Curable silicone gel composition, cured gel thereof, encapsulant, electronic article, and protection method for semiconductor chips

Abstract

[Problem] To provide a curable silicone gel composition for forming a silicone gel that has excellent thermal stability at high temperatures and vibration-damping properties that protect semiconductor chips from mechanical shock and vibration. [Solution] A curable silicone gel composition comprising: (A) an organopolysiloxane resin that has a mass loss of 2.0% by mass or less when component (A) is exposed to 200°C for 1 hour, and that does not have a hydrosilylation-reactive group; (B) a linear organopolysiloxane having alkenyl group terminals; (C) a linear organohydrogenpolysiloxane having SiH terminals; (D) a Q-branched organopolysiloxane having at least three silicon-bonded alkenyl groups on its molecular terminals; and (E) a hydrosilylation reaction catalyst.

Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application claims priority to and all benefits of U.S. Provisional Patent Application No. 63 / 391,137, filed July 21, 2022, the contents of which are incorporated herein by reference.

[0002] FIELD OF THE INVENTION The present invention generally relates to curable silicone gel compositions and silicone gels for use as encapsulants for electronic articles to seal or fill electrical or electronic components, and more particularly to curable silicone gel compositions capable of forming silicone gels that, compared to conventional known silicone gels, have superior thermal stability, capable of inhibiting the occurrence of cracks in the silicone gel caused by high temperatures or thermal shock exceeding 200°C for several hundred hours, and have excellent vibration-damping properties that protect semiconductor chips from mechanical shock and vibration resulting from a decrease in crosslink density in the cured silicone gel. [Background technology]

[0003] Silicone gels are known in the art and can protect electronic components from moisture, dirt, shock, vibration, and other harsh environmental factors, thereby extending their service life and reliability. As a result, silicone gels are often used to seal and protect electronic system assemblies, especially those with sensitive components. Silicone gels are commercially available as one- or two-part liquid formulations that are then dispensed and cured in place to form a networked elastomeric silicone gel. Hydrosilylation chemistry is typically the current reaction of choice for silicone gels, so curing can be achieved at room temperature or thermal acceleration can be utilized. Silicone gels combine the stress-relief properties of a fluid with the dimensional stability and minimal shrinkage of an elastomer in a solvent-free, by-product-free solution.

[0004] Silicone gel compositions are widely used to prepare silicone gels for use as sealants and fillers for electrical or electronic components.Considering the numerous conditions and industries in which such electrical or electronic components are used, it is increasingly desirable for silicone gels to have excellent thermal stability, including at temperatures of 200°C.However, traditional silicone gels are prone to cracking when exposed to such high temperatures for long periods of time, which is undesirable.

[0005] One attempt to improve the thermal stability of conventional silicone gels is to incorporate non-functional polydimethylsiloxanes, which reduce crosslink density. However, while the use of non-functional polydimethylsiloxanes can reduce the crosslink density of conventional silicone gels, their use also has an undesirable effect on other performance properties of conventional silicone gels, such as modulus. Another attempt has been to incorporate functional resins into silicone gel compositions, which become part of the crosslinked matrix of the silicone gel formed by curing. Although the use of functional resins provides desirable modulus, their use does not provide sufficient thermal stability and resistance to cracking at high temperatures. Summary of the Invention

[0006] 1. A curable silicone gel composition comprising: (A) an organopolysiloxane resin having a mass loss of 2.0% by weight or less when component (A) is exposed to 200° C. for 1 hour, and having a molecular weight of 1.0 or less; and a molecular weight of 1.0 or less; and a molecular weight of 1.0 or less; (R 1 3SiO 1 / 2 ) a (R 1 2SiO 2 / 2 ) b (R 1 SiO 3 / 2 ) c (SiO 4 / 2 ) d (R 2 O 1 / 2 ) e [In the formula, each R 1are independently monovalent hydrocarbon groups having 1 to 10 carbon atoms and no aliphatic unsaturation in the group, and each R 2 are independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and a, b, c, d, and e are numbers that satisfy the following: 0.10≦a≦0.60, 0.0≦b≦0.70, 0.0≦c≦0.80, 0.10≦d≦0.65, 0≦e≦0.05, and a+b+c+d=1. The composition comprises (B) a linear organopolysiloxane having two silicon-bonded alkenyl groups only at its molecular terminals and represented by the following formula: (R 3 R 1 2SiO 1 / 2 )(R 1 2SiO 2 / 2 ) n (R 3 R 1 2SiO 1 / 2 ) [In the formula, each R 1 are independently selected and defined above, and each R 3 are independently an alkenyl group having 2 to 10 carbon atoms, and the subscript n is a number from 10 to 1000. The composition additionally includes (C) a linear organohydrogenpolysiloxane having two silicon-bonded hydrogen atoms only at its molecular terminals and having a viscosity at 25°C of 2 to 10,000 mPa·s. Furthermore, the composition includes (D) a branched organopolysiloxane having at least three silicon-bonded alkenyl groups at its molecular terminals and having the following formula: (SiO 4 / 2 )[(R 1 2SiO 2 / 2 ) m (R 4 3SiO 1 / 2 )]4 [In the formula, each R 1 are independently selected and defined above, and each R 4 are independently 1 or an alkenyl group having 2 to 10 carbon atoms, provided that R 4wherein at least three of the m's are alkenyl groups, and each m' is independently a number from 5 to 200. Finally, the composition contains (E) a hydrosilylation reaction catalyst in an amount sufficient for the curing reaction between components (A) to (D).

[0007] An encapsulant for an electronic article comprising the curable silicone-based gel composition is also disclosed, along with a silicone-based gel prepared by curing the curable silicone-based gel composition.

[0008] Further provided is an electronic article comprising an encapsulant or silicone-based gel.

[0009] Finally, there is provided a method of protecting a semiconductor chip, comprising using a curable silicone-based gel composition, an encapsulant, or a silicone-based gel to protect the semiconductor chip. [Problem to be solved by the invention]

[0010] As electronic assembly units become increasingly more complex and power density requirements increase, the need for better vibration damping properties and thermal stability requirements of silicone gel materials increases.

[0011] While most conventional silicone gel materials can ensure reliable performance up to 150° C., there is an increasing demand in the industry for silicone gel materials that are stable at temperatures up to 200° C. Conventional silicone gel materials exhibit signs of failure under these conditions, including the formation of cracks or voids that can impair performance.

[0012] The vibration-damping properties of silicone gels provide a degree of protection against mechanical shock and vibration. The vibration-damping properties can be improved by reducing the crosslink density of the silicone gel. The incorporation of non-functional compounding ingredients, such as trimethylsiloxy-endblocked polydimethylsiloxane, is one of the technical approaches to reducing the crosslink density. However, these approaches generally involve compromises in other properties, such as the storage modulus (G'), which represents the stiffness of the material. Therefore, attempts to improve the vibration-damping properties have undesirably affected the storage modulus and other performance characteristics. [Means for solving the problem]

[0013] As a result of extensive investigation, the present inventors have found that the above-mentioned problems can be solved by a composition comprising, in combination: (A) an organopolysiloxane resin that has no hydrosilylation reactive groups and that has a mass loss of 2.0% by weight or less when exposed to 200°C for 1 hour; (B) a linear organopolysiloxane having two silicon-bonded alkenyl groups only on its molecular terminals; (C) a linear organohydrogenpolysiloxane that has two silicon-bonded hydrogen atoms only on its molecular terminals and has a viscosity at 25°C of 2 to 10,000 mPa s; (D) a Q-branched organopolysiloxane having at least three silicon-bonded alkenyl groups on its molecular terminals; and (E) a hydrosilylation reaction catalyst.

[0014] Effect of the invention The curable silicone gel composition of the present invention can be cured into a silicone gel that has excellent thermal stability at high temperatures and vibration-damping properties for protecting semiconductor chips from mechanical shock or vibration. Therefore, this curable silicone gel composition can be used as an encapsulant applied to electronic articles or as an encapsulant for electronic articles, and electronic articles having the encapsulant or silicone gel are provided. The present invention also provides a method for protecting semiconductor chips, which uses the curable silicone gel composition, the encapsulant applied to electronic articles, or the silicone gel. [Brief explanation of the drawings]

[0015] Various advantages and aspects of the present disclosure may be understood by consideration of the following detailed description when considered in conjunction with the accompanying drawings. [Figure 1] 1 shows the cured silicone gels of Examples 1-3 (designated by "INV1"-"INV3") both initially and after 744 hours of heat aging, with a crack-free condition. [Figure 2] 1 shows the cured silicone gels of Examples 4-7 (designated by "INV4"-"INV7") both initially and after 744 hours of heat aging, with a crack-free condition. [Figure 3] 1 shows the cured silicone gels of Comparative Examples 1-3 (denoted by "Comp1"-"Comp3") both initially (with cracked condition after aging) and after 744 hours of heat aging. DETAILED DESCRIPTION OF THE INVENTION

[0016] The present disclosure provides a curable silicone-based gel composition. The composition can be cured to provide a silicone-based gel with excellent physical properties, including thermal stability and vibration-damping properties. Therefore, the composition is particularly well-suited for use in or as an encapsulant for electronic components and electronic articles. However, the end use of the composition and the silicone-based gel formed therefrom is not so limited. Furthermore, the composition of the present invention is also characterized as having overall hot-melt properties. In this disclosure, unless otherwise specified, "having hot-melt properties" means having a softening point of 50 to 200°C, a melt viscosity at 150°C (preferably a melt viscosity of less than 1000 Pa·s), and flowability.

[0017] The composition of the present invention comprises (A) an organopolysiloxane resin having the following formula: (R 1 3SiO 1 / 2 ) a (R 1 2SiO2 / 2 ) b (R 1 SiO 3 / 2 ) c (SiO 4 / 2 ) d (R 2 O 1 / 2 ) e [In the formula, each R 1 are independently monovalent hydrocarbon groups having 1 to 10 carbon atoms and no aliphatic unsaturation in the group, and each R 2 are independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and a, b, c, d, and e are numbers that satisfy the following: 0.10≦a≦0.60, 0.0≦b≦0.70, 0.0≦c≦0.80, 0.10≦d≦0.65, 0≦e≦0.05, and a+b+c+d=1.

[0018] As will be understood by those skilled in the art, organopolysiloxane resins comprise inorganic silicon-oxygen-silicon groups (i.e., -Si-O-Si-) with organosilicon and / or organic side groups attached to the silicon atoms of the M, D, and T siloxy units. Organopolysiloxane resins are typically characterized in terms of the number, type, and / or proportion of [M], [D], [T], and / or [Q] units / siloxy groups, each of which represents a structural unit of an individual functional group present in the organopolysiloxane resin. Specifically, [M] is a group of the general formula R"SiO 1 / 2 [D] represents a monofunctional unit of the general formula R''2SiO 2 / 2 [T] represents a difunctional unit of the general formula R''SiO 3 / 2 and [Q] represents a trifunctional unit of the general formula SiO 4 / 2 and is represented by the following general structural moiety:

[0019] [ka]

[0020] In these general structural moieties, each R" is independently a monovalent or polyvalent substituent. As is understood in the art, the specific substituents suitable for each R" are not particularly limited (e.g., they can be monoatomic or polyatomic, organic or inorganic, linear or branched, substituted or unsubstituted, aromatic, aliphatic, saturated or unsaturated, etc., and various combinations thereof).

[0021] Those skilled in the art understand how the [M], [D], [T], and [Q] units and their relative proportions (i.e., mole fractions) influence and control the structure of a siloxane, and polysiloxanes can generally be monomeric, polymeric, oligomeric, linear, branched, cyclic, and / or resinous, depending on the selection of [M], [D], [T], and / or [Q] units therein. For example, [T] units and / or [Q] units are present in organopolysiloxane resins, but linear organopolysiloxanes typically do not contain such [T] units and / or [Q] units.

[0022] (A) In the organopolysilxoane resin, each R 1 are independently monovalent hydrocarbon groups having 1 to 10 carbon atoms and no aliphatic unsaturation in the group. 1 is not an alkenyl or alkynyl group. (A) Organopolysiloxanes generally do not contain hydrosilylatable functional groups (i.e., silicon-bonded ethylenically unsaturated groups and silicon-bonded hydrogen atoms). In general, R 1Suitable monovalent hydrocarbon groups can be independently linear, branched, cyclic, or a combination thereof. Cyclic hydrocarbyl groups include aryl groups and saturated or non-conjugated cyclic groups. Cyclic hydrocarbyl groups can be independently monocyclic or polycyclic. An example of a combination of linear and cyclic hydrocarbyl groups is an aralkyl group. General examples of monovalent hydrocarbon groups free of aliphatic unsaturation include alkyl groups, aryl groups, halocarbon groups, and the like, as well as derivatives, variants, and combinations thereof. Examples of suitable alkyl groups include methyl, ethyl, propyl (e.g., isopropyl and / or n-propyl), butyl (e.g., isobutyl, n-butyl, tert-butyl, and / or sec-butyl), pentyl (e.g., isopentyl, neopentyl, and / or tert-pentyl), hexyl, heptyl, octyl, and the like. Examples of suitable non-conjugated cyclic groups include cyclobutyl, cyclohexyl, and cycloheptyl groups. Examples of suitable aryl groups include phenyl, tolyl, xylyl, naphthyl, benzyl, and dimethylphenyl. Examples of suitable monovalent halogenated hydrocarbon groups (i.e., halocarbon groups) include halogenated alkyl groups, aryl groups, and combinations thereof. Examples of halogenated alkyl groups include the above-mentioned alkyl groups in which one or more hydrogen atoms have been replaced with halogen atoms such as F or Cl. Illustrative examples of halogenated alkyl groups include fluoromethyl, 2-fluoropropyl, 3,3,3-trifluoropropyl, 4,4,4-trifluorobutyl, 4,4,4,3,3-pentafluorobutyl, 5,5,5,4,4,3,3-heptafluoropentyl, 6,6,6,5,5,4,4,3,3-nonafluorohexyl, and 8,8,8,7,7-pentafluorooctyl, 2,2-difluorocyclopropyl, 2,3-difluorocyclobutyl, 3,4-difluorocyclohexyl, and 3,4-difluoro-5-methylcycloheptyl, chloromethyl, chloropropyl, 2-dichlorocyclopropyl, and 2,3-dichlorocyclopentyl groups, and derivatives thereof.Examples of halogenated aryl groups include the above-mentioned aryl groups in which one or more hydrogen atoms have been replaced with a halogen atom, such as F or Cl. Specific examples of halogenated aryl groups include chlorobenzyl and fluorobenzyl groups. In specific embodiments, each R. 1 is independently selected from alkyl groups having 1 to 10, alternatively 1 to 8, alternatively 1 to 6, alternatively 1 to 4, alternatively 1 to 2, alternatively 1 carbon atom.

[0023] (R 2 O 1 / 2 The moiety represented by (A) is typically inherently present when the (A) organopolysiloxane resin is prepared via silane hydrolysis and condensation. For example, the Q siloxy unit precursor may not be fully condensed when preparing the (A) organopolysiloxane resin, and thus, instead of four siloxane bonds, a Si—OR 2 This results in a siloxy unit containing the T moiety. (R 2 O 1 / 2 ) may not be present in the organopolysiloxane resin (A) depending on the preparation method.

[0024] As described above, the subscripted letters a, b, c, d, and e are numbers that satisfy 0.10 ≦ a ≦ 0.60, 0.0 ≦ b ≦ 0.70, 0.0 ≦ c ≦ 0.80, 0.10 ≦ d ≦ 0.65, 0 ≦ e ≦ 0.05, and a + b + c + d = 1. In specific embodiments, 0.10 ≦ a ≦ 0.60, alternatively 0.15 ≦ a ≦ 0.60, alternatively 0.20 ≦ a ≦ 0.60, alternatively 0.25 ≦ a ≦ 0.60, alternatively 0.30 ≦ a ≦ 0.60, alternatively 0.35 ≦ a ≦ 0.60, alternatively 0.40 ≦ a ≦ 0.60, alternatively 0.40 ≦ a ≦ 0.55. In these or other embodiments, 0.0 ≦ b ≦ 0.70, alternatively 0.0 ≦ b ≦ 0.60, alternatively 0.0 ≦ b ≦ 0.50, alternatively 0.0 ≦ b ≦ 0.40, alternatively 0.0 ≦ b ≦ 0.30, alternatively 0.0 ≦ b ≦ 0.20, alternatively 0.0 ≦ b ≦ 0.10, alternatively 0.0 ≦ b ≦ 0.05, alternatively 0.0 < b ≦ 0.05, alternatively b is 0. In these or other embodiments, 0.0 ≦ c ≦ 0.80, alternatively 0.0 ≦ c ≦ 0.70, alternatively 0.0 ≦ c ≦ 0.60, alternatively 0.0 ≦ c ≦ 0.50, alternatively 0.0 ≦ c ≦ 0.40, alternatively 0.0 ≦ c ≦ 0.30, alternatively 0.0 ≦ c ≦ 0.20, alternatively 0.0 ≦ c ≦ 0.10, alternatively 0.0 ≦ c ≦ 0.05, alternatively 0.0 < c ≦ 0.05, alternatively c is 0. In these or other embodiments, 0.10 ≦ d ≦ 0.65, alternatively 0.15 ≦ d ≦ 0.65, alternatively 0.20 ≦ d ≦ 0.65, alternatively 0.25 ≦ d ≦ 0.65, alternatively 0.30 ≦ d ≦ 0.65, alternatively 0.35 ≦ d ≦ 0.65, alternatively 0.40 ≦ d ≦ 0.60, alternatively 0.45 ≦ d ≦ 0.55. In these or other embodiments, 0.0 ≦ e ≦ 0.05, alternatively 0.0 < e ≦ 0.05, alternatively e is 0.

[0025] As will be understood in view of the description herein, in specific embodiments, (A) the organopolysiloxane resin may be classified as an MQ resin or otherwise may be referred to as an MQ resin, and as introduced above, M represents a monofunctional siloxy unit and Q represents a tetrafunctional siloxy unit (i.e., SiO 4 / 2) such MQ resins are known in the art as high molecular weight polymers composed primarily of M and Q units, and optionally a limited number of D and / or T units (e.g., a total of ≦20, alternatively ≦15, alternatively ≦10, alternatively ≦5 mol %), and typically exist in solid (e.g., powder or flake) form unless placed in a solvent. MQ resins are often represented by the general formula [M] x MQ resins are simply designated by [Q] (where the subscript x refers to the molar ratio of M siloxy units to Q siloxy units when the number of moles of Q siloxy units is normalized to 1). In such cases, the larger the value of x, the lower the crosslink density of the MQ resin. The converse is also true, as the value of x decreases, decreasing the number of M siloxy units and, therefore, allowing more Q siloxy units to be networked without terminating with M siloxy units. However, it will be understood that the normalized content of Q siloxy units does not imply or limit the MQ resin to only one Q unit. Rather, MQ resins typically include multiple Q siloxy units clustered or bonded together. In certain embodiments where the (A) organopolysiloxane resin is an MQ resin, x is from 0.5 to 1.5, alternatively from 0.6 to 1.4, alternatively from 0.7 to 1.3, alternatively from 0.8 to 1.2, or alternatively from 0.9 to 1.1.

[0026] In certain embodiments, (A) the organopolysiloxane has a weight-average molecular weight (M) of greater than 1,000 to 100,000, alternatively greater than 5,000 to 50,000, alternatively 10,000 to 30,000, alternatively 14,000 to 20,000 g / mol. w The weight average molecular weight can be readily determined using gel permeation chromatography (GPC) techniques based on polystyrene standards.

[0027] Component (A) has a mass loss of 2.0% by mass or less when exposed to 200°C for 1 hour. A mass loss rate of 2.0% by mass or less when component (A) is exposed to 200°C for 1 hour means that the amount of volatile components in component (A) is low. (A) organopolysiloxane resin contains specific branched siloxane units (SiO 4 / 2 ) or Q siloxy units, and the amount of volatile components in component (A) is very low. Specifically, the mass loss rate of component (A) is 2.0% by weight or less, alternatively 1.5% by weight or less, alternatively 1.0% by weight or less when exposed to 200°C for 1 hour. The mass loss is simply measured based on the mass of component (A) before exposing component (A) to a temperature of 200°C for 1 hour compared to the mass of component (A) after exposing component (A) to a temperature of 200°C for 1 hour. In other words, the mass loss is the total mass, if any, lost by component (A) after exposing component (A) to a temperature of 200°C for 1 hour. Typically, exposing conventional organopolysiloxane resins to high temperatures causes a loss of mass. There is no specific requirement to expose component (A) to a temperature of 200°C for 1 hour to determine the mass loss. Any heat source, such as an oven, may be utilized. Alternatively, ambient conditions can be utilized, e.g., component (A) can be exposed to air, atmospheric pressure, relative humidity, etc. while being heated. In a specific embodiment, ambient conditions other than temperature are not controlled when measuring the mass loss of component (A). The mass loss of component (A) is measured based on the orgnaopolysiloxane resin of component (A) in its undiluted form; i.e., any vehicle or solvent present in component (A) is removed before measuring or determining the mass loss, since volatilization of any vehicle or solvent is not expected to affect the mass loss of component (A). In a specific embodiment, the mass loss of component (A) is based solely on the silicon-based compounds that volatilize from component (A) upon exposure to a temperature of 200°C for 1 hour. A silicon-based compound is any compound containing a silicon atom.

[0028] For example, in the production process of conventional organopolysiloxane resins containing a large number of branched siloxane units, volatile low-molecular-weight components are generally generated as by-products from the condensation of silane compounds, and these by-products are physically mixed with the conventional organopolysiloxane resin. For example, the conventional organopolysiloxane resin often serves as a physical matrix containing the by-products. These by-products, particularly small molecules with few siloxy units, are considered volatile components. However, because these volatile components do not contribute to cure or crosslink density, they have the effect of significantly reducing the hardness of the cured product obtained from curing a composition containing such conventional organopolysiloxane resin. As a result, when the cured product is exposed to temperatures exceeding 150°C for a long period of time, the by-products contained in or with the conventional organopolysiloxane resin volatilize, resulting in a significant decrease in the hardness of the cured product. Furthermore, the network of the cured product is SiO 4 / 2 When the siloxane unit represented by the formula (I) is contained in a large amount, the cured product tends to be extremely brittle in terms of hardness, and as a result, embrittlement also occurs.

[0029] By incorporating an organopolysiloxane resin (A) into the composition, it is possible to provide a cured product that is resistant to increases in hardness and embrittlement, even when exposed to temperatures exceeding 150°C for extended periods of time. Therefore, if the mass loss of component (A) exceeds the upper limit when exposed to 200°C for one hour, the resulting cured product will tend to experience a rapid increase in hardness and embrittlement, especially at high temperatures. The lower limit for the mass loss rate of component (A) is typically 0.0% by weight or no volatile low-molecular-weight components. However, in practical use, it should be noted that a range of 0.1 to 2.0% by weight, 0.2 to 1.5% by weight, or 0.3 to 0.8% by weight can adequately suppress changes in hardness of the cured product. When the mass loss rate of component (A) is 0.0% by weight, component (A) consists essentially of an organopolysiloxane resin, or alternatively, it can consist of an organopolysiloxane resin.

[0030] The type of the volatile low-molecular-weight component is not particularly limited, but the organopolysiloxane resin of the present invention is preferably SiO 4 / 2 Since it contains many branched siloxane units (Q units) expressed as M4Q, the volatile siloxane component expressed as R3SiO 1 / 2 In the present invention, the aforementioned mass loss rate is typically achieved by removing volatile low-molecular-weight components or volatile siloxane components from the (A) organopolysiloxane resin to obtain component (A).

[0031] Component (A) can comprise a combination or two or more different organopolysiloxane resins that differ in at least one property such as structure, molecular weight, or number of monovalent groups bonded to silicon atoms.

[0032] In certain embodiments, component (A) may further comprise a vehicle for carrying, solubilizing, or partially solubilizing the organopolysiloxane resin. When utilized, the vehicle typically comprises an organic fluid, generally comprising organic oils containing volatile and / or semi-volatile hydrocarbons, esters, and / or ethers. Common examples of such organic fluids include C6-C8 16 Alkanes, C8-C 16 Isoalkanes (e.g., isodecane, isododecane, isohexadecane, etc.), C8 to C 16 Branched esters (e.g., isohexyl neopentanoate, isodecyl neopentanoate, etc.), as well as derivatives, modifications, and combinations thereof, are included. Additional examples of suitable organic fluids include aromatic hydrocarbons, aliphatic hydrocarbons, alcohols with more than three carbon atoms, aldehydes, ketones, amines, esters, ethers, glycols, glycol ethers, alkyl halides, aromatic halides, and combinations thereof. Hydrocarbons include isododecane, isohexadecane, Isopar L (C 11 ~C 13 ), Isopar H(C 11 ~C 12 ), hydrogenated polydecene. Ethers and esters include isodecyl neopentanoate, neopentyl glycol heptanoate, glycol distearate, dicaprylyl carbonate, diethylhexyl carbonate, propylene glycol n-butyl ether, ethyl-3 ethoxypropionate, propylene glycol methyl ether acetate, tridecyl neopentanoate, propylene glycol methyl ether acetate (PGMEA), propylene glycol methyl ether (PGME), octyldodecyl neopentanoate, diisobutyl adipate, diisopropyl adipate, propylene glycol dicaprylate / dicaprate, octyl ether, octyl palmitate, and combinations thereof.

[0033] In some embodiments, the vehicle comprises or is an organic solvent. Examples of organic solvents include alcohols such as methanol, ethanol, isopropanol, butanol, and n-propanol; ketones such as acetone, methyl ethyl ketone, or methyl isobutyl ketone; aromatic hydrocarbons such as benzene, toluene, and xylene; aliphatic hydrocarbons such as heptane, hexane, and octane; glycol ethers such as propylene glycol methyl ether, dipropylene glycol methyl ether, propylene glycol n-butyl ether, propylene glycol n-propyl ether, and ethylene glycol n-butyl ether; halogenated hydrocarbons such as dichloromethane, 1,1,1-trichloroethane, and methylene chloride; chloroform; dimethyl sulfoxide; dimethylformamide, acetonitrile; tetrahydrofuran, white spirit; mineral spirit; naphtha; n-methylpyrrolidone, and the like, and derivatives, modifications, and combinations thereof.

[0034] The amount of vehicle present in component (A) depends on various factors (e.g., the choice of organopolysiloxane resin, the cure conditions to which the composition is intended to be exposed, etc.) and can be readily determined by one of ordinary skill in the art. Generally, if present, component (A) comprises a vehicle in an amount of 1 to 50, alternatively 20 to 50, alternatively 30 to 40 weight percent, based on the total weight of component (A). Typically, however, component (A) does not comprise a vehicle, and the organopolysiloxane resin is utilized in the composition in undiluted or dry form. Alternatively, component (A) may initially comprise a vehicle, and the vehicle may be removed from component (A) and / or the composition during preparation of the composition prior to its final use.

[0035] The composition typically includes component (A) in an amount from 1 to 40, alternatively from 2 to 40, alternatively from 3 to 40, alternatively from 4 to 40, alternatively from 5 to 40, alternatively from 6 to 40, 3 to 30, alternatively from 4 to 30, alternatively from 5 to 30, alternatively from 6 to 30 weight percent, based on the total weight of the composition. These weight ranges are typically based only on the organopolysiloxane resin of component (A), and not on any vehicle that may be present in component (A).

[0036] The composition further comprises (B) a linear organopolysiloxane having two silicon-bonded alkenyl groups only on its molecular terminals. In other words, component (B) does not contain any silicon-bonded alkenyl groups at pendant positions, i.e., silicon-bonded alkenyl groups bonded to silicon atoms in D siloxy units. The linear organopolysiloxane has the following formula: (R 3 R 1 2SiO 1 / 2 )(R 1 2SiO 2 / 2 ) n (R 3 R 1 2SiO 1 / 2 ), [Wherein, each R 1 are independently selected and defined above, and each R 3 are independently an alkenyl group having 2 to 10 carbon atoms, and n is a number from 10 to 1000. As shown in the above formula, each terminal M unit of the linear organopolysiloxane of component (B) contains one alkenyl group, i.e., the linear organopolysiloxane has a total of two silicon-bonded alkenyl groups, not at each molecular terminal.

[0037] R 3In the context of the above, "alkenyl" refers to an acyclic, branched, or unbranched monovalent hydrocarbon group having one or more carbon-carbon double bonds. Specific examples include vinyl, allyl, and hexenyl groups. Examples of ethylenically unsaturated groups include CH2=CH-, CH2=CHCH2-, CH2=CH(CH2)4-, CH2=CH(CH2)6-, CH2=C(CH3)CH2-, HC=C(CH3)-, HC=C(CH3)-, HC=C(CH3)CH2-, HC=CHCH2CH2-, and HC=CHCH2CH2CH2-. Typically, the double bond or ethylenic unsaturation is present in each R 3 It is the end of.

[0038] In specific embodiments, each R 1 is independently selected from alkyl groups having 1 to 10, alternatively 1 to 8, alternatively 1 to 6, alternatively 1 to 4, alternatively 1 to 2, alternatively 1 carbon atom.

[0039] The subscript n defines the number of D siloxy units present in the linear organopolysiloxane of component (B), which may alternatively be referred to as the degree of polymerization of the linear organopolysiloxane. In certain embodiments, the subscript n is from 10 to 1000, alternatively from 50 to 750, alternatively from 100 to 500, alternatively from 150 to 450, alternatively from 200 to 400, or alternatively from 250 to 350.

[0040] The linear organopolysiloxane of component (B) can be exemplified by a dimethylpolysiloxane having both molecular terminals capped with dimethylvinylsiloxy groups, a methylphenylpolysiloxane having both molecular terminals capped with dimethylvinylsiloxy groups, and / or a copolymer of a methylphenylsiloxane and a dimethylsiloxane having both molecular chain terminals capped with dimethylvinylsiloxy groups.

[0041] Alternatively, as a specific example of the linear organopolysiloxane of component (B), the linear organopolysiloxane may have the average formula: Vi(CH3)2SiO[(CH3)2SiO] nSi(CH3)2Vi The organopolysiloxane may comprise or consist of an organopolysiloxane having the formula: where Vi represents vinyl and the subscript n is as defined above. With respect to this average formula, any methyl group may be replaced with a different monovalent hydrocarbon group, and any vinyl group may be replaced with any alkenyl group.

[0042] In a specific embodiment, the viscosity of component (B) at 25° C. is from 10 to 100,000 MPa·s, alternatively from 10 to 10,000 MPa·s, alternatively from 50 to 10,000 MPa·s. Viscosity can be measured at 25° C. via a Brookfield LV DV-E viscometer with a spindle appropriately selected for the viscosity of the substantially linear polyorganopolysiloxane, i.e., RV-1 to RV-7.

[0043] Component (B) may comprise a combination or two or more different linear organopolysiloxanes that differ in at least one property such as structure, molecular weight, degree of polymerization, viscosity, and the like.

[0044] The composition may typically include component (B) in an amount from 1 to 60, alternatively from 2 to 55, alternatively from 5 to 50, alternatively from 5 to 40, alternatively from 7.5 to 35 weight percent, based on the total weight of the composition.

[0045] The composition additionally contains (C) a linear organohydrogenpolysiloxane having two silicon-bonded hydrogen atoms only at its molecular terminals. In other words, component (C) does not contain any silicon-bonded hydrogen atoms at pendant positions, i.e., silicon-bonded hydrogen atoms bonded to silicon atoms in D siloxy units. The linear organohydrogenpolysiloxane having silicon-bonded hydrogen atoms only at its molecular terminals of component (C) acts as a crosslinker for the composition.

[0046] In a specific embodiment, the linear organohydrogenpolysiloxane has the average unit formula: (HR 1 2SiO 1 / 2 )(R1 2SiO 2 / 2 ) n’ (HR 1 2SiO 1 / 2 ) [In the formula, each R 1 are independently selected and defined above, and the subscript n' is selected to provide a viscosity of the linear organohydrogenpolysiloxane at 25°C of from 2 to 10,000 MPa·s, alternatively from 10 to 10,000 MPa·s. In specific embodiments, the subscript n' is from 1 to 500, alternatively from 1 to 200, alternatively from 1 to 150, alternatively from 1 to 100, alternatively from 1 to 50, alternatively from 5 to 40, alternatively from 10 to 30.

[0047] In another specific embodiment, the linear organohydrogenpolysiloxane has the average formula: H(CH3)2SiO[(CH3)2SiO] n’ Si(CH3)2H wherein n' is as defined above. Component (C) may comprise a combination or two or more different linear organohydrogenpolysiloxanes that differ in at least one property, such as structure, molecular weight, degree of polymerization, viscosity, etc.

[0048] The composition typically comprises component (C) in an amount of 1 to 40, alternatively 2 to 30, alternatively 5 to 25 weight percent, based on the total weight of the composition. Component (C) is typically present in an amount to provide a molar ratio of silicon-bonded hydrogen atoms in component (C) to silicon-bonded alkenyl groups in components (B) and (D) (described below) (moles of silicon-bonded hydrogen atoms in component (C) to the total moles of silicon-bonded alkenyl groups present in the other components of the composition) of 0.2:1 to 5:1, alternatively 0.8:1 to 1.2:1.

[0049] In addition, the composition includes (D) a Q-branched organopolysiloxane having at least three silicon-bonded alkenyl groups on its molecular terminals. "Q-branched" with respect to component (D) means that the branches in component (D) are Q-siloxy units, i.e., SiO 4 / 2The Q branched organopolysiloxane of component (D) is represented by the following formula: (SiO 4 / 2 )[(R 1 2SiO 2 / 2 ) m (R 4 3SiO 1 / 2 )]4 [In the formula, each R 1 are independently selected and defined above, and each R 4 are independently 1 or an alkenyl group having 2 to 10 carbon atoms, provided that R 4 At least three of R are alkenyl groups, and each subscript m is independently a number from 5 to 200. 1 A suitable example of 4 Illustrative examples of alkenyl groups for are described above.

[0050] Q branched organopolysiloxanes generally contain M siloxy units (i.e., (R 4 3SiO 1 / 2 )siloxy units), D siloxy units (i.e., (R 1 2SiO 2 / 2 ) siloxy units), and Q siloxy units (i.e., (SiO 4 / 2 Although the Q branched organopolysiloxane polymer contains one Q siloxy unit, those skilled in the art would consider the Q branched organopolysiloxane to be a branched silicone polymer, rather than a silicone resin, due to the degree of polymerization (DP) in the Q branched organopolysiloxane and the low mole fraction of Q siloxy units present therein.

[0051] Q branched organopolysiloxanes have a degree of polymerization (DP) of 20 to 800, alternatively 50 to 600, alternatively 100 to 400, alternatively 150 to 350, alternatively 175 to 325. As understood in the art, the DP of a Q branched organopolysiloxane is the sum or total of each m, which indicates the number of D siloxy units in each linear branch of the Q branched organopolysiloxane. Q branched organopolysiloxanes include Q units having four linear chains of D siloxy units capped with M siloxy units. Each linear chain has an independently selected subscript m, and thus the length or number of siloxy units in each linear chain is also independently selected. In certain embodiments, each subscript m is different. In other embodiments, each subscript m is the same.

[0052] The Q branched organopolysiloxane of component (D) may also have the following formula: Si-[[OSiR 1 2] m [OSiR 4 3]]4 [In the formula, each R 1 and R 4 are independently selected and defined above, and each subscript m is independently selected and defined above.

[0053] In specific embodiments, each R 1 is methyl (Me), and each R 4 is vinyl (Vi). In these embodiments, the Q branched organopolysiloxane of component (D) has the general formula: Si-[[OSiMe2] m [OSiMe2Vi]]4 wherein m is independently selected and defined above. However, as noted above, the M siloxy units and / or the D siloxy units can be different from one another.

[0054] Regardless of the selection of the Q branched organopolysiloxane of component (D), the Q branched organopolysiloxane must be R 4In certain embodiments, the Q branched organopolysiloxane has from greater than 0 to 7, alternatively from 0.1 to 6, weight percent R based on the total weight of the Q branched organopolysiloxane. 4 This typically means that each R 4 is vinyl, and each R 1 However, as is understood in the art, there are certain cases where R 1 is other than methyl (e.g., ethyl, aryl), and / or R 2 If R is other than vinyl (e.g., allyl, hexenyl), the total weight percentage will be smaller for the same number of alkenyl groups. 4 The content of is determined by silicon-29 nuclear magnetic resonance spectroscopy ( 29 Si NMR) can be used to determine and calculate the

[0055] Combinations of different Q-branched organopolysiloxanes may be utilized together as component (D).

[0056] In certain embodiments, the Q branched organopolysiloxane has a viscosity at 25°C of greater than 0 to less than 12,000, alternatively greater than 50 to 10,000, alternatively greater than 50 to 7,500, alternatively greater than 50 to 5,000, alternatively greater than 50 to 2,500, alternatively greater than 50 to less than 1,000 MPa·s.

[0057] The composition typically comprises component (D) in an amount from 20 to 90, alternatively from 30 to 80, alternatively from 40 to 75 weight percent, based on the total weight of the composition.

[0058] The composition further comprises (E) a hydrosilylation catalyst. The (E) hydrosilylation catalyst can be, without limitation, any known hydrosilylation catalyst for catalyzing a hydrosilylation reaction. A combination of different hydrosilylation catalysts may also be used.

[0059] The (E) hydrosilylation catalyst may be in or on a solid support. Examples of supports include activated carbon, silica, silica alumina, alumina, zeolites, and other inorganic powders / particles (e.g., sodium sulfate). The (E) hydrosilylation catalyst may also be placed in a vehicle, such as a solvent that solubilizes the (E) hydrosilylation catalyst, or alternatively, a vehicle that simply carries but does not solubilize the (E) hydrosilylation catalyst. Such vehicles are known in the art.

[0060] In specific embodiments, the (E) hydrosilylation catalyst comprises platinum. In these embodiments, the (E) hydrosilylation catalyst is exemplified by compounds such as platinum black, chloroplatinic acid, chloroplatinic acid hexahydrate, reaction products of chloroplatinic acid with monohydric alcohols, platinum bis(ethylacetoacetate), platinum bis(acetylacetonate), platinum chloride, and complexes of such compounds with olefins or organopolysiloxanes, as well as platinum compounds microencapsulated in matrices or core-shell compounds. Microencapsulated hydrosilylation catalysts and methods for their preparation are also known in the art, as exemplified by U.S. Pat. Nos. 4,766,176 and 5,017,654, which are incorporated herein by reference in their entireties.

[0061] Platinum complexes with organopolysiloxanes suitable for use as (E) hydrosilylation catalysts include 1,3-diethenyl-1,1,3,3-tetramethyldisiloxane platinum complexes. These complexes may be microencapsulated in a resin matrix. Alternatively, the (E) hydrosilylation catalyst may include 1,3-diethenyl-1,1,3,3-tetramethyldisiloxane platinum complexes. The (E) hydrosilylation catalyst may be prepared by a method comprising reacting chloroplatinic acid with an aliphatic unsaturated organosilicon compound, such as divinyltetramethyldisiloxane, or an alkene-platinum-silyl complex.

[0062] (E) The hydrosilylation catalyst may also, or instead, be a photoactivatable hydrosilylation catalyst, which may initiate curing via irradiation and / or heat. The photoactivatable hydrosilylation catalyst may be any hydrosilylation catalyst capable of catalyzing a hydrosilylation reaction, particularly upon exposure to radiation having a wavelength of 150 to 800 nanometers (nm).

[0063] Specific examples of photoactivatable hydrosilylation catalysts suitable for (E) hydrosilylation catalyst include platinum(II) bis(2,4-pentanedioate), platinum(II) bis(2,4-hexanedioate), platinum(II) bis(2,4-heptanedioate), platinum(II) bis(1-phenyl-1,3-butanedioate, platinum(II) bis(1,3-diphenyl-1,3-propanedioate), platinum(II) bis(1,1,1,5,5,5-hexafluoro-2,4-pent ... platinum(II) β-diketonate complexes such as platinum(II) β-diketonate complexes, (Cp)trimethylplatinum, (Cp)ethyldimethylplatinum, (Cp)triethylplatinum, (chloro-Cp)trimethylplatinum, and (trimethylsilyl-Cp)trimethylplatinum, where Cp represents cyclopentadienyl; triazene oxide-transition metal complexes, for example, [Pt[C6H5NNNOCH3]4, Pt[p-CN-C6H4NNNOCH6] 11 ]4, Pt[p-H3COC6H4NNNOC6H 11 ]4, Pt[p-CH3(CH2) x -C6H4NNNOCH3]4, 1,5-cyclooctadienePt[p-CN-C6H4NNNOC6H 11 ]2, 1,5-cyclooctadiene Pt[p-CH3O-C6H4NNNOCH3]2, [(C6H5)3P]3Rh[p-CN-C6H4NNNOC6H 11 ], and Pd[p-CH3(CH2) x —C6H4NNNOCH3]2 [wherein x is 1, 3, 5, 11, or 17]; η 4 -1,5-cyclooctadienyl)diphenylplatinum, η 4-1,3,5,7-cyclooctatetraenyl)diphenylplatinum, (η 4 -2,5-norborazienyl)diphenylplatinum, (η 4 -1,5-cyclooctadienyl)bis-(4-dimethylaminophenyl)platinum, (η 4 -1,5-cyclooctadienyl)bis-(4-acetylphenyl)platinum, and (η 4 Typically, the photoactivatable hydrosilylation catalyst is a Pt(II) β-diketonate complex, and more typically, the catalyst is platinum(II) bis(2,4-pentanediatoate).

[0064] (E) The hydrosilylation catalyst is present in the composition in a catalytic amount, i.e., an amount or quantity sufficient to promote cure under the desired conditions. The hydrosilylation catalyst can be a single hydrosilylation catalyst or a mixture comprising two or more different hydrosilylation catalysts.

[0065] The catalytic amount of (E) hydrosilylation catalyst can be >0.01 ppm to 10,000 ppm, alternatively >1,000 ppm to 5,000 ppm. Alternatively, a typical catalytic amount of (E) hydrosilylation catalyst is 0.1 ppm to 5,000 ppm, alternatively 1 ppm to 2,000 ppm, alternatively >1 ppm to 1,000 ppm. Alternatively, the catalytic amount of (E) hydrosilylation catalyst can be 0.01 ppm to 1,000 ppm, alternatively 0.01 ppm to 100 ppm, alternatively 20 ppm to 200 ppm, alternatively 0.01 ppm to 50 ppm of platinum group metal, based on the total weight of the composition.

[0066] In certain embodiments, the composition further comprises (F) an adhesion promoter. Suitable adhesion promoters may include hydrocarbon oxysilanes such as alkoxysilanes, combinations of alkoxysilanes with hydroxy-functional polyorganosiloxanes, amino-functional silanes, epoxy-functional silanes, mercapto-functional silanes, or combinations thereof. Adhesion promoters are known in the art and may be represented by the formula R 5 a R 6 b Si(OR 7 ) 4-(a+b) [In the formula, each R 5 are independently a monovalent organic group having at least 3 carbon atoms, and R 6 contains at least one SiC-bonding substituent having an adhesion-promoting group such as an amino group, an epoxy group, a mercapto group, or an acrylate group, and each R 7 are independently monovalent organic groups (e.g., methyl, ethyl, propyl, butyl, etc.), the subscript a has a value ranging from 0 to 2, the subscript b is either 1 or 2, and the sum of (a + b) is 3 or less. In certain embodiments, the (F) adhesion promoter comprises a partial condensate of the above silanes. In these or other embodiments, the (F) adhesion promoter comprises a combination of an alkoxysilane and a hydroxy-functional polyorganosiloxane.

[0067] In some embodiments, the (F) adhesion promoter comprises an unsaturated or epoxy-functional compound. In such embodiments, the (F) adhesion promoter comprises an unsaturated or epoxy-functional alkoxysilane, such as a silane of the formula: (XIII):R 8 c Si(OR 9 ) (4-c) wherein subscript c is 1, 2, or 3; alternatively, subscript c is 1. 8 are independently a monovalent organic group, provided that at least one R 8R is an unsaturated organic group or an epoxy-functional organic group. 8 Epoxy-functional organic groups of R are exemplified by 3-glycidoxypropyl and (epoxycyclohexyl)ethyl. 8 The unsaturated organic groups are exemplified by 3-methacryloyloxypropyl, 3-acryloyloxypropyl, and unsaturated monovalent hydrocarbon groups such as vinyl, allyl, hexenyl, undecylenyl, and the like. 9 are independently saturated hydrocarbon groups having 1 to 4 carbon atoms, alternatively 1 to 2 carbon atoms. 9 is exemplified by methyl, ethyl, propyl, and butyl.

[0068] Specific examples of suitable epoxy-functional alkoxysilanes include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, (epoxycyclohexyl)ethyldimethoxysilane, (epoxycyclohexyl)ethyldiethoxysilane, and combinations thereof. Examples of suitable unsaturated alkoxysilanes include vinyltrimethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, hexenyltrimethoxysilane, undecylenyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropyltriethoxysilane, 3-acryloyloxypropyltrimethoxysilane, 3-acryloyloxypropyltriethoxysilane, and combinations thereof.

[0069] In some embodiments, the (F) adhesion promoter comprises an epoxy-functional siloxane (such as any of those described above), such as the reaction product of a hydroxy-terminated polyorganosiloxane with an epoxy-functional alkoxysilane, or a physical blend of a hydroxy-terminated polyorganosiloxane with an epoxy-functional alkoxysilane. The (F) adhesion promoter may comprise a combination of an epoxy-functional alkoxysilane and an epoxy-functional siloxane. For example, the (F) adhesion promoter is exemplified by a mixture of 3-glycidoxypropyltrimethoxysilane with the reaction product of a hydroxy-terminated methylvinylsiloxane and 3-glycidoxypropyltrimethoxysilane, a mixture of 3-glycidoxypropyltrimethoxysilane with a hydroxy-terminated methylvinylsiloxane, or a mixture of 3-glycidoxypropyltrimethoxysilane with a hydroxy-terminated methylvinylsiloxane / dimethylsiloxane copolymer.

[0070] In certain embodiments, the (F) adhesion promoter is an amino-functional silane, such as H2N(CH2)2Si(OCH3)3, H2N(CH2)2Si(OCH2CH3)3, H2N(CH2)3Si(OCH3)3, H2N(CH2)3Si(OCH2CH3)3, CH3NH(CH2)3Si(OCH3)3, CH3NH(CH2)3Si(OCH2CH3)3, CH3NH(CH2)5Si(OCH3)3, CH3NH(CH2)5Si(OCH2CH3)3, H2N(C H2)2NH(CH2)3Si(OCH3)3, H2N(CH2)2NH(CH2)3Si(OCH2CH3)3, CH3NH(CH2)2NH(CH2)3Si(OCH3)3, CH3NH(CH2)2NH(CH2)3Si(OCH2 CH3)3, C4H9NH(CH2)2NH(CH2)3Si(OCH3)3, C4H9NH(CH2)2NH(CH2)3Si(OCH2CH3)3, H2N(CH2)2SiCH3(OCH3)2, H2N(CH2)2SiCH3(O CH2CH3)2, H2N(CH2)3SiCH3(OCH3)2, H2N(CH2)3SiCH3(OCH2CH3)2, CH3NH(CH2)3SiCH3(OCH3)2, CH3NH(CH2)3SiCH3(OCH2CH3)2 , CH3NH(CH2)5SiCH3(OCH3)2, CH3NH(CH2)5SiCH3(OCH2CH3)2, H2N(CH2)2NH(CH2)3SiCH3(OCH3)2, H2N(CH2)2NH(CH2)3SiCH3(OC H2CH3)2, CH3NH(CH2)2NH(CH2)3SiCH3(OCH3)2, CH3NH(CH2)2NH(CH2)3SiCH3(OCH2CH3)2, CH4H9NH(CH2)2NH(CH2)3SiCH3(OCH3)2, CH4H9NH(CH2)2NH(CH2)3SiCH3(OCH3)2, CH4H9NH(CH2)2NH(CH2)3SiCH3(OCH2CH3), N-(3-(trimethoxysilyl)propyl)ethylenediamine, and the like, and combinations thereof. In these or other embodiments, the (F) adhesion promoter comprises a mercapto-functional alkoxysilane, such as 3-mercaptopropyltrimethoxysilane or 3-mercaptopropyltriethoxysilane.

[0071] Additional examples of adhesion promoters include the reaction product of an epoxyalkylalkoxysilane, such as 3-glycidoxypropyltrimethoxysilane, with an amino-substituted alkoxysilane, such as 3-aminopropyltrimethoxysilane, and optionally with an alkylalkoxysilane, such as methyltrimethoxysilane.

[0072] An exemplary adhesion promoter includes a reaction mixture of an amino-containing organoalkoxysilane and an epoxy-containing organoalkoxysilane. Such a reaction mixture is disclosed in Japanese Patent Publication No. 52-8854(B) and Japanese Patent Application Laid-Open No. 10-195085(A).

[0073] The molar ratio of the alkoxysilane having an amino group-containing organic group to the alkoxysilane having an epoxy group-containing organic group is typically within the range of (1:1.5) to (1:5), alternatively within the range of (1:2) to (1:4). This component can be easily synthesized by mixing the alkoxysilane having an amino group-containing organic group and the alkoxysilane having an epoxy group-containing organic group, as mentioned above, and reacting them at room temperature or by heating.

[0074] Specifically, when an alkoxysilane having an amino group-containing organic group is reacted with an alkoxysilane having an epoxy group-containing organic group by the method described in JP-A-10-195085(A), the present invention is obtained by cyclization through an alcohol exchange reaction, and the compound represented by the general formula:

[0075] [ka] [In the formula, R 1 is an alkyl group, an alkenyl group, or an alkoxy group, and R 2 is of the general formula:

[0076] [ka] (In the formula, R 4 is an alkylene group or an alkyleneoxyalkylene group, and R 5 is a monovalent hydrocarbon group, and R 6 is an alkyl group and a is 0, 1 or 2, or

[0077] [ka] (In the formula, R 7 is an alkylene group, and R 8 is an alkyl group, an alkenyl group, or an acyl group, and R 3 are the same or different groups selected from the group consisting of groups represented by the formula: (wherein R, R, and R are the same or different hydrogen atoms or alkyl groups). Examples of carbasilatrane derivatives include carbasilatrane derivatives having a silicon-bonded alkoxy group or a silicon-bonded alkenyl group in each molecule represented by the following structure:

[0078] [ka] In the formula, Rc is a group selected from a methoxy group, an ethoxy group, a vinyl group, an allyl group, and a hexenyl group.

[0079] Furthermore, in the present invention, a silatrane derivative represented by the following structural formula may be used as an adhesion promoter:

[0080] [ka] In the formula, R 1 are the same or different hydrogen atoms or alkyl groups, and R 1 is typically a hydrogen atom or a methyl group. 2 is a hydrogen atom, an alkyl group, and a group of the general formula: -R 4 -Si(OR 5 )x R 6 (3-x) [In the formula, R 2 At least one of R is an organic group containing an alkoxysilyl group. 2 Examples of the alkyl group include a methyl group. 2 In the organic group containing an alkoxysilyl group, R 4 is a divalent organic group, examples of which include alkylene groups and alkyleneoxyalkylene groups. Typical examples include ethylene groups, propylene groups, butylene groups, methyleneoxypropylene groups, and methyleneoxypentylene groups. Furthermore, R 5 is an alkyl group having 1 to 10 carbon atoms, and is generally a methyl group or an ethyl group. 6 is a substituted or unsubstituted monovalent hydrocarbon group, typically a methyl group. Furthermore, x in the formula is 1, 2, or 3, typically 3.

[0081] R 2 Examples of such organic groups containing an alkoxysilyl group include the following groups: -(CH2)2Si(OCH3)3-(CH2)2Si(OCH3)2CH3 -(CH2)3Si(OC2H5)3-(CH2)3Si(OC2H5)(CH3)2 -CH2O(CH2)3Si(OCH3)3 -CH2O(CH2)3Si(OC2H5)3 -CH2O(CH2)3Si(OCH3)2CH3 -CH2O(CH2)3Si(OC2H5)2CH3 -CH2OCH2Si(OCH3)3-CH2OCH2Si(OCH3)(CH3)2

[0082] When utilized, (F) the adhesion promoter is present in the composition in an amount of greater than 0 to 3, alternatively 0.001 to 2.0 weight percent, based on the total weight of the composition.

[0083] In certain embodiments, the composition comprises (G)(g1) an alkali metal silanolate and (g2) M 1 Cl y Chloride salts represented by (R 5 COO) y M 1 [wherein each R 5 are the same or different monovalent hydrocarbon groups, M 1 is cerium or a rare earth metal mixture containing cerium as the main component, and y is M 1 The cerium content of the rare earth metal mixture is in the range of 1 to 3 depending on the valence of the rare earth metal. By "major component," it is meant that the rare earth metal mixture contains cerium in an amount greater than the amount of any other rare earth metal present in the mixture.

[0084] Component (G), when utilized, is used to enhance the heat resistance of the composition and the cured product formed therefrom. In a specific embodiment, component (G) contains 0.5 to 5.0 wt. % cerium (metal). The alkali metal silanolate (g1) is typically an alkali metal silanolate compound obtained by subjecting at least one cyclic organopolysiloxane to a ring-opening reaction using an alkali metal hydroxide, followed by further reaction of the resulting product with an organopolysiloxane having a viscosity in the range of 10 to 1,000,000 MPa·s at 25°C, alternatively 100 to 10,000 MPa·s. The cyclic organopolysiloxane is not particularly limited, but typically contains 3 to 8 siloxy units.Examples of cyclic organopolysiloxanes include hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), dodecamethylcyclohexasiloxane (D6), 1,1-diethylhexamethylcyclotetrasiloxane, phenylheptamethylcyclotetrasiloxane, 1,1-diphenylhexamethylcyclotetrasiloxane, 1,3,5,7-tetravinyltetramethylcyclotetrasiloxane, 1,3,5,7-tetramethylcyclotetrasiloxane, 1,3,5,7-tetracyclohexyltetramethylcyclotetrasiloxane, tris(3,3,3-trifluoropropyl)trimethylcyclotrisiloxane, 1,3,5,7-tetra(3-methacryloxypropyl)tetramethyl cyclotetrasiloxane, 1,3,5,7-tetra(3-acryloxypropyl)tetramethylcyclotetrasiloxane, 1,3,5,7-tetra(3-carboxypropyl)tetramethylcyclotetrasiloxane, 1,3,5,7-tetra(3-vinyloxypropyl)tetramethylcyclotetrasiloxane, 1,3,5,7-tetra(p-vinylphenyl)tetramethylcyclotetrasiloxane, 1,3,5,7-tetra[3-(p-vinylphenyl)propyl]tetramethylcyclotetrasiloxane, 1,3,5,7-tetra(N-acryloyl-N-methyl-3-aminopropyl)tetramethylcyclotetrasiloxane, 1,3,5,7-tetra(N,N-bis(lauroyl)-3-aminopropyl)tetramethylcyclotetrasiloxane, etc. Furthermore, mixtures of different cyclic organopolysiloxanes may also be used.

[0085] The alkali metal hydroxide is not particularly limited, and examples include sodium hydroxide, potassium hydroxide, etc. The amount of alkali metal hydroxide is typically 0.1 to 10.0 parts by mass per 100 parts by mass of the cyclic organopolysiloxane.

[0086] Any conventionally known organopolysiloxane having a viscosity at 25°C in the range of 100 to 1,000,000 MPa·s can be used as the organopolysiloxane that forms the alkali metal silanolate (g1). The organopolysiloxane is substantially liquid at room temperature and is a linear or branched organopolysiloxane having repeating diorganopolysiloxane units (linear chain structure) as the main component. The organic group (i.e., substituted or unsubstituted monovalent hydrocarbon group) bonded to the silicon atom can be the same organic group exemplified above. Examples of organopolysiloxanes include organopolysiloxanes having molecular ends blocked with triorganosiloxy groups, including trialkylsiloxy groups such as trimethylsiloxy groups, alkenyldialkylsiloxy groups such as vinyldimethylsiloxy groups, dialkenylalkylsiloxy groups such as divinylmethylsiloxy groups, and trialkenylsiloxy groups such as trivinylsiloxy groups, or organopolysiloxanes having molecular ends blocked with hydroxyl groups, alkoxy groups, or the like.

[0087] The salt of component (g2) is M 1 Cl y Chloride salts represented by (R 5 COO) y M 1 [wherein each R 5 are the same or different monovalent hydrocarbon groups, M 1 is cerium or a rare earth metal mixture containing cerium as the main component, and y is M 1 The range is 1 to 3 depending on the valence of M. 1 represents a mixture of rare earth elements containing cerium as the main component, and examples include cerium salts such as 2-ethylhexanoic acid, naphthenic acid, oleic acid, lauric acid, and stearic acid. Carboxylate salts can be used as organic solvent solutions. Examples of organic solvents include standard solvents, petroleum-based solvents such as mineral spirits, ligroin, and petroleum ether, as well as aromatic solvents such as toluene and xylene.

[0088] The amount of the salt of component (g2) is not particularly limited, but is typically 0.05 to 5 parts by mass, alternatively 0.1 to 3 parts by mass, of M per 100 parts by total mass of the above-mentioned component (g1). 1 Component (G) can be obtained by mixing component (g1) and component (g2) and then heat-treating the mixture at a temperature of 150°C or higher. The heating temperature for the heat treatment is typically 150 to 310°C, alternatively 200 to 305°C, alternatively 250 to 300°C.

[0089] When utilized, component (G) is present in the composition in an amount of greater than 0 to 3, 0.001 to 2.0 weight percent, based on the total weight of the composition.

[0090] The curable silicone composition of the present invention may further contain (H) a filler and / or (I) a pigment. The (H) filler may be, for example, but not limited to, a reinforcing filler, an extending filler, a thermally conductive filler, an electrically conductive filler, a flame-retardant filler, an acid-accepting filler, a rheology-modifying filler, a phosphor, a coloring filler, a mineral filler, a glass filler, a carbon filler, or a combination thereof. The selection of the (H) filler is typically a function of the cured product formed using the composition and the end-use application of the cured product.

[0091] The (H) filler may be untreated, pretreated, or added in combination with any filler treating agent described below, and when so added, the (H) filler may be treated in situ or prior to incorporation of the (H) filler into the composition. The (H) filler may be a single filler or a combination of two or more fillers that differ in at least one property, such as filler type, preparation method, treatment or surface chemistry, filler composition, filler shape, filler surface area, average particle size, and / or particle size distribution.

[0092] The shape and size of the (H) filler and / or (I) pigment are also not particularly limited. For example, the (H) filler can be spherical, oblong, oval, or irregular, and can be in the form of, for example, powder, dust, fiber, flake, chip, shavings, strand, scrim, wafer, wool, straw, particles, and combinations thereof. The size and shape are typically selected based on the type of (H) filler utilized, the selection of other ingredients included in the composition, and the end-use application of the cured product formed therefrom.

[0093] Non-limiting examples of fillers that can function as reinforcing fillers include reinforcing silica fillers such as fumed silica, silica aerogel, silica xerogel, and precipitated silica. Fumed silica is known in the art, for example, fumed silica is commercially available fumed silica sold under the name CAB-O-SIL by Cabot Corporation of Massachusetts, USA.

[0094] Non-limiting examples of fillers that may function as extending or reinforcing fillers include quartz and / or crushed quartz, aluminum oxide, magnesium oxide, silica (e.g., fumed silica, ground silica, precipitated silica), hydrated magnesium silicate, magnesium carbonate, dolomite, silicone resin, wollastonite, soapstone, kaolinite, kaolin, mica, muscovite, phlogopite, halloysite (hydrated alumina silicate), aluminum silicate, sodium aluminosilicate, glass (e.g., fibers, beads, or particles, including recycled glass from wind turbines or other sources), clay, magnetite, hematite, calcium carbonate, e.g., precipitated calcium carbonate, fumed calcium carbonate, and / or ground calcium carbonate, calcium sulfate, barium sulfate, calcium metasilicate, zinc oxide, talc, diatomaceous earth, iron oxide, clay, mica, chalk, titanium dioxide (titania), zirconia, sand, carbon black, graphite, anthracite, coal, lignite, charcoal, activated charcoal, non-functional silicone resins, alumina, silver, metal powders, magnesium oxide, magnesium hydroxide, magnesium oxysulfate fiber, aluminum trihydrate, oxyhydrate, coated fillers, carbon fiber (including, for example, recycled carbon fiber from the aircraft and / or automotive industries), polyaramids such as chopped KEVLAR™ or Twaron™, nylon fiber, mineral fillers or pigments (e.g., titanium dioxide, non-hydrated, partially hydrated, or hydrated fluorides, chlorides, bromides, iodides, chromates, carbonates, hydroxides, phosphates, hydrogen phosphates, nitrates, oxides, and sodium, potassium, magnesium, calcium, and barium; zinc oxide, antimony pentoxide, antimony trioxide, beryllium oxide, chromium oxide, lithopone, boric acid or borates, such as zinc borate, barium metaborate, or aluminum borate, mixed metal oxides, such as vermiculite, bentonite, pumice, perlite, fly ash, clay, and silica gel;Examples of suitable fillers include rice husk ash, ceramics and zeolites, metals such as aluminum flakes or powders, bronze powders, copper, gold, molybdenum, nickel, silver powders or flakes, stainless steel powders, tungsten, barium titanate, silica-carbon black composites, functionalized carbon nanotubes, cement, slate powders, pyrophyllite, sepiolite, zinc stannate, zinc sulfide, and combinations thereof. Alternatively, the extending or reinforcing filler may be selected from the group consisting of calcium carbonate, talc, and combinations thereof.

[0095] As known in the art, certain fillers can act as pigments. For example, white pigments can include metal oxides such as titanium oxide, aluminum oxide, zinc oxide, zirconium oxide, magnesium oxide, etc.; hollow fillers such as glass balloons and glass beads; and additionally barium sulfate, zinc sulfate, barium titanate, aluminum nitride, boron nitride, and antimony oxide. Such components can be considered as fillers and / or pigments.

[0096] Extending fillers are known in the art and are commercially available, such as crushed silica sold under the name MIN-U-SIL by US Silica (Berkeley Springs, WV). Suitable precipitated calcium carbonates include Solvay's Winnofil™ SPM, and SMI's Ultra-pflex™ and Ultra-pflex™ 100.

[0097] When the (H) filler includes a thermally conductive filler, the (H) filler may be both thermally conductive and electrically conductive. Alternatively, the (H) filler may be thermally conductive and electrically insulating. The thermally conductive filler may also have other beneficial properties, such as, but not limited to, reinforcing filler, extending filler, or another property as described above. The thermally conductive filler may be selected from the group consisting of, but not limited to, aluminum nitride, aluminum oxide, aluminum trihydrate, aluminum oxyhydrate, barium titanate, barium sulfate, beryllium oxide, carbon fiber, diamond, graphite, magnesium hydroxide, magnesium oxide, magnesium oxysulfate fiber, metal particles, onyx, silicon carbide, tungsten carbide, zinc oxide, coated fillers, and combinations thereof.

[0098] When the (H) filler includes a thermally conductive filler, the thermally conductive filler may include a metal filler, an inorganic filler, a meltable filler, or a combination thereof. Metal fillers include metal particles, metal powders, and metal particles having a layer on their surface. These layers may be, for example, a metal nitride layer or a metal oxide layer. Suitable metal fillers are exemplified by particles of a metal selected from the group consisting of aluminum, copper, gold, nickel, silver, and combinations thereof, alternatively aluminum. Suitable metal fillers are further exemplified by particles of the above-listed metals having a layer on their surface selected from the group consisting of aluminum nitride, aluminum oxide, copper oxide, nickel oxide, silver oxide, and combinations thereof. For example, the metal filler may include aluminum particles having an aluminum oxide layer on their surface. Inorganic fillers are exemplified by onyx; metal oxides such as aluminum trihydrate, aluminum oxyhydrate, aluminum oxide, beryllium oxide, magnesium oxide, and zinc oxide; nitrides such as aluminum nitride; carbides such as silicon carbide and tungsten carbide, and combinations thereof. Alternatively, inorganic fillers are exemplified by aluminum oxide, zinc oxide, and combinations thereof. The meltable filler may include Bi, Ga, In, Sn, or alloys thereof. Optionally, the meltable filler may further include Ag, Au, Cd, Cu, Pb, Sb, Zn, or combinations thereof. Examples of suitable meltable fillers include Ga, In-Bi-Sn alloy, Sn-In-Zn alloy, Sn-In-Ag alloy, Sn-Ag-Bi alloy, Sn-Bi-Cu-Ag alloy, Sn-Ag-Cu-Sb alloy, Sn-Ag-Cu alloy, Sn-Ag alloy, Sn-Ag-Cu-Zn alloy, and combinations thereof. The meltable filler may have a melting point between 50°C and 250°C. The meltable filler may be a eutectic alloy, a non-eutectic alloy, or a pure metal. Many suitable meltable fillers are commercially available.

[0099] Alternatively or in addition, (H) filler may comprise a non-reactive silicone resin other than component (A). For example, (H) filler may comprise a T resin, a TD resin, a TDM resin, a TDMQ resin, or any other non-reactive silicone resin. Typically, such non-reactive silicone resins contain at least 30 mole percent T siloxy and / or Q siloxy units. As is known in the art, D siloxy units are those that are not part of the R siloxy units. 0 2SiO 2 / 2 and the T siloxy unit is represented by R 0 SiO 3 / 2 where R 0 are independently selected substituents.

[0100] Weight average molecular weight of non-reactive silicone resin, M w M depends, at least in part, on the molecular weight of the silicone resin and the type of substituents (e.g., hydrocarbyl groups) present in the non-reactive silicone resin. w represents the weight average molecular weight measured using conventional gel permeation chromatography (GPC) with narrow molecular weight distribution polystyrene (PS) standard calibration when the peak representing the neopentamer is excluded from the measurement. The PS equivalent weight M of the non-reactive silicone resin w The viscosity of the non-reactive silicone resin may be 12,000 to 30,000 g / mol, typically 17,000 to 22,000 g / mol. The non-reactive silicone resin may be prepared by any suitable method. This type of silicone resin has been prepared by the hydrolysis of the corresponding silane or by the silica hydrosol capping method, both of which are commonly known in the art.

[0101] A phosphor is a type of filler that can convert the wavelength of light emitted from a light source (optical semiconductor device) when the cured product of the composition is used as a wavelength conversion material. There are no specific limitations on the phosphor, and examples of the phosphor include yellow light, red light, green light, and blue light phosphors. These phosphors include oxide phosphors, oxynitride phosphors, nitride phosphors, sulfide phosphors, and oxysulfide phosphors, which are widely used in light emitting diodes (LEDs).

[0102] In certain embodiments, the (H) filler may include an acid acceptor. The acid acceptor may include a metal oxide such as magnesium oxide. Acid acceptors are generally known in the art and are commercially available under trade names including Rhenofit F, Star Mag CX-50, Star Mag CX-150, BLP-3, and MaxOx98LR. Rhenofit F was calcium oxide manufactured by Rhein Chemie Corporation of Chardon, Ohio, USA. Star Mag CX-50 was magnesium oxide manufactured by Merrand International Corp. of Portsmouth, NH, USA. MagOX 98LR was magnesium oxide manufactured by Premier Chemicals LLC of W. Conshohocken, Pa., USA. BLP-3 was calcium carbonate manufactured by Omya Americas of Cincinnati, Ohio, USA.

[0103] Regardless of the selection of (H) filler, the (H) filler may be added to form the composition untreated, pretreated, or in combination with any filler treating agent, and when so added, the filler treating agent may treat the (H) filler in situ in the composition.

[0104] Filler treating agents may include silanes such as alkoxysilanes, alkoxy-functional oligosiloxanes, cyclic polyorganosiloxanes, hydroxyl-functional oligosiloxanes such as dimethylsiloxane or methylphenylsiloxane, organosilicon compounds, stearic acid, or fatty acids. The filler treating agent may include a single filler treating agent or a combination of two or more filler treating agents selected from similar or different types of molecules.

[0105] The filler treating agent may comprise an alkoxysilane, which may be a monoalkoxysilane, a di-alkoxysilane, a tri-alkoxysilane, or a tetraalkoxysilane. Examples of alkoxysilane filler treating agents include hexyltrimethoxysilane, octyltriethoxysilane, decyltrimethoxysilane, dodecyltrimethoxysilane, tetradecyltrimethoxysilane, phenyltrimethoxysilane, phenylethyltrimethoxysilane, octadecyltrimethoxysilane, octadecyltriethoxysilane, and combinations thereof. In certain embodiments, the alkoxysilane may be used in combination with a silazane, which catalyzes the reaction of the less reactive alkoxysilane with the surface hydroxyl. Such reactions are typically carried out at temperatures above 100°C, under high shear, and with the removal of volatile by-products such as ammonia, methanol, and water.

[0106] Suitable filler treating agents include alkoxysilyl-functional alkylmethylpolysiloxanes or similar materials in which the hydrolyzable groups can include, for example, silazane, acyloxy, or oximo.

[0107] Alkoxy-functional oligosiloxanes can also be used as filler treating agents. Alkoxy-functional oligosiloxanes and their preparation methods are generally known in the art. Other filler treating agents include mono-end-capped alkoxy-functional polydiorganosiloxanes, i.e., polyorganosiloxanes having an alkoxy functionality at one end.

[0108] Alternatively, filler treating agent can be any of the organosilicon compounds that are typically used to treat silica filler.The example of organosilicon compound includes organochlorosilane such as methyltrichlorosilane, dimethyldichlorosilane and trimethylmonochlorosilane; organosiloxane such as hydroxyl end-blocked dimethylsiloxane oligomer, silicon hydride functional siloxane, hexamethyldisiloxane and tetramethyldivinyldisiloxane; organosilazane such as hexamethyldisilazane and hexamethylcyclotrisilazane; and organoalkoxysilane such as alkylalkoxysilane with methyl, propyl, n-butyl, i-butyl, n-hexyl, n-octyl, i-octyl, n-decyl, dodecyl, tetradecyl, hexadecyl or octadecyl substituent. The organic reactive alkoxysilane may contain amino, methacryloxy, vinyl, glycidoxy, epoxycyclohexyl, isocyanurate, isocyanato, mercapto, sulfide, vinyl-benzyl-amino, benzyl-amino, or phenyl-amino substituents. Alternatively, the filler treating agent may include an organopolysiloxane. The use of such a filler treating agent to treat the surface of the (H) filler may utilize multiple hydrogen bonds, either clustered or dispersed, or both, as a method of bonding the organosiloxane to the surface of the (H) filler. The hydrogen-bondable organosiloxane has, on average, at least one silicon-bonded group capable of hydrogen bonding per molecule. The group may be selected from monovalent organic groups with multiple hydroxyl functionalities or monovalent organic groups with at least one amino functional group. Hydrogen bonding may be the primary form of bonding of the organosiloxane to the (H) filler. The organosiloxane may not be capable of forming covalent bonds with the (H) filler. The hydrogen-bonding capable organosiloxane may be selected from the group consisting of a saccharide-siloxane polymer, an amino-functional organosiloxane, and combinations thereof. Alternatively, the hydrogen-bonding capable polyorganosiloxane may be a saccharide-siloxane polymer.

[0109] Alternatively, the filler treating agent may include alkyl thiols such as octadecyl mercaptan, and fatty acids such as oleic acid, stearic acid, titanates, titanate coupling agents, zirconate coupling agents, and combinations thereof. One skilled in the art would be able to optimize the filler treating agent to aid in the dispersion of (H) the filler without undue experimentation.

[0110] If utilized, the relative amounts of filler treating agent and (H) filler are selected based on the particular filler utilized and filler treating agent and their desired effects or properties.

[0111] The amount of component (H) is not limited, but when utilized, the composition typically contains component (H) in an amount of 10 to 2,000 parts by weight, alternatively 10 to 1500 parts by weight, alternatively 10 to 1000 parts by weight, relative to the total (100 parts by weight) of components (A) to (D).

[0112] In certain embodiments, the composition further comprises an inhibitor, which can be used to modify the reaction rate or cure rate of the composition compared to a composition containing the same starting materials but omitting the inhibitor. Inhibitors include acetylenic alcohols such as methylbutynol, ethynylcyclohexanol, dimethylhexynol, and acetylenic alcohols such as 3,5-dimethyl-1-hexyn-3-ol, 1-butyn-3-ol, 1-propyn-3-ol, 2-methyl-3-butyn-2-ol, 3-methyl-1-butyn-3-ol, 3-methyl-1-pentyn-3-ol, 3-phenyl-1-butyn-3-ol, 4-ethyl-1-octyn-3-ol, and 1-ethynyl-1-cyclohexanol, and combinations thereof; 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetrahexenylcyclotetrasiloxane, and combinations thereof. Siloxanes and cycloalkenylsiloxanes such as methylvinylcyclosiloxanes, exemplified by their combinations; ene-yne compounds, such as 3-methyl-3-penten-1-yne, 3,5-dimethyl-3-hexen-1-yne; triazoles, such as benzotriazole; phosphines; mercaptans; hydrazines; amines, such as tetramethylethylenediamine; dialkyl fumarate, dialkenyl fumarate, dialkoxyalkyl fumarate, maleates, such as diallyl maleate; nitriles; ethers; carbon monoxide; alkenes, such as cyclooctadiene and divinyltetramethyldisiloxane; alcohols, such as benzyl alcohol; and combinations thereof. Alternatively, the inhibitor can be selected from the group consisting of acetylenic alcohols (e.g., 1-ethynyl-1-cyclohexanol) and maleates (e.g., diallyl maleate, bismaleate, or n-propyl maleate), and combinations of two or more thereof.

[0113] Alternatively, the inhibitor may be a silylated acetylenic compound. Without being bound by theory, it is believed that the addition of the silylated acetylenic compound reduces yellowing of the reaction product prepared from the hydrosilylation reaction of the composition when compared to the reaction product from the hydrosilylation of a composition that does not contain the silylated acetylenic compound or a composition that contains an organic acetylenic alcohol inhibitor such as those described above.

[0114] The silylated acetylene compounds are (3-methyl-1-butyn-3-oxy)trimethylsilane, ((1,1-dimethyl-2-propynyl)oxy)trimethylsilane, bis(3-methyl-1-butyn-3-oxy)dimethylsilane, bis(3-methyl-1-butyn-3-oxy)silanemethylvinylsilane, bis((1,1-dimethyl-2-propynyl)oxy)dimethylsilane, methyl(tris(1,1-dimethyl-2-propynyloxy))silane, methyl(tris(3-methyl-1-butyn-3-oxy))silane, (3-methyl-1-butyn-3-oxy)dimethylphenylsilane, (3-methyl-1-butyn-3-oxy)dimethylhexenylsilane, (3-methyl-1-butyn-3-oxy)triethylsilane, bis(3-methyl-1- cyclohexyl-1-ethyn-1-oxy)dimethylhexenylsilane, (cyclohexyl-1-ethyn-1-oxy)dimethylvinylsilane, (cyclohexyl-1-ethyn-1-oxy)diphenylmethylsilane, (cyclohexyl-1-ethyn-1-oxy)trimethylsilane, (cyclohexyl-1-ethyn-1-oxy)trifluoropropylsilane, (3,5-dimethyl-1-hexyn-3-oxy)trimethylsilane, (3-phenyl-1-butyn-3-oxy)diphenylmethylsilane, (3-phenyl-1-butyn-3-oxy)dimethylphenylsilane, (3-phenyl-1-butyn-3-oxy)dimethylvinylsilane, (3-phenyl-1-butyn-3-oxy)dimethylhexenylsilane, (cyclohexyl-1-ethyn-1-oxy)dimethylvinylsilane, (cyclohexyl-1-ethyn-1-oxy)diphenylmethylsilane, (cyclohexyl-1-ethyn-1-oxy)trimethylsilane, and combinations thereof. Alternatively, the inhibitor is exemplified by methyl(tris(1,1-dimethyl-2-propynyloxy))silane, ((1,1-dimethyl-2-propynyl)oxy)trimethylsilane, or a combination thereof. Silylated acetylenic compounds useful as inhibitors may be prepared by methods known in the art, for example, by silylation of the above-mentioned acetylenic alcohols by reaction with chlorosilanes in the presence of an acid acceptor.

[0115] The amount of inhibitor present in the composition will depend on various factors, including the desired pot life of the composition, whether the composition is a one-part or multi-part composition, the particular inhibitor used, and the selection and amounts of components (A)-(D). However, when present, the amount of inhibitor may be from 0% to 1%, alternatively from 0% to 5%, alternatively from 0.001% to 1%, alternatively from 0.01% to 0.5%, or alternatively from 0.0025% to 0.025%, based on the total weight of the composition.

[0116] The composition may further comprise (K) an organopolysiloxane or organosiloxane oligomer other than component (A), where the (K) organopolysiloxane or organosiloxane oligomer does not contain hydrosilylation-reactive functional groups. As is known in the art, hydrosilylation-reactive functional groups are silicon-bonded organic groups with aliphatic unsaturation (i.e., alkenyl and alkynyl groups) and silicon-bonded hydrogen atoms. When utilized, component (K) may be an oligomer, polymer, partially branched polymer, branched polymer, or three-dimensional network (i.e., resin). Component (K) may contain any combination of M, D, T, and Q siloxy units. When utilized, component (K), like component (A), does not participate in the hydrosilylation reaction that cures the composition to produce a cured product, i.e., a silicone gel.

[0117] In certain embodiments, the composition comprises an organopolysiloxane other than components (B) through (D) and having hydrosilylation reactive functional groups in an amount less than 10, alternatively less than 9.5, alternatively less than 9.0, alternatively less than 8.5, alternatively less than 8.0, alternatively less than 7.5, alternatively less than 7.0, alternatively less than 6.5, alternatively less than 6.0, alternatively less than 5.5, alternatively less than 5.0, alternatively less than 4.5, alternatively less than 4.0, alternatively less than 3.5, alternatively less than 3.0, alternatively less than 2.5, alternatively less than 2.0, alternatively less than 1.5, alternatively less than 1.0, alternatively less than 0.5, or alternatively 0 weight percent, based on the total weight of the composition.

[0118] In some embodiments, the composition further comprises a heat resistance improver other than component (G). The other resistance improver is exemplified by iron oxide (red iron oxide), cerium oxide, cerium dimethylsilanolate, a fatty acid cerium salt, cerium hydroxide, a zirconium compound, copper (Cu) phthalocyanine, or a combination thereof.

[0119] In some embodiments, the composition further comprises one or more additives. Examples of suitable additives that may be present in the composition include fillers, treatment agents (e.g., filler treatment agents), crosslinkers, adhesion promoters, surface modifiers, driers, extenders, biocides, flame retardants, plasticizers, end-capping agents, binders, anti-aging additives, water release agents, pigments, rheology modifiers, carriers, tackifiers, corrosion inhibitors, catalyst inhibitors, viscosity modifiers, UV absorbers, antioxidants, light stabilizers, and the like, and combinations thereof.

[0120] In certain embodiments, the composition and the silicone gel formed by curing the composition are substantially transparent.

[0121] The composition can be cured to give a cured product in the form of a silicone gel that has excellent physical properties, including resistance to cracking when exposed to high temperatures for extended periods of time. Because the generation of bubbles and cracks can be suppressed, the silicone gel has excellent bonding properties for electrical or electronic components.

[0122] The cured product or silicone gel typically has a Shore 000 hardness of from 10 to 100, alternatively from 50 to 90, alternatively from 70 to 90. Shore 000 durometer can be measured according to ASTM D2240.

[0123] Typically, the composition is cured by exposing it to an elevated temperature, which is not particularly limited, but is typically between 60° C. and 150° C., alternatively between 70° C. and 130° C. Alternatively, the composition can be cured under ambient conditions, such as room temperature, i.e., without exposing the composition to an elevated temperature.

[0124] Silicone gel has excellent heat resistance at temperatures above 180°C, and is less likely to deteriorate when used at high temperatures for long periods of time. Furthermore, when used to protect electronic components such as semiconductor chips, SiC semiconductor chips, ICs, hybrid ICs, and power devices, the silicone gel can suppress the formation of bubbles and cracks even under high temperature conditions. Furthermore, since it has good bonding properties to electrical or electronic components, the silicone gel has the advantage of being able to provide electrical or electronic components with high reliability and stability. Furthermore, since the silicone gel of the present invention is transparent, light-emitting semiconductor elements such as LEDs can be included in the semiconductor chips. Therefore, the silicone gel is particularly suitable for use as an encapsulant for electronic articles.

[0125] A method for sealing or filling an electrical or electronic component with a composition that forms an encapsulant for the electrical or electronic component includes, but is not limited to, contacting the portion of the electrical or electronic component to be protected with the composition, and then curing the composition by heating, leaving it at room temperature, or irradiating it with ultraviolet light, thereby obtaining an electrical or electronic component having an encapsulant that is a silicone gel formed from the composition.

[0126] The electrical or electronic components sealed, filled, or encapsulated with the silicone gel of the present invention are not limited, but the silicone gel of the present invention can suppress the generation of bubbles and cracks and exhibit good bonding to electrical or electronic components even under high-temperature conditions, making the silicone gel of the present invention advantageously usable in power devices used under high-temperature conditions, particularly power devices such as motor controls, transportation motor controls, power generation systems, and space transportation systems. Furthermore, the silicone gel of the present invention has a certain degree of cold resistance in addition to the heat resistance required for SiC semiconductor chips (e.g., heat resistance of 180°C or higher), making it advantageously usable in power devices that require the ability to withstand sudden temperature changes, thereby improving the durability and reliability of such power devices. Examples of power devices that require heat and cold resistance include motor control devices used in cold regions (e.g., general-purpose inverter control devices, servo motor control devices, machine tools or elevators, electric vehicles, hybrid cars, or motor control devices for rail transport used in cold regions), power generation systems used in cold regions (e.g., solar, wind, or fuel cell generators), and space transportation systems used in space. A "cold region" is a region where the temperature is below 0°C. Furthermore, the encapsulant for electrical or electronic components of the present invention is also effective for electrical or electronic components having narrow spaces between electrodes within the electrical or electronic component, between electrical elements, or between the electrical element and the package, or for electrical or electronic components having structures that cannot accommodate the expansion and contraction of the silicone gel. For example, it can be used in electrical circuits or modules in which electrical elements such as semiconductor elements, capacitors, and resistors are mounted, i.e., various sensors, such as pressure sensors generally sealed or filled with silicone gel, automotive ignition devices, regulators, etc. The electronic article may be an optoelectronic device, for example, mounted on a general lighting device, ad display article, optical article, or optoelectronic article.

[0127] Examples of such electrical or electronic components are the same as those mentioned above, in particular power devices such as motor controls, transport motor controls, power generation systems or space transportation systems.

[0128] The method for protecting semiconductor chips according to the present invention is a method for protecting semiconductor chips by using the silicone gel of the present invention, and an example of this method is a method for protecting semiconductor chips using the sealant for electrical or electronic components of the present invention as a sealant. Because this method for protecting semiconductor chips uses the silicone gel of the present invention, it is possible to provide electrical or electronic components, particularly power devices, that have high reliability and stability even under high-temperature conditions.

[0129] The following examples are intended to illustrate the present invention and should not be construed as limiting the scope of the invention in any way.

[0130] Certain ingredients utilized in the examples are set forth in Table 1 below.

[0131] [Table 1]

[0132] Preparation Example 1 A three-neck round-bottom flask was equipped with a stirring mechanism, nitrogen sweep, thermocouple, and water-cooled condenser. An organopolysiloxane resin linear mixture was prepared by combining 50.6 parts by weight of organopolysiloxane resin (A1) and 49.4 parts by weight of linear organopolysiloxane (B1) in the flask. The organopolysiloxane resin linear mixture was heated to 80°C and blended until a homogeneous mixture was formed. The homogeneous mixture was cooled to room temperature and then transferred to the addition funnel of a wipe film evaporator. The wipe film evaporator jacket was heated to 150°C and a vacuum of <1 mmHg was applied. The wipe film evaporator rotor blades were then activated, gradually feeding the homogeneous mixture into the wipe film evaporator via metered addition. Volatiles were then discarded and nonvolatiles were collected. The collected nonvolatiles are referred to as the MQ blend. The MQ blend contains less than 2 wt. % volatiles, specifically less than 0.3 wt. % QM4 neopentamer, as confirmed via GC analysis.

[0133] General Procedure 1: Examples 1-5 The compositions for Examples 1-5 were prepared according to General Procedure 1. In General Procedure 1, a dynamic axial centrifuge (DAC mixer) and a compatible plastic container were prepared. The following intermediates were added to the plastic container in the specified amounts (shown in the table below): MQ blend, Q-branched organopolysiloxane (D1), and linear organohydrogenpolysiloxane (C1). The intermediates were then mixed in the DAC mixer at 2,000 revolutions per minute (RPM) for 30 seconds. The walls of the plastic container were then scraped to remove the intermediates from the walls. The mixing process was repeated until a homogeneous blend was achieved. The hydrosilylation reaction catalyst (E1) was then added to the plastic container and mixed with the other intermediates in the DAC mixer at 2,000 RPM for 30 seconds. The mixing process was repeated until a homogeneous blend was achieved, resulting in a curable silicone gel composition.

[0134] General Procedure 2: Examples 6-7 The compositions for Examples 6-7 were prepared according to General Procedure 2. In General Procedure 2, a dynamic axial centrifuge (DAC mixer) and a compatible plastic container were prepared. The following intermediates were added to the plastic container in the specified amounts (shown in the table below): MQ blend, Q-branched organopolysiloxane (D1), and linear organohydrogenpolysiloxane (C1). The intermediates were then mixed in the DAC mixer at 2,000 RPM for 30 seconds. The walls of the plastic container were then scraped to remove the intermediates from the walls. The mixing process was repeated until a homogeneous blend was achieved. The adhesion promoter (F1), heat stabilizer (G1), and hydrosilylation catalyst (E1) were then added to the plastic container and mixed with the other intermediates in the DAC mixer at 2,000 RPM for 30 seconds. The mixing process was repeated until a homogeneous blend was achieved, resulting in a curable silicone gel composition.

[0135] [Table 2]

[0136] [Table 3]

[0137] General Procedure 3: Comparative Examples 1-4 The compositions for Comparative Examples 1-4 were prepared according to General Procedure 3. In General Procedure 3, a dynamic axial centrifuge (DAC mixer) and a compatible plastic container were prepared. The following intermediates were charged into the plastic container in the specified amounts (shown in Table 4 below): optionally, comparative siloxane (X1), optionally, comparative siloxane (X2), optionally, MQ blend, Q-branched organopolysiloxane (D1), and linear organohydrogenpolysiloxane (C1). The intermediates were then mixed in the DAC mixer at 2,000 RPM for 30 seconds. The walls of the plastic container were then scraped to remove the intermediates from the walls. The mixing process was repeated until a homogeneous blend was achieved. The hydrosilylation reaction catalyst (E1) was then added to the plastic container and mixed with the other intermediates in the DAC mixer at 2,000 RPM for 30 seconds. The mixing process was repeated until a homogeneous blend was achieved to obtain a comparative curable silicone gel composition.

[0138] [Table 4]

[0139] The compositions of Examples 1-7 and Comparative Examples 1-4 were cured to yield cured silicone gels that were analyzed as described below.

[0140] Cure and Thermal Stability Tests The compositions of Examples 1-7 and Comparative Examples 1-4 were mixed on a DAC mixer at 500 RPM for 30 seconds to remove any air bubbles. For each composition, a 20 g aliquot was carefully poured into a clean, dry Pyrex™ Petri dish, and seven 10 g aliquots were carefully poured into clean Al dishes. Each composition was allowed to cure for 48 hours under ambient conditions (22°C and 48% relative humidity) on a horizontal surface to yield a hardened gel.

[0141] Initial (T0) observations were collected on the cured gels. Shore 000 durometer was measured according to ASTM D2240, and the cured gels were inspected for clarity and the presence of any cracks, bubbles, or other defects. Cured gel samples in Al dishes were placed in a convection oven at 150°C, and cured gel samples in Pyrex™ Petri dishes were placed on a hot plate with a surface temperature of 200°C. The samples were monitored periodically throughout the course of the study: they were tested for Shore 000 durometer and observed for cracks, bubbles, and other defects. Photographs were taken using a camera and are shown in Figures 1-3, which show the cured gels of Examples 1-7 and Comparative Examples 1-3 both initially and after 744 hours of thermal aging. The thermal stability study was conducted over a period of 744 hours (31 days).

[0142] Rheological Test Methods Rheological data were obtained using an Anton Paar MCR-302 rheometer. Gel curing and rheological testing were performed at 25°C using 25mm parallel plates. The cured gel was mixed at 500 rpm for 30 seconds on a DAC mixer to remove air bubbles. An aliquot was then placed on the rheometer. The curing of the gel formulation was confirmed by monitoring the viscoelastic properties. After the gel formulation cured, the viscoelastic properties did not show any significant changes. A viscoelastic data set was then obtained at 1 Hz by applying strain within the linear viscoelastic region.

[0143] The thermal stability test results, summarized in Tables 5-7 below, demonstrate the superior thermal stability of Examples 1-7 over Comparative Examples 1-3. Unlike the cured gels of Examples 1-7, the cured gels of Comparative Examples 1-3 failed the thermal stability test, exhibiting crack formation at 744 hours, when the comparative siloxane (X1) was replaced with an MQ blend, as in Comparative Example 1; when the organopolysiloxane resin (A2) was omitted, as in Comparative Example 2; or when the organopolysiloxane resin (A2) loading was insufficient, at 3 wt.%, as in Comparative Example 3. In Tables 5-7 below, TO indicates gel quality at the time of formation (i.e., time 0), and T744h indicates gel quality after aging on a hot plate at 200°C for 744 hours.

[0144] The rheological property, tan delta, was used to evaluate damping properties. Tan delta represents the ratio of a material's viscous to elastic response (G" / G'), or the material's energy dissipation capacity. The higher the tan delta value, the better the damping properties. The rheological properties are summarized in Tables 5-7 below. The addition of organopolysiloxane resin (A2) systematically increased damping properties. As shown in Comparative Example 3 and Examples 1-5, the tan delta value increased from 0.10 to 0.19 as the organopolysiloxane resin (A2) content increased from 3 wt% to 20 wt%. Comparative Example 4 had 25 wt% of the comparative siloxane (X2) as the non-functional compounding component, while Example 5 had an equivalent content (20 wt%) of a non-functional MQ resin (i.e., organopolysiloxane resin (A2)). Despite the equivalent addition of non-functional compounding ingredients, the tan delta value of Example 5 was higher than that of Comparative Example 4 without any significant compromise in G'.

[0145] [Table 5]

[0146] [Table 6]

[0147]

Table 7

Claims

1. 1. A curable silicone gel composition comprising: (A) an organopolysiloxane resin having a mass loss of 2.0% by weight or less when component (A) is exposed to 200° C. for 1 hour, and having a molecular weight of 1.0 or less, the molecular weight of which is represented by the following formula: (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 [In the formula, each R １ are independently monovalent hydrocarbon groups having 1 to 10 carbon atoms and no aliphatic unsaturation in the group, and each R ２ are independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and a, b, c, d, and e are numbers that satisfy the following: 0.10≦a≦0.60, 0.0≦b≦0.70, 0.0≦c≦0.80, 0.10≦d≦0.65, 0≦e≦0.05, and a+b+c+d=1; and (B) a linear organopolysiloxane having two silicon-bonded alkenyl groups only on the ends of the molecule and having the following formula: (R ３ R １ ２ SiO １／２ )(R １ ２ SiO ２／２ ) ｎ (R ３ R １ ２ SiO １／２ ) [In the formula, each R １ are independently selected and defined above, and each R ３ are independently an alkenyl group having from 2 to 10 carbon atoms, and the subscript n is a number from 10 to 1000; (C) a linear organohydrogenpolysiloxane having two silicon-bonded hydrogen atoms only at its molecular terminals and having a viscosity at 25°C of 2 to 10,000 MPa s; (D) Q A branched organopolysiloxane having at least three silicon-bonded alkenyl groups on its molecular terminals and having the following formula: (SiO ４／２ )[(R １ ２ SiO ２／２ ) ｍ (R ４ ３ SiO １／２ )] ４ [In the formula, each R １ are independently selected and defined above, and each R ４ are independently R １ or an alkenyl group having 2 to 10 carbon atoms, provided that R ４ wherein at least three of the subscripts m are alkenyl groups, and each subscript m is independently a number from 5 to 200; and (E) a hydrosilylation reaction catalyst in an amount sufficient for the curing reaction between components (A) to (D).

2. the amount of component (A) is in the range of 5 to 25% by weight; the amount of component (B) is in the range of 5 to 50% by weight; the amount of component (C) is in the range of 5 to 25% by weight; the amount of component (D) is in the range of 30 to 80% by weight; 2. The curable silicone gel composition according to claim 1, wherein the amount of component (E) is in the range of 0.001 to 1.0% by mass, calculated as platinum group metal, when the total mass of components (A) to (E) in the composition is 100% by mass.

3. (F) an adhesion promoter, or (G) (g1) an alkali metal silanolate and (g2) M １ Cl ｙ or a chloride salt represented by (R ５ COO) ｙ M １ [wherein each R ５ are the same or different monovalent hydrocarbon groups, M １ is cerium or a rare earth metal mixture containing cerium as the main component, and y is M １ and at least one salt selected from the group consisting of:

3. The curable silicone gel composition according to claim 1, wherein the amount of component (F) or component (G) is 0.001 to 2.0% by mass, relative to the total mass of components (A) to (E) in the composition, taken as 100% by mass.

4. (H) an inorganic filler optionally treated with at least one surface treatment agent and / or optionally combined with other ingredients; (I) a pigment, or 4. The curable silicone gel composition according to claim 1, further comprising at least one selected from the group consisting of: (J) an organopolysiloxane or organosiloxane oligomer different from component (A), wherein the organopolysiloxane or organosiloxane oligomer of component (K) does not contain a hydrosilylation-reactive functional group containing aliphatic unsaturation in the molecule.

5. The curable silicone gel composition according to any one of claims 1 to 4, wherein the content of organopolysiloxanes having hydrosilylation reactive functional groups other than components (B) to (D) is 0.0 to 10.0% by mass, relative to the total mass of components (A) to (E) in the composition, taken as 100% by mass.

6. An encapsulant for an electronic article comprising the curable silicone-based gel composition of any one of claims 1 to 5.

7. 10. The encapsulant for an electronic article of claim 6, which is substantially transparent.

8. A silicone-based gel prepared by curing the curable silicone-based gel composition according to any one of claims 1 to 5, wherein the silicone-based gel has a Shore 000 hardness in the range of 10 to 100.

9. 9. The silicone-based gel of claim 8, which is substantially transparent.

10. 10. An electronic article comprising the encapsulant of claim 6 or 7 or the silicone-based gel of claim 8 or 9.

11. The electronic article of claim 10 mounted on a power device.

12. The electronic article of claim 10, wherein the electronic article is an optoelectronic device.

13. 13. The electronic article of claim 12 mounted on a general lighting device, a display article, an optical article, or an optoelectronic article.

14. A protection method for semiconductor chips, comprising using the curable silicone gel composition according to any one of claims 1 to 5, the encapsulant according to claim 6 or 7, or the silicone gel according to claim 8 or 9.

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