TWI887391B - Curable hot-melt polysilicone composition, its cured product, and laminate containing the composition or cured product - Google Patents

Abstract

[Problem] The present invention provides a hot-melt curable polysilicone composition, and a sheet or film formed therefrom. The hot-melt curable polysilicone composition can be cured at a low temperature below 100°C, has excellent storage stability, and forms a relatively hard and low-surface-sticky cured product by curing. [Solution] The curable hot-melt polysilicone composition of the present invention contains the following components and has hot-melt properties as a whole: (A) a solid organic polysiloxane resin containing components (A1) and (A2) in a mass ratio of 0:100 to 90:10, (A1) an organic polysiloxane having a curing-reactive functional group and containing 20 mol% or more of Q units; Resin, (A2) an organic polysiloxane resin having no curing-reactive functional groups and containing more than 20 mol% of Q units; (B) 10 to 100 parts by weight of a liquid or plastic linear or branched organic polysiloxane having a curing-reactive functional group; (C) an organic hydrogenated polysiloxane; and (D) a photoactive silane hydrogenation catalyst.

Description

Curable hot-melt polysilicone composition, its cured product, and laminate containing the composition or cured product

The present invention relates to a hot-melt curable polysilicone composition, a curable polysilicone sheet or film with a thickness of 10 to 1000 µm formed by the composition, a cured product thereof, and a laminate containing the composition or the cured product. The hot-melt curable polysilicone composition can be cured at a low temperature below 100°C, has excellent storage stability, and forms a relatively hard cured product with low surface viscosity by curing. The curable polysilicone sheet or film preferably does not contain voids and is substantially flat. In addition, the present invention relates to a use of the aforementioned composition or cured product (especially including semiconductor components such as semiconductor device components and optical semiconductor device components, and semiconductor devices having the cured product), and the aforementioned composition, a sheet or film formed therefrom, and a method for producing a laminate using the same.

Curable polysilicone compositions can be cured to form a cured product with excellent heat resistance, cold resistance, electrical insulation, weather resistance, water repellency and transparency, and are therefore used in a wide range of industries. Cured products of such curable polysilicone compositions are generally less likely to change color than other organic materials, and their physical properties deteriorate less over time, so they are also suitable as sealants for optical materials and semiconductor devices.

The applicant proposed a hot-melt curable granular polysilicone composition and a reactive polysilicone composition for molding in Patent Documents 1 and 2. These polysilicone compositions include so-called phenyl polysilicone resins, which have the advantages of excellent hot-melt properties and excellent hardness and strength of the cured product compared to methyl polysilicone resins.

On the other hand, in recent years, the miniaturization and high power of optical semiconductor devices have been continuously developed. When the above-mentioned hot-melt curable granular polysilicone compositions are applied, coloring from phenyl polysilicone resins may occur, especially at high temperatures above 200°C, and light reflectivity may decrease, especially in the field of reflective materials. Therefore, there is a strong demand for polysilicone compositions that achieve hot-melt properties and better mechanical strength of the cured product after molding, and meet higher requirements for heat resistance and coloring resistance.

Here, Patent Document 3 discloses a transparent hot-melt curable silicone sheet using methyl polysilicone resin. However, this composition is a mixture of all components and is difficult to ensure storage stability. Therefore, there is a problem that it cannot be cured quickly at low temperatures and a high temperature of more than 150°C is required for curing. Moreover, this curable silicone sheet also has a problem that it is difficult to produce a film with a thickness of more than 100 µm due to the production method disclosed. Prior Art Documents Patent Documents

Patent document 1: International Publication No. 2016/136243 Patent document 2: Japanese Patent Publication No. 2014-009322 Patent document 3: Japanese Patent Publication No. 2017-512224

Invention Problem to be solved

The purpose of the present invention is to provide a hot-melt curable polysilicone composition that can be cured at low temperature and has excellent preservation stability, and a relatively hardened material with low surface viscosity obtained by curing it. In addition, the present invention provides a sheet or film formed by the curable polysilicone composition, especially a sheet or film with a film thickness of 10 to 1000 µm that does not contain voids and is substantially flat, and a peelable laminate containing the sheet or film formed by the curable polysilicone composition. Moreover, a further purpose of the present invention is to provide a semiconductor device component containing a cured material of the curable polysilicone composition, a semiconductor device having the cured material, and a molding method for the cured material. Technical means for solving the problem

The inventors of the present invention have found through diligent research that the above-mentioned problem can be solved by using the following curable polysilicone composition, thereby completing the present invention. The curable polysilicone composition is characterized in that it contains the following components and the composition as a whole has hot melt properties, namely, it contains: an organic polysiloxane resin containing a functional group with curing reactivity and a non-hardening functional group in a specific ratio (20:80 to 90:10). An organic polysiloxane resin having a functional group with curing reactivity and being solid at 25°C; a linear or branched organic polysiloxane having at least two curing-reactive functional groups in the molecule and being liquid or plastic at 25°C; an organic hydrogenated polysiloxane; and a catalyst for silanization reaction that is active in the composition by irradiation with high energy rays. This composition has excellent low-temperature curing characteristics and storage stability by using a catalyst for silanization reaction that is active in the composition by irradiation with high-energy rays, and has good workability and can form a relatively hard cured product with low surface viscosity by using a specific combination of organic polysiloxane resin that is solid at 25°C and organic polysiloxane that is liquid or plastic at 25°C. The composition may further contain a substantially non-volatile silanization reaction curing retarder. In addition, since the organopolysiloxane resin in the composition that is solid at 25° C. suppresses the surface viscosity of the cured product of the composition and provides a relatively hard cured product, it is more preferred that the mass reduction rate of the organopolysiloxane resin when exposed to 200° C. for 1 hour is 2.0 mass % or less.

In addition, in the present invention, atmospheric pressure refers to the atmospheric pressure in the environment where the curable polysilicone composition of the present invention is processed in a laboratory or factory, etc., and is not limited to a specific pressure, but generally refers to a pressure in the range of from atmospheric pressure (1013.25 hPa) to plus or minus 100 hPa, and particularly refers to atmospheric pressure (1013.25 hPa).

In addition, in this specification, room temperature refers to the temperature of the environment in which the person who processes the curable polysilicone composition of the present invention is located. Room temperature usually refers to 0°C to 40°C, especially 15°C to 30°C, and especially 18°C to 25°C.

In addition, the present invention relates to a sheet or film formed from the above-mentioned curable polysilicone composition, wherein the sheet or film is characterized in that the components constituting the curable polysilicone composition are melt-kneaded in a temperature range of 50°C to 150°C and under vacuum or reduced pressure, and then formed into a sheet or film. Here, "sheet" generally refers to a thickness of 250 µm or more, and "film" refers to a thickness of less than 250 µm. However, for the sake of simplicity, this manual sometimes combines films and sheets and simply refers to them as "sheets". Effect of the invention

The curable polysilicone composition of the present invention has hot melt properties, can be cured at low temperatures by irradiation with high energy rays such as ultraviolet rays, and has excellent storage stability, and excellent handling workability (including control of curing reaction) and curing characteristics in overmolding. Moreover, the curable polysilicone composition has high thixotropy at temperatures exceeding 100°C, and no dripping will occur even if the substrate is heat-pressed and heat-cured using an oven or the like. In addition, the curable polysilicone composition of the present invention forms a relatively hard hardened material with low surface viscosity, so it can be suitably used as a sealant for protecting substrates. Moreover, it can also be used for double-sided bonding purposes that require a relatively hard bonding layer. The curable polysilicone composition of the present invention can be manufactured by a simple mixing step, and thus can be manufactured efficiently. In addition, the present invention can provide such a curable polysilicone composition in the form of a sheet or film having a thickness of 10 to 1000 µm without voids, or in the form of a peelable laminate containing the curable polysilicone composition sheet or film and a peelable sheet or film. In addition, the sheet or film formed by the curable polysilicone composition of the present invention, or the peelable laminate containing the same, can be cut into a desired size as needed and used in the manufacturing process of electronic parts, such as semiconductor devices, and can be applied to industrial production processes such as one-time sealing or one-time bonding of large-area substrates.

The following is a detailed description of the implementation of the present invention. The present invention is not limited to the following implementation, and can be implemented in various modifications within the scope of its main purpose. [Hardenable hot-melt polysilicone composition]

The curable hot melt polysilicone composition of the present invention is a polysilicone composition that can be thermally cured by a silane hydrogenation reaction and has the following components (A) and (B) as main components and contains the following components (C) and (D). The component (A) is a combination of the following components (A1) and (A2) in a mass ratio of (A1): (A2) = 20:80 to 90:10, preferably 35:65 to 90:10, and more preferably 50:50 to 90:10. The component (A1) has a functional group having a carbon-carbon double bond in the molecule and is hardening reactive. The siloxane unit represented by _4/2 is at least 20 mol% of all siloxane units, and is not hot-melting alone and is a solid organic polysiloxane resin at 25°C. The component (A2) does not have a functional group containing a carbon-carbon double bond in the molecule that is hardening reactive, and contains SiO The siloxane unit represented by _4/2 is at least 20 mol% of all siloxane units, is not hot-meltable alone, and is a solid organic polysiloxane resin at 25°C. The component (B) is a linear or branched organic polysiloxane containing a carbon-carbon double bond that is liquid or plastic at 25°C. The component (C) is an organic hydrogenated polysiloxane as a crosslinking agent. The component (D) is a catalyst for silanization reaction that is inactive if not irradiated with high energy rays and becomes active in the composition by irradiating with high energy rays. In addition, in the curable hot-melt polysilicone composition of the present invention, a silanization reaction retarder, i.e., a so-called curing retarder, can be used as desired. In this case, it is preferred to use a curing retarder having a boiling point of 200°C or higher, especially a boiling point of 200°C or higher under atmospheric pressure (1013.25 hPa). Furthermore, depending on the intended use, when it is desired to minimize the surface adhesion of the obtained cured product and to suppress the change in elastic modulus of the cured product at high temperature, it is preferred that the mass reduction rate of component (A) when exposed at 200°C for 1 hour is 2.0 mass % or less. A further feature of the composition of the present invention is that an organic polysiloxane resin that does not have hot melt properties alone is used as components (A1) and (A2), and the composition that also contains components (B) to (D) as a whole has hot melt properties. In addition, in the present invention, unless otherwise specified, "having hot melt properties" means that the softening point of the composition is between 50°C and 200°C, and the composition has a melt viscosity at 150°C (preferably a melt viscosity of less than 1000 Pa·s) and has a flowable property. Therefore, in this specification, the hot melt curable polysilicone composition of the present invention is also referred to as a curable hot melt polysilicone composition. [Meaning of the combination of non-volatile components]

The composition of the present invention is characterized in that components that are difficult to volatilize or components with a low volatile content at atmospheric pressure, especially at atmospheric pressure (1013.25 hPa) and around 100°C are used as components constituting the composition. The reason is that in the production process of the curable hot-melt polysilicone sheet or film of the present invention described later, in order to obtain a sheet or film without voids, the components of the curable polysilicone composition and the composition obtained from the components must be melt-kneaded under reduced pressure and within a temperature range of 50°C to 150°C. By using the components of the present invention, a sheet or film without voids can be produced. Although each component is exposed to a specified temperature for a very short time under reduced pressure, if the active ingredient evaporates in large quantities under the mixing conditions, the problem of not being able to obtain the composition with the designed properties will arise. In particular, for components such as curing retardants that are added in a small amount relative to the total mass of the curable polysilicone composition, the volatility of these components will cause the properties of the composition (curing properties, physical properties of the cured product, etc.) to deviate significantly from the expected values. Therefore, as a constituent component and optional component (E) of the present invention, it is preferred to use a low-volatility component, especially a substantially non-volatile component. [Hot-melting properties and composition of curable polysilicone composition]

The characteristic of the curable polysilicone composition of the present invention is that the composition as a whole has hot melt properties and can flow under heating conditions. It is particularly preferred that the curable polysilicone composition of the present invention has a softening point of 50°C or above and has a melt viscosity at 150°C (preferably a melt viscosity of less than 1000 Pa·s). In addition, in the present invention, as long as the composition as a whole has hot melt properties, the individual components constituting the composition may not have hot melt properties.

More specifically, the curable polysilicone composition of the present invention, i.e., the curable hot-melt polysilicone composition, contains the following components (A), (B), (C) and (D) as essential components in the following ratios, and the composition as a whole exhibits hot-melt properties. (A) an organic polysiloxane resin containing the following components (A1) and (A2) in a mass ratio of 20:80 to 90:10, preferably 35:65 to 90:10, and more preferably 50:50 to 90:10: 100 parts by mass of (A1) an organic polysiloxane resin having a functional group containing a carbon-carbon double bond in the molecule and having a curing reactivity, wherein the siloxane unit represented by SiO _4/2 accounts for at least 20 mol% of all siloxane units, which has no hot melt properties alone and is solid at 25°C; (A2) an organic polysiloxane resin having no functional group containing a carbon-carbon double bond in the molecule and having a curing reactivity, wherein the siloxane unit represented by SiO 4/2 accounts for at least 20 mol% of all siloxane units; (B) 10 to 100 parts by weight of a _linear or branched organic polysiloxane having at least two functional groups containing carbon-carbon double bonds and curing reactivity in the molecule and being liquid or plastic at 25°C; (C) 10 to 100 parts by weight of an organic hydrogenated polysiloxane having at least two hydrogen atoms bonded to silicon in one molecule (the number of hydrogen atoms bonded to silicon atoms is 0.5 to 20.0 for each alkenyl group bonded to silicon atoms in the composition as a whole); and (D) A catalyst for silanization reaction which is inactive if not irradiated with high energy rays and becomes active in the composition by irradiation with high energy rays: an amount sufficient to harden the composition. In addition, the above-mentioned curable polysilicone composition may contain the following component (E) as an optional component: (E) a curing retarder for silanization reaction having a boiling point of 200°C or above under atmospheric pressure, especially under atmospheric pressure. Furthermore, the curable hot-melt polysilicone composition of the present invention may be added with other additives known in the art within the range that the present invention can maintain the target properties.

In addition, the shape of the curable hot-melt polysilicone composition of the present invention is not particularly limited, and it can be formed into a sheet or film shape, and is preferably a sheet or film shape. The following describes the components and optional components contained in the composition of the present invention. [Component (A)]

The curable polysiloxane composition of the present invention comprises as component (A) a combination of the following two organic polysiloxane resins in a mass ratio of 20:80 to 90:10, preferably 35:65 to 90:10, and more preferably 50:50 to 90:10: an organic polysiloxane resin having a functional group with a curing reactivity containing a carbon-carbon double bond, containing a siloxane unit represented by SiO _4/2 as at least 20 mol% of all siloxane units, not showing hot melt properties alone, and being solid at 25°C; and an organic polysiloxane resin having no functional group with a curing reactivity containing a carbon-carbon double bond, containing a siloxane unit represented by SiO The siloxane unit represented by _4/2 is at least 20 mol% of all siloxane units, does not exhibit hot melt properties alone, and is an organic polysiloxane resin that is solid at 25°C. The organopolysiloxane resin may further contain siloxane units represented by R ₃ SiO _1/2 , R ₂ SiO _2/2 , RSiO _3/2 (R represents a monovalent organic group, especially a monovalent hydrocarbon group having 1 to 10 carbon atoms), and hydroxyl or alkoxy groups represented by R ² O _1/2 (R ² is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms), preferably containing siloxane units represented by SiO _4/2 in an amount of at least 20 mol %, preferably 40 mol %, and especially 40 to 90 mol %, of all siloxane units. When the content of the siloxane unit represented by SiO _4/2 is less than 20 mol%, even if the organopolysiloxane resin contains a large amount of other branched siloxane units (such as RSiO _3/2 ), the technical effect of the present invention may not be achieved.

The organic polysiloxane resin of component (A) is preferably an organic polysiloxane resin mixture containing component (A1) and component (A2) in a mass ratio of 20:80 to 90:10, more preferably 35:65 to 90:10, and more preferably 50:50 to 90:10 (component (A1): component (A2)): (A1) an organic polysiloxane resin having a functional group with a carbon-carbon double bond in the molecule, containing a siloxane unit represented by SiO _4/2 accounting for at least 20 mol% of all siloxane units, not having hot melt properties alone, and being solid at 25°C; and (A2) an organic polysiloxane resin having no functional group with a carbon-carbon double bond in the molecule, containing a siloxane unit represented by SiO 4/2 The siloxane unit represented by _4/2 is at least 20 mol% of all siloxane units, is not hot-melting alone, and is an organic polysiloxane resin that is solid at 25°C. In addition, the curing reactivity means that it can undergo a silanization reaction with the organic hydrosiloxane of component (C), thereby curing the entire composition.

The above-mentioned component (A) alone does not exhibit hot melt properties, but by using the component (B) described later within a specified quantitative ratio, the composition of the present invention as a whole can be made hot meltable. [Organic polysiloxane resin (A1) having a curing reactive functional group]

The above-mentioned component (A1) is one of the main agents of the present composition and is an organic polysiloxane resin containing siloxane units represented by SiO _4/2 accounting for at least 20 mol% of all siloxane units, which alone does not have hot-melt properties and has a curing reactive functional group containing a carbon-carbon double bond in the molecule.

The component (A1) must have a hardening reactive group containing a carbon-carbon double bond in the molecule. Such a hardening reactive group is a silylation-reactive functional group, which can form a hardened material by a silylation crosslinking reaction with the component (C). Such a hardening reactive group is preferably an alkenyl group, and more preferably a vinyl group or a hexenyl group.

Component (A1) is an organopolysiloxane resin that does not have hot melt properties alone and is solid in the absence of a solvent. Here, the term "does not have hot melt properties" means that the organopolysiloxane resin as component (A1) does not melt when heated below 200°C, and specifically, does not have a softening point and melt viscosity below 200°C. In order to allow component (A1) to exhibit the above physical properties, it is preferred that the functional group in the organic polysiloxane resin is a monovalent hydrocarbon group having 1 to 10 carbon atoms, especially a functional group selected from an alkyl group having 1 to 10 carbon atoms such as a methyl group, and substantially does not contain an aromatic group such as a phenyl group, for example, the ratio of aromatic groups to all organic groups bonded to silicon is less than 5 mol%, more preferably less than 2 mol%, and it is particularly preferred that it contains no aromatic groups at all. When component (A1) contains a large amount of aromatic groups such as phenyl groups as organic groups, the component alone may have hot melt properties, and the effect of reinforcing and curing the material unique to the SiO _4/2 group may be reduced.

Preferably, the functional group of the organopolysiloxane resin of component (A1) bonded to the silicon atom is a group selected from alkenyl groups such as methyl and vinyl, preferably 70 mol% to 99 mol% of all organic groups bonded to the silicon atom are methyl groups, more preferably 80 to 99 mol% are methyl groups, and particularly preferably 88 to 99 mol% are methyl groups, and the other organic groups bonded to the silicon atom are alkenyl groups such as vinyl groups. Within this range, component (A1) alone does not have hot melt properties, and is useful as a component that makes the cured product obtained from the curable polysilicone composition of the present invention particularly excellent in coloration resistance at high temperatures. In addition, the organopolysiloxane resin of component (A1) may also contain a small amount of hydroxyl or alkoxy groups.

Component (A1) is an organic polysiloxane resin that is solid in the absence of a solvent, and is characterized in that the siloxane unit represented by SiO _4/2 in the molecule is at least 20 mol% of all siloxane units. Preferably, the SiO _4/2 unit is at least 40 mol% of all siloxane units, more preferably at least 50 mol%, and especially in the range of 50 to 90 mol%. In addition, the organic group R possessed by the organic polysiloxane resin of component (A1) is a monovalent organic group, preferably a monovalent alkyl group having 1 to 10 carbon atoms, especially a functional group selected from alkyl and alkenyl groups having 1 to 10 carbon atoms such as methyl, and from the viewpoint of technical effects, as mentioned above, the group R is preferably substantially free of aromatic groups such as phenyl. Preferably ingredient (A1)

(A1-1) is an organic polysiloxane resin represented by the following average unit formula, which is not hot-melting alone and is solid at 25°C: (R ¹ ₃ SiO _1/2 ) _a (R ¹ ₂ SiO _2/2 ) _b (R ¹ SiO _3/2 ) _c (SiO _4/2 ) _d (R ² O _1/2 ) _e (wherein each R ¹ is independently a monovalent hydrocarbon group having 1 to 10 carbon atoms, wherein 1 to 12 mol% of all R ¹ in one molecule are alkenyl groups; each R ² is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; a, b, c, d and e are numbers satisfying the following: 0.10≦a≦0.60, 0≦b≦0.70, 0≦c≦0.80, 0≦d≦0.65, 0≦e≦0.05, wherein c+d＞0.20 and a+b+c+d＝1).

In the above average unit formula, each R ¹ is independently a monovalent hydrocarbon group having 1 to 10 carbon atoms, for example, a group selected from the group consisting of alkyl groups such as methyl; alkenyl groups such as vinyl and 1-hexenyl; aryl groups such as phenyl; and aralkyl groups. Furthermore, 1 to 12 mol% of all R ¹ in one molecule are alkenyl groups, preferably 2 to 10 mol% of all R ¹ in one molecule are alkenyl groups, and vinyl groups are particularly preferred. When the content of alkenyl groups is less than the lower limit of the aforementioned range, the mechanical strength (hardness, etc.) of the obtained cured product may be insufficient. On the other hand, if the content of alkenyl groups is less than the upper limit of the aforementioned range, the composition containing this component can achieve good hot melt properties as the composition as a whole. In addition, each R ¹ is preferably a functional group selected from an alkyl group having 1 to 10 carbon atoms, such as a methyl group, and an alkenyl group, such as a vinyl group and a hexenyl group. From the viewpoint of the technical effect of the present invention, R ¹ is preferably substantially free of an aryl group, such as a phenyl group. When a large amount of aryl groups, such as a phenyl group, are contained, component (A) itself will have a hot melt property, and the technical effect of the present invention may not be achieved. In addition, for the cured product, the effect of reinforcing the cured product, which is unique to the SiO _4/2 group, may be reduced.

In the above formula, R ² is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. Examples of the alkyl group of R ² include a methyl group and the like. The group R ² O _1/2 containing the R ² is equivalent to the hydroxyl group or alkoxy group of the organopolysiloxane resin of component (A).

In the above formula, a is the number representing the ratio of the siloxane unit of the general formula: R ¹ ₃ SiO _1/2 . a satisfies 0.1≦a≦0.60, preferably 0.15≦a≦0.55. If a is above the lower limit of the aforementioned range, the composition containing this component can achieve good hot melt performance as the composition as a whole. On the other hand, if a is below the upper limit of the aforementioned range, the mechanical strength (hardness, elongation, etc.) of the cured product obtained by curing the curable polysilicone composition of the present invention will not become too low.

In the above formula, b is the number representing the ratio of the siloxane unit of the general formula: R ¹ ₂ SiO _2/2 . b satisfies 0≦b≦0.70, preferably 0≦b≦0.60. If b is below the upper limit of the above range, the composition containing this component can achieve good hot melt performance as the composition as a whole, and can obtain a composition with less adhesion at room temperature.

In the above formula, c is the number representing the ratio of the siloxane unit of the general formula: R ³ SiO _3/2 . c satisfies 0≦c≦0.80, preferably 0≦c≦0.75. If c is below the upper limit of the above range, the composition containing this component can achieve good hot melt properties as a whole composition, and can obtain a composition with little adhesion and low or no viscosity at room temperature. In the present invention, c can be 0, and c is preferably 0.

In the above formula, d is a number representing the ratio of siloxane units of the formula SiO _4/2 , and must be 0.00≦d≦0.65, preferably 0.20≦d≦0.65, and particularly preferably 0.25≦d≦0.65. If d is within the above numerical range, the composition containing this component can achieve good hot-melt properties as a whole, so that the hardened material obtained by hardening the composition is relatively hard and has sufficient softness for practical use.

In the present invention, in the above formula, c or d may be 0, but c+d>0.20. When the value of c+d is less than 0.20, the good hot-melt performance of the composition as a whole may not be achieved, and the technical effect of the present invention may not be fully achieved.

In the above formula, e is a number representing the ratio of the unit of the general formula: R ² O _1/2 , which refers to the hydroxyl group or alkoxy group bonded to the silicon atom that may be contained in the organic polysiloxane resin. e is 0≦e≦0.05, preferably 0≦e≦0.03. If e is below the upper limit of the range, a material having good hot melt properties as a whole composition can be obtained. In addition, in the above formula, the sum of the siloxane units, i.e., the sum of a, b, c and d, is equal to 1.

Component (A1) is an organic polysiloxane resin having the above characteristics. Since it is solid at room temperature, it is preferably used in a state of being dissolved in a solvent or a solvent mixture selected from the group consisting of aromatic hydrocarbons, ethers, polysiloxanes, esters, ketones, etc. in order to be physically mixed with the component (B) described later. The solvent used here can be efficiently removed in the process described later. [Component (A2)]

Component (A2) is one of the main agents of the present composition and is an organic polysiloxane resin which does not have hot-melting properties or a functional group that has a curing reaction, and is solid at 25°C. It is used together with the above-mentioned components (A1) and (B) within a prescribed amount to achieve hot-melting properties of the entire curable polysilicone composition and excellent stress-relieving properties of the cured product obtained by curing the curable polysilicone composition.

Component (A2) is an organopolysiloxane resin that does not have hot melt properties alone and is solid in the absence of a solvent. Here, the term "does not have hot melt properties" means that the organopolysiloxane resin as component (A2) does not melt when heated below 200°C, and specifically, does not have a softening point and melt viscosity below 200°C. In order to allow component (A2) to exhibit such physical properties, it is preferred that the functional group in the organic polysiloxane resin is a monovalent hydrocarbon group having 1 to 10 carbon atoms, especially a functional group selected from an alkyl group having 1 to 10 carbon atoms such as a methyl group, and substantially does not contain an aromatic group such as a phenyl group, for example, the ratio of aromatic groups to all organic groups bonded to silicon is less than 5 mol%, more preferably less than 2 mol%, and it is particularly preferred that it contains no aromatic groups at all. When component (A2) contains a large amount of aromatic groups such as phenyl groups as organic groups, the component may have hot melt properties, and the reinforcing curing effect unique to the SiO _4/2 group may be reduced.

Component (A2) is a solid organic polysiloxane resin at 25°C, similarly to component (A1), and contains siloxane units represented by SiO _4/2 accounting for at least 20 mol% of all siloxane units, and is characterized in that the molecule does not contain any functional group containing a carbon-carbon double bond and having curing reactivity. That is, component (A2) is characterized in that it does not contain an olefinic group such as a vinyl group as a functional group in the organic polysiloxane resin. As the group possessed by the organopolysiloxane resin as component (A2), there can be mentioned monovalent hydrocarbon groups having 1 to 10 carbon atoms, especially alkyl groups having 1 to 10 carbon atoms such as methyl groups. The organopolysiloxane resin preferably does not substantially contain aromatic groups such as phenyl groups, for example, the ratio of aromatic groups to all organic groups bonded to silicon is 5 mol% or less, more preferably 2 mol% or less, and most preferably does not contain aromatic groups at all.

It is preferred that the functional group bonded to the silicon atom in component (A2) is an alkyl group having 1 to 10 carbon atoms, such as a methyl group. It is preferred that 70 mol% to 100 mol% of all organic groups bonded to the silicon atom are methyl groups, more preferably 80 to 100 mol% are methyl groups, and particularly preferably 88 to 100 mol% are methyl groups. Within this range, component (A2) alone can be a component that does not exhibit hot melt properties, contains a siloxane unit represented by SiO _4/2 , and has a particularly excellent reinforcing effect on the cured product. In addition, the organic polysiloxane resin of component (A2) may also contain a small amount of hydroxyl or alkoxy groups.

Component (A2) does not have a curing reactive functional group containing a carbon-carbon double bond in the molecule, so even if it is combined with the organic hydrogenated polysiloxane of component (C), it will not form a cured product. However, it has the following effects: improving the hot melt properties of the curable polysiloxane composition of the present invention as a whole, and reinforcing the cured product obtained by curing the curable polysiloxane composition. In addition, by using it together with component (A1) having a curing reactive functional group as needed, the heating melting characteristics of the obtained curable polysiloxane composition and the physical properties of the composition after curing can be adjusted.

The component (A2) is an organic polysiloxane resin which is solid at 25°C in the absence of a solvent, and is characterized in that the siloxane unit represented by SiO _4/2 as a branched siloxane unit in the molecule is at least 20 mol% of all siloxane units. Preferably, the organic _polysiloxane of the component (A2) contains at least 40 mol% of all siloxane units, more preferably 50 mol% or more, and particularly preferably in the range of 50 to 65 mol%.

Preferably, component (A2) is an organic polysiloxane resin (A2-1) represented by the following average unit formula and which alone does not have a hot melt property: (R ³ ₃ SiO _1/2 ) _f (R ³ ₂ SiO _2/2 ) _g (R ³ SiO _3/2 ) _h (SiO _4/2 ) _i (R ² O _1/2 ) _j (wherein each R ³ is independently a monovalent hydrocarbon group having 1 to 10 carbon atoms and not containing a carbon-carbon double bond; R ² is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; f, g, h, i and j are numbers satisfying the following: 0.35≦f≦0.55, 0≦g≦0.20, 0≦h≦0.20, 0.45≦i≦0.65, 0≦j≦0.05, and f+g+h+i=1).

In the above average unit formula, each R ³ is independently a monovalent alkyl group having 1 to 10 carbon atoms and not containing a carbon-carbon double bond, for example, a group selected from the group consisting of alkyl groups such as methyl; aryl groups such as phenyl; and aralkyl groups such as benzyl. Here, it is preferred that 70 mol% or more of all R ³ in a molecule are alkyl groups having 1 to 10 carbon atoms such as methyl, especially methyl. From the perspective of industrial production and the technical effect of the invention, it is particularly preferred that 88 mol% or more are alkyl groups having 1 to 10 carbon atoms, especially methyl. On the other hand, R ³ is preferably substantially free of aryl groups such as phenyl. When a large amount of aromatic groups such as phenyl groups are contained, the component (A2) itself becomes hot-melting, and the technical effects of the present invention may not be achieved. In addition, the coloration resistance of the hardened polysilicone composition of the present invention at high temperatures may deteriorate.

In the above formula, R ² is as described above. When R ² is an alkyl group, an example of the alkyl group is a methyl group.

In the above formula, f is a number representing the ratio of siloxane units of the general formula: R ³ ₃ SiO _1/2 . f satisfies 0.35≦f≦0.55, preferably 0.40≦f≦0.50. If f is above the lower limit of the aforementioned range, the curable polysilicone composition containing this component can achieve good hot melt performance as the composition as a whole. On the other hand, if f is below the upper limit of the aforementioned range, the mechanical strength (hardness, etc.) of the obtained cured product will not become too low.

In the above formula, g is a number representing the ratio of siloxane units of the general formula: R ³ ₂ SiO _2/2 . g satisfies 0≦g≦0.20, preferably 0≦g≦0.10. If g is below the upper limit of the range, the curable polysilicone composition containing this component can achieve good hot melt properties as a whole composition, and can obtain a composition with less adhesion at room temperature. In the present invention, g can be 0, and g is preferably 0.

In the above formula, h is a number representing the ratio of siloxane units of the general formula: R ³ SiO _3/2 . h satisfies 0≦h≦0.20, preferably 0≦h≦0.10. If h is below the upper limit of the range, the curable polysilicone composition containing this component can achieve good hot melt properties as a whole composition, and can obtain a composition with less adhesion at room temperature. In the present invention, h can be 0, and h is preferably 0.

In the above formula, i is a number representing the ratio of the siloxane unit of SiO _4/2 , and must be 0.45≦i≦0.65, and preferably 0.50≦i≦0.65. When i is within this numerical range, the curable polysilicone composition containing this component can achieve good hot melt performance as the whole composition, so that the mechanical strength of the cured product obtained by curing the curable polysilicone composition is excellent, and the composition can be realized as a whole composition with good non-adhesive handling properties.

In the above formula, j is a number representing the ratio of the unit of the general formula: R ² O _1/2 , which refers to the hydroxyl group or alkoxy group bonded to the silicon atom that may be contained in the organic polysiloxane resin. j satisfies 0≦j≦0.05, preferably 0≦j≦0.03. If j is below the upper limit of the above range, good hot melt performance as a whole of the curable polysiloxane composition can be achieved. In addition, in the above formula, the sum of each siloxane unit, that is, the sum of f, g, h and i, is equal to 1.

Component (A2) is an organic polysiloxane resin having the above characteristics, and is the same as the aforementioned component (A1) in terms of handling. That is, since component (A2) is solid at room temperature (e.g., 25°C), it is used in a state of being dissolved in the above solvent or solvent mixture in order to be mixed with component (B) in the same manner as component (A1), and then the solvent can be removed to prepare a curable polysilicone composition. [Removal of volatile low molecular weight components in component (A)]

Regarding the components (A1) and (A2), volatile low molecular weight components are generated during their respective production processes. Specifically, the volatile low molecular weight components are M ₄ Q structures. In order to apply the curable polysiloxane composition of the present invention to lamination on a substrate such as a semiconductor, it is preferred to remove the M 4 Q structure from the organic polysiloxane resin as far as possible before the raw materials are prepared before lamination on the substrate and curing the curable polysiloxane composition in the molding step of curing the curable _polysiloxane composition. As methods for removing the M ₄ Q structure from the organopolysiloxane resin, there can be cited: a method of removing the M _{4 Q structure by drying the organopolysiloxane resin in a drying oven or the like after obtaining the organopolysiloxane resin in a particle form during the production process of the organopolysiloxane resin; a method of removing the M 4} Q structure together with the organic solvent using a double-screw kneading mill described later. [Mass ratio of component (A1) to component (A2) in component (A)]

In order to make the composition as a whole hot-melt, component (A2), or a mixture of component (A1) and component (A2), must be mixed with component (B) described later in a prescribed ratio. The ratio of component (A1) to component (A2) can be in the range of 20:80 to 90:10, preferably in the range of 35:65 to 90:10, and more preferably in the range of 50:50 to 90:10. Component (A2) itself does not have a curing reactive functional group and therefore has no curing property. By using component (A2) in combination with component (A1) in this composition, the storage modulus, loss modulus, and tanδ calculated from the ratio of the hardened material obtained by hardening this hardening composition can be adjusted to a certain extent, thereby achieving a better elastic modulus, flexibility, and stress relaxation of the hardened material. In addition, even if component (A1) is not added and component (A2) is combined with component (B), a hardening hot-melt polysilicone composition with the characteristics required in the present invention can be prepared. [Component (B)]

Component (B) is one of the main agents of the curable polysiloxane composition and is a linear or branched organic polysiloxane that is liquid or plastic at 25°C and has at least two curable reactive functional groups containing carbon-carbon double bonds in the molecule. This curable reactive chain organic polysiloxane can be mixed with the solid organic polysiloxane resin of the aforementioned component (A) to make the entire composition exhibit hot melt properties.

Component (B) must have a hardening reactive functional group containing a carbon-carbon double bond in the molecule. Such hardening reactive functional group has silylation reactivity and forms a hardened material by cross-linking reaction with other components. Such hardening reactive functional group is an alkenyl group like that of component (A1), preferably a vinyl group or a hexenyl group.

Component (B) is a linear or branched organic polysiloxane that is liquid or plastic at 25°C (room temperature). By mixing with component (A) that is solid at room temperature, the entire composition can exhibit hot-melt properties. The chemical structure of the organic polysiloxane of component (B) may be a linear chain or a branched chain organic polysiloxane having a small number of branched siloxane units (for example, a T unit represented by the general formula: R ⁴ SiO _3/2 (R ⁴ is independently a monovalent hydrocarbon group having 1 to 10 carbon atoms) or a Q unit represented by SiO _4/2 ), but preferably is a linear diorganopolysiloxane (B1) represented by the following structural formula: R ⁴ ₃ SiO(SiR ⁴ ₂ O) _k SiR ⁴ ₃ (wherein each R ⁴ is independently a monovalent hydrocarbon group having 1 to 10 carbon atoms, wherein at least two of the R ⁴ groups in one molecule are alkenyl groups, and k is a number from 20 to 5,000). Preferably, it is a linear diorganopolysiloxane having an alkenyl group, especially a vinyl group, at each end of the molecular chain.

In the above formula, each R ⁴ is independently a monovalent alkyl group having 1 to 10 carbon atoms, and the same groups as above can be exemplified. In addition, at least two of the R ⁴ in one molecule are alkenyl groups, preferably vinyl groups. In addition, each R ⁴ is preferably a functional group selected from the group consisting of alkyl groups having 1 to 10 carbon atoms such as methyl groups, and alkenyl groups such as vinyl groups and hexenyl groups. It is preferred that at least two of all R ⁴ in each molecule are alkenyl groups, and the remaining R ⁴ are methyl groups. In addition, from the perspective of the technical effect of the invention, R ⁴ is preferably substantially free of aryl groups such as phenyl groups. When a large amount of aryl groups such as phenyl groups are contained, the coloring resistance of the cured product obtained from the curable polysilicone composition at high temperatures may deteriorate. It is particularly preferred that there is an alkenyl group such as vinyl group at each end of the molecular chain, and the other R ⁴ is methyl group.

In the above formula, k is 20 to 5,000, preferably 30 to 3,000, and particularly preferably 45 to 800. If k is above the lower limit of the above range, a curable polysilicone composition with less adhesion at room temperature can be obtained. On the other hand, if k is below the upper limit of the above range, good hot melt performance as the whole curable polysilicone composition can be achieved.

Here, in order to make the composition as a whole exhibit hot melt properties, the content of the linear or branched organic polysiloxane component (B) is in the range of 10 to 100 parts by mass, preferably in the range of 10 to 70 parts by mass, and more preferably in the range of 15 to 50 parts by mass, relative to 100 parts by mass of the component (A) as the organic polysiloxane resin. If the content of the component (B) is within the above range, the obtained curable polysilicone composition exhibits good hot melt properties, and the mechanical strength of the cured product obtained by curing the curable polysilicone composition can be increased, and the adhesion of the obtained curable polysilicone composition at room temperature can be reduced, thereby improving the handling workability of the composition. [Component (C)]

Component (C) is an organic hydrogenated polysiloxane which can crosslink with the carbon-carbon double bonds contained in the above-mentioned components (A) and (B) in the presence of a catalyst for silylation reaction and has at least two hydrogen atoms bonded to silicon atoms in one molecule, and is a component for hardening the composition.

The structure of the organic hydrogenated polysiloxane used as a crosslinking agent is not particularly limited and may be linear, branched, cyclic or resinous. That is, component (C) may be an organic hydrogenated polysiloxane containing a hydrogenated organic silaneoxy unit represented by HR ₂ SiO _1/2 ( ^MH unit, R is independently a monovalent organic group) and a hydrogenated organic silaneoxy unit represented by HRSiO _2/2 ( ^DH unit, R is independently a monovalent organic group).

On the other hand, when the curable polysiloxane composition is used in the forming step, since the content of the curing reactive functional group containing a carbon-carbon double bond in the composition is small, from the viewpoint of the curing speed, its formability and curability, the organohydrogenated polysiloxane is preferably an organohydrogenated polysiloxane resin comprising a branch unit which is a monoorganosiloxy unit (T unit, R is a monovalent organic group or a hydrogen atom bonded to a silicon atom) represented by RSiO _3/2 or a siloxy unit (Q unit) represented by SiO _4/2 , and having at least two hydrodisorganosiloxy units ( ^MH units, R is independently a monovalent organic group) represented by HR ₂ SiO _1/2 in the molecule and having ^MH units at the molecular ends.

A particularly preferred organic hydrogenated polysiloxane is an organic hydrogenated polysiloxane represented by the following average composition formula (1): (R ⁴ ₃ SiO _1/2 ) _a (R ⁵ ₂ SiO _2/2 ) _b (R ⁵ SiO _3/2 ) _c (SiO _4/2 ) _d (R ² O _1/2 ) _e (1) (wherein R ⁴ is independently a hydrogen atom or an unsubstituted or substituted monovalent hydrocarbon group having 1 to 12 carbon atoms and not containing an aliphatic unsaturated bond, R ⁵ is independently a unsubstituted or substituted monovalent hydrocarbon group having 1 to 12 carbon atoms and not containing an aliphatic unsaturated bond, and all R At least two of ⁴ are hydrogen atoms, and a, b, c and d are numbers that satisfy the following conditions: 0.01≦a≦0.6, 0≦b, 0≦c≦0.9, 0≦d≦0.9, and a+b+c+d=1 and c+d≧0.2) In addition, the organohydrogenated polysiloxane may be arbitrarily the following: having a characteristic that the mass reduction rate relative to the mass before exposure after exposure to 100°C under atmospheric pressure for 1 hour is less than 10 mass %.

In the above formula, each R ⁴ is the same or different monovalent hydrocarbon group or hydrogen atom having 1 to 12 carbon atoms and not having an aliphatic unsaturated carbon bond, wherein at least two, preferably at least three R ⁴ in one molecule are hydrogen atoms. From an industrial point of view, the monovalent hydrocarbon group of R ⁴ other than a hydrogen atom is preferably a methyl group or a phenyl group.

In the formula, R ⁵ is a monovalent hydrocarbon group having 1 to 12 carbon atoms and having no aliphatic unsaturated carbon bond, and examples thereof include the same monovalent hydrocarbon group as described above for R ^4. R ⁵ is preferably a group selected from methyl and phenyl groups.

In the formula, a, b, c and d are numbers satisfying the following conditions: 0.01≦a≦0.6, 0≦b, 0≦c≦0.9, 0≦d≦0.9, and a+b+c+d=1 and c+d≧0.2. Specific examples include ^MHMT resin, ^MHT resin, ^MHMTQ resin, ^MHMQ resin, ^MHDQ resin and ^MHQ resin. In the symbols of the above resins, M, D, T and Q represent M unit, D unit, T unit and Q unit, respectively, and ^MH represents M unit having hydrogen atom.

In the above formula, R ² is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. Examples of the alkyl group of R ² include a methyl group and the like. The group R ² O _1/2 containing the R ² is equivalent to the hydroxyl group or alkoxy group of the organic hydrogenated polysiloxane of component (C).

In the above formula, e is a number representing the ratio of the unit of the general formula: R ² O _1/2 , which represents a hydroxyl group or alkoxy group bonded to a silicon atom that may be contained in the organic polysiloxane resin. e satisfies 0≦e≦0.05, preferably 0≦e≦0.03. In addition, as mentioned above, the sum of the siloxane units in the above formula (1), i.e., the sum of a, b, c and d, is equal to 1.

The component (C) is preferably an organic hydrogenated polysiloxane represented by the following average composition formula (2). (HR ⁶ ₂ SiO _1/2 ) _e (R ⁶ ₂ SiO _2/2 ) _f (SiO _4/2 ) _g (2) In the formula (2), R ⁶ is independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 12 carbon atoms and not containing an aliphatic unsaturated bond, and e, f and g are numbers satisfying the following conditions: 0.01≦e≦0.6, 0≦f≦0.9, 0.2≦g≦0.9 and e+f+g=1. Specific examples of the monovalent hydrocarbon group are the same as those exemplified as specific examples of the monovalent hydrocarbon group represented by R ⁴ in the above average composition formula (1). R ⁶ are each independently preferably a group selected from methyl and phenyl.

In addition, component (C) is preferably an organic hydrogenated polysiloxane represented by the following average formula (3). (HR ⁷ ₂ SiO _1/2 ) _h (R ⁷ ₂ SiO _2/2 ) _i (R ⁸ SiO _3/2 ) _j (3) In formula (3), R ⁷ and R ⁸ are independently an unsubstituted or substituted monovalent hydrocarbon group having 1 to 12 carbon atoms and not containing an aliphatic unsaturated bond, at least 10 mol% of all R ⁸ are aromatic groups, and h, i and j are numbers that satisfy the following conditions: 0.01≦h≦0.6, 0≦i≦0.9, 0.2≦j≦0.9 and h+i+j=1. Specific examples of the monovalent hydrocarbon group are the same as those exemplified as specific examples of the monovalent hydrocarbon group represented by R ⁴ in the above average composition formula (1). Provided that at least 10 mol% of all R ⁸ are phenyl groups, R ⁸ are preferably independently selected from methyl and phenyl groups.

The organic hydrogenated polysiloxane represented by the average composition formula (2) and the organic hydrogenated polysiloxane represented by the average composition formula (3) can be used alone or in combination.

The content of the organic hydrogenated polysiloxane of component (C) in the curable polysiloxane composition of the present invention is an amount sufficient to cure the curable polysiloxane composition. The amount of hydrogen atoms bonded to silicon atoms in the organic hydrogenated polysiloxane of component (C) relative to the curing reactive functional groups containing carbon-carbon double bonds (e.g., alkenyl groups such as vinyl groups) in components (A) and (B) is preferably such that the number of hydrogen atoms bonded to silicon atoms is in the range of 0.5 to 20.0, particularly in the range of 1.0 to 10, relative to each alkenyl group bonded to silicon atoms contained in the curable polysiloxane composition as a whole.

On the other hand, the above-mentioned organohydrogenated polysiloxane, regardless of its structure, is preferably a component that is difficult to volatilize under atmospheric pressure, especially under atmospheric pressure (1013.25 hPa) and at about 100°C. The reason is that in the production process of the curable hot-melt polysilicone sheet or film of the present invention described later, in order to obtain a sheet or film without voids, the components of the curable polysilicone composition and the composition obtained from the components must be melt-kneaded under reduced pressure and in a temperature range of 50°C to 150°C. By using the components of the present invention, a sheet or film without voids can be produced. Although each component is exposed to the specified temperature under reduced pressure for a very short time, if the active ingredients volatilize in large quantities under the kneading conditions, the problem of not being able to obtain the composition with the designed properties will arise. In particular, since the amount of organic hydrogenated polysiloxane used as a crosslinking agent is relatively small relative to the total mass of the curable polysiloxane composition, the volatilization of these components will cause the properties of the composition (curing properties, physical properties of the cured product, etc.) to deviate significantly from the expected values. Therefore, component (C) must be less volatile. Specifically, the mass reduction rate after exposure to 100°C under atmospheric pressure for 1 hour relative to the mass reduction before exposure can be less than 10 mass%, which is preferably the case depending on the application. [Component (D)]

Component (D) is one of the characteristic components of the curable polysilicone composition of the present invention and is a catalyst for silanization reaction. It is used to crosslink the silanization-reactive carbon-carbon double bonds contained in components (A) and (B) with the hydrogen atoms, i.e., Si-H groups, of the bonded silicon atoms contained in component (C) through silanization reaction, thereby curing the curable polysilicone composition of the present invention. Specifically, it is a catalyst for silanization reaction that is inactive if not irradiated with high energy rays, but becomes active in the composition by irradiating with high energy rays. Component (D) is called a so-called high energy ray activated catalyst or a photo-activated catalyst, which is well known in the art. By using component (D), the entire composition can be cured even at low temperatures by being triggered by irradiation with high-energy rays, and has excellent storage stability and is easy to control the reaction, thereby achieving excellent handling properties.

Examples of high energy rays include ultraviolet rays, gamma rays, X rays, alpha rays, electron beams, etc. In particular, ultraviolet rays, X rays, and electron beams irradiated from commercially available electron beam irradiation devices can be cited. Among them, ultraviolet rays are preferred in terms of catalyst activation efficiency, and ultraviolet rays with a wavelength range of 280 to 380 nm are preferred in terms of industrial utilization. In addition, the irradiation amount varies depending on the type of high energy ray-activated catalyst. In the case of ultraviolet rays, the cumulative irradiation amount at a wavelength of 365 nm is preferably in the range of 100 mJ/ ^cm2 to 100 J/ ^cm2 .

Specific examples of the component (D) are preferably (methylcyclopentadienyl)trimethylplatinum (IV) and bis(2,4-pentanedionato)platinum (II) in terms of general versatility and availability.

The content of component (D) is the amount required to harden the composition, preferably the amount of metal atoms in the catalyst in the range of 1 to 500 ppm by mass relative to the composition, preferably the amount in the range of 5 to 200 ppm. [Component (E)]

The curable polysilicone composition of the present invention may further contain a curing retarder (E) in addition to the above-mentioned components (A) to (D).

The structure of the curing retarder is not particularly limited, but preferably has a boiling point of 200°C or higher under atmospheric pressure. The reason is that when the raw materials are melt-kneaded under reduced pressure in the production process of the curable silicone composition sheet described below, if a compound with a low boiling point is used as the curing retarder, part or all of the curing retarder will volatilize during the melt-kneading step, and there is a concern that the target curing retarding effect of the curable silicone composition cannot be obtained.

The curing retarder of the present invention is not particularly limited, and examples thereof include: 2-methyl-3-butyn-2-ol, 1-ethynyl-1-cyclohexanol and other acetylenic alcohols; enyne compounds; low molecular weight siloxanes containing alkenyl groups; methyltri(1,1-dimethylpropynyloxy)silane, vinyltri(1,1-dimethylpropynyloxy)silane and other acetylenic silanes. Among these, compounds having a boiling point of 200°C or above under atmospheric pressure are particularly preferred. [Other additives]

In addition to the above-mentioned components, the curable hot-melt polysilicone composition of the present invention may also contain materials known in the art as additives that can be used in polysilicone compositions. The following additives can be cited as usable additives, but are not limited thereto.

Fillers can be used as additives for the purpose of improving the mechanical and physical properties of the hardened material obtained from the hardening hot-melt polysilicone composition of the present invention or improving the flame retardancy. As fillers, inorganic fillers, organic fillers and mixtures thereof can be cited. As for the function of the filler, one or more fillers selected from reinforcing fillers, thermally conductive fillers, electrically conductive fillers, pigments (especially white pigments), fluorescent materials, etc. can be added to the hardening hot-melt polysilicone composition of the present invention. When fillers are used, it is preferred to select the type and amount of fillers within the range in which the curable hot-melt polysilicone composition of the present invention can be melt-kneaded and within the range in which the properties of the curable hot-melt polysilicone composition of the present invention (e.g., curing properties, mechanical and physical properties after curing, weather resistance, etc.) can be affected. In a preferred embodiment of the curable hot-melt polysilicone composition of the present invention, the curable hot-melt polysilicone composition does not contain fillers.

Furthermore, the composition of the present invention may contain an adhesive imparting agent as another optional component within the scope not impairing the object of the present invention.

In addition, the composition may contain heat resistant agents such as iron oxide (red iron), calcium oxide, calcium dimethyl silanol, calcium fatty acid, calcium hydroxide, zirconium compounds, and dyes, pigments other than white, flame retardant agents, etc. as other optional components within the scope that does not impair the purpose of the present invention.

The curable hot-melt polysilicone composition of the present invention can be used in the form of granules, pellets, sheets or films.

This composition can be formed into a sheet or film for use. For example, a sheet or film formed of the curable polysilicone composition of the present invention with an average thickness of 10 to 1000 µm has hot melt properties and heat curing properties at high temperatures, so it has excellent handling properties and melting characteristics, and is particularly advantageous for use in compression molding, etc. In this case, it is preferred to form a composition containing all of components (A) to (D) including component (D) into a sheet or film. [Laminates containing curable hot melt polysilicone compositions and use as film adhesives/sealants]

The curable hot-melt polysilicone composition can be used in the form of a sheet or a film, and can be used in particular as a laminate having the following structure: a sheet material formed of the curable hot-melt polysilicone composition is inserted between two film substrates having a peeling layer. When the sheet material formed of the curable hot-melt polysilicone composition is used as an adhesive or a sealant, the film substrate having a peeling layer (usually referred to as a peeling film) can be peeled off from the sheet material. Hereinafter, the laminate is also referred to as a peelable laminate.

The manufacturing method of the above-mentioned exfoliative laminate is not particularly limited. For example, a method comprising the following steps can be cited: Step 1: a step of mixing the components of the above-mentioned curable hot-melt polysilicone composition; Step 2: a step of heating and melting the mixture obtained in step 1 while kneading; Step 3: a step of laminating the heated and molten mixture obtained in step 2 between two exfoliation films having at least one exfoliation surface in a manner that the above-mentioned mixture is in contact with the exfoliation surface to form a laminate; Step 4: Pressurizing the laminate obtained in step 3 between rollers, and rolling the mixture inserted between two peeling films, thereby forming a hardening hot-melt polysilicone composition sheet or film having a specific film thickness. In addition, a roller with a cooling or temperature regulating function can be used in step 4 as desired. Moreover, after step 4, a step of cutting the laminate containing the hardening hot-melt polysilicone composition sheet or film can be added. In addition, the thickness of the peeling film is not particularly limited, so in addition to what is usually called a film, it also includes what is called a sheet. However, in this specification, regardless of its thickness, it is called a peeling film. [Hardenable hot-melt polysilicone composite sheet]

The hardening hot-melt polysilicone composition sheet obtained by the manufacturing method of the present invention is a hardening polysilicone composition containing the above-mentioned components (A) to (D) and, if necessary, the component (E), and has hot melt properties. The hardening hot-melt polysilicone composition sheet of the present invention can be used as an adhesive material, sealant and/or bonding agent with heat-melting properties. In particular, the hardening hot-melt polysilicone composition sheet has excellent formability, gap filling properties and adhesion, and can be used as a die bonding film or film bonding agent. In addition, it can also be suitably used as a hardening hot-melt polysilicone composition sheet for compression molding or pressure molding.

Specifically, the hardening hot-melt polysilicone composition sheet obtained by the manufacturing method of the present invention is peeled off from the peeling film and arranged at the required position of the semiconductor, etc., and a film bonding layer that can fill the unevenness or gaps is formed on and between the adherends, thereby temporarily fixing, arranging and bonding the adherends. Furthermore, the hardening hot-melt polysilicone composition layer is heated to above 150°C to harden it, and a hardened material of the hardening polysilicone sheet is formed between the adherends, thereby bonding the adherends. In addition, the peeling film can be peeled off after the hardening hot-melt silicone composition sheet is heated to form a hardened product. The timing of peeling the peeling film from the hardening silicone composition or the hardened product obtained therefrom can also be selected according to the purpose and use method of the hardening silicone composition sheet.

The curable silicone composition sheet has hot melt properties, so before the final curing, heating the sheet will soften it or even fluidize it, so that, for example, even if there are bumps or gaps on the bonded surface of the bonded body, the bumps or gaps can be filled without gaps to form a bonding surface with the bonded body. As a heating method for the curable hot melt silicone composition sheet, for example, various constant temperature baths, heating plates, electromagnetic heating devices, heating rollers, etc. can be used. In order to more efficiently bond the bonded body and the curable silicone composition sheet and heat the curable silicone composition, for example, it is preferable to use an electric heating press, a diaphragm type layer press, a roller type layer press, etc. [Method for forming a hardened material]

The present hardening hot-melt polysilicone composition can be hardened by a method comprising at least the following steps (I) to (III). (I)        A step of heating the present composition to above 100°C to melt it; (II)       A step of injecting the molten hardening hot-melt polysilicone composition obtained in the aforementioned step (I) into a mold, or a step of spreading the molten hardening hot-melt polysilicone composition obtained in the aforementioned step (I) throughout the mold by clamping the mold; and (III)       A step of hardening the hardening hot-melt polysilicone composition injected into the mold in the aforementioned step (II).

In the above steps, a transfer molding machine, a compression molding machine, an injection molding machine, an auxiliary plunger molding machine, a slider molding machine, a double plunger molding machine, or a low-pressure sealing molding machine can be used. In particular, for the purpose of obtaining a hardened product by transfer molding and compression molding, the composition of the present invention can be preferably used.

Finally, in step (III), the curable polysilicone composition injected (applied) into the mold in step (II) is cured. This step can be performed at a low temperature as described below, and is preferably performed in this manner.

The curable polysilicone composition of the present invention can be formed into a cured product in the following manner: by irradiating the composition of the present invention (or its semi-cured product) with high energy rays such as ultraviolet rays, the silicification catalyst as the component (D) is activated, thereby carrying out the silicification reaction of the composition. The types of high energy rays are as described above. The irradiation amount varies depending on the type of high energy ray-activated catalyst. In the case of ultraviolet rays, the cumulative irradiation amount at 365 nm is preferably in the range of 100 mJ/ ^cm2 to 100 J/ ^cm2 , and can also be in the range of 500 mJ/ ^cm2 to 50 J/ ^cm2 , and can also be in the range of 500 mJ/ ^cm2 to 20 J/ ^cm2 . That is, the curing reactive polysilicone composition of the present invention can start the curing reaction by irradiation with high energy rays such as ultraviolet rays. In addition, if the silane hydrogenation catalyst as component (D) is activated once, even if the irradiation with high energy rays is stopped, the curing reaction will proceed over time at room temperature or under heating to form a cured product.

The curing reaction does not require heating, so curing can be performed in a low temperature range (15°C to 100°C) including room temperature (25°C). In addition, in the embodiment of the present invention, "low temperature" refers to, for example, 100°C or less, specifically, a temperature range of 15°C to 100°C, and can also be selected as a temperature below 80°C. When the composition of the present invention (including semi-cured products) reacts in a temperature range of 15°C to 100°C, it is preferably placed near room temperature (a temperature range that can be reached without heating or cooling, especially including a temperature range of 20°C to 25°C), or cooled to below room temperature and above 15°C, or heated to above room temperature and below 100°C. In addition, the time required for the curing reaction can be appropriately designed according to the exposure amount and temperature of high-energy rays such as ultraviolet rays. In addition, according to the allowability and necessity of the process, temporary heating above 100°C can be performed, and the curing reaction can be performed simultaneously with the pressing by heating and pressing.

On the other hand, the curable hot-melt polysilicone composition of the present invention can be formed into a thin film sheet with a thickness ranging from 100 to 1000 µm by sandwiching between two peeling films and forming into a specified thickness by two rollers as described above. The thin film sheet formed by the curable hot-melt polysilicone composition can be used as a die bonding film used in the manufacture of semiconductor chips, etc., and a film-like curable polysilicone adhesive. [Use of the composition]

The curable hot-melt polysilicone composition of the present invention has hot-melt properties, excellent handling properties and curing properties when melted (hot-melted), and the cured product obtained by curing the composition has excellent coloration resistance at high temperatures, so it is usefully used in semiconductor components such as sealing materials for light-emitting/optical devices, light-reflecting materials, and optical semiconductors having the cured product. In addition, the mechanical properties of the cured product are excellent, so it is suitable as a sealant for semiconductors; a sealant for power semiconductors such as SiC and GaN; an adhesive, potting agent, protective agent, and coating agent for electrical and electronic applications. In addition, the curable hot-melt polysilicone composition of the present invention in the form of a sheet is suitable as a material for sealing or bonding large-area substrates using pressure molding, compression molding, or vacuum laminators. It is particularly suitable for use as a sealant for semiconductors using overmolding during molding. In addition, the composition in the form of a sheet can be used as a curable film adhesive or a stress buffer layer between two substrates with different linear expansion coefficients.

In addition, the curable hot-melt polysilicone composition of the present invention, especially the sheet-shaped curable hot-melt polysilicone composition, can be used for large-area sealing of semiconductor substrates (including wafers). In addition, the sheet formed by molding the curable hot-melt polysilicone composition of the present invention into a sheet can be used for die bonding films, sealing of flexible devices, stress relief layers for bonding two different substrates, etc. That is, the curable polysilicone composition of the present invention can be a sealant for the purpose of single-sided sealing, or a sealant for the purpose of double-sided sealing accompanied by bonding between two substrates, and has better properties suitable for such uses. [Uses of the cured product]

The use of the hardened material obtained by hardening the hardening polysilicone composition of the present invention is not particularly limited. The composition of the present invention has hot melt properties, is triggered by high energy line irradiation, and has excellent hardening properties even at low temperatures, excellent formability and mechanical physical properties, and the surface viscosity of the hardened material is low and relatively hard. Therefore, the hardened material obtained by hardening the composition can be suitably used as a component for semiconductor devices, and can be suitably used as a sealing material for semiconductor elements or IC (integrated circuit) chips, etc., and an adhesive and bonding component for semiconductor devices.

There is no particular limitation on the semiconductor device having a component containing a cured product obtained by curing the curable polysilicone composition of the present invention. In particular, the composition of the present invention forms an optically transparent cured product, and thus can be suitably used for applications requiring light to pass through. For example, preferably, it is a light-emitting semiconductor device as a light-emitting/optical device, an optical component for a display; a component for a solar panel; and especially a sealing material or bonding component used in such devices. In addition, the cured product of the present invention has excellent coloration resistance at high temperatures, and thus can be more suitably used as a sealing material or bonding component used in electronic materials where transparency, light resistance, and heat resistance are important. [Example]

The following is a detailed description of the curable polysilicone composition of the present invention and its production method using examples and comparative examples. In addition, in the following description, Me, Vi, and Ph in the average unit formula represent methyl, vinyl, and phenyl, respectively. Moreover, for the curable polysilicone composition of each example and comparative example, its softening point, curability, and storage stability were measured using the following method. The results are shown in Table 1. [Softening point]

The curable silicone composition is molded into cylindrical particles of φ14 mm×22 mm. The particles are placed on a heating plate set at 25℃ to 100℃, and a load of 100 grams is used to press from above for 10 seconds. After the load is removed, the deformation of the particles is measured. The temperature at which the deformation in the height direction becomes more than 1 mm is taken as the softening point. [Hardening characteristics]

According to the method specified in JIS K 6300-2:2001 "Unvulcanized rubber - Physical properties - Part 2: Method for determining vulcanization properties using a vibration vulcanizer", the curing properties were measured by vulcanizing the curable silicone composition for 600 seconds at the molding temperature (160°C) using a Curelastometer (PREMIER MDR manufactured by Alpha Technologies). In addition, the measurement was made by weighing a block of the curable hot-melt silicone composition of about 5g, sandwiching it between PET (polyethylene terephthalate) films with a thickness of 50 µm, and placing it on the lower mold. The time when the upper mold was closed was regarded as the start of the measurement. In addition, using an R-type mold for rubber, the amplitude angle was set to 0.53°, the vibration frequency was set to 100 times/minute, and the torque range was set to the maximum of 230 kgf･cm for measurement. The time required until the torque value exceeded 1 dNm (ts-1) was read in seconds as the measurement result. [Storage stability] The curable silicone composition was aged in an oven at 40°C for one week, and the curing characteristics were measured using the above method, and the ts-1 value was read.

Hereinafter, a mixture of an organopolysiloxane resin and a linear organopolysiloxane having a hot melt property was prepared by the method shown in Reference Examples 1 to 7, and its curability and storage stability at 100°C were evaluated. In addition, the low molecular weight organopolysiloxane component removed by the following method includes M ₄ Q structures, etc. [Reference Example 1]

The following components a1, a2 and b were dissolved in 4.00 kg of xylene in a drum using a three-one motor: 2.40 kg of an organic polysiloxane resin a1 which is a white solid at 25°C and represented by the average unit formula: (Me ₂ ViSiO _1/2 ) _0.05 (Me ₃ SiO _1/2 ) _0.39 (SiO _4/2 ) _0.56 (HO _1/2 ) _0.02 (vinyl content = 1.9 mass %); 4.46 kg of an organic polysiloxane resin a2 which is a white solid at 25°C and represented by the average unit formula: (Me ₃ SiO _1/2 ) _0.44 (SiO _4/2 ) _0.56 (HO _1/2 ) _0.02 (vinyl content = 0 mass %) kg; and dimethylpolysiloxane b (vinyl content = 0.09 mass %) with dimethylvinylsiloxy groups capping both ends of the molecular chain represented by the formula: ViMe ₂ SiO(Me ₂ SiO) ₈₀₀ SiViMe ₂ : 2.69 kg. The obtained solution was fed to a double-screw extruder with a maximum temperature setting of 230°C, and xylene and low molecular weight organic polysiloxane components were removed under a vacuum of -0.08 MPa, resulting in a hot-melt transparent mixture 1. The mixture 1 was received in a cylindrical barrel and directly cooled to solidify. The volatile content of the mixture was measured at 200°C × 1 hour, and the result was 0.7 mass %. [Reference Examples 2 to 7]

In addition to using the amounts of the organopolysiloxane resin a1, organopolysiloxane resin a2, dimethylpolysiloxane b having both ends of the molecular chain capped by dimethylvinylsiloxy groups, and xylene in Reference Example 1 as shown in Table 1 below, hot-melt transparent mixtures 2 to 7 were obtained in the same manner as Reference Example 1. The volatile content of the mixtures was measured at 200°C for 1 hour, and the result was 0.7% by mass. [Table 1] Reference Example No./ Amount of each ingredient used (kg) 1 2 3 4 5 6 7 Organic polysiloxane resin a1 (vinyl content = 1.9 mass %) 2.40 3.09 3.76 4.44 5.15 0.70 1.00 Organic polysiloxane resin a2 (vinyl content = 0 mass %) 4.46 3.77 3.08 2.39 1.72 6.30 6.00 Dimethylpolysiloxane b with dimethylvinylsiloxy end-capped at both ends of the molecular chain (vinyl content = 0.09 mass %) 2.69 2.69 2.50 2.49 2.37 2.85 2.53 Xylene 4.0 4.0 4.0 4.0 4.0 4.0 4.0 Mixture No. (volatile content = 0.7 mass %) 1 2 3 4 5 6 7 [Example 1]

The hot melt mixture 1 obtained in Reference Example 1 was fed from the production line 1 shown in FIG. 1 at 170° C. using a cylindrical barrel melter (VersaPail melter manufactured by Nordson Corporation) at a rate of 9.55 kg/hr into a twin-shaft extruder. Next, a mixture containing the following components is fed from the production line 3-a shown in FIG1: an organic hydrogenated polysiloxane represented by the formula: (PhSiO _3/2 ) _0.4 (HMe ₂ SiO _1/2 ) _0.6 (the volatile component amount when aged in an oven at 100°C under atmospheric pressure for 1 hour, i.e., the mass reduction rate is 3.4 mass %): 0.30 kg/hr; and methyltri-1,1-dimethyl-2-propynyloxysilane (boiling point = 245°C (1012.35 hPa)): 300 ppm relative to the entire composition. The set temperature of the input section is 150°C. Then, a mixture containing the following ingredients was fed from production line 3-b in FIG1 (the set temperature of the input part was 80°C): ViMe ₂ SiO(Me ₂ SiO) ₈₀₀ SiViMe ₂ , dimethylpolysiloxane b (vinyl content = 0.09 mass %) with both ends of the molecular chain terminated by dimethylvinylsiloxy groups: 0.15 kg/hr; and (methylcyclopentadienyl)trimethylplatinum (IV) (6.0 ppm in mass unit based on platinum metal relative to the entire composition); and the vacuum degree in the extruder was -0.08 MPa for deaeration and melt kneading. The outlet temperature of the double-screw extruder was set to 80°C, and the mixture was in the form of a semi-solid softened product. A peeling film (FL2-01 manufactured by TAKARAINC.CO.Ltd.) with a width of 330 mm and a thickness of 125 µm was conveyed at a speed of 1.0 m/min, and the mixture was supplied to the peeling film at a supply rate of 5 kg/hr. The mixture was inserted between two peeling films in a manner that the peeling surface of the peeling film was in contact with the mixture to form a laminate (the same applies to the following embodiments). Then, the laminate is pressurized between rollers controlled at 90°C to extend the mixture between the peeling films, thereby forming a laminate in which a 300 µm thick hardening hot-melt polysilicone composition sheet is inserted between two peeling films, and then the laminate is cooled by air cooling. The structure of the manufacturing device is shown in Figure 1. The peeling film is peeled off from the obtained laminate, thereby obtaining a bubble-free, flat, homogeneous, non-sticky and transparent hardening hot-melt polysilicone composition sheet with a softening temperature of 85°C. The obtained curable hot-melt silicone composite sheet was irradiated with ultraviolet light of a wavelength of 365 nm in such a manner that the irradiation amount became 10 J/cm ² , and the curability was measured at 100°C using the aforementioned method. The result was that its ts-1 was 59 seconds. The curable hot-melt silicone composite sheet was aged for one week in a 40°C oven and then irradiated with ultraviolet light as described above. The curability was measured again at 100°C, and the result was that its ts-1 was 61 seconds. The obtained curable hot-melt silicone composite sheet was irradiated with ultraviolet light as described above and heat-cured at 100°C for 1 hour using a hot press. A PET film was placed on the obtained cured product and a load of 0.5 kg/cm ² was applied, but no adhesion between the cured product and the PET film was observed. [Examples 2 to 7, Comparative Examples 1 to 4]

In the same manner as in Example 1, except that the type of the mixture, the organic hydrogenated polysiloxane, the curing retarder, the dimethyl polysiloxane b having both ends of the molecular chain capped by dimethylvinylsiloxy groups, the type of the silanization reaction catalyst, and the input amount (feed amount, concentration, etc.) were changed as shown in Table 2 (each example) and Table 3 (each comparative example), a bubble-free, flat, homogeneous, non-sticky and transparent curable hot-melt polysiloxane composition sheet and a peelable laminate containing the same were obtained. The softening temperature of the curable hot-melt polysilicone composition sheet of the embodiments, the curability (ts-1) immediately after manufacture and after aging (40°C for one week), and the adhesion of the cured product obtained by hot pressing after UV irradiation to the PET film were evaluated, and the results are shown in the table below.

[Table 2] Embodiment No. 1 2 3 4 5 6 7 Mixture No. 1 2 3 3 3 4 5 Feed rate of mixture (kg/hr) 9.55 9.56 9.34 9.33 9.33 9.32 9.24 The types of organic hydrogenated polysiloxane and their feed rates (kg/hr) are shown in the following formula: (PhSiO _3/2 ) _0.4 (HMe ₂ SiO _1/2 ) _0.6 (Mass reduction rate: 3.4 mass %) 0.30 0.45 0.530 0.610 (HMe ₂ SiO _1/2 ) _0.52 (Me ₂ SiO _2/2 ) _0.15 (SiO _4/2 ) _0.33 (Mass reduction rate: 2.9 mass %) 0.295 0.360 0.520 Type of hardening retarder and its concentration relative to the total composition Methyltri-1,1-dimethyl-2-propynyloxysilane (boiling point = 245°C (1012.35 hPa)) ppm 300 ppm 400 ppm 500 ppm 600 ppm 200 ppm 500 ppm 500 ppm Feed rate of dimethylpolysiloxane b (vinyl content = 0.09 mass %) with dimethylvinylsiloxy end-capped at both ends of the molecular chain (kg/hr) 0.15 0.15 0.21 0.31 0.15 0.15 0.15 (Methylcyclopentadienyl)trimethylplatinum(IV) (Concentration in ppm by mass as platinum metal relative to the total composition) 6.0 ppm 8.0 ppm 10.0 ppm 12.0 ppm 10.0 ppm 10.0 ppm 10.0 ppm Characteristics of hardening hot melt polysilicone composite sheet Softening temperature (℃) 85℃ 85℃ 80℃ 80℃ 80℃ 80℃ 75℃ Curing after UV irradiation at 100°C (just after manufacturing) ts-1 (seconds) 59 seconds 68 seconds 61 seconds 53 seconds 73 seconds 54 seconds 50 seconds Curing after UV irradiation at 100°C (40°C for one week) ts-1 (seconds) 61 seconds 66 seconds 60 seconds 54 seconds 71 seconds 54 seconds 50 seconds Adhesion to PET without without without without without without without [Table 3] Comparative example No. 1 2 3 4 Mixture No. 6 7 3 3 Feed rate of mixture (kg/hr) 9.85 9.53 9.34 9.40 The types of organic hydrogenated polysiloxane and their feed rates (kg/hr) are shown in the following formula: Me ₃ SiO(Me ₂ SiO) ₃₇ (MeHSiO) ₃₇ SiMe ₃ (mass reduction rate: 2.6 mass %) 0.120 0.068 HMe ₂ SiO(Me ₂ SiO) ₁₇ SiMe ₂ H (mass reduction rate: 8.3 mass %) 0.253 (PhSiO _3/2 ) _0.4 (HMe ₂ SiO _1/2 ) _0.6 (Mass reduction rate: 3.4 mass %) 0.45 0.45 Type of hardening retarder and its concentration relative to the total composition Methyltri-1,1-dimethyl-2-propynyloxysilane (boiling point = 245°C (1012.35 hPa)) ppm 200 ppm - 3500 ppm 1500 ppm Feed rate of dimethylpolysiloxane b (vinyl content = 0.09 mass %) with dimethylvinylsiloxy end-capped at both ends of the molecular chain (kg/hr) 0.15 0.15 0.21 0.21 (Methylcyclopentadienyl)trimethylplatinum(IV) (Concentration in ppm by mass as platinum metal relative to the total composition) 10.0 ppm 14.4 ppm - - Platinum complex in 1,3-divinyltetramethyldisiloxane solution (Concentration in ppm based on mass of platinum metal relative to the total composition) 4.0 ppm 4.0 ppm Characteristics of hardening hot melt polysilicone composite sheet Softening temperature (℃) 80℃ 85℃ 80℃ 80℃ Curing after UV irradiation at 100°C (just after manufacturing) ts-1 (seconds) 73 seconds 3 seconds -(**) 144 seconds Curing after UV irradiation at 100°C (40°C for one week) ts-1 (seconds) 80 seconds Unmelted -(**) 10 seconds Adhesion to PET have(*) have(*) without without (*) After placing a PET film on the obtained hardened product and applying a load of 0.5 kg/ ^cm2 , the hardened product can be seen to be adhered to the PET film. If it is peeled off, the hardened product will be torn. (**) No ts-1 was observed after 60 minutes. [Conclusion]

The curable polysiloxane composition of Examples 1 to 7 of the present invention uses a specific solid organic polysiloxane resin and a linear organic polysiloxane, and uses a photoactive siloxane hydrogenation catalyst, so that it can be cured at about 100°C by irradiation with ultraviolet light without losing storage stability. In addition, the surface viscosity of the obtained polysiloxane cured product is extremely low, so it is expected to be suitable for use in protecting semiconductor devices, etc.

On the other hand, although the hardened materials formed by the hardening polysilicon compositions of Comparative Examples 1 and 2 use a photoactive silane hydrocatalyst, the surfaces are highly viscous and sticky. If used for sealing semiconductor devices or in close contact with other substrates, the stickiness and adhesion due to the high viscosity are exhibited, and it is expected that there will be problems of inappropriate use. On the other hand, in Comparative Examples 3 and 4, which do not use the photoactive silane hydrocatalyst proposed by the present invention, it is impossible to provide a hardening polysilicon composition that has no loss of storage stability and can be thermally cured at a low temperature of about 100°C, and thus the problem of the present invention, namely, good hardening at low temperatures, cannot be achieved.

1: Hot melt machine 2: Extruder 3-a: Pump 3-b: Pump 3-c: Vacuum pump 4-a: Peeling sheet 4-b: Peeling sheet 5-a: Extension roller (optionally with temperature control function) 5-b: Extension roller (optionally with temperature control function) 6: Cooling roller 7: Film thickness gauge 8: Sheet cutting machine 9: Foreign matter inspection machine

[Fig. 1] is a schematic diagram of a double-shaft extruder used in the embodiment.

Claims (13)

A curable polysilicone composition, characterized in that it contains the following components and has heat-melting properties as a whole: (A) an organic polysiloxane resin containing the following components (A1) and (A2) in a mass ratio of 20:80 to 90:10: 100 parts by mass of (A1) an organic polysilicone resin having a functional group containing a carbon-carbon double bond in the molecule and having a siloxane unit represented by SiO _4/2 as at least 20 mol% of all siloxane units, which is not heat-melting alone and is solid at 25°C; (A2) an organic polysilicone resin having no functional group containing a carbon-carbon double bond in the molecule and having a siloxane unit represented by SiO 4/2 as at least 20 mol% of all siloxane units; (A) an organic polysiloxane resin in which the siloxane unit represented by _4/2 is at least 20 mol% of all siloxane units, which is not hot-melting alone and is solid at 25°C; (B) an organic polysiloxane having at least two curing reactive functional groups containing carbon-carbon double bonds in the molecule and which is liquid or plastic at 25°C in a linear or branched chain: 10 to 100 parts by weight; (C) an organic hydrogenated polysiloxane having at least two hydrogen atoms bonded to silicon in one molecule Siloxane (the number of hydrogen atoms bonded to silicon atoms is 0.5 to 20.0 per alkenyl group bonded to silicon atoms contained in the entire composition); (D) a catalyst for silanization reaction which is inactive without high energy ray irradiation but becomes active in the composition by irradiation with high energy ray: an amount sufficient to harden the composition and to reduce the mass reduction of the component (A) when exposed to 200°C for 1 hour to 2.0 mass % or less. The curable polysilicone composition of claim 1 further contains, as component (E), 1 to 5000 ppm of a curing retarder for silanization reaction having a boiling point of 200°C or above under atmospheric pressure, based on the total mass of the composition. The curable polysiloxane composition of claim 1 or 2, wherein the aforementioned component (A1) is an organic polysiloxane resin (A1-1) represented by the following average unit formula and which alone does not have a hot melt property: (R ¹ ₃ SiO _1/2 ) _a (R ¹ ₂ SiO _2/2 ) _b (R ¹ SiO _3/2 ) _c (SiO _4/2 ) _d (R ² O _1/2 ) _e (wherein each R ¹ is independently a monovalent hydrocarbon group having 1 to 10 carbon atoms, wherein 1 to 12 mol % of all R ¹ in a molecule are alkenyl groups; each R ² is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; a, b, c, d and e are numbers satisfying the following: 0.10≦a≦0.60, 0≦b≦0.70, 0≦c≦0.80, 0≦d≦0.65, 0≦e≦0.05, wherein c+d>0.20 and a+b+c+d=1); the aforementioned component (A2) is an organic polysiloxane resin (A2-1) represented by the following average unit formula and which alone does not have a hot melt property: (R ³ ₃ SiO _1/2 ) _f (R ³ ₂ SiO _2/2 ) _g (R ³ SiO _3/2 ) _h (SiO _4/2 ) _i (R ² O _1/2 ) _j (wherein each R ^{R 3} is independently a monovalent hydrocarbon group having 1 to 10 carbon atoms and not containing a carbon-carbon double bond; R ² is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; f, g, h, i and j are numbers satisfying the following: 0.35≦f≦0.55, 0≦g≦0.20, 0≦h≦0.20, 0.45≦i≦0.65, 0≦j≦0.05, and f+g+h+i=1); the aforementioned component (B) is (B1) a linear diorganopolysiloxane represented by the following structural formula: R ⁴ ₃ SiO(SiR ⁴ ₂ O) _k SiR ⁴ ₃ (wherein, each R ⁴ is independently a monovalent hydrocarbon group having 1 to 10 carbon atoms, wherein R ⁴ are alkenyl groups, and k is a number from 20 to 5,000). A curable polysilicone composition sheet or film, which is a sheet or film of a curable polysilicone composition of any one of claims 1 to 3, and is melt-kneaded in a temperature range of 50°C to 150°C and under vacuum, and then formed into a sheet or film shape. For example, the curable polysilicone composition sheet or film of claim 4 has a thickness between 10 and 1000 μm. A sheet or film adhesive comprising the curable polysilicone composition sheet or film of claim 4 or 5. A sheet or film sealant comprising the hardening polysilicone composition sheet or film of claim 4 or 5. A peelable laminate, comprising: a curable polysilicone composition sheet or film of claim 4 or 5; and a sheet-like or film-like substrate, which is attached to one or both sides of the curable polysilicone composition sheet or film and has a peelable surface opposite to the curable polysilicone composition sheet or film; and the curable polysilicone composition sheet or film can be peeled off from the sheet-like or film-like substrate having the peelable surface. A laminate comprising an electronic component or a substrate as a precursor thereof and a curable polysilicone composition layer, wherein the curable polysilicone composition layer is formed by making at least one side of the curable polysilicone composition sheet or film of claim 4 or 5 closely contact one part or all of the surface of the aforementioned substrate, and the aforementioned curable polysilicone composition is in an uncured state. A hardened product obtained by hardening the hardening polysilicone composition of any one of claims 1 to 3 by irradiating it with high energy rays. A method for manufacturing a laminate of claim 9, wherein at least one side of an uncured curable polysilicone composition sheet or film is brought into close contact with a portion or all of an electronic component or a substrate serving as a precursor thereof by one or more methods selected from vacuum lamination press, vacuum compression and compression molding. A method for manufacturing a laminate, wherein the laminate contains a cured polysilicon composition layer, the method comprising the following steps: irradiating the laminate of claim 9 with high energy rays and then curing the uncured curable polysilicon composition at room temperature or by heating. A method for manufacturing a laminate, wherein the laminate contains a cured polysilicon composition layer, the method comprising the following steps: after irradiating a curable polysilicon composition sheet or film of any one of claims 4 to 7 with high energy rays, at least one side of the uncured curable polysilicon composition sheet or film is brought into close contact with a part or all of an electronic component or a substrate serving as a precursor thereof by one or more methods selected from a vacuum laminating press, vacuum pressurization, and compression molding, and the polysilicon composition film or sheet is cured at room temperature or by heating to form a laminate.