UV-curable silicone composition and cured product thereof

Abstract

A silicone composition containing (A) a polysiloxane that has (a) a unit of formula (1) (R1 represents a monovalent hydrocarbon group, R2 represents an oxygen atom, etc., R3 represents an acryloyloxyalkyl group, etc., p represents 0 ≤ p ≤ 10, and a represents 1 ≤ a ≤ 3.) and (b) a unit of R1Rf1SiO2 / 2 (R1 is the same as above. Rf 1 represents a C1-8 fluorinated alkyl group.) and in which 5% or more of the monovalent organic groups on Si are the fluorinated alkyl groups, (B) a polysiloxane resin that has (c) a unit of formula (2) or formula (2') (R6 represents a monovalent hydrocarbon group, R7 represents an oxygen atom, etc., R8 represents an acryloyloxyalkyl group, etc., q represents 0 ≤ q ≤ 10, and c represents 1 ≤ c ≤ 3.) and (d) a unit of Rf2SiO3 / 2 (Rf2 represents a C1-8 fluorinated alkyl group.) and in which 5% or more of the monovalent organic groups on Si are CF3 groups, and (C) a photopolymerization initiator, is cured rapidly by UV irradiation and yields a releasable cured product.

Description

UV-curable silicone composition and cured product thereof

[0001] The present invention relates to an ultraviolet-curable silicone composition and a cured product thereof.

[0002] Materials with fine patterns formed on their surfaces, such as lens materials for 3D sensors, are typically imprint molded using a mold. Imprint molding can be performed in two ways: by molding the target material directly from the mold, or by creating a replica mold from the mold and then replicating the lens material from that replica mold. The latter method is significantly more advantageous in terms of production efficiency. To improve yield, a release treatment is typically applied to the surfaces of the mold and replica mold material to prevent adhesion between the lens material and the replica mold. However, there is a need to simplify the release agent application process.

[0003] One such material known is a fluorine-containing acrylic resin (Patent Document 1). However, the technology using this material requires cleaning with a solvent and heating after molding the replica mold material, and there is a need to simplify the process.

[0004] Patent No. 6881567

[0005] The present invention has been made in view of the above circumstances, and has as its object to provide an ultraviolet-curable silicone composition that gives a cured product with mold releasability, and the cured product thereof.

[0006] As a result of extensive research conducted by the present inventors in order to achieve the above-mentioned object, they discovered that by using a specific organopolysiloxane having a (meth)acryloyloxy-containing group and a fluorinated alkyl group bonded to a silicon atom, and an organopolysiloxane resin having a (meth)acryloyloxy-containing group and a fluorinated alkyl group bonded to a silicon atom, it is possible to obtain an ultraviolet-curable silicone composition that cures rapidly upon exposure to ultraviolet light and gives a cured product that has mold releasability, and they have completed the present invention.

[0007] That is, the present invention provides: 1. (A) (a) a compound represented by the following general formula (1): (In the formula, R 1each independently represents a monovalent hydrocarbon group having 1 to 20 carbon atoms; R 2 represents an oxygen atom or an alkylene group having 1 to 20 carbon atoms, R 3 are each independently an acryloyloxyalkyl group, a methacryloyloxyalkyl group, an acryloyloxyalkyloxy group, or a methacryloyloxyalkyloxy group, p is a number satisfying 0≦p≦10, and a is a number satisfying 1≦a≦3. 1 Rf 1 SiO 2 / 2 (R 1 has the same meaning as above, and Rf 1 represents a fluorine-substituted alkyl group having 1 to 8 carbon atoms bonded to a silicon atom, and 5% or more of the total number of monovalent organic groups bonded to silicon atoms are fluorine-substituted alkyl groups having 1 to 8 carbon atoms: 100 parts by mass (B) (c) an organopolysiloxane having a unit represented by the following general formula (2) or the following general formula (2'): (In the formula, R 6 each independently represents a monovalent hydrocarbon group having 1 to 20 carbon atoms; R 7 represents an oxygen atom or an alkylene group having 1 to 20 carbon atoms, R 8 are each independently an acryloyloxyalkyl group, a methacryloyloxyalkyl group, an acryloyloxyalkyloxy group, or a methacryloyloxyalkyloxy group, q is a number satisfying 0≦q≦10, and c is a number satisfying 1≦c≦3. 2 SiO 3 / 2 (Rf 2represents a fluorine-substituted alkyl group having 1 to 8 carbon atoms bonded to a silicon atom.), and wherein 5% or more of the total number of monovalent organic groups bonded to silicon atoms are trifluoropropyl groups, and (C) 0.01 to 20 parts by mass of a photopolymerization initiator; 2. The ultraviolet-curable silicone composition of 1 containing 1 to 1000 parts by mass of (D) a monofunctional (meth)acrylate compound not containing a siloxane structure per 100 parts by mass of component (A); 3. A cured product of the ultraviolet-curable silicone composition of 1 or 2; 4. The cured product of 3 having a Type D hardness of 30 or more as specified in JIS K6253-3:2012.

[0008] The ultraviolet-curable silicone composition of the present invention cures well when irradiated with ultraviolet light, and the cured product has excellent mold releasability, making it suitable as a replica molding material.

[0009] The present invention will be described in detail below. The ultraviolet-curable silicone composition according to the present invention comprises: (A) (a) a unit represented by the following general formula (1), and (b) R 1 Rf 1 SiO 2 / 2 (R 1 represents a monovalent hydrocarbon group having 1 to 20 carbon atoms, and Rf 1 represents a fluorine-substituted alkyl group having 1 to 8 carbon atoms bonded to a silicon atom.) 100 parts by mass of an organopolysiloxane having a unit represented by the following general formula (2): 2 SiO 3 / 2 (Rf 2 represents a fluorine-substituted alkyl group having 1 to 8 carbon atoms bonded to a silicon atom, and in which 5% or more of the total number of monovalent organic groups bonded to silicon atoms are trifluoropropyl groups; and (C) 0.01 to 20 parts by mass of a photopolymerization initiator.

[0010] (A) Organopolysiloxane The component (A) used in the present invention is a crosslinking component of the composition, and comprises the following (a) siloxane units represented by the following general formula (1) and (b) R 1 Rf 1 SiO 2 / 2 and the main chain is essentially composed of repeating diorganosiloxane units.

[0011]

[0012] In formula (1), R 1 each independently represents a monovalent hydrocarbon group having 1 to 20 carbon atoms, preferably a monovalent hydrocarbon group having 1 to 10 carbon atoms, more preferably a monovalent hydrocarbon group having 1 to 8 carbon atoms, excluding aliphatic unsaturated groups; R 2 represents an oxygen atom or an alkylene group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, and more preferably 1 to 5 carbon atoms; R 3 each independently represents an acryloyloxyalkyl group, a methacryloyloxyalkyl group, an acryloyloxyalkyloxy group, or a methacryloyloxyalkyloxy group.

[0013] In formula (1), R 1 The monovalent hydrocarbon group having 1 to 20 carbon atoms may be linear, branched, or cyclic, and specific examples thereof include alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-hexyl, cyclohexyl, n-octyl, 2-ethylhexyl, and n-decyl; alkenyl groups such as vinyl, allyl (2-propenyl), 1-propenyl, isopropenyl, and butenyl; aryl groups such as phenyl, tolyl, xylyl, and naphthyl; and aralkyl groups such as benzyl, phenylethyl, and phenylpropyl. Some or all of the hydrogen atoms bonded to the carbon atoms of these monovalent hydrocarbon groups may be substituted with other substituents, and specific examples thereof include halogen-substituted hydrocarbon groups such as chloromethyl, bromoethyl, trifluoropropyl, and cyanoethyl, and cyano-substituted hydrocarbon groups. Among these, R 1As the alkyl group, an alkyl group having 1 to 5 carbon atoms and a phenyl group are preferred, and a methyl group, an ethyl group and a phenyl group are more preferred.

[0014] Also, R 2 The alkylene group having 1 to 20 carbon atoms may be linear, branched, or cyclic, and specific examples thereof include methylene, ethylene, propylene, trimethylene, tetramethylene, isobutylene, pentamethylene, hexamethylene, heptamethylene, octamethylene, nonamethylene, and decylene groups. 2 is preferably an oxygen atom, methylene, ethylene or trimethylene group, more preferably an oxygen atom or an ethylene group.

[0015] Furthermore, R 3 The number of carbon atoms in the alkyl (alkylene) group in the acryloyloxyalkyl group, methacryloyloxyalkyl group, acryloyloxyalkyloxy group, or methacryloyloxyalkyloxy group is not particularly limited, but is preferably 1 to 10, and more preferably 1 to 5. Specific examples of these alkyl groups include R 1 Among the groups exemplified in R, those having 1 to 10 carbon atoms can be mentioned. 3 Specific examples of the compound include, but are not limited to, those represented by the following formulas:

[0016]

[0017] In the above formula, b is a number that satisfies 1≦b≦4, and preferably a number that satisfies 1≦b≦3. 5 is an alkylene group having 1 to 10 carbon atoms, preferably an alkylene group having 1 to 5 carbon atoms, and among these, methylene, ethylene and trimethylene groups are preferred, with an ethylene group being more preferred.

[0018] In formula (1), p is a number that satisfies 0≦p≦10, preferably 0≦p≦5, and more preferably 0 or 1. a is a number that satisfies 1≦a≦3, and preferably 1 or 2.

[0019] The location of the siloxane unit represented by (a) above in the organopolysiloxane molecule of component (A) may be at one or both ends of the molecular chain, and the unit represented by (a) above may also be present in a side chain of the molecular chain. However, from the perspective of the mechanical properties of the resulting cured product, it is preferable that the unit represented by (a) above be present only at both ends.

[0020] (b) R 1 Rf 1 SiO 2 / 2 In the siloxane unit represented by the formula: 1 has the same meaning as above, and among them, an alkyl group having 1 to 5 carbon atoms and a phenyl group are preferred, and a methyl group, an ethyl group and a phenyl group are more preferred.

[0021] Rf 1 represents a fluorine-substituted alkyl group having 1 to 8 carbon atoms bonded to a silicon atom. Examples of the fluorine-substituted alkyl group include trifluoromethyl, 3,3,3-trifluoropropyl, 3,3,4,4,4-pentafluorobutyl, 3,3,4,4,5,5,5-heptafluoropentyl, 3,3,4,4,5,5,6,6,6-nonafluorohexyl, 3,3,4,4,5,5,6,6,7,7,7-undecafluoroheptyl, and 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl groups, with 3,3,3-trifluoropropyl being preferred.

[0022] In the component (A), siloxane units other than the above (a) and (b), such as R 1 2SiO 2 / 2 Units and R 1 3SiO 1 / 2 Units (wherein R 1 has the same meaning as above.) etc.

[0023] Of the total number of monovalent organic groups bonded to silicon atoms in component (A), at least 5%, preferably 5 to 50%, and more preferably 10 to 50% are fluorine-substituted alkyl groups having 1 to 8 carbon atoms. If the proportion of fluorine-substituted alkyl groups having 1 to 8 carbon atoms is less than 5%, the resulting cured product may have insufficient releasability.

[0024] The viscosity of the organopolysiloxane of component (A) at 25°C is preferably 10 to 200,000 mPa s, and more preferably 10 to 100,000 mPa s, in order to further improve the workability of the composition and the mechanical properties of the cured product. In the present invention, the viscosity can be measured using a rotational viscometer (for example, a BL type, BH type, BS type, cone-plate type, or rheometer) (the same applies hereinafter).

[0025] Specific examples of the organopolysiloxane of component (A) include those represented by the following formula, but are not limited to these.

[0026] (In the formula, R 1 and Rf 1 has the same meaning as above, and n is a number that makes the viscosity of the organopolysiloxane the above value, preferably 1 to 800, and more preferably 10 to 500.

[0027] Such organopolysiloxanes can be produced by known methods. For example, the polysiloxane represented by formula (3) above can be obtained by reacting 2-hydroxyethyl acrylate with the hydrosilylation reaction product of a dimethylsiloxane-trifluoropropylmethylsiloxane copolymer endblocked at both ends with dimethylvinylsiloxy groups and chlorodimethylsilane. The organopolysiloxanes represented by formulas (4) and (5) above can be obtained as the hydrosilylation reaction product of a dimethylsiloxane-trifluoropropylmethylsiloxane copolymer endblocked at both ends with dimethylvinylsiloxy groups and 3-(1,1,3,3-tetramethyldisiloxanyl)propyl methacrylate (CAS No. 96474-12-3). The organopolysiloxane represented by the above formula (6) can be obtained by reacting 2-hydroxyethyl acrylate with the hydrosilylation reaction product of a dimethylsiloxane-diphenylsiloxane copolymer endblocked at both ends with dimethylvinylsiloxy groups and dichloromethylsilane.

[0028] (B) Organopolysiloxane Resin Component (B) is one of the crosslinking components of the composition, and contains (c) a unit represented by the following general formula (2) or the following general formula (2'), and (d) Rf 2SiO 3 / 2 It is an organopolysiloxane resin having units.

[0029]

[0030] R 6 each independently represents a monovalent hydrocarbon group having 1 to 20 carbon atoms, preferably a monovalent hydrocarbon group having 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, excluding aliphatic unsaturated groups; R 7 represents an oxygen atom or an alkylene group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, and more preferably 1 to 5 carbon atoms; R 8 each independently represents an acryloyloxyalkyl group, a methacryloyloxyalkyl group, an acryloyloxyalkyloxy group, or a methacryloyloxyalkyloxy group.

[0031] R 6 The monovalent hydrocarbon group having 1 to 20 carbon atoms is the same as the R 1 Examples of the alkyl group include those exemplified in the above, and an alkyl group having 1 to 5 carbon atoms and a phenyl group are preferred, with a methyl group, an ethyl group and a phenyl group being more preferred.

[0032] R 7 The alkylene group having 1 to 20 carbon atoms includes the above R 2 and R 7 is preferably an oxygen atom, methylene, ethylene or trimethylene group, more preferably an oxygen atom or an ethylene group.

[0033] R 8 The number of carbon atoms in the alkyl (alkylene) group in the acryloyloxyalkyl group, methacryloyloxyalkyl group, acryloyloxyalkyloxy group, or methacryloyloxyalkyloxy group is not particularly limited, but is preferably 1 to 10, and more preferably 1 to 5. Specific examples of these alkyl groups include R 1 Among the groups exemplified in R, those having 1 to 10 carbon atoms can be mentioned. 3 Specific examples of R 3 Examples of the hydroxybenzoates include, but are not limited to, those exemplified above.

[0034] In formula (2), q is a number that satisfies 0≦q≦10, preferably 0≦q≦5, and more preferably 0 or 1. c is a number that satisfies 1≦c≦3, and is preferably 1 or 2.

[0035] (d) Rf 2 SiO 3 / 2 In units, Rf 2 represents a fluorine-substituted alkyl group having 1 to 8 carbon atoms bonded to a silicon atom, and the Rf 1 Examples include the same groups as those exemplified in the above, and a 3,3,3-trifluoropropyl group is preferred.

[0036] In component (B), siloxane units other than (c) and (d) above, such as R 1 3SiO 1 / 2 Unit, R 1 2SiO 2 / 2 Unit, R 1 Rf 2 SiO 2 / 2 Units and R 1 SiO 3 / 2 Units (wherein R 1 and Rf 2 has the same meaning as above.) etc.

[0037] The content of (c) units is preferably 5 to 30 mol %, more preferably 10 to 25 mol %, of all siloxane units in the organopolysiloxane resin of component (B).Within this range, the mechanical properties of the cured product are excellent.

[0038] Of the total number of monovalent organic groups bonded to silicon atoms in component (B), at least 5%, preferably 5 to 90%, and more preferably 30 to 90% are fluorine-substituted alkyl groups having 1 to 8 carbon atoms. If the proportion of fluorine-substituted alkyl groups having 1 to 8 carbon atoms is less than 5%, the resulting cured product may have insufficient releasability.

[0039] The number average molecular weight of component (B) is preferably 500 to 30,000, more preferably 1,000 to 20,000. Within this range, the workability of the composition is improved. The number average molecular weight is a value measured by gel permeation chromatography (GPC) in terms of standard polystyrene.

[0040] The blending amount of component (B) is 1 to 1,000 parts by mass, and more preferably 200 to 800 parts by mass, per 100 parts by mass of component (A). Within this range, the workability of the composition and the mechanical properties of the cured product are excellent. Component (B) may be used alone or in combination of two or more types.

[0041] The organopolysiloxane resin of component (B) can be produced by known methods, for example, by co-hydrolysis condensation of a hydrolyzable silane mixture containing a fluorine-substituted alkyltrialkoxysilane and a (meth)acrylic group-containing dimethoxysilane. Examples of the fluorine-substituted alkyltrialkoxysilane include 3,3,3-trifluoropropyltrimethoxysilane, and examples of the (meth)acrylic group-containing dimethoxysilane include 3-(methacryloyloxy)propylmethyldimethoxysilane and the hydrosilylation reaction product of dimethoxymethylvinylsilane and 3-(1,1,3,3-tetramethyldisiloxanyl)propyl methacrylate.

[0042] (C) Photopolymerization initiator Specific examples of photopolymerization initiators that can be used in the present invention include 2,2-diethoxyacetophenone, 2,2-dimethoxy-1,2-diphenylethan-1-one (Omnirad 651), 1-hydroxy-cyclohexyl-phenyl-ketone (Omnirad 184), 2-hydroxy-2-methyl-1-phenyl-propan-1-one (Omnirad 1173), 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]-phenyl}-2-methyl-propan-1-one (Omnirad 127), phenylglyoxylic acid methyl ester (Omnirad MBF), 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one (Omnirad 907), 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butan-1-one (Omnirad 369), 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)butan-1-one (Omnirad 379EG), bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide (Omnirad 819), 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (Omnirad TPO) and the like (all manufactured by IGM Resins B.V.), and these may be used alone or in combination of two or more.

[0043] As the component (C), from the viewpoint of being less susceptible to oxygen inhibition during UV curing and improving surface curing properties, an α-aminoacetophenone type photopolymerization initiator is preferred, and examples thereof include 2,2-diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one (Omnirad 1173), bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide (Omnirad 819), 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (Omnirad TPO), 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butan-1-one (Omnirad 369), and 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)butan-1-one (Omnirad 379EG) (all of which are IGM products). Resins B.V.) is more preferred.

[0044] The amount of the photopolymerization initiator added is preferably 0.01 to 50 parts by mass, more preferably 0.1 to 10 parts by mass, per 100 parts by mass of (A) from the viewpoint of curability.

[0045] The composition of the present invention may further contain (D) a monofunctional (meth)acrylate compound not containing a siloxane structure for the purpose of adjusting the mechanical properties and viscosity. Specific examples include isoamyl acrylate, lauryl acrylate, stearyl acrylate, ethoxy-diethylene glycol acrylate, methoxy-triethylene glycol acrylate, 2-ethylhexyl-diglycol acrylate, phenoxyethyl acrylate, phenoxydiethylene glycol acrylate, tetrahydrofurfuryl acrylate, isobornyl acrylate, and dimethylol-tricyclodecane diacrylate. These compounds may be used alone or in combination. Of these, isobornyl acrylate and dimethylol-tricyclodecane diacrylate are particularly preferred.

[0046] When component (D) is used, the amount added is preferably in the range of 1 to 1,000 parts by mass per 100 parts by mass of component (A).

[0047] The composition of the present invention may further contain additives such as finely powdered silica, coloring materials (pigments or dyes), silane coupling agents, adhesion aids, polymerization inhibitors, antioxidants, ultraviolet absorbers, light stabilizers, etc., within the range that does not impair the effects of the present invention. Furthermore, the composition of the present invention may also be used by appropriately mixing it with other resin compositions.

[0048] Furthermore, when improvements in the handleability and ease of application to substrates of the ultraviolet-curable silicone pressure-sensitive adhesive composition of the present invention are required, it is acceptable to dilute the composition with an organic solvent before use, provided that the properties of the present invention are not impaired.

[0049] The ultraviolet-curable silicone composition of the present invention can be obtained by mixing the above components (A) to (C), and optionally component (D) and other components, in any order, followed by stirring, etc. There are no particular restrictions on the equipment used for stirring and other operations, and examples include a crusher, a three-roll mill, a ball mill, a planetary mixer, etc. These devices may also be used in combination as appropriate.

[0050] From the viewpoint of moldability and workability during application, the viscosity of the ultraviolet-curable silicone pressure-sensitive adhesive composition of the present invention, when measured using a rotational viscometer at 23° C., is preferably 5,000 Pa s or less, more preferably 3,000 Pa s or less, and even more preferably 1,500 Pa s or less. If the viscosity exceeds 5,000 Pa s, workability may be significantly impaired.

[0051] The ultraviolet-curable silicone composition of the present invention cures rapidly when irradiated with ultraviolet light. In this case, examples of the light source for the ultraviolet light to be irradiated include UVLED lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, carbon arc lamps, and xenon lamps. The irradiation dose (integral light amount) of the ultraviolet light is preferably 1 to 20,000 mJ / cm for a sheet formed from the composition of the present invention to a thickness of about 2.0 mm. 2 and more preferably 10 to 16,000 mJ / cm 2 That is, the illuminance is 100 mW / cm 2 When ultraviolet light is used, the ultraviolet light may be irradiated for about 0.01 to 160 seconds.

[0052] The cured product of the adhesive UV-curable silicone composition of the present invention preferably has a Type D hardness specified in JIS K6253-3:2012 of 30 or more, and more preferably 40 or more.

[0053] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples. The compounds of the respective components used in the examples are as follows: Me represents a methyl group, Rf represents a 3,3,3-trifluoropropyl group, and Vi represents a vinyl group.

[0054] Component (A)

[0055] Component (B) (B-1) Units represented by the following formula (7) / RfSiO 3 / 2 (B-2) A 50% by mass 1,3-bis(trifluoromethyl)benzene solution of an organopolysiloxane resin (number average molecular weight 1,200) having a molar ratio of units of 3 / 7: units represented by the following formula (8) / RfSiO 3 / 2 (B-3) A 50% by mass 1,3-bis(trifluoromethyl)benzene solution of an organopolysiloxane resin (number average molecular weight 1,115) having a molar ratio of units of 3 / 7: units represented by the following formula (8) / RfSiO 3 / 2 A 50% by weight 1,3-bis(trifluoromethyl)benzene solution of organopolysiloxane resin (number average molecular weight 1,055) with a unit molar ratio of 1 / 9

[0056] Component (C) (C-1) 2-hydroxy-2-methyl-1-phenyl-propan-1-one (Omnirad 1173, manufactured by IGM Resins B.V.) Component (D) (D-1) isobornyl acrylate (Light Acrylate IB-XA, manufactured by Kyoeisha Chemical Co., Ltd.)

[0057] (E) Component

[0058] Examples 1 to 8 and Comparative Example 1 The above components (A), (B), and (E) were mixed in the formulations shown in Table 1, and 1,3-bis(trifluoromethyl)benzene was distilled off at 100°C under reduced pressure. Components (C) and (D) were then mixed to prepare each of the silicone compositions shown in Table 1. The resulting compositions and cured products were evaluated for the following properties. The results are also shown in Table 1.

[0059] [Viscosity] The viscosity of the composition was measured using a rotational viscometer at 23° C. [Hardness] The prepared ultraviolet-curable silicone composition was irradiated with ultraviolet light having a wavelength of 365 nm at a dose of 16,000 mJ / cm using an Eye UV electronic control device (model UBX0601-01) manufactured by Eye Graphics Co., Ltd. under a nitrogen atmosphere at room temperature (25° C.). 2 The sheet was irradiated with ultraviolet light so that the hardness of the cured product was 16,000 mJ / cm. The thickness of the sheet was 2.0 mm. The hardness of the obtained cured product was measured in accordance with JIS K6253-3:2012. [Mold Releasability] A dam was made between two glass plates using Teflon (registered trademark) tape to a thickness of 230 μm, and the prepared ultraviolet-curable silicone composition was placed inside the dam. Using an Eye UV electronic control device (model UBX0601-01) manufactured by Eye Graphics Co., Ltd., the composition was irradiated with ultraviolet light having a wavelength of 365 nm at a dose of 16,000 mJ / cm under a nitrogen atmosphere at room temperature (25°C). 2 The composition was cured by irradiating ultraviolet light so that the composition satisfies the following criteria: 0 (good), 1 (good), 2 (good), 3 (good), 4 (good), 5 (good), 6 (good), 7 (good), 8 (good), 9 (good), 10 (good), 11 (good), 12 (good), 13 (good), 14 (good), 15 (good), 16 (good), 17 (good), 18 (good), 19 (good), 20 (good), 21 (good), 22 (good), 23 (good), 24 (good), 25 (good), 26 (good), 27 (good), 28 (good), 29 (good), 30 (good), 31 (good), 32 (good), 33 (good), 34 (good), 35 (good), 36 (good), 37 (good), 38 (good), 40 (good),

[0060]

[0061] As shown in Table 1, the UV-curable silicone compositions prepared in Examples 1 to 5 have appropriate viscosities. Furthermore, the cured products have sufficient hardness and exhibit high releasability, making them extremely useful as replica mold materials. On the other hand, Comparative Example 1, which does not contain component (B), exhibits releasability but insufficient hardness. Furthermore, Comparative Example 2, in which component (A) was replaced with component (E), exhibited sufficient hardness but insufficient releasability.

Claims

1. (A) (a) a compound represented by the following general formula (1): (In the formula, R 1 each independently represents a monovalent hydrocarbon group having 1 to 20 carbon atoms; R 2 represents an oxygen atom or an alkylene group having 1 to 20 carbon atoms; R 3 are each independently an acryloyloxyalkyl group, a methacryloyloxyalkyl group, an acryloyloxyalkyloxy group, or a methacryloyloxyalkyloxy group, p is a number satisfying 0≦p≦10, and a is a number satisfying 1≦a≦3. 1 Rf 1 SiO 2 / 2 (R 1 has the same meaning as above, and Rf 1 (B) (c) an organopolysiloxane having a unit represented by the following general formula (2) or (2') below, in which 5% or more of the total number of monovalent organic groups bonded to silicon atoms are fluorine-substituted alkyl groups having 1 to 8 carbon atoms: (In the formula, R 6 each independently represents a monovalent hydrocarbon group having 1 to 20 carbon atoms; R 7 represents an oxygen atom or an alkylene group having 1 to 20 carbon atoms; R 8 are each independently an acryloyloxyalkyl group, a methacryloyloxyalkyl group, an acryloyloxyalkyloxy group, or a methacryloyloxyalkyloxy group, q is a number satisfying 0≦q≦10, and c is a number satisfying 1≦c≦3. 2 SiO 3 / 2 (Rf 2 represents a fluorine-substituted alkyl group having 1 to 8 carbon atoms bonded to a silicon atom, and in which 5% or more of the total number of monovalent organic groups bonded to silicon atoms are trifluoropropyl groups: 1 to 1,000 parts by mass of an organopolysiloxane resin; and (C) 0.01 to 20 parts by mass of a photopolymerization initiator.

2. An ultraviolet-curable silicone composition according to claim 1, which contains (D) a monofunctional (meth)acrylate compound not containing a siloxane structure in an amount of 1 to 1,000 parts by mass per 100 parts by mass of component (A).

3. A cured product of the ultraviolet-curable silicone composition according to claim 1 or 2.

4. The cured product according to claim 3, having a type D hardness of 30 or more as specified in JIS K6253-3:2012.

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