Active energy ray-curable silicone composition and cured product thereof

Abstract

(A) an organopolysiloxane resin having an alkenyl group in the molecule; (B) an organosiloxane oligomer having a viscosity at 25°C of 1,000 mPa s or less and having at least one silicon-bonded alkenyl group or silicon-bonded hydrogen atom and at least one silicon-bonded aryl group in the molecule; and (C) optionally, (C1) an organosiloxane oligomer having at least one alkenyl group in the molecule, and at least one silicon-bonded aryl group and SiO 4 / 2 The silicone composition is curable by active energy rays, comprising: (A) an organosilicon compound selected from the group consisting of an organopolysiloxane having no silicon-bonded aryl groups, (C2) an organopolysiloxane having at least one silicon-bonded hydrogen atom in the molecule and no silicon-bonded aryl groups, (C3) disilylbenzene, and mixtures thereof; (D) an organosilicon compound having at least one silicon-bonded acryloxyalkyl group or silicon-bonded methacryloxyalkyl group in the molecule, and at least one silicon-bonded hydrogen atom; and (E) a hydrosilylation reaction catalyst.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to and all benefits of U.S. Provisional Patent Application No. 63 / 334,824, filed April 26, 2022, the contents of which are incorporated herein by reference.

[0002] The present invention relates to an active energy ray-curable silicone composition and a cured product thereof. [Background technology]

[0003] Heat-curable, moisture-curable, or active energy ray-curable silicone compositions are used in a wide range of industrial fields because they cure to form cured products that are excellent in heat resistance, cold resistance, electrical insulation, weather resistance, water repellency, and transparency. In particular, the cured products are less likely to discolor than other organic materials, and the physical properties are less likely to deteriorate. Therefore, the cured products are suitable as optical materials.

[0004] For example, Patent Document 1 proposes a liquid silicone resin composition for optoelectronic devices that contains an alkenyl group-containing silicone resin, an organopolysiloxane that contains silicon-bonded hydrogen atoms, and a hydrosilylation reaction catalyst.

[0005] Meanwhile, in recent years, materials that are solid or semi-solid at room temperature have been proposed in the manufacturing process of optoelectronic devices. For example, silicone hot melt compositions have been reported. Such silicone hot melt compositions essentially consist of organosilicate (T) units (i.e., RSiO 3 / 2 units, where R represents a monovalent organic group such as methyl, phenyl, etc.) and / or silicate (Q) units (i.e., SiO 4 / 2 The main component is an organically modified polysilicate resin that is a non-fluid solid at room temperature and consists of (COO) units, and also contains a linear organopolysiloxane and a crosslinking agent.

[0006] For example, Patent Document 2 proposes an active energy ray curable hot melt silicone composition that contains a large amount (about 80% by weight) of an organic modified polysilicate resin (MQ resin), a linear organopolysiloxane, a mercapto-functional crosslinker, and a photoradical initiator, is solid or semi-solid at room temperature, and melts at high temperatures. Patent Document 3 proposes an addition curable adhesive silicone composition that contains a vinyl (Vi) group- and hydrosilyl (SiH) group-containing organopolysilicate resin (MT resin), and is solid or semi-solid in an uncured state at room temperature, and Patent Documents 4 and 5 propose a solvent-based hot melt composition that is prepared by subjecting a vinyl-containing organo-modified polysilicate resin and a hydrosilyl-modified linear polysiloxane to a metal catalyst pre-reaction in a solvent (such as toluene), and melting them and further crosslinking them with an additional multifunctional hydrosilyl crosslinker is carried out at high temperatures.

[0007] However, such non-flowable silicone hot melt compositions at room temperature or solvent-based flowable hot melt compositions are not suitable for producing hot melt films (or layers or sheets) because precise control of the temperature is required to melt the silicone hot melt composition and reduce the viscosity in order to obtain a uniform silicone hot melt film through the hot melt coating process, as well as to avoid premature curing (further hydrosilylation crosslinking) at high temperatures during the coating process. Furthermore, in the case of solvent-based silicone compositions, although suitable for the coating process, it is difficult to control the thickness and difficult to obtain a thick (200-500 μm) hot melt film due to inefficient solvent drying. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] US Patent Application Publication No. 2004 / 0116640(A1) [Patent Document 2] Same No. 2018 / 0305547(A1) [Patent Document 3] Same No. 2008 / 0308828(A1) [Patent Document 4] Same No. 2018 / 0208816(A1) [Patent Document 5] Same No. 2017 / 0355804(A1) Summary of the Invention [Problem to be solved by the invention]

[0009] An object of the present invention is to provide an active energy ray-curable silicone composition which has excellent handleability without the use of a solvent, which cures with heat to form a pre-cured product which has little tack or is non-tacky at room temperature and has excellent melt viscosity when heated, and which can be further cured with active energy rays to form a cured product which does not have hot-melt properties. [Means for solving the problem]

[0010] The active energy ray-curable silicone composition of the present invention comprises: (A) The average unit formula: (R 1 3SiO 1 / 2 ) a (R 2 R 1 2SiO 1 / 2 ) b (SiO 4 / 2 ) c (HO 1 / 2 ) d (In the formula, each R 1 are independently alkyl groups, R 2 is an alkenyl group, and the subscripts a, b, c, and d are numbers that satisfy the conditions a≧0, b>0, 0.3≦c≦0.7, 0≦d≦0.05, and a+b+c=1; (B) an organosiloxane oligomer having a viscosity at 25°C of 1,000 mPa s or less, selected from the group consisting of: (B1) an organosiloxane oligomer having at least one silicon-bonded alkenyl group and at least one silicon-bonded aryl group in the molecule; (B2) an organosiloxane oligomer having at least one silicon-bonded hydrogen atom and at least one silicon-bonded aryl group in the molecule; and a mixture of components (B1) and (B2); (C) Optionally, (C1) has at least one alkenyl group in the molecule, and a silicon-bonded aryl group and SiO 4 / 2 (C2) an organopolysiloxane having at least one silicon-bonded hydrogen atom in the molecule and having no silicon-bonded aryl groups; (C3) an organopolysiloxane having the following general formula: HR 1 2Si-C6H4-SiR 1 2H (In the formula, each R 1 wherein R is as defined above), and mixtures thereof; (D) an organosilicon compound having in the molecule at least one silicon-bonded acryloxyalkyl group or silicon-bonded methacryloxyalkyl group, and at least one silicon-bonded hydrogen atom; (E) a catalytic amount of a hydrosilylation reaction catalyst; Based on the total mass of components (A) to (C), the amount of component (A) is in the range of 50 to 80 mass%, the amount of component (B) is in the range of 5 to 40 mass%, and the amount of component (C) is in the range of 0 to 30 mass%, and the amount of component (D) is in the range of 2 to 20 parts by mass per 100 parts by mass of the total mass of components (A) to (C), with the proviso that the molar ratio of all silicon-bonded hydrogen atoms to all silicon-bonded alkenyl groups in components (A) to (D) is 0.5 or more and less than 1.0.

[0011] In various embodiments, component (B1) is 11 ) the following general formula: R 2 R 32SiO(R 3 2SiO) m SiR 3 2R 2 (In the formula, each R 2 are independently an alkenyl group, and each R 3 are independently an alkyl group or an aryl group, provided that at least one R 3 is an aryl group, and the subscript m is an integer of 0 to 10).

[0012] In various embodiments, component (B 11 ) is expressed by the following formula: (CH2=CH)(CH3)2SiO(C6H5)2SiOSi(CH3)2(CH=CH2), (CH2=CH)(CH3)2SiO(C6H5)(CH3)SiOSi(CH3)2(CH=CH2), and At least one organosiloxane oligomer is selected from organosiloxane oligomers represented by (CH2=CH)(CH3)(C6H5)SiOSi(CH3)(C6H5)(CH=CH2).

[0013] In various embodiments, component (B2) is 21 ) the following general formula: HR 3 2SiO(R 3 2SiO) m SiR 3 2H (In the formula, each R 3 are independently an alkyl group or an aryl group, provided that at least one R 3 is an aryl group, and the subscript m is an integer of 0 to 10).

[0014] In various embodiments, component (B 21 ) is expressed by the following formula: H(CH3)2SiO(C6H5)2SiOSi(CH3)2H, and At least one organosiloxane oligomer is selected from organosiloxane oligomers represented by H(CH3)2SiO(C6H5)(CH3)SiOSi(CH3)2H.

[0015] In various embodiments, component (D) has the following general formula:

[0016] [ka] (In the formula, R 4 is a methyl group or a hydrogen atom, R 5 is an alkylene group having 2 to 6 carbon atoms).

[0017] In various embodiments, component (D) has the following general formula:

[0018] [ka] (In the formula, each R 6 are independently an alkyl group or an aryl group, and X is represented by the following general formula:

[0019] [ka] (In the formula, R 4 is a methyl group or a hydrogen atom, R 5 is an alkylene group having 2 to 6 carbon atoms, wherein the subscript n is an integer from 1 to 10, the subscript n' is an integer from 1 to 10, and the subscript n'' is an integer from 0 to 10.

[0020] In various embodiments, component (D) is used in an amount such that the content of acryloxyalkyl groups or methacryloxyalkyl groups is 4 mmol / 100 g or more, based on the total weight of components (A)-(E), and optionally components (A)-(G) (components (F) and (G) are described below).

[0021] In various embodiments, the curable silicone composition further comprises (F) a hydrosilylation reaction inhibitor in an amount that modulates cure of the composition.

[0022] In various embodiments, the curable silicone composition further comprises (G) a photoradical initiator in an amount that promotes curing of the composition with actinic radiation.

[0023] The pre-cured product of the present invention can be obtained by subjecting the above-mentioned curable silicone composition to a hydrosilylation reaction.

[0024] The cured product of the present invention can be obtained by exposing the above-mentioned pre-cured product to active energy rays.

[0025] The method for producing the cured product of the present invention comprises the following steps: 1) curing the curable silicone composition of the present invention by a hydrosilylation reaction to form a pre-cured product; 2) placing the pre-cured material on a target substrate and applying heat and / or pressure to the pre-cured material placed on the target substrate; 3) exposing the pre-cured product to active energy rays. Effect of the Invention

[0026] The active energy ray-curable silicone composition of the present invention has excellent handleability at room temperature without using a solvent, and is cured by heat to form a pre-cured product that has little tack or is non-tacky at room temperature and has excellent melt viscosity when heated, and is further cured by active energy rays to form a cured product that does not have hot-melt properties.

[0027] definition The terms "comprising" or "comprise" are used herein in their broadest sense to mean and encompass the ideas of "including," "include," "consist(ing) essentially of," and "consist(ing) of." The use of "for example," "eg," "such as," and "including" to list examples does not limit the examples listed. Thus, "for example" or "such as" means "for example, but not limited to" or "such as, but not limited to," and encompasses other similar or equivalent examples. As used herein, the term "about" serves to reasonably encompass or describe slight variations in values ​​measured by instrumental analysis or as a result of handling samples. Such slight variations may be as much as ±0-25, ±0-10, ±0-5, or ±0-2.5% of the numerical value. Furthermore, the term "about" applies to both numerical values ​​when relating to a range of values. Furthermore, the term "about" may be applied to numerical values ​​even if not expressly stated.

[0028] It is to be understood that the appended claims are not limited to the specific compounds, compositions, or methods described therein for purposes of describing the "detailed description," and may vary among specific embodiments within the scope of the appended claims. With respect to any Markush group on which recitation of specific features or aspects of various embodiments is made herein, it should be understood that different, special, and / or unexpected results may be obtained from each element of the respective Markush group, independently of all other Markush elements. Each element of the Markush group may be relied upon individually and / or in combination to provide appropriate support for specific embodiments within the scope of the appended claims.

[0029] Any ranges and subranges relied upon in describing various embodiments of the present invention should also be understood to be within the scope of the appended claims, both individually and inclusively, and all ranges including integer and / or fractional values ​​are understood to be described and contemplated therein, even if not expressly written herein. Those skilled in the art will readily recognize that the recited ranges and subranges fully describe and enable various embodiments of the present invention, and that such ranges and subranges may be further delineated into relevant halves, thirds, fourths, fifths, etc. As merely an example, a range "from 0.1 to 0.9" may be further delineated into a lower third, i.e., 0.1 to 0.3, a middle third, i.e., 0.4 to 0.6, and an upper third, i.e., 0.7 to 0.9, which are individually and inclusively within the scope of the appended claims, and within which specific embodiments may be relied upon, individually and / or inclusively, to provide sufficient support. In addition, with respect to words defining or modifying a range, such as "at least," "greater than," "less than," "less than," etc., such words should be understood to include subranges and / or upper or lower limits. As another example, the range "at least 10" essentially includes subranges of at least 10 to 35, at least 10 to 25, 25 to 35, etc., each of which may be relied upon individually and / or collectively to provide sufficient support for specific embodiments within the scope of the appended claims. Finally, individual numbers within the disclosed ranges may be relied upon to provide sufficient support for specific embodiments within the scope of the appended claims. For example, the range "from 1 to 9" includes various individual integers, such as 3, as well as individual numbers including decimal points (or fractions), such as 4.1, which may be relied upon to provide sufficient support for specific embodiments within the scope of the appended claims.

[0030] The term "active energy rays" is used herein as ultraviolet rays, electron beams, radiation, etc. Examples of devices that emit ultraviolet rays include high pressure mercury lamps, medium pressure mercury lamps, ultraviolet LEDs, etc. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] The active energy ray-curable silicone composition of the present invention will now be described in detail.

[0032] Component (A) has the following average unit formula: (R 1 3SiO 1 / 2 ) a (R 2 R 1 2SiO 1 / 2 ) b (SiO 4 / 2 ) c (HO 1 / 2 ) d The organopolysiloxane resin is represented by the formula:

[0033] In the formula, each R 1 are independently an alkyl group. The alkyl group is exemplified by an alkyl group having 1 to 12 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a neopentyl group, a hexyl group, a cyclohexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, a undecyl group, and a dodecyl group. Among these, a methyl group is preferred.

[0034] In the formula, R 2 is an alkenyl group. The alkenyl group is exemplified by alkenyl groups having 2 to 12 carbon atoms, such as a vinyl group, an allyl group, a butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, a nonenyl group, a decenyl group, an undecenyl group, and a dodecenyl group. Among these, a vinyl group is preferred.

[0035] In the formula, the subscripts a, b, c, and d are numbers that satisfy the conditions: a≧0, b>0, 0.3≦c≦0.7, 0≦d≦0.05, and a+b+c=1, optionally 0.1≦a≦0.5, 0.01≦b≦0.2, 0.4≦c≦0.7, 0≦d≦0.05, and a+b+c=1, or optionally 0.2≦a≦0.5, 0.01≦b≦0.2, 0.4≦c≦0.7, 0≦d≦0.05, and a+b+c=1. This is because, if the subscripts a, b, c, and d are numbers within the above-mentioned ranges, the cured product obtained by curing the composition has appropriate hardness and mechanical strength.

[0036] The molecular weight of the organopolysiloxane resin of component (A) is not limited, but its number average molecular weight (Mn), measured by gel permeation chromatography (GPC) in terms of standard polystyrene, is preferably at least 1,500 g / mol, alternatively at least 2,000 g / mol, or alternatively at least 3,000 g / mol, while Mn is preferably not more than 6,000 g / mol, alternatively not more than 5,500 g / mol. The Mn of component (A) can be any range combining the upper and lower limits described above. It should be noted that when component (A) is in a solid state at 25°C and it is difficult to uniformly mix other components in the composition, this problem can be solved by preparing an organic solution of component (A) in advance, mixing it with some or all of components (B) and (C), and then removing the organic solvent used from this mixture. It should be noted that any organic solvent that can be used to prepare the organic solution of component (A) can be used as long as it can dissolve component (A) and can be easily removed. Specific examples include, but are not limited to, aromatic hydrocarbons such as toluene and xylene, and aliphatic hydrocarbons such as hexane and heptane.

[0037] Component (A) is used in an amount of 50-80% by weight, alternatively 55-80% by weight, or alternatively 55-75% by weight, based on the total weight of components (A)-(C). This is because, when the amount is equal to or greater than the lower limit of the above range, the cured product obtained by curing the composition has a less tacky or non-tacky surface and suitable hardness and mechanical strength, while when the amount is equal to or less than the upper limit of the above range, the composition has a suitable viscosity at 25°C.

[0038] Component (B) is an organosiloxane oligomer for imparting flow properties to the curable silicone composition and hot melt properties to the cured product obtained by curing the composition. The molecular structure of the organosiloxane oligomer of component (B) is not limited, but is exemplified by a linear structure and a partially branched linear structure. Component (B) may be one of the organosiloxane oligomers having these molecular structures, or may be a mixture of two or more organosilicon compounds having these molecular structures. The molecular weight of the organosiloxane oligomer of component (B) is not limited, but is preferably 2,000 g / mol or less, alternatively 1,500 g / mol or less. The organosiloxane oligomer typically has a viscosity at 25°C of 1,000 mPa·s or less, alternatively 500 mPa·s or less, or alternatively 100 mPa·s or less. It should be noted that in this specification, viscosity is a value measured at 23±2° C. using a Brookfield viscometer according to ASTM D1084.

[0039] The organosiloxane oligomer of component (B) also acts as a chain extender or crosslinker for the composition and is selected from (B1) an organosiloxane oligomer having at least one silicon-bonded alkenyl group and at least one silicon-bonded aryl group in the molecule, (B2) an organosiloxane oligomer having at least one silicon-bonded hydrogen atom and at least one silicon-bonded aryl group in the molecule, and a mixture of components (B1) and (B2).

[0040] The organosiloxane oligomer of component (B1) typically has the following general formula: R 2 R 3 2SiO(R 3 2SiO) m SiR 3 2R 2 It is an organosiloxane oligomer represented by the formula:

[0041] In the formula, each R 2 are each independently an alkenyl group, examples of which include the same groups as those mentioned above. Among these, a vinyl group is preferred.

[0042] In the formula, each R 3 R is independently an alkyl group or an aryl group. 3 Examples of alkyl groups include the above R 1 The alkyl groups are the same as those shown in R 3 Examples of the aryl group include aryl groups having 6 to 12 carbon atoms, such as phenyl, tolyl, xylyl, and naphthyl groups. However, at least one R 3 is an aryl group, typically a phenyl group.

[0043] In the formula, the subscript m is an integer from 0 to 10, alternatively an integer from 0 to 5, alternatively an integer from 0 to 3, or alternatively an integer of 0 or 1.

[0044] Component (B1) typically has the following formula: (CH2=CH)(CH3)2SiO(C6H5)2SiOSi(CH3)2(CH=CH2), (CH2=CH)(CH3)2SiO(C6H5)(CH3)SiOSi(CH3)2(CH=CH2), and At least one organosiloxane oligomer is selected from organosiloxane oligomers represented by (CH2=CH)(CH3)(C6H5)SiOSi(CH3)(C6H5)2(CH=CH2).

[0045] The organosiloxane oligomer of component (B2) typically has the following general formula: HR 3 2SiO(R 3 2SiO) m SiR 3 It is an organosiloxane oligomer represented by 2H.

[0046] In the formula, each R 3 is an alkyl or aryl group, examples of which include the same groups as above. However, at least one R 3 is an aryl group, typically a phenyl group.

[0047] In the formula, the subscript m is an integer from 0 to 10, alternatively an integer from 0 to 5, alternatively an integer from 0 to 3, or alternatively an integer of 0 or 1.

[0048] Component (B2) typically has the following formula: H(CH3)2SiO(C6H5)2SiOSi(CH3)2H, and At least one organosiloxane oligomer is selected from organosiloxane oligomers represented by H(CH3)2SiO(C6H5)(CH3)SiOSi(CH3)2H.

[0049] Component (B) is used in an amount of 5-40% by weight, alternatively 10-35% by weight, or alternatively 20-35% by weight, based on the total weight of components (A)-(C). This is because, when the amount is equal to or greater than the lower limit of the above range, the composition has good handleability and the cured product obtained by curing the composition has a less sticky or non-sticky surface, while when the amount is equal to or less than the upper limit of the above range, the cured product obtained has good transparency. The organosiloxane oligomer of component (B) may be a mixture of components (B1) and (B2). The amounts of components (B1) and (B2) are not limited, but the amount of component (B) should be such that the molar ratio of all silicon-bonded hydrogen atoms to all silicon-bonded alkenyl groups in components (A)-(D) is 0.5 or more and less than 1.0.

[0050] Component (C) is an optional component, which has at least one alkenyl group in the (C1) molecule, and has silicon-bonded aryl groups and SiO 4 / 2 (C2) an organopolysiloxane having at least one silicon-bonded hydrogen atom in the molecule and having no silicon-bonded aryl groups; (C3) an organopolysiloxane having the following general formula: HR 1 2Si-C6H4-SiR 1 2H and mixtures thereof. 1 is as stated above.

[0051] When the mixture of components (A) and (B) can be completely cured, the addition of component (C) is optional. However, when the mixture cannot be cured due to a lack of silicon-bonded alkenyl groups, component (C1) should be added, and when the mixture cannot be cured due to a lack of silicon-bonded hydrogen atoms, component (C2) and / or (C3) should be added. Furthermore, when the cured product obtained by curing the composition is hard, component (C) should be added as a chain extender, and when the cured product obtained by curing the composition is soft, component (C) should be added as a crosslinker.

[0052] Component (C1) has at least one alkenyl group in the molecule, and has silicon-bonded aryl groups and SiO 4 / 2It is an organopolysiloxane having no unit. Examples of the alkenyl group include alkenyl groups having 2 to 12 carbon atoms, such as vinyl, allyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, and dodecenyl. Among these, vinyl is preferred. Examples of groups bonded to silicon atoms other than alkenyl groups in component (C1) include alkyl groups having 1 to 12 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, neopentyl, hexyl, cyclohexyl, heptyl, octyl, nonyl, decyl, undecyl, and dodecyl.

[0053] The molecular structure of component (C1) is not limited, but is typically a linear structure, a partially branched linear structure, a branched structure, or a cyclic structure. Component (C1) may be one organopolysiloxane having these molecular structures, or may be a mixture of two or more organopolysiloxanes having these molecular structures.

[0054] Examples of such component (C1) include dimethylpolysiloxanes whose molecular chain ends are capped with dimethylvinylsiloxy groups, copolymers of dimethylsiloxanes whose molecular chain ends are capped with dimethylvinylsiloxy groups and methylvinylsiloxanes, copolymers of dimethylsiloxanes whose molecular chain ends are capped with trimethylsiloxy groups and methylvinylsiloxanes, and mixtures of two or more of these.

[0055] Component (C2) is an organopolysiloxane having at least one silicon-bonded hydrogen atom in the molecule and no silicon-bonded aryl group. Examples of the group bonded to the silicon atom in component (C2) include alkyl groups having 1 to 12 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, neopentyl, hexyl, cyclohexyl, heptyl, octyl, nonyl, decyl, undecyl, and dodecyl groups.

[0056] The molecular structure of component (C2) is not limited, but is typically a linear structure, a partially branched linear structure, a branched structure, a cyclic structure, or a three-dimensional network structure. Component (C2) may be one organopolysiloxane having these molecular structures, or may be a mixture of two or more organopolysiloxanes having these molecular structures.

[0057] Examples of such component (C2) include methylhydrogenpolysiloxane capped at both molecular chain ends with trimethylsiloxy groups, a copolymer of dimethylsiloxane and methylhydrogensiloxane capped at both molecular chain ends with trimethylsiloxy groups, dimethylpolysiloxane capped at both molecular chain ends with dimethylhydrogensiloxy groups, a copolymer of dimethylsiloxane and methylhydrogensiloxane capped at both molecular chain ends with dimethylhydrogensiloxy groups, (CH3)2HSiO 1 / 2 Units and SiO 4 / 2 A copolymer consisting of the units (CH3)2HSiO 1 / 2 Unit: (CH3)3HSiO 1 / 2 Units and SiO 4 / 2 units, as well as mixtures of two or more of these.

[0058] Component (C3) has the following general formula: HR 1 2Si-C6H4-SiR 1 2H (In the formula, each R 1is as above).

[0059] An example of such a component (C3) is the following disilylbenzene: H(CH3)2Si-C6H4-Si(CH3)2H, and H(CH3)(C2H5)Si-C6H4-Si(CH3)(C2H5)H

[0060] The organosilicon compound of component (C) may be a mixture of components (C1) and (C2). However, component (C) typically has a viscosity of 1,000 mPa·s or less, alternatively 500 mPa·s or less, or alternatively 100 mPa·s or less at 25° C. It should be noted that viscosity herein is measured at 23±2° C. using a Brookfield viscometer according to ASTM D1084.

[0061] Component (C) is used in an amount of 0-30% by weight, alternatively 0-20% by weight, or alternatively 0-10% by weight, based on the total weight of components (A)-(C). This is because when the amount is equal to or greater than the lower limit of the above range, the composition has good handleability, while when the amount is equal to or less than the upper limit of the above range, the composition has good transparency. The organosilicon compound of component (C) may be a mixture of components (C1)-(C3). The amounts of components (C1)-(C3) are not limited, but the amount of component (C) should be such that the molar ratio of all silicon-bonded hydrogen atoms to all silicon-bonded alkenyl groups in components (A)-(D) is 0.5 or more and less than 1.0.

[0062] The molar ratio of all silicon-bonded hydrogen atoms to all silicon-bonded alkenyl groups in components (A) to (D) ("SiH / Vi ratio") is equal to or greater than 0.5 and less than 1.0, alternatively in the range of 0.5 to 0.95, or alternatively in the range of 0.6 to 0.9. This is because, when the molar ratio is equal to or greater than the lower limit of the above range, the composition can be completely cured, and the cured product obtained by curing the composition has an appropriate hardness and a less sticky or non-sticky surface, while when the molar ratio is equal to or less than the upper limit of the above range, the cured product has good hot melt properties.

[0063] Component (D) is an organosilicon compound having at least one silicon-bonded acryloxyalkyl group or silicon-bonded methacryloxyalkyl group and at least one silicon-bonded hydrogen atom in the molecule, and is added to the composition described herein for the purpose of, for example, sufficiently crosslinking the cured product obtained by the hydrosilylation reaction and rendering it conformable to a substrate by the application of active energy rays or the like.

[0064] The acryloxyalkyl group or methacryloxyalkyl group in component (D) is not limited, but is typically an acryloxyalkyl group or methacryloxyalkyl group represented by the following general formula:

[0065] [ka]

[0066] In the formula, R 4 is a methyl group or a hydrogen atom.

[0067] In the formula, R 5 is an alkylene group having 2 to 6 carbon atoms. Examples of the alkylene group include an ethylene group, a propylene group, a methylethylene group, a butylene group, a pentylene group, and a hexylene group. Among these, a propylene group is preferred.

[0068] The silicon-bonded organic groups other than acryloxyalkyl groups and methacryloxyalkyl groups in component (D) are exemplified by, but not limited to, alkyl groups having 1 to 12 carbon atoms, such as methyl groups, ethyl groups, propyl groups, isopropyl groups, butyl groups, isobutyl groups, tert-butyl groups, pentyl groups, neopentyl groups, hexyl groups, cyclohexyl groups, heptyl groups, octyl groups, nonyl groups, decyl groups, undecyl groups, and dodecyl groups; aryl groups having 6 to 12 carbon atoms, such as phenyl groups, tolyl groups, xylyl groups, and naphthyl groups; and aralkyl groups having 7 to 12 carbon atoms, such as benzyl groups and phenethyl groups. Among these, methyl groups are preferred.

[0069] The molecular structure of component (D) is not limited, but is typically a linear structure, a partially branched linear structure, a branched structure, a cyclic structure, or a three-dimensional network structure. Component (D) may be one of the organosilicon compounds having these molecular structures, or may be a mixture of two or more organosilicon compounds having these molecular structures.

[0070] Examples of component (D) include organosilicon compounds represented by the following formula:

[0071] [ka]

[0072] In the formula, each R 6 are independently an alkyl group or an aryl group, examples of which include the same groups as those described above.

[0073] In the formula, each X is an acryloxyalkyl group or a methacryloxyalkyl group, examples of which include the same groups as those described above.

[0074] In the formula, the subscript n is an integer from 1 to 10, the subscript n' is an integer from 1 to 10, and the subscript n'' is an integer from 0 to 10.

[0075] Examples of component (D) include organosilicon compounds represented by the following formula:

[0076] [ka]

[0077] [ka]

[0078] Methods for preparing component (D) are well known in the art, as exemplified in U.S. Pat. Nos. 4,554,339, 5,256,754, 5,334,796, and 9,018,332, and U.S. Patent Application Publication Nos. 2021 / 0122769 and 2014 / 0203323.

[0079] Component (D) is used in an amount of 2 to 20 parts by weight, alternatively 4 to 20 parts by weight, per 100 parts by weight of the total weight of components (A) to (C), because when the amount is equal to or greater than the lower limit of the above range, the composition has good curability with active energy rays, whereas when the amount is equal to or less than the upper limit of the above range, the composition has good stability.

[0080] Since the content of acryloxyalkyl or methacryloxyalkyl groups (hereinafter referred to as "(meth)acrylic content") varies depending on the molecular structure of component (D), it is recommended that the (meth)acrylic content be 4 mmol / 100 g or more, alternatively 8 mmol / 100 g or more, alternatively 10 mmol / 100 g or more, based on the total mass of components (A) to (E), and optionally components (A) to (F) or components (A) to (G) (i.e., in an embodiment in which component (F) and / or component (G) are used together with components (A) to (E)). This is because, if the amount is equal to or more than the lower limit of the above range, the composition has good curability by active energy rays and good high-temperature stability. On the other hand, a larger (meth)acrylic content is preferable for better ultraviolet curability, so the upper limit is not limited. However, it is typically 60 mmol / 100 g or less.

[0081] Component (E) is a hydrosilylation catalyst used to accelerate the curing of the composition. Component (E) hydrosilylation catalysts are well known in the art and commercially available. Suitable hydrosilylation catalysts include, but are not limited to, platinum group metals, including platinum, rhodium, ruthenium, palladium, osmium or iridium metals, or organometallic compounds thereof, and combinations of any two or more thereof. Component (E) is typically a platinum-based catalyst that can dramatically accelerate the curing of the composition. Examples of platinum-based catalysts include platinum fine powder, chloroplatinic acid, alcoholic solutions of chloroplatinic acid, platinum-alkenylsiloxane complexes, platinum-olefin complexes, and platinum-carbonyl complexes, with platinum-alkenylsiloxane complexes being the most typical.

[0082] In various embodiments, component (E) is a hydrosilylation reaction catalyst comprising a complex of platinum with a low molecular weight organopolysiloxane, including a complex of platinum with 1,3-divinyl-1,1,3,3-tetramethyldisiloxane. These complexes may be microencapsulated in a resin matrix. In a specific embodiment, the catalyst includes a complex of platinum with 1,3-divinyl-1,1,3,3-tetramethyldisiloxane.

[0083] Examples of hydrosilylation catalysts suitable for component (E) are described in, for example, U.S. Patent Nos. 3,159,601, 3,220,972, 3,296,291, 3,419,593, 3,516,946, 3,814,730, 3,989,668, 4,784,879, 5,036,117 and 5,175,325, and European Patent No. 0347895(B). Microencapsulated hydrosilylation catalysts and their preparation methods are exemplified in U.S. Patent Nos. 4,766,176 and 5,017,654.

[0084] The amount of component (E) in the composition is an amount effective for promoting the curing of the composition. Specifically, in order to sufficiently cure the composition, the content of component (E) is typically an amount such that the content of the catalytic metal in component (E) relative to the composition is about 0.01 to about 500 ppm, alternatively about 0.01 to about 100 ppm, alternatively about 0.01 to about 50 ppm, alternatively about 0.1 to about 10 ppm, calculated as a mass unit.

[0085] In various embodiments, the active energy radiation-curable silicone composition includes (F) a hydrosilylation reaction inhibitor to control the cure rate of the curable silicone composition. In certain embodiments, component (F) includes, but is not limited to, an alkyne alcohol such as 2-methyl-3-butyn-2-ol, 3,5-dimethyl-1-hexyn-3-ol, 2-phenyl-3-butyn-2-ol, or 1-ethynyl-cyclohexan-1-ol; an ene-yne ​​compound such as 3-methyl-3-penten-1-yne, or 3,5-dimethyl-3-hexen-1-yne; or 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetrahexenylcyclotetrasiloxane, tris[(1,1-dimethyl-2-propynyl)oxy]methylsilane, diallylmaleate, or benzotriazole, and component (E) can be incorporated into the composition as an optional component.

[0086] The amount of component (F) in the composition is not particularly limited, but when contained, it is typically about 1 to about 10,000 ppm, alternatively about 10 to about 5,000 ppm, in terms of mass units for the composition. This is because, when the amount of component (F) is equal to or greater than the lower limit of the above range, the storage stability of the composition is good, whereas, when the amount of component (F) is equal to or less than the upper limit of the above range, the curability of the composition at low temperatures is good.

[0087] In various embodiments, the active energy radiation curable silicone composition comprises component (G) a photoradical initiator to promote the curing of the composition by active energy radiation. Examples of photoradical initiators include acetophenone, propiophenone, benzophenone, 2-hydroxy-2-methylpropiophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxycyclohexyl phenyl ketone, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one, 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-(4-morpholinophenyl)-butanone-1, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]phenyl] ... ]-1-[4-(4-morpholinyl)phenyl]-1-butanone, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 1,2-octanedione, 1-[4-(phenylthio)-2-(O-benzoyloxime)]ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-1-(O-acetyloxime), ethyl-4-dimethylaminobenzoate, 2-ethylhexyl-4-dimethylaminobenzoate, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide, benzoyl peroxide, cumene peroxide, and mixtures of two or more thereof.

[0088] The amount of component (G) in the present composition is an amount effective for curing and irradiating the present composition with active energy rays, and is preferably within the range of 0.1 to 15 parts by mass, or alternatively, more preferably within the range of 0.1 to 10 parts by mass, relative to 100 parts by mass of the total amount of components (A) to (C). This is because, when the content of component (G) is equal to or more than the lower limit of the above range, the obtained composition can be sufficiently cured, whereas, when the content is equal to or less than the upper limit of the above range, the heat resistance and light resistance of the obtained cured product are improved.

[0089] In various embodiments, the active energy radiation curable silicone composition includes a free radical scavenger (scavenger) that can be optionally used to control or inhibit the radical reaction of the active energy radiation curable silicone composition. Since the active energy radiation curable silicone composition includes component (D), a viable free radical scavenger may be present, for example, to prevent premature reaction during storage and use of the active energy radiation reactive hot melt film prepared using the composition. Scavengers including phenolic compounds are one class of such materials that can be used in the present invention, including, for example, 4-methoxyphenol (MEHQ, methyl ether of hydroquinone), hydroquinone, 2-methylhydroquinone, 2-t-butylhydroquinone, t-butylcatechol, butylated hydroxytoluene, and butylated hydroxyanisole, and combinations of two or more thereof. Other scavengers that can be used include phenothiazine and oxygen-free inhibitors, such as NPAL type inhibitors (tris-(N-nitroso-N-phenylhydroxylamine) aluminum salts) from Albemarle Corporation (Baton Rouge, La). Alternatively, the free radical scavenger may be selected from the group consisting of phenolic compounds, phenothiazines, and anoxic inhibitors. Free radical scavengers are known, for example, from U.S. Patent No. 9,475,968, and are commercially available.

[0090] The amount of scavenger in the active energy ray-curable silicone composition will depend on a variety of factors including the type and amount of component (D), but the scavenger may be present in an amount from 1 to 5,000 ppm by weight, alternatively from 10 to 1,000 ppm by weight, or alternatively from 50 to 500 ppm by weight, based on 100 weight of the composition.

[0091] The viscosity of the composition at 25° C. is not limited, but is typically in the range of 100 to 100,000 mPa·s.

[0092] Next, the pre-cured product and the cured product of the present invention will be described in detail.

[0093] The pre-cured product of the present invention is obtained by subjecting the above-mentioned curable silicone composition to a hydrosilylation reaction. The term "pre-cured" refers to a state in which a crosslinked but not completely crosslinked network is present (a state having intermediate physical properties between an uncured product and a completely cured product). The pre-cured product may have a less tacky or non-tacky surface. In particular, the storage modulus G' of the cured product at 20°C is not limited, but is typically in the range of 0.05 to 15 MPa, alternatively in the range of 0.07 to 10 MPa, or alternatively in the range of 0.1 to 5 MPa, under the conditions of frequency = 1 Hz and strain = 1%. The melt viscosity of the pre-cured product at 100°C is not limited, but is typically in the range of 1 to 5000 Pa·s.

[0094] Next, the above-mentioned preliminary cured product is irradiated with active energy rays to obtain the cured product of the present invention. Examples of active energy rays used to cure the preliminary cured product include ultraviolet light and visible light, and light having a wavelength in the range of 250 to 500 nm is preferred. This is because excellent curability is obtained and the cured product is not decomposed by active energy rays.

[0095] The cured product is typically optically transparent. This is preferably because optical transparency is desirable for high performance when the cured product is used in an optical device or image display. The form of the cured product is not limited and can be in the form of a sheet, film, lens, or block. The cured product can be combined with various substrates. The cured product is typically laminated between the same substrate or different substrates, particularly between the same substrate or different substrates in an optical device.

[0096] The state of the cured product is not limited, but is preferably an elastomer. In particular, the storage modulus G' of the cured product at 20°C is not limited, but is typically in the range of 0.05 to 20 MPa, alternatively in the range of 0.07 to 15 MPa, or alternatively in the range of 0.1 to 10 MPa, under the conditions of frequency = 1 Hz and strain = 1%. This is because when the cured product is within the above range, good bonding strength against deformation and good flexibility against material breakage are obtained. In general, the cured product no longer has hot melt properties.

[0097] The method for producing the cured product is as follows: 1) curing the curable silicone composition of the present invention by a hydrosilylation reaction to form a pre-cured product; 2) placing the pre-cured material on a target substrate and applying heat and / or pressure to the pre-cured material placed on the target substrate; 3) exposing the pre-cured product to active energy rays, but is not limited thereto.

[0098] In step 1), the curable silicone composition is heated to form a pre-cured product of a desired shape by hydrosilylation reaction. Typically, the curing speed can be controlled by the amount and ratio of components (E) and (F), and the temperature can be room temperature to 180°C, preferably 80°C to 150°C. The shape of the pre-cured product is not limited, but it is preferably in the form of a sheet, film, lens, or block. The pre-cured product contains free (meth)acrylic groups, which can be analyzed by Fourier Transform-Infrared (FT-IR) spectroscopy as shown in: "UV coatings: basics, recent developments and new applications", at page 33 (Elsevier; 2006 Dec 21) and Schwalm; Polymer Chemistry. 2013; 4(8): 2449-56 to Espeel.

[0099] In step 2), since the pre-cured product has thermoplastic and hot melt properties, the pre-cured product is deformed or melted by heating and / or pressure to conform to the target substrate. Typically, the temperature can be up to 150°C, preferably up to 100°C. When applying pressure to the pre-cured product to conform to the target substrate, the applied pressure can be generally 0.05 MPa or more, alternatively 0.1 MPa or more, and 2 MPa or less, alternatively 1 MPa or less. In order to completely remove voids (to obtain a bubble-free laminate), a vacuum can be applied during lamination, generally 25 Torr or less, alternatively 5 Torr or less, depending on the complexity of the three-dimensional features of the target surface.

[0100] In step 3), the pre-cured product is exposed to active energy rays (e.g., by a UV LED lamp) to form a cured product without changing its shape. UV curing is performed by UV irradiation, but the source of the UV light is generally not important as long as the irradiation lamp emits light rays close to UV light. Typically, UV LED lamps are generally used to precisely control the curing speed. Typical wavelengths of UV LED lamps are 365 nm, 385 nm, 395 nm, and 405 nm. Preferably, 365 nm and 395 nm are generally used. The irradiation dose is preferably 0.1 to 200 J / cm. 2 or optionally within the range of 1 to 100 J / cm 2 The ultraviolet irradiation is usually performed in the atmosphere. If necessary, in order to prevent oxygen inhibition on the surface, the pre-cured product may be irradiated with ultraviolet rays while laminated with a transparent or semi-transparent substrate, such as a polyethylene terephthalate film and glass. Alternatively, the pre-cured product may be irradiated with ultraviolet rays in an environment of a gas that does not cause curing inhibition, such as nitrogen and carbon dioxide.

[0101] This pre-cured product is useful for use in electronic devices, optical devices, or image display devices as a laminate on various target substrates having not only flat surfaces but also uneven surfaces, and for obtaining a laminated cured product by ultraviolet irradiation. The electronic device is, for example, a semiconductor device. Examples of semiconductor devices include semiconductor packages such as ball grid array (BGA) packages, pin grid array (PGA) packages, and land grid array (LGA). The optical device is, for example, an optical semiconductor device. Examples of optical semiconductor devices include light emitting diodes (LEDs), photocouplers, and charge-coupled devices (CCDs). Furthermore, light emitting diode (LED) elements and solid-state image sensors are shown as optical semiconductor elements. In particular, the curable silicone composition of the present invention can be suitably used even when sealing together so-called micro LEDs (mini LEDs) having a structure in which a large number of small LED elements are arranged on a substrate. Furthermore, since the curable silicone composition of the present invention has excellent heat resistance and moisture resistance, transparency is unlikely to decrease and turbidity is hardly caused. This has the advantage that the light extraction efficiency of the optical semiconductor device including the micro LED can be maintained at a good level. EXAMPLES

[0102] The active energy ray-curable silicone composition and the cured product of the present invention are described in detail below using examples and comparative examples. However, the present invention is not limited to the description of the examples listed below.

[0103] [Gel Permeation Chromatography (GPC)] GPC data for component (a1) was collected using a Waters 2695 separation module equipped with a Waters 2414 refractive index detector (RID). Three (7.8 x 300 mm) Styragel HR columns (molecular weight separation range 100-4,000,000) and one Styragel guard column (4.6 x 30 mm) with toluene were used. Samples were prepared as 0.5 wt% solutions in toluene and filtered through 0.45 micron PTFE syringe filters. A flow rate of 1 milliliter per minute was used, with detector and column temperatures of 45°C, injection volume of 100 microliters, and run time of 60 minutes. Number average molecular weights (Mn) were calculated against linear polystyrene standards covering a molecular weight range of 580-2,610,000.

[0104] [viscosity] The viscosity of each organosiloxane oligomer at 25°C was measured by a DV1 VISCOMETER (Brookfield) using spindle #CPA-40Z. The active energy ray curable silicone composition was measured by a HADV III VISCOMETER (Brookfield) using spindle #CP-25. The viscosity was measured for 2 minutes, and the torque was controlled in the range of 20 to 80%. The final data was collected after the measurement was completed.

[0105] [Degree of stickiness] Samples of the active energy radiation curable silicone composition were cured and the degree of tackiness was evaluated as follows: Each sample prepared as above was poured into an aluminum dish and the sample was cured by heating the sample at 120°C for 30 minutes and cooled to room temperature. If the sample does not stick to the finger, the sample is considered "non-tacky". If the sample sticks to the finger, the sample is considered "tacky".

[0106] [Melt Viscosity] The melting behavior of the resulting silicone hot melt, obtained by curing the active energy radiation curable silicone composition at 120°C for 30 minutes, could be observed by exposing a solid sample to 100°C. "Melted" means that the shape of the sample collapses and spreads onto the substrate. "Does not melt" means that the shape of the sample is maintained. If the sample does not melt at high temperature, the melt viscosity cannot be measured because the sample is fully crosslinked. To measure the melt viscosity, the hot melt sample was prepared in the same manner as above and the sample was placed on a rheometer (ARES-G2, TA Instruments) in parallel plate geometry (25 mm). The melt viscosity was then collected at 100°C at a fixed shear rate of 1 1 / s and a gap of 300 μm.

[0107] [Storage modulus and loss modulus] Samples of the active energy radiation curable silicone composition were cured, and the shear modulus of the resulting silicone hot melt was evaluated as follows. Each sample prepared as above was poured into a mold (thickness=1 mm) and sandwiched between release films. The assembled sample was cured by heating at 120°C for 30 minutes. After cooling and removing the release film, the sample was placed on a rheometer (ARES-G2, TA Instruments) with parallel plate geometry (25 mm). Dynamic storage modulus (G') was then collected at 20°C and 100°C with a fixed frequency of 1 Hz, using a strain of 0.5%, a gap of 300 μm, and a normal force of 0 N.

[0108] For post-UV property measurements, the above assembled samples were cured by heating at 120°C for 30 min, followed by exposure to UV light to promote the photoradical crosslinking reaction. The UV irradiation conditions were a 365 nm LED lamp (FireJet™ FJ100) from the top of the film with a UV irradiance of 10 J / cm. 2 UV light was irradiated.

[0109] [Examples 1 to 8 and Comparative Examples 1 to 7] The following components were mixed uniformly in the amounts shown in Table 1 to produce active energy ray-curable silicone compositions. When component (A) was solid at 25°C, it had a high viscosity, so component (A) was added to the other components using a solvent such as toluene or xylene. Then, to prepare a solventless composition, the solvent was evaporated and replaced with other components that facilitate mixing. For example, component (B) was first added to a solution of component (A) dissolved in a solvent. Then, the solvent was removed under reduced pressure by heating while bubbling with nitrogen. After cooling to room temperature, component (C) was added. The mixture was mixed at room temperature. Furthermore, other components were added to the mixture and mixed at room temperature. The resulting compositions and cured products were evaluated as described above. These results are shown in Table 1. The "SiH / Vi ratio" in each of Table 1 indicates the molar ratio of all silicon-bonded hydrogen atoms to all silicon-bonded vinyl groups in components (A) to (D). Furthermore, in each of Table 1, "(meth)acrylic content" indicates the content of methacryloxypropyl groups relative to the total mass of components (A) to (G).

[0110] The following organopolysiloxane resins were used as component (A): (a1): The average unit formula: [(CH3)3SiO 1 / 2 ] 0.40 [(CH2=CH)(CH3)2SiO 1 / 2 ] 0.04 (SiO 4 / 2 ) 0.56 The organopolysiloxane resin has a vinyl group content of about 1.9% by mass, a number average molecular weight (Mn) of about 5,000, and is solid at 25° C.

[0111] The following organosiloxane oligomers were used as component (B): (b1): the following formula: (CH2=CH)(CH3)2SiO(C6H5)2SiOSi(CH3)2(CH=CH2) The organosiloxane oligomer has a viscosity of 8.7 mPa·s and a vinyl group content of approximately 14.06% by mass. (b2): the following formula: H(CH3)2SiO(C6H5)2SiOSi(CH3)2H having a viscosity of 4.4 mPa s and a silicon-bonded hydrogen atom content of approximately 0.61 mass%.

[0112] The following organopolysiloxanes or disilylbenzenes were used as component (C): (c1): the following formula: (CH2=CH)(CH3)2SiO[(CH3)2SiO]7Si(CH3)2(CH=CH2) , has a viscosity of 7 mPa·s, and has a vinyl group content of approximately 7.49% by mass. (c2): 1,4-bis(dimethylsilyl)benzene (c3): the following formula: H(CH3)2SiO[(CH3)2SiO] 16 Si(CH3)2H Organopolysiloxane having a viscosity of 15 mPa s and a content of silicon-bonded hydrogen atoms of approximately 0.15 mass %.

[0113] The following organosilicon compounds were used as component (D): (d1): The following formula:

[0114] [ka] The organotrisiloxane has a methacrylic content of 313.0 mmol / 100 g and a silicon-bonded hydrogen atom content of approximately 0.63 mass %. (d2): The following formula:

[0115] [ka] The organodisiloxane has a methacrylic content of 385.0 mmol / 100 g and a silicon-bonded hydrogen atom content of approximately 0.38 mass %. (d3): The following formula:

[0116] [ka] having a methacrylic content of 81.6 mmol / 100 g and a silicon-bonded hydrogen atom content of approximately 0.086 mass %. (d4): The following formula:

[0117] [ka] having a methacrylic content of 151.2 mmol / 100 g and a silicon-bonded hydrogen atom content of approximately 0.076 mass %.

[0118] The following hydrosilylation reaction catalyst was used as component (E): (e1): Complex of platinum with 1,3-divinyl-1,1,3,3-tetramethyldisiloxane in 1,3-divinyl-1,1,3,3-tetramethyldisiloxane solution (platinum content = 4% by mass)

[0119] The following hydrosilylation inhibitors were used as component (F): (f1): 1-ethynyl-cyclohexan-1-ol

[0120] The following photoradical initiators were used as component (G): (g1): 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1 (g2): 1-hydroxycyclohexyl phenyl ketone

[0121] [Table 1]

[0122] [Table 2]

[0123] [Table 3]

[0124] [Table 4]

[0125] Examples 1 to 8 are representative examples of active energy ray-curable silicone compositions that contain components (A) to (G) and provide a flowable liquid in the range of 300 to 30,000 mPa s at 25° C. After thermal curing (hydrosilylation reaction), the curable silicone compositions are solid or semi-solid at room temperature and have a viscosity of 9×10 at 20° C. 4 It provides a non-tacky surface with a relatively high storage modulus (G') of more than 10 Pa, and a significant storage modulus drop (melting) behavior at high temperatures such as 100°C. Upon exposure to high temperatures, the heat-cured silicone composition in the solid state is converted into a flowable liquid with a rotational viscosity in the range of 70 to 1,300 Pa·s (at 100°C). Upon UV irradiation after heat curing, further crosslinking occurs via a radical reaction of the free methacrylic groups (from component (D)) initiated by the photoradical initiator (G), which is fully compatible. Thus, further crosslinking by UV can reach 1×10 at 100°C. 4 It promotes an increase in storage modulus over 1 Pa, and finally shows high temperature stability without deformation. In addition, it shows good transparency in the visible range.

[0126] In contrast, Comparative Examples 1 to 7, despite containing all of the components (A) to (G) used in Examples 1 to 8, exhibit properties undesirable for use in the industrial field, such as a sticky surface and no hot melt properties. Comparative Examples 1 to 7 show that the cured products have a sticky surface and therefore a high modulus hot melt base cannot be prepared (after heat curing). Comparative Examples 3 and 6 show that the cured products do not have hot melt behavior (do not melt) (after heat curing) and therefore a hot melt base cannot be prepared. Comparing Comparative Example 1 with Examples 2 to 4, Comparative Example 1, which contains a relatively small amount of component (A) (51.9%), exhibits a high modulus of elasticity of 2×10 after heat curing. 4 It provides a tacky surface with a lower storage modulus of less than 2×10 Pa. Comparing Comparative Examples 2-3 with Examples 1-8, Comparative Example 2 (wherein the SiH / Vi ratio is 0.48) has a tackiness of 2×10 4 Provides a tacky surface with a relatively low storage modulus of less than Pa. Furthermore, Comparative Example 3 (SiH / Vi=1.25) does not show melting behavior due to higher crosslink density. Therefore, without wishing to be bound by theory, it is believed that the curable silicone composition provides a less tacky or non-tacky surface after thermal curing, as well as melting properties, when the SiH / Vi ratio is greater than 0.48 and less than 1.00.

[0127] Comparative Examples 4 and 5 demonstrate that curable silicone compositions with 3.1 and 3.8 mmol / 100 g methacryl content in the total composition exhibit melting behavior even after UV irradiation due to the absence of further crosslinking by UV radical reaction. In contrast, Examples 1 to 8 do not exhibit melting behavior after full curing (when methacryl content is 4 mmol / 100 g or more). It is therefore believed that the methacryl content confers UV crosslinking reaction and high temperature stability. Without wishing to be bound by theory, it is believed that the curable silicone composition provides a fully compatible network after UV curing after thermal curing when the methacryl content in the total mass of components (A) to (G) is 4 mmol / 100 g or more.

[0128] Comparative Examples 6 and 7 show that the curable silicone composition without component (B) did not provide hot melt behavior when the SiH / Vi ratio was 0.86 and produced a sticky surface (2×10 at 20° C.) when the SiH / Vi ratio was 0.41, respectively. 4 It is demonstrated that the composition provides a low storage modulus of less than 1 Pa. Therefore, without component (B), it was not possible to obtain a solventless curable composition that exhibits a non-tacky surface having hot melt properties after heat curing. [Industrial Applicability]

[0129] The active energy ray-curable silicone composition of the present invention has excellent handling properties at room temperature without using a solvent, is cured by heat to form a pre-cured product that is less sticky or non-sticky at room temperature and has excellent melt viscosity when heated, and is further cured by active energy rays to form a cured product that does not have hot melt properties. Therefore, the active energy ray-curable silicone composition is useful as a sealant, adhesive, or coating for optical semiconductor elements in electric / electronic devices.

Claims

1. An active energy ray-curable silicone composition, comprising: (A) an organopolysiloxane resin represented by the following average unit formula: (R １ ３ Yes １／２ ) ａ (R ２ R １ ２ Yes １／２ ) ｂ (Yes) ４／２ ) ｃ (HO １／２ ) ｄ In the formula, each R １ are independently an alkyl group; R ２ is an alkenyl group, and the subscripts a, b, c, and d are numbers that satisfy the conditions a≧0, b>0, 0.3≦c≦0.7, 0≦d≦0.05, and a+b+c=1; (B) the viscosity at 25°C is 1,000 mPa·s or less, １ ) an organosiloxane oligomer having at least one silicon-bonded alkenyl group and at least one silicon-bonded aryl group in the molecule; ２ ) an organosiloxane oligomer having at least one silicon-bonded hydrogen atom and at least one silicon-bonded aryl group in the molecule, and component (B １ ) and (B ２ and a mixture of said organosiloxane oligomers with (C) If necessary, １ ) having at least one alkenyl group in the molecule, and a silicon-bonded aryl group and SiO ４／２ Organopolysiloxane having no units, (C ２ ) an organopolysiloxane having at least one silicon-bonded hydrogen atom in the molecule and having no silicon-bonded aryl groups; ３ ) is a disilylbenzene represented by the following general formula: HR １ ２ Si-C ６ H ４ -SiR １ ２ H In the formula, each R １ are independently alkyl groups; and mixtures thereof; (D) an organosilicon compound having in the molecule at least one silicon-bonded acryloxyalkyl group or silicon-bonded methacryloxyalkyl group, and at least one silicon-bonded hydrogen atom; (E) a catalytic amount of a hydrosilylation reaction catalyst, An active energy ray-curable silicone composition in which, based on the total mass of components (A) to (C), the amount of component (A) is in the range of 50 to 80 mass%, the amount of component (B) is in the range of 5 to 40 mass%, and the amount of component (C) is in the range of 0 to 30 mass%, and the amount of component (D) is in the range of 2 to 20 parts by mass per 100 parts by mass of the total mass of components (A) to (C), with the proviso that the molar ratio of all silicon-bonded hydrogen atoms to all silicon-bonded alkenyl groups in components (A) to (D) is 0.5 or greater and less than 1.

0.

2. Ingredients (B １ ) is present, and is an organosiloxane oligomer represented by the following general formula: R ２ R ３ ２ SiO(R ３ ２ SiO) ｍ SiR ３ ２ R ２ In the formula, each R ２ are independently an alkenyl group, and each R ３ are independently an alkyl group or an aryl group, provided that at least one R ３ is an aryl group; and subscript m is an integer from 0 to 10.

3. Ingredients (B １ ) is expressed as follows: (CH ２ =CH)(CH ３ ) ２ SiO(C ６ H ５ ) ２ SiOSi(CH ３ ) ２ (CH=CH ２ )、 (CH ２ =CH)(CH ３ ) ２ SiO(C ６ H ５ )(CH ３ )SiO Si(CH ３ ) ２ (CH = CH ２ ), and (CH ２ =CH) (CH ３ ) (C ６ H ５ )SiOSi(CH ３ ) (C ６ H ５ ) (CH=CH ２ 3. The active energy ray-curable silicone composition according to claim 2, wherein the organosiloxane oligomer is at least one selected from the group consisting of organosiloxane oligomers represented by the formula:

4. Ingredients (B ２ ) is present, and is an organosiloxane oligomer represented by the following general formula: HR ３ ２ SiO(R ３ ２ SiO) ｍ SiR ３ ２ H In the formula, each R ３ are independently an alkyl group or an aryl group, provided that at least one R ３ is an aryl group; and subscript m is an integer from 0 to 10.

5. Ingredients (B ２ ) is expressed as follows: H (CH ３ ) ２ SiO(C ６ H ５ ) ２ SiOSi(CH ３ ) ２ H, and H (CH ３ ) ２ SiO(C ６ H ５ ) (CH ３ )SiOSi(CH ３ ) ２ 5. The active energy ray-curable silicone composition according to claim 4, wherein the organosiloxane oligomer is at least one selected from organosiloxane oligomers represented by H.

6. The acryloxyalkyl group or methacryloxyalkyl group of component (D) is represented by the following general formula: 【Chemistry 1】 In the formula, R ４ is a methyl group or a hydrogen atom, R ５ 2. The active energy ray-curable silicone composition according to claim 1, wherein is an alkylene group having 2 to 6 carbon atoms.

7. Component (D) is represented by the following general formula: 【Chemistry 2】 At least one organosilicon compound selected from the compounds represented by In the formula, each R ６ are independently an alkyl group or an aryl group, and X is a group represented by the following general formula: 【Chemistry 3】 In the formula, R ４ is a methyl group or a hydrogen atom, R ５ is an alkylene group having 2 to 6 carbon atoms, subscript n is an integer from 1 to 10, subscript n' is an integer from 1 to 10, and subscript n'' is an integer from 0 to 10.

8. 2. The active energy ray-curable silicone composition according to claim 1, wherein component (D) is used in an amount such that the content of the acryloxyalkyl group or the methacryloxyalkyl group is 4 mmol / 100 g or more, relative to the total mass of components (A) to (E).

9. 2. The active energy ray-curable silicone composition according to claim 1, further comprising (F) a hydrosilylation reaction inhibitor in an amount that adjusts the cure of the composition.

10. 10. The active energy ray-curable silicone composition according to claim 9, further comprising (G) a photoradical initiator in an amount sufficient to promote curing of the composition with active energy rays.

11. The active energy ray-curable silicone composition according to claim 10, wherein component (D) is used in an amount such that the content of the acryloxyalkyl group or the methacryloxyalkyl group is 4 mmol / 100 g or more, relative to the total mass of components (A) to (G).

12. 2. The active energy ray-curable silicone composition according to claim 1, further comprising (G) a photoradical initiator in an amount that promotes curing of the composition with active energy rays.

13. A pre-cured product obtained by subjecting the active energy ray-curable silicone composition according to any one of claims 1 to 12 to a hydrosilylation reaction.

14. A cured product obtained by exposing the pre-cured product according to claim 13 to active energy rays.

15. A method for producing a cured product, comprising the steps of: 1) curing the curable silicone composition according to any one of claims 1 to 12 to form a pre-cured product by a hydrosilylation reaction; 2) placing the pre-cured material on a target substrate and applying heat and / or pressure to the pre-cured material disposed on the target substrate; 3) exposing the pre-cured product to active energy rays.

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