A platinum-phosphite complex-containing hydrosilylation catalyst, a method for producing the platinum-phosphite complex-containing hydrosilylation catalyst, and a curable organopolysiloxane composition containing the catalyst.

Abstract

To provide a platinum-phosphite complex-containing hydrosilylation catalyst that does not contain an organic solvent and that is liquid at 23°C.SOLUTION: The present invention pertains to: a platinum-phosphite complex-containing hydrosilylation catalyst that is liquid at 23°C and that is characterized by not containing a hydrocarbon-based organic solvent and by being obtained through the association of a platinum-phosphite ester complex and a silane compound and / or a partial hydrolysate thereof; and a method for producing the platinum-phosphite complex-containing hydrosilylation catalyst.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a platinum-phosphite complex-containing hydrosilylation catalyst, a curable organopolysiloxane composition using the catalyst, and a method for producing the platinum-phosphite complex-containing hydrosilylation catalyst. [Background technology]

[0002] The addition-curing type organopolysiloxane composition contains an organohydrogenpolysiloxane having a hydrogen atom (i.e., a hydrosilyl group) bonded to a silicon atom, an organopolysiloxane having an alkenyl group such as a vinyl group bonded to a silicon atom, and a platinum-based catalyst.

[0003] In the case of so-called one-component organopolysiloxane compositions, which combine these three components into a single composition, exposure to high-temperature conditions can lead to problems such as changes in properties like thickening and gelation, and changes in the physical properties of the cured organopolysiloxane product after curing. To avoid these problems, methods such as dividing the components into two or more parts and mixing them immediately before use to create a mixed-type organopolysiloxane composition, or transporting one-component organopolysiloxane compositions under refrigeration or freezing, are employed.

[0004] In the former case, there is a concern that the physical properties of the resulting organopolysiloxane cured product may change due to variations in formulation and mixing, requiring highly advanced formulation and mixing technologies. In the latter case, refrigeration or freezing conditions are required from storage to use, resulting in very high transportation and storage costs, making it commercially unfavorable. Against this backdrop, there has been a growing demand in recent years for one-component organopolysiloxane compositions that maintain their properties and performance even when stored for long periods at room temperature (here referring to 25°C).

[0005] In Patent Documents 1 and 2, methods for enhancing storage stability using certain specific phosphite ester compounds have been proposed. Although these methods significantly improve storage stability, they have problems such as being unable to obtain a sufficiently cured organopolysiloxane cured product without exposure to a high temperature of about 150°C, the phosphite ester compound being easily hydrolyzed and having poor storage stability in air, and the catalyst recrystallizing when the coordination number of the phosphite ester compound increases. Therefore, there has been a demand for a platinum-phosphite ester complex-containing hydrosilylation catalyst that is liquid at 23°C and does not contain an organic solvent. If such a catalyst can be obtained, a curable organopolysiloxane composition with stable properties and without an organic solvent can be obtained. Thus, the demand for a platinum-phosphite ester complex-containing hydrosilylation catalyst that is liquid at 23°C and does not contain an organic solvent has been increasing.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0007] The present invention has been made to solve such problems. By obtaining a platinum-phosphite ester complex-containing hydrosilylation catalyst that is liquid at 23°C without containing an organic solvent, the property stability of the catalyst itself is improved, and by using this catalyst in a curable organopolysiloxane composition, a curable silicone composition without an organic solvent can be obtained. Another object is to provide an organopolysiloxane composition in which the properties and physical properties are stable even when exposed to a temperature exceeding room temperature for a long time.

Means for Solving the Problems

[0008] The present invention has conducted intensive studies to achieve the above object, and provides a hydrosilylation catalyst containing a platinum-phosphite complex formed by the association of a platinum-phosphite complex and a silane compound and / or its partial hydrolyzate.

[0009] That is, the present invention provides a hydrosilylation catalyst containing a platinum-phosphite complex, which is an aggregate of the following component (A) and the following component (B), does not contain an organic solvent, and is liquid at 23°C. (A) A platinum-phosphite complex composed of platinum and a phosphite compound represented by the following general formula (1),

Chemical formula

Chemical formula

[0010] It is preferable that the component (B) is an alkoxysilane derivative in which the R 2 is a vinyl group.

[0011] The platinum-phosphite complex-containing hydrosilylation catalyst obtained by associating a complex of a phosphite compound represented by formula (1) with platinum and a silane compound represented by formula (2) and / or its partial hydrolysate can be kept liquid at room temperature, which offers advantages such as good workability and ease of uniform dispersion when the catalyst is incorporated into a curable organopolysiloxane composition.

[0012] The present invention can provide a curable organopolysiloxane composition that does not contain organic solvents and contains the above-mentioned platinum-phosphite complex-containing hydrosilylation catalyst.

[0013] Such a curable organopolysiloxane composition remains stable in terms of properties and physical characteristics even when exposed to temperatures above room temperature for extended periods, and an article having a cured product of the composition can be provided.

[0014] Furthermore, the present invention provides a method for producing the above-mentioned composition of a platinum-phosphite ester complex-containing hydrosilylation catalyst. In other words, the present invention provides a method for producing a platinum-phosphite complex-containing hydrosilylation catalyst comprising the following steps (a) to (d). (a) A step of preparing a solution by dissolving a phosphite ester compound represented by the following general formula (1) in a hydrocarbon solvent having a boiling point of 80°C or lower, [ka] (In the formula, R 1 (It is a monovalent aliphatic hydrocarbon group having 1 to 3 hydrogen atoms or carbon atoms.) (b) A step of adding an organic solvent-free platinum compound, selected from the group consisting of platinum chloride, chloroplatinic acid, or a complex of a chloroplatinate and a vinyl group-containing siloxane, to the solution and dispersing it to prepare a solution containing a platinum-phosphite complex. (c) Add a silane compound represented by the following general formula (2) and / or a partial hydrolyzate thereof to the solution obtained in (a) to (b) above, disperse them, and prepare a solution containing at least a part of the platinum-phosphite complex and an aggregate of the silane compound represented by the following general formula (2) and / or a partial hydrolyzate thereof. [Chemical formula] (In the formula, R 2 represents an alkenyl group having 2 to 10 carbon atoms, and R 3 is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms. Also, X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms or OR 3 .) (d) A step of removing the hydrocarbon solvent from the solution obtained in the step (c). [[ID=I7]]

[0015] By performing the steps (a) to (d), a platinum-phosphite complex-containing hydrosilylation catalyst can be stably produced.

[0016] In the step (c), the molar number of the alkenyl group in the silane compound represented by the general formula (2) and / or a partial hydrolyzate thereof added with respect to one platinum atom in the platinum compound is preferably within the range of 0.01 to 500 times. If it is 0.01 times or more, the liquid state can be maintained at 23 ° C, and no problems such as deterioration of dispersibility and reduction of compounding workability occur in the curable organopolysiloxane composition containing the catalyst due to the precipitation of crystals. Also, if it is 500 times or less, the addition amount of the silane compound represented by the general formula (2) and / or a partial hydrolyzate thereof is not too much, the molecular weight of the siloxane compound itself becomes appropriate, the influence on the viscosity of the obtained platinum-phosphite complex-containing hydrosilylation catalyst is also not a problem, the property stability of the obtained platinum-phosphite complex-containing hydrosilylation catalyst is good, and the workability when blending the catalyst is also good. [Effect of the Invention]

[0017] The platinum-phosphite ester complex-containing hydrosilylation catalyst of the present invention is liquid at 23°C even without the presence of organic solvents, thus exhibiting excellent property stability of the catalyst itself. Furthermore, when this catalyst is incorporated into a curable silicone composition, it can be easily and uniformly dispersed, allowing for the production of a curable organopolysiloxane composition free of organic solvents. The resulting organic solvent-free curable organopolysiloxane composition provides an organopolysiloxane composition with stable properties and physical characteristics even when exposed to temperatures above room temperature for extended periods. Moreover, because it does not contain organic solvents, it is possible to obtain a very safe organopolysiloxane cured product. [Modes for carrying out the invention]

[0018] The inventors of the present invention have explored catalysts useful as curing catalysts for resins, particularly for organopolysiloxane compositions, and have found that aggregates of platinum and platinum-phosphite ester complexes consisting of the following general formula (1), and silane compounds represented by the following general formula (2) and / or their partial hydrolysates are useful. Based on this, the inventors have completed the present invention, including a method for producing such catalysts.

[0019] In other words, the present invention is (A) Platinum and the following general formula (1) [ka] (In the formula, R 1 (It is a monovalent aliphatic hydrocarbon group having 1 to 3 hydrogen atoms or carbon atoms.) A platinum-phosphorite ester complex composed of a phosphite ester compound represented by, and (B) Silane compounds represented by the following general formula (2) and / or partial hydrolysates thereof, A hydrosilylation catalyst containing a platinum-phosphite ester complex, [ka] (In the formula, R 2R represents an alkenyl group with 2 to 10 carbon atoms. 3 X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms. Also, X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms or OR 3 (That is the case.) The hydrosilylation catalyst is the ( The present invention relates to a platinum-phosphite complex-containing hydrosilylation catalyst characterized by being an aggregate of component A and component B, not containing an organic solvent, and being liquid at 23°C.

[0020] Furthermore, the present invention is This is a method for producing a platinum-phosphite complex-containing hydrosilylation catalyst, characterized by comprising the following steps (a) to (d). (a) A step of preparing a solution by dissolving a phosphite ester compound represented by the following general formula (1) in a hydrocarbon solvent having a boiling point of 80°C or lower, [ka] (In the formula, R 1 (It is a monovalent aliphatic hydrocarbon group having 1 to 3 hydrogen atoms or carbon atoms.) (b) A step of adding an organic solvent-free platinum compound, selected from the group consisting of platinum chloride, chloroplatinic acid, or a complex of a chloroplatinate and a vinyl group-containing siloxane, to the solution and dispersing it to prepare a solution containing a platinum-phosphite complex. (c) A step of adding a silane compound represented by the following general formula (2) and / or a partial hydrolysate thereof to the solution obtained in steps (a) to (b) above and dispersing it to prepare a solution containing at least a portion of the platinum-phosphite ester complex and an aggregate of the silane compound represented by the following general formula (2) and / or a partial hydrolysate thereof. [ka] (In the formula, R 2 R represents an alkenyl group with 2 to 10 carbon atoms. 3X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms. Also, X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms or OR 3 (That is the case.) (d) A step of removing the hydrocarbon solvent from the solution obtained in step (c).

[0021] [Phosphite compounds] The phosphite ester compound represented by the following general formula (1) used in the present invention is an essential component for significantly improving the storage stability of the properties and physical characteristics of the curable organopolysiloxane composition containing the platinum-phosphite ester complex-containing hydrosilylation catalyst obtained using this compound, by forming a complex with platinum. [ka] (In the formula, R 1 (It is a monovalent aliphatic hydrocarbon group having 1 to 3 hydrogen atoms or carbon atoms.)

[0022] In the above general formula (1), R 1 R is independently a hydrogen atom or a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms, preferably having 1 to 2 carbon atoms, more preferably having 1 carbon atom, i.e., a methyl group. Specific examples of phosphite ester compounds include tris(2,4-dimethylphenyl) phosphite, tris(2,4-di-tert-butylphenyl) phosphite, tris(2,4-bis(3-ethylpentan-3-yl)phenyl) phosphite, tris(2,4-bis(4-propylheptan-4-yl)phenyl) phosphite, etc. 1 Phosphite ester compounds with the same number of carbon atoms, as well as R such as tris(4-(tert-butyl)-2-methylphenyl) phosphite, tris(4-(tert-butyl)-2-ethylphenyl) phosphite, tris(2-(tert-butyl)-4-(3-ethylpentan-3-yl)phenyl) phosphite, tris(2-(tert-butyl)-4-(3-methylhexane-3-yl)phenyl) phosphite, etc. 1Examples include phosphite ester compounds with different numbers of carbon atoms. Among these, tris(2,4-di-tert-butylphenyl)phosphite is particularly preferred because it is readily available and has high storage stability.

[0023] The optimal amount of phosphite ester compound used in this invention is between 0.6 and 3.0 molecules per molecule of platinum, and more preferably between 0.8 and 2.5 molecules per molecule of platinum. When the amount exceeds 0.6 molecules per molecule of platinum, the storage stability of the curable organopolysiloxane composition containing the catalyst is good, and the risk of the organopolysiloxane composition gelling is eliminated. On the other hand, when the amount is 3.0 molecules or less per molecule of platinum, even when associated with the silane compound and / or its partial hydrolysate described later, the risk of crystal precipitation at room temperature is eliminated, and the liquid state of the platinum-phosphite ester complex-containing hydrosilylation catalyst can be sufficiently maintained. Furthermore, the dispersibility of the catalyst in the curable organopolysiloxane composition is also good, and no problems such as reduced workability occur.

[0024] [Silane compounds and / or their partial hydrolysates] The following general formula (2) used in this invention [ka] (In the formula, R 2 R represents an alkenyl group with 2 to 10 carbon atoms. 3 X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms. Also, X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms or OR 3 (is) The silane compounds and / or their partial hydrolysates, as shown, associate with the aforementioned platinum-phosphite ester complex and are essential components for preventing crystallization at room temperature.

[0025] In the above general formula (2), R 2R is an alkenyl group having 2 to 10 carbon atoms, preferably 2 to 10 carbon atoms, more preferably 2 to 8 carbon atoms, and most preferably a vinyl group. Also, in formula (2) above, R 3 This refers to a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms. Specifically, examples include methyl, ethyl, propyl, isopropyl, 3-propenyl, and isopropenyl groups. Preferably, it has 1 or 2 carbon atoms, more preferably 1 carbon atom, i.e., a methyl group. Specific examples of siloxane compounds include vinyl trimethoxysilane, vinyl dimethoxymethylsilane, vinyl triethoxysilane, vinyl diethoxymethylsilane, vinyl trimethoxysilane, allyl dimethoxymethylsilane, 7-octenyl trimethoxysilane, 7-octenyl dimethoxymethylsilane, and / or their partial hydrolysates. In the above general formula (2), X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms or OR 3 Specifically, these include methyl, ethyl, propyl, methoxy, ethoxy, propoxy, and isopropoxy groups.

[0026] The optimal amount of the silane compound and / or its partial hydrolysate used in the present invention is within the range of 0.05 mol% to 100 mol% per molecule of platinum, and more preferably, within the range of 0.05 mol% to 90 mol% per molecule of platinum. Here, when the amount is 0.05 mol% or more per molecule of platinum, the resulting platinum-phosphite complex-containing hydrosilylation catalyst does not crystallize at room temperature and can maintain its liquid state. Furthermore, it exhibits good dispersibility in curable organopolysiloxane compositions and does not cause problems such as reduced workability. Also, when the amount is 100 mol% or less per molecule of platinum, the platinum-phosphite complex-containing hydrosilylation catalyst itself is stable, and the amount of effective platinum in the catalyst itself does not decrease. Therefore, when obtaining a curable organopolysiloxane composition containing this catalyst, the amount of compound added is appropriate, as is the amount of the silane compound and / or its partial hydrolysate added, resulting in good mechanical properties and curability.

[0027] One of the features of the platinum-phosphite ester complex-containing hydrosilylation catalyst of the present invention is that it does not contain hydrocarbon organic solvents. Here, "hydrocarbon organic solvent" refers to aliphatic hydrocarbon solvents and aromatic hydrocarbon solvents. Aliphatic hydrocarbon solvents include not only hydrocarbon solvents with a boiling point of 80°C or less used in step (a) of the catalyst manufacturing method described later, but also aliphatic hydrocarbon solvents with a boiling point exceeding 80°C. Specifically, examples include n-pentane, n-hexane, 2-methylbutane, 2,2-dimethylbutane, 2,3-dimethylbutane, 2-methylpentane, 3-methylpentane, n-heptane, and n-octane. Examples of aromatic hydrocarbons include benzene, toluene, xylene, ethylbenzene, and isopropylbenzene.

[0028] [Utilization of hydrosilylation catalysts containing platinum-phosphite complexes] The aforementioned platinum-phosphite complex-containing hydrosilylation catalyst can be used in various applications such as curing catalysts for resins and purification catalysts, but it exhibits its characteristics particularly when used as a curing catalyst for organopolysiloxane compositions that become resins (or gels) using the hydrosilylation reaction. This is because, when heated, it has almost the same curing properties as conventional platinum compound-based hydrosilylation catalysts, and when stored at room temperature, the phosphite compound forms a complex with platinum, suppressing catalytic activity and resulting in a very slow progression of the hydrosilylation reaction. Therefore, curable organopolysiloxane compositions using this catalyst maintain their properties and physical characteristics even when exposed to temperatures above room temperature for extended periods. Furthermore, by associating the complex of the phosphite compound and platinum with the silane compound represented by the general formula (2) and / or its partial hydrolysate, the resulting platinum-phosphite complex-containing hydrosilylation catalyst can be kept in a liquid state at room temperature. Therefore, when this catalyst is incorporated into a curable organopolysiloxane composition, it offers advantages such as good workability and ease of uniform dispersion.

[0029] The amount of the platinum-phosphite complex-containing hydrosilylation catalyst added to the curable organopolysiloxane composition is 0.001 to 10.0 parts by mass, preferably 0.010 to 5.0 parts by mass, and more preferably 0.050 to 3.0 parts by mass, per 100 parts by mass of the alkenyl group-containing polymer. When the amount of the platinum-phosphite complex-containing hydrosilylation catalyst is 0.001 parts by mass or more, the resulting silicone rubber composition has sufficient strength and does not suffer from curing failure. Conversely, when the amount of the platinum-phosphite complex-containing hydrosilylation catalyst is 10.0 parts by mass or less, the resulting silicone rubber composition does not become discolored, the curing time is not shortened, and it is also more cost-effective. The activity of the catalyst, i.e., the curability, can be controlled by increasing or decreasing the concentration of the added platinum-phosphite complex-containing hydrosilylation catalyst.

[0030] [Method for producing a hydrosilylation catalyst containing a platinum-phosphite ester complex] [Process (a)] Step (a) is a step of preparing a solution in which a phosphite compound represented by general formula (1) is dissolved in a hydrocarbon solvent having a boiling point of 80°C or lower. [ka] (In the formula, R 1 (It is a monovalent aliphatic hydrocarbon group having 1 to 3 hydrogen atoms or carbon atoms.)

[0031] If the phosphite ester compound is liquid at room temperature, a complex can be easily formed by mixing it with a platinum compound that does not contain an organic solvent, selected from the group consisting of platinum chloride, platinum chloride, or platinum chloride salts and vinyl group-containing siloxanes, in step (b) below. However, since most of the phosphite ester compounds are solid at room temperature, by dissolving the phosphite ester compound in a hydrocarbon solvent in step (a), a rapid complex formation can be achieved by subsequently mixing it with a platinum compound that does not contain an organic solvent, selected from the group consisting of platinum chloride, platinum chloride, or platinum chloride salts and vinyl group-containing siloxanes.

[0032] Hydrocarbon solvents with a boiling point of 80°C or lower may be linear or branched. Specific examples of hydrocarbon solvents with a boiling point of 80°C or lower include n-pentane (boiling point: 36°C), n-hexane (boiling point: 68°C), 2-methylbutane (boiling point: 30°C), 2,2-dimethylbutane (boiling point: 50°C), 2,3-dimethylbutane (boiling point: 58°C), 2-methylpentane (boiling point: 62°C), and 3-methylpentane (boiling point: 63°C). Among these, n-hexane (boiling point: 68°C) is particularly suitable because it is relatively easy to handle for industrial use and easy to remove in subsequent removal processes. From the viewpoint of vacuum distillation of hydrocarbon solvents, it is preferable that the boiling point of the hydrocarbon solvent used is 80°C or lower. In this process, by setting the reduced-pressure distillation temperature to 40°C or lower, it becomes possible to obtain a stable platinum-phosphite complex-containing hydrosilylation catalyst. In the case of hydrocarbon solvents with a boiling point of 80°C or higher, if the reduced-pressure distillation temperature is not set to 40°C or higher, the used hydrocarbon solvent cannot be completely removed. As a result, hydrocarbon solvents may remain in the platinum-phosphite complex-containing hydrosilylation catalyst, or the catalyst may decompose due to the temperature of the solvent removal process, leading to crystal precipitation.

[0033] Furthermore, there is no particular limit on the amount of hydrocarbon solvent with a boiling point of 80°C or lower used. Also, the temperature at which the phosphite compound represented by general formula (1) is dissolved in the hydrocarbon solvent is 40°C or lower, more preferably in the range of 0 to 35°C. Dissolution at 40°C or lower makes it difficult for the phosphite compound represented by general formula (1) to hydrolyze with the water contained in the hydrocarbon solvent, thus preventing the phosphite compound represented by (1) from changing into a phosphate ester compound, resulting in good stability of the resulting platinum-phosphite complex-containing hydrosilylation catalyst. There is also no particular limit on the dissolution time. For the dissolution container, it is preferable to select one that can block oxygen.

[0034] [Step (b)] Step (b) is a step of adding an organic solvent-free platinum compound, selected from the group consisting of platinum chloride, chloroplatinic acid, or a complex of a chloroplatinate and a vinyl group-containing siloxane, to the solution and dispersing it to prepare a solution containing a platinum-phosphite ester complex.

[0035] [An organic solvent-free platinum compound selected from the group consisting of platinum chloride, chloroplatinic acid, or a complex of a chloroplatinate with a vinyl group-containing siloxane.] The platinum compound used in this invention, selected from the group consisting of platinum chloride, chloroplatinic acid, or chloroplatinate salts and vinyl group-containing siloxanes, is a non-organic solvent platinum compound that typically promotes the hydrosilylation addition of SiH groups in organohydrogenpolysiloxanes to alkenyl group-containing polymers contained in curable organopolysiloxane compositions. In this invention, a phosphite ester compound represented by general formula (1) is used. [ka] (In the formula, R 1 (It is a monovalent aliphatic hydrocarbon group having 1 to 3 hydrogen atoms or carbon atoms.) By forming a complex with it, the storage stability of the properties and physical characteristics of the curable organopolysiloxane composition obtained using it can be dramatically improved, and the silane compound represented by general formula (2) and / or its partial hydrolysate, [ka] (In the formula, R 2 R represents an alkenyl group with 2 to 10 carbon atoms. 3 X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms. Also, X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms or OR 3 (is) By associating with this catalyst, it can become a platinum-phosphite ester complex-containing hydrosilylation catalyst that is liquid at room temperature without containing organic solvents. Therefore, when obtaining a curable organopolysiloxane composition using this catalyst, it is possible to improve the uniform dispersibility of the catalyst and the stability and uniformity of the catalyst itself.

[0036] Specific examples of organic solvent-free platinum compounds selected from the group consisting of platinum chloride, chloroplatinic acid, or chloroplatinate salts and vinyl group-containing siloxanes include platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (Karstedt complex), platinum-1,3-diallyl-1,1,3,3-tetramethyldisiloxane complex, platinum-1,3-divinyl-1,3-dimethyl-1,3-diphenyldisiloxane complex, platinum-1,1,3,3-tetraphenyldisiloxane complex, and platinum-1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane complex. It is essential that the compounds contain at least one hydrosilylation catalyst selected from this group, and that they do not contain organic solvents. Among the above-mentioned hydrosilylation catalysts that do not contain organic solvents, it is especially preferable to use platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (Karstedt complex).

[0037] Platinum compounds selected from the group consisting of platinum chloride, chloroplatinic acid, or chloroplatinate salts and vinyl group-containing siloxanes, as shown herein, must be free from basic organic solvents such as aromatic hydrocarbon organic solvents like toluene and xylene, and alcoholic organic solvents like ethanol, n-butanol, and 2-ethylhexyl alcohol (excluding low molecular weight siloxanes with vinyl groups such as tetramethyldivinylsiloxane, trimethyltrivinylcyclotrisiloxane, and tetramethyltetravinylcyclotetrasiloxane).

[0038] The most commonly used form of a platinum compound, selected from the group consisting of complexes of platinum chloride, chloroplatinic acid, or chloroplatinate salts with vinyl group-containing siloxanes, which does not contain organic solvents, is a solution in a siloxane that forms ligands for the platinum-siloxane complex. The solution is usually prepared to contain approximately 0.001 to 0.010 moles of platinum atoms. This is to enhance the stability of the platinum-siloxane complex. The mass percentage of platinum contained is 0.2 to 2.0%. Examples of compounds that can form platinum-siloxane complexes are tetramethyldivinylsiloxane, trimethyltrivinylcyclotrisiloxane, and tetramethyltetravinylcyclotetrasiloxane. [ka]

[0039] A preferred platinum compound is the platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (Karstedt complex). It is thought to have the following structure: [ka] The time required for this process is preferably 30 minutes or more at a temperature of 40°C or lower. For this process (b), as with process (a), it is preferable to select a container that can block oxygen.

[0040] [Process (c)] Step (c) is a step in which a silane compound represented by the following general formula (2) and / or a partial hydrolysate thereof is added to the solution obtained in steps (a) to (b) above and dispersed to prepare a solution containing at least a portion of the platinum-phosphite ester complex and an aggregate of the silane compound represented by the following general formula (2) and / or a partial hydrolysate thereof. [ka] (In the formula, R 2 R represents an alkenyl group with 2 to 10 carbon atoms. 3X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms. Also, X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms or OR 3 (is)

[0041] This process is preferably carried out at a temperature of 40°C or lower for 60 minutes or more. As with step (a), it is preferable to select a container that can block oxygen during this process. The silane compound represented by general formula (2) and / or its partial hydrolysate used here is selected from the group consisting of platinum chloride, platinum chloride, or platinum chloride salts and vinyl group-containing siloxanes, and contains one platinum atom in the platinum compound free of organic solvents, with R in general formula (2) for each platinum atom. 2 It is preferable to add a silane compound in an amount such that the unit is within the range of 0.01 to 500 times. For each platinum atom in the platinum compound, R in general formula (2) 2 When the unit expressed is 0.01 times or more, the amount of silane compound represented by general formula (2) and / or its partial hydrolysate that associates with one platinum atom becomes sufficient, ensuring that the liquid state is reliably maintained at 23°C, and preventing crystal precipitation that would cause problems such as deterioration of dispersibility or reduced mixing workability in the curable organopolysiloxane composition containing the catalyst. Furthermore, for one platinum atom in the platinum compound, R in general formula (2) 2 When the unit expressed is 500 times or less, the amount of silane compound and / or its partial hydrolysate shown in general formula (2) added becomes appropriate, the molecular weight of the siloxane compound itself does not increase, which does not significantly affect the viscosity of the resulting platinum-phosphite complex-containing hydrosilylation catalyst, nor does it result in poor stability of the properties of the resulting platinum-phosphite complex-containing hydrosilylation catalyst, nor does it cause problems such as reduced workability when formulating the catalyst.

[0042] [Step (d)] Step (d) is a step to remove the hydrocarbon solvent from the solution obtained in steps (a) to (c). This step is essential for removing the hydrocarbon solvent from the solution obtained in steps (a) to (c) and obtaining a platinum-phosphite complex-containing hydrosilylation catalyst that does not contain organic solvents. The solvent removal method used here is preferably a vacuum distillation method in which the solvent is removed under reduced pressure using a vacuum pump or the like. This is because a stable platinum-phosphite complex-containing hydrosilylation catalyst can be obtained by setting the vacuum distillation temperature to 40°C or lower. The degree of vacuum will vary depending on the boiling point of the hydrocarbon solvent used, but the hydrocarbon solvent used can be completely removed by setting the condition to 50 hPa or lower. The method for confirming that the hydrocarbon solvent used has been completely removed is to check the weight ratio of the total weight of the phosphite compound, platinum compound, and silane compound used to the platinum-phosphite complex-containing hydrosilylation catalyst obtained after the completion of step (d). If the weight of the obtained platinum-phosphite complex-containing hydrosilylation catalyst is greater than the total weight of the phosphite compound, platinum compound, and silane compound used, it means that hydrocarbon solvents remain. These can be completely removed by extending the process time to remove the hydrocarbon solvents. [Examples]

[0043] The present invention will be described in detail below with reference to examples and comparative examples, but the present invention is not limited thereto. In the examples, "parts" refers to "parts by mass" and "%" refers to "mass%".

[0044] [Example 1] 0.6622 parts of tris(2,4-di-tert-butylphenyl)phosphite were weighed into a 25g clear glass container, 9.3378 parts of n-hexane were added, and the container was sealed and allowed to dissolve at room temperature for approximately 1 hour. After visually confirming that the tris(2,4-di-tert-butylphenyl)phosphite crystals had dissolved, 10.0 parts of platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex containing 1% Pt atoms were added, the container was sealed, and the mixture was stirred for 30 minutes until homogeneous. Subsequently, 0.06 parts of vinyltrimethoxysilane were added, the container was sealed, and the mixture was stirred for 60 minutes until homogeneous. The solution was then transferred to a 100ml round-bottom flask, and n-hexane was removed by vacuum distillation using a rotary evaporator (conditions: 30°C × 2 hours / approximately 35 hPa). 10.31 g of a colorless, transparent liquid was obtained in a 100 ml round-bottom flask (yield: 96.2%). This platinum-phosphite complex-containing hydrosilylation catalyst will be referred to as "Catalyst 1". (The amount of phosphite ester compound is 2.0 molecules per 1 molecule of platinum in the platinum compound, and the amount of silane compound is 0.79 molecules per 1 molecule of platinum in the platinum compound.)

[0045] [Example 2] 0.3311 parts of tris(2,4-di-tert-butylphenyl)phosphite were weighed into a 25g clear glass container, and 9.6689 parts of n-hexane were added. The container was sealed and allowed to dissolve at room temperature for approximately 1 hour. After visually confirming that the tris(2,4-di-tert-butylphenyl)phosphite crystals had dissolved, 10.0 parts of platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex containing 1% Pt atoms were added. The container was sealed and stirred for 30 minutes until homogeneous. Subsequently, 0.06 parts of vinyltrimethoxysilane were added, the container was sealed and stirred for 60 minutes until homogeneous. The solution was then transferred to a 100ml round-bottom flask, and n-hexane was removed by vacuum distillation using a rotary evaporator (conditions: 30°C for 2 hours / approximately 32 hPa). 10.25 g of a colorless, transparent liquid was obtained in a 100 ml round-bottom flask (yield: 98.7%). This platinum-phosphite complex-containing hydrosilylation catalyst will be referred to as "Catalyst 2". (The amount of phosphite ester compound is 1.0 molecule per 1 molecule of platinum in the platinum compound, and the amount of silane compound is 0.79 molecules per 1 molecule of platinum in the platinum compound.)

[0046] [Example 3] 0.3311 parts of tris(2,4-di-tert-butylphenyl)phosphite were weighed into a 25g clear glass container, 9.6689 parts of n-hexane were added, and the container was sealed and allowed to dissolve at room temperature for approximately 1 hour. After visually confirming that the tris(2,4-di-tert-butylphenyl)phosphite crystals had dissolved, 10.0 parts of platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex containing 1% Pt atoms were added, the container was sealed, and the mixture was stirred for 30 minutes until homogeneous. Subsequently, 1.00 part of vinyltrimethoxysilane was added, the container was sealed, and the mixture was stirred for 60 minutes until homogeneous. The solution was then transferred to a 100ml round-bottom flask, and n-hexane was removed by vacuum distillation using a rotary evaporator (conditions: 30°C × 2 hours / approximately 34 hPa). 11.12 g of a colorless, transparent liquid was obtained in a 100 ml round-bottom flask (yield: 98.1%). This platinum-phosphite complex-containing hydrosilylation catalyst will be referred to as "Catalyst 3". (The amount of phosphite ester compound is 1.0 molecule per 1 molecule of platinum in the platinum compound, and the amount of silane compound is 13.16 molecules per 1 molecule of platinum in the platinum compound.)

[0047] [Example 4] 0.6622 parts of tris(2,4-di-tert-butylphenyl)phosphite were weighed into a 25g clear glass container, and 9.3378 parts of n-hexane were added. The container was sealed and allowed to dissolve at room temperature for approximately 1 hour. After visually confirming that the tris(2,4-di-tert-butylphenyl)phosphite crystals had dissolved, 10.0 parts of platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex containing 1% Pt atoms were added. The container was sealed and stirred for 30 minutes until homogeneous. Subsequently, 0.06 parts of 7-octenyltrimethoxysilane (product name: KBM-1083 [manufactured by Shin-Etsu Chemical Co., Ltd.]) were added. The container was sealed and stirred for 60 minutes until homogeneous. The solution was then transferred to a 100ml round-bottom flask, and n-hexane was removed by vacuum distillation using a rotary evaporator (conditions: 30°C for 2 hours / approximately 35 hPa). 10.31 g of a colorless, transparent liquid was obtained in a 100 ml round-bottom flask (yield: 96.2%). This platinum-phosphite complex-containing hydrosilylation catalyst will be referred to as "Catalyst 4". (The amount of phosphite ester compound is 2.0 molecules per 1 molecule of platinum in the platinum compound, and the amount of silane compound is 0.50 molecules per 1 molecule of platinum in the platinum compound.)

[0048] [Comparative Example 1] In Example 1, the same procedure was followed except that vinyltrimethoxysilane was replaced with 0.06 parts of 2,4,6,8-tetravinyl-2,4,6,8-tetramethylcyclotetrasiloxane. As a result, 10.33 g of a colorless, transparent liquid was obtained in a 100 ml round-bottom flask (yield: 96.3%). This platinum-phosphite complex-containing hydrosilylation catalyst was designated as "Catalyst 5". (The amount of phosphite ester compound is 1.0 molecule per 1 molecule of platinum in the platinum compound, and the amount of silane compound is 0 molecules per 1 molecule of platinum in the platinum compound. [The amount of 2,4,6,8-tetravinyl-2,4,6,8-tetramethylcyclotetrasiloxane, which acts as a ligand, is 0.34 molecules per 1 molecule of platinum in the platinum compound.])

[0049] [Comparative Example 2] In Example 1, the same procedure was followed except that vinyltrimethoxysilane was omitted. As a result, 10.50 g of a colorless, transparent liquid was obtained in a 100 ml round-bottom flask (yield: 98.5%). This platinum-phosphite complex-containing hydrosilylation catalyst was designated as "Catalyst 6". (The amount of phosphite ester compound is 1.0 molecule per 1 molecule of platinum in the platinum compound, and the amount of silane compound is 0 molecules per 1 molecule of platinum in the platinum compound.)

[0050] [Comparative Example 3] 0.3311 parts of tris(2,4-di-tert-butylphenyl)phosphite were weighed into a 25g clear glass container, and 9.6689 parts of n-heptane (boiling point: 98°C) were added. The container was sealed and allowed to dissolve at room temperature for approximately 1 hour. After visually confirming that the tris(2,4-di-tert-butylphenyl)phosphite crystals had dissolved, 10.0 parts of platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex containing 1% Pt atoms were added. The container was sealed and stirred for 30 minutes until homogeneous. Subsequently, 0.06 parts of vinyltrimethoxysilane were added, the container was sealed and stirred for 60 minutes until homogeneous. The solution was then transferred to a 100ml round-bottom flask, and n-hexane was removed by vacuum distillation using a rotary evaporator (conditions: 50°C × 2 hours / approximately 35 hPa). In a 100 ml pear-shaped flask, a colorless, transparent liquid with dispersed white crystals was obtained (yield: 10.95 g), and a colorless, transparent liquid could not be obtained (yield: 105.4%). This platinum-phosphite complex-containing hydrosilylation catalyst will be referred to as "Catalyst 7". (The amount of phosphite ester compound is 1.0 molecule per 1 molecule of platinum in the platinum compound, and the amount of silane compound is 0.79 molecules per 1 molecule of platinum in the platinum compound.)

[0051] [Comparative Example 4] In Example 1, the same procedure as in Example 1 was carried out without using n-hexane. As a result, a liquid containing dispersed white crystals (yield: 10.33 g) was obtained in a 100 ml round-bottom flask, and a colorless, transparent liquid could not be obtained. (Yield: 99.9%). This platinum-phosphite complex-containing hydrosilylation catalyst will be referred to as "Catalyst 8".

[0052] The yields and yields of the platinum-phosphite complex-containing hydrosilylation catalysts obtained in Examples 1-4 and Comparative Examples 1-4 are shown in Table 1. Furthermore, the following tests were performed on the appearance of the catalysts obtained in these examples and comparative examples. The obtained platinum-phosphite ester complex-containing hydrosilylation catalysts were stored in sealed containers filled with nitrogen. After 7 days at 23°C, the appearance was checked. Catalysts that did not show crystal formation were deemed acceptable, while those showing crystal formation were deemed unacceptable. The results are shown in Table 1.

[0053] [Table 1]

[0054] [evaluation] The platinum-phosphite complex-containing hydrosilylation catalysts obtained in Examples 1 to 4 satisfy the requirements of the present invention. In all examples, the amount of phosphite compound used was 1.0 or 2.0 molecules per 1 molecule of platinum in the platinum compound. However, when the same operation was performed in the same manner up to 3.0 molecules per 1 molecule of platinum in the platinum compound, in increments of 0.1 molecules, it was confirmed that a colorless, transparent liquid was obtained in all cases. The platinum-phosphite complex-containing hydrosilylation catalysts obtained in Examples 1 to 4 showed suppressed crystal precipitation even after being left under sealed conditions at 23°C for 7 days, indicating that highly stable platinum-phosphite complex-containing hydrosilylation catalysts were obtained. In contrast, the platinum-phosphite ester complex-containing hydrosilylation catalysts of Comparative Examples 1 and 2 do not contain the silane compound represented by general formula (2) and / or its partial hydrolysate, so it can be seen that crystals precipitate after about 7 days at 23°C. Furthermore, the platinum-phosphite ester complex-containing hydrosilylation catalyst of Comparative Example 3 uses n-heptane, which has a boiling point of 80°C or higher, as a hydrocarbon solvent to dissolve the phosphite ester compound. As a result, even if the temperature of the vacuum distillation is increased, the n-heptane used cannot be completely removed, and as a result of increasing the heating temperature, the coordination of the phosphite ester compound in the platinum-phosphite ester complex-containing hydrosilylation catalyst is detached, causing crystals to precipitate, and it can be seen that a liquid platinum-phosphite ester complex-containing hydrosilylation catalyst cannot be obtained. In the platinum-phosphite ester complex-containing hydrosilylation catalyst of Comparative Example 4, the phosphite ester compound was not dissolved in the hydrocarbon solvent but coordinated to the platinum compound. As a result, it can be seen that the phosphite ester compound did not dissolve and a liquid with dispersed crystals was obtained. The above results confirm the effectiveness of the catalyst production method of the present invention in obtaining a stable liquid platinum-phosphite complex-containing hydrosilylation catalyst.

[0055] [Examples relating to curable organopolysiloxane compositions using a hydrosilylation catalyst containing a platinum-phosphite complex] The following describes specific examples and comparative examples of curable organopolysiloxane compositions utilizing the platinum-phosphite complex-containing hydrosilylation catalyst obtained in the present invention. While the following examples and comparative examples are for one-component millable silicone rubber compositions, the present invention is not limited thereto.

[0056] The evaluation of this embodiment was carried out as follows.

[0057] [Regarding the workability of preparing one-component, millable-type silicone rubber compositions] In the preparation of the one-component millable silicone rubber compositions described in the following examples and comparative examples, those in which the platinum-phosphite complex-containing hydrosilylation catalyst was liquid and no problems occurred during addition were judged to be acceptable. Conversely, those in which the platinum-phosphite complex-containing hydrosilylation catalyst crystallized during catalyst compounding and problems occurred during addition were judged to be unacceptable.

[0058] [Storage stability of one-component, millable-type silicone rubber composition] The storage stability of the one-component millable silicone rubber compositions prepared in the following examples and comparative examples was compared using a rheometer (ALPHA TECHNOLOGIES RUBBER PROCESS ANALYZER RPA2000) to determine the initial curability of the obtained one-component millable silicone rubber composition and the curability after storage at 23°C for 6 months. A composition that could be evaluated for 6 months at 23°C was deemed acceptable. Here, the curability data for the one-component millable silicone rubber composition is shown as measured at 150°C. In Table 2, T50* and T50** are defined as the time T from when the torque rises until it reaches 50%, assuming that 100% hardening occurs when the torque stabilizes, as seen in the time-torque curve at 150°C.

[0059] [Composition Example 1] 100 parts by mass of organopolysiloxane raw rubber consisting of 99.85 mol% dimethylsiloxane units, 0.125 mol% methylvinylsiloxane units, and 0.025 mol% dimethylvinylsiloxy units, with an average degree of polymerization of 6,000, and a specific surface area of ​​200 m² by BET method. 2 55 parts by mass of fumed silica (Aerosil 200, manufactured by Nippon Aerosil Co., Ltd.) at a concentration of / g, 12 parts by mass of dimethyldimethoxysilane, 0.2 parts by mass of vinyltrimethoxysilane, 12 parts by mass of dimethylpolysiloxane having silanol groups at both ends, an average degree of polymerization of 4, and a viscosity of 15 mPa·s at 25°C, and 0.15 parts by mass of 3% potassium silicate were added, and the mixture was heated at 170°C for 2 hours under mixing conditions using a kneader to prepare base compound (1). In the base compound (1), a set structure is M2D with respect to 100 parts by mass of organopolysiloxane raw rubber. H 20 D 18 (H amount: 0.00726 mol / g) (where M: (CH3)3SiO 1 / 2 -, D H :(CH3)HSiO 2 / 2 -,D:(CH3)2SiO 2 / 2 1.7 parts by mass of organohydrogensiloxane (represented by -) and 0.05 parts by mass of "Catalyst 1" prepared in Example 1 were added using a two-roll mixer and uniformly mixed to produce a raw rubber-like one-component silicone rubber composition 1.

[0060] [Composition Example 2] A one-component silicone rubber composition 2 was prepared in the same manner as in Composition Example 1, except that 0.05 parts by mass of Catalyst 2 was used instead of Catalyst 1.

[0061] [Composition Example 3] A one-component silicone rubber composition 3 was prepared in the same manner as in Composition Example 1, except that 0.05 parts by mass of Catalyst 3 was used instead of Catalyst 1.

[0062] [Composition Example 4] A one-component silicone rubber composition 4 was prepared in the same manner as in Composition Example 1, except that 0.05 parts by mass of Catalyst 4 was used instead of Catalyst 1.

[0063] [Comparative Example of Composition 1] A one-component silicone rubber composition 5 was prepared in the same manner as in Composition Example 1, except that 0.05 parts by mass of catalyst 5 was used instead of catalyst 1.

[0064] [Comparative Example of Composition 2] A one-component silicone rubber composition 6 was prepared in the same manner as in Composition Example 1, except that 0.05 parts by mass of catalyst 6 was used instead of catalyst 1.

[0065] [Comparative Example of Composition 3] A one-component silicone rubber composition 7 was prepared in the same manner as in Composition Example 1, except that 0.05 parts by mass of catalyst 7 was used instead of catalyst 1.

[0066] [Comparative Example of Composition 4] A one-component silicone rubber composition 8 was prepared in the same manner as in Composition Example 1, except that 0.05 parts by mass of Catalyst 8 was used instead of Catalyst 1.

[0067] [Comparative Example of Composition 5] A one-component silicone rubber composition 9 was prepared in the same manner as in Composition Example 1, except that 0.05 parts by mass of a platinum-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex having 1% Pt atoms was used instead of "Catalyst 1".

[0068] [test] The results obtained for the above-mentioned Composition Examples 1-4 and Composition Comparative Examples 1-5 are shown in Table 2.

[0069] [Table 2]

[0070] [Composition Evaluation] The platinum-phosphite ester complex-containing hydrosilylation catalysts obtained in Examples 1 to 4 satisfy the requirements of the present invention, and the curable organopolysiloxane compositions of Examples 1 to 4 using these catalysts exhibit good storage stability at 23°C. In contrast, the platinum-phosphite ester complex-containing hydrosilylation catalysts of Comparative Examples 1 to 4 failed the catalyst quality test because crystals precipitated at 23°C. Furthermore, they failed in terms of workability because it was necessary to remove the crystalline components while adding the required amount of catalyst. However, the curable organopolysiloxane compositions using these catalysts showed good storage stability. Therefore, if the catalyst becomes liquid at 23°C, the workability during catalyst addition will also improve. In addition, the platinum-phosphite ester complex-containing hydrosilylation catalyst of Comparative Example 4 was obtained without using hydrocarbon solvents. As a result, the complex formation between the phosphite ester compound and platinum was poor, and the curable silicone composition prepared using it had reduced storage stability. Comparative Example 5 is an example of a curable organopolysiloxane composition that directly uses an organic solvent-free platinum compound selected from the group consisting of chloroplatinic acid or chloroplatinate salt and a vinyl group-containing siloxane, without complex formation between platinum and phosphite ester or association with a siloxane compound. The curable organopolysiloxane composition prepared using this catalyst showed reduced storage stability. From the above results, it can be seen that the curable organopolysiloxane composition using the platinum-phosphite ester complex-containing hydrosilylation catalyst obtained in the present invention exhibits excellent performance in terms of improved workability and storage stability.

[0071] This specification includes the following embodiments: [1]: (A) Platinum and the following general formula (1) [ka] (In the formula, R 1 (It is a monovalent aliphatic hydrocarbon group having 1 to 3 hydrogen atoms or carbon atoms.) A platinum-phosphorite ester complex composed of a phosphite ester compound represented by, and (B) Silane compounds represented by the following general formula (2) and / or partial hydrolysates thereof, A hydrosilylation catalyst containing a platinum-phosphite ester complex, [ka] (In the formula, R 2 R represents an alkenyl group with 2 to 10 carbon atoms. 3 X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms. Also, X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms or OR 3 (That is the case.) The hydrosilylation catalyst is an aggregate of component (A) and component (B), does not contain an organic solvent, and is liquid at 23°C, characterized in that it is a platinum-phosphite complex-containing hydrosilylation catalyst. [2]: The component (B) is the R 2 A platinum-phosphite complex-containing hydrosilylation catalyst as described in [1], characterized in that the alkoxysilane derivative is a vinyl group. [3]: A curable organopolysiloxane composition characterized by containing a platinum-phosphite complex-containing hydrosilylation catalyst as described in [1] or [2]. [4]: The curable organopolysiloxane composition according to [3], characterized in that it does not contain an organic solvent. [5]: An article having a cured product of a curable organopolysiloxane composition described in [3] or [4]. [6] A method for producing a platinum-phosphite complex-containing hydrosilylation catalyst, characterized by comprising the following steps (a) to (d). (a) A step of preparing a solution by dissolving a phosphite ester compound represented by the following general formula (1) in a hydrocarbon solvent having a boiling point of 80°C or lower, [ka] (In the formula, R 1 (It is a monovalent aliphatic hydrocarbon group having 1 to 3 hydrogen atoms or carbon atoms.) (b) A step of adding an organic solvent-free platinum compound, selected from the group consisting of platinum chloride, chloroplatinic acid, or a complex of a chloroplatinate and a vinyl group-containing siloxane, to the solution and dispersing it to prepare a solution containing a platinum-phosphite complex. (c) A step of adding a silane compound represented by the following general formula (2) and / or a partial hydrolysate thereof to the solution obtained in steps (a) to (b) above and dispersing it to prepare a solution containing at least a portion of the platinum-phosphite ester complex and an aggregate of the silane compound represented by the following general formula (2) and / or a partial hydrolysate thereof. [ka] (In the formula, R 2 R represents an alkenyl group with 2 to 10 carbon atoms. 3 X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms. Also, X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms or OR 3 (That is the case.) (d) A step of removing the hydrocarbon solvent from the solution obtained in step (c). [7]: A method for producing a platinum-phosphite complex-containing hydrosilylation catalyst according to [6], characterized in that, in step (c), the silane compound and / or its partial hydrolysate is added such that the number of moles of alkenyl groups in the silane compound and / or its partial hydrolysate is in the range of 0.01 to 500 times per platinum atom in the platinum compound.

[0072] It should be noted that the present invention is not limited to the embodiments described above. The embodiments described above are illustrative, and any configuration that is substantially identical to the technical idea described in the claims of the present invention and achieves similar effects is included within the technical scope of the present invention. [Industrial applicability]

[0073] The platinum-phosphite ester complex-containing hydrosilylation catalyst of the present invention can maintain its liquid state at 23°C without using organic solvents, even in conventional platinum-phosphite ester complex-containing hydrosilylation catalysts that tend to form crystals. Therefore, it is possible to improve the stability of the properties of the hydrosilylation catalyst itself, improve the workability when producing curable organopolysiloxane compositions using this catalyst, and obtain a highly safe curable organopolysiloxane composition that does not contain hydrocarbon-based organic solvents. As a result, it is a platinum-phosphite ester complex-containing hydrosilylation catalyst that has very few adverse effects on the human body. Furthermore, the resulting curable organopolysiloxane composition that does not contain hydrocarbon-based organic solvents can be an organopolysiloxane composition with stable properties and physical characteristics even when exposed to temperatures above room temperature for a long period of time, so it can be expected to have a wide range of applications in fields such as electrical equipment, automobiles, construction, medicine, and food.

Claims

1. (A) Platinum and the following general formula (1) 【Chemistry 1】 (In the formula, R １ (This refers to a monovalent aliphatic hydrocarbon group having 1 to 3 hydrogen atoms or carbon atoms.) A platinum-phosphorite ester complex composed of a phosphite ester compound represented by, and (B) Silane compounds represented by the following general formula (2) and / or partial hydrolysates thereof, A hydrosilylation catalyst containing a platinum-phosphite complex, 【Chemistry 2】 (In the formula, R ２ R represents an alkenyl group having 2 to 10 carbon atoms. ３ X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms. Also, X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms or OR ３ (That is the case.) The hydrosilylation catalyst is an aggregate of component (A) and component (B), does not contain an organic solvent, and is liquid at 23°C, characterized in that it is a platinum-phosphite complex-containing hydrosilylation catalyst.

2. The aforementioned component (B) is R ２ The platinum-phosphite complex-containing hydrosilylation catalyst according to claim 1, characterized in that the alkoxysilane derivative is a vinyl group.

3. A curable organopolysiloxane composition characterized by containing a platinum-phosphite complex-containing hydrosilylation catalyst as described in claim 1 or claim 2.

4. The curable organopolysiloxane composition according to claim 3, characterized in that it does not contain an organic solvent.

5. An article characterized by having a cured product of the curable organopolysiloxane composition described in claim 3.

6. A method for producing a platinum-phosphite complex-containing hydrosilylation catalyst, characterized by comprising the following steps (a) to (d). (a) A step of preparing a solution in which a phosphite ester compound represented by the following general formula (1) is dissolved in a hydrocarbon solvent having a boiling point of 80°C or lower. 【Transformation 3】 (In the formula, R １ (This refers to a monovalent aliphatic hydrocarbon group having 1 to 3 hydrogen atoms or carbon atoms.) (b) A step of adding an organic solvent-free platinum compound, selected from the group consisting of platinum chloride, chloroplatinic acid, or a complex of a chloroplatinate and a vinyl group-containing siloxane, to the solution and dispersing it to prepare a solution containing a platinum-phosphite complex. (c) A step of adding a silane compound represented by the following general formula (2) and / or a partial hydrolysate thereof to the solution obtained in steps (a) to (b) above, and dispersing it to prepare a solution containing an aggregate of at least a portion of the platinum-phosphite ester complex and the silane compound represented by the following general formula (2) and / or a partial hydrolysate thereof. 【Chemistry 4】 (In the formula, R ２ represents an alkenyl group having 2 to 10 carbon atoms, and R ３ is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms. Further, X is a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms or OR ３ .) (d) A step of removing the hydrocarbon solvent from the solution obtained in step (c).

7. The method for producing a platinum-phosphite complex-containing hydrosilylation catalyst according to claim 6, characterized in that, in step (c) above, the silane compound and / or its partial hydrolysate is added such that the number of moles of alkenyl groups in the silane compound and / or its partial hydrolysate is in the range of 0.01 to 500 times per platinum atom in the platinum compound.

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