JP5600036B2 - Adhesive release polyester film for in-mold transfer materials - Google Patents

Description

  The present invention relates to an adhesive release film for an in-mold transfer material, and more particularly to an adhesive release film for an in-mold transfer material useful as a base film for a transfer foil for in-mold transfer that is transferred and printed simultaneously with molding in injection molding or the like.

Conventionally, as a transfer foil for in-mold, a polyester film is used as a base film, a release layer is provided thereon, a hard coat layer and a printing layer are applied on the release layer, and these are sequentially laminated. ing.
Such in-mold transfer foil is peeled off and separated between the release layer surface and the hard coat layer surface after molding and transfer. That is, after the molding transfer, the printed layer adheres to the surface of the molded product and is taken out as a product, and the hard coat layer becomes the outermost surface of the product. The release layer is removed from the product in a state of being provided on the base film of the transfer foil. Further, as a film suitable for an in-mold transfer foil, it has been studied to provide an adhesive layer between both layers in order to increase the adhesive force between the release layer and the base film.

In recent years, high productivity is required for processing using an in-mold transfer method, and attempts have been made to improve the molding speed. On the other hand, when handling the in-mold transfer foil, sticking of the transfer foils due to electrification and adhesion of dust and dust to the transfer foil surface may occur, thereby reducing productivity. For example, in Patent Document 1, a polyester film for a transfer material having an antistatic layer has been studied for such a problem.
Also, in Patent Document 2, it has excellent antistatic properties from the process of creating a transfer foil for in-mold to molding transfer, and there is no sticking between the transfer foils, and the release layer and the base film are peeled off during transfer. As a film for an in-mold transfer foil without a film, a film having an easy-adhesion layer on one side of a polyester film and an antistatic layer containing a release component on the other side is disclosed. In Patent Document 2, an attempt is made to make such a release component have good compatibility with an antistatic agent and that the release component does not cause printing repelling on the opposite printing surface.

On the other hand, when focusing on the release layer, the conventional release layer is formed by the shock that the slit blade hits when the layers are stacked and then cut (slit) to an appropriate width according to the size of the transfer object. In some cases, the transfer portion such as the hard coat layer and the print layer peeled off from the surface of the release layer at the slit portion. This is due to the fact that the delamination force between the release layer and the hard coat layer is very low, and not only the part that is subjected to transfer but also the part that is not subjected to transfer is excellent in peelability. Is.
Such a foil spill phenomenon is more prominent as the transfer layer is thicker, such as when the release layer has to be thick like a hard coat layer, or when there are many functional layers. Therefore, in order to prevent foil spilling at the time of slitting, when a release layer is provided on the base film, a release layer is provided on a belt-like pattern excluding a portion that hits the slit, and a hard coat layer, a printing layer, and an adhesive are formed thereon. A transfer layer comprising a layer or the like has been studied (Patent Document 3). However, such a method has a problem that a coating pattern suitable for the transfer object must be obtained.

  Patent Document 4 proposes a polyester film having a release layer with a normal peel strength of 2000 mN / cm or less on one side, as a transfer material film, instead of a conventional thermosetting release layer. It is described that a fluorine-containing resin is preferable as one of the components constituting the mold layer. However, in Patent Document 4, although a releasable film that can be easily peeled is studied, no consideration is given to foil spillage.

  Thus, the present situation is that there is a demand for a polyester film for an in-mold transfer material that does not cause foil spillage even without pattern coating and that has releasability after transfer.

JP 2004-223800 A JP 2006-187951 A Japanese Patent Laid-Open No. 11-58584 Japanese Patent Laid-Open No. 2007-111964

  The object of the present invention is to eliminate such problems of the prior art, and to provide a hard coat layer as an adhesive release layer when providing an adhesive release layer on at least one surface of a film used as a base material for an in-mold transfer foil. Adhesive release property that can be easily processed on the release layer and easily peeled off from the hard coat layer after transfer, and that does not cause foil spillage when slitting to a width that matches the size of the transfer object And providing an adhesive release polyester film for an in-mold transfer material that is useful as a base film for an in-mold transfer foil.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that a conventional release layer is a layer having a high releasability focusing only on releasability, and is specific to at least one surface of the polyester film. By providing a coating layer containing an adhesive release component and a cross-linking agent, and having a peeling force that has both adhesive force and release force functions, it has excellent hard coat processability and peelability, and with an appropriate width. When cutting (slit), it was found that the phenomenon of foil spillage was suppressed, and the present invention was completed.

That is, according to the present invention, an object of the present invention is to provide an adhesive release layer on at least one side of a polyester film, and the adhesive release layer is (A) a fluoropolymer having a glass transition temperature of 20 ° C. or lower, (B ) Containing an acrylic polymer and (C) a cross-linking agent, and the (A) fluoropolymer having a glass transition temperature of 20 ° C. or lower is a composite polymer of a vinylidene fluoride copolymer and a hydroxyl group-containing acrylic polymer, An in-mold transfer material provided with a hard coat layer, wherein the adhesive release layer has a peeling force of 0.2 N / mm or more and 0.4 N / mm or less to a hard coat layer described later by a measurement method described later Achieved by adhesive release polyester film.

Further, the adhesive release polyester film for in-mold transfer material of the present invention, as a preferred embodiment, prior to SL (B) a glass transition temperature of the acrylic polymer is 20 ° C. or less -40 ℃ or higher, (A) Glass The content of (A) fluoropolymer is 5 wt% or more and 90 wt% or less based on the total amount of the fluoropolymer having a transition temperature of 20 ° C. or less and (B) acrylic polymer, The content is 10% by weight or more and 95% by weight or less, the surface free energy of the adhesive release layer is 30 mN / m or more and 50 mN / m or less, and the adhesive release layer is applied in the process of forming the polyester film. At least one of forming an antistatic release layer on the surface opposite to the adhesive release layer of the polyester film. Including those having a.

  The polyester film of the present invention has excellent hard coat processability and releasability, and when it is cut (slit) with an appropriate width, the foil spill phenomenon is suppressed. Since it is not necessary to form a mold layer with a coating pattern suitable for an object to be transferred and a release layer can be coated on the entire surface of the transfer foil, it can be suitably used as a film for an in-mold transfer material.

Hereinafter, the present invention will be described in detail.

[Polyester film]
The polyester constituting the polyester film of the present invention is a linear saturated polyester synthesized from an aromatic dibasic acid or an ester-forming derivative thereof and a diol or an ester-forming derivative thereof. Specific examples of the polyester include polyethylene terephthalate, polyethylene isophthalate, polybutylene terephthalate, poly (1,4-cyclohexylenedimethylene terephthalate), and polyethylene-2,6-naphthalenedicarboxylate.

  The polyester may be a homopolymer, a copolymer having one of these polyesters as a main component, or a blend. Here, the “main component” is 80 mol% or more based on the number of moles of the repeating structural unit of the polyester. The ratio of the main component is preferably 85 mol% or more, and more preferably 90 mol% or more. The copolymer component or blend component is 20 mol% or less, preferably 15 mol% or less, more preferably 10 mol% or less, based on the number of moles of the repeating structural unit of the polyester. As the polyester, polyethylene terephthalate is particularly preferable because of a good balance between mechanical properties and moldability.

  The polyester film of the present invention may contain lubricant particles, a colorant, an antistatic agent, and an antioxidant within the range not impairing the problems of the present invention. When high transparency and surface flatness are required, it is preferable that lubricant particles are not substantially contained.

  The polyester film can be produced, for example, by the following method. That is, polyester is melt-extruded into a film shape, cooled and solidified with a casting drum to form an amorphous unstretched film, and the longitudinal direction (hereinafter sometimes referred to as a continuous film-forming direction, the longitudinal direction, and the MD direction) and the lateral direction (hereinafter referred to as the “non-stretched film”). , Sometimes referred to as the width direction and the TD direction). Stretching in the machine direction is, for example, at a temperature of 60 to 130 ° C., preferably 90 to 125 ° C., and stretched in the machine direction of, for example, 2.0 to 4.0 times, preferably 2.5 to 3.5 times. Stretching in the transverse direction is, for example, at a temperature of 60 to 130 ° C., preferably 90 to 125 ° C., and stretched in the transverse direction, for example, 2.0 to 5.0 times, preferably 3.0 to 4.5 times. The area magnification after biaxial stretching is preferably 13 or less.

  In addition, it is preferable to perform a heat setting process after extending | stretching a film. The heat setting treatment is preferably performed within a period of 1 to 30 seconds at a temperature higher than the final stretching temperature and lower than the melting point. For example, in the case of a polyethylene terephthalate film, it is preferable to select and heat-set at a temperature of 150 to 250 ° C. and a time of 2 to 30 seconds. At that time, it is performed under a limited shrinkage or elongation within 20%, or under a constant length, or may be performed in two or more stages.

  The center line surface roughness of the surface of the polyester film is preferably 1 to 50 nm. By setting the center line surface roughness of the surface of the polyester film within this range, an in-mold transfer film having a center line average surface roughness of 1 to 40 nm on the surface of the coating layer can be obtained.

  The thickness of the polyester film is preferably 12 to 100 μm, more preferably 25 to 75 μm from the viewpoint of handling properties and moldability when used as an in-mold transfer material, and further from the viewpoint of transparency as necessary. .

[Adhesive release layer]
The film of the present invention has an adhesive release layer containing (A) a fluoropolymer having a glass transition temperature of 20 ° C. or lower, (B) an acrylic polymer, and (C) a crosslinking agent on at least one surface of the polyester film. . Moreover, the peeling force of the hard-coat layer with respect to this adhesion release layer is 0.2 N / mm or more and 0.4 N / mm or less.
The film of the present invention is characterized in that it has an adhesive release layer having both functions of an adhesive force and a release force. Specifically, the adhesive release layer with a crosslinking agent while using a fluorine-based polymer. By providing a fluoropolymer having a low glass transition temperature as the fluoropolymer, and also using an acrylic polymer, the cohesive failure is also provided. It is possible to obtain an adhesive release layer having both functions of an adhesive force and a release force, in which the hard coat layer has a peeling force of 0.2 N / mm to 0.4 N / mm. And when an adhesive release polyester film having such an adhesive release layer is used for in-mold transfer foil applications, a hard coat agent can be applied on the adhesive release layer, and after the transfer, the hard coat layer is peeled off In addition, in slit processing, generation of foil spillage, debris and dust due to peeling of the adhesive release layer and the hard coat layer can be suppressed.

((A) Fluoropolymer)
The (A) fluoropolymer of the present invention is a fluoropolymer having a glass transition temperature of 20 ° C. or lower. The (A) fluorine-based polymer is preferably a composite polymer including a fluorine-containing polymer containing a fluorine atom (hereinafter sometimes referred to as a fluorine-containing polymer) and an acrylic polymer. The composite polymer is more preferably an aqueous dispersion of composite polymer particles of a fluorine-containing polymer and an acrylic polymer. In order to obtain such an aqueous dispersion, the acrylic polymer preferably contains a hydroxyl group.

  When a fluoropolymer having a glass transition temperature higher than 20 ° C. is used, the adhesive strength at room temperature is low, and the peel strength from the hard coat layer is low enough to satisfy the lower limit value. It is difficult to suppress sufficiently.

  The glass transition temperature of the fluoropolymer is preferably lower within such a range, but the lower limit is limited to −40 ° C. due to the nature of the polymer. The glass transition temperature of the fluoropolymer is preferably −30 ° C. or higher and 10 ° C. or lower. Adjustment of the glass transition temperature of the fluorine-based polymer can be performed by controlling the selection and blending amount of the acrylic monomer that is a copolymerization component of the fluorine-based polymer.

  The fluorine-based polymer of the present invention is preferably a composite polymer including a fluorine-containing polymer and an acrylic polymer. As a specific structure of such a composite polymer, a monomer component constituting the fluorine-containing polymer is used. Copolymer type and monomer component constituting an acrylic polymer, core / shell type with a fluorine-containing polymer as a core and an acrylic polymer as a shell, or an acrylic polymer as a core, a fluorine-containing polymer Core / shell type with a shell.

The fluorine-containing polymer constituting the fluorine-based polymer of the present invention is preferably a vinylidene fluoride polymer, which is a copolymer of vinylidene fluoride homopolymer, vinylidene fluoride and a monomer copolymerizable therewith. Examples are polymers. The weight average molecular weight of the vinylidene fluoride polymer is usually 10,000 to 200,000.
Examples of monomers copolymerizable with vinylidene fluoride include, for example, vinyl fluoride, tetrafluoroethylene, trifluorochloroethylene, hexafluoropropylene, hexafluoroisobutylene, trifluoroacrylic acid or its alkyl ester, pentafluoromethacrylic acid or its Fluorine-containing ethylenically unsaturated compounds such as alkyl esters, fluoroalkyl esters of acrylic acid or methacrylic acid, fluorine-free ethylenically unsaturated compounds such as propylene, cyclohexyl vinyl ether, hydroxyethyl vinyl ether, fluorine-free ethylenically unsaturated compounds such as butadiene, isoprene and chloroprene And a copolymer with a contained diene compound.
In the present invention, a vinylidene fluoride homopolymer, a binary copolymer vinylidene fluoride / tetrafluoroethylene copolymer, a vinylidene fluoride / hexafluoropropylene copolymer, a terpolymer fluoropolymer. Vinylidene fluoride / tetrafluoroethylene / hexafluoropropylene copolymers are preferably used, and among these, vinylidene fluoride / tetrafluoroethylene / hexafluoropropylene copolymers and vinylidene fluoride / hexafluoropropylene copolymers are particularly preferred. Preferably used. These vinylidene fluoride polymers are used alone or in combination of two or more.

  The vinylidene fluoride copolymer is preferably a copolymer having a vinylidene fluoride content of 50% by weight or more. As a specific composition ratio of the vinylidene fluoride copolymer, the vinylidene fluoride / tetrafluoroethylene copolymer is preferably 50 to 90% by weight of vinylidene fluoride and 50 to 10% by weight of tetrafluoroethylene. Yes, in the vinylidene fluoride / hexafluoropropylene copolymer, the vinylidene fluoride is preferably 50 to 90% by weight and the hexafluoropropylene is 50 to 10% by weight, and the vinylidene fluoride / tetrafluoroethylene / hexafluoropropylene In the copolymer, vinylidene fluoride is preferably 50 to 80% by weight, tetrafluoroethylene is 10 to 40% by weight, and hexafluoropropylene is 5 to 40% by weight. By using such a vinylidene fluoride copolymer, the film forming property of the pressure-sensitive adhesive release layer and the adhesion to the base polyester film are improved.

  The vinylidene fluoride polymer can be obtained by various methods such as emulsion polymerization, solution polymerization and precipitation polymerization. In the present invention, a vinylidene fluoride polymer obtained by emulsion polymerization is particularly preferably used.

  The composite polymer containing the fluorine-containing polymer and acrylic polymer of the present invention is preferably an aqueous dispersion of composite polymer particles of a fluorine-containing polymer and an acrylic polymer. The aqueous dispersion is usually produced by emulsion polymerization of an acrylic polymer monomer in an aqueous medium in the presence of fluorine-containing polymer particles. Therefore, the vinylidene fluoride polymer is preferably dispersed as particles in an aqueous medium at the stage of emulsion polymerization of the acrylic copolymer monomer.

  The method for dispersing the vinylidene fluoride polymer in the aqueous medium is not particularly limited. For example, (i) vinylidene fluoride is dispersed in the aqueous medium in the presence or absence of the copolymerizable monomer. (Ii) method of phase inversion of vinylidene fluoride polymer solution into aqueous dispersion, (iii) precipitation polymerization of vinylidene fluoride in the presence or absence of copolymerizable monomer Thereafter, a method of dispersing the produced polymer particles in an aqueous medium can be mentioned. Among these methods, the emulsion polymerization method (i) is preferable in that the aqueous dispersion of vinylidene fluoride polymer particles can be used as it is for the subsequent emulsion polymerization of an acrylic polymer.

  The average particle size of the vinylidene fluoride polymer particles varies depending on the desired average particle size. Usually, the average particle size of the vinylidene fluoride polymer particles in the aqueous dispersion is 0.03 to 0.3 μm. It is preferable that it is in the range, and more preferably 0.03 to 0.2 μm.

  (A) As a monomer component used in the acrylic polymer constituting a fluoropolymer having a glass transition temperature of 20 ° C. or lower, (a) an alkyl acrylate ester or alkyl having 1 to 18 carbon atoms in the alkyl group A carbonyl group-containing vinyl monomer other than (a) as the component (b) and at least one of methacrylic acid alkyl esters having 1 to 18 carbon atoms in the group; A polymerizable monomer may be used.

  (A) As an alkyl acrylate ester having 1 to 18 carbon atoms in the alkyl group, for example, methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, n-amyl acrylate, Examples include isoamyl acrylate, hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, and lauryl acrylate. Of these, alkyl acrylates having 4 to 12 carbon atoms in the alkyl group are preferable, and n-butyl acrylate, isobutyl acrylate, and 2-ethylhexyl acrylate are particularly preferable.

Examples of the alkyl methacrylate having 1 to 18 carbon atoms in the alkyl group include methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-amyl methacrylate, and methacrylic acid. Examples include isoamyl acid, hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, and lauryl methacrylate. Among these, alkyl methacrylates having 1 to 6 carbon atoms in the alkyl group are preferable, and methyl methacrylate is particularly preferable.
(A) component which comprises the said acrylic polymer is used individually or in mixture of 2 or more types from the above-mentioned monomer.

  Examples of the carbonyl group-containing vinyl monomer (b) other than (a) include acrolein, vinyl alkyl ketone, (meth) acrylic acid, hydroxyalkyl (meth) acrylate, and acrylamide. Among these, acrolein, dialkyl Acetone acrylamide and vinyl methyl ketone are preferred.

  The content of each monomer component constituting the acrylic polymer is 40 to 99.9% by weight of the component (a) and 0.1 to 0.1% of the component (b) based on the weight of the acrylic polymer. 60% by weight is preferable, the component (a) is preferably 60 to 99.5% by weight, and the component (b) is preferably 0.5 to 40% by weight. When other copolymerizable monomers are also included, such components are preferably used in an amount of 50% by weight or less.

  Further, among the components (a), when an acrylic acid alkyl ester and a methacrylic acid alkyl ester are used in combination, the ratio of the two is not particularly limited, but the acrylic polymer is contained in the vinylidene fluoride polymer particles. It is preferable to use 50% by weight or more of the methacrylic acid alkyl ester with respect to the total amount of the acrylic acid alkyl ester and the methacrylic acid alkyl ester.

  In order to contain a composite polymer with a fluorine-based polymer as an aqueous dispersion in the form of particles, the acrylic polymer constituting the fluorine-based polymer is preferably a hydroxyl group-containing acrylic polymer. Specifically, the acrylic polymer is an acrylic polymer obtained by copolymerizing 0.1 to 20% by weight of a hydroxyl group-containing monomer such as acrylic acid with respect to 100% by weight of the acrylic polymer. It is preferable.

  The (A) fluorine-based polymer of the present invention is preferably a composite polymer using a fluorine-containing polymer and an acrylic polymer, and a vinylidene fluoride copolymer is used as the fluorine-containing polymer. It is preferable to use a hydroxyl group-containing acrylic polymer as the acrylic polymer. By using such a fluorine-based polymer, the film forming property after coating is improved.

  The composite polymer of the fluorine-containing polymer and the acrylic polymer is preferably dispersed in the form of particles as an aqueous dispersion. Such an aqueous dispersion of composite polymer particles is 30 to 400 parts by weight, more preferably 40 to 300 parts by weight of a monomer mixture used as a raw material for the acrylic polymer in the presence of 100 parts by weight of fluorine-containing polymer particles. Part is obtained by emulsion polymerization in an aqueous medium.

  In obtaining such an aqueous dispersion of composite polymer particles, emulsion polymerization of a monomer mixture corresponding to a raw material of an acrylic polymer in the presence of fluorine-containing polymer particles can be considered as one type of seed polymerization. . Although the reaction behavior is not necessarily clear, it is considered that the added monomer is mainly absorbed or adsorbed in the fluorine-containing polymer particles, and the polymerization proceeds while the particles are swollen. Specifically, for example, it can be produced according to the method described in JP-A-5-271358.

  In the presence of the fluorine-containing polymer particles, an aqueous dispersion of the composite polymer particles is obtained by emulsion polymerization of the monomer as the raw material of the acrylic polymer in an aqueous medium, and the aqueous dispersion of the composite polymer particles is obtained. The average particle size of the body is usually about 0.04 to 3 μm. A preferable average particle diameter is 0.05 to 0.5 μm, and more preferably 0.05 to 0.3 μm. In the range where the average particle diameter is less than the lower limit, it is difficult to obtain an aqueous dispersion having a high solid content due to an increase in the viscosity of the aqueous dispersion, and in the case where a large mechanical shearing force is applied depending on use conditions, Things can easily occur. On the other hand, when the average particle diameter exceeds the upper limit, the storage stability of the aqueous dispersion may be lowered. The average particle size of the aqueous dispersion can be adjusted by appropriately selecting the size of the vinylidene fluoride polymer particles.

((B) Acrylic polymer)
The pressure-sensitive adhesive release layer of the present invention has a peeling force that also has a pressure-sensitive adhesive function by using (B) an acrylic polymer as one of the constituent components.

  Examples of the acrylic polymer include acrylic polymers having a glass transition temperature of −40 ° C. or higher and 20 ° C. or lower. If the glass transition temperature of the acrylic polymer is less than the lower limit, the cohesive force at room temperature is low, and the acrylic polymer is transferred to the hard coat layer when the hard coat layer is peeled off after hard coating (referred to as adhesive residue) May also occur. Moreover, if the glass transition temperature of the acrylic polymer is higher than the upper limit value, the adhesive strength at room temperature is low, which may result in a hard coating layer and poor in-mold moldability. Furthermore, foil burrs, foil scraps, etc. may occur during peeling after transfer. The glass transition temperature of the acrylic polymer is preferably −30 to 10 ° C., and the glass transition temperature can be controlled by selecting the acrylic monomer species, the amount of copolymerization, and the like.

  The acrylic polymer of the present invention is preferably an emulsion obtained by emulsion polymerization of a macromonomer, and can form a graft polymer having a high molecular weight side chain after polymerization. As monomers constituting the polymer component of the macromonomer, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (Meth) acrylates such as (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, and behenyl (meth) acrylate, (meth) acrylic acid, 2-hydroxyethyl (meth) acrylate, hydroxypropyl ( Examples thereof include hydroxyalkyl (meth) acrylates such as (meth) acrylate and hydroxybutyl (meth) acrylate, and (meth) acrylamides.

  Among these monomers, at least one of methyl (meth) acrylate, butyl (meth) acrylate and 2-ethylhexyl (meth) acrylate is used to obtain a macromonomer having a glass transition temperature of 20 ° C. or less. Is preferably used. These can be used alone or in combination of two or more.

  Production of a macromonomer having a graft polymer as a main component can be carried out by various known methods. In the present invention, radical polymerization is performed on the end group of a polymer skeleton produced by radical polymerization or anionic polymerization. It is preferable to use a macromonomer into which a highly acryloyl group is introduced.

In the acrylic polymer of the present invention, the monomer to be copolymerized with the macromonomer is preferably a vinyl monomer that can be emulsion-polymerized in an aqueous medium or a vinyl monomer mixture, and is a liquid at room temperature. Is preferred. Examples of vinyl monomers copolymerizable with the macromonomer include acrylate, methacrylate, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, Examples include (meth) acrylic acid esters such as 2-ethylhexyl (meth) acrylate.
Among these, acrylates and methacrylates are preferable, and these can be used alone or in combination of two or more.

(Contents of (A) fluoropolymer and (B) acrylic polymer)
The content of the (A) fluorine-based polymer is preferably 5% by weight or more and 90% by weight or less based on the total amount of the (A) fluorine-based polymer having a glass transition temperature of 20 ° C. or less and the (B) acrylic polymer. . The content of such a fluoropolymer is more preferably 40% by weight or more and 80% by weight or less.

The content of the (B) acrylic polymer is 10% by weight or more and 95% by weight or less based on the total amount of the (A) fluoropolymer having a glass transition temperature of 20 ° C. or less and the (B) acrylic polymer. preferable. The content of the acrylic polymer is more preferably 20% by weight or more and 60% by weight or less.
When the (A) fluorine-based polymer and the (B) acrylic polymer are contained in the pressure-sensitive adhesive release layer within the above ranges, both functions of the pressure-sensitive adhesive performance and the mold release performance are exhibited.

((C) Crosslinking agent)
Moreover, it is necessary to add a crosslinking agent to the adhesive release layer of the present invention in order to improve the cohesive strength of the layer. When the crosslinking agent is not added, the cohesive force of the adhesive release layer is not sufficient, and even when the (A) fluorine-based polymer of the present invention is contained, cohesive failure occurs first. Performance is not fully developed.

  As a crosslinking agent, an epoxy compound, an oxazoline compound, a melamine compound, an isocyanate compound can be illustrated, and the compound generally called a coupling agent can also be used. It is preferable to use an epoxy compound or an oxazoline compound because of easy handling and the pot life of the coating liquid, and it is also preferable to use a coupling agent.

Examples of the epoxy compound include polyepoxy compounds, diepoxy compounds, monoepoxy compounds, and the like, and more specifically, glycidyl ether compounds and glycidyl amine compounds thereof are exemplified.
As the oxazoline compound, a polymer containing an oxazoline group is preferable. Specifically, it can be prepared by polymerization of an addition polymerizable oxazoline group-containing monomer alone or with another monomer. Addition polymerizable oxazoline group-containing monomers include 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline, and the like can be mentioned, and one or a mixture of two or more thereof can be used. Among these, 2-isopropenyl-2-oxazoline is preferred because it is easily available industrially. The other monomer is not particularly limited as long as it is a monomer copolymerizable with an addition polymerizable oxazoline group-containing monomer.

  The melamine compound is preferably a compound obtained by reacting methylol melamine derivative obtained by condensation of melamine and formaldehyde with methyl alcohol, ethyl alcohol, isopropyl alcohol or the like as a lower alcohol, and a mixture thereof. Examples of the methylol melamine derivative include monomethylol melamine, dimethylol melamine, trimethylol melamine, tetramethylol melamine, pentamethylol melamine, hexamethylol melamine and the like.

  Isocyanate compounds include, for example, tolylene diisocyanate, diphenylmethane-4,4′-diisocyanate, metaxylylene diisocyanate, hexamethylene-1,6-diisocyanate, 1,6-diisocyanate hexane, an adduct of tolylene diisocyanate and hexane triol, Tolylene diisocyanate and trimethylolpropane adduct, polyol-modified diphenylmethane-4,4'-diisocyanate, carbodiimide-modified diphenylmethane-4,4'-diisocyanate, isophorone diisocyanate, 1,5-naphthalene diisocyanate, 3,3'-vitrylene- 4,4 'diisocyanate, 3,3' dimethyldiphenylmethane-4,4'-diisocyanate, metaphenylene diisocyanate and the like.

  The content of the crosslinking agent is preferably 5% by weight or more and 50% by weight or less based on the weight of the pressure-sensitive adhesive release layer. Further, the upper limit of the addition amount of the crosslinking agent is more preferably 40% by weight, further preferably 30% by weight, and particularly preferably 20% by weight. If the content of the crosslinking agent is less than the lower limit, the cohesive force of the pressure-sensitive adhesive release layer is lowered, and the release performance may not be sufficiently exhibited. On the other hand, when the content of the crosslinking agent exceeds the upper limit value, the film forming property of the pressure-sensitive adhesive release layer is deteriorated, and the coating appearance may be deteriorated.

(Surfactant)
The (A) fluoropolymer having a glass transition temperature of 20 ° C. or lower and the (B) acrylic polymer constituting the pressure-sensitive adhesive release layer of the present invention are both water-dispersed from the viewpoint of ease of handling during coating and working environment. It is preferably used in the form of a liquid or an emulsion. In order to obtain a good aqueous dispersion and emulsion form, the use of a surfactant is preferred, and a nonionic surfactant is particularly preferred because of its dispersion stability with other components of the coating liquid. The content of the surfactant is preferably in the range of 1% by weight to 15% by weight, more preferably in the range of 5% by weight to 12% by weight, based on the weight of the adhesive release layer.

[Peeling force]
The pressure-sensitive adhesive release layer of the present invention contains (A) both a fluorine polymer having a glass transition temperature of 20 ° C. or less and (B) an acrylic polymer, and (C) a cross-linking agent. The peeling force of the coat layer needs to be in the range of 0.2 N / mm to 0.4 N / mm. The peeling force is preferably 0.2 N / mm or more and 0.3 N / mm or less, and more preferably 0.24 N / mm or more and 0.30 N / mm. Here, the peeling force in the present invention is a hard coating containing 100 parts by weight of a hard coating agent (product name “5LC114H”) manufactured by DIC Graphics Co., Ltd. and 3 parts by weight of a hardener for the hard coating agent on the adhesive release layer. It is represented by a value obtained by measuring the peeling force after applying the coating composition, drying it with hot air at 150 ° C. for 1 minute and incompletely curing it with heat.

  When the adhesive release layer of the film used for in-mold transfer satisfies the above-mentioned peeling force with respect to the peeling force with the hard coat layer, the hard coat coating agent is used when creating the in-mold transfer foil. It can be applied on the adhesive release layer without causing coating omission, and it has excellent adhesion to the hard coat layer, so an unnecessary hard coat is required when slitting the in-mold transfer foil to match the size of the molded product. The foil spilling phenomenon that the layer portion is peeled can be suppressed, and the transfer foil after the in-mold transfer has excellent peelability.

  When the peeling force is less than the lower limit value, foil spillage during slit processing occurs due to poor adhesion. Moreover, in the coating layer composition in which the peeling force is less than the lower limit, as a result, coating omission is likely to occur when the hard coat coating agent is coated on the adhesive release layer. On the other hand, when the peeling force exceeds the upper limit value, the releasability is poor and it is difficult to remove the transfer foil after in-mold transfer.

  In order to obtain such peeling force characteristics, it is possible to use a fluorine polymer having the glass transition temperature of 20 ° C. or less, and simultaneously use an acrylic polymer and a crosslinking agent.

[Surface free energy]
The surface free energy of the pressure-sensitive adhesive release layer of the present invention is preferably 15 mN / m or more and 50 mN / m or less. Further, the surface free energy of the adhesive release layer is more preferably a lower limit of 25 mN / m, more preferably 30 mN / m from the viewpoint of coatability, releasability, and handleability, and the upper limit is More preferably, it is 45 mN / m.

  When the surface free energy of the pressure-sensitive adhesive release layer is larger than the upper limit value, the coatability of the hard coat agent is improved, but the adhesive force becomes too high and the hard coat layer may be inferior in the mold release property. Also, if the surface free energy of the pressure-sensitive adhesive release layer is less than the lower limit, the coatability may be deteriorated, and the releasability is too good to obtain the peeling force required in the present invention.

The surface free energy in the present invention is represented by the surface free energy γ _S (hereinafter sometimes referred to as surface tension) defined by the Fowkes extended formula represented by the following formula (I).
^{_{γ S = γ S d + γ}} S p + γ S h ··· (I)
(Represented in the above formula, gamma _S ^d is the dispersion component, gamma _S ^p is the polar component, gamma _S ^h is a hydrogen bonding component, respectively)
The Fowkes expansion formula includes a dispersion component γ _S ^d derived from London force, a polar component γ _S ^p derived from Debye force (permanent dipole moment, charge transfer), and a hydrogen bond component γ _S ^h derived from hydrogen bond force. In terms of attention, the correlation between the surface forming composition and the surface free energy is high, and further, the correlation with the peeling force is high. Conventionally, the release force of the release layer has often been examined by the surface tension according to the Fowkes formula, but the Fowkes formula only considers the dispersion force as an interaction. The present invention has found that the Fowkes formula has a low correlation between the surface forming composition and the peel force, and has been devised by Kitasaki, Hata et al. (Japan Adhesion Association paper) instead of the surface tension by the conventional Fowkes formula. 8 (3), 131-141 (1972)) using the surface free energy obtained by the extended Fowkes equation, and (A) a fluoropolymer having a glass transition temperature of 20 ° C. or less and (B) an acrylic polymer Such surface free energy can be obtained by including both components in the adhesive release layer.

The dispersion force component γ _S ^d constituting the surface free energy γ _S is preferably in the range of more than 0 mN / m and not more than 30 mN / m. The polarity of the component or dipole component _gamma ^{S p} less than 20 mN / m exceeded 0 mN / m, the hydrogen bond component _gamma ^{S h} is preferably not more than 2 mN / m exceeded 0 mN / m.

[Solvent resistance]
The pressure-sensitive adhesive release layer of the present invention is excellent in solvent resistance against a methyl ethyl ketone solvent by containing the above-mentioned fluorine-based polymer and acrylic polymer. Due to its excellent solvent resistance to methyl ethyl ketone solvent, it prevents the abrasion failure caused by solvent when a hard coat layer containing methyl ethyl ketone as a solvent is formed on the adhesive release layer, so the interface between the adhesive release layer and the hard coat layer Thus, it is possible to suppress the problem that the adhesive release layer is not cohesively broken and the hard coat layer cannot be peeled off.

[Antistatic release layer]
In the pressure-sensitive adhesive release polyester film of the present invention, it is preferable to further provide an antistatic release layer on the surface of the polyester film opposite to the pressure-sensitive adhesive release layer. Such an antistatic release layer is preferably an antistatic release coating layer provided by coating, and preferably contains an antistatic agent and a release agent. The antistatic release layer is a layer generally provided in a film for transfer material for in-mold, and is often imparted not only with chargeability but also with release properties in order to suppress sticking between transfer foils due to charging. However, a hard coat layer is not provided on such a layer, and the function required in addition to the antistatic property is usually only a release force necessary for preventing sticking between films, and an adhesive force is not required. It is a functional layer different from the pressure-sensitive adhesive release layer of the present invention.
By having such a layer, when handling the transfer foil for in-mold, it is possible to suppress sticking of the transfer foils due to electrification and adhesion of dust and dust to the transfer foil surface.

[Coating method]
In the present invention, the pressure-sensitive adhesive release layer is preferably provided on at least one surface of the polyester film, and is preferably provided on one surface. As a method for providing the pressure-sensitive adhesive release layer on the polyester film, it is preferably formed by applying the polyester film in a film forming process (sometimes referred to as in-line).
Conventionally, an easy-adhesion layer was formed on a polyester film, and after such a film was once rolled, a method of providing a release layer on the easy-adhesion layer as a base of a hard coat layer in a separate process was used. On the other hand, the feature of this method is that the pressure-sensitive adhesive release layer having the peeling force of the present invention can be directly coated on the polyester film in the process of forming the polyester film, and the process can be simplified. . Moreover, since it will dry and heat-process in a horizontal extending process, it is preferable if it apply | coats after the longitudinal stretch in the polyester film manufacturing process by a normal biaxial stretching method.

  The method of laminating the pressure-sensitive adhesive release layer on the polyester film by coating is not particularly limited, and for example, a coating method as shown in Yuji Harasaki, Tsuji Shoten, 1979, “Coating Method” can be used. Specifically, air doctor coater, blade coater, rod coater, knife coater, squeeze coater, impregnated coater, reverse roll coater, transfer roll coater, gravure coater, kiss roll coater, cast coater, spray coater, curtain coater, calendar Examples of the method include a coater, an extrusion coater, and a bar coater.

The coating amount of the coating solution is usually 4 to 30 g / m ² , preferably 5 to 20 g / m ² , and more preferably 6 to 10 g / m ² . Moreover, the thickness of the obtained adhesive release layer is preferably 0.01 to 0.2 μm, more preferably 0.01 to 0.08 μm as the thickness after drying. When the thickness of the adhesive release layer is less than the lower limit, the releasability may be insufficient, and when the upper limit is exceeded, the in-mold transfer foil polyester film further has an antistatic release layer. It may be easy to cause blocking with the antistatic release layer.

In the present invention, when the antistatic release layer is further provided, the antistatic layer is preferably provided on the surface of the polyester film opposite to the adhesive release layer. The antistatic layer is preferably provided by coating. As a coating method, the same method as that for the pressure-sensitive adhesive release layer can be used.
The thickness of the antistatic layer is preferably 0.01 to 0.2 [mu] m, more preferably 0.01 to 0.08 [mu] m, as the thickness after drying. When the thickness of the antistatic layer is less than the lower limit, the antistatic property may be insufficient, and when the thickness exceeds the upper limit, blocking with the in-mold transfer foil may easily occur.

[Film for in-mold transfer material]
The pressure-sensitive adhesive release polyester film of the present invention has an in-mold transfer by having, as a pressure-sensitive adhesive release layer, an application layer containing a specific fluorine-based polymer, an acrylic polymer and a crosslinking agent on at least one surface of the polyester film. When used as a film for materials, it has excellent adhesive release properties and processability from the in-mold transfer foil production process to the molding transfer, application of hard coat agent and peeling of the hard coat, Furthermore, foil spilling, generation of dust and foil dust at the time of slit processing, and adhesion of the generated dust and foil dust to the product surface can be suppressed, and productivity can be significantly improved.

  Moreover, conventionally, after laminating an easy-adhesion layer on a polyester film in a film production process, it was a process of laminating a release layer in which a release agent having an organic solvent composition was applied on the easy-adhesion layer in a separate process. However, the pressure-sensitive adhesive release layer of the present invention also has the effects of simplifying the process, reducing the environment, and reducing the cost.

  When the film for in-mold transfer material of the present invention has a releasable coating layer further containing an antistatic component on the surface opposite to the adhesive release layer, it is used as a film for in-mold transfer material. In addition, it has excellent antistatic properties and releasability from the process of creating a transfer foil for in-mold to molding and transfer. Sticking between transfer foils by charging and blocking, and dust and dirt on the surface of the transfer foil Etc. can be suppressed, and productivity can be remarkably improved.

Hereinafter, the present invention will be described in more detail with reference to examples. Various physical properties were evaluated by the following methods. Moreover, wt% represents weight%, and part represents weight part.
(1) Glass transition temperature measurement Using a differential scanning calorimeter (DSC SSC5200, manufactured by Seiko Instruments Inc.), the dried product of the coating solution for the adhesive release layer was used as a sample, and a sample amount of 5 mg was measured. The sample was sealed in an aluminum pan, and the temperature was raised from 25 ° C. to 300 ° C. under a temperature increase condition of 20 ° C./min in a nitrogen atmosphere, DSC measurement was performed, and the glass transition temperature was measured.
In addition, when it was not possible to determine whether the glass transition temperature caused by either the fluorine-based polymer or the acrylic-based polymer, DSC measurement was performed on each material by the above method, and the glass transition temperature was measured.

(2) Coating layer thickness The film is fixed with an embedding resin, the cross section is cut with a microtome, stained with 2% osmic acid at 60 ° C. for 2 hours, and using a transmission electron microscope (JEM2010 manufactured by JEOL Ltd.), The thickness of the coating layer was measured.

(3) Measurement of peel strength of hard coat layer on adhesive release layer The thickness of the hard coat agent coating liquid containing the thermosetting hard coat agent shown below on the surface of the adhesive release layer of the polyester film is as follows. It apply | coated so that it might become 10 micrometers, and it dried in 150 degreeC and the hot air oven for 1 minute, and produced the hard-coat layer.
An adhesive tape having a width of 18 mm (trade name “No. 405-1P” manufactured by Nichiban Co., Ltd.) was bonded to the surface of the prepared hard coat layer, and then pressure-bonded with a metal roller (linear pressure 2 kg / cm). After leaving at room temperature for 30 minutes, the adhesive tape was peeled off together with the hard coat layer, and the peeling force at that time was measured. The measurement was performed using a tensile tester under the condition of 90 ° peeling under the condition of a tensile speed of 300 mm / min. Evaluation was performed at n = 5, and the average value was obtained as the hard coat layer peeling force.

(Hard coating agent coating solution)
Prepare 100 parts by weight of a hard coat agent (product name “5LC114H”) manufactured by DIC Graphics Co., Ltd. as a hard coat agent and 3 parts by weight of a curing agent for the hard coat agent, and use MEK (methyl ethyl ketone) as a solvent as a non-volatile component. A 30% hard coating agent coating solution was prepared.

(4) Contact angle and surface free energy Automatic contact angle measuring device (manufactured by Kyowa Interface Chemical Co., Ltd.) for the adhesive release layer surface of a film sample conditioned for 24 hours under conditions of 23 ° C. and 65% RH Were used to measure static contact angles with water, methylene iodide, and n-hexadecane. Each liquid sample is measured five times, and the average value is taken as the contact angle of the film sample. Using the surface tension and surface tension component values (Table 1) of each liquid sample, the Fowkes of the following formula (I) The surface free energy of the adhesive release layer surface was calculated from the expansion formula.

γ _S = γ _S ^d + γ _S ^p + γ _S ^h (I)
(Represented in the above formula, gamma _S ^d is the dispersion component, gamma _S ^p is the polar component, gamma _S ^h is a hydrogen bonding component, respectively)

(5) Foil spillability at the time of peeling off the hard coat In the hard coat layer peeling force measurement test of the adhesive release layer, when the hard coat layer was peeled off with the adhesive tape, it was pulled by the adhesive tape, and the hard coat was peeled off excessively. The presence or absence of occurrence of foil spillage in the layer was observed and evaluated.

○: Hard coat layer peels off at the same width as the adhesive tape width △: Hard coat layer peels partially wider than the adhesive tape width ×: Overall hard coat layer peels wider than the tape width

(6) Solvent rubbing test According to the coating film deterioration evaluation of JIS-K5600-8, methyl ethyl ketone was soaked in gauze, gauze was placed on the adhesive release layer, and a total load of 150 g (150 g of jig weight, additional load) 0 g) load was applied to the surface of the coating layer while reciprocating one load, and then the coating width and scratches of the coating layer observed on the surface were observed. Was evaluated. Evaluation was observed in the range of 2 cm × 10 cm among the parts subjected to the solvent rubbing test.
◎: No peeling and scratches ····························································································: Slightly good ×: Peeling and scratches

(7) Haze of adhesive release layer
According to JIS K7136, the haze of the adhesive release layer was measured from the following formula (2) using a Nippon Denshoku Industries Co., Ltd. haze measuring device (NDH-2000). In the formula, the film haze is the haze value of the whole film in which the adhesive release layer is formed on the polyester film, and the adhesive release layer uncoated film haze is not applied with the adhesive release layer. It refers to the film haze in the state.
Antistatic release layer haze = film haze-adhesive release layer uncoated film haze (2)
A +: Less than 0.1% A: 0.1% or more and less than 0.4% B: 0.4% or more and less than 0.8% C: 0.8% or more In this evaluation, up to A satisfies practical performance. .

[Example 1]
Molten polyethylene terephthalate ([η] = 0.64 dl / g, Tg = 78 ° C.) containing 0.01 wt% of silicon oxide particles having an average particle diameter of 2 μm is extruded from a die and cooled by a cooling drum by a conventional method. After forming an unstretched film and then stretching in the longitudinal direction by a factor of 3.4, an adhesive release layer coating solution (2 wt% coating solution) comprising the coating layer constituents shown in Table 2 was applied to the surface of the film at 6 g / m ^2. (The coating layer thickness after drying is 0.04 μm), the antistatic layer coating solution (1.6 wt% coating solution) is 8 g / m ² (the coating layer thickness after drying is 0.04 μm) on the back surface of the film, Each was uniformly applied with a roll coater.
Subsequently, this coated film was subsequently dried at 105 ° C., stretched 3.5 times in the transverse direction at 140 ° C., and further heat-set at 220 ° C. to obtain a 50 μm-thick film having the coating film shown in Table 1. An axially stretched polyester film was obtained.

[Examples 2 to 4, Comparative Examples 1 to 7]
A laminated polyester film was obtained in the same manner as in Example 1 except that the composition of the coating solution was changed as shown in Table 2.

(Adhesive release layer composition)
・ Fluoropolymer A:
After replacing the inside of a 7-liter separable flask with nitrogen, vinylidene fluoride polymer particles (vinylidene fluoride / hexafluoropropylene / tetrafluoroethylene-ethylene copolymer: weight ratio) are used as polymer particles. (Wt%) 65/25/10, average particle size 0.15 μm) 100 parts, methyl methacrylate 60 parts, 2-ethylhexyl acrylate 15 parts, diacetone acrylamide 10 parts, isobutyl acrylate 10 parts, acrylic acid 5 parts, as an emulsifier 3.5 parts of sodium styrenesulfonate was put in the separable flask and heated at 80 ° C. Thereafter, 1.5 parts of 2% potassium persulfate aqueous solution was added as a polymerization initiator, polymerized at 85 to 95 ° C. for 3 hours, cooled to stop the reaction, and adjusted to pH 8 using ammonia. Furthermore, 1.5 parts of adipic acid dihydrazide was added as a hydrazine derivative and stirred for about 1 hour to obtain a composite polymer of vinylidene fluoride copolymer and acrylic polymer having a glass transition temperature of 10 ° C.
・ Fluoropolymer B:
Fluorinated acrylic emulsion (Nippon Paint Co., Ltd., trade name “FS-701E”, glass transition temperature 80 ° C.)
・ Fluoropolymer C:
Fluorinated acrylic emulsion (made by Meisei Chemical Industry Co., Ltd., trade name “Asahi Guard E061”, glass transition temperature 50 ° C.)
・ Fluoropolymer D:
Fluorine-containing resin emulsion containing 80.0 g of CF ₃ (CF ₂ ) _n CH ₂ CH ₂ OCOCH═CH ₂ (average of n = 9) and 20.0 g of acetoacetoxyethyl methacrylate (glass transition temperature −24 ° C.)

Acrylic polymer A:
Dissolve 50 parts 2-ethylhexyl acrylate macromonomer and 3 parts 2,2'-azobisisobutyronitrile in a mixture of 160 parts methyl methacrylate, 40 parts butyl acrylate, 1.0 part acrylate, and 1.2 parts methacrylate. Then, 10 parts of di-2-ethylhexyl sulfosuccinate was used as an emulsifier, and the mixture was emulsified in 90 parts of deionized water to prepare a pre-emulsion. A reaction vessel equipped with a stirrer, reflux condenser, nitrogen inlet tube, thermometer, and dropping funnel is charged with 250 parts of deionized water and 1.5 parts of pre-emulsion, and the temperature in the reaction vessel is maintained at 80 ° C. while bubbling nitrogen. 346.5 parts of the remaining pre-emulsion and 0.2 part of 2,2′-azobis (2-methylpropionamidine) disulfate were dropped using a dropping funnel and polymerized over 4 hours. The reaction was further continued and polymerized for 2 hours to obtain an acrylic polymer having a glass transition temperature of -20 ° C. The obtained acrylic polymer was filtered through a 200-mesh net, and the average particle size of the obtained polymer was 0.1 μm.
Acrylic polymer B: Acrylic emulsion (trade name “Aron A-106”, manufactured by Toa Gosei Co., Ltd., glass transition temperature 10 ° C.)
・ Crosslinking agent: Oxazoline compound (made by Nippon Shokubai Co., Ltd., trade name “Epocross WS-700”)
Surfactant: Polyoxyethylene (n = 7) lauryl ether (trade name “Naroacty N-70” manufactured by Sanyo Chemical Industries, Ltd.)

・架橋剤 ： オキサゾリン化合物（株式会社日本触媒製、商品名「エポクロスＷＳ−７００」）
・界面活性剤 ： ポリオキシエチレン（ｎ＝７）ラウリルエーテル（三洋化成株式会社製 商品名「ナロアクティーＮ−７０」） (Antistatic layer composition)
Silicone component: Epoxy group-containing silicone (trade name TSF4730 manufactured by GE Toshiba Silicone Co., Ltd.)
・ Cationic polymer:
A copolymer having a structure represented by the following formula (1) consisting of 80 mol% / methyl acrylate 15 mol% / N-methylol acrylamide 5 mol% was used.

・ Crosslinking agent: Oxazoline compound (made by Nippon Shokubai Co., Ltd., trade name “Epocross WS-700”)
Surfactant: Polyoxyethylene (n = 7) lauryl ether (trade name “Naroacty N-70” manufactured by Sanyo Chemical Industries, Ltd.)

  The polyester film of the present invention has excellent hard coat processability and releasability, and when it is cut (slit) with an appropriate width, the foil spill phenomenon is suppressed. Since it is not necessary to form a mold layer with a coating pattern suitable for an object to be transferred and a release layer can be coated on the entire surface of the transfer foil, it can be suitably used as a film for an in-mold transfer material.

Claims (6)

Having an adhesive release layer on at least one side of the polyester film, the adhesive release layer containing (A) a fluoropolymer having a glass transition temperature of 20 ° C. or less, (B) an acrylic polymer, and (C) a crosslinking agent;
The (A) fluoropolymer having a glass transition temperature of 20 ° C. or lower is a composite polymer of a vinylidene fluoride copolymer and a hydroxyl group-containing acrylic polymer,
The in-mold transfer material adhesive comprising a hard coat layer, wherein the adhesive release layer has a peeling force of 0.2 N / mm or more and 0.4 N / mm or less with respect to the following hard coat layer according to the following measurement method. Release polyester film.
[Measurement method of peeling force]
The hard coat agent coating solution shown below was applied to the surface of the pressure-sensitive adhesive release layer so that the thickness after drying was 10 μm, and dried in a hot air oven at 150 ° C. for 1 minute to prepare a hard coat layer. .
After sticking an adhesive tape with a width of 18 mm (trade name “No. 405-1P”, manufactured by Nichiban Co., Ltd.) to the surface of the hard coat layer produced, it was pressure-bonded with a metal roller (linear pressure 2 kg / cm), and at room temperature. After leaving for 30 minutes, the adhesive tape was peeled off together with the hard coat layer, and the peel force at that time was measured. The measurement was carried out using a tensile tester under conditions of 90 ° peeling under conditions of a tensile speed of 300 mm / min. Evaluation was performed at n = 5, and the average value was obtained as the hard coat layer peeling force.
[Hard coating agent coating solution]
Prepare 100 parts by weight of a hard coating agent (product name “5LC114H”) manufactured by DIC Graphics Co., Ltd. as a hard coating agent and 3 parts by weight of the curing agent for the hard coating agent, and use 30% of non-volatile components using methyl ethyl ketone as a solvent. A hard coating agent coating solution was prepared. (B) the acrylic glass transition temperature is below 20 ° C. -40 ° C. or higher is claim 1 Symbol placement in-mold transfer material for adhesive release polyester film of the polymer. (A) The content of (A) fluoropolymer is 5% by weight or more and 90% by weight or less based on the total amount of fluoropolymer having a glass transition temperature of 20 ° C. or less and (B) acrylic polymer, (B) The pressure-sensitive adhesive release polyester film for in-mold transfer material according to claim 1 or 2 , wherein the content of the acrylic polymer is 10 wt% or more and 95 wt% or less. The adhesive release polyester film for in-mold transfer materials according to any one of claims 1 to 3 , wherein the adhesive release layer has a surface free energy of 30 mN / m or more and 50 mN / m or less. The pressure-sensitive adhesive release polyester film for an in-mold transfer material according to any one of claims 1 to 4 , wherein the pressure-sensitive adhesive release layer is formed by coating in a film forming process of a polyester film. The pressure-sensitive adhesive release polyester film for an in-mold transfer material according to any one of claims 1 to 5 , further comprising an antistatic release layer on a surface opposite to the pressure-sensitive adhesive release layer of the polyester film.