JP5935271B2 - Film for thermal transfer and method for producing the same - Google Patents

Description

  In the present invention, for example, a transfer layer including at least a protective layer is transferred and formed on the surface of various transfer substrates such as a synthetic resin substrate, a wood substrate, an inorganic substrate, and a metal substrate. This relates to a transfer film.

  Conventionally, as a decoration method of articles, a protective layer or the like can be easily formed on the surface of various transferred substrates such as a synthetic resin base material, a wood base material, an inorganic base material, a metal base material, A transfer method using a transfer film is used. With this transfer method, a protective layer made of a resin composition having excellent surface properties such as hardness and solvent resistance is provided on a base film made of paper, a thermoplastic resin film, etc. in a peelable state, and further required According to the above, a transfer film is prepared by providing a pattern layer, an adhesive layer, etc. (hereinafter these are referred to as a transfer layer together with the protective layer), and the transfer layer surface of this transfer film is the surface of the substrate (transferred substrate). The transfer layer of the transfer film is bonded to the substrate to be transferred or the injection resin by placing the transfer film in advance in the injection mold and filling with the injection resin. This is a method for producing a desired decorative article in which a transfer layer is transferred and formed on a substrate to be transferred by peeling off at the interface with the material film and removing the substrate film. In recent years, active investigations have been made as a method of decorating automobile interior members, household appliance members, electronic device casings, and the like.

As the protective layer, a thermosetting resin is used to impart excellent surface properties such as surface hardness, abrasion resistance, scratch resistance, solvent resistance, and chemical resistance to the surface of the product after transfer. Alternatively, a curable resin such as an active energy ray curable resin is generally used, and specifically, a two-component curable polyurethane resin that is a reaction product of a polyol compound and an isocyanate compound, Various materials using an ionizing radiation curable acrylate resin having a radical polymerizable double bond have already been used (see, for example, Patent Document 1).
Also, when used as a decoration on home appliances and electronic equipment casings, in addition to the physical properties such as surface hardness, a function to protect against oil stains such as skin and sebum (called fingerprint resistance) Is also required.

  As a technique known in the coating field for the fingerprint resistance, for example, a technique of blending a fluorosurfactant with a hard coat agent and making the resulting cured film water repellent (see, for example, Patent Document 2), Hard coat agent utilizing high water repellency derived from fluorine such as a technique using a copolymer of a polymerizable monomer having a chain alkyl group and a polymerizable monomer having a polyfluoroalkyl group (see, for example, Patent Document 3) There is a technology for imparting fingerprint smudge prevention. All of these techniques using fluorine utilize the property that fluorine groups are unevenly distributed at the air interface after coating. However, as described above, the protective layer in the transfer film is provided on the base film in a peelable state, that is, since there is no air interface, fluorine groups are unevenly distributed on the surface that becomes the surface of the protective layer after transfer. There is a problem that fingerprint resistance cannot be obtained.

Japanese Patent Laid-Open No. 7-314995 JP-A-10-110118 JP 2010-24283 A

  The problem to be solved by the present invention is to provide a thermal transfer film that uses a curable resin as a protective layer, and is excellent in surface physical properties, particularly fingerprint resistance, of the resulting protective layer.

  The inventors of the present invention have solved the above problem by including a compound having a polyalkylene glycol chain and one or more (meth) acryloyl groups in the radical polymerizable resin composition layer.

  That is, the present invention is a thermal transfer film having a transfer layer in which a radical polymerizable resin composition layer and a decorative layer are laminated in this order on a base film, wherein the radical polymerizable resin composition layer is a radical film. A thermal transfer film comprising a (meth) acrylic resin having a polymerizable unsaturated group and a compound having a polyalkylene glycol chain and one or more (meth) acryloyl groups is provided.

  The present invention also provides a decorative molded product obtained by mounting the thermal transfer film described above in an injection mold and performing injection molding.

According to the present invention, a decorative molded body having excellent surface properties, particularly fingerprint resistance, can be obtained.
When adding fingerprint resistance to the surface of a decorative molded product,
・ Methods such as making attached fingerprints difficult to see and making attached fingerprints easy to wipe off are effective.
The former is not a method of reducing the affinity of the surface of the decorative molded product to the oil and fat content of the finger as much as possible and repelling or repelling the oil and fat. This is a method of making the attached portion of the oil and fat inconspicuous by making it easy to spread.
The latter is a method of making the surface easy to be removed by wiping the surface with a cloth or the like by keeping it moderate without making the surface affinity for oil and fat so strong.
The polyalkylene glycol chain used in the present invention and one or more (meth) acryloyl group-containing compounds (hereinafter sometimes referred to as “anti-fingerprint additives”) are both present on the surface of the decorative molded article. A function is added.
The film for thermal transfer of the present invention is a radically polymerizable material containing a (meth) acrylic resin having a radically polymerizable unsaturated group and an anti-fingerprint additive on the surface of the substrate film having unevenness on the surface. A resin composition layer and a decorative layer are laminated in this order to form a transfer layer. At that time, the anti-fingerprint additive is not uniformly dispersed in the transfer layer, but segregates near the contact surface between the transfer layer and the base film (release film), and as a result, covers the uneven surface of the base film. It is speculated that anti-fingerprint additives exist and minimize the gloss change due to the adhesion of oils and fats, making it easy to wipe the oils and fats.
The anti-fingerprint additive used in the present invention functions effectively particularly when the surface of the base film used in the present invention has irregularities, and exhibits excellent anti-fingerprint properties. In particular, when a fine pattern is formed on the surface of a decorative molded article using a substrate film having fine irregularities, the oil and fat content of the fingerprint tends to accumulate in the valleys of the irregular pattern. If the oil and fat is accumulated in the valley, the distinction between the convex portion and the concave portion is lost, and the fine pattern formed at the corner becomes invisible. In order to prevent this, it is necessary to reduce the content of the anti-fingerprint additive, and in the case of the anti-fingerprint agent used in the present invention, excellent fingerprint resistance can be exhibited even if the amount used is reduced. .

(Base film)
The base film used in the present invention is not particularly limited, and a known base film for thermal transfer can be used. Specifically, for example, a film made of heat-resistant resin such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyamide 6, 66 (PA6, PA66), polyimide (PI), polyvinyl alcohol (PVA) or the like is preferably used. . Among these, a film made of PET resin is most preferably used because it is excellent in cost and beauty. The thickness of the base film is preferably 20 to 125 μm, but is preferably 35 to 75 μm in consideration of followability to a three-dimensional shape.

(Uneven pattern on base film)
The substrate film used in the present invention may have a concavo-convex pattern formed on at least one of its surfaces. The uneven pattern is not particularly limited, and may be a pattern such as streaks, dots, geometric patterns, art designs, etc., hairline, emboss, mat, wood grain, line, satin, sand texture, Examples include sand patterns, ground patterns, fabric patterns, and letters.
The depth of the unevenness is not particularly limited, but a large unevenness difference applies a force to a thin portion during molding, and the film is easily torn. Therefore, it is preferable to limit the depth to 1/2 the thickness of the base film.

  A release layer may be provided between the base film and a transfer layer described later. The release layer functions as a layer for releasing the transfer layer and the base material film, which are transferred to the substrate to be transferred or the injection-molded product that is a molded product of the injection resin. The release layer is required to have a release property from the transfer layer, but is also required to have an adhesive property between the base film and the transfer layer so that the transfer layer does not release from the release layer.

  As the release layer, those usually used may be used, and release agents such as silicone resin, fluororesin, cellulose derivative resin, urea resin, polyolefin resin, and melamine resin can be used. For example, when a PET resin film is used as the base film, a silicone resin release agent having an appropriate releasability is suitably used. The release layer can be applied using a roll coater or the like. In addition, when unevenness is provided on the base film, the release agent tends to accumulate in the recesses and it is difficult to control the thickness to a uniform thickness, but the average thickness calculated from the coating weight per unit area is 0. 0.01 μm to 5 μm is preferable. Moreover, since the design property will change if the unevenness | corrugation provided in the base film is filled more than necessary, it is more preferable that the average thickness of a mold release layer is 0.01 micrometer-2 micrometers.

(Transfer layer)
In the thermal transfer film of the present invention, the transfer layer includes at least a radical polymerizable resin composition layer that is an outermost layer of a transfer body obtained by transferring to a transfer substrate, and the radical polymerizable resin composition layer. It is a layer which has at least a decorating layer between the transfer target substrate.
On the base film, the radical polymerizable resin composition layer and the decorative layer are laminated in this order so that the decorative layer is between the radical polymerizable resin composition layer and the substrate to be transferred. Provide to do. In addition to the radical polymerizable resin composition layer and the decorative layer, an adhesive layer or a layer such as an intermediate layer for concealing unevenness on the surface of the substrate to be transferred may be provided.

(Transfer layer Radical polymerizable resin composition layer)
The radical polymerizable resin composition layer used in the present invention contains a (meth) acrylic resin having a radical polymerizable unsaturated group, a compound having a polyalkylene glycol chain and one or more (meth) acryloyl groups.

(Compound having a polyalkylene glycol chain and one or more (meth) acryloyl groups)
The compound having a polyalkylene glycol chain and one or more (meth) acryloyl groups is a compound having one or more polyalkylene glycol chains and one or more (meth) acryloyl groups in the same molecule. For example, a compound in which polyalkylene glycol is bonded to the hydroxyl group of trimethylolpropane, pentaerythritol, dipentaerythritol, and the other terminal hydroxyl group of polyalkylene glycol is (meth) acrylated by dehydration esterification reaction, etc. Examples thereof include compounds in which the polyalkylene glycol possessed is (meth) acrylated by a dehydration esterification reaction or the like.
In the present invention, the polyalkylene glycol is, for example, polyethylene glycol such as monoethylene glycol, diethylene glycol, triethylene glycol, or polyethylene glycol, for example, polypropylene glycol such as monopropylene glycol, dipropylene glycol, tripropylene glycol, or polypropylene glycol, 1, 3 -Propanediol, 1,2-butanediol, 1,4-butanediol, 2,3-butanediol, 1,6-hexanediol, paraxylylene glycol, 1,4-cyclohexanediol and the like.
In the present invention, polyalkylene glycol (meth) acrylate and polyalkylene glycol di (meth) acrylate are preferably used. Polyethylene glycol methacrylate, polyethylene glycol dimethacrylate, polypropylene glycol methacrylate, polypropylene glycol dimethacrylate, polytetramethylene glycol methacrylate Polytetramethylene glycol dimethacrylate is more preferable, and polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, and polytetramethylene glycol dimethacrylate are particularly preferable.
The weight average molecular weight (Mw) of the compound having a polyalkylene glycol chain and one or more (meth) acryloyl groups is preferably 100 to 2000, and more preferably 200 to 1600. The average repeating unit number n of the polyalkylene glycol chain represented by-(RO) n- (R is an alkylene group) is preferably 1 to 45, more preferably 2 to 45. In the present invention, it may be expressed as “polyalkylene glycol” including the case where the number of repeating alkylene glycols is n = 1.
Specific examples of the polyalkylene glycol (meth) acrylate include Blemmer PDE-400 (polyethylene glycol-dimethacrylate, n = 9), Blemmer PDP-400N (polypropylene glycol-dimethacrylate, n = 7), Blemmer PDT-650. (Polytetramethylene glycol dimethacrylate, n = 9) (all manufactured by NOF Corporation), and the like.

  The compound having a polyalkylene glycol chain and one or more (meth) acryloyl groups is preferably added in an amount of 0.1 to 20% by weight, based on the total solid content of the radical polymerizable resin composition, 0.5 to 7 A range of wt% is more preferred, and a range of 0.5-5 wt% is most preferred. Although depending on the composition of the radical polymerizable resin composition, if it is less than 0.1%, there is a risk of insufficient fingerprint resistance, and if the amount used is increased, the radical polymerizable resin composition is plasticized and the coating film hardness decreases. There is a risk. In addition, when a base film having irregularities on the surface is used, the oil and fat content of the fingerprint is likely to accumulate in the valleys of the irregular pattern, and the fine patterns formed at the corners are not easily visible.

((Meth) acrylic resin having radically polymerizable unsaturated group)
The (meth) acrylic resin having a radically polymerizable unsaturated group used in the present invention is not particularly limited, and a (meth) acrylic resin obtained by a known method can be used. Specifically, for example, methyl methacrylate, ethyl methacrylate, butyl methacrylate, hydroxyethyl methacrylate, cyclohexyl methacrylate, ethyl hexyl methacrylate, methyl acrylate, ethyl acrylate, butyl acrylate, hydroxyethyl acrylate, acrylic acid Mainly composed of (meth) acrylic resin obtained by homo- or copolymerization of (meth) acrylic monomers such as cyclohexyl, ethylhexyl acrylate, methacrylic acid, acrylic acid, acrylonitrile, methacrylonitrile, or the above (meth) acrylates. If necessary, a monomer having a polymerizable double bond that can be copolymerized therewith, such as ethylene, butadiene, isoprene, vinyl acetate, vinyl propionate, vinyl butyrate, styrene, α-methylstyrene, vinyl Rutoruen, divinyl benzene, N- cyclohexyl maleimide, N- ethylmaleimide, N- phenylmaleimide, and the like is added, (meth) acrylic resin as a copolymer component.
The (meth) acrylic resin can be obtained by polymerizing the (meth) acrylic monomer or a monomer having a polymerizable double bond by a conventional method.

As a method for introducing a polymerizable unsaturated group into the (meth) acrylic resin, for example, a carboxyl group-containing polymerizable monomer such as acrylic acid or methacrylic acid, dimethylaminoethyl methacrylate, An amino group-containing polymerizable monomer such as dimethylaminopropylacrylamide is blended and copolymerized to obtain the copolymer having a carboxyl group or an amino group, and then the carboxyl group or amino group and glycidyl such as glycidyl methacrylate. A method of reacting a monomer having a group and a polymerizable unsaturated group,
A hydroxyl group-containing monomer such as 2-hydroxyethyl methacrylate or 2-hydroxyethyl acrylate is previously blended and copolymerized as the copolymer component to obtain the copolymer having a hydroxyl group. Next, the hydroxyl group and isocyanate ethyl methacrylate are obtained. A method of reacting a monomer having a polymerizable unsaturated group with an isocyanate group such as
A glycidyl group-containing polymerizable monomer such as glycidyl methacrylate is previously blended and copolymerized as the copolymer component to obtain the copolymer having a glycidyl group, and then the glycidyl group and a carboxyl group of acrylic acid or methacrylic acid. A method of reacting the containing polymerizable monomer,
During polymerization, thioglycolic acid is used as a chain transfer agent to introduce a carboxyl group at the end of the copolymer, and a monomer having a glycidyl group such as glycidyl methacrylate and a polymerizable unsaturated group is added to the carboxyl group. How to react,
As a polymerization initiator, a carboxyl group-containing azo initiator such as azobiscyanopentanoic acid is used to introduce a carboxyl group into the copolymer, and the carboxyl group has a glycidyl group such as glycidyl methacrylate and a polymerizable unsaturated group. Examples include a method of reacting monomers.
Among them, a carboxyl group-containing monomer such as acrylic acid or methacrylic acid or an amino group-containing monomer such as dimethylaminoethyl methacrylate or dimethylaminopropylacrylamide is copolymerized, and the carboxyl group or amino group and glycidyl methacrylate, etc. Or a monomer having a polymerizable unsaturated group, or a glycidyl group-containing polymerizable monomer such as glycidyl methacrylate in advance as a copolymerization component and copolymerized to have a glycidyl group The method of obtaining the copolymer and then reacting the glycidyl group with a carboxyl group-containing polymerizable monomer of acrylic acid or methacrylic acid is the simplest and preferred.

  The (meth) acrylic resin having a radically polymerizable unsaturated group is preferably contained in an amount of 10 to 99.9% by weight based on the total solid content of the radically polymerizable resin composition, and is in the range of 40 to 99.9% by weight. Most preferred. If it is less than 10%, tackiness may remain on the surface due to the addition of polyalkylene glycol (meth) acrylate that is liquid at room temperature.

(Other components Photopolymerization initiator)
When the thermal transfer film of the present invention is cured with active energy rays, a photopolymerization initiator may be preferably used in the radical polymerizable resin composition layer. Examples of photopolymerization initiators include, for example, acetophenone compounds such as diethoxyacetophenone and 1-hydroxycyclohexyl-phenyl ketone; benzoin compounds such as benzoin and benzoin isopropyl ether; 2,4,6-trimethylbenzoin diphenylphosphine oxide Acylphosphine oxide compounds such as benzophenone, o-benzoylbenzoic acid methyl-4-phenylbenzophenone and other benzophenone compounds; 2,4-dimethylthioxanthone and other thioxanthone compounds; 4,4′-diethylaminobenzophenone and other aminobenzophenones Compounds such as polyether-based maleimide carboxylic acid ester compounds, and the like, which can be used in combination. The usage-amount of a photoinitiator is 0.1-20 mass% with respect to the total amount of solid content of a radically polymerizable resin composition, Preferably it is 0.5-15 mass%. Examples of the photosensitizer include amines such as triethanolamine and ethyl 4-dimethylaminobenzoate. Furthermore, onium salts such as benzylsulfonium salt, benzylpyridinium salt, and arylsulfonium salt are known as photocationic initiators, and these initiators can also be used, and are used in combination with the above photopolymerization initiators. You can also.

(Thermal polymerization initiator)
Moreover, when thermosetting the film for thermal transfer of the present invention, a thermal polymerization initiator may be preferably used for the radical polymerizable resin composition layer. Examples of thermal polymerization initiators include various peroxides such as hydrogen peroxide, t-butyl hydroperoxide, di-t-butyl peroxide, cumene hydroperoxide; potassium persulfate, sodium persulfate, ammonium persulfate, etc. Various persulfates of azobisisobutyronitrile, 1-[(1-cyano-1-methylethyl) azo] formamide, 2,2′-azobis [2- (5-methyl-2-imidazoline-2) -Yl) propane] dihydrochloride, 2,2′-azobis [2- (2-imidazolin-2-yl) propane] or its dihydrochloride, 2,2′-azobis [2- (4,5,5) Dihydrochloride of 6,7-tetrahydro-1H-1,3-diazepin-2-yl) propane], 2,2′-azobis [N- (4-aminophenyl) -2-methylpropion Amidine], dihydrochloride of 2,2′-azobis (2-methylpropionamide) and the like, and various azo initiators. In particular, in the case of the vacuum forming method, a sufficient amount of heat is applied to the film to form it instantaneously, so that a thermal polymerization initiator can also be suitably used.

(Isocyanate compound)
Moreover, when thermosetting the film for thermal transfer of the present invention, a resin having a hydroxyl group is selected as the (meth) acrylic resin having a radical polymerizable unsaturated group, and a divalent or higher isocyanate compound is added. A urethane cross-linked structure different from the cross-linked structure derived from radically polymerizable unsaturated groups can be introduced, which is preferable.
As the (meth) acrylic resin having a radical polymerizable unsaturated group and a hydroxyl group, for example, a carboxyl group-containing monomer such as acrylic acid or methacrylic acid is copolymerized, and the carboxyl group and glycidyl are copolymerized. A method of reacting a monomer having a polymerizable unsaturated group with a glycidyl group such as methacrylate, or a glycidyl group-containing polymerizable monomer such as glycidyl methacrylate in advance as a copolymerization component and copolymerizing the glycidyl group (Meth) acrylic resin obtained by a method of reacting a glycidyl group with a carboxyl group-containing polymerizable monomer of acrylic acid or methacrylic acid, or hydroxyethyl acrylate, etc. Examples include (meth) acrylic resins obtained by copolymerizing (meth) acrylates having a hydroxyl group.
When making it react with the hydroxyl group which the (meth) acryl resin which has a divalent or more valent isocyanate compound and a radically polymerizable unsaturated group has, it is preferable to make it react with a part of hydroxy group which this resin has. In this case, it is preferable to react 5 to 50% of the hydroxy group of the resin, more preferably 10 to 40%, and particularly preferably 15 to 30%.

  Examples of the isocyanate compound include aromatic diisocyanates such as tolylene diisocyanate and diphenylmethane-4,4′-diisocyanate, meta-xylylene diisocyanate, α, α, α ′, α′-tetramethyl-meta-xylylene diisocyanate. Polyisocyanates mainly composed of aralkyl diisocyanates such as tetramethylene diisocyanate, 1,5-pentamethylene diisocyanate, 1,6-hexamethylene diisocyanate, 2,2,4- (or 2,4,4-trimethyl- 1,6-hexamethylene diisocyanate, lysine isocyanate, isophorone diisocyanate, hydrogenated xylene diisocyanate, hydrogenated diphenylmethane diisocyanate, 1,4-diisocyanate cyclohexane, 1,3- (Diisocyanatemethyl) cyclohexane, aliphatic diisocyanates such as 4,4′-dicyclohexylmethane diisocyanate, allophanate type polyisocyanates, biuret type polyisocyanates, adduct type polyisocyanates and isocyanurates which are aliphatic polyisocyanates obtained from aliphatic diisocyanates Type polyisocyanate, and any of them can be suitably used.

  In addition, as the above-described polyisocyanate, so-called blocked polyisocyanate compounds blocked with various blocking agents can be used. Examples of the blocking agent include alcohols such as methanol, ethanol and lactic acid esters; phenolic hydroxyl group-containing compounds such as phenol and salicylic acid ester; amides such as ε-caprolactam and 2-pyrrolidone; oximes such as acetone oxime and methyl ethyl ketoxime Active methylene compounds such as methyl acetoacetate, ethyl acetoacetate and acetylacetone can be used. By using the block polyisocyanate compound, it becomes possible to use a hydroxyl group-containing solvent such as alcohol for the coating material for forming the radical polymerizable resin composition layer described later.

(Other ingredients)
Moreover, an inorganic or metal compound, organic fine particles, etc. can also be added to a radically polymerizable resin composition layer. Examples of the inorganic or metal compound include silica, silica gel, silica sol, silicone, montmorillonite, mica, alumina, titanium oxide, talc, barium sulfate, aluminum stearate, magnesium carbonate, glass beads and the like. Further, organosilica sol, acrylic-modified silica, closite, etc. obtained by organically treating the inorganic or metal compound may be used. Examples of the organic fine particles include fine particles such as polyethylene resin, acrylic resin, styrene resin, fluorine resin, melamine resin, polyurethane resin, polycarbonate resin, and phenol resin. These may be used alone or in combination. In addition, a general-purpose additive such as an ultraviolet absorber, a leveling agent, an antiblocking agent and the like can be added within a range not impairing the effects of the present invention.

  The thickness of the radical polymerizable resin composition layer used in the present invention is preferably 1 to 50 μm, more preferably 3 to 40 μm, from the viewpoint of surface protection of the substrate to be transferred or the injection-molded product and coating properties.

(Decoration layer)
A general-purpose printing ink or paint can be used for the decorative layer, and can be formed using gravure printing, offset printing, screen printing, inkjet printing, thermal transfer printing, and the like. It is preferable that the dry film thickness of a decoration layer is 0.5-15 micrometers, More preferably, it is 1-7 micrometers. A colored layer having no pattern and a colorless varnish resin layer can also be formed by coating.
In addition, the printing pattern for printing can be any printing pattern as long as it can cause a plate or can be printed. A solid version may also be used.

As a coloring material used for printing ink or paint, printing can be performed using a known organic pigment or inorganic pigment, which is preferable.
Examples of the organic pigment include quinacridone pigments, phthalocyanine pigments, selenium pigments, perylene pigments, phthalone pigments, dioxazine pigments, isoindolinone pigments, methine / azomethine pigments, and diketopyrrolopyrrole pigments. Azo lake pigments, insoluble azo pigments, condensed azo pigments, and the like.
Examples of inorganic pigments include inorganic pigments such as carbon black, iron oxide and titanium oxide, metal powder pigments such as aluminum powder and bronze powder, and pearlescent pigments such as titanium oxide-coated mica.

  The resin for varnish contained in the ink is not particularly limited. For example, acrylic resin, polyurethane resin, polyester resin, vinyl resin (vinyl chloride, vinyl acetate, vinyl chloride-vinyl acetate copolymer resin), chlorine Known inks such as olefinic olefin resin, ethylene-acrylic resin, petroleum resin, and cellulose derivative resin can be used.

  Further, the organic solvent contained in the ink can be used without particular limitation as long as it does not attack the curable resin layer or the peelable film described later. Specific examples include, for example, toluene, xylene, cyclohexane, n-hexane or Hydrocarbon organic solvents such as mineral spirits, ester organic solvents such as methyl acetate, ethyl acetate, n-butyl acetate, isobutyl acetate, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, diethylene glycol monobutyl ether acetate or amyl acetate, Ether organic solvents such as n-butyl ether, dioxane, ethylene glycol monomethyl ether, ethylene glycol monobutyl ether or diethylene glycol, acetone, methyl ethyl Ketone, organic solvents such as methyl isobutyl ketone, methyl amino ketone, diisobutyl ketone or cyclohexanone, nitrogen-containing systems such as N-methylpyrrolidone, “Swazole 310, Swazole 1000, Swazol 1500” [manufactured by Cosmo Oil Co., Ltd.], etc. And aromatic petroleum solvent systems. These organic solvents may be used alone or in combination of two or more.

  In addition to the base resin and the colorant, the printing ink or paint may contain a plasticizer, a surfactant, an antioxidant, an ultraviolet absorber, a matting agent, a solvent, and the like as necessary.

(Method for producing thermal transfer film)
The film for thermal transfer of the present invention is most preferably a method in which a decorative layer is directly printed or coated on a support film provided with the radical polymerizable resin layer. Further, an intermediate (primer) layer may be provided in order to ensure interlayer adhesion between the radical polymerizable resin layer and the decorative layer.
The method for providing the radical polymerizable resin composition layer on the support film or the method for providing the decorative layer is not particularly limited. For example, a gravure printing method, an offset printing method, a gravure offset printing method, a flexographic printing method. , Various printing methods such as screen printing method, gravure coating method, micro gravure coating method, roll coating method, rod coating method, kiss coating method, knife coating method, air knife coating method, comma coating method, die coating method, lip coating method Various known coating methods such as a flow coating method, a dip coating method, and a spray coating method can be appropriately used. In particular, the decoration layer can be formed by gravure printing, offset printing, screen printing, ink jet printing, and the like, and gravure printing is preferable because a high-quality image can be easily obtained. It is preferable that the dry film thickness of a decoration layer is 0.5-15 micrometers, More preferably, it is 1-7 micrometers.

Further, by dry lamination (dry lamination method), the support film provided with the radical polymerizable resin composition layer and the optional peelable film provided with the decoration layer are combined with the polymerizable resin layer and the decorative layer. Can be manufactured by a method in which they are stacked so as to face each other and bonded together by dry lamination (dry lamination method) and transferred.
The bonding temperature by drying and heating and pressing is not particularly limited, and may be performed while taking into consideration the heat-resistant temperature of the substrate film to be used.

  The manufactured thermal transfer film may be aged as necessary, for example, to improve interlayer adhesion.

(Film thickness for thermal transfer)
The total film thickness of the thermal transfer film of the present application is not particularly limited because it depends on the thermal transfer method, but is preferably 21.5 to 200 μm, more preferably 30 to 150 μm from the viewpoint of the shape following property to the transfer substrate.

(Adhesive layer)
In addition, an arbitrary layer can be further laminated as long as the effects of the present invention are not impaired. For example, when the thermal transfer film of the present invention is affixed to a substrate to be transferred, it is preferable to provide an adhesive layer or an adhesive layer on the surface of the decorative layer that contacts the substrate to be transferred. The adhesive layer or the pressure-sensitive adhesive layer is a layer provided for the purpose of increasing the adhesive force with the adherend, and may be an adhesive or a pressure-sensitive adhesive, and appropriately select a material that adheres to the resin film and the adherend. Is possible.

  For example, as an adhesive, for example, acrylic resin, urethane resin, urethane-modified polyester resin, polyester resin, epoxy resin, ethylene-vinyl acetate copolymer resin (EVA), vinyl chloride resin, vinyl chloride-vinyl acetate copolymer resin, natural Examples thereof include synthetic rubbers such as rubber, SBR, NBR, and silicone rubber. Solvent type or solventless type can be used.

  The pressure-sensitive adhesive is not particularly limited as long as it has tackiness at the temperature at which it is thermoformed. Type adhesive, acrylic emulsion resin, styrene butadiene latex resin, natural rubber latex resin, styrene-isoprene copolymer resin, styrene-butadiene copolymer resin, styrene-ethylene-butylene copolymer resin, ethylene-vinyl acetate resin Solvent-free pressure-sensitive adhesives such as polyvinyl alcohol, polyacrylamide, and polyvinyl methyl ether.

  When the adhesive layer or the pressure-sensitive adhesive layer is provided on the thermal transfer film of the present invention, it is directly printed or coated on the film provided with the radical polymerizable resin composition layer and the decorative layer, or the radical polymerizable resin composition. It can be obtained by a method in which the layer and the decorative layer are stacked so as to face each other and transferred by dry lamination. In the latter case, it is preferable to transfer the decorative layer having an adhesive layer, but the adhesive layer may be provided after the decorative layer is transferred.

(Thermal transfer method)
The thermal transfer film of the present invention can be used in a known transfer method. Specifically, if necessary, a pre-molded thermal transfer film is placed on the surface of the female mold, both molds are closed, and a molten resin is injected from the injection hole into the cavity (molded cavity) between the two molds. After the mold is cooled and solidified, both molds are opened, the molded product and the transfer film adhered thereto are taken out of the mold, only the base film is peeled off, and the decorative product in which the transfer layer is transferred and formed on the substrate to be transferred The injection transfer simultaneous transfer method or a heat transfer film placed above the molded substrate to be transferred, the transfer layer facing the substrate to be transferred and the film heated to the softening temperature or higher, and then vacuum Underneath the transfer film during thermal transfer, such as vacuum molding simultaneous pasting method or lapping simultaneous transfer method, etc. Mold transfer method to three-dimensional shape with elongation and deformation Particularly preferably it is possible to use a thermal transfer film of the present invention. However, the transfer film of the present invention may be used for a transfer method such as hot stamping which extends on the transfer film and does not undergo deformation.

(Active energy ray irradiation)
The radical polymerizable resin composition layer of the decorative product to which the film for thermal transfer of the present invention is transferred is cured with active energy rays or the like. As the active energy ray, it is usually preferable to use visible light or ultraviolet light. In particular, ultraviolet rays are suitable. As the ultraviolet light source, sunlight, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, or the like is used. In addition, as a heating source when heat is used in combination, a known heat source such as hot air or near infrared light can be applied.
The irradiation dose at this time is preferably such that the curable resin layer is completely cured, and specifically, a range of 250 mJ / cm ^{2 to} 3000 mJ / cm ² is preferable. In particular, 1000 mJ / cm ^{2 to} 3000 mJ / cm in order to sufficiently cure the radical-reactive diluent or radical-polymerizable oligomer that has moved to the interface with the decorative layer and improve the adhesion to the substrate to be transferred. A range of ² is more preferred. The timing at which the substrate film is peeled may be before or after the irradiation with the active energy ray.

(Transfer substrate)
The substrate to which the thermal transfer film of the present invention can be transferred is not particularly limited, and various shapes such as resin, metal, glass, wood, and paper can be used, and the shapes are painted, plated, scratched, and the like. It may be decorated by the regular decoration method.
Further, when the material of the adherend surface of the substrate to be transferred and the material of the thermoplastic resin or ink binder used in the thermal transfer film of the present invention are materials that can be thermally bonded or heat-bonded, it is more closely attached Excellent in properties and preferable. For example, when the material of the adherend surface of the substrate to be transferred is an acrylic resin or a styrene resin, the thermoplastic resin used for the thermal transfer film is preferably an acrylic resin.

  Hereinafter, the present invention will be described with reference to examples. Unless otherwise specified, “parts” and “%” are based on weight.

(Evaluation method)
<Adhesion>
Adhesiveness was evaluated by a peel test of cross-cut cello tape (cello tape is a registered trademark) of JIS K-5400. Since PC / ABS resin was used as the substrate, the evaluation was performed at 2 mm square and 100 squares. The case where the number of remaining cells was 100 was evaluated as ◯, the case where 100 cells remained but there were not more than 10 cells was determined as Δ, and the others were determined as ×.

<Fingerprint visibility>
After 10 μL of oleic acid is dropped on a Teflon sheet (Teflon is a registered trademark) and wiped off with a urethane sponge (3M Scotch Bright) cut into 3 cm square, the surface of the sponge with oleic acid attached is removed. The surface of the product to be evaluated was pressed for 10 seconds to adhere oleic acid.
By using a color difference meter to calculate dL * before and after oleic acid adhesion, it is used as a substitute characteristic value of visibility when a fingerprint is adhered, dL * ≦ 1.5 is ○, 1.5 <dL * ≦ 3 is Δ and 3 <dL * were evaluated as x.

<Fingerprint wiping>
In the same way as the evaluation of fingerprint visibility, oleic acid was attached and then wiped twice with absorbent cotton (each using a new surface). The color difference meter was used to recover from dL * before and after oleic acid attachment. By calculating the rate, a substitute characteristic value for the fingerprint wiping property was obtained. 80% ≦ dL * (recovery rate) was evaluated as ○, 50% ≦ dL * (recovery rate) <80% as Δ, and dL * (recovery rate) <50% as ×.

<Vividness>
The surface gloss value (60 °) of the molded product was measured according to JIS Z8741 using “Micro-TRI-gloss” manufactured by BYK Gardner, and the difference from the standard gloss value (prescription without addition of polyalkylene glycol (meth) acrylate) (Reference gloss value-measured value) was evaluated as ○ when less than 1%, Δ when 1% or more and less than 3%, and × when 3% or more.

(Method for producing (meth) acrylic resin having radically polymerizable unsaturated group)
<Reference Example 1>
A four-necked flask equipped with a thermometer, a stirrer, a reflux condenser and a nitrogen gas inlet tube was charged with 950 parts of butyl acetate and heated to 80 ° C. When the same temperature was reached, 970 parts of butyl acrylate, methacrylate A mixture comprising 30 parts of acid and 7 parts of 2,2′-azobis (2-methylbutyronitrile) was added dropwise over 4 hours. After completion of the addition, the temperature was raised to 90 ° C. and maintained for 10 hours to continue the reaction. .
The temperature of the reaction solution was lowered to 50 ° C., a solution in which 0.2 part of t-butylpyrocatechol was dissolved in 20 parts of butyl acetate was added, 20 parts of glycidyl methacrylate and 3 parts of dimethylaminoethanol were further added, and then up to 80 ° C. The solution was heated and reacted at the same temperature for 10 hours to obtain a solution of a (meth) acrylic resin (A1) having a radical polymerizable unsaturated group.

(Molding method)
<Injection molding method>
The film for thermal transfer obtained by the method described later was placed on an injection molding machine “EC75N-1.5Y” manufactured by Toshiba Machine Co., and then the mold was closed. The mold has a tray shape in which the shape of the injection-molded body is 100 (L) × 100 (W) × 9 (H) mm, corner R = 10 mm, rising portion R = 5R, draft angle 18.5 °. I used something.
The mold was heated to 50 ° C. with a heater, and Teijin Chemicals' injection resin “Multilon TN-3715B” was injected at an injection resin temperature of 265 ° C. The injection molded body was removed from the mold, the peelable film was peeled off, and an injection molded body on which the radical polymerizable resin composition layer and the decorative layer of the thermal transfer film were transferred was obtained. Then, a decorative molded body was obtained by performing ultraviolet irradiation with a total irradiation amount of 1000 mJ / cm ² (peak intensity 180 mW / cm 2).

<Examples 1-8 Manufacturing Method of Thermal Transfer Film>
Polyalkylene glycol (meth) acrylate (manufactured by NOF Corporation) A1 to A8 shown in Table 1 with respect to the nonvolatile content of the solution of the (meth) acrylic resin having a radical polymerizable unsaturated group obtained in Reference Example 1 5% by weight and 1% by weight of a photopolymerization initiator Irgacure 184 (manufactured by Ciba Specialty) were added to prepare a radical polymerizable resin composition.
The radical polymerizable resin composition is applied onto a polyethylene terephthalate (PET) sheet “Therapy HP2 / TB (S)” (film thickness 50 μm) manufactured by Toray Film Processing Co., Ltd. using a rod gravure coater, and dried for 100 μm for 1 minute. Thus, a film having a radically polymerizable resin composition layer having a film thickness of 5 μm after drying was obtained.
The film for thermal transfer was obtained by giving an aluminum hairline pattern directly to a radically polymerizable resin composition layer with a gravure printing machine using DIC-made XS-756IM ink.

The obtained thermal transfer film was subjected to the injection molding method to obtain an injection molded body having a pattern. The obtained injection-molded product had a performance in which fingerprints were difficult to see and easy to wipe off. The results are shown in Table 1-1.
<Example 9 Production Method for Thermal Transfer Film>
5 weight of polyalkylene glycol (meth) acrylate (made by NOF Corporation) A5 shown in Table 1 with respect to the non volatile matter of the solution of the (meth) acrylic resin which has the radically polymerizable unsaturated group obtained in Reference Example 1. % And a photopolymerization initiator Irgacure 184 (manufactured by Ciba Specialty) were added to prepare a radical polymerizable resin composition.
On a polyethylene terephthalate (PET) sheet “Therapy HP2 / TB (S)” (film thickness 50 μm) manufactured by Toray Film Processing Co., Ltd., with the surface provided with irregularities on the surface by a scratch method using a rod gravure coater. And dried at 100 ° C. for 1 minute to obtain a film having a radically polymerizable resin composition layer having a film thickness of 5 μm after drying.
A film for thermal transfer was obtained by directly applying aluminum tone solid printing to the radical polymerizable resin composition layer with a gravure printing machine using DIC-made XS-756IM ink.

The obtained thermal transfer film was subjected to the injection molding method to obtain an injection-molded body having hairline-like irregularities (scratch method). The obtained injection-molded product had a performance in which fingerprints were difficult to see and easy to wipe off. The results are shown in Table 1-2.

<Example 10 Production Method for Thermal Transfer Film>
5 weight of polyalkylene glycol (meth) acrylate (made by NOF Corporation) A6 shown in Table 1 with respect to the non volatile matter of the solution of the (meth) acrylic resin which has the radically polymerizable unsaturated group obtained in Reference Example 1. % And photopolymerization initiator Irgacure 184 (manufactured by Ciba Specialty) 1% by weight, isocyanate compound Vernock DN-981 (manufactured by DIC) 24% (based on the hydroxyl group contained in the (meth) acrylic resin having a radical polymerizable unsaturated group) (As an equivalent ratio) was added to prepare a radical polymerizable resin composition.
On a polyethylene terephthalate (PET) sheet “Therapy HP2 / TB (S)” (film thickness 50 μm) manufactured by Toray Film Processing Co., Ltd., with the surface provided with irregularities on the surface by a scratch method using a rod gravure coater. And dried at 100 ° C. for 1 minute to obtain a film having a radically polymerizable resin composition layer having a film thickness of 5 μm after drying.
A film for thermal transfer was obtained by directly applying aluminum tone solid printing to the radical polymerizable resin composition layer with a gravure printing machine using DIC-made XS-756IM ink.

  From the obtained film for thermal transfer, an injection-molded article having hairline-like irregularities was obtained according to the injection molding method. The obtained injection-molded product had a performance in which fingerprints were difficult to see and easy to wipe off. The results are shown in Table 1-2.

Abbreviations in Table 1-1 and Table 1-2 are as follows.
A1: Polyethylene glycol dimethacrylate A2: Polypropylene glycol dimethacrylate A3: Polypropylene glycol diacrylate A4: Polypropylene glycol monomethacrylate A5: Polypropylene glycol dimethacrylate A6: Polytetramethylene glycol dimethacrylate A7: Polyethylene glycol dimethacrylate A8: Polypropylene glycol dimethacrylate PEG; polyethylene glycol PPG; polypropylene glycol PTMG; polytetramethylene glycol

<Comparative Example 1 An example of an injection molded article using a thermal transfer film that does not contain polyalkylene glycol (meth) acrylate>
10% by weight of a photopolymerization initiator Irgacure 184 (manufactured by Ciba Specialty) is added to the nonvolatile content of the solution of the (meth) acrylic resin having a polymerizable unsaturated group obtained in Reference Example 1, and a radical polymerizable resin A composition was prepared.
The radical polymerizable resin composition was applied onto a polyethylene terephthalate (PET) sheet “Therapy HP2 / TB (S)” (film thickness 50 μm) manufactured by Toray Film Processing Co., Ltd. using a rod gravure coater and dried at 100 ° C. for 1 minute. Thus, a film having a radically polymerizable resin composition layer having a film thickness of 5 μm after drying was obtained.
The film for thermal transfer was obtained by giving an aluminum hairline pattern directly to a radically polymerizable resin composition layer with a gravure printing machine using DIC-made XS-756IM ink.
Using the obtained thermal transfer film, an injection-molded article having a pattern was obtained according to the injection molding method. The obtained injection-molded product was easy to see fingerprints and difficult to wipe off. The results are shown in Table 2.

<Comparative Examples 2 and 3> Examples of injection molded articles using a thermal transfer film containing alkylene (meth) acrylate>
5% by weight of (meth) acrylate (manufactured by Sartomer) having a stearic chain or a tridecine chain based on the nonvolatile content of the solution of the (meth) acrylic resin having a radical polymerizable unsaturated group obtained in Reference Example 1. A photopolymerization initiator Irgacure 184 (manufactured by Ciba Specialty) was added to prepare a radical polymerizable resin composition.
The radical polymerizable resin composition was applied onto a polyethylene terephthalate (PET) sheet “Therapy HP2 / TB (S)” (film thickness 50 μm) manufactured by Toray Film Processing Co., Ltd. using a rod gravure coater and dried at 100 ° C. for 1 minute. Thus, a film having a radically polymerizable resin composition layer having a film thickness of 5 μm after drying was obtained.
The film for thermal transfer was obtained by giving an aluminum hairline pattern directly to a radically polymerizable resin composition layer with a gravure printing machine using DIC-made XS-756IM ink.
The obtained thermal transfer film was obtained according to the injection molding method to obtain an injection-molded body having a pattern, but the fingerprint visibility was improved, but the wiping property was inferior. This is presumed to be difficult to wipe off due to the affinity between the alkylene (meth) acrylate introduced as an additive and the fingerprint. The results are shown in Table 2.

<Comparative example 4> Example of injection molded article using thermal transfer film containing fluorine-based additive>
2 wt% fluorine-containing UV curable resin “Megafac RS-75” (manufactured by DIC) (A10) based on the nonvolatile content of the solution of the (meth) acrylic resin having a polymerizable unsaturated group obtained in Reference Example 1 ) And 10% by weight of a photopolymerization initiator Irgacure 184 (manufactured by Ciba Specialty) to prepare a radical polymerizable resin composition.
The radical polymerizable resin composition was applied onto a polyethylene terephthalate (PET) sheet “Therapy HP2 / TB (S)” (film thickness 50 μm) manufactured by Toray Film Processing Co., Ltd. using a rod gravure coater and dried at 100 ° C. for 1 minute. Thus, a film having a radically polymerizable resin composition layer having a film thickness of 5 μm after drying was obtained.
The film for thermal transfer was obtained by giving an aluminum hairline pattern directly to a radically polymerizable resin composition layer with a gravure printing machine using DIC-made XS-756IM ink. At this time, the printability of the hairline pattern was slightly poor, and each dot was small, and the concealability was lowered.
Using the obtained thermal transfer film, an injection-molded article having a pattern was obtained according to the injection molding method. The obtained injection-molded product was inferior in terms of adhesion, although the fingerprint visibility and wiping property were slightly improved. This is presumed that the fluorine-containing additive was segregated at the air interface during coating, resulting in poor adhesion. The results are shown in Table 2.

<Comparative example 5> Example of injection molded article using thermal transfer film containing fine particles of Teflon>
2% by weight of Teflon fine particles “KTL-4N” (made by Kitamura) (A11) and 10% by weight of the nonvolatile content of the solution of the polymerizable unsaturated group-containing (meth) acrylic resin obtained in Reference Example 1 A photopolymerization initiator Irgacure 184 (manufactured by Ciba Specialty) was added to prepare a radical polymerizable resin composition.
The radical polymerizable resin composition is applied onto a polyethylene terephthalate (PET) sheet “Therapy HP2 / TB (S)” (film thickness 50 μm) manufactured by Toray Film Processing Co., Ltd. using a rod gravure coater and dried at 100 ° C. for 1 minute. Thus, a film having a radically polymerizable resin composition layer having a film thickness of 5 μm after drying was obtained.
The film for thermal transfer was obtained by giving an aluminum hairline pattern directly to a radically polymerizable resin composition layer with a gravure printing machine using DIC-made XS-756IM ink. At this time, the printability of the hairline pattern was slightly poor and some of the colors were missing.
Using the obtained thermal transfer film, an injection-molded article having a pattern was obtained according to the injection molding method. The obtained injection-molded product was inferior in fingerprint wiping, although the fingerprint visibility was slightly improved. The results are shown in Table 2.

Abbreviations in Table 2 are as follows.
A8: Stearic monoacrylate A9: Tridecine monoacrylate A10: Fluorine-containing UV curable resin “Megafac RS-75”
A10: Teflon fine particles "KTL-4N"

As a result, the films for thermal transfer obtained in Examples 1 to 8 all showed the performance that it was difficult to see the fingerprints and were easy to wipe off.
On the other hand, the thermal transfer films obtained in Comparative Examples 1 to 5 were not obtained with the performance satisfying all of the fingerprint visibility, the fingerprint wiping property, and the sharpness.

Claims (6)

  A thermal transfer film having a transfer layer in which a radical polymerizable resin composition layer and a decorative layer are laminated in this order on a base film, wherein the radical polymerizable resin composition layer is a radical polymerizable unsaturated group A film for thermal transfer comprising a (meth) acrylic resin having a polyalkylene glycol chain and a compound having one or more (meth) acryloyl groups. The (meth) acrylic resin having a radically polymerizable unsaturated group is a polymer of a monomer component containing a (meth) acrylic monomer , and is a (meth) acrylic resin into which a radically polymerizable unsaturated group has been introduced. The thermal transfer film according to claim 1.   The film for thermal transfer according to claim 1 or 2, wherein the compound having the polyalkylene glycol chain and one or more (meth) acryloyl groups is polyalkylene glycol mono (meth) acrylate or polyalkylene glycol di (meth) acrylate.   The thermal transfer film according to claim 1, wherein the (meth) acrylic resin having a radically polymerizable unsaturated group further has a hydroxy group. The thermal transfer film according to claim 4, wherein the isocyanate compound is reacted with a part of a hydroxy group of the (meth) acrylic resin containing a divalent or higher isocyanate compound and having the radically polymerizable unsaturated group. A method for producing a decorative molded product , comprising mounting the film for thermal transfer according to any one of claims 1 to 5 in an injection mold and performing injection molding.