition temperature of 120 ° C. or higher. For example, WAX, polyethylene, fluorine resin, acrylic resin, methacrylic resin, phenol resin, urea resin, Thermosetting resins such as melamine resin, epoxy resin, unsaturated polyester resin, polystyrene, styrene and / or α-methylstyrene and other monomers (eg maleic anhydride, phenylmaleimide, methyl methacrylate, butadiene, acrylonitrile, etc. ) And the like (for example, AS resin, ABS resin, MBS resin, heat-resistant ABS resin, etc.) and the like can be applied.

  Here, when organic fine particles are used as the fine particles, since the refractive index with the synthetic resin constituting the heat seal layer is relatively close, the heat seal layer can provide transparency. Moreover, it has the advantage that the cutting property of the heat seal layer can be easily improved by controlling the functional group on the particle surface as compared with the inorganic fine particles.

  The shape of the fine particles used in the present invention is not particularly limited, and may be, for example, a spherical shape, a rectangular shape, a plate shape, a flake shape, a needle shape, a hollow body, or the like.

In addition, the heat seal layer in the present invention may contain additives such as a dispersant, a filler, a plasticizer, and an antistatic agent as necessary.
Here, as the antistatic agent, nonionic surfactants, anionic surfactants, cationic surfactants, polyamides, acrylic acid derivatives, and the like can be applied.

  The thickness of the heat seal layer used in the present invention is appropriately selected depending on the type of the protective layer transfer sheet, the type of the image receiving sheet, and the like, but is usually about 0.5 μm to 11 μm, preferably 0.5 μm to 6 μm. It is said to be about. This is because if the thickness is less than the above range, the thermal transfer image-receiving sheet may not be sufficiently adhered to the receiving layer. On the other hand, if the thickness is larger than the above range, the heat seal layer may be cut off or the heating temperature for transferring the protective layer may become high.

2. Other Configurations The protective layer transfer sheet of the present invention may have other configurations in addition to the protective layer transfer sheet film and the heat seal layer. Such other configurations are not particularly limited as long as a desired function can be imparted to the protective layer transfer sheet of the present invention. Among these, examples of other configurations that can be suitably used in the present invention include a dye transfer layer for printing an image.

  The dye transfer layer may be composed of a single color, or may be composed of, for example, three colors of yellow, cyan, and magenta. Such a dye transfer layer can be the same as the dye transfer layer used in a general sublimation thermal transfer sheet.

3. Method for Producing Protective Layer Transfer Sheet The method for producing the protective layer transfer sheet of the present invention is not particularly limited as long as it is a method capable of producing a protective layer transfer sheet having the above configuration. As such a method, for example, a long film is used as the protective layer transfer sheet film of the present invention, and the release layer of the protective layer transfer sheet film is unwound while unwinding the protective layer transfer sheet film. An example is a method having a heat seal layer forming step of forming a heat seal layer thereon and then winding the heat seal layer into a roll. According to such a so-called Roll to Roll process, the protective layer transfer sheet of the present invention can be produced with high productivity.

  In the heat seal layer forming step, the heat seal layer may be formed on the release layer by, for example, dispersing or dissolving the thermoplastic resin and the fine particles in a solvent to form a heat seal layer coating. After preparing the working liquid, this is roll coat, reverse roll coat, gravure coat, gravure reverse coat, comma coat, bar coat, wire bar coat, rod coat, kiss coat, knife coat, die coat, flow coat, dip coat, Examples thereof include a method of applying on the release layer by a coating method such as spray coating, and drying and / or curing.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  Hereinafter, the present invention will be described more specifically by showing examples.

1. Example 1
(1) Production of protective layer transfer sheet film a. Formation of heat-resistant slipping layer On one side of a 6 μm thick polyethylene terephthalate film (trade name Lumirror: manufactured by Toray Industries, Inc.), a coating solution for forming a heat-resistant slipping layer having the following composition is applied and dried using a gravure coater. As a result, a heat-resistant slip layer was formed and wound into a roll. At this time, the coating amount of the coating solution for forming the heat resistant slipping layer was set to 1.0 g / m ² at the time of drying. Next, it was cured by heating and aging in an oven at 60 ° C. for 5 days in a state wound in a roll.

<Composition of heat-resistant slip layer forming coating solution>
・ Polyvinyl butyral resin 3.6 parts by weight (trade name ESREC BX-1 manufactured by Sekisui Chemical Co., Ltd.)
-8.4 parts by weight of polyisocyanate (Brandnock D750: manufactured by Dainippon Ink and Company)
・ 2.8 parts by weight of phosphate ester surfactant (trade name: PRISURF A208S: manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)
・ 0.6 parts by weight of talc (trade name: Microace P-3: manufactured by Nihon Talc)
・ Solvent (toluene: methyl ethyl ketone = 1: 1) 190 parts by weight

b. Formation of Dye Transfer Layer Next, by applying an ink having the following composition on the surface opposite to the surface on which the heat-resistant slip layer of the polyethylene terephthalate long film is formed, each color is changed. A dye transfer layer was formed by setting three colors as one set so as to be 8 cm long and 4 cm wide. At this time, the distance between each set was 10 cm.

<Composition of yellow ink>
-Dye 5.5 weight part (FORON BRILLIANT YELLOW S-6GL)
・ 4.5 parts by weight of polyvinyl acetal resin (trade name KS-5: manufactured by Sekisui Chemical Co., Ltd.)
Polyethylene wax 0.1 part by weight Solvent (toluene: methyl ethyl ketone = 1: 1) 89 part by weight

<Composition of magenta ink>
-Dye 1 1.5 parts by weight (MS RED-G)
・ Dye 2 2.0 parts by weight (MACROLEX RED VIORET R)
・ 4.5 parts by weight of polyvinyl acetal resin (trade name KS-5: manufactured by Sekisui Chemical Co., Ltd.)
Polyethylene wax 0.1 part by weight Solvent (toluene: methyl ethyl ketone = 1: 1) 89 part by weight

<Cyan ink composition>
・ Dye 1.5 parts by weight (Kaya Set Blue 714)
・ 4.5 parts by weight of polyvinyl acetal resin (trade name KS-5: manufactured by Sekisui Chemical Co., Ltd.)
Polyethylene wax 0.1 part by weight Solvent (toluene: methyl ethyl ketone = 1: 1) 89 part by weight

c. Formation of Release Layer Polymethyl methacrylate (70 parts by weight) (MMA: Tg = 105 ° C.) and methyl methacrylate (MMA) -ethyl acrylate (EA) copolymer (30 parts by weight) (MMA-EA = 85- 15: Tg = 80 ° C.) was dissolved in a solvent (toluene: methyl ethyl ketone = 1: 1) so that the solid content would be 20% by mass to obtain a release layer forming coating solution. Next, the release layer-forming coating solution was applied by a bar coater to form a release layer having a thickness of 1.2 ± 0.2 μm between each set of the dye transfer layers. Thus, the film for protective layer transfer sheets was produced.

(2) Preparation of protective layer transfer sheet A vinyl chloride-vinyl acetate copolymer (trade name: 1000 ALK: manufactured by Denki Kagaku Kogyo Co., Ltd.) is dissolved in a solvent (toluene: methyl ethyl ketone = 1: 1) to form a heat seal layer. A coating solution was prepared. Subsequently, this was coated on the peeling layer of the said protective layer transfer sheet film, and the 1-micrometer-thick heat seal layer was formed, and the protective layer transfer sheet was formed.

2. Example 2
Except for using a transparent resin material consisting only of polymethyl methacrylate dissolved in a solvent (toluene: methyl ethyl ketone = 1: 1) so that the solid content is 20% by mass as the coating liquid for forming the release layer. In the same manner as in Example 1, a protective layer transfer sheet was formed.

3. Example 3
As the release layer forming coating solution, a transparent resin material composed only of polystyrene (Tg = 100 ° C.) dissolved in a solvent (toluene: methyl ethyl ketone = 1: 1) so that the solid content is 20% by mass is used. A protective layer transfer sheet was formed by the same method as in Example 1 except that.

4). Example 4
As a peeling layer forming coating solution, a transparent resin material (Tg = 103 ° C.) made of a methyl methacrylate-2-hydroxyethyl methacrylate (HEMA) (MMA-HEMA: 90-4) copolymer was used as a solvent (toluene: A protective layer transfer sheet was formed in the same manner as in Example 1 except that a solution in which the solid content was 20% by mass in methyl ethyl ketone = 1: 1) was used.

5. Comparative Example As a peeling layer-forming coating solution, a transparent resin material (Tg = 105 ° C.) made of a methyl methacrylate (MMA) -acrylic acid (AA) (MMA-AA: 93-7) copolymer, a solvent (toluene) : A protective layer transfer sheet was formed in the same manner as in Example 1 except that a solution dissolved in methyl ethyl ketone = 1: 1) so that the solid content was 20% by mass was used.

<Evaluation>
A protective layer is formed by transferring the release layer of the protective layer transfer sheet prepared in the above Examples and Comparative Examples onto the receiving layer of the thermal transfer image receiving sheet on which an image is formed, and the peelability at that time, and The plasticizer resistance of the protective layer was evaluated.
Moreover, the adhesive evaluation of the said base material and the said peeling layer in the protective layer transfer sheet in the said Example and comparative example was performed.
Each evaluation method is as follows.

(1) Peelability (printing conditions)
-Heating element average resistance: 4885Ω
・ Print density in the main scanning direction; 300 dpi
・ Print density in the sub-scanning direction; 300 dpi
・ Printing voltage: 18V
・ One line cycle; 2msec / line
・ Printing start temperature: 27 ℃
-Tone value: 255/255
・ Print width: 3cm
-Applied pulse (gradation control method); using a multi-pulse test printer that can vary the number of divided pulses from 0 to 255 in one line period and having a pulse length obtained by equally dividing one line period into 256, The duty ratio of each divided pulse was fixed to 90%, and each color of yellow, magenta, and cyan was transferred in this order to the receiving layer of the thermal transfer image receiving sheet to form a black image. Next, a protective layer was formed by printing the release layer with 255 pulses.

(Peeling condition)
The peeling force when peeling 180 ° was measured with the following apparatus.
・ Peeling device: Instron's universal material testing machine 5565
・ Peeling speed: 300 mm / min

(2) Adhesion evaluation A tape (Scotch Mending Tape MP-18) was adhered to the adhesiveness of the protective layer, and peeling was performed at a speed of 0.6 m / min in the 90 ° direction to confirm whether there was no peeling. The evaluation criteria were as follows.
○: No peeling from the substrate.
Δ: Partially peeled off.
X: It peels completely from a base material.

(3) Evaluation of plasticizer resistance The printed material on which the protective layer was transferred and a plasticized soft PVC sheet (Mitsubishi Chemical Altron # 480, thickness 400 μm) were superposed, and the load was 70.2 g / cm ² . And stored in a 50 ° C. environment for 48 hours. Thereafter, the deterioration of the image by the plasticizer was visually evaluated according to the following evaluation criteria.
○: No image transfer to the vinyl chloride sheet was observed.
Δ: Partial transfer of the image to the vinyl chloride sheet was observed.
X: Transfer of the image to the vinyl chloride sheet was observed throughout.

  The evaluation results are shown in Table 1 below. In addition, about the comparative example, since the protective layer could not be formed, the plasticizer resistance could not be evaluated.

It is the schematic which shows an example of the film for protective layer transfer sheets of this invention. It is the schematic which shows an example of the protective layer transfer sheet of this invention. It is the schematic which shows an example of a common protective layer transfer sheet.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Base material 2 ... Release layer 3 ... Heat resistant slipping layer 10 ... Film for protective layer transfer sheet 20 ... Protective layer transfer sheet 21 ... Heat seal layer 100 ... Protective layer transfer sheet 101 ... Base material 102 ... Release layer 103 ... Heat Seal layer 104… Heat-resistant slip layer

Claims (6)

A base material, a heat-resistant slip layer formed on the base material and containing an isocyanate compound and a hydroxyl group-containing resin, and formed on a surface opposite to the surface on which the heat-resistant slip layer of the base material is formed; A release layer containing a transparent resin material, and a protective layer transfer sheet film comprising:
The film for a protective layer transfer sheet, wherein the transparent resin material has substantially no functional group having active hydrogen.   The film for a protective layer transfer sheet according to claim 1, wherein the transparent resin material contains a first transparent resin having a Tg of 90 ° C or higher.   The said transparent resin material contains 2nd transparent resin whose Tg is in the range of 40 to 80 degreeC, The film for protective layer transfer sheets of Claim 1 or Claim 2 characterized by the above-mentioned.   4. The protective layer transfer sheet film according to claim 2, wherein the content of the first transparent resin in the transparent resin material is 60% by mass or more. 5.   The film for a protective layer transfer sheet according to any one of claims 2 to 4, wherein the first transparent resin is polymethyl methacrylate (PMMA).   A film for a protective layer transfer sheet according to any one of claims 1 to 5, and a heat seal layer formed on a release layer of the film for a protective layer transfer sheet and containing a thermoplastic resin. And a protective layer transfer sheet.

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