Film having cured layer of photocurable resin composition

Abstract

To provide a film which has good moldability, is hardly scratched by a nail, and can be self-repaired with time even when scratched.SOLUTION: The film has a cured layer of a photocurable resin composition on a plastic substrate, wherein the photocurable resin composition contains a polyfunctional urethane (meth) acrylate having a polycarbonate skeleton, a silicone-based leveling agent and a photopolymerization initiator, and the leveling agent contains a polyether-modified polysiloxane.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a film having a cured layer of a photocurable resin composition that is cured by ultraviolet light or the like. [Background technology]

[0002] Acrylic photocurable resins are used in many fields to impart special properties to the surfaces of plastic films and plastic moldings. For example, hard coat (hereinafter referred to as HC) films, which are applied to PET (polyethylene terephthalate) films to impart high hardness, are used in large quantities as films for touch panels and moldings.

[0003] Among these, insert molding films are well known for their molding applications. A design is printed on the film surface, and the film is then softened by heating and molded into a three-dimensional shape. However, hardening the HC resin layer applied to the film makes it prone to microcracks on the curved surface when processed into a three-dimensional shape, limiting the shape that can be processed. For this reason, the applicant previously invented a composition for molding HC resin, containing a urethane acrylate reacted with specific components, a light stabilizer, and a fluorine-based silicone compound with reactive functional groups (Patent Document 1). This composition was an excellent HC agent that exhibited good moldability and weather resistance in addition to scratch resistance and chemical resistance.

[0004] By selecting the right HC agent for these molding applications, the applications of film molding, such as insert molding, have expanded dramatically. Meanwhile, in pursuit of greater processability, there is a strong demand for improved formability and scratch resistance, and there is an increasing demand for self-healing properties, meaning that scratches will heal over time, as a concept for providing excellent scratch resistance. Given this background, there has been a demand for films that can be used in molding applications that have excellent formability, are scratch-resistant, and can self-heal over time even if scratches do occur. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 7293518 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present invention is to provide a film that has good formability, is resistant to scratches by fingernails, and is capable of self-repairing over time even if scratched. [Means for solving the problem]

[0007] In order to solve the above problems, the invention of claim 1 provides a film having a cured layer of a photocurable resin composition on a plastic substrate, wherein the photocurable resin composition contains a polyfunctional urethane (meth)acrylate (A) having a polycarbonate skeleton, a silicone-based leveling agent (B), and a photopolymerization initiator (C), and (B) contains a polyether-modified polysiloxane.

[0008] The invention of claim 2 provides the film according to claim 1, characterized in that the polyfunctional urethane (meth)acrylate (A) is a polyfunctional urethane (meth)acrylate obtained by reacting a polycarbonate polyol (a1) with a polyisocyanate (a2) to produce a polyisocyanate, and then further reacting the polyisocyanate with a hydroxyl group-containing (meth)acrylate (a3).

[0009] The invention of claim 3 provides the film according to claim 1, characterized in that the photopolymerization initiator (C) contains an α-hydroxyacetophenone-based compound.

[0010] A fourth aspect of the present invention provides the film according to the first aspect, wherein the plastic substrate is a composite substrate of polycarbonate and acrylic.

[0011] The invention of claim 5 provides the film according to any one of claims 1 to 4, which is used for film molding. [Effects of the Invention]

[0012] The film of the present invention has good formability, is scratch-resistant, and has the ability to self-repair over time even if scratched, making it useful as a film for use in molding applications such as insert molding. BEST MODE FOR CARRYING OUT THE INVENTION

[0013] The photocurable resin composition (hereinafter referred to as the present resin composition) that forms the cured layer of the film of the present invention contains a polyfunctional urethane (meth)acrylate (A), a silicone-based leveling agent (B), and a photopolymerization initiator (C). In this specification, the term "(meth)acrylate" encompasses both acrylate and methacrylate.

[0014] The polyfunctional urethane (meth)acrylate (A) used in the present resin composition is a urethane (meth)acrylate having a polycarbonate skeleton and multiple functional groups. Due to the high cohesive strength of the polycarbonate skeleton, it has excellent hydrolysis resistance, heat resistance, weather resistance, oil resistance, and self-healing properties (elastic recovery). For example, it can be synthesized by reacting a polycarbonate polyol (a1) with a polyisocyanate (a2), and then further reacting the resulting polyisocyanate with a hydroxyl group-containing (meth)acrylate (a3). The number of functional groups is preferably 2 to 8, more preferably 2 to 6, and particularly preferably 2 to 4. By setting the number of functional groups within this range, the elongation of the cured film can be increased, enabling the formation of a film that balances good moldability and excellent scratch resistance due to self-healing properties.

[0015] The (a1) is a compound having a carbonate skeleton and multiple hydroxyl groups, and can be produced, for example, by reacting a dihydric alcohol with a carbonate ester or phosgene. The general formula is, but is not limited to, the following chemical formula (1). Chemical formula (1) JPEG2026018122000001.jpg36135 (In the formula, R1 and R2 are each independently or identically a hydrocarbon group or a substituted hydrocarbon group, and n is an integer of 1 or greater. Examples of the hydrocarbon group include an acyclic aliphatic group, a cyclic aliphatic group, an aromatic group, or a combination thereof. The substituent of the substituted hydrocarbon group may contain atoms other than carbon and hydrogen atoms.)

[0016] (a2) is a compound having multiple free isocyanate groups that react with the active hydrogen of (a1) to form urethane bonds. The isocyanate groups are preferably di- or tri-functional, and more preferably difunctional. In particular, when the isocyanate groups are difunctional, the cured coating has a higher elongation percentage and can ensure good moldability when formed into a film.

[0017] Examples of (a2) include aliphatic diisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate, and pentamethylene diisocyanate; aromatic diisocyanates such as tolylene diisocyanate (hereinafter referred to as TDI), diphenylmethane diisocyanate, and xylylene diisocyanate (hereinafter referred to as XDI); and aromatic diisocyanates such as isophorone diisocyanate (hereinafter referred to as IPDI), cyclohexane diisocyanate, and 4,4-dicyclohexylmethane diisocyanate (hereinafter referred to as H 12 Examples of suitable diisocyanates include alicyclic diisocyanates such as MDI (hereinafter referred to as "MDI") and isocyanurates, which are trimers of these diisocyanates. These may be used alone or in combination of two or more. Among these, aromatic diisocyanates are preferred because they have high cohesion properties and therefore excellent mechanical and thermal properties, with TDI and XDI being more preferred. Furthermore, alicyclic diisocyanates are preferred because they have a good balance between weather resistance and rigidity, with IPDI and H 12 MDI is more preferred.

[0018] The (a3) ​​is a (meth)acrylate having an active hydrogen that reacts with a polyisocyanate obtained by reacting (a1) and (a2). Examples include monofunctional hydroxy(meth)acrylates such as 2-hydroxyethyl(meth)acrylate, 3-hydroxypropyl(meth)acrylate, and 4-hydroxybutyl(meth)acrylate; bifunctional hydroxy(meth)acrylates such as glycerin di(meth)acrylate and pentaerythritol di(meth)acrylate; and trifunctional or higher (meth)acrylates such as pentaerythritol tri(meth)acrylate, diglycerin tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, and dipentaerythritol penta(meth)acrylate. Among these, bifunctional or lower hydroxy(meth)acrylates are preferred in terms of the balance between moldability and abrasion resistance, and monofunctional hydroxyalkyl(meth)acrylates are more preferred. In terms of the mechanical strength of the resulting cured film, the number of carbon atoms between the (meth)acryloyl group and the hydroxyl group is more preferably 2 to 4, and 2-hydroxyethyl acrylate (hereinafter referred to as 2HEA) is particularly preferred.

[0019] The synthesis method for (A) is not particularly limited, and known methods can be used. The reaction can be carried out without a solvent. However, as the molecular weight of (A) increases, stirring may become difficult. Therefore, ketones such as MEK or aromatic inert solvents such as xylene may be used. The use of a catalyst is preferred for the reaction between (a1) and (a2) and the reaction between a polyisocyanate and (a3). Examples of such catalysts include tin-based catalysts such as dioctyltin dilaurate and dibutyltin dilaurate, and metal alkoxide-based catalysts such as cobalt naphthenate. In the reaction between a polyisocyanate and (a3), the progress of the reaction can be confirmed by the decrease in the peak derived from the isocyanate group in the infrared absorption spectrum. The reaction temperature can be appropriately set, but is preferably 40 to 100°C, more preferably 60 to 90°C.

[0020] The blending ratio of (a1) and (a2) when reacting them can be determined by the ratio of the number of moles of hydroxyl groups in (a1) to the number of moles of isocyanate groups in (a2). (a1) is always smaller than (a2), and the closer the molar ratio of (a1) to (a2) is to 1, the higher the number-average molecular weight of (A) tends to be. The ratio (OH groups / NCO groups) of the total number of moles of hydroxyl groups in (a1) and (a3) ​​to the number of moles of isocyanate groups in (a2) is preferably 0.85 to 1.20, more preferably 0.95 to 1.15, and particularly preferably 1.0 to 1.10. By adjusting the ratio within this range, terminal isocyanate groups in the polyurethane are converted to (meth)acryloyl groups, thereby reducing the amount of remaining isocyanate groups.

[0021] The weight-average molecular weight (hereinafter referred to as Mw) of (A) is preferably 1,000 to 100,000, more preferably 3,000 to 30,000, and particularly preferably 6,000 to 20,000. A weight-average molecular weight of 1,000 or more ensures sufficient moldability, while a weight-average molecular weight of 100,000 or less ensures sufficient abrasion resistance and scratch resistance due to self-repairing properties. Mw was measured and calculated by gel permeation chromatography using a column with a styrene-divinylbenzene-based packing material and a tetrahydrofuran eluent, relative to standard polystyrene.

[0022] The blending amount of (A) is preferably 70 to 95% by weight, more preferably 80 to 94% by weight, and particularly preferably 85 to 93% by weight, based on the total solid content. By making it 70% by weight or more, sufficient self-repairing properties can be ensured, and by making it 95% by weight or less, sufficient scratch resistance and scratch resistance with fingernails can be ensured.

[0023] The leveling agent (B) used in this resin composition is a silicone-based compound that is formulated to improve leveling properties during application and the scratch resistance of the cured film. It contains a polyether-modified polysiloxane, which is particularly effective at leveling large differences in surface tension across the coating surface. Examples of polyether-modified polysiloxanes include compounds with polyether side chains, such as ethylene oxide or propylene oxide, attached to the side chains of a polydimethylsiloxane main chain. Even though they are both silicone-based, polyester-modified polysiloxanes tend to exhibit reduced scratch resistance. Furthermore, the presence of a reactive functional group, such as an acryloyl group, that can polymerize with the binder resin prevents bleeding and other bleed-out effects from the cured film over time, ensuring long-term scratch resistance.

[0024] The amount of (B) is preferably 0.1 to 3 wt % of the total solid content, and more preferably 0.3 to 2 wt %. By adjusting the amount to this range, sufficient scratch resistance and leveling properties can be ensured, resulting in a stable coating film appearance.

[0025] The photopolymerization initiator (C) used in this resin composition is used primarily for the purpose of improving the initiation efficiency of the polymerization reaction, which proceeds upon irradiation with active energy rays such as ultraviolet rays or electron beams. For example, general-purpose photopolymerization initiators such as intramolecular cleavage types (benzyl ketals, α-hydroxyacetophenones, α-aminoacetophenones, and acylphosphine oxides) and hydrogen abstraction types (benzophenones, thioxanthones) can be used. By arbitrarily selecting the light absorption wavelength of the polymerization initiator, it is possible to impart curability over a wide wavelength range, from the ultraviolet region to the visible light region.

[0026] Specifically, benzyl ketals include 2,2-dimethoxy-1,2-diphenylethan-1-one, α-hydroxyacetophenones include 1-hydroxycyclohexylphenyl ketone, α-aminoacetophenones include 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one, and acylphosphine oxides include 2,4,6-trimethylbenzoyl-diphenylphosphine oxide and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, and these can be used alone or in combination of two or more.

[0027] Among these, it is preferable to use an α-hydroxyacetophenone system, which has high reactivity and is resistant to yellowing. Among the α-hydroxyacetophenone systems, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one (hereinafter referred to as Omnirad 2959) and 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)benzyl]phenyl}-2-methylpropan-1-one (hereinafter referred to as Omnirad 127D) are preferable because of their excellent curability and good adhesion to substrates, and it is particularly preferable to use these in combination. In addition to these, benzil ketal systems, acylphosphine oxide systems, α-aminoacetophenone systems, other α-hydroxyacetophenone systems, etc. may also be used in combination.

[0028] The amount of (C) added per 100 parts by weight of the radically polymerizable component is preferably 3 to 15 parts by weight, more preferably 5 to 12 parts by weight. By adding 3 parts by weight or more, the composition can be sufficiently cured with an appropriate amount of active energy ray irradiation, while by adding 15 parts by weight or less, an excessive amount is not added, and a cured product having sufficient transparency can be obtained.

[0029] The resin composition preferably further contains a light stabilizer (D). Examples of (D) include radical scavengers (d1) that efficiently trap alkyl radicals and peroxy radicals generated from polymers photodegraded by ultraviolet light, and ultraviolet absorbers (d2) that convert absorbed ultraviolet energy into heat energy, thereby inhibiting polymer decomposition.

[0030] Examples of (d1) include hindered amines (hereinafter referred to as HALS), hindered phenols, and aromatic amines, which can be used alone or in combination of two or more. Among these, HALS is preferred because it has a high radical scavenging efficiency even at low concentrations. The amount of (d1) added is preferably 0.3 to 3.0 wt. % of the total solid content, and more preferably 0.5 to 2.0 wt. By adjusting the amount to this range, sufficient light stability can be ensured. Commercially available HALS products include Tinuvin 123 and Tinuvin 249 (trade names: manufactured by BASF Japan Ltd.).

[0031] (d2) is a radical chain initiation inhibitor with an absorption band in the high-energy, harmful ultraviolet region. Its use in combination with (d1) can further improve and stabilize weather resistance. Examples include benzotriazoles, triazines, and benzophenones, which can be used alone or in combination. Among these, hydroxyphenyltriazines, which are capable of strongly absorbing the long-wavelength portion of ultraviolet light, are preferred. The blending amount of (d2) is preferably 0.1 to 3.0 wt.% based on the total solid content, and more preferably 0.2 to 1.0 wt.%. This range ensures sufficient ultraviolet absorption characteristics. The blending amount of (D), the sum of (d1) and (d2), is preferably 0.5 to 5.0 wt.% based on the total solid content, and more preferably 0.8 to 3.0 wt.%. At 0.5 wt.% or more, improved weather resistance can be expected, while at 5.0 wt.% or less, sufficient adhesion to the substrate can be ensured without excessive blending. Commercially available products of (d2) include Tinuvin 460 and 477 (trade names: manufactured by BASF Japan Ltd.).

[0032] To the present resin composition, reactive diluents, adhesion promoters, bluing agents, pigments, antifoaming agents, thickeners, anti-suspending agents, antistatic agents, anti-fogging agents, antibacterial agents, waxes, matting agents, hydrophilic agents, water-repellent agents, inorganic fillers, organic fine particles, and the like may be added as needed within the range that does not impair the performance.

[0033] As the reactive diluent, it is preferable to use a polyfunctional (meth)acrylate because it has low viscosity and excellent compatibility with (A). For example, bifunctional diluents include (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, and dicyclopentanyl diacrylate; trifunctional dimethylolpropane tri(meth)acrylate and pentaerythritol tri(meth)acrylate; tetrafunctional ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, and diglycerin tetra(meth)acrylate; pentafunctional dipentaerythritol penta(meth)acrylate; and hexafunctional dipentaerythritol hexa(meth)acrylate. These diluents can be used alone or in combination of two or more.

[0034] The amount of the reactive diluent is preferably 10 parts by weight or less, more preferably 5 parts by weight or less, per 100 parts by weight of (A). By using 10 parts by weight or less, sufficient self-repairing properties can be ensured. The blending ratio relative to the total solid content is preferably 8% by weight or less, more preferably 3% by weight or less.

[0035] When applying the resin composition to a plastic substrate, it may be diluted with a solvent to improve coating properties. Examples of such solvents include alcohol-based solvents such as ethanol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, and diacetone alcohol; ketone-based solvents such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, and cyclohexanone; ester-based solvents such as ethyl acetate and butyl acetate; ether-based solvents such as propylene glycol monomethyl ether (PGM), diethyl ether, and diisopropyl ether; and hydrocarbon-based solvents such as cyclohexane and methylcyclohexane. These solvents may be used alone or in combination. The solids content of the diluted solution is typically 10 to 70%, but there are no specific limitations and the viscosity can be adjusted appropriately to achieve a coating viscosity that is easy to apply.

[0036] Examples of plastic substrates onto which the present resin composition can be applied include polyester films, triacetyl cellulose films, polycarbonate films, polysulfone films, nylon films, cycloolefin films, acrylic (hereinafter referred to as PMMA) films, polyimide films, ABS films, polyolefin films, PVC films, and PVA films.

[0037] Among these, it is preferable to use a composite substrate made of a polycarbonate (hereinafter referred to as PC) substrate, which has excellent impact resistance and high heat resistance, and an acrylic substrate, which has high transparency and hardness. Here, the composite substrate made of a PC substrate and an acrylic substrate (hereinafter referred to as the present composite substrate) means a resin laminate having an acrylic resin layer on at least one side of a PC resin layer. The method for laminating the PC resin and the acrylic resin is preferably co-extrusion molding.

[0038] In order to improve adhesion to the resin composition, the plastic substrate may be subjected to a surface treatment such as a primer treatment, a sandblasting method, a solvent treatment, or the like to create a rough surface, or a surface oxidation treatment such as a corona discharge treatment, a chromic acid treatment, or an ozone / ultraviolet irradiation treatment.

[0039] The method for applying the present resin composition is not particularly limited, and it can be formed by known coating methods such as spray coating, roll coating, die coating, air knife coating, blade coating, spin coating, reverse coating, gravure coating, wire bar coating, etc., or printing methods such as gravure printing, screen printing, offset printing, inkjet printing, etc. The thickness of the coated film when dry can be, for example, 1 μm to 10 μm, but is not limited to this.

[0040] The light source for UV irradiation used to cure the resin composition includes low-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, carbon arc lamps, xenon lamps, metal halide lamps, LED lamps, and electrodeless UV lamps. The irradiation atmosphere may be air or an inert gas such as nitrogen or argon. Furthermore, the curing property can be further improved by heating the coating film during UV irradiation using a back roll or an IR heater. The irradiation conditions are an irradiation intensity of 500 mW / cm. 2 ~3000mW / cm 2 , exposure dose 50-400mJ / cm 2 are exemplified, but are not limited to these.

[0041] A film (hereinafter referred to as the present film) obtained by coating the present resin composition on a plastic substrate and curing it preferably has a breaking elongation of 100% or more, more preferably 150% or more, in an atmosphere at 130° C. By ensuring that the breaking elongation is 100% or more, sufficient moldability can be expected.

[0042] The film can be provided with a decorative layer as needed. Examples of decorative methods include printing and metal deposition, and both methods may be used. Furthermore, an adhesive layer or a primer layer may be provided to improve adhesion to the injection molding resin.

[0043] A protective film may be attached to the film to protect the surface to which the composition is applied. Using a protective film can prevent scratches during insert molding or out-molding processes, which is expected to improve yield.

[0044] The method of using the present film in insert molding involves, for example, placing the surface coated with the present composition facing the inner wall of the mold (so that the surface opposite the cured layer of the present composition is in contact with the molding resin), and preforming the film to conform to the shape of the mold as needed.Then, the mold is closed and the molten molding resin is injected into the cavity, and the resin is allowed to solidify, thereby forming a resin molded product.

[0045] The preforming method may be a method in which the film is preheated to above its softening point and placed in a mold, followed by vacuum suction through suction holes in the mold, or a known molding method such as vacuum forming, compressed air forming, press molding, etc., using a molding mold separate from the injection molding mold. It is also possible to perform molding and integral molding of the injected resin simultaneously by the injection pressure of the molding resin without performing these preforming methods.

[0046] The resin to be injection-molded can be any known resin that can be injection-molded. Examples include polyethylene resin, polypropylene resin, polystyrene resin, ABS resin, AS resin, acrylic resin, urethane resin, polyester resin, polycarbonate resin, polyphenylene ether resin, polyacetal resin, and polysulfone resin. These resins can be used alone or in combination of two or more. In the case of large sizes such as automobile bodies, or small sizes but thin thicknesses, problems such as warping can be avoided by making the shrinkage rate after molding similar to that of HC film.

[0047] Furthermore, by coloring the injection molding resin itself, it is possible to eliminate the decorative layer of the film or to blend the color of the decorative layer with that of the injection molding resin, resulting in a more sophisticated appearance. Furthermore, when replacing products whose exteriors are usually colored with paint, such as automobile bodies, with insert molding, coloring the injection-molded resin makes it possible to omit the exterior painting with paint. In this case, it is possible to eliminate appearance defects such as orange peel and pitting that often occur with exterior painting.

[0048] Furthermore, this film can also be used for out-molding. For example, it can be used in TOM (Three-Dimensional Overlay Method) molding. TOM molding is a film molding method in which a pre-formed substrate is molded in an airtight box and three-dimensional surface decoration is applied using vacuum and pressure molding. By using this HC film, it can be used for large three-dimensional products regardless of the substrate material.

[0049] The present invention will be described in detail below with reference to examples and comparative examples, but these are intended to be specific examples and are not intended to limit the scope of the present invention. Unless otherwise specified, measurements were carried out at a room temperature of 25°C and a relative humidity of 65%. The blend amounts are expressed in parts by weight as solid content. [Example]

[0050] A polyfunctional urethane (meth)acrylate (hereinafter referred to as ureac) having a skeleton was prepared by reacting the following components. Urea 1:2HEA-TDI-PCD-TDI-2HEA skeleton, bifunctional, Mw 9,500 Urea 2: 2HEA-XDI-PCD-XDI-2HEA skeleton, same, Mw 17,000 Urea 3:2HEA-H 12 MDI-PCD-H 12 MDI-2HEA skeleton, same, Mw15,000 Urea 4: 2HEA-IPDI-PCD-IPDI-2HEA skeleton, same, Mw 10,000 Ureac A: PETA-(IPDI-EG-)n-IPDI-PETA skeleton, hexafunctional, Mw6,200 *PCD: Polycarbonate diol, PETA: Pentaerythritol triacrylate, EG: Ethylene glycol

[0051] Examples 1 to 11 The above-mentioned Urea 1 was used as (A), a polyether-modified polysiloxane leveling agent as (B), and Omnirad 2959 and 127D (trade names: manufactured by IGM Resins) as (C) in the formulation shown in Table 1, and these were stirred until uniformly dissolved and dispersed. Ethyl acetate was then added to the mixture so that the solid content was 30%, and the mixture was stirred to obtain the photocurable resin composition of Example 1.

[0052] Examples 2 to 7 In addition to the materials used in Example 1, the above-mentioned Ureacs 2 to 4 were used as (A), a reactive polyether-modified polysiloxane leveling agent as (B), Tinuvin 249 (trade name: manufactured by BASF Japan Ltd.) as (e1), and Tinuvin 477 (trade name: manufactured by BASF Japan Ltd.) as (e2) in the formulations shown in Table 1. These were stirred until uniformly dissolved and dispersed, and ethyl acetate was added to the mixture so that the solid content was 30%, followed by dilution and stirring to obtain the photocurable resin compositions of Examples 2 to 7.

[0053] Comparative Examples 1 to 4 In addition to the materials used in the examples, the above-mentioned ureac A was used as the oligomer, and reactive polyester-modified polysiloxane, acrylic, and fluorine-based leveling agents were used as leveling agents in place of (B). These were mixed in the formulations shown in Table 2 and stirred until uniformly dissolved and dispersed, and then ethyl acetate was added to the mixture so that the solid content was 30%, followed by dilution and stirring to obtain photocurable resin compositions for Comparative Examples 1 to 4.

[0054] Table 1 JPEG2026018122000002.jpg122160

[0055] Table 2 JPEG2026018122000003.jpg148132

[0056] The evaluation method was as follows.

[0057] Preparation of evaluation films The photocurable resin compositions prepared in the examples and comparative examples were applied to Iupilon film (product name: DF02PUL, manufactured by Mitsubishi Gas Chemical Company, Inc., thickness 125 μm, PMMA / PC laminated film) so that the dry film thickness was 3 μm on the PMMA side, and after drying in a thermostatic oven at 80°C for 1 minute, the film was exposed to a high-pressure mercury lamp with an output of 1300 mW / cm. 2 The film was irradiated with ultraviolet light so that the cumulative light amount was 200 mJ, and a film for evaluation was prepared.

[0058] Haze: Measured in accordance with JIS K7136 using a haze meter HAZE-GARDi manufactured by Byk-Gardner Co., Ltd. Evaluation method: less than 1.0% was rated as ○, and 1.0% or more was rated as ×.

[0059] Formability: The HC film was cut into a size of 25 mm wide x 110 mm long, and a tensile test was carried out using a TechnoGraph TGI-1KN manufactured by Minebea Co., Ltd., with a chuck distance of 50 mm, an ambient temperature of 130°C, and a pulling speed of 300 mm / min. Cracks were visually checked for evaluation, and an elongation rate of 100% or more was rated as ◯, and an elongation rate of less than 100% was rated as ×. Calculation formula: Calculate how many mm it has stretched based on 50 mm. Stretched length (mm) / 50mm x 100 = stretch rate %

[0060] Adhesion: In accordance with the cross-cut method of JIS K 5600-5-6, a 10 x 10 grid was created on the coated surface at 1 mm intervals, and cellophane tape CT-24 (trade name: manufactured by Nichiban Co., Ltd.) was applied and pulled upward to check for peeling, with a ◯ indicating no peeling and an × indicating peeling. No peeling: 100 / 100, Peeling: 0 / 100~99 / 100

[0061] Scratch resistance: Using a Toyo Seiki abrasion tester, the contact area is 4cm2 A 500g load was placed on the steel wool #0000 and the surface was reciprocated 10 times at a reciprocating speed of 30 times / minute. After leaving it at room temperature for 1 minute, the coating surface was visually inspected. The evaluation was rated as ◯ when the scratches were almost completely repaired, △ when slight scratches remained, and × when clear scratches remained.

[0062] Resistance to fingernail scratches: When the surface of the coating was scratched with a fingernail, if it was slippery and not easily scratched, it was rated as ◯, and if it was not slippery and left a scratch, it was rated as ×.

[0063] Example evaluation results Table 3 JPEG2026018122000004.jpg54135

[0064] Comparative Example Evaluation Results Table 4 JPEG2026018122000005.jpg82135

[0065] The examples were satisfactory in all respects, ie, haze, moldability, adhesion, scratch resistance, and scratch resistance.

[0066] On the other hand, Comparative Examples 1 to 3, which used leveling agents other than polyether-modified polysiloxane-based leveling agents, had poor fingernail scratch resistance, and Comparative Example 4, which used a urea other than (A), had poor scratch resistance, and neither was suitable for the present invention.

Claims

1. A film having a cured layer of a photocurable resin composition on a plastic substrate, The photocurable resin composition comprises a polyfunctional urethane (meth)acrylate (A) having a polycarbonate skeleton, a silicone-based leveling agent (B), and a photopolymerization initiator (C), and (B) comprises a polyether-modified polysiloxane.

2. 2. The film according to claim 1, wherein the polyfunctional urethane (meth)acrylate (A) is a polyfunctional urethane (meth)acrylate obtained by reacting a polycarbonate polyol (a1) with a polyisocyanate (a2) to produce a polyisocyanate, and then further reacting the polyisocyanate with a hydroxyl group-containing (meth)acrylate (a3).

3. 2. The film according to claim 1, wherein the photopolymerization initiator (C) comprises an α-hydroxyacetophenone-based initiator.

4. 2. The film according to claim 1, wherein the plastic substrate is a composite substrate of polycarbonate and acrylic.

5. 5. The film according to claim 1, which is used for film molding.

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