Method for manufacturing heat- and light-curable silicon oxide compositions and their cured products

Abstract

A heat- and light-curable silicon oxide composition, containing (A) An organopolysiloxane having at least three (meth)acrylate groups in one molecule. (B) An organopolysiloxane having at least two alkenyl groups and no (meth)acrylate groups in one molecule. (C) An organohydrogen polysiloxane having at least two hydrogen silyl groups in one molecule. (D) Catalyst for hydrosilaneization reaction, and (E) Photopolymerization initiator, The ratio of the number of (meth)acrylic acid groups in component (A) to the number of alkenyl groups in the composition is 0.9 to 3.0. The ratio of hydrosilyl groups to alkenyl groups is 0.8~1.2. This thermo- and photocurable silicon oxide composition system allows for individual and convenient management of the first and second stages of curing.

Description

Technical Field

[0001] []

[0002] The present invention relates to thermally and photocurable silicon oxide compositions, and more specifically, to a method for manufacturing a two-stage curable liquid silicon oxide composition that is partially cured by a heated hydrosilaneization reaction in the presence of a hydrogenation silanization catalyst and a photopolymerization initiator, and is subsequently fully cured by free radical curing using ultraviolet light, and a cured product thereof. Prior Technology

[0003] Two-stage curing liquid silica materials are highly attractive due to their ability to distribute and manage manufacturing steps. For example, in the sealing layer of optical devices, the light extraction efficiency varies depending on the dispersion of phosphors, thus requiring strict management of dispersion. However, when using thermosetting materials in sealing materials, the viscosity of the base material decreases during thermosetting, making phosphor sedimentation easier, thus making it difficult to simultaneously manage dispersion and cure. Using a two-stage curing material in the sealing layer allows for the first curing stage to control phosphor dispersion, followed by a second curing stage to achieve the required hardness, enabling mounting onto semiconductor devices. Thus, in order to facilitate the simplification of difficult manufacturing processes and to develop novel manufacturing processes different from those to date, two-stage curing silicone materials have been proposed for wide applications such as adhesive films, optical device sealing materials, or temporary fixatives and adhesives for electronic components, and research and development are actively underway.

[0004] Patent document 1 reports that a liquid silica composition containing an alkenyl-containing organic polysiloxane, a platinum catalyst for hydrosilanization, and a high-energy ray-activated platinum catalyst is subjected to an addition reaction at room temperature and then subjected to a heating environment to undergo a single hardening process, resulting in a thermoplastic silica that is non-flowable at room temperature. Then, the thermoplastic silica is irradiated with high-energy rays and subjected to a heating environment at room temperature to undergo a hydrosilanization reaction, thereby obtaining a hardened silica curing material with high hardness.

[0005] Patent document 2 reports that a liquid silica adhesive composition containing an alkenyl-containing organic polysiloxane, a hydrosilylation reaction catalyst, and a thermal free radical reaction initiator is subjected to an environment from room temperature to 100°C, and a first-stage curing is carried out by an addition reaction to obtain a silica cured product. Then, the obtained silica cured product is subjected to a temperature environment of 150~190°C, which is higher than the first-stage curing temperature, and a second-stage curing is carried out by a thermal free radical reaction to obtain a silica cured product with high hardness.

[0006] Patent document 3 reports that a liquid silica adhesive composition containing an organopolysiloxane with condensation reactive groups, an alkenyl organopolysiloxane, a condensation reaction catalyst, and a thermal free radical reaction initiator is subjected to a condensation reaction in the presence of moisture to carry out the first stage of curing, thereby obtaining a silica cured product. The obtained silica cured product is then subjected to a heating environment to carry out the second stage of curing through thermal free radical reaction, thereby obtaining a silica cured product with high hardness.

[0007] Incidentally, the methods described in Patent Documents 1 and 2 both employ a heating-based curing mechanism in both the first and second stages of curing. It is generally difficult to manage the intermediate state during thermo-curing; therefore, in order to reproducibly obtain the cured state of the silicon oxide compound obtained from the first curing stage, strict temperature distribution management is necessary. The methods in Patent Documents 1 and 2 are difficult to apply in practice. On the other hand, the method described in Patent Document 3, after performing the first hardening by condensation reaction that generally produces more gas-releasing components, is followed by heating and free radical hardening. Therefore, it may produce defects such as cracks due to reversal or volatilization of gas-releasing components. [Previous Technical Documents] [Patent Document]

[0008] [Patent Document 1] International Publication No. 2019 / 088066 [Patent Document 2] Japanese Patent Application Publication No. 2007-191629 [Patent Document 3] International Publication No. 2018 / 186165 Summary of the Invention

[0009] [The problem the invention aims to solve]

[0010] The present invention was made in view of the above circumstances, and its object is to provide a two-stage curing type silicon oxide composition in which the first stage of curing and the second stage of curing can be individually and easily managed. [Methods used to solve the problem]

[0011] As a result of active research by the inventors to solve the above-mentioned problems, they discovered that a composition containing (meth)acrylic acid-based organopolysiloxanes, alkenyl-based organopolysiloxanes, and organohydrogen-based polysiloxanes in a specific ratio can individually and easily manage the first stage of curing using heat and the second stage of curing using light in the presence of a hydrosilanization reaction catalyst and a photopolymerization initiator, thus completing the present invention.

[0012] That is, the present invention provides 1. A heat- and light-curable silicon oxide composition, comprising... (A) An organopolysiloxane having at least three (meth)acrylate groups in one molecule. (B) An organopolysiloxane having at least two alkenyl groups and no (meth)acrylate groups in one molecule. (C) Organohydrogen polysiloxanes having at least two hydrogen silyl groups in one molecule. (D) Catalyst for hydrosilanization reaction, and (E) Photopolymerization initiator, The ratio of the number of (meth)acrylic acid groups in component (A) to the number of alkenyl groups in the composition is 0.9 to 3.0. The ratio of the number of hydrosilyl groups to the number of alkenyl groups is 0.8 to 1.2. 2. A heat- and light-curable silicon oxide composition as described in 1, wherein the aforementioned component (A) is (Ai), (A-ii), or both thereof described below. (Ai) an organic polysiloxane represented by the following formula (1), (In the formula, R1 independently represents alkyl with 1 to 20 carbon atoms or aryl with 6 to 20 carbon atoms, substituted or unsubstituted; R2 independently represents alkyl with 1 to 20 carbon atoms or oxygen atom; R3 independently represents alkyl, methacrylate, alkyl, alkoxy, or methacrylate alkoxy; k represents an integer from 0 to 1,000; m represents an integer from 0 to 20; a and b independently represent integers from 0 to 3, and a+b+m is an integer greater than 3; the order of the siloxane units in parentheses marked with k and m is arbitrary.) (A-ii) Organic polysiloxanes with a number-average molecular weight (Mn) of 3,000 to 100,000, as expressed by formula (2) below. (In the formula, R1 represents the same as above, A represents the siloxane unit expressed by the following formula (3), and p, q, and r are numbers where p>0, q>0, r>0 and satisfy p+q+r=1) (In the formula, R1, R2 and R3 are synonyms of the above, n represents an integer from 0 to 10, and c represents an integer from 1 to 3). 3. A heat- and light-curable silicon oxide composition as described in 1, wherein the aforementioned component (B) is (B-iii), (B-iv), or both thereof described below. (B-iii) A linear organopolysiloxane with a viscosity of 50~10,000,000 mPa·s at 23°C, expressed by the following formula (4). (In the formula, R1 represents the same as above, R4 represents an alkenyl group with 2 to 20 carbon atoms, and s represents an integer from 1 to 10,000) (B-iv) Organic polysiloxanes represented by the following formula (5) (In the formula, R1 and R4 represent the same as above, and t, u, and v are numbers that are t>0, u>0, v>0 and satisfy (t+u+v)=1). 4. A heat- and light-curable silicone composition as described in 1, wherein the aforementioned component (C) is a linear organohydrogen polysiloxane represented by the following formula (7). (In the formula, R1 represents the same as above, f represents 1 or 2, w represents an integer that satisfies 0≦w≦2, and x and y represent positive integers that satisfy 2≦x+y≦800 and 0.6≦x / (x+y+2)≦1.0). 5. A thermo- and photocurable silicon oxide composition as described in 1, wherein the aforementioned component (E) is a photoradical polymerization initiator that does not contain nitrogen, sulfur, or phosphorus atoms. 6. A method for manufacturing a hardened material, comprising: (α) The step of heating the heat- and light-curing silicon oxide composition as described in any of 1 to 5 to partially cure the composition and make it into a semi-cured composition. (β) The step of irradiating the resulting semi-hardened composition with ultraviolet light to harden it completely. [Invention Effects]

[0013] The thermally and photocurable silicon oxide compositions of this invention are easy to control and process because the methods for inducing curing in the two-stage curing steps are different. That is, the first-stage curing using light is carried out instantaneously during the polymerization reaction under ultraviolet irradiation, so it can be carried out at room temperature and in a short time. Furthermore, since the semi-cured composition after the first curing is easy to process and does not change in hardness even after long periods of low-temperature environments such as refrigeration, sufficient time can be ensured before the second-stage curing using heat. The heat- and light-curing silicon oxide composition of the present invention, which has these properties, is particularly suitable for adhesive films, sealing materials for optical devices, or adhesives for components of electronic machines. Implementation

[0014] The present invention will now be described in detail. The thermally and photocurable silicon oxide composition of the present invention includes the following components (A) to (E).

[0015] [1] (A)Ingredients In the heat- and light-curable silica composition of the present invention, component (A) is an organopolysiloxane having at least three (meth)acrylate groups per molecule, preferably of the following formulas (Ai), (Aii), or both. Furthermore, in the present invention, the term (meth)acrylate group refers to an acrylic group or a methacrylate group.

[0016] (Ai) an organic polysiloxane represented by the following formula (1),

[0017] (In the formula, R1 independently represents alkyl with 1 to 20 carbon atoms or aryl with 6 to 20 carbon atoms, substituted or unsubstituted; R2 independently represents alkyl with 1 to 20 carbon atoms or oxygen atom; R3 independently represents alkyl, methacrylate, alkyl, alkoxy, or methacrylate alkoxy; k represents an integer from 0 to 1,000; m represents an integer from 0 to 20; a and b independently represent integers from 0 to 3, and a+b+m is an integer greater than 3; the order of the siloxane units in parentheses marked with k and m is arbitrary).

[0018] (A-ii) Organic polysiloxanes with a number-average molecular weight (Mn) of 3,000 to 100,000, as expressed by formula (2) below. (In the formula, R1 represents the same as above, A represents the siloxane unit expressed by the following formula (3), and p, q, and r are numbers that are p>0, q>0, r>0 and satisfy p+q+r=1).

[0019] (In the formula, R1, R2 and R3 are synonyms of the above, n represents an integer from 0 to 10, and c represents an integer from 1 to 3).

[0020] The alkyl group having 1 to 20 carbon atoms as R1, preferably having 1 to 10 carbon atoms, can be straight-chain, branched, or cyclic. Specific examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tributyl, n-hexyl, cyclohexyl, n-octyl, 2-ethylhexyl, n-decyl, etc. Furthermore, specific examples of aryl groups with 6 to 20 carbon atoms, preferably 6 to 10 carbon atoms, include phenyl, tolyl, xylyl, and naphthyl. Furthermore, some or all of the hydrogen atoms bonded to the carbon atoms may be replaced by other substituents, such as halogen-substituted hydrocarbon groups like chloromethyl, bromoethyl, trifluoropropyl, and cyanoethyl, and cyano-substituted hydrocarbon groups. In these, alkyl or phenyl groups having 1 to 5 carbon atoms are preferred as R1, and methyl, ethyl, or phenyl groups are even more preferred.

[0021] The alkyl group of R2 with 1 to 20 carbon atoms can be straight-chain, branched, or cyclic. Specific examples include methylene, ethyl, propyl, trimethylene, tetramethylene, isobutyl, pentamethylene, hexamethylene, heptamethylene, octamethylene, and nonamethylene. In these, R2 is preferably an oxygen atom, methylene, ethylene, or trimethylene, and more preferably an oxygen atom or ethylene.

[0022] Specific examples of R3 are shown in the following formulas, but are not limited to these.

[0023] (In the formula, g represents an integer from 1 to 4).

[0024] In the above formula (1), a and b are integers from 0 to 3, and the sum of a and b (a+b+m) is 3 or more. When a+b+m is less than 3, it is difficult for the photo-curing reaction to occur, and there is a possibility that the hardness of the resulting silicon oxide cured material is insufficient. Ideally, a and b are 2, and m is 4. k is an integer from 0 to 1,000. When k exceeds 1,000, poor polymerizability may occur. Based on the viewpoint of the non-volatility and polymerizability of the (Ai) component, k is preferably an integer from 30 to 500, and more preferably an integer from 50 to 400. m is an integer from 0 to 20, preferably an integer from 0 to 10, and even more preferably 0. If m exceeds 20, the composition may produce turbidity during hardening.

[0025] In the above formula (2), p, q, and r are numbers where p>0, q>0, and r>0 respectively and satisfy p+q+r=1. Based on the treatment of the constituents and the hardness of the obtained silicon oxide hardened material, p is preferably 0.05~0.07, q is preferably 0.33~0.35, and r is preferably 0.58~0.62.

[0026] The number-average molecular weight of component (A-ii) is in the range of 3,000 to 100,000, preferably in the range of 5,000 to 10,000. When the number-average molecular weight is below 3,000, the number of (meth)acrylic acid groups per molecule may be less than 3, and there is a risk that the hardness of the silicone-cured product obtained after two-stage curing may be insufficient. When the number-average molecular weight exceeds 100,000, there is a risk that the compatibility of component (A-ii) may decrease. Furthermore, the number average molecular weight of this invention is a standard polystyrene conversion value determined by gel permeation chromatography (GPC) using tetrahydrofuran (THF) as the developing solvent.

[0027] (A) One ingredient may be used alone or in combination of two or more. Furthermore, since component (A-ii) sometimes becomes solid in the environment of use, it can also be used in advance dissolved in component (Ai) or liquid organic compounds containing (meth)acrylic acid groups. From a processability point of view, the viscosity of component (A) at 23°C is preferably below 100,000 mPa·s (typically 1 to 100,000 mPa·s), and more preferably below 10,000 mPa·s (e.g., 5 to 10,000 mPa·s). Furthermore, the viscosity of this invention is measured using a type B rotational viscometer.

[0028] [2] (B) Components In the heat- and light-curable silicone composition of the present invention, component (B) is an organopolysiloxane having at least two alkenyl groups in one molecule and no (meth)acrylate groups, preferably (B-iii), (B-iv), or both thereof described below.

[0029] (B-iii) A linear organopolysiloxane with a viscosity of 50~10,000,000 mPa·s at 23°C, expressed by the following formula (4). (In the formula, R1 represents the same as above, R4 represents an alkenyl group with 2 to 20 carbon atoms, and s represents an integer from 1 to 10,000). (B-iv) Organic polysiloxanes represented by the following formula (5) (In the formula, R1 and R4 represent the same as above, and t, u, and v are numbers that are t>0, u>0, v>0 and satisfy (t+u+v)=1).

[0030] In the above formula (4), R1 is exemplified by the same as that in formula (1), but preferably methyl or phenyl. The alkenyl group of R4, which has 2 to 20 carbon atoms, can be linear, branched, or cyclic. Examples of such alkenyl groups include vinyl, allyl, butenyl, pentenyl, hexenyl, and octenyl, with vinyl being the most preferred. s is an integer from 1 to 10,000, preferably an integer from 100 to 1,000.

[0031] The viscosity of component (B-iii) at 25°C is 50~10,000,000 mPa·s, preferably 100~100,000 mPa·s.

[0032] In the above formula (5), R1 is exemplified by the same as that in formula (1), but preferably methyl or phenyl. The alkenyl group of R4, which has 2 to 20 carbon atoms, can be linear, branched, or cyclic. Examples of such alkenyl groups include vinyl, allyl, butenyl, pentenyl, hexenyl, and octenyl, with vinyl being the most preferred. t, u, and v are numbers where t>0, u>0, and v>0 respectively and (t+u+v)=1. Based on the viewpoint of hardening properties and the hardness of hardened materials, (t+u) / v is preferably 0.3~2.0, and more preferably 0.5~1.0.

[0033] The number-average molecular weight of (B-iv) components is preferably 500 to 500,000, more preferably 1,000 to 100,000. When the number-average molecular weight is below 500, there is a possibility that the number of alkenyl groups in one molecule is less than 2, which may result in insufficient hardness of the silicon oxide cured product obtained after two-stage curing. When the number-average molecular weight exceeds 500,000, there is a risk of reduced compatibility of (B-iv) components.

[0034] (B) Components may be used alone or in combination of two or more. Furthermore, since component (B-iv) may become solid in the environment in which it is used, it can also be dissolved in component (B-iii) before use. From a processability point of view, the viscosity of component (B) at 23°C is preferably below 100,000 mPa·s (typically 1 to 100,000 mPa·s), and more preferably below 10,000 mPa·s (e.g., 5 to 10,000 mPa·s).

[0035] (B) The ratio of the number of (meth)acrylic acid groups in component (A) to the number of alkenyl groups in the composition is 0.9 to 3.0. If this ratio is less than 0.9, there is a possibility that the curing in the second stage will be insufficient; if it exceeds 3.0, the amount of alkenyl groups will be too small, and there is a possibility that the curing in the first stage will be insufficient.

[0036] [3] (C) Components Component (C) is an organohydrosiloxane having at least two hydroxysilyl groups in one molecule, specifically exemplified by the average composition formula (6) below. (In the formula, R1 represents the same as above, d is 0.7~2.1, e is 0.001~1.0, and represents a number that satisfies 0.8≦d+e≦3.0).

[0037] In the above formula (6), d is preferably 1.0~1.8, e is preferably 0.1~1, d+e is preferably 1≦d+e≦2.4, and more preferably 1.6≦d+e≦2.2. If it is within this range, foaming during hardening can be suppressed, the hardness of the hardened material can be improved, and it is not easy to cause hardness changes over time.

[0038] In particular, as component (C), it is preferably a linear organohydrogen polysiloxane represented by the following formula (7). In formula (7), R1 is exemplified as having the same meaning as above, but preferably is methyl. f represents 1 or 2, with 2 being preferred. w represents an integer that satisfies 0 ≦ w ≦ 2, preferably 0 or 2, and even more preferably 2. x and y represent positive integers that satisfy 2≦x+y≦800 and 0.6≦x / (x+y+2)≦1.0, more preferably positive integers that satisfy 7≦x+y≦700 and 0.7≦x / (x+y+2)≦0.9.

[0039] (C) The kinematic viscosity of component C at 23°C is preferably 0.5~200 mm² / s, more preferably 1~50 mm² / s. Here, the kinematic viscosity is the value measured using a Cannon-Fenske viscometer.

[0040] (C) Components can be used alone or in combination of two or more. (C) The amount of the component is such that the ratio of the number of silyl groups to the number of alkenyl groups in the composition is in the range of 0.8 to 1.2, preferably in the range of 0.9 to 1.1. If it is less than 0.8, there may be insufficient hardening properties in the first stage of hardening and insufficient hardness of the resulting hardened product. If it exceeds 1.2, there is a possibility that the hardness will be too high due to the first stage of hardening, and the advantages of the second stage of hardening will be lost.

[0041] [4] (D) component Component (D) is a hydrosilanization catalyst used to promote the addition reaction of alkenyl groups in components (A) and (B) with Si-H groups in component (C). Specific examples include carbon powder containing platinum metal, platinum black, platinum chloride, platinum chloride acid, reaction products of platinum chloride acid and monohydric alcohols, complexes of platinum with vinylsiloxanes such as divinyltetramethyldisiloxane, complexes of platinum chloride acid and alkenes, platinum group metal catalysts such as platinum diacetate platinum, palladium catalysts, and rhodium catalysts, etc. However, from the viewpoint of reactivity, those containing platinum are preferred, and more preferably complexes of platinum with vinylsiloxanes.

[0042] The amount of component (D) is not limited as long as it can promote the hydrosilanization reaction. However, relative to the total of components (A), (B) and (C), the amount of component (D) in terms of metal mass is preferably in the range of 0.01 to 500 ppm, more preferably in the range of 0.05 to 100 ppm, and even more preferably in the range of 0.01 to 50 ppm.

[0043] [5] (E) Components Component (E) is a photopolymerization initiator that generates organic free radical species by absorbing ultraviolet light and initiates the polymerization reaction of (meth)acrylic acid groups. In order not to hinder the addition reaction of the first-stage hardening mechanism, the photopolymerization initiator of component (E) preferably does not contain nitrogen, sulfur, or phosphorus atoms. Specific examples of such photopolymerization initiators include 2,2-diethoxyacetophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one (Omnirad 651 manufactured by IGM Resins BV), 1-hydroxy-cyclohexyl-phenyl-one (Omnirad 184 manufactured by IGM Resins BV), 2-hydroxy-2-methyl-1-phenyl-propane-1-one (Omnirad 1173 manufactured by IGM Resins BV), 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propane-1-one)-benzyl]-phenyl}-2-methyl-propane-1-one (Omnirad 127 manufactured by IGM Resins BV), and methyl phenylglyoxylate (Omnirad MBF manufactured by IGM Resins BV). Of these, based on the viewpoint of compatibility with components (A) and (B), 2,2-diethoxyacetophenone and 2-hydroxy-2-methyl-1-phenylpropane-1-one (IGM Resins BV (stock) Omnirad 1173) are preferred.

[0044] (E) Components can be used alone or in combination of two or more. The amount of component (E) added is preferably in the range of 0.01 to 20% by mass relative to the total mass of components (A), (B), and (C). Within this range, the hardening properties are good, and the deep hardening properties are excellent.

[0045] [6] Other ingredients In addition to the components (A) to (E) mentioned above, the thermal and photocurable silicon oxide composition of the present invention may also contain other components without compromising the purpose of the present invention. Examples of other components include, for instance, reaction control agents such as 3-methyl-1-butyn-3-ol and ethynylmethyldecylmethanol that control the reactivity of platinum catalysts; adhesive aids having adhesion-improving groups such as carbonyl, epoxy, and alkoxysilyl groups; thixotropic control agents such as fuming silica; reinforcing agents such as crystalline silica; antioxidants; light stabilizers; heat-resistant enhancers such as metal oxides and metal hydroxides; thermally conductive fillers such as titanium dioxide and pigments; dyes; and alumina; viscosity modifiers such as non-reactive silicone oils without reactive functional groups; and electrical conductivity improvers such as silver and gold powders.

[0046] The heat- and light-curing silicon oxide composition of the present invention can be prepared by mixing the above-mentioned components (A) to (E) and other components used as needed using conventional methods. At this time, the components of the present invention can be prepared as a single liquid, or as two liquids, or divided into three parts for separate preparation, and mixed in any proportion when used.

[0047] The method for manufacturing cured products of thermo- and photo-curable silicon oxide compositions of the present invention includes... (α) The step of heating a heat- and light-curable silicon oxide composition to partially cure it into a semi-cured composition, and (β) The step of irradiating the resulting semi-hardened composition with ultraviolet light to harden it completely.

[0048] The heating conditions in step (α) are preferably 50~150℃, more preferably 80~120℃ for 10 minutes to 1 day, and even more preferably 30 minutes to 1 hour. The ultraviolet light used in step (β) is preferably in the range of 200-500 nm, more preferably 200-350 nm. From the viewpoint of preventing discoloration, the irradiation temperature is preferably 20-40°C, the irradiation intensity is more preferably 30-2,000 mW / cm², and the irradiation dose is preferably 150-100,000 mJ / cm². As a light source for ultraviolet light, 365nm UV-LED lamps, metal halide lamps, high-pressure mercury lamps, etc., can be used. An example of an ultraviolet irradiation method is to irradiate the constituent material with an appropriate amount of ultraviolet light. However, when irradiating transparent substrates such as glass or resin films, ultraviolet light can also be irradiated through the glass or film. During ultraviolet irradiation, to suppress the curing hindrance caused by oxygen, it is preferable to use a nitrogen or argon atmosphere. [Example]

[0049] The present invention will be described in more detail below with examples and comparative examples, but the present invention is not limited to these examples. Furthermore, the viscosity at 23°C was measured using a type B rotational viscometer, and the kinematic viscosity at 23°C was measured using a Cannon-Fenske viscometer. Also, Vi represents vinyl, and Me represents methyl.

[0050] [1] Modulation of thermo- and photocurable silicon oxide compositions [Examples 1-1 to 1-6, Comparative Examples 1-1 to 1-5] Mix the components (A) to (E) shown below and other components in the proportions (parts by mass) shown in Tables 1 and 2 to prepare a heat- and light-curable silicon oxide composition.

[0051] (A)Ingredients (Ai-1): an organopolysiloxane represented by the following formula (8) (viscosity at 23°C 3,000 mPa·s, acrylic acid content 0.02 moles / 100g) (In the formula, the arrangement of each siloxane unit indicated in parentheses is random or block).

[0052] (A-ii-1): An organopolysiloxane (number average molecular weight 5,700, average number of methacrylate groups per molecule 3.7, methacrylate group content 0.0656 moles / 100g, vinyl content 0.0164 moles / 100g) with a molar ratio of siloxane units / (ViMe 2SiO 1 / 2 units) / (Me 3SiO 1 / 2 units) as expressed by the following formula (9):

[0053] (A-ii-2): An organopolysiloxane (number average molecular weight 5,400, average number of methacrylate groups per molecule 4.3, methacrylate group content 0.0794 moles / 100g, vinyl content 0.0596 moles / 100g) with a molar ratio of siloxane unit / (ViMe 2SiO 1 / 2 unit) / (Me 3SiO 1 / 2 unit) / (SiO 2 unit) as expressed in the above formula (9) of 0.072 / 0.054 / 0.334 / 0.540.

[0054] (B) Ingredients (B-iii-1): an organopolysiloxane represented by the following formula (10) (viscosity at 23°C 3,000 mPa·s, vinyl content 0.01 moles / 100g) (In the formula, the arrangement of each siloxane unit marked in parentheses is random or block)

[0055] (B-IV-1): an organopolysiloxane represented by the following average formula (11) (number average molecular weight 4,500, average number of vinyl groups per molecule 3.7, vinyl content 0.082 moles / 100g)

[0056] (C) Ingredients (C-1): an organohydrogen polysiloxane represented by the following formula (12) (with a kinematic viscosity of 44.7 mm² / s at 23°C and a hydrogen atom content of silicon atom bonds = 0.0113 moles / g).

[0057] (In the formula, the arrangement of each siloxane unit marked in parentheses is random or block)

[0058] (D) Ingredients (D-1) Toluene solution of platinum 1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (platinum content 0.5% by mass)

[0059] (E) Components (E-1): 2-Hydroxy-2-methyl-1-phenyl-propane-1-one (IGM Resins BV (stock) Omnirad 1173)

[0060] (Other ingredients) Reaction control agent: ethynylmethyldecylmethanol Diluent: a disiloxane compound represented by the following structural formula (13).

[0061]

[0062]

[0063] [2] Manufacturing of cured products of thermo- and photo-curable silicon oxide compositions [Examples 2-1 to 2-6, Comparative Examples 2-1 to 2-6] The heat- and light-curing silicon oxide compositions obtained in Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-5 were allowed to stand at 120°C for 1 hour to perform the first stage of curing. After cooling the resulting cured products to 25°C, the penetration or Shore A hardness of the cured products was measured using a penetration gauge (1 / 4 cone) or a Shore A hardness tester manufactured by Lihe Co., Ltd., based on JIS K 6249. When the penetration was less than 1 and could not be measured, the Shore A hardness was used. Subsequently, the cured material obtained from the first stage of hardening was irradiated with ultraviolet light at 25°C using a UV-LED lamp with a wavelength of 365 nm under a nitrogen atmosphere, with an irradiation intensity of 100 mW / cm² and an irradiation dose of 3,000 mJ / cm². The hardness of the material was then measured in the same manner as that of the material from the first stage. The results are shown in Tables 3 and 4.

[0064]

[0065]

[0066] As shown in Tables 3 and 4, it can be seen that the thermal and photocurable silicon oxide compositions prepared in Examples 1-1 to 1-6 have a large difference in hardness between the first stage of curing using heat and the second stage of curing using light. On the other hand, when the compositions of Comparative Examples 1-1 and 1-3, in which the ratio of (meth)acrylic groups in component (A) to the number of alkenes in the composition exceeds 3.0, do not cause the first stage of curing by heat. When the compositions of Comparative Examples 1-2, 1-4 and 1-5, in which the ratio of (meth)acrylic groups in component (A) to the number of alkenes in the composition is the same, the first stage of curing by heat is excessive, and there is almost no difference in hardness between the first and second stage of curing. It can be seen that they cannot be used as two-stage curing materials.

Claims

1. A thermo- and photocurable silica composition comprising (A) an organopolysiloxane having at least 3 (meth)acrylate groups in one molecule, (B) an organopolysiloxane having at least 2 alkenyl groups and no (meth)acrylate groups in one molecule, (C) an organohydrosilane having at least 2 hydrosilyl groups in one molecule, (D) a hydrosilylation reaction catalyst, and (E) a photopolymerization initiator, wherein the ratio of the number of (meth)acrylate groups in component (A) to the number of alkenyl groups in the composition is 0.9 to 3.0, and the ratio of the number of hydrosilyl groups to the number of alkenyl groups is 0.8 to 1.

2.

2. The heat- and light-curable silica composition as claimed in claim 1, wherein the aforementioned component (A) is (Ai), (A-ii) or both thereof, where (Ai) is an organopolysiloxane represented by the following formula (1), (where R1 independently represents substituted or unsubstituted alkyl with 1 to 20 carbon atoms or substituted or unsubstituted aryl with 6 to 20 carbon atoms, R2 independently represents oxygen atoms or alkyl with 1 to 20 carbon atoms, R3 independently represents acryloxyalkyl, methacryloxyalkyl, acryloxyalkoxy or methacryloxyalkoxy, k represents an integer from 0 to 1,000, m represents an integer from 0 to 20, a and b independently represent integers from 0 to 3, and a+b+m is an integer greater than 3, and the order of the silica units in parentheses marked with k and m is arbitrary) (A-ii) An organopolysiloxane with a number average molecular weight (Mn) of 3,000 to 100,000, as expressed in the following formula (2), (where R1 is synonymous with the above, A is a siloxane unit as expressed in the following formula (3), and p, q, and r are each p>0, q>0, r>0 and satisfying p+q+r=1) (where R1, R2 and R3 are synonymous with the above, n is an integer from 0 to 10, and c is an integer from 1 to 3).

3. The heat- and light-curable silica composition as claimed in claim 1, wherein the aforementioned component (B) is (B-iii), (B-iv) or both of the following, (B-iii) is a linear organopolysiloxane with a viscosity of 50 to 10,000,000 mPa·s at 23°C, expressed in the following formula (4), (where R1 represents the same as above, R4 represents an alkenyl group with 2 to 20 carbon atoms, and s represents an integer from 1 to 10,000) (B-iv) is an organopolysiloxane expressed in the following formula (5), (where R1 and R4 represent the same as above, and t, u, and v are each t>0, u>0, v>0 and satisfy (t+u+v)=1).

4. The heat- and light-curing silicone composition of claim 1, wherein the aforementioned component (C) is a linear organohydrogen polysiloxane represented by the following formula (7), (where R1 represents the same as above, f represents 1 or 2, w represents an integer satisfying 0 ≦ w ≦ 2, and x and y represent positive integers satisfying 2 ≦ x + y ≦ 800 and 0.6 ≦ x / (x + y + 2) ≦ 1.0).

5. The thermo- and photocurable silicon oxide composition as claimed in claim 1, wherein the aforementioned component (E) is a photoradical polymerization initiator that does not contain nitrogen, sulfur and phosphorus atoms.

6. A method for manufacturing a cured material, comprising (α) heating a heat- and light-curing silicon oxide composition as claimed in any one of claims 1 to 5 to partially cure the composition to obtain a semi-cured composition, and (β) irradiating the obtained semi-cured composition with ultraviolet light to completely cure it.