Polysiloxane composition and use thereof

Abstract

The present disclosure provides a polysiloxane composition and use thereof. A polysiloxane composition according to the present disclosure contains: a component (A) that is a branched polysiloxane represented by a prescribed average unit formula; a component (B) that is a polysiloxane represented by a prescribed average unit formula; and a component (C) that is an organic solvent. In the composition, the content of the polysiloxane constituting component (B) is an amount such that the number of moles of silicon atom-bonded hydrogen atoms in the component (B) per mole of silanol groups in the component (A) is 0.2 to 3.0 moles.

Description

Polysiloxane composition and its uses

[0001] The present disclosure relates to polysiloxane compositions and their uses.

[0002] Polysiloxanes have high heat resistance and excellent chemical stability, and are therefore used as coating agents, potting agents, insulating materials, etc. for electronic and electrical devices.

[0003] Low-refractive index materials are used in various display devices, such as those for mobile devices, industrial equipment, and car navigation systems, for purposes such as anti-reflection and protection of various functional components. Fluorinated polymer materials are well-known as representative low-refractive index materials. However, recent research has revealed that fluorinated polymer materials are persistently biodegradable, highly bioaccumulative, and have concerns about their safety for living organisms. Therefore, there is a global movement to restrict fluorinated polymer materials. Polysiloxane-containing coating materials are attracting attention as alternative materials.

[0004] For example, Patent Document 1 discloses a composition containing an organopolysiloxane compound represented by a predetermined average formula and a solvent having a predetermined structure. Patent Document 2 also discloses a silicone composition containing (A) a polyorganosiloxane having at least two hydroxyl groups (silanol groups) bonded to silicon atoms per molecule, (B) a polyorganohydrogensiloxane having at least three hydrogen atoms (silicon-bonded hydrogen atoms) per molecule, and (C) a condensation reaction catalyst, wherein the amounts of (B) and (C) are each within a predetermined range.

[0005] International Publication No. 2020 / 036074 Japanese Patent Application Laid-Open No. 2015-166432

[0006] The present disclosure provides a polysiloxane composition and uses thereof. In some embodiments, the present disclosure provides a polysiloxane composition that can form a coating film having a low refractive index and excellent solvent resistance, and that has excellent applicability to a substrate, and uses thereof.

[0007] The present disclosure provides, for example, polysiloxane compositions [1] to

[10] , an insulating coating agent

[11] , an insulating coating

[12] , a method for producing an insulating coating

[13] , and a display device

[14] , which are described below.

[0008] [1] (A) The following average unit formula (1): (In formula (1), R １ are each independently a hydrogen atom, a monovalent aliphatic hydrocarbon group having from 1 to 6 carbon atoms, or a monovalent aromatic hydrocarbon group having from 6 to 12 carbon atoms; R ２ is a monovalent hydrocarbon group having 1 to 4 carbon atoms, and a, b, c, d, e1, and e2 are numbers that satisfy the following conditions: 0≦a≦0.4; 0≦b≦0.5; 0.4≦c<1; 0≦d≦0.6; 0<e1≦0.3; 0≦e2<0.3; 0.03≦e1+e2≦0.3; a+b>0; a+b+c+d=1; (B) a branched polysiloxane represented by the following average unit formula (2): (In formula (2), R ３ are each independently a hydrogen atom, a monovalent aliphatic hydrocarbon group having from 1 to 6 carbon atoms, or a monovalent aromatic hydrocarbon group having from 6 to 12 carbon atoms, provided that formula (2) is [H(CH3)2SiO 1 / 2 ], [H(CH3)SiO 2 / 2 ], and [HSiO 3 / 2 and R ４ is a hydrogen atom or a monovalent hydrocarbon group having from 1 to 4 carbon atoms, and f, g, h, i, and j are numbers that satisfy the following conditions: 0≦f≦1; 0≦g≦1; 0≦h<1; 0≦i≦0.6; 0≦j≦0.1; f+g+h+i=1; and (C) an organic solvent, wherein the content of component (B) is such that the number of moles of silicon-bonded hydrogen atoms in component (B) per mole of silanol groups in component (A) is 0.2 to 3.0 moles.

[0009] [2] R in the average unit formula (1) １The polysiloxane composition according to [1] above, wherein the methyl group is contained and the monovalent aromatic hydrocarbon group having 6 to 12 carbon atoms is not contained.

[0010] [3] The polysiloxane composition according to [1] or [2] above, wherein in the average unit formula (2), 0<f.

[0011] [4] The polysiloxane composition according to any one of [1] to [3] above, wherein in the average unit formula (2), 0<h+i.

[0012] [5] The polysiloxane composition according to any one of [1] to [4] above, wherein the weight average molecular weight of the component (A) is 50,000 to 500,000.

[0013] [6] The polysiloxane composition according to any one of [1] to [5] above, wherein d in the average unit formula (1) is 0.

[0014] [7] The polysiloxane composition according to any one of [1] to [6] above, wherein the component (C) is an organic solvent that does not contain benzene, toluene, ethylbenzene, or xylene.

[0015] [8] The polysiloxane composition according to any one of [1] to [7] above, further comprising (D) a platinum-based compound.

[0016] [9] The polysiloxane composition according to any one of [1] to [8] above, wherein the content of component (C) is 20 to 5,000 parts by mass per 100 parts by mass of the total mass of components (A) and (B).

[0017]

[10] The polysiloxane composition according to any one of [1] to [9] above, wherein the content of component (B) is an amount such that the number of moles of silicon-bonded hydrogen atoms in component (B) per mole of silanol groups in component (A) is 0.2 moles or more but less than 1.0 mole.

[0018]

[11] An insulating coating agent comprising the polysiloxane composition according to any one of [1] to

[10] above.

[0019]

[12] An insulating coating formed using the polysiloxane composition according to any one of [1] to

[10] above.

[0020]

[13] A method for producing an insulating coating, comprising the steps of removing the component (C) from the polysiloxane composition according to any one of [1] to

[10] above to obtain a dried product, and heating the dried product at a temperature of 150°C or higher to react the component (A) with the component (B).

[0021]

[14] A display device comprising a layer made of a solid material formed using the polysiloxane composition according to any one of [1] to

[10] above. The display device may be, for example, a liquid crystal display, an organic electroluminescence display, or an organic electroluminescence flexible display.

[0022] According to the present disclosure, it is possible to provide a polysiloxane composition and uses thereof. In some embodiments disclosed herein, a polysiloxane composition capable of forming a coating film having a low refractive index and excellent solvent resistance, and having excellent applicability to a substrate, and uses thereof are provided.

[0023] Embodiments of the present disclosure are described in detail below. The upper and lower limit values ​​of the numerical ranges described herein can be arbitrarily combined. For example, when a numerical range is described as "preferably 30 to 100, more preferably 40 to 80," the ranges "30 to 80" and "40 to 100" are also included in the numerical ranges described herein. Furthermore, when a numerical range is described as "preferably 30 or more, more preferably 40 or more, and preferably 100 or less, more preferably 80 or less," the ranges "30 to 80" and "40 to 100" are also included in the numerical ranges described herein. Additionally, when a numerical range described herein as "60 to 100," for example, means a range of "60 or more and 100 or less."

[0024] (Polysiloxane Composition) The polysiloxane composition of the present disclosure contains, as essential components, a branched polysiloxane as component (A), a polysiloxane as component (B), and an organic solvent as component (C). Here, in the polysiloxane composition of the present disclosure, when the total number of silanol groups in component (A) is taken as 1 mole, the total number of moles of silicon-bonded hydrogen atoms in component (B) is 0.2 to 3.0 moles. Furthermore, the polysiloxane composition of the present disclosure may contain other optional components in addition to components (A), (B), and (C).

[0025] <Component (A): Branched Polysiloxane> The branched polysiloxane, which is component (A), has the following specific composition.

[0026] <<Composition of Component (A)>> Component (A) is represented by the following average unit formula (1).

[0027] In the above formula (1), R １ are each independently a hydrogen atom, a monovalent aliphatic hydrocarbon group having from 1 to 6 carbon atoms, or a monovalent aromatic hydrocarbon group having from 6 to 12 carbon atoms; R ２ is a monovalent hydrocarbon group having 1 to 4 carbon atoms, and a, b, c, d, e1, and e2 are numbers that satisfy the following conditions: 0≦a≦0.4; 0≦b≦0.5; 0.4≦c<1; 0≦d≦0.6; 0<e1≦0.3; 0≦e2<0.3; 0.03≦e≦0.3; a+b>0; a+b+c+d=1. In this specification, the composition of the branched polysiloxane, which is component (A), is １３ C-NMR spectroscopy and ２９ The identification can be performed by nuclear magnetic resonance spectroscopy such as Si-NMR spectroscopy.

[0028] The monofunctional siloxane unit "R １ (CH ３ ) ２ SiO １／２ "R" １ may be one type or two or more types. That is, the branched polysiloxane of component (A) may contain only one type of monofunctional siloxane unit, or may contain two or more types.１ (CH ３ ) SiO ２／２ "R" １ may be one type or two or more types. That is, the branched polysiloxane of component (A) may contain only one type of difunctional siloxane unit, or may contain two or more types. １ SiO ３／２ "R" １ may be one type or two or more types. In other words, the branched polysiloxane of component (A) may contain only one type of trifunctional siloxane unit, or may contain two or more types. ２ O １／２ (OZ group) R ２ may be one type or two or more types. That is, the branched polysiloxane of component (A) is ２ O １／２ It may contain only one kind or two or more kinds.

[0029] In the above formula (1), R １ As described above, R is a hydrogen atom, a monovalent aliphatic hydrocarbon group having 1 to 6 carbon atoms, or a monovalent aromatic hydrocarbon group having 6 to 12 carbon atoms. １ The monovalent aliphatic hydrocarbon group having 1 to 6 carbon atoms constituting R is not particularly limited, but examples thereof include linear or branched saturated aliphatic hydrocarbon groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, sec-butyl, pentyl, and hexyl groups; cyclic saturated aliphatic hydrocarbon groups such as cyclopentyl and cyclohexyl groups; and alkenyl groups such as vinyl, allyl, butenyl, and hexenyl groups. １ The monovalent aromatic hydrocarbon group having 6 to 12 carbon atoms constituting the formula (I) is not particularly limited, but examples thereof include aryl groups such as a phenyl group and a naphthyl group; and arylalkyl groups such as a benzyl group and a phenylethyl group.

[0030] In some embodiments, R in formula (1) above １In consideration of the refractive index of component (A), R in the above formula (1) may contain a linear aliphatic saturated hydrocarbon group, or may contain at least one selected from the group consisting of a methyl group, a vinyl group, and an n-propyl group, or may contain at least one of a methyl group and an n-propyl group, or may contain a methyl group. １ In some embodiments, R in the above formula (1) may not contain a monovalent aromatic hydrocarbon group having 6 to 12 carbon atoms, taking into consideration the refractive index of the component (A). １ In consideration of the refractive index of component (A), all of the groups may be at least one of methyl groups and n-propyl groups, or all of the groups may be methyl groups.

[0031] In the above formula (1), R ２ As described above, R is a monovalent hydrocarbon group having 1 to 4 carbon atoms. ２ The monovalent hydrocarbon group having 1 to 4 carbon atoms constituting the formula (I) is not particularly limited, but examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a tert-butyl group, and a sec-butyl group.

[0032] In some embodiments, R in formula (1) above ２ may be a group selected from the group consisting of methyl and ethyl groups, or may be a methyl group.

[0033] In the above formula (1), the monofunctional siloxane unit "R １ (CH ３ ) ２ SiO １／２" satisfies 0≦a≦0.4 (in other words, 0 or more and 0.4 or less). That is, the monofunctional siloxane unit does not need to be contained in the branched polysiloxane. In some embodiments, the ratio a may be 0.05 or more, or 0.09 or more. At the same time, the ratio a may be 0.3 or less, or 0.25 or less, or 0.2 or less. When the ratio a is greater than 0, that is, when the branched polysiloxane contains a monofunctional siloxane unit, it becomes easy to control the molecular weight of the branched polysiloxane. On the other hand, when the ratio a is 0.4 or less, it is possible to suppress a decrease in the softening point and strength (coating film strength) of a coating film formed using the polysiloxane composition.

[0034] In the above formula (1), the bifunctional siloxane unit "R １ (CH ３ ) SiO ２／２ " satisfies 0≦b≦0.5 (in other words, 0 or more and 0.5 or less). That is, the bifunctional siloxane unit does not have to be contained in the branched polysiloxane. In some embodiments, the ratio b may be 0.4 or less, or 0.3 or less, or 0.2 or less. When the ratio b is 0.5 or less, it is possible to suppress a decrease in the softening point and strength (coating strength) of a coating film formed using the polysiloxane composition. As mentioned above, in some embodiments, the branched polysiloxane does not have to contain a bifunctional siloxane unit. On the other hand, when the branched polysiloxane contains a bifunctional siloxane unit, it has the advantage of facilitating molecular weight control of the branched polysiloxane and imparting flexibility to a coating film formed using the polysiloxane composition. Furthermore, in the above formula (1), the ratio a of the monofunctional siloxane unit and the ratio b of the difunctional siloxane unit satisfy a + b > 0. That is, the branched polysiloxane of component (A) contains either or both of a monofunctional siloxane unit and a difunctional siloxane unit, which makes it easy to control the molecular weight of the branched polysiloxane.

[0035] In the above formula (1), the trifunctional siloxane unit "R １ SiO ３／２" satisfies 0.4≦c<1 (in other words, 0.4 or more and less than 1). That is, the trifunctional siloxane unit is the main structural unit of the branched polysiloxane. In some embodiments, the ratio c may be 0.5 or more, alternatively 0.6 or more, or alternatively 0.7 or more. A ratio c of 0.4 or more can increase the softening point of a coating film formed using the polysiloxane composition. In some embodiments, the ratio c may be 0.95 or less, alternatively 0.92 or less.

[0036] In the above formula (1), the tetrafunctional siloxane unit "SiO ４／２ " satisfies 0≦d≦0.6 (in other words, 0 or more and 0.6 or less). That is, like the monofunctional and difunctional siloxane units, tetrafunctional siloxane units may not be contained in the branched polysiloxane. In some embodiments, the ratio d may be 0.4 or less, alternatively 0.2 or less, alternatively 0.1 or less, or 0 (in other words, the branched polysiloxane does not contain tetrafunctional siloxane units). A ratio d of 0.6 or less can reduce the brittleness of a coating film formed using the polysiloxane composition. As described above, in some embodiments, the branched polysiloxane does not need to contain tetrafunctional siloxane units. On the other hand, the inclusion of tetrafunctional siloxane units in the branched polysiloxane has the advantage of increasing the softening point of a coating film formed using the polysiloxane composition.

[0037] In the above formula (1), the sum of the ratios a, b, c, and d satisfies a+b+c+d=1.

[0038] In the above formula (1), "HO １／２The ratio e1 in " satisfies 0 < e1 ≦ 0.3 (in other words, greater than 0 and equal to or less than 0.3). When the ratio e1 is greater than 0, component (A) can react well with component (B), which will be described later, and the solvent resistance of the coating film obtained from the polysiloxane composition is improved. Furthermore, when the ratio e1 is 0.3 or less, the storage stability of the polysiloxane composition and its applicability to substrates can be improved. In some embodiments, the ratio e1 may be 0.03 or more, or 0.05 or more, or 0.07 or more. At the same time, the ratio e1 may be 0.2 or less, or 0.1 or less.

[0039] In the above formula (1), "R ２ O １／２ The ratio e2 of "R" satisfies 0≦e1<0.3 (in other words, 0 or more and less than 0.3). ２ O １／２ " may not be included in the branched polysiloxane. In some embodiments, the ratio e2 may be 0.2 or less, alternatively 0.1 or less, alternatively 0.05 or less, or alternatively 0.

[0040] In the above formula (1), the sum of the ratios e1 and e2 (e1 + e2) satisfies 0.03≦e1 + e2≦0.3 (in other words, 0.03 or more and 0.3 or less). When e1 + e2 is 0.03 or more, the coatability to a substrate can be improved, and when it is 0.3 or less, the storage stability of the polysiloxane composition and the coatability to a substrate can be improved. In some embodiments, e1 + e2 may be 0.2 or less, or 0.15 or less.

[0041] In some embodiments, the number (average value) of silanol groups (SiOH) contained per molecule of the branched polysiloxane of component (A) may be 2 or more, and the number of silanol groups may be 500 or less, or 300 or less, or 200 or less.

[0042] In some embodiments, from the viewpoint of further improving the storage stability and coatability of the polysiloxane composition to a substrate, the branched polysiloxane of component (A) may have a silanol group content per mole of silicon atom of 0.03 moles or more, and the silanol group content may be 0.2 moles or less, or 0.15 moles or less.

[0043] The weight-average molecular weight of the branched polysiloxane, component (A), is not particularly limited. In some embodiments, the weight-average molecular weight of component (A) may be 1,000 or more, alternatively 5,000 or more, alternatively 10,000 or more, or alternatively 50,000 or more. At the same time, the weight-average molecular weight of component (A) may be 500,000 or less, alternatively 300,000 or less, or alternatively 200,000 or less. When the weight-average molecular weight of component (A) is within the above-described range, the applicability of the polysiloxane composition to a substrate can be improved. In this specification, the terms "weight-average molecular weight" and "number-average molecular weight," as described below, respectively refer to the molecular weight measured by gel permeation chromatography (GPC) in terms of standard polystyrene.

[0044] The polydispersity index (hereinafter sometimes referred to as "PDI") of the branched polysiloxane, component (A), is not particularly limited. In some embodiments, the polydispersity index of component (A) may be, for example, 1.5 or more and 30 or less. The higher the weight average molecular weight described above, the larger the PDI value tends to be. Note that PDI is defined as the value of "Mw / Mn" using the number average molecular weight (Mn) and the weight average molecular weight (Mw).

[0045] The softening point and glass transition temperature of the branched polysiloxane of component (A) are not particularly limited. In some embodiments, the glass transition temperature of component (A) may be 30°C or higher. If the glass transition temperature of component (A) is 30°C or higher, the tackiness (adhesion) of the coating film surface can be reduced when the polysiloxane composition is applied to a substrate to form a coating film. In addition to reducing tackiness, taking into consideration the usage environment of electronic and electrical devices, particularly display devices, in which a coating film of the polysiloxane composition is used, the glass transition temperature may be 60°C or higher, or 100°C or higher. In this specification, the "glass transition temperature" of component (A) can be determined by a measurement method using a differential scanning calorimeter.

[0046] <<Method for Preparing Component (A)>> There are no particular limitations on the method for preparing the branched polysiloxane serving as component (A). Component (A) can be prepared using, for example, the following methods 1), 2), or 3). 1) A method in which a mixture containing starting materials including a plurality of alkoxysilanes and / or linear siloxanes, a reaction solvent, and an acidic catalyst is heated to carry out a hydrolysis and condensation reaction, thereby preparing a branched polysiloxane solution. 2) A method in which a mixture containing the same starting materials, reaction solvent, and basic catalyst as in method 1) is heated to carry out a hydrolysis and condensation reaction, thereby preparing a branched polysiloxane solution. 3) A method in which a mixture containing the same starting materials, reaction solvent, and acidic catalyst as in method 1) is heated to carry out a hydrolysis and condensation reaction, and then a basic catalyst is added to the resulting reaction solution to further react, thereby preparing a branched polysiloxane. In the above methods 1) to 3), operations such as removal of by-product alcohol and excess water, neutralization, and / or filtration may be performed at any time, as needed.

[0047] Among the above-mentioned methods 1) to 3), methods 1) and 3) are preferably applicable. Furthermore, since heavy metals such as platinum atoms are not contained in the products obtained by any of the above-mentioned methods 1) to 3), these methods are advantageous when applied to electronic materials, particularly electronic materials in the semiconductor field.

[0048] The method 3) above will be further explained with a specific example. First, a silicon-based monomer mixture consisting of one or two selected from hexamethyldisiloxane and dimethyldimethoxysilane and methyltrimethoxysilane is dissolved in methylcyclohexane as a reaction solvent, and aqueous hydrochloric acid is added as an acidic catalyst to obtain a mixture. This mixture is heated to carry out a hydrolysis and condensation reaction, yielding a reaction solution containing a reactive branched polysiloxane with a low degree of condensation. A basic catalyst, aqueous potassium hydroxide, is added to this reaction solution to make the reaction system basic. After that, the by-product methyl alcohol and excess water are removed, and the mixture is subjected to a neutralization and filtration process to obtain a highly condensed polysiloxane copolymer as component (A). The structure and molecular weight of the resulting component (A) can be controlled by the ratio of alkoxysilanes and / or linear siloxanes during the reaction, the type and amount of reaction solvent, the amount of water used, and the amount of basic catalyst.

[0049] <Component (B): Polysiloxane> The polysiloxane that is component (B) has the following specific composition.

[0050] <<Composition of Component (B)>> Component (B) is represented by the following average unit formula (2).

[0051] In the above formula (2), R ３ are each independently a hydrogen atom, a monovalent aliphatic hydrocarbon group having from 1 to 6 carbon atoms, or a monovalent aromatic hydrocarbon group having from 6 to 12 carbon atoms, provided that formula (2) is [H(CH3)2SiO 1 / 2 ], [H(CH3)SiO 2 / 2 ], and [HSiO 3 / 2 and R ４ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 4 carbon atoms, and f, g, h, i, and j are numbers that satisfy the following conditions: 0≦f≦1; 0≦g≦1; 0≦h<1; 0≦i≦0.6; 0≦j≦0.1; f+g+h+i=1. In this specification, the composition of the polysiloxane, which is component (B), is defined as follows: １３ C-NMR spectroscopy and ２９The identification can be performed by nuclear magnetic resonance spectroscopy such as Si-NMR spectroscopy.

[0052] The monofunctional siloxane unit "R ３ (CH ３ ) ２ SiO １／２ "R" ３ may be one type or two or more types. That is, the polysiloxane of component (B) may contain only one type of monofunctional siloxane unit, or may contain two or more types. ３ (CH ３ ) SiO ２／２ "R" ３ may be one type or two or more types. That is, the polysiloxane of component (B) may contain only one type of difunctional siloxane unit, or may contain two or more types. ３ SiO ３／２ "R" ３ may be one type or two or more types. That is, the polysiloxane of component (B) may contain only one type of trifunctional siloxane unit, or may contain two or more types. ４ O １／２ (OZ group) R ４ may be one type or two or more types. That is, the polysiloxane of component (B) is ４ O １／２ It may contain only one kind or two or more kinds.

[0053] In the above formula (2), R ３ As described above, is a hydrogen atom, a monovalent aliphatic hydrocarbon group having 1 to 6 carbon atoms, or a monovalent aromatic hydrocarbon group having 6 to 12 carbon atoms.

[0054] R ３The monovalent aliphatic hydrocarbon group having 1 to 6 carbon atoms constituting R is not particularly limited, but examples thereof include linear or branched saturated aliphatic hydrocarbon groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, sec-butyl, pentyl, and hexyl groups; and cyclic saturated aliphatic hydrocarbon groups such as cyclopentyl and cyclohexyl groups. ３ The monovalent aromatic hydrocarbon group having 6 to 12 carbon atoms constituting the formula (I) is not particularly limited, but examples thereof include aryl groups such as a phenyl group and a naphthyl group; and arylalkyl groups such as a benzyl group and a phenylethyl group.

[0055] In some embodiments, R in formula (2) above ３ In some embodiments, R in the above formula (2) may contain both a hydrogen atom and a linear aliphatic saturated hydrocarbon group, or may contain both a hydrogen atom and a methyl group, taking into consideration the refractive index of the component (B). ３ In some embodiments, R in the above formula (2) may not contain a monovalent aromatic hydrocarbon group having 6 to 12 carbon atoms, taking into consideration the refractive index of the component (B). ３ In consideration of the refractive index of component (A), all groups other than hydrogen atoms may be methyl groups.

[0056] In the above formula (2), R ４ As described above, R is a hydrogen atom or a monovalent hydrocarbon group having 1 to 4 carbon atoms. ４ The monovalent hydrocarbon group having 1 to 4 carbon atoms constituting the formula (I) is not particularly limited, but examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a tert-butyl group, and a sec-butyl group.

[0057] In some embodiments, R in formula (2) above ４ may be a group selected from the group consisting of a hydrogen atom, a methyl group, and an ethyl group, or may be a group selected from the group consisting of a hydrogen atom and a methyl group.

[0058] In the above formula (2), the monofunctional siloxane unit "R ３ (CH ３ ) ２ SiO １／２ The ratio f in " satisfies 0≦f≦1 (in other words, 0 or more and 1 or less). That is, the monofunctional siloxane unit may not be contained in the polysiloxane. In some embodiments, the ratio f may be greater than 0 (0<f), alternatively 0.02 or more, alternatively 0.1 or more, or alternatively 0.3 or more. At the same time, the ratio f may be 0.7 or less, alternatively 0.5 or less. When the ratio f is greater than 0, that is, when the polysiloxane contains a monofunctional siloxane unit, it becomes easier to control the molecular weight. On the other hand, when the ratio f is 0.7 or less, the volatility of the polysiloxane can be reduced.

[0059] In some embodiments, the difunctional siloxane units "R ３ (CH ３ ) SiO ２／２ " satisfies 0≦g≦1 (in other words, 0 or more and 1 or less). That is, the polysiloxane does not need to contain a difunctional siloxane unit. In some embodiments, the ratio g may be 0.98 or less, or 0.9 or less, or 0.85 or less. A ratio g of 0.98 or less makes it easy to design the viscosity of the polysiloxane, component (B), to an appropriate value. As mentioned above, in some embodiments, the polysiloxane does not need to contain a difunctional siloxane unit. On the other hand, when the polysiloxane contains a difunctional siloxane unit, there is an advantage in that flexibility can be imparted to a coating film formed using the polysiloxane composition.

[0060] In the above formula (2), the trifunctional siloxane unit "R ３ SiO ３／２" satisfies 0≦h<1 (in other words, 0 or more and less than 1). That is, trifunctional siloxane units may not be contained in the polysiloxane. In some embodiments, the ratio h may be 0.5 or less, or 0.4 or less, or 0.2 or less. When the ratio h is 0.5 or less, it becomes easy to design the viscosity of the polysiloxane, which is component (B), to an appropriate value. As mentioned above, in some embodiments, the polysiloxane may not contain trifunctional siloxane units. On the other hand, when the polysiloxane contains trifunctional siloxane units, there is an advantage in that rigidity can be imparted to a coating film formed using the polysiloxane composition.

[0061] In the above formula (2), the tetrafunctional siloxane unit "SiO ４／２ " satisfies 0≦i≦0.6 (in other words, 0 or more and 0.6 or less). That is, tetrafunctional siloxane units, like the mono-, di-, and trifunctional siloxane units, may not be contained in the polysiloxane. In some embodiments, the ratio i may be 0.5 or less, or 0.4 or less. A ratio i of 0.6 or less can reduce the brittleness of a coating film formed using the polysiloxane composition. As mentioned above, in some embodiments, the polysiloxane of component (B) does not need to contain tetrafunctional siloxane units. On the other hand, the inclusion of tetrafunctional siloxane units in the polysiloxane has the advantage of increasing the softening point of a coating film formed using the polysiloxane composition.

[0062] In some embodiments, in the above formula (2), 0<h+i may be satisfied. In other words, component (B) may contain both or either a trifunctional siloxane unit and a tetrafunctional siloxane unit. The presence of these siloxane units can impart rigidity to a coating film formed using the polysiloxane composition.

[0063] In the above formula (2), the sum of the ratios f, g, h, and i satisfies f+g+h+i=1.

[0064] In the above formula (2), the remaining reactive group "R ４ O １／２ The ratio j in " satisfies 0≦j≦0.1 (in other words, 0 or more and 0.1 or less). When the ratio j is 0.1 or less, the storage stability of the polysiloxane composition can be improved. In some embodiments, the ratio j may be 0.08 or less, or 0.05 or less.

[0065] As described above, the above formula (2) represents [H(CH3)2SiO 1 / 2 ], [H(CH3)SiO 2 / 2 ], and [HSiO 3 / 2 In some embodiments, formula (2) comprises at least one unit selected from the group consisting of [H(CH3)2SiO 1 / 2 ] and [H(CH3)SiO 2 / 2 ] or [H(CH3)2SiO 1 / 2 ], or [H(CH3)SiO 2 / 2 In some embodiments, in consideration of good reactivity with component (A), formula (2) may contain a monofunctional siloxane unit, [H(CH3)2SiO 1 / 2 ] may be included.

[0066] In some embodiments, the number of silicon-bonded hydrogen atoms (SiH) (average value) contained per molecule of the polysiloxane of component (B) may be 2 or more, alternatively 3 or more, or alternatively 5 or more, and the number of silicon-bonded hydrogen atoms may be 100 or less, alternatively 50 or less, alternatively 30 or less, or alternatively 20 or less.

[0067] Non-limiting examples of component (B) include dimethylpolysiloxane capped at both ends with dimethylhydrogensiloxy groups, polymethylhydrogensiloxane capped at both ends with trimethylsiloxy groups, polymethylhydrogensiloxane capped at both ends with dimethylhydrogensiloxy groups, poly(dimethylsiloxane)(methylhydrogensiloxane) copolymer capped at both ends with trimethylsiloxy groups, poly(dimethylsiloxane)(methylhydrogensiloxane) copolymer capped at both ends with dimethylhydrogensiloxy groups, tris(dimethylhydrogensiloxy)methylsilane, bis(dimethylhydrogensiloxy)diphenylsilane, Examples include dimethylpolysiloxanes terminated at both molecular chain ends with dimethylhydrogensiloxy groups, partially branched polydimethylsiloxanes containing methylsilsesquioxane units (T units) and terminated at both molecular chain ends with dimethylhydrogensiloxy groups, partially branched polydimethylsiloxanes containing silica units (Q units) and terminated at both molecular chain ends with dimethylhydrogensiloxy groups, tetrakis(dimethylhydrogensiloxy)silane, hexa(dimethylhydrogensiloxy)disiloxane, tris(dimethylhydrogensiloxy)phenylsilane, organopolysiloxane resins represented by the following average unit formula, and combinations thereof. ２ SiO １／２ ) ０．６ (SiO ４／２ ) ０．４ (HMe ２ SiO １／２ ) ０．３ (Me ３ SiO １／２ ) ０．３ (SiO ４／２ ) ０．４ (HMe ２ SiO １／２ ) ０．５ (Me ３ SiO １／２ ) ０．１ (SiO ４／２ ) ０．４ (HMe ２ SiO １／２ ) ０．５ (PhSiO ３／２ ) ０．１ (SiO ４／２ )０．４ (HMe ２ SiO １／２ ) ０．６ (PhSiO ３／２ ) ０．４ (HMe ２ SiO １／２ ) ０．７５ (PhSiO ３／２ ) ０．２５ In the above formula, Me is a methyl group and Ph is a phenyl group.

[0068] <<Properties of Component (B)>> The weight-average molecular weight of the polysiloxane that is component (B) is not particularly limited. In some embodiments, the weight-average molecular weight of component (B) is 500 or more, or 1,000 or more. At the same time, the weight-average molecular weight may be 10,000 or less, or 5,000 or less, or 2,000 or less. When the weight-average molecular weight of component (B) is within the above-mentioned range, the compatibility with component (A) is excellent, and the coatability of the polysiloxane composition to a substrate is further improved.

[0069] The polydispersity index (hereinafter sometimes referred to as "PDI") of the polysiloxane of component (B) is not particularly limited. In some embodiments, the polydispersity index of component (B) may be, for example, 1.1 or more and 10 or less. The higher the weight average molecular weight described above, the higher the PDI value tends to be.

[0070] The softening temperature of the polysiloxane of component (B) is not particularly limited. In some embodiments, component (B) may be liquid at 25° C. or may be solid with a glass transition temperature of 30° C. or higher. In consideration of workability, it is preferable that component (B) be liquid at 25° C.

[0071] <<Content of Component (B)>> The amount of component (B) contained in the polysiloxane composition of the present disclosure is not particularly limited, as long as the number of moles of silicon-bonded hydrogen atoms in component (B) per mole of silanol groups in component (A) is 0.2 to 3.0 moles. When this number of moles is within this range, the silicone composition can be used to form a coating film with a low refractive index and excellent solvent resistance. If this number of moles is below this lower limit, heat curing does not occur efficiently, and if it exceeds the upper limit, the excess component (B) adversely affects the solvent resistance of the coating film, which is unsuitable. In some embodiments, the number of moles of silicon-bonded hydrogen atoms in component (B) per mole of silanol groups in component (A) may be 0.5 moles or more, or 0.6 moles or more, and may also be 2.0 moles or less, or less than 1.0 mole.

[0072] <Component (C): Organic Solvent> The organic solvent, component (C), has the function of controlling the coatability of the polysiloxane component, which is a mixture of components (A) and (B) described above, and adjusting the thickness of the coating film.

[0073] <<Types of Component (C)>> The organic solvent usable as component (C) is not particularly limited, and examples thereof include (poly)alkylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol mono-n-butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-propyl ether, diethylene glycol mono-n-butyl ether, propylene glycol monomethyl ether (PGME), propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, propylene glycol mono-n-butyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, and dipropylene glycol mono-n-butyl ether; (Poly)alkylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol methyl ether acetate (PGMEA), and propylene glycol ethyl ether acetate; other ethers such as diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, and cyclopentyl methyl ether; ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, 2-heptanone, 3-heptanone, 4-heptanone, 5-methyl-3-heptanone, 2,4-dimethyl-3-pentanone, and 2,6-dimethyl-4-heptanone; alkyl lactate esters such as methyl 2-hydroxypropionate and ethyl 2-hydroxypropionate;Other esters such as ethyl 2-hydroxy-2-methylpropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutylpropionate, ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, n-pentyl formate, i-pentyl acetate, n-butyl propionate, ethyl butyrate, n-propyl butyrate, i-propyl butyrate, n-butyl butyrate, methyl pyruvate, ethyl pyruvate, n-propyl pyruvate, methyl acetoacetate, ethyl acetoacetate, and ethyl 2-oxobutanoate; alicyclic hydrocarbons such as cyclohexane, methylcyclohexane, ethylcyclohexane, and dimethylcyclohexane; Examples of the organic solvent include aromatic hydrocarbons such as benzene, toluene, ethylbenzene, and xylene; and aromatic ethers such as anisole, phenetole, 2-methoxytoluene, 3-methoxytoluene, 4-methoxytoluene, 3,4-dimethoxytoluene, and 1,4-bis(methoxymethyl)benzene. The organic solvent as component (C) may be used alone or in combination with multiple types, taking into consideration the miscibility with components (A) and (B).

[0074] In some embodiments, from the viewpoint of further improving the coatability of the polysiloxane composition to form a high-quality coating film and reducing safety concerns for living organisms, component (C) may contain an organic solvent selected from the group consisting of propylene glycol alkyl ether compounds and alkylcycloalkane compounds. Non-limiting examples of propylene glycol alkyl ether compounds include, but are not limited to, propylene glycol monomethyl ether (PGME) and propylene glycol methyl ether acetate (PGMEA). Non-limiting examples of alkylcycloalkane compounds include, but are not limited to, methylcyclohexane and ethylcyclohexane.

[0075] In some embodiments, from the viewpoint of further improving the coatability of the polysiloxane composition and forming a high-quality coating film, component (C) may contain methylcyclohexane. In these embodiments, methylcyclohexane alone may be used as component (C), or a mixed solvent of methylcyclohexane with the other solvents described above may be used. Here, the other solvent to be mixed with methylcyclohexane may be a propylene glycol alkyl ether compound such as PGME or PGMEA. In some embodiments, component (C) may be an organic solvent that does not contain benzene, toluene, ethylbenzene, or xylene.

[0076] <<Content of Component (C)>> The amount of component (C) contained in the polysiloxane composition of the present disclosure is not particularly limited. In some embodiments, the amount of component (C) may be 20 parts by mass or more and 5,000 parts by mass or less, where the total mass of components (A) and (B) is 100 parts by mass. When the amount of component (C) is within the above-mentioned range, the storage stability of the polysiloxane composition and good coatability to substrates over a wide range of film thicknesses can be ensured. Furthermore, it becomes easier to control the film thickness of a coating film formed from the polysiloxane composition. In some embodiments, the amount of component (C) contained in the polysiloxane composition may be 50 parts by mass or more, 70 parts by mass or more, or 100 parts by mass or more, where the total mass of components (A) and (B) is 100 parts by mass, from the viewpoint of further improving the storage stability and coatability to substrates of the polysiloxane composition. At the same time, the amount of component (C) may be 1,000 parts by mass or less, 500 parts by mass or less, or 250 parts by mass or less.

[0077] In some embodiments, the amount of component (C) contained in the polysiloxane composition of the present disclosure may be 30% by mass or more, 50% by mass or more, or 60% by mass or more, based on 100% by mass of the total mass of the polysiloxane composition, in order to improve the storage stability and coatability of the polysiloxane composition to a substrate. At the same time, the amount of component (C) may be 85% by mass or less, 75% by mass or less, or 70% by mass or less. In some embodiments, the polysiloxane composition may contain a small amount of at least one of benzene, toluene, ethylbenzene, and xylene as an organic solvent corresponding to component (C). However, in some embodiments, in order to further improve safety to living organisms, the total amount of benzene, toluene, ethylbenzene, and xylene contained in the polysiloxane composition of the present disclosure may be 1% by mass or less, 0.1% by mass or less, 0.05% by mass or less, 0.01% by mass or less, or 0% by mass (below the detection limit), based on 100% by mass of the total mass of the polysiloxane composition.

[0078] <Other Components> The polysiloxane composition of the present disclosure may contain other components in addition to the above-described component (A), component (B), and component (C).

[0079] In addition to the above-described components, the polysiloxane composition of the present disclosure may also contain a platinum-based compound as component (D), which has the effect of accelerating the chemical reaction between components (A) and (B).

[0080] The content of component (D) is an amount that promotes curing of the polysiloxane composition and is not particularly limited. In some embodiments, the content of component (D) in the polysiloxane composition may be an amount such that the platinum atoms in the platinum-based compound are within a range of 0.1 to 1,000 ppm by mass, based on the polysiloxane composition excluding component (C). When the content of component (D) is equal to or greater than the lower limit of the above range, curing of the polysiloxane composition is sufficiently promoted, whereas when the content is equal to or less than the upper limit of the above range, the coating film obtained from the polysiloxane composition is less likely to be colored.

[0081] In some embodiments, component (D) may be selected from the group consisting of: (d1) a platinum-based compound that exhibits activity without high-energy radiation, (d2) a platinum-based compound that exhibits activity upon high-energy radiation, and (d3) a platinum-based compound that is a combination of components (d1) and (d2), or only (d1) may be used.

[0082] Component (d1) is a compound that exhibits activity without high-energy radiation and promotes the chemical reaction of components (A) and (B) to promote the curing of the polysiloxane composition. Non-limiting examples of this platinum-based compound include platinum fine powder, platinum black, platinum-supported silica fine powder, platinum-supported activated carbon, chloroplatinic acid, alcohol solutions of chloroplatinic acid, platinum olefin complexes, platinum alkenylsiloxane complexes, and combinations thereof. In some embodiments, platinum alkenylsiloxane complexes may be used as component (d1). Non-limiting examples of the alkenylsiloxane include 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, alkenylsiloxanes in which a portion of the methyl groups of these alkenylsiloxanes have been substituted with ethyl groups and / or phenyl groups, etc., alkenylsiloxanes in which the vinyl groups of these alkenylsiloxanes have been substituted with allyl groups and / or hexenyl groups, etc., and combinations thereof. In some embodiments, 1,3-divinyl-1,1,3,3-tetramethyldisiloxane may be used as the alkenylsiloxane because it improves the stability of the platinum alkenylsiloxane complex. In some embodiments, from the viewpoint of improving the stability of the platinum-alkenylsiloxane complex, an alkenylsiloxane such as 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, 1,3-diallyl-1,1,3,3-tetramethyldisiloxane, 1,3-divinyl-1,3-dimethyl-1,3-diphenyldisiloxane, 1,3-divinyl-1,1,3,3-tetraphenyldisiloxane, or 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, or an organosiloxane oligomer such as a dimethylsiloxane oligomer, or an alkenylsiloxane may be added to the complex.

[0083] In some embodiments, component (d1) may be a compound that exhibits activity even at relatively low temperatures. For example, component (d1) may be a compound that exhibits activity in the composition in a temperature range of 0 to 200°C, or a temperature range of 0 to 150°C, or a temperature range of 10 to 150°C, or a temperature range of 20 to 150°C, and promotes the chemical reaction of components (A) and (B). The content of component (d1) varies depending on the type of compound and the type of composition. In some embodiments, the content of component (d1) may be an amount such that the metal atoms in this compound are in the range of 0.1 to 50 ppm by mass, or in the range of 0.1 to 30 ppm by mass, relative to the polysiloxane composition. A content of this component of 0.1 ppm by mass or more provides a sufficient curing reaction-accelerating effect, while a content of 50 ppm by mass or less eliminates concerns about coloration of the cured product obtained by the curing reaction and is economical.

[0084] Component (d2) is a platinum-based compound that exhibits little activity in the absence of high-energy radiation, but exhibits activity upon exposure to high-energy radiation. Component (d2) is a so-called high-energy radiation-activated catalyst or photoactivated catalyst, and is well known in the art.

[0085] Examples of high-energy rays include ultraviolet rays, visible light, gamma rays, X-rays, α-rays, and electron beams. In some embodiments, the high-energy rays are ultraviolet rays, visible light, X-rays, electron beams irradiated from a commercially available electron beam irradiation device, and combinations thereof. In some embodiments, ultraviolet rays, visible light, and combinations thereof may be used from the viewpoint of compound activation efficiency. In some embodiments, ultraviolet rays, visible light, and combinations thereof with wavelengths in the range of 280 to 405 nm may be used from the viewpoint of industrial application. The irradiation dose varies depending on the type of high-energy ray-activated compound, but in the case of ultraviolet rays, the cumulative irradiation dose at a wavelength of 365 nm is 100 mJ / cm. ２ ~10 J / cm ２ may be in the range of

[0086] Non-limiting examples of component (d2) include (methylcyclopentadienyl)trimethylplatinum(IV), (cyclopentadienyl)trimethylplatinum(IV), (1,2,3,4,5-pentamethylcyclopentadienyl)trimethylplatinum(IV), (cyclopentadienyl)dimethylethylplatinum(IV), (cyclopentadienyl)dimethylacetylplatinum(IV), (trimethylsilylcyclopentadienyl)trimethylplatinum(IV), (methoxycarbonylcyclopentadienyl)trimethylplatinum(IV), (dimethylphenylsilylcyclopentadienyl)trimethylcyclopentadienylplatinum(IV), trimethylsilylcyclopentadienyl Examples of suitable platinum complexes include trimethyl(acetylacetonato)platinum(IV), trimethyl(3,5-heptanedionato)platinum(IV), trimethyl(methylacetoacetate)platinum(IV), bis(2,4-pentanedionato)platinum(II), bis(2,4-hexanedionato)platinum(II), bis(2,4-heptanedionato)platinum(II), bis(3,5-heptanedionato)platinum(II), bis(1-phenyl-1,3-butanedionato)platinum(II), bis(1,3-diphenyl-1,3-propanedionato)platinum(II), bis(hexafluoroacetylacetonato)platinum(II), and combinations thereof. In some embodiments, in view of versatility and ease of availability, component (d2) may be (methylcyclopentadienyl)trimethylplatinum(IV), bis(2,4-pentanedionato)platinum(II), and combinations thereof.

[0087] In some embodiments, the content of component (d2) may be an amount such that the metal atoms in this compound are in the range of 0 to 100 ppm by mass, or in the range of 0 to 50 ppm by mass, relative to the polysiloxane composition excluding component (C).

[0088] In some embodiments, the polysiloxane composition may contain components (A) to (C) but not contain the platinum-based compound that is component (D). In some embodiments, the polysiloxane composition may contain components (A) to (C) but not contain the condensation reaction catalyst.

[0089] In some embodiments, the polysiloxane composition may optionally include additional additives as component (E), including, but not limited to, the following:

[0090] <<Adhesion Imparting Agent>> In some embodiments, the polysiloxane composition may contain an adhesion imparting agent to improve adhesion to a substrate. When the polysiloxane composition of the present disclosure is used for applications requiring adhesion to a substrate, such as a coating agent or a sealant, an adhesion imparting agent may be added to the composition. As this adhesion imparting agent, any known adhesion imparting agent can be used as long as it does not interfere with the step of removing component (C) from the polysiloxane composition of the present disclosure. Note that one type of adhesion imparting agent may be used alone, or multiple types may be used in combination.

[0091] Non-limiting examples of adhesion promoters include: organosilanes having a trialkoxysiloxy group (e.g., trimethoxysiloxy group, triethoxysiloxy group) and / or a trialkoxysilylalkyl group (e.g., trimethoxysilylethyl group, triethoxysilylethyl group), and a hydrosilyl group and / or an alkenyl group (e.g., vinyl group, allyl group); organosiloxane oligomers having a linear, branched or cyclic structure and about 4 to 20 silicon atoms, and having a trialkoxysiloxy group and / or a trialkoxysilylalkyl group, and a hydrosilyl group and / or an alkenyl group; organosilanes having a trialkoxysiloxy group and / or a trialkoxysilylalkyl group, and a methacryloxyalkyl group (e.g., 3-methacryloxypropyl group); Organosiloxane oligomers having a linear, branched, or cyclic structure and having about 4 to 20 silicon atoms, which have a trialkoxysiloxy group and / or a trialkoxysilylalkyl group and a methacryloxyalkyl group; organosilanes having a trialkoxysiloxy group and / or a trialkoxysilylalkyl group and an epoxy group-bonded alkyl group (e.g., 3-glycidoxypropyl group, 4-glycidoxybutyl group, 2-(3,4-epoxycyclohexyl)ethyl group, 3-(3,4-epoxycyclohexyl)propyl group); organosiloxane oligomers having a linear, branched, or cyclic structure and having about 4 to 20 silicon atoms, which have a trialkoxysiloxy group and / or a trialkoxysilylalkyl group and an epoxy group-bonded alkyl group; organic compounds having two or more trialkoxysilyl groups (e.g., trimethoxysilyl group, triethoxysilyl group); reaction products of aminoalkyltrialkoxysilanes and epoxy group-bonded alkyltrialkoxysilanes; epoxy group-containing ethyl polysilicate; and combinations thereof.

[0092] Further non-limiting examples of adhesion promoters include vinyltrimethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, hydrogentriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 1,6-bis(trimethoxysilyl)hexane, 1,6-bis(triethoxy ... , 3-bis[2-(trimethoxysilyl)ethyl]-1,1,3,3-tetramethyldisiloxane, a reaction product of 3-glycidoxypropyltriethoxysilane and 3-aminopropyltriethoxysilane, a condensation reaction product of a silanol group-blocked methylvinylsiloxane oligomer and 3-glycidoxypropyltrimethoxysilane, a condensation reaction product of a silanol group-blocked methylvinylsiloxane oligomer and 3-methacryloxypropyltriethoxysilane, tris(3-trimethoxysilylpropyl)isocyanurate, and combinations thereof.

[0093] In some embodiments, from the viewpoint of suppressing discoloration of the solid material obtained from the polysiloxane composition while sufficiently exhibiting adhesiveness, the amount of the adhesion promoter may be 0.01 parts by mass or more, and may be 5 parts by mass or less, or 2 parts by mass or less, per 100 parts by mass of component (A).

[0094] <<Other Additives>> In some embodiments, other additives may be added to the polysiloxane composition as desired, in addition to or instead of the adhesion promoter described above. Examples of other additives include, but are not limited to, leveling agents, wettability improvers, silane coupling agents not included in the adhesion promoters described above, high-energy ray absorbers, antioxidants, polymerization inhibitors, fillers (functional fillers such as reinforcing fillers, insulating fillers, hollow fillers, and thermally conductive fillers), and thixotropy-imparting agents. These additives may be used alone or in combination. Thixotropy-imparting agents are particularly useful when the polysiloxane composition of the present disclosure is used as a sealant.

[0095] <Method for Preparing Polysiloxane Composition> The method for preparing the polysiloxane composition of the present disclosure is not particularly limited. For example, the polysiloxane composition of the present disclosure can be prepared by mixing components (A), (B), and (C), as well as other components used as needed, using a known method.

[0096] (Uses of Polysiloxane Composition) The uses of the polysiloxane composition of the present disclosure are not particularly limited. In some embodiments, the polysiloxane composition may be used as an insulating coating agent, or the polysiloxane composition may be used to form an insulating coating. In some embodiments, a display device may include a layer made of a solid material formed using the polysiloxane composition of the present disclosure.

[0097] When using the polysiloxane composition of the present disclosure for various applications, a processing method thereof will be described. In some embodiments, the processing method of the polysiloxane composition (e.g., a method for producing an insulating coating) includes at least a step of removing component (C) from the polysiloxane composition to obtain a dried product (hereinafter referred to as the "organic solvent removal step"), and a step of heating the obtained dried product at a temperature of 150°C or higher to react component (A) and component (B) (hereinafter referred to as the "reaction step"). Note that the processing method may also include a step of applying the polysiloxane composition to a substrate (hereinafter referred to as the "application step") prior to the organic solvent removal step.

[0098] In the coating step, the method for coating the polysiloxane composition onto the substrate is not particularly limited, and known methods using coating devices such as spin coaters, roll coaters, bar coaters, and slit coaters can be used. The type of substrate is also not particularly limited, and known substrates such as silicon wafers can be used depending on the intended use of the polysiloxane composition. In the organic solvent removal step, the method for removing component (C) from the polysiloxane composition is not particularly limited. In some embodiments, component (C) can be removed by drying with heat. By heating the polysiloxane composition coated on the substrate, the organic solvent component (C) is dried and removed, and a solid such as a coating film can be obtained. The heating method and conditions are not particularly limited, and examples include drying on a hot plate or in an oven at a temperature of 80 to 150°C or 90 to 110°C for 1 to 5 minutes; leaving it at room temperature for several hours; and heating in a hot air heater or infrared heater for several tens of minutes to several hours. In the reaction step, the polysiloxane composition from which component (C) has been removed is heated for a certain period of time at a temperature higher than that used in the organic solvent removal step to react the silanol groups in component (A) with the silicon-bonded hydrogen atoms in component (B). The heating temperature may be 150°C or higher, 180°C or higher, or 200°C or higher. The heating time may be 5 minutes or longer, or 10 minutes or longer. Separating the organic solvent removal step and the reaction step by changing the temperature can improve the reaction efficiency and the quality of solids such as coating films. The processing method for the polysiloxane composition is not limited to the above. In some embodiments, the organic solvent removal step may be performed at a temperature of about 150°C, and the heating time may be extended to simultaneously perform the organic solvent removal step and the reaction step.

[0099] Through such a process, a solid material with an increased specific gravity can be obtained, and the solid material can be used for any purpose, such as an insulating coating.

[0100] In the present disclosure, the viscosity of the polysiloxane composition and / or the rate of production of a solid formed using the polysiloxane composition can be controlled by changing the structure, boiling point, and / or amount of the organic solvent used as component (C). Furthermore, in the present disclosure, the molecular structure of the branched polysiloxane used as component (A) and / or the ratio of remaining reactive groups can be changed to design the solid to have the desired refractive index and mechanical properties. The shape of the solid (branched polysiloxane solid) obtained by removing component (C) from the polysiloxane composition, which is one embodiment of the present disclosure, is not particularly limited and may be a thin-film coating or a molded product such as a sheet. In some embodiments, the solid may be used as a sealant or intermediate layer for laminates or display devices. In some embodiments, the solid may be in the form of a thin-film coating or a thin-film insulating coating. Such insulating coatings are particularly useful, for example, as materials for forming insulating layers in electronic and electrical devices.

[0101] Furthermore, since the solid formed using the polysiloxane composition of the present disclosure has good transparency, an insulating coating made of the solid is suitable as a material for forming an insulating layer in a display device such as a touch panel or a display. In this case, the insulating layer may be formed into any desired pattern as needed. Therefore, a display device such as a touch panel or a display, which includes an insulating layer made of a solid formed using the polysiloxane composition of the present disclosure, can also be cited as an embodiment of the present disclosure.

[0102] In some embodiments, the refractive index of a solid (coating) formed using the polysiloxane composition at a wavelength of 633 nm may be less than 1.45, or 1.44 or less, or 1.43 or less, or 1.42 or less. The refractive index of the solid can be controlled, for example, by the type of substituent on the silicon atom in component (A) and / or (B) and the ratio of various siloxane units and OZ groups. More specifically, the refractive index of the solid can be lowered by reducing the ratio of trifunctional siloxane units and increasing the ratio of monofunctional siloxane units in component (A) and / or (B).

[0103] The polysiloxane composition of the present disclosure will be further described below based on examples, but the present disclosure is not limited to the following examples. The following methods were used for various measurements and evaluations.

[0104] <Appearance of Coating Film> The coating film obtained from the polysiloxane composition was visually observed, and the appearance including transparency was evaluated.

[0105] <Average unit formulas of components (A) and (B), and SiOH and SiH contents> １３ C-NMR and ２９ The molar concentrations of each siloxane unit and silanol group were calculated by Si-NMR spectroscopy, and the average unit formula, as well as the content of silanol groups (SiOH) and silicon-bonded hydrogen atoms (SiH), were identified.

[0106] <Molecular Weight and PDI of Components (A) and (B)> Gel permeation chromatography (GPC) analysis was performed using tetrahydrofuran as an eluent to measure the weight average molecular weight (Mw) and number average molecular weight (Mn) in terms of standard polystyrene. From these values, the PDI (Mw / Mn) was calculated.

[0107] <Coating Properties of Polysiloxane Composition> The prepared polysiloxane composition was spin-coated onto a silicon wafer substrate to a thickness of 4 μm. The polysiloxane composition on the substrate was heated in an oven at 100°C for 5 minutes to remove component (C) and obtain a dried product. The polysiloxane composition was further heated at 150°C or 200°C (the temperatures used in each Example and Comparative Example are shown in Table 1) for 10 minutes to form a coating film (cured coating film). This coating film was inspected and evaluated according to the following criteria: A: No coating unevenness, coating thickness uniform; B: Coating unevenness observed in parts (5% or less of the total coating area), but the coating thickness was approximately uniform enough to cause no problems in practical use; C: Coating unevenness observed over a wide area (more than 5% of the total coating area), causing problems in practical use.

[0108] <Reaction Rate of Component (B)> In the same manner as in "Coatability of Polysiloxane Composition," a dried product and a coating film (cured coating film) were formed, and each was analyzed by infrared absorption spectroscopy. The infrared absorption spectroscopy was measured by total reflection spectroscopy using an FT-IR analyzer (manufactured by Nicolet, product name "iS50"). Based on the results of this analysis, the reduction rate of silicon-bonded hydrogen atoms (SiH) in component (B) was calculated using the following formula. The reaction rate of component (B) was then evaluated according to the following criteria: -Reduction Rate of SiH- Reduction Rate of SiH=100×[(X ０ -X １ ) / (X ０ ) ] In the above formula, X ０ is the [I ２１４０ ] / [I １２６８ ] and X １ is the [I ２１４０ ] / [I １２６８ ]. Note that [I ２１４０ ] is the sample's 2140 cm －１ is the absorbance at [I １２６８ ] is the sample's 1268 cm －１ - Evaluation criteria for reaction rate - A: SiH reduction rate is 99% or more and 100% or less (almost quantitative) B: SiH reduction rate is 80% or more and less than 99% C: SiH reduction rate is less than 80%

[0109] <Solvent resistance of coating film> A coating film (cured coating film) was formed in the same manner as in "Coating property of polysiloxane composition." The silicon wafer with the obtained coating film was immersed in PGMEA for 1 minute, and the appearance of the coating film was evaluated according to the following criteria: A: No change in appearance B: Slight damage (blistering, peeling) on ​​the surface C: Partial dissolution

[0110] <Refractive index of coating film> A coating film (cured coating film) was formed in the same manner as in "Coating property of polysiloxane composition." The refractive index of this coating film at a wavelength of 633 nm was measured under the following conditions. Measuring device: film thickness / refractometer "Model 2010 / M Prism Coupler" (manufactured by Metricon) Measurement temperature: room temperature (25°C)

[0111] Synthesis Example 1: Branched Polysiloxane (A-1) A 500 mL three-neck flask equipped with a thermometer, a stirrer, and a nitrogen inlet tube was charged with 118.3 g of methyltrimethoxysilane and 30.0 g of hexamethyldisiloxane as starting materials, 2.1 g of a 1 mol / L aqueous solution of hydrochloric acid as an acid catalyst, 48 g of water, and 222.4 g of methylcyclohexane as a reaction solvent. This mixture was refluxed at 60°C for 2 hours using a mantle heater to carry out a hydrolysis and condensation reaction. After the resulting reaction solution was cooled to below 40°C, 0.57 g of a 34% by weight aqueous solution of potassium hydroxide as a basic catalyst was added to the reaction solution and stirred for 30 minutes. The set temperature was then raised to 90°C, and methanol and excess water were removed from the reaction solution as an azeotrope with methylcyclohexane. After the reaction solution reached 90°C, it was stirred for an additional 1 hour. After the reaction solution was cooled to 60°C or below, 4 g of an adsorbent (Kyowa Chemical Industry Co., Ltd., "Kyoward (registered trademark) 700PL") was added and the mixture was stirred at the same temperature for 30 minutes. The solid was filtered off and the volatile components were distilled off under reduced pressure to obtain a colorless methylcyclohexane solution of branched polysiloxane (A-1). The obtained branched polysiloxane (A-1) was １３ C and ２９The obtained branched polysiloxane (A-1) was analyzed by SiNMR spectroscopy and gel permeation chromatography (GPC). As a result, it was confirmed that the obtained branched polysiloxane (A-1) was a poly(trimethylsiloxane / methylsiloxane) copolymer with a molar ratio of trimethylsilyl groups / methylsilyl groups of 20 / 80. Furthermore, the amount of OZ groups was 0.075 mol per mole of silicon atoms, and the content of silanol groups was 0.075 mol per mole of silicon atoms. The Mw was 113,500, and the PDI was 21.

[0112] From the above results, A-1 has the following average unit formula (1): a = 0.2, b = 0, c = 0.8, d = 0, e1 = 0.075, e2 = 0, R １ = methyl group (R ２ It was found to have the following average unit formula: [(CH3)3SiO 1／2 ] 0.2 [(CH3)SiO 3／2 ] 0.8 [HO 1／2 ] 0.075

[0113] Examples 1 to 6 and Comparative Examples 1 to 3 Polysiloxane compositions were prepared by mixing (A) a branched polysiloxane, (B) a polysiloxane having two or more silicon-bonded hydrogen atoms, (C) an organic solvent, and, if necessary, (D) a platinum-based compound in amounts of parts by mass shown in Table 1. Coating films (solids) were formed from the polysiloxane compositions, and various evaluations were carried out for the above-mentioned items. All results are shown in Table 1. Note that the parts by mass in Table 1 refer to the solid content of all components other than (C) the organic solvent.

[0114] The components (structure and properties) in Table 1 are as follows: (A-1) Branched polysiloxane obtained in Synthesis Example 1 (A-2) Branched polysiloxane (powdered resin) obtained by removing the toluene dispersant from "DOWSIL (registered trademark) SR 2400" manufactured by The Dow Chemical Company under reduced pressure. Mw: 6,000 PDI: 2.5 Average unit formula: [(CH3)2SiO 2 / 2 ] 0.14 [(CH3)SiO 3 / 2 ] 0.86 [HO1 / 2 ] 0.09 In the average unit formula (1), a = 0, b = 0.14, c = 0.86, d = 0, e1 = 0.09, e2 = 0, R １ = methyl group (R ２ (B-1) Silicon-bonded hydrogen-functional branched polysiloxane. Silicon-bonded hydrogen atom content: 0.96% by mass. Mw: 1,000. PDI: 1.1. Average unit formula: [(CH)HSiO 1 / 2 ] 0.64 [SiO 4 / 2 ] 0.36 [(CH3)O 1 / 2 ] 0.02 In the average unit formula (2), f = 0.64, g = 0, h = 0, i = 0.36, j = 0.02, R ３ = hydrogen atom, R ４ = methyl group. (B-2) Silicon-bonded hydrogen-functional linear polysiloxane Silicon-bonded hydrogen atom content: 0.70 mass% Mw: 4,000 PDI: 2.1 Average unit formula: [(CH3)3SiO 1 / 2 ] 0.02 [H(CH3)SiO 2 / 2 ] 0.49 [(CH3)2SiO 2 / 2 ] 0.49 In the average unit formula (2), f = 0.02, g = 0.98 (0.49 + 0.49), h = 0, i = 0, j = 0, R ３ = methyl group or hydrogen atom (R ４ (C-1) Methylcyclohexane (MCH) (D-1) Platinum 1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex MCH solution with a platinum content of 0.02% by mass: 1% by mass of platinum complex, 99% by mass of MCH)

[0115] In Table 1, [SiH] / [SiOH] means the number of moles of silicon-bonded hydrogen atoms in component (B) per mole of silanol groups in component (A).

[0116]

[0117] The polysiloxane compositions of Examples 1 to 6 exhibited excellent coatability on silicon wafers and were able to form uniform coating films. In particular, the coating films obtained from the compositions containing component (B) having a monofunctional siloxane unit and a tetrafunctional siloxane unit exhibited exceptionally uniform coating thickness. Furthermore, the coating films obtained from the polysiloxane compositions of Examples 1 to 6 exhibited excellent solvent resistance. In particular, the coating films obtained from the compositions containing component (B) having a monofunctional siloxane unit and a tetrafunctional siloxane unit (Examples 1, 3, 5, and 6) and the coating film obtained from the composition containing a platinum-based compound, despite the different structure of component (B), exhibited excellent solvent resistance (Example 4). It is believed that this excellent solvent resistance correlates well with the high reactivity of component (B). Furthermore, the coating films obtained from the polysiloxane compositions of Examples 1 to 6 exhibited low refractive indices. Additionally, all of the coating films obtained from the polysiloxane compositions of Examples 1 to 6 exhibited excellent transparency. On the other hand, it was confirmed that the coating film obtained from the polysiloxane composition of Comparative Example 1, which did not contain component (B), had poor solvent resistance. Also, the coating film obtained from the polysiloxane composition of Comparative Example 2, which did not contain component (A), had poor solvent resistance, and the coating film obtained from the polysiloxane composition of Comparative Example 3, which also did not contain component (A), had poor coatability.

[0118] According to some embodiments of the present disclosure, it is possible to provide a polysiloxane composition capable of forming a coating film having a low refractive index and excellent solvent resistance, and having excellent applicability to a substrate, and uses thereof. Furthermore, the coating film formed using the polysiloxane composition of the present disclosure is of high quality and transparent. Therefore, the polysiloxane composition of the present disclosure is useful as an insulating material for electric and electronic devices such as display devices. The polysiloxane composition of the present disclosure is also useful as an insulating coating agent, an anti-reflective coating material, and the like.

Claims

1. (A) The following average unit formula (1): (In formula (1), R １ are each independently a hydrogen atom, a monovalent aliphatic hydrocarbon group having from 1 to 6 carbon atoms, or a monovalent aromatic hydrocarbon group having from 6 to 12 carbon atoms; R ２ is a monovalent hydrocarbon group having 1 to 4 carbon atoms, and a, b, c, d, e1, and e2 are numbers that satisfy the following conditions: 0≦a≦0.4; 0≦b≦0.5; 0.4≦c<1; 0≦d≦0.6; 0<e1≦0.3; 0≦e2<0.3; 0.03≦e1+e2≦0.3; a+b>0; a+b+c+d=1; (B) a branched polysiloxane represented by the following average unit formula (2): (In formula (2), R ３ are each independently a hydrogen atom, a monovalent aliphatic hydrocarbon group having from 1 to 6 carbon atoms, or a monovalent aromatic hydrocarbon group having from 6 to 12 carbon atoms, provided that formula (2) is [H(CH3)2SiO 1 / 2 ], [H(CH3)SiO 2 / 2 ], and [HSiO 3 / 2 and R ４ is a hydrogen atom or a monovalent hydrocarbon group having from 1 to 4 carbon atoms, and f, g, h, i, and j are numbers that satisfy the following conditions: 0≦f≦1; 0≦g≦1; 0≦h<1; 0≦i≦0.6; 0≦j≦0.1; f+g+h+i=1; and (C) an organic solvent, wherein the content of component (B) is such that the number of moles of silicon-bonded hydrogen atoms in component (B) per mole of silanol groups in component (A) is 0.2 to 3.0 moles.

2. R in the average unit formula (1) １ The polysiloxane composition according to claim 1 , wherein the methyl group is contained and the monovalent aromatic hydrocarbon group having 6 to 12 carbon atoms is not contained.

3. The polysiloxane composition according to claim 1, wherein in the average unit formula (2), 0<f.

4. The polysiloxane composition according to claim 1, wherein in the average unit formula (2), 0<h+i.

5. The polysiloxane composition according to claim 1, wherein the weight average molecular weight of component (A) is 50,000 to 500,000.

6. The polysiloxane composition according to claim 1, wherein d is 0 in the average unit formula (1).

7. The polysiloxane composition of claim 1, wherein component (C) is an organic solvent that does not contain benzene, toluene, ethylbenzene, or xylene.

8. The polysiloxane composition of claim 1, further comprising (D) a platinum-based compound.

9. The polysiloxane composition according to claim 1, wherein the content of component (C) is 20 to 5,000 parts by mass per 100 parts by mass of the total mass of components (A) and (B).

10. The polysiloxane composition according to claim 1, wherein the content of component (B) is such that the number of moles of silicon-bonded hydrogen atoms in component (B) per mole of silanol groups in component (A) is 0.2 moles or more but less than 1.0 mole.

11. An insulating coating agent comprising the polysiloxane composition according to any one of claims 1 to 10.

12. An insulating coating formed using the polysiloxane composition according to any one of claims 1 to 10.

13. A method for producing an insulating coating, comprising the steps of removing component (C) from the polysiloxane composition according to any one of claims 1 to 10 to obtain a dried product, and heating the dried product at a temperature of 150°C or higher to react component (A) with component (B).

14. A display device comprising a layer made of a solid material formed using the polysiloxane composition according to any one of claims 1 to 10.

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