JP6574109B2 - Decorative film - Google Patents

Description

  The present disclosure relates to a transparent decorative film suitable for adhesion to a metal substrate including stainless steel, iron and the like.

  In vehicles, buildings, traffic signs, signboards, packaging materials, etc., a decorative film or sheet in which a pressure sensitive adhesive layer is provided on a film substrate is used. For example, transparent decorative films are useful as an alternative to painting in outdoor and indoor marking applications such as glass decoration, backlight signs, plastic coloring, and the like.

  In outdoor marking applications, when a transparent decorative film is applied to a metal substrate, particularly a metal substrate containing stainless steel or iron, the adhesive contained in the decorative film may deteriorate over time. Such adhesive deterioration is caused by exposure to sunlight (particularly UV exposure), continuous high temperature environment provided by highly heat-storing metal substrates, and adhesion by catalytic action of metal ions released from metal substrates. It is considered that the main factors are depolymerization of the agent component (polymer), acidic groups contained in the polymer itself, and the like.

  Deterioration of the adhesive is observed as occurrence of odor such as cohesive failure of the adhesive, film shrinkage, discoloration (browning) of the adhesive, and ester odor. Usually, the deterioration of the adhesive proceeds very slowly. However, unlike a colored decorative film, in a transparent decorative film, the sunlight transmitted through the transparent film substrate is directly incident on the adhesive and the metal substrate therebelow, so that ionization of the metal contained in the metal substrate is easily promoted. . Since the depolymerization of the polymer by metal ions proceeds catalytically, the adhesive deteriorates rapidly once the metal ions are released from the metal substrate even in a small amount.

  Patent Document 1 (Japanese Patent Laid-Open No. 9-001722) states that “on a surface of stainless steel, a pressure-sensitive adhesive layer made of a non-chlorine resin film and a pressure-sensitive adhesive layer is attached, and then a vinyl chloride resin film and a pressure-sensitive film are used. "A marking film construction method characterized by laminating a decorative film made of an adhesive layer".

  Patent Document 2 (Japanese Patent Application Laid-Open No. 10-204389) states that “It is a (co) polymer of 100 parts by weight of a vinyl chloride resin and a vinyl monomer having a UV-absorbing group in the molecule, and has a weight average molecular weight of 5000. Describes a vinyl chloride resin pressure-sensitive adhesive tape for stainless steel, characterized in that an adhesive layer is laminated on one side of a vinyl chloride resin sheet comprising 0.5 to 6 parts by weight of an ultraviolet-absorbing resin of ˜20,000. ing.

JP-A-9-001722 JP-A-10-204389

  For the deterioration of the adhesive when the transparent decorative film is applied to the metal substrate, Patent Document 1 and Patent Document 2 propose a solution and disclose a short-term effect, but it is very outdoors. It has been very difficult to maintain a state in which the decorative film is adhered to the metal substrate without losing the decorative property for a long period of time, for example, 3 years or more or 5 years or more.

  The present disclosure provides a transparent decorative film capable of exhibiting a stable adhesive force for a long period of time on a metal substrate, particularly a metal substrate containing stainless steel or iron in outdoor applications.

  According to one embodiment of the present disclosure, a film layer that is transparent in a visible light region having a first surface and a second surface that faces the first surface, and transparent in a visible light region that is disposed on the second surface A decorative film suitable for adhesion to a metal substrate, the film layer comprising a benzotriazole-based UV absorber, a hydroxyphenyltriazine-based UV absorber, and a benzophenone-based UV absorber The film layer has an average transmittance of 1.5% or less at a wavelength of 280 nm to 380 nm, and the pressure-sensitive adhesive layer is generated from the metal substrate. There is provided a decorative film including a (meth) acrylic polymer having an amino group capable of forming a metal complex with a metal ion.

  The decorative film of the present disclosure exhibits a stable adhesive force for a long period of time on a metal substrate, particularly a metal substrate containing stainless steel or iron, in outdoor applications. Therefore, it is possible to impart excellent decorativeness to articles used outdoors such as vehicles, buildings, traffic signs, and signboards over a long period of time.

  The above description should not be construed as disclosing all embodiments of the present invention and all advantages related to the present invention.

It is a schematic sectional drawing of the decoration film of one embodiment of this indication. It is a schematic sectional drawing of the decoration film of another embodiment of this indication.

  Hereinafter, the present invention will be described in more detail with reference to the drawings for the purpose of illustrating representative embodiments of the present invention, but the present invention is not limited to these embodiments. With respect to the reference numbers in the drawings, elements with similar numbers in different drawings indicate similar or corresponding elements.

  In the present disclosure, the “film” includes an article called a “sheet”.

  In the present disclosure, “(meth) acryl” means acryl or methacryl, and “(meth) acrylate” means acrylate or methacrylate.

  In the present disclosure, “pressure-sensitive adhesion” means initial tackiness (tack) in the operating temperature range, for example, in the range of 0 ° C. or more and 50 ° C. or less, and adheres to various surfaces with light pressure, and phase change ( A property of a material or composition that does not exhibit (from liquid to solid).

  In the present disclosure, “transparent” means that in the visible light region (400 nm to 800 nm), the decorative film has an average light transmittance of about 60% or more, preferably about 80% or more, more preferably about 90% or more. It means having a region. The entire decorative film may be transparent, or part or a plurality of parts may be transparent.

  A decorative film according to an embodiment of the present disclosure includes a film layer that is transparent in a visible light region having a first surface and a second surface facing the first surface, and is transparent in a visible light region disposed on the second surface. And a pressure-sensitive adhesive layer, and is suitable for adhesion to a metal substrate. The film layer includes at least one UV absorber selected from the group consisting of a benzotriazole-based UV absorber, a hydroxyphenyltriazine-based UV absorber, and a benzophenone-based UV absorber, and the film layer has an average transmission at a wavelength of 280 nm to 380 nm. The rate is 1.5% or less. The pressure-sensitive adhesive layer includes a (meth) acrylic polymer having an amino group capable of forming a metal complex with metal ions generated from the metal substrate.

  Although there is no limitation in particular in the metal base material to which a decoration film is applied, For example, stainless steel, iron, copper, hot dip galvanized steel etc. can be illustrated. Metal ions generated from these metal substrates are iron ions, copper ions, zinc ions, and the like. In some embodiments, the metal substrate comprises stainless steel or iron, and the metal ions originating from the metal substrate are iron ions. The decorative film of the present disclosure can also be suitably applied to a metal substrate containing stainless steel or iron that has been difficult to adhere to a conventional transparent decorative film for a long period of time.

  FIG. 1 shows a schematic cross-sectional view of a decorative film 10 according to an embodiment of the present disclosure. The decorative film 10 includes a film layer 12 having a first surface (upper surface in FIG. 1) and a second surface (lower surface in FIG. 1) opposite to the first surface in the visible light region, And a pressure-sensitive adhesive layer 14 that is transparent in the visible light region and disposed on the two surfaces. In FIG. 1, a liner 16 is disposed on the pressure-sensitive adhesive layer 14 as an optional component. As shown in FIG. 1, the film layer 12 and the pressure-sensitive adhesive layer 14 may be directly bonded, or may be bonded via a bonding layer. Another layer, for example, a decorative layer such as a printing layer or a metal layer, a bulk layer, or the like may be interposed between the film layer 12 and the pressure-sensitive adhesive layer 14. Other layers, for example, a decorative layer such as a printing layer and a metal layer, a bulk layer, a surface protective layer, a clear layer, and the like may be laminated on the film layer. The film layer 12 may have a surface treatment such as primer treatment or corona treatment on the bonding surface with the pressure-sensitive adhesive layer 14.

  As shown in FIG. 1, the decorative film may have a liner on the surface of the pressure-sensitive adhesive layer on the side opposite to the film layer. Examples of the liner include paper; plastic materials such as polyethylene, polypropylene, polyester, and cellulose acetate; and papers coated with such plastic materials. These liners may have a surface subjected to a release treatment with silicone or the like. The thickness of the liner is generally about 5 μm or more, about 15 μm or more, or about 25 μm or more, about 300 μm or less, about 200 μm or less, or about 150 μm or less.

  A transparent resin film in the visible light region can be used as the film layer. For example, the film layer may be a resin film such as polyurethane, acrylic resin, acrylic-urethane resin, polyester, polyolefin, vinyl chloride resin, vinyl chloride-vinyl acetate resin, polycarbonate, polyimide, polyamide, polyester-amide, or a laminate thereof. May be included.

  Since it is excellent in weather resistance, it is advantageous that the film layer contains an acrylic resin film. The acrylic resin film of one embodiment includes a polymer blend of a carboxyl group-containing (meth) acrylic polymer and an amino group-containing (meth) acrylic polymer. Since the acrylic resin film containing such a polymer blend has high tensile strength and excellent elongation characteristics, it can provide a decorative film having good followability to a surface having a three-dimensional shape. The polymer blend is formed by mixing one or more carboxyl group-containing (meth) acrylic polymers and one or more amino group-containing (meth) acrylic polymers as necessary. You can also.

  As the film layer, a film formed by various molding methods such as an extruded film, an extruded stretched film, a calendar film, and a cast film, or a laminate thereof can be used. A cast film having a relatively low residual internal stress has excellent followability to the surface of a metal substrate, so that a decorative film can be adhered to a surface having a three-dimensional shape including ridges and depressions. .

  The film layer includes at least one ultraviolet absorber (UVA) selected from the group consisting of a benzotriazole-based ultraviolet absorber, a hydroxyphenyltriazine-based ultraviolet absorber, and a benzophenone-based ultraviolet absorber. These UV absorbers are excellent in compatibility with the resin contained in the film layer and can be added in large quantities, and since the UV absorbing ability is high, they penetrate the film layer and reach the pressure-sensitive adhesive layer. It is possible to effectively reduce the amount of ultraviolet rays.

Examples of the benzotriazole ultraviolet absorber include 2- (2-hydroxy-5-methylphenyl) -2H-benzotriazole, 2- (3-tert-butyl-2-hydroxy-5-methylphenyl) -5-chloro. -2H-benzotriazole, 2- (3,5-di-tert-butyl-2-hydroxyphenyl) -5-chloro-2H-benzotriazole, 2- (3,5-di-tert-butyl-2-hydroxy Phenyl) -2H-benzotriazole, 2- (3,5-di-tert-amyl-2-hydroxyphenyl) -2H-benzotriazole, 2- (2-hydroxy-5-tert-octylphenyl) -2H-benzo Triazole, 2- (2-hydroxy-4-octylphenyl) -2H-benzotriazole, 5-trifluoro Methyl-2- (2-hydroxy-3-α-cumyl-5-tert-octylphenyl) -2H-benzotriazole, 2- (2-hydroxy-3,5-di-α-cumylphenyl) -2H-benzotriazole 2- (2H-benzotriazol-2-yl) -4-methyl-6- (3,4,5,6-tetrahydrophthalimidylmethyl) phenol, 2,2′-methylenebis [4- (1,1 , 3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol], 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H- _{benzotriazole,} C 7 _{~C 9} - alkyl-3-[3- (2H-benzotriazol-2-yl) -5- (1,1-dimethylethyl) -4-hydroxyphenyl] Pro Use on ether, 2- (2H-benzotriazol-2-yl) -6- (1-methyl-1-phenylethyl) -4- (1,1,3,3-tetramethylbutyl) phenol, etc. Can do. Among them, the visible light transmittance is high UV-absorbing ability _high, C 7 -C ₉ - alkyl-3-[3- (2H-benzotriazol-2-yl) -5- (1,1-dimethylethyl) -4-hydroxyphenyl] propion ether, or 2- (2H-benzotriazol-2-yl) -6- (1-methyl-1-phenylethyl) -4- (1,1,3,3-tetramethylbutyl) ) Phenols can be used advantageously.

Examples of the hydroxyphenyltriazine-based ultraviolet absorber include 2-hydroxyphenyl-1,3,5-triazine, 2- (4,6-diphenyl-1-3,5-triazin-2-yl) -5-[( Hexyl) oxy] phenol, 2,4-bis (2-hydroxy-4-butoxyphenyl) -6- (2,4-dibutoxyphenyl) -1,3,5-triazine, 2- (2,4-dihydroxy Reaction product of (phenyl) -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine and (C ₁₀ -C ₁₆ (mainly C ₁₂ -C ₁₃ ) alkyloxy) methyloxirane Can be used. Among these, 2- (2,4-dihydroxyphenyl) -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine and (C Reaction products with _{10 to} C ₁₆ (mainly C _{12 to} C ₁₃ ) alkyloxy) methyl oxiranes can be advantageously used.

  As a benzophenone ultraviolet absorber, 2-hydroxybenzophenone, 4-hydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octyloxybenzophenone, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxy -4'-chlorobenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,4-dihydroxy-4-methoxy-5-sulfobenzophenone, 2, -Hydroxy-4-methoxybenzophenone-5-sulfonic acid hydrate can be used. Among these, when an acrylic resin film is used, 2-hydroxy-4-octyloxybenzophenone or 2,2′-dihydroxy-4-methoxybenzophenone having good compatibility with the acrylic resin can be advantageously used. .

  The ultraviolet absorber is preferably a benzotriazole ultraviolet absorber or a hydroxyphenyltriazine ultraviolet absorber, and more preferably a benzotriazole ultraviolet absorber. This is especially true for embodiments in which the film layer comprises an acrylic resin film. Without being bound by any theory, the ultraviolet absorber can be contained in a larger amount and stably in the acrylic resin due to the interaction between the carbonyl group or carboxyl group in the acrylic resin and the nitrogen-containing heterocyclic ring contained in the ultraviolet absorber. It is thought that it can be dispersed.

  In some embodiments, the film layer comprises at least one UV absorber selected from the group consisting of a benzotriazole-based UV absorber, a hydroxyphenyltriazine-based UV absorber, and a benzophenone-based UV absorber. About 2.5 parts by mass or more, about 3 parts by mass or more, or about 4 parts by mass or more with respect to parts by mass. In some embodiments, the film layer comprises at least one UV absorber selected from the group consisting of a benzotriazole-based UV absorber, a hydroxyphenyltriazine-based UV absorber, and a benzophenone-based UV absorber. About 20 parts by mass or less, about 15 parts by mass or less, or about 10 parts by mass or less with respect to parts by mass.

  An oligomer or polymer having a benzotriazole structure, a hydroxyphenyltriazine structure, or a benzophenone structure that contributes to ultraviolet absorption as a pendant group can also be used.

  The film layer is transparent in the visible light region, that is, the average transmittance of light having a wavelength of 400 to 800 nm is about 60% or more, whereas the average transmittance of light in the ultraviolet region, that is, a wavelength of 280 nm to 380 nm is about 1. 5% or less. In some embodiments, the film layer has an average transmittance of about 1.0% or less, about 0.5% or less, or about 0.3% or less at a wavelength of 280 nm to 380 nm. In this way, a film layer having a significantly reduced ultraviolet transmittance is combined with a pressure-sensitive adhesive layer containing a (meth) acrylic polymer having an amino group capable of forming a metal complex with metal ions generated from a metal substrate. Thereby, generation | occurrence | production of the metal ion which causes depolymerization of an adhesive polymer can be suppressed effectively, and a decoration film can be adhere | attached on a metal base material over a long period of time.

  The thickness of the film layer varies depending on the application, but can be generally about 5 μm or more, about 10 μm or more, or about 20 μm or more, about 1000 μm or less, about 500 μm or less, about 300 μm or less, or about 100 μm or less. In applications where the decorative film is required to be non-flammable, it is advantageous that the thickness of the film layer is about 80 μm or less, about 70 μm or less, or about 50 μm or less. When the film layer is a laminate, the above thickness means the thickness of the laminate.

  Depending on the use of the decorative film, for example, one or more conventionally known additives such as antioxidants, other ultraviolet absorbers, light stabilizers, plasticizers, lubricants, antistatic agents, flame retardants, fillers, etc. It can also be added to the film layer.

  A pressure-sensitive adhesive containing a tacky polymer can be used as the pressure-sensitive adhesive layer adhesive. As the pressure-sensitive adhesive layer, for example, a single-layer pressure-sensitive adhesive film containing an adhesive polymer, a double-sided adhesive sheet having two pressure-sensitive adhesive layers, and the like can be used.

  The pressure-sensitive adhesive layer can be formed, for example, from a coating film of a pressure-sensitive adhesive composition containing an adhesive polymer. The pressure sensitive adhesive layer may contain a crosslinked adhesive polymer. The “adhesive polymer” in the present disclosure is a polymer that has tack at normal temperature (about 25 ° C.) and imparts pressure-sensitive adhesiveness to the pressure-sensitive adhesive. As the adhesive polymer, (meth) acrylic polymer, polyurethane, polyolefin, polyester and the like can be used.

  In one embodiment, the pressure-sensitive adhesive layer includes a carboxyl group-containing (meth) acrylic polymer as a tacky polymer. The carboxyl group-containing adhesive (meth) acrylic polymer is composed mainly of a monoethylenically unsaturated monomer and a monoethylenically unsaturated monomer containing a carboxyl group (carboxyl group-containing monoethylenically unsaturated monomer). It can be obtained by copolymerization.

The monoethylenically unsaturated monomer is the main component of the polymer and generally has the formula CH ₂ = CR ¹ COOR ² (wherein R ¹ is hydrogen or a methyl group, and R ² is linear or cyclic) Or a branched alkyl group, a phenyl group, an alkoxyalkyl group, a phenoxyalkyl group, a hydroxyalkyl group, or a cyclic ether group.), Styrene, α-methylstyrene, vinyltoluene, etc. Aromatic vinyl monomers, vinyl esters such as vinyl acetate, and unsaturated nitriles such as acrylonitrile and methacrylonitrile are also included. Examples of monoethylenically unsaturated monomers represented by the formula CH ₂ = CR ¹ COOR ² include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isoamyl (meth) acrylate, 2- Methyl butyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, cyclohexyl (meth) Acrylates, alkyl (meth) acrylates such as isobornyl (meth) acrylate; phenoxyalkyl (meth) acrylates such as phenoxyethyl (meth) acrylate; methoxypropyl (meth) acrylate, 2 Alkoxyalkyl (meth) acrylates such as methoxybutyl (meth) acrylate; hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate; Examples thereof include cyclic ether-containing (meth) acrylates such as glycidyl (meth) acrylate and tetrahydrofurfuryl (meth) acrylate. As the monoethylenically unsaturated monomer, one type or two or more types of monoethylenically unsaturated monomers can be used as necessary.

  As monoethylenically unsaturated monomers containing carboxyl groups, unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid and crotonic acid; unsaturated dicarboxylic acids such as itaconic acid, fumaric acid, citraconic acid and maleic acid; ω-carboxypolycaprolactone Examples include monoacrylate, monohydroxyethyl (meth) acrylate phthalate, β-carboxyethyl acrylate, 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethyl hexahydrophthalic acid, and the like.

  In some embodiments, the glassy transition temperature (Tg) of the carboxyl group-containing tacky (meth) acrylic polymer is about 0 ° C. or less, about −20 ° C. or less, or about −40 ° C. or less, and about −80 It is at least ℃, at least about -70 ℃, or at least about -60 ℃. When Tg is lower than these ranges, the cohesive force of the pressure-sensitive adhesive tends to decrease. On the other hand, when Tg is higher than these ranges, the adhesiveness of the pressure-sensitive adhesive tends to decrease.

  The carboxyl group-containing adhesive (meth) acrylic polymer is, for example, about 80 parts by mass or more, about 85 parts by mass or more, or about 90 parts by mass or more, about 99.5 parts by mass or less, about 99 parts by mass of a monoethylenically unsaturated monomer. About 0.5 parts by mass or more, about 1 part by mass or more, or about 5 parts by mass or more, about 20 parts by mass or less, about 20 parts by mass or less, It can be obtained by copolymerization at a ratio of 15 parts by mass or less, or about 10 parts by mass or less.

  The weight average molecular weight of the carboxyl group-containing adhesive (meth) acrylic polymer is generally about 100,000 or more, about 200,000 or more, or about 300,000 or more, about 2,000,000 or less, about 1,000,000. 000 or less, or about 800,000 or less. The weight average molecular weight in the present disclosure means a molecular weight converted with standard polystyrene by GPC method.

  The carboxyl group-containing tacky (meth) acrylic polymer can be used as a main component of the pressure-sensitive adhesive composition. The blending amount of the carboxyl group-containing adhesive (meth) acrylic polymer is about 50 parts by mass or more, about 55 parts by mass or more, or 100 parts by mass of the pressure-sensitive adhesive composition in terms of solid content, or The amount can be about 60 parts by mass or more, about 99 parts by mass or less, about 95 parts by mass or less, or about 90 parts by mass or less.

  The pressure-sensitive adhesive layer is a (meth) acrylic polymer having an amino group capable of forming a metal complex with a metal ion generated from a metal substrate (hereinafter referred to as “metal complex-forming amino group-containing (meth) acrylic”). Also referred to as “polymer”). Such a metal complex-forming amino group-containing (meth) acrylic polymer can be obtained by having a monoethylenically unsaturated monomer as a main component and copolymerizing this with an amino group-containing unsaturated monomer. The metal complex-forming amino group-containing (meth) acrylic polymer forms a metal complex with metal ions released from the metal substrate, preventing or effecting depolymerization of the adhesive polymer catalyzed by these metal ions Can be suppressed. Also, metal complex-forming amino group-containing (meth) acrylic polymers, unlike low-molecular amino compounds, have a low tendency to volatilize or migrate to the outside over time. It can stay and suppress degradation of a pressure sensitive adhesive. When the adhesive polymer has a functional group such as a carbonyl group, a carboxyl group, an ester group, or a urethane group, particularly when the adhesive polymer is a carboxyl group-containing adhesive (meth) acrylic polymer, a metal complex-forming amino group The contained (meth) acrylic polymer interacts with these tacky polymers to increase the cohesive force of the pressure-sensitive adhesive and to impart excellent adhesiveness to the pressure-sensitive adhesive layer.

  The monoethylenically unsaturated monomer is the same as in the case of the carboxyl group-containing adhesive (meth) acrylic polymer. If necessary, one or more monoethylenically unsaturated monomers can be used.

  In some embodiments, the metal complex-forming amino group-containing (meth) acrylic polymer is an amino group-containing (meth) acrylic polymer that does not include a monomer unit derived from an aromatic vinyl monomer. Examples of the “aromatic vinyl monomer” include styrene, α-methylstyrene, vinyl toluene, vinyl naphthalene, vinyl anthracene, vinyl anthraquinone, aromatic amine (meth) acrylamide, and hydroxyl group-containing aromatic compound (meth) acrylate. Etc. are included. Aromatic amines include aniline, benzylamine, naphthylamine, aminoanthracene, aminoanthraquinone or derivatives thereof. Examples of the hydroxyl group-containing aromatic compound include a hydroxyl group-containing compound corresponding to the aromatic amine. In the embodiment in which the metal complex-forming amino group-containing (meth) acrylic polymer does not contain a monomer unit derived from an aromatic vinyl monomer, the coloring of the polymer is suppressed and the transparency can be maintained for a long period of time.

  As the amino group-containing unsaturated monomer, an unsaturated monomer having a primary, secondary or tertiary amino group, or a combination thereof can be used. If necessary, one or more amino group-containing unsaturated monomers can be used.

  Since there is no active hydrogen atom on the nitrogen atom, it has a metal complex-forming amino group-containing (meth) acrylic in that it has sufficient complex-forming ability for metal ions and is stable to metal substrates. The polymer is advantageously a (meth) acrylic polymer having a tertiary amino group. Such a (meth) acrylic polymer having a tertiary amino group is obtained by using an adhesive (meth) acrylic polymer having a functional group such as a carbonyl group, a carboxyl group, an ester group, or a urethane group. It is also advantageous in that the interaction is moderate and the cohesive force of the pressure sensitive adhesive is not excessively increased. A tertiary amino group can be introduced into a metal complex-forming amino group-containing (meth) acrylic polymer using an unsaturated monomer having a tertiary amino group. As unsaturated monomers having a tertiary amino group, dialkylaminoalkyl (meth) acrylates such as N, N-dimethylaminoethyl acrylate (DMAEA) and N, N-dimethylaminoethyl methacrylate (DMAEMA); N, N-dimethylamino Dialkylaminoalkyl (meth) acrylamides such as propylacrylamide (DMAPAA) and N, N-dimethylaminopropylmethacrylamide; dialkylaminoalkyl vinyl ethers such as N, N-dimethylaminoethyl vinyl ether and N, N-diethylaminoethyl vinyl ether It is done.

  The metal complex-forming amino group-containing (meth) acrylic polymer is, for example, about 80 parts by mass or more, about 85 parts by mass or more, or about 90 parts by mass or more, about 99.5 parts by mass or less of monoethylenically unsaturated monomer, About 99 parts by mass or less, or about 95 parts by mass or less, and about 0.5 parts by mass or more, about 1 part by mass or more, or about 5 parts by mass or more, about 20 parts by mass or less, about 15 parts by mass or more. It can be obtained by copolymerization in a proportion of not more than part by mass, or not more than about 10 parts by mass.

  The weight average molecular weight of the metal complex-forming amino group-containing (meth) acrylic polymer is not particularly limited. In some embodiments, the metal complex-forming amino group-containing (meth) acrylic polymer has a weight average molecular weight of about 1,000 or more, about 5,000 or more, about 10,000 or more, about 100,000 or less, About 80,000 or less, or about 70,000 or less. In such an embodiment in which the weight average molecular weight of the metal complex-forming amino group-containing (meth) acrylic polymer is relatively low, it does not volatilize but easily moves in the adhesive layer, which is advantageous for complex formation. In another embodiment, the metal complex-forming amino group-containing (meth) acrylic polymer has a weight average molecular weight of about 100,000 or more, about 200,000 or more, about 300,000 or more, about 2,000. , 000 or less, about 1,000,000 or less, or about 800,000 or less. In an embodiment in which the weight average molecular weight of the metal complex-forming amino group-containing (meth) acrylic polymer is relatively high, the metal complex-forming amino group-containing (meth) acrylic polymer functions as an adhesive polymer. A pressure-sensitive adhesive layer having a high adhesive force can be obtained.

  The compounding amount of the metal complex-forming amino group-containing (meth) acrylic polymer is about 1 part by mass or more and about 2 parts by mass or more when the total pressure-sensitive adhesive composition is 100 parts by mass in terms of solid content. About 4 parts by mass or more, about 8 parts by mass or more, about 25 parts by mass or less, about 20 parts by mass or less, or about 15 parts by mass or less.

  In some embodiments, the glass transition temperature (Tg) of the metal complex-forming amino group-containing (meth) acrylic polymer is about 0 ° C. or higher, about 20 ° C. or higher, or about 40 ° C. or higher, about 150 ° C. or lower, about 135 ° C. or lower, or about 120 ° C. or lower. In another embodiment, the metal complex-forming amino group-containing (meth) acrylic polymer has a glass transition temperature (Tg) of about 0 ° C. or lower, about −20 ° C. or lower, or about −40 ° C. or lower, about − 80 ° C. or higher, about −70 ° C. or higher, or about −60 ° C. or higher.

The glass transition temperature (Tg) of the carboxyl group-containing adhesive (meth) acrylic polymer and the metal complex-forming amino group-containing (meth) acrylic polymer is that each polymer is copolymerized from n types of monomers. It can be obtained from the formula of FOX (the following formula).

  The copolymerization of these polymers is preferably carried out by radical polymerization, and known polymerization methods such as solution polymerization, suspension polymerization, emulsion polymerization and bulk polymerization can be used. As initiators, organic peroxides such as benzoyl peroxide, lauroyl peroxide, bis (4-tert-butylcyclohexyl) peroxydicarbonate, 2,2′-azobisisobutyronitrile, 2,2′-azobis (2 -Methylbutyronitrile), dimethyl-2,2-azobis (2-methylpropionate), 4,4'-azobis (4-cyanovaleric acid), 2,2'-azobis (2-methylpropionic acid) An azo polymerization initiator such as dimethyl, 2,2′-azobis (2,4-dimethylvaleronitrile) (AVN) can be used. The amount of the initiator used is generally about 0.01 parts by mass or more, or about 0.05 parts by mass or more, about 5 parts by mass or less, or about 3 parts by mass or less with respect to 100 parts by mass of the monomer mixture.

  The pressure sensitive adhesive composition may include a crosslinking agent. The tacky polymer can be cross-linked using a cross-linking agent, thereby increasing the cohesive force of the pressure-sensitive adhesive and maintaining the adhesive force even at high temperatures. As the crosslinking agent, a compound having a site capable of reacting with a functional group or a skeleton portion of the adhesive polymer can be used. For carboxyl group-containing adhesive (meth) acrylic polymers, for example, bisamide-based crosslinking agents (for example, 1,1′-isophthaloyl-bis (2-methylaziridine)), aziridine-based crosslinking agents (for example, Japan Corporation) Catalyst-made Chemite PZ33, Avicia NeoCryl CX-100), carbodiimide-based crosslinking agent (for example, Nisshinbo Chemical Co., Ltd. Carbodilite V-03, V-05, V-07), epoxy-based crosslinking agent (for example, Soken Chemical Co., Ltd.) E-AX, E-5XM, and E5C; N, N, N ′, N′-tetraglycidyl-1,3-benzenedi (methanamine)), an isocyanate-based crosslinking agent (for example, Coronate L manufactured by Nippon Polyurethane Industry Co., Ltd.) Coronate HK, Death module H, Death module W, Death module manufactured by Bayer Le I) can be used. In one preferred embodiment, the crosslink is formed using at least one of a bisamide crosslinker and an epoxy crosslinker.

  The metal complex-forming amino group-containing (meth) acrylic polymer may be crosslinked. For metal complex-forming primary or secondary amino group-containing (meth) acrylic polymers, epoxy-based crosslinking agents (for example, E-AX, E-5XM and E5C manufactured by Soken Chemical Co., Ltd .; N, N, N ′) , N′-tetraglycidyl-1,3-benzenedi (methanamine)), isocyanate-based crosslinking agent (for example, Coronate L, Coronate HK manufactured by Nippon Polyurethane Industry Co., Ltd., Death Module H, Death Module W, Death Module I manufactured by Bayer Corporation) ) Etc. can be used.

  The addition amount of the crosslinking agent is about 0.01 parts by mass or more, about 0.03 parts by mass or more, or about 0.05 parts by mass or more, about 1.0 parts by mass or less, with respect to 100 parts by mass of the adhesive polymer. It can be about 0.5 parts by mass or less, or about 0.3 parts by mass or less.

  The pressure-sensitive adhesive composition includes talc, kaolin, calcium carbonate, aluminum flakes, fumed silica, alumina, nanoparticles and other fillers, antioxidants, UV stabilizers, tackifiers, elastic micro-components as other components. Spheres, adhesive polymer microspheres, crystalline polymers, inorganic powders, ultraviolet absorbers and the like may be included.

  The pressure-sensitive adhesive composition can be obtained by mixing a pressure-sensitive polymer, a metal complex-forming amino group-containing (meth) acrylic polymer, and other optional components using a known method.

  The pressure sensitive adhesive layer can be formed on the second surface of the film layer by a known method. For example, a pressure-sensitive adhesive layer is formed by applying a solution obtained by dissolving a pressure-sensitive adhesive composition in an organic solvent onto a liner by knife coating, bar coating, or the like and drying the solution. A decorative film can be formed by laminating a film layer on the obtained pressure-sensitive adhesive layer by dry lamination or the like.

  The thickness of the pressure sensitive adhesive layer is generally about 5 μm or more, about 10 μm or more, or about 20 μm or more, about 100 μm or less, about 80 μm or less, or about 50 μm or less.

  The pressure-sensitive adhesive layer generally forms a flat adhesive surface, but may form an uneven adhesive surface. On the uneven adhesive surface, a convex portion including an adhesive and a concave portion surrounding the convex portion are formed on the adhesive surface of the pressure-sensitive adhesive layer, and the metallic substrate is adhered to the metallic substrate. It includes an adhesive surface on which a communication path communicating with the outside is formed between the surface and the adhesive surface. An example of a method for forming the uneven adhesion surface will be described below.

  A liner having a release surface having a predetermined uneven structure is prepared. A pressure-sensitive adhesive composition is applied to the release surface of the liner and heated as necessary to form a pressure-sensitive adhesive layer. As a result, the uneven structure (negative structure) of the liner is transferred to the surface of the pressure-sensitive adhesive layer that contacts the liner (this is the adhesive surface in the decorative film), and the uneven structure has a predetermined structure (positive structure) on the adhesive surface. Form an adhesive surface. As described above, the unevenness of the bonding surface is designed in advance so as to include a groove capable of forming a communication path when the convex portion is bonded to the metal substrate.

  The groove of the pressure-sensitive adhesive layer may be arranged in a regular pattern along the regular pattern to form a regular pattern groove as long as it can prevent air bubbles remaining when applying the decorative film. Alternatively, irregular grooves may be formed by arranging irregular grooves. When the plurality of grooves are formed so as to be arranged substantially parallel to each other, it is preferable that the arrangement interval of the grooves is 10 to 2000 μm. The depth of the groove (distance from the adhesive surface to the bottom of the groove measured in the direction of the film layer) is usually about 10 μm or more and about 100 μm or less. The shape of the groove is not particularly limited as long as the effect of the present invention is not impaired. For example, the shape of the groove can be substantially rectangular (including trapezoidal), substantially semicircular, or substantially semielliptical in the cross section of the groove in the direction perpendicular to the bonding surface.

  In one embodiment, the decorative film further includes a decorative layer disposed on the first side of the film layer. The decorative film may further include a surface protective layer covering the decorative layer and the film layer. FIG. 2 shows a schematic cross-sectional view of the decorative film 10 according to such an embodiment. The decorative film 10 includes a decorative layer 26 disposed on the first surface of the film layer 12 and a surface protective layer 22 that covers the decorative layer 26 and the film layer 12. In FIG. 2, the surface protective layer 22 and the film layer 12 are bonded by the bonding layer 24.

  The decorative layer can be used for imparting decorative properties or design properties to the decorative film. Examples of the decorative layer include a printed layer and a metal layer. The decorative layer may be disposed on the entire first surface of the decorative film, or may be disposed on a part or a plurality of portions of the first surface.

  The print layer can be formed by printing on the film layer using a colorant such as toner or ink. As the printing ink, solvent-based ink or UV curable ink can be used. For printing, gravure printing, electrostatic printing, screen printing, inkjet printing, offset printing, and the like can be used.

  The thickness of the print layer can vary and can generally be about 1 μm or more, about 2 μm or more, or about 5 μm or more, about 30 μm or less, about 25 μm or less, or about 20 μm or less.

  The metal layer can be formed by depositing a metal such as indium, tin, or chromium on the film layer by vapor deposition, sputtering, or the like. A pattern or a picture can also be formed using a metal mask or the like during vapor deposition or sputtering. The thickness of the metal layer can vary and can generally be about 5 nm or more, about 10 nm or more, or about 20 nm or more, about 10 μm or less, about 5 μm or less, or about 2 μm or less.

  Various resin films or resin films with pressure-sensitive adhesives can be used as the surface protective layer. The surface protective layer desirably has flexibility and / or stretchability. Examples of the resin used for such a surface protective layer include polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyurethane, acrylic resin, polyolefin, or a combination thereof. The surface protective layer is usually transparent in the visible light region. The thickness of the surface protective layer may vary and can generally be about 10 μm or more, about 20 μm or more, or about 30 μm or more, about 200 μm or less, about 150 μm or less, or about 100 μm or less.

  The bonding layer for bonding the layers constituting the decorative film is optional, but in the case of including a bonding layer, generally used acrylic, polyolefin, polyurethane, polyester, rubber, etc., solvent type, emulsion type A pressure-sensitive, heat-sensitive, thermosetting or ultraviolet curable adhesive can be used as the bonding layer, and a thermosetting polyurethane adhesive can be advantageously used. The thickness of the bonding layer can generally be about 0.05 μm or more, about 0.5 μm or more, or about 5 μm or more, about 100 μm or less, about 50 μm or less, or about 20 μm or less.

  The decorative film of the present disclosure can be used for decoration of articles used outdoors such as vehicles, buildings, traffic signs, and signboards.

  In the present specification, the following abbreviations shown in Table 1 may be used.

  In the following examples, specific embodiments of the present disclosure are illustrated, but the present invention is not limited thereto. All parts and percentages are by weight unless otherwise specified.

<Production of adhesive polymer 1 (ADH1)>
58 parts by mass of BA, 2 parts by mass of 2EHA, 2 parts by mass of AN, and 4 parts by mass of AA were dissolved in 203 parts by mass of ethyl acetate, and 2,2′-azobis (2,4-dimethylvaleronitrile) (trade name V) as a polymerization initiator. -65, Wako Pure Chemical Industries, Ltd., Osaka, Osaka, Japan) After adding 0.2 parts by mass, the mixture was reacted at 65 ° C. for 24 hours under a nitrogen atmosphere to obtain an ethyl acetate solution of adhesive polymer 1 (ADH1) ( 33% solids) was prepared. ADH1 had a weight average molecular weight (Mw) of 500,000 and a glass transition temperature (Tg) of −53 ° C. Tg was determined from the FOX formula (the following formula) assuming that each polymer was copolymerized from n types of monomers.

<Manufacture of adhesive polymer 2 (ADH2)>
90 parts by mass of BA and 10 parts by mass of AA were dissolved in 203 parts by mass of a mixed solvent of toluene / ethyl acetate (mass ratio 50:50), and 2,2′-azobis (2,4-dimethylvaleronitrile) was used as a polymerization initiator. (Product name V-65, Wako Pure Chemical Industries, Ltd., Osaka, Osaka, Japan) After adding 0.2 part by mass, the mixture was reacted at 65 ° C. for 24 hours in a nitrogen atmosphere to obtain adhesive polymer 2 (ADH2). A toluene / ethyl acetate solution (solid content 33%) was prepared. ADH2 had a weight average molecular weight (Mw) of 630,000 and a glass transition temperature (Tg) of −44 ° C.

<Production of adhesive polymer 3 (ADH3)>
96 parts by mass of BA and 4 parts by mass of AA are dissolved in 138 parts by mass of a mixed solvent of toluene / ethyl acetate (mass ratio 50:50), and 2,2′-azobis (2,4-dimethylvaleronitrile) is used as a polymerization initiator. (Product name V-65, Wako Pure Chemical Industries, Ltd., Osaka, Osaka, Japan) After adding 0.2 part by mass, the mixture was reacted at 65 ° C. for 24 hours in a nitrogen atmosphere to obtain adhesive polymer 3 (ADH3). A toluene / ethyl acetate solution (solid content 42%) was prepared. ADH3 had a weight average molecular weight (Mw) of 580,000 and a glass transition temperature (Tg) of −54 ° C.

<Manufacture of adhesive polymer 4 (ADH4)>
90 parts by mass of 2MBA and 10 parts by mass of AA were dissolved in 150 parts by mass of ethyl acetate, and 2,2′-azobis (2,4-dimethylvaleronitrile) (trade name V-65, Wako Pure Chemical Industries, Ltd.) as a polymerization initiator. (Osaka, Osaka, Japan) After adding 0.2 parts by mass, the mixture was reacted at 65 ° C. for 24 hours under a nitrogen atmosphere to prepare an ethyl acetate solution (solid content 40%) of adhesive polymer 4 (ADH4). . ADH4 had a weight average molecular weight (Mw) of 400,000 and a glass transition temperature (Tg) of −23 ° C.

<Production of adhesive polymer 5 (ADH5)>
70 parts by mass of IOA, 22.5 parts by mass of MA, and 7.5 parts by mass of AA were dissolved in 150 parts by mass of ethyl acetate, and 2,2′-azobis (2,4-dimethylvaleronitrile) (trade name V) as a polymerization initiator. -65, Wako Pure Chemical Industries, Ltd., Osaka, Osaka, Japan) After adding 0.2 parts by mass, the mixture was reacted at 65 ° C. for 24 hours in a nitrogen atmosphere to give an ethyl acetate solution of adhesive polymer 5 (ADH5) ( 40% solids) was prepared. ADH5 had a weight average molecular weight (Mw) of 360,000 and a glass transition temperature (Tg) of −35 ° C.

<Production of metal complex-forming amino group-containing (meth) acrylic polymer 1 (AAP1)>
60 parts by mass of MMA, 34 parts by mass of BMA, and 6 parts by mass of DMAEMA were dissolved in 150 parts by mass of ethyl acetate, and dimethyl-2,2-azobis (2-methylpropionate) (trade name V-601, Wako Pure) as a polymerization initiator. Yakuhin Co., Ltd., Osaka, Osaka, Japan) After adding 0.6 part by mass, the reaction was carried out at 65 ° C. for 24 hours in a nitrogen atmosphere, and the metal complex-forming amino group-containing (meth) acrylic polymer 1 (AAP1) Of ethyl acetate (solid content 40%) was prepared. AAP1 had a weight average molecular weight (Mw) of 68,000 and a glass transition temperature (Tg) of 63 ° C.

<Production of metal complex-forming amino group-containing (meth) acrylic polymer 2 (AAP2)>
90 parts by mass of BA and 10 parts by mass of DMAEA are dissolved in 100 parts by mass of ethyl acetate, and dimethyl-2,2-azobis (2-methylpropionate) (trade name V-601, Wako Pure Chemical Industries, Ltd.) is used as a polymerization initiator. , Osaka City, Osaka, Japan) After adding 0.6 parts by mass, the mixture was reacted at 65 ° C. for 24 hours in a nitrogen atmosphere, and a metal complex-forming amino group-containing (meth) acrylic polymer 2 (AAP2) in ethyl acetate solution (50% solid content) was prepared. AAP2 had a weight average molecular weight (Mw) of 300,000 and a glass transition temperature (Tg) of −50 ° C.

<Production of carboxyl group-containing (meth) acrylic polymer 1 (CAP1)>
94 parts by mass of BA and 6 parts by mass of AA are dissolved in 203 parts by mass of ethyl acetate, and 2,2′-azobis (2,4-dimethylvaleronitrile) (trade name V-65, Wako Pure Chemical Industries, Ltd.) is used as a polymerization initiator. (Osaka City, Osaka, Japan) After adding 0.2 parts by mass, the mixture was reacted at 65 ° C. for 24 hours in a nitrogen atmosphere, and an ethyl acetate solution (solid content) of carboxyl group-containing (meth) acrylic polymer 1 (CAP1) 33%) was prepared. CAP1 had a weight average molecular weight (Mw) of 600,000 and a glass transition temperature (Tg) of −48 ° C.

  Table 2 shows the adhesive polymer, metal complex-forming amino group-containing (meth) acrylic polymer, carboxyl group-containing (meth) acrylic polymer, crosslinking agent and ultraviolet absorber used in the production of the decorative film in this example. .

<Evaluation method>
The weather resistance of the decorative film was evaluated according to the following method. The decorative film was cut into a width of 70 mm and a length of 40 mm to obtain a test piece. The test piece was affixed with a squeegee on a 1.5 mm thick stainless steel plate (SUS304). The specimen was exposed outdoors for 3 years. The appearance, odor and adhesive residue of the test piece were evaluated by a sensory test.

1. Appearance “A” (excellent) when no discoloration, shrinkage, or wrinkle was observed after 3 years of outdoor exposure, “B” when discoloration, shrinkage, or wrinkle was observed after 3 years of outdoor exposure (Poor) When the discoloration, shrinkage or wrinkle of the test piece was observed after 1 year of outdoor exposure, it was judged as “C” (very bad).

2. Odor “A” (excellent) when no odor generated from the test specimen after 3 years of outdoor exposure, “B” (bad) when odor generated from the test specimen after 3 years of outdoor exposure When odor generated from the test piece was observed after 1 year of outdoor exposure, it was judged as “C” (very bad).

3. Adhesive residue When the test piece is peeled off from the stainless steel plate, after 3 years of outdoor exposure, when the adhesive peels off without causing adhesive residue and cohesive failure, "A" (excellent), adhesive after 3 years of outdoor exposure It was judged as “B” (bad) when adhesive residue or cohesive failure was observed, and “C” (very bad) when adhesive residue or cohesive failure was found after 1 year of outdoor exposure.

<Example 1>
A transparent film solution comprising an amino group-containing (meth) acrylic polymer 1 (AAP1), a carboxyl group-containing (meth) acrylic polymer 1 (CAP1), a benzotriazole ultraviolet absorber and a crosslinking agent 1 (CL1) was prepared. . 70 parts by mass of CAP1, 8.5 parts by mass of a benzotriazole-based ultraviolet absorber, and 0.14 parts by mass of CL1 were added to 100 parts by mass of AAP1 in terms of solid content. The solid content of the solution was about 32%. The transparent film solution was applied with a knife coater to the release-treated surface of a support layer made of a 50 μm-thick polyester film having one surface subjected to a release treatment. The obtained transparent film layer was dried at 95 ° C. for 5 minutes and at 155 ° C. for 3 minutes. After drying, a transparent acrylic film having a thickness of 50 μm containing 5 parts by mass of a benzotriazole-based ultraviolet absorber per 100 parts by mass of the film layer was obtained as a film layer. The ultraviolet transmittance of the transparent acrylic film was measured according to JIS A 5759: 2008. The average transmittance of the transparent acrylic film in the ultraviolet region with a wavelength of 280 nm to 380 nm was 0.2%. A pressure-sensitive adhesive composition comprising an adhesive polymer (ADH1), AAP1 and CL1 was prepared. The mass ratio of ADH1, AAP1, and CL1 was 100: 10: 0.2 in terms of solid content. The obtained pressure-sensitive adhesive composition was applied with a knife coater onto the silicone-treated surface of a double-sided polyethylene laminate release paper having one side treated with silicone, and dried at 95 ° C. for 5 minutes. After drying, a transparent pressure-sensitive adhesive layer having a thickness of 30 μm was obtained. A transparent pressure-sensitive adhesive layer and a transparent acrylic film were bonded together to obtain a decorative film of Example 1.

<Example 2>
A decorative film of Example 2 was produced in the same manner as Example 1 except that ADH1 was changed to ADH2.

<Example 3>
A decorative film of Example 3 was produced in the same manner as in Example 1 except that ADH1 was changed to ADH3.

<Example 4>
A decorative film of Example 4 was produced in the same manner as in Example 1 except that ADH1 was changed to ADH4.

<Example 5>
A decorative film of Example 5 was produced in the same manner as in Example 1 except that ADH1 was changed to ADH5.

<Example 6>
A decorative film of Example 6 was produced in the same manner as in Example 1 except that AAP1 was changed to AAP2.

<Example 7>
A transparent acrylic film having a thickness of 30 μm containing 2.5 parts by mass of a benzotriazole-based ultraviolet absorber per 100 parts by mass of the film layer was produced in the same procedure as in Example 1. A decorative film of Example 7 was produced in the same manner as in Example 1 except that this transparent acrylic film was used as the film layer. The average transmittance of the transparent acrylic film in the ultraviolet region having a wavelength of 280 nm to 380 nm was 1.3%.

<Comparative Example 1>
Example 1 except that a film having a thickness of 30 μm containing a mixture of polyvinylidene fluoride (PVdF) and an acrylic resin containing 2 parts by mass of a benzotriazole-based ultraviolet absorber per 100 parts by mass of the film layer was used as the film layer. Similarly, a decorative film of Comparative Example 1 was produced. The average transmittance of the polyvinylidene fluoride / acrylic resin film in the ultraviolet region having a wavelength of 280 nm to 380 nm was 1.6%.

<Comparative example 2>
A decorative film of Comparative Example 2 was produced in the same manner as in Example 5 except that the film used in Comparative Example 1 was used as the film layer and AAP1 was not added to the pressure-sensitive adhesive composition.

<Comparative Example 3>
The decorative film of Comparative Example 3 is the same as Comparative Example 2 except that a polyvinyl chloride film having a thickness of 50 μm containing 5 parts by mass of a cyanoacrylate ultraviolet absorber per 100 parts by mass of the film layer is used as the film layer. Was made. The average transmittance of the polyvinyl chloride film in the ultraviolet region having a wavelength of 280 nm to 380 nm was 23.8%.

<Comparative example 4>
A decorative film of Comparative Example 4 was prepared in the same manner as Example 1 except that AAP1 was not added to the pressure sensitive adhesive composition.

  Table 3 shows the evaluation results of the decorative films of Examples 1 to 7 and Comparative Examples 1 to 4.

It will be apparent to those skilled in the art that various modifications can be made to the embodiments and examples described above without departing from the basic principles of the invention. It will also be apparent to those skilled in the art that various modifications and variations of the present invention can be made without departing from the spirit and scope of the invention. A part of the embodiment of the present invention is described in the following items [1] to [8].
[1]
A metal comprising a film layer transparent in the visible light region having a first surface and a second surface opposite to the first surface, and a pressure-sensitive adhesive layer transparent on the visible light region disposed on the second surface. A decorative film suitable for adhesion to a substrate,
The film layer includes at least one ultraviolet absorber selected from the group consisting of a benzotriazole-based ultraviolet absorber, a hydroxyphenyltriazine-based ultraviolet absorber, and a benzophenone-based ultraviolet absorber, and the film layer has a wavelength of 280 nm to 380 nm. The average transmittance at is 1.5% or less,
The pressure-sensitive adhesive layer is a decorative film including a (meth) acrylic polymer having an amino group capable of forming a metal complex with a metal ion generated from the metal substrate.
[2]
Item 2. The decorative film according to item 1, wherein the metal substrate includes stainless steel or iron, and metal ions generated from the metal substrate are iron ions.
[3]
Item 3. The decorative film according to item 1 or 2, wherein the film layer contains 2.5 parts by mass or more of the ultraviolet absorber with respect to 100 parts by mass of the film layer.
[4]
The decorative film according to any one of Items 1 to 3, wherein the film layer includes an acrylic resin film.
[5]
The decorative film according to any one of Items 1 to 4, wherein the pressure-sensitive adhesive layer contains a carboxyl group-containing tacky (meth) acrylic polymer.
[6]
Any one of Items 1 to 5, wherein the (meth) acrylic polymer having an amino group capable of forming a metal complex with a metal ion generated from the metal substrate is a (meth) acrylic polymer having a tertiary amino group. The decorative film according to Item.
[7]
Item 7. The decorative film according to any one of items 1 to 6, further including a decorative layer disposed on the first surface of the film layer.
[8]
Item 8. The decorative film according to Item 7, further comprising a surface protective layer covering the decorative layer and the film layer.

DESCRIPTION OF SYMBOLS 10 Decorative film 12 Film layer 14 Pressure-sensitive adhesive layer 16 Liner 22 Surface protective layer 24 Bonding layer 26 Decorative layer

Claims (4)

A transparent film layer in the visible light region having a first surface and a second surface opposite to the first surface, and a pressure-sensitive adhesive layer transparent on the visible light region disposed on the second surface, A decorative film suitable for adhesion to a metal substrate,
The film layer includes at least one ultraviolet absorber selected from the group consisting of a benzotriazole-based ultraviolet absorber, a hydroxyphenyltriazine-based ultraviolet absorber, and a benzophenone-based ultraviolet absorber, and the film layer has a wavelength of 280 nm to 380 nm. The average transmittance at is 1.5% or less,
The pressure-sensitive adhesive layer, said saw including a (meth) acrylic polymer having an amino group capable of forming a metal ion and the metal complex resulting from the metal substrate, wherein the film layer comprises an acrylic resin film, a decorative film.   The decorative film according to claim 1, wherein the metal substrate includes stainless steel or iron, and metal ions generated from the metal substrate are iron ions.   The decorative film according to claim 1, wherein the film layer contains 2.5 parts by mass or more of the ultraviolet absorber with respect to 100 parts by mass of the film layer. The decorative film according to any one of claims 1 to 3 , wherein the pressure-sensitive adhesive layer contains a carboxyl group-containing tacky (meth) acrylic polymer.

Images