JP2021172707A - Organopolysiloxane, composition containing the organopolysiloxane, production method therefor, coating agent, and coated article - Google Patents

Abstract

To provide an organopolysiloxane that can form a composition that can give a cured coat having low-temperature quick curability, crack resistance and solvent resistance and having high hardness, and a composition containing the organopolysiloxane.SOLUTION: An organopolysiloxane has a structure represented by the following average formula (I) (where R1 is a hydrogen atom or an alkyl, aralkyl, or aryl group; R2 is a hydrogen atom or a methyl, ethyl, n-propyl, i-propyl, or acetyl group; a, b, c, and d are numbers satisfying 0≤a<1, 0<b≤1, 0≤c<1, 0≤d<1, a+b+c+d=1; and e is a number satisfying 0<e≤4) and has a predetermined peak top and peak area in a specific molecular weight region in a weight average molecular weight distribution by GPC.SELECTED DRAWING: None

Description

The present invention relates to an organopolysiloxane, a composition containing the organopolysiloxane, a method for producing the same, a coating agent, and a coated article.

Organopolysiloxanes containing alkoxysilyl groups are widely used in paints and coatings. Generally, an organopolysiloxane having an alkoxy group at the terminal is mixed with a curing catalyst, and when external energy such as thermal energy is applied, the alkoxy groups at the terminal react with each other to form a strong siloxane network. Since the resulting coating has excellent heat resistance and weather resistance, its construction targets range from outdoor buildings to automobile parts and electronic parts.

Organopolysiloxanes containing an alkoxysilyl group are generally produced by hydrolyzing and condensing alkoxysilanes (Patent Documents 1 and 2).
However, in general, most of the highly active alkoxy groups are consumed by the hydrolysis condensation reaction during production, and only a small number of low-activity alkoxy groups remain in the product organopolysiloxane, and the coating thereof. Is often inferior in curability. The tendency of decrease in curability becomes more remarkable as the molecular weight of the product organopolysiloxane is higher, and additional steps such as heating at a high temperature are required at the time of film formation in order to compensate for the low curability.

On the other hand, in the small molecule organopolysiloxane having a molecular weight of 3,000 or less, since many active alkoxy groups remain, the reactivity is excellent. Therefore, in the composition containing the small molecule organopolysiloxane, heating is performed. Some cure without going through the process. However, since the cured film of low-molecular-weight organopolysiloxane is a thin film, it has low mechanical properties, and when heat is applied from the outside, the residual alkoxy groups in the film react sequentially, causing cracks over time. Have a problem.

As described above, in various organopolysiloxanes, when the molecular weight is large, there are problems such as deterioration of adhesion due to a small number of polymerizable functional groups, low hardness and low scratch resistance, and when the molecular weight is small. Has low mechanical strength and has problems such as cracks occurring over time.
In addition, various physical properties such as curing temperature, heat resistance, light resistance, solvent resistance, surface hardness, and workability of the coating film differ depending on the difference in the molecular weight of the organopolysiloxane. Therefore, a molecular weight suitable for the application is required. There is.
For these reasons, control of the molecular weight of organopolysiloxane is an important factor in the production of organopolysiloxane.
Prior art documents related to the present invention include the following in addition to the above.

Japanese Unexamined Patent Publication No. 2016-108472 Japanese Unexamined Patent Publication No. 2005-8755 International Publication No. 2020/036074

The present invention has been made in view of the above circumstances, and is an organopolysiloxane or an organopolysiloxane capable of forming a composition which is excellent in low temperature rapid curing property, crack resistance and solvent resistance and can give a cured film having high hardness. It is an object of the present invention to provide a composition, a method for producing the same, a coating agent, and a coated article.

As a result of diligent studies to achieve the above object, the present inventors have found an organopoly having a predetermined peak top and peak area in a specific molecular weight region in the weight average molecular weight (Mw) distribution in gel permeation chromatography. We have found that siloxane can solve the above problems, and completed the present invention.

（式中、Ｒ¹は、それぞれ独立に、水素原子、またはハロゲン原子で置換されていてもよい、炭素原子数１〜８のアルキル基、アラルキル基もしくはアリール基を表し、Ｒ²は、水素原子、メチル基、エチル基、ｎ−プロピル基、ｉ−プロピル基またはアセチル基を表す。ａ、ｂ、ｃおよびｄは、それぞれ０≦ａ＜１、０＜ｂ≦１、０≦ｃ＜１、０≦ｄ＜１、ａ＋ｂ＋ｃ＋ｄ＝１を満たす数であり、ｅは０＜ｅ≦４を満たす数である。）
で表される構造を有し、
ゲル浸透クロマトグラフィーにおけるポリスチレン換算の重量平均分子量（Ｍｗ）分布において、Ｍｗが３，０００以上の領域をＭｗ１、Ｍｗが１，０００以下の領域をＭｗ３としたとき、Ｍｗ１およびＭｗ３にそれぞれ１個以上のピークトップを有し、Ｍｗ１全領域のピーク面積ＳＭｗ１を１としたとき、Ｍｗ３全量域のピーク面積ＳＭｗ３の値が０．５〜２．０であるオルガノポリシロキサン、
２． １記載のオルガノポリシロキサンおよび比誘電率が７．０以上９．０以下の溶剤１０質量％以上を含有する組成物、
３． 比誘電率が７．０以上９．０以下の溶剤が、下記一般式（ＩＩ）で表される化合物を含む２記載の組成物、

〔式中、Ｒ³は、炭素原子数１〜４のアルキル基、Ｒ⁴は、直鎖状または分岐状の炭素原子数１〜４のアルキレン基、Ｒ⁵は、炭素原子数１〜４のアルキル基または下記式

（Ｒ³は上記と同じである。）
で表される基である。ｍは１〜３の整数を表す。〕
４． さらに、硬化触媒を含有し、硬化性組成物である２または３記載の組成物、
５． ２〜４のいずれかに記載の組成物からなるコーティング剤、
６． ５記載のコーティング剤の硬化膜、
７． 基材と、該基材の少なくとも一方の面に、直接または１種以上の他の層を介して形成された６記載の硬化膜とを有する被覆物品、
８． 加水分解性基を有するシラン化合物を、比誘電率が７．０以上９．０以下の溶剤を含まない環境で加水分解縮合させて、上記平均式（Ｉ）で表される構造を有するオルガノポリシロキサンを合成した後、比誘電率が７．０以上９．０以下の溶剤を加える工程を含む、２〜４のいずれかに記載の組成物の製造方法
を提供する。 That is, the present invention
1. 1. The following average formula (I)

(In the formula, R ¹ represents an alkyl group, an aralkyl group or an aryl group having 1 to 8 carbon atoms, which may be independently substituted with a hydrogen atom or a halogen atom, respectively, and R ² is a hydrogen atom. , Methyl group, ethyl group, n-propyl group, i-propyl group or acetyl group. A, b, c and d are 0 ≦ a <1, 0 <b ≦ 1, 0 ≦ c <1, respectively. It is a number that satisfies 0 ≦ d <1, a + b + c + d = 1, and e is a number that satisfies 0 <e ≦ 4.)
Has a structure represented by
In the polystyrene-equivalent weight average molecular weight (Mw) distribution in gel permeation chromatography, when the region with Mw of 3,000 or more is Mw1 and the region with Mw of 1,000 or less is Mw3, one or more in Mw1 and Mw3, respectively. Organopolysiloxane, which has a peak top of Mw1 and has a peak area SMw1 of the entire Mw1 region as 1, and a value of the peak area SMw3 of the entire Mw3 region is 0.5 to 2.0.
2. 1. A composition containing 10% by mass or more of the organopolysiloxane and a solvent having a relative permittivity of 7.0 or more and 9.0 or less.
3. 3. 2. The composition according to 2, wherein the solvent having a relative permittivity of 7.0 or more and 9.0 or less contains a compound represented by the following general formula (II).

[In the formula, R ³ is an alkyl group having 1 to 4 carbon atoms, R ⁴ is a linear or branched alkylene group having 1 to 4 carbon atoms, and R ⁵ is a linear or branched alkylene group having 1 to 4 carbon atoms. Alkyl group or the following formula

(R ³ is the same as above.)
It is a group represented by. m represents an integer of 1 to 3. ]
4. The composition according to 2 or 3, which further contains a curing catalyst and is a curable composition,
5. A coating agent comprising the composition according to any one of 2 to 4.
6. The cured film of the coating agent according to 5,
7. A coated article having a substrate and the cured film according to 6 formed directly or via one or more other layers on at least one surface of the substrate.
8. A silane compound having a hydrolyzable group is hydrolyzed and condensed in an environment containing no solvent having a relative permittivity of 7.0 or more and 9.0 or less, and an organopoly having a structure represented by the above average formula (I). The method for producing a composition according to any one of 2 to 4, which comprises a step of adding a solvent having a relative permittivity of 7.0 or more and 9.0 or less after synthesizing the siloxane.

The organopolysiloxane of the present invention is excellent in low-temperature quick-curing property, crack resistance, and solvent resistance, and the composition containing the organopolysiloxane gives a cured film having a high hardness. Suitable for manufacturing.

Hereinafter, the present invention will be specifically described.
[Organopolysiloxane]
The organopolysiloxane of the present invention has a structure represented by the following average formula (I).

In formula (I), R ¹ represents an alkyl group, an aralkyl group or an aryl group having 1 to 8 carbon atoms, which may be independently substituted with a hydrogen atom or a halogen atom, respectively, and R ² is Represents a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an i-propyl group or an acetyl group.

In R ¹ , the alkyl group having 1 to 8 carbon atoms may be linear, branched or cyclic, and specific examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl and i-butyl. , Tert-butyl, neopentyl, n-hexyl, cyclohexyl, n-heptyl, n-octyl group and the like, but an alkyl group having 1 to 3 carbon atoms is preferable, and a methyl group and an ethyl group are more preferable.
The number of carbon atoms of the aralkyl group is preferably 7 to 20, and specific examples thereof include a benzyl group and a phenylethyl group.
The number of carbon atoms of the aryl group is preferably 6 to 18, and specific examples thereof include unsubstituted aryl groups such as phenyl and naphthyl groups; trill, xsilyl, ethylphenyl, propylphenyl, butylphenyl, pentylphenyl, hexylphenyl and heptyl. Examples thereof include an alkylaryl group having 7 to 18 carbon atoms such as phenyl, octylphenyl, nonylphenyl, decylphenyl, undecylphenyl and dodecylphenyl group, but a phenyl group is preferable.
The alkyl group, aralkyl group, and aryl group may have a part or all of their hydrogen atoms substituted with halogen atoms (fluorine, chlorine, bromine, iodine atom), and specific examples thereof include chloro. Examples thereof include a methyl group, a chloropropyl group, a bromoethyl group, a trifluoropropyl group, a chlorophenyl group and a bromophenyl group.

Although a is a number satisfying 0 ≦ a <1, 0 ≦ a ≦ 0.3 is preferable from the viewpoint of the crack suppressing effect.
b is a number satisfying 0 <b ≦ 1, but 0.2 ≦ b ≦ 1 is preferable from the viewpoint of scratch resistance of the obtained cured product.
Although c is a number satisfying 0 ≦ c <1, 0 ≦ c ≦ 0.5 is preferable from the viewpoint of curability of the composition and hardness of the obtained cured product.
Although d is a number satisfying 0 ≦ d <1, 0 ≦ d ≦ 0.4 is preferable from the viewpoint of curability of the composition and hardness of the obtained cured product.
Although e is a number satisfying 0 <e≤4, e is effective in suppressing the condensation reaction by the condensing functional group and from the viewpoint of crack resistance, water resistance and weather resistance of the obtained cured product. Is preferably a number satisfying 0 <e ≦ 3.
It should be noted that a + b + c + d = 1.

The organopolysiloxane of the present invention may be a single composition or a mixture of a plurality of compounds having different compositions. Specifically, it can be suitably produced by mixing a plurality of compounds having different average compositions.

In the present invention, it is preferable to use two or more kinds of organopolysiloxanes having different weight average molecular weights in combination. For example, an organopolysiloxane having a weight average molecule of preferably less than 3,000, more preferably 1,000 or more and less than 3,000, and a weight average molecular weight of preferably 3,000 or more, more preferably 3,000 or more 20, It can be combined with up to 000 organopolysiloxanes. As these organopolysiloxanes, those having a weight average molecular weight of less than 3,000 and those having a weight average molecular weight of 3,000 or more are preferably 10/90 to 90/10, more preferably 20/80 to 80/20 in terms of mass ratio. Can be combined at the ratio of.

Further, the organopolysiloxane of the present invention preferably has a non-volatile content of 90% by mass or more excluding a solvent or the like. If the amount of volatile matter is large, it may cause deterioration of appearance and deterioration of mechanical properties due to void generation when the composition is cured.

The organopolysiloxane of the present invention has Mw1 in a region where Mw is 3,000 or more and Mw is more than 1,000 and less than 3,000 in the polystyrene-equivalent weight average molecular weight (Mw) distribution in gel permeation chromatography (GPC). When the region of Mw2 and the region of Mw of 1,000 or less are Mw3, each of Mw1 and Mw3 has one or more peak tops. Further, when the peak area SMw1 in the entire Mw1 region is 1, the value of the peak area SMw3 in the total amount region of Mw3 is 0.5 to 2.0.

The weight average molecular weight of the organopolysiloxane of the present invention is preferably 1,000 to 500,000, more preferably 1,500 to 300,000 in terms of polystyrene-equivalent weight average molecular weight by GPC. If the weight average molecular weight is less than 1,000, condensation may not proceed sufficiently, the storage stability of the organopolysiloxane may be lowered, and a condensation reaction may occur over time, resulting in poor crack resistance. If the molecular weight is more than 500,000, the organopolysiloxane becomes insoluble in the solvent, which may cause unevenness and uneven coating.
As the measurement condition of GPC, for example, the method used in a later embodiment can be adopted.

The organopolysiloxane of the present invention can be produced according to a general method for producing an organopolysiloxane. For example, it can be obtained by hydrolyzing and condensing a silane compound having a hydrolyzable group.

The raw material for producing the organopolysiloxane is particularly limited as long as it is a silane compound containing 1 to 4 hydrolyzable groups of chlor or alkoxy group on the silicon atom and having an organic substituent satisfying the above conditions. It is not something that is done.
Specific examples thereof include tetrachlorosilane, tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, methyltrichlorosilane, methyltrimethoxysilane, methyltriethoxysilane, methyltriisopropoxysilane, and methyltributoxy. Silane, dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldiisopropoxysilane, trimethylchlorosilane, trimethylmethoxysilane, trimethylethoxysilane, trimethylisopropoxysilane, ethyltricrolsilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltricrol Silane, propyltrimethoxysilane, propyltriethoxysilane, butyltrichlorosilane, butyltrimethoxysilane, butyltriethoxysilane, hexyltrichlorosilane, hexyltrimethoxysilane, hexyltriethoxysilane, phenyltrichlorosilane, phenyltrimethoxysilane, phenyl Triethoxysilane, cyclohexyltrichlorosilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, propylmethyldichlorosilane, propylmethyldimethoxysilane, propylmethyldiethoxysilane, hexylmethyldichlorosilane, hexylmethyldimethoxysilane, hexylmethyldiethoxy Silane, phenylmethyldichlorosilane, phenylmethyldimethoxysilane, phenylmethyldiethoxysilane, diphenyldichlorosilane, diphenyldimethoxysilane, diphenyldiethoxysilane, dimethylphenylchlorsilane, dimethylphenylmethoxysilane, dimethylphenylethoxysilane, and these. However, methoxysilane and ethoxysilane are preferable because of their operability, ease of distilling off by-products, and easy availability of raw materials.
The silane compound may be used alone or in combination of two or more.

A hydrolysis catalyst may be used in carrying out the hydrolysis. As the hydrolysis catalyst, a conventionally known catalyst can be used, and it is preferable that the aqueous solution exhibits acidity of pH 2 to 7, and particularly acidic hydrogen halide, sulfonic acid, carboxylic acid, acidic or weakly acidic inorganic substance. Solid acids such as salts and ion exchange resins are preferred. Specific examples of acidic catalysts include hydrogen fluoride, hydrochloric acid, nitrate, sulfuric acid, methanesulfonic acid, p-toluenesulfonic acid, formic acid, acetic acid, maleic acid, benzoic acid, lactic acid, phosphoric acid, and sulfonic acid or carboxylic acid groups on the surface. Examples thereof include a cation exchange resin having.

The amount of the hydrolyzable catalyst used is not particularly limited, but in consideration of the rapid progress of the reaction and the ease of removal of the catalyst after the reaction, 0.0002 to 0.0002 to 1 mol of the hydrolyzable silane. The range of 0.5 mol is preferable.

The amount ratio of the hydrolyzable silane to the water required for the hydrolyzing condensation reaction is not particularly limited, but it is possible to prevent the catalyst from being deactivated to allow the reaction to proceed sufficiently and to remove water after the reaction. Considering the ease, a ratio of 0.1 to 10 mol of water is preferable with respect to 1 mol of hydrolyzable silane.

The reaction temperature at the time of hydrolysis condensation is not particularly limited, but is -10 to 150 ° C. in consideration of improving the reaction rate and preventing the decomposition of the organic functional group of the hydrolyzable silane. preferable.

A solvent may be used for hydrolysis condensation, but a solvent having a relative permittivity of 7.0 or more and 9.0 or less, which will be described later, is not used. Specific examples of the organic solvent that can be used include methanol, ethanol, propanol, acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, toluene, xylene and the like. When these organic solvents are used, it is preferable to remove them by a treatment such as a stripping step and replace them with a solvent having a relative permittivity of 7.0 or more and 9.0 or less.

[Composition]
The composition of the present invention contains the above-mentioned organopolysiloxane. The content of the organopolysiloxane (the pure content of the organopolysiloxane containing no solvent, the total amount when different types are contained) is preferably 10 to 95% by mass, more preferably 10 to 85% by mass, 20 by mass in the composition. -80% by mass is even more preferable, and 60 to 80% by mass is even more preferable. If this content (as a non-volatile content) is less than 10% by mass, a cured product having a sufficient thickness may not be obtained after coating, and if it exceeds 95% by mass, a smooth cured product may not be provided.

[solvent]
The composition of the present invention may contain a solvent, if necessary. Examples of the solvent include alcohols such as isopropanol and butanol, ethers such as tetrahydrofuran and diethylene glycol dimethyl ether, ketones such as methyl ethyl ketone and methyl isobutyl ketone, esters such as ethyl acetate and ethyl lactate, and propylene glycol monomethyl ether acetate. Examples thereof include esterified products of glycol ether.

The composition of the present invention preferably contains a solvent having a relative permittivity of 7.0 or more and 9.0 or less. Specifically, as the solvent having such a relative permittivity, for example, it is preferable that an alkylene glycol alkyl ether ester represented by the following general formula (II) or an alkylene glycol ester solvent is contained. These can be used alone or in combination of two or more. The relative permittivity in the present invention is a value measured at a measurement temperature of 20 ° C. in accordance with JIS C 2138: 2007.

In formula (II), R ³ is an alkyl group having 1 to 4 carbon atoms, R ⁴ is a linear or branched alkylene group ^{having 1 to 4 carbon atoms, and R 5} is an alkyl group having 1 to 4 carbon atoms. Group or the following formula

で表される基である。

It is a group represented by.

Specific examples of the alkyl groups having 1 to 4 carbon atoms of R ³ and R ⁵ include methyl, ethyl, n-propyl, n-butyl groups and the like. ^{Specific examples of the alkylene group having 1 to 4} carbon atoms of R 4 include methylene, ethylene, trimethylene, propylene, butylene group and the like. If they have multiple -COR ³ groups, they may be the same or different from each other. m represents an integer of 1 to 3.

Specific examples of the solvent represented by the above general formula (II) include ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, and diethylene glycol monobutyl ether. Acetate, Propylene Glycol Monomethyl Ether Acetate, Dipropylene Glycol Monomethyl Ether Acetate, Ethylene Glycol Monomethyl Ether Propionate, Ethylene Glycol Monoethyl Ether Propionate, Ethylene Glycol Monobutyl Ether Propionate, Diethylene Glycol Monomethyl Ether Propionate, Diethylene Glycol Monoethyl Ether propionate, diethylene glycol monobutyl ether propionate, propylene glycol monomethyl ether propionate, dipropylene glycol monomethyl ether propionate, ethylene glycol monomethyl ether butyrate, ethylene glycol monoethyl ether butyrate, ethylene glycol monobutyl ether butyrate , Diethylene glycol monomethyl ether butyrate, diethylene glycol monoethyl ether butyrate, diethylene glycol monobutyl ether butyrate, propylene glycol monomethyl ether butyrate, dipropylene glycol monomethyl ether butyrate, methoxybutyl acetate and other glycol monofatty acid esters; ethylene glycol diacetate , Diethylene glycol diacetate, propylene glycol diacetate, dipropylene glycol diacetate, ethylene glycol acetate propionate, ethylene glycol acetate butyrate, ethylene glycol propionate butyrate, ethylene glycol dipropionate, ethylene glycol dibutyrate, diethylene glycol acetate Propionate, Diethylene Glycol Acetate Butyrate, Diethylene Glycol Propionate Butyrate, Diethylene Glycol Dipropionate, Diethylene Glycol Dibutyrate, Propylene Glycol Acetate Propionate, Propylene Glycol Acetate Butyrate, Propylene Glycol Propionate Butyrate , Propylene glycol dipropionate, propylene glycol dibutylate, dipropylene glycol acetate propionate, dipropylene glycol acetate butyrate, dipropylene glycol propionate butyrate, dipropylene glycol dipropionate, dipropylene glycol dibutyrate, etc. Glycoldi fatty acid esters and the like can be mentioned.
Among these, ethylene glycol monobutyl ether acetate and propylene glycol monomethyl ether acetate are preferable in consideration of chemical stability, availability, and environmental impact.

When the solvent is blended, the content thereof is not particularly limited, but is preferably 5 to 200 parts by mass, more preferably 10 to 100 parts by mass with respect to 100 parts by mass of the organopolysiloxane.

In addition, any additive can be appropriately added to the composition of the present invention as long as the effect of the present invention is not impaired.
Specific examples of the additive include non-reactive silicone oil, reactive silicone oil, adhesion-imparting agent such as silane coupling agent, non-reactive polymer resin, filler, filler, leveling agent, rheology adjuster, and reactivity. Diluters, surfactants, dispersants, defoamers, anti-aging agents, antioxidants, antistatic agents, infrared absorbers, ultraviolet absorbers, light stabilizers, colorants, fluorescent agents, dye pigments, fragrances, polishing Examples include agents, rust preventives, thixotropy-imparting agents and the like. These can be used alone or in combination of two or more in appropriate amounts.

The viscosity of the composition of the present invention is not particularly limited, but the viscosity at 25 ° C. measured by a rotational viscometer is taken into consideration to improve molding or coating workability and suppress the occurrence of sujimura and the like. However, it is preferably 100,000 mPa · s or less, and more preferably 20,000 mPa · s or less. The lower limit is not particularly limited, but is preferably about 10 mPa · s.

[Curable composition]
The compositions of the present invention can form a coating by drying at room temperature and under heating conditions, but when using the composition, a curing catalyst, eg, to accelerate the curing rate or to obtain excellent coating properties. A condensation curing catalyst may be added, and a curable composition further containing a curing catalyst can be obtained.

The curing catalyst can be appropriately selected from known catalysts and used. For example, organic metal compounds such as organic tin compounds, organic titanium compounds, organic zirconium compounds and organic aluminum compounds; inorganic acids such as hydrochloric acid and sulfuric acid; p. -Organic acids such as toluenesulfonic acid, various aliphatic or aromatic carboxylic acids; ammonia; inorganic bases such as sodium hydroxide, tributylamine, 1,5-diazabicyclo [4.3.0] nonen-5 (DBN) , 1,8-Diazabicyclo [5.4.0] Undecene-7 (DBU) and other organic bases can be mentioned, and these may be used alone or in combination of two or more.

In the composition of the present invention, among these, an organic metal compound selected from an organic tin compound, an organic titanium compound and an organic aluminum compound is preferable, and specifically, dibutyltin dilaurate, dibutyltin dioctate, dibutyltin diacetate and dioctyl are preferable. Tin dilaurate, dioctyl tin dioctate, dioctyl tin diacetate, dibutyl tin bisacetyl acetate, dioctyl tin bisacetyl laurate, tetrabutyl titanate, tetranonyl titanate, tetraxethylene glycol methyl ether titanate, tetraxethylene glycol ethyl ether titanate, bis (acetyl) Acetnyl) dipropyl titanate, acetylacetone aluminum, aluminum bis (ethyl acetoacetate) mononormal butyrate, aluminum ethyl acetoacetate dinormal butyrate, aluminum tris (ethyl acetoacetate) and the like are suitable, and are particularly reactive and soluble. From the viewpoint of properties, tetrabutyl titanate, aluminum ethyl acetoacetate dinormal butyrate, aluminum bis (ethyl acetoacetate) mononormal butyrate and their hydrolyzates are preferable.
The content of the curing catalyst is preferably 0.01 to 30 parts by mass, more preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the organopolysiloxane.

[Production method]
The composition of the present invention can be obtained, for example, by mixing one kind alone or a mixture of two or more kinds of organopolysiloxanes obtained from a single compound or a plurality of compounds having different compositions, and an arbitrary component. As a mixture of organopolysiloxanes, specifically, for example, a plurality of organopolysiloxanes having completed the hydrolysis condensation reaction are mixed and neutralized in the same reaction vessel to obtain the desired organopolysiloxane. Obtainable.

The ratio of the solvent having a relative permittivity of 7.0 or more and 9.0 or less in the whole solvent constituting the composition is preferably 20 to 100% by mass, more preferably 50 to 100% by mass, and the relative permittivity is 7.0 or more. Only 9.0 or less solvents may be used. When other organic solvents are used, they may be removed by a treatment such as a stripping step and replaced with a solvent having a relative permittivity of 7.0 or more and 9.0 or less.

[Coating agent and coated article]
The composition of the present invention described above can be suitably used as a coating agent, and can be particularly preferably used as an outer wall coating material, but its application is not limited to the coating agent. When used as a coating agent, for example, a film is formed by applying the composition of the present invention directly or via one or more other layers to at least one surface of a substrate and curing it. This makes it possible to obtain a coated article having a cured film of a coating agent formed directly on at least one surface of the substrate or via one or more other layers.

The base material is not particularly limited, and examples thereof include glass, silicon wafers, metals, plastic molded bodies, ceramics, and composites thereof.
In addition, the surface of these base materials is treated with chemical conversion treatment, corona discharge treatment, plasma treatment, acid or alkaline solution, or decorative plywood whose surface layer is coated with a different type of paint from the base material body. Can also be used. Examples of the other layer include those obtained by polyester resin coating, polyurethane resin coating, aminoalkyd resin coating, lacquer coating, spray coating, and water-based wax coating.

The coating agent may be appropriately selected from known methods as a method for applying the coating agent to the substrate. For example, roll coating, bar coating, wire bar coating, spray coating, flow coating, spin coating, curtain coating, knife coating, and immersion. Various coating methods such as coating and brush coating can be used. The coating amount is not particularly limited, but usually, the thickness of the film after drying is preferably 0.1 to 1,000 μm, and preferably 1 to 100 μm.

Examples of the method for curing the composition include room temperature curing and heat curing. The heating temperature is not particularly limited, but is preferably 100 to 300 ° C, more preferably 150 to 250 ° C.

Hereinafter, the present invention will be described in more detail with reference to Preparation Examples, Examples and Comparative Examples, but the present invention is not limited to the following Examples.
In the following, the weight average molecular weight is a value measured under the following conditions using GPC. The values a to e in the average formula (I) were calculated from the results of ^{1 1} H-NMR and ^{29 Si-NMR measurements.}
[GPC conditions]
Equipment: HLC-8220 (manufactured by Tosoh Corporation)
Columns: TSKgel GMH _XL- L, TSKgel G4000H _XL , TSKgel G2000H _XL x 2
Developing solvent: tetrahydrofuran (THF)
Flow rate: 1 mL / min
Detector: RI
Column constant temperature bath temperature: 40 ° C
Standard substance: polystyrene

[1] Preparation of component of organopolysiloxane (A) [Preparation Example 1] <A-1>
Tetramethoxysilane (manufactured by Tokyo Kasei Kogyo Co., Ltd.): 30.4 g (0.2 mol), hexamethyldisiloxane (manufactured by Tokyo Kasei Kogyo Co., Ltd.): 32.4 g (0.2 mol), methyltrimethoxy Silane: KBM-13 (manufactured by Shin-Etsu Chemical Co., Ltd.) 313.7 g (2.1 mol), Dimethyldimethoxysilane: KBM-22 (manufactured by Shin-Etsu Chemical Co., Ltd.) 386.9 g (3.0 mol), Phenyltrimethoxysilane: KBM-103 (manufactured by Shin-Etsu Chemical Co., Ltd.) 778.7 g (3.6 mol), diphenyldimethoxysilane: KBM-202 (manufactured by Shin-Etsu Chemical Co., Ltd.) 20.8 g (0.1) Mol) and 4.8 g of methanesulfonic acid were blended in a reactor, and when it became uniform, 253.2 g of ion-exchanged water was added, and the mixture was stirred at 80 ° C. for 2 hours.
A liquid having a weight average molecular weight of 4,800 was obtained as a silicone component excluding the solvent. The values of a to e in the average formula (I) were a = 0.03, b = 0.62, c = 0.32, d = 0.03, and e = 0.11, respectively.

[Preparation Example 2] <A-2>
Hexamethyldisiloxane (manufactured by Tokyo Kasei Kogyo Co., Ltd.): 32.4 g (0.2 mol), methyltrimethoxysilane: KBM-13 (manufactured by Shin-Etsu Chemical Co., Ltd.) 672.8 g (4.5 mol) , Phenyltrimethoxysilane: KBM-103 (manufactured by Shin-Etsu Chemical Co., Ltd.) 507.8 g (2.4 mol) and 3.5 g of methanesulfonic acid were mixed in a reactor, and when it became uniform, ion-exchanged water was added. 222.3 g was added, and the mixture was stirred at 80 ° C. for 2 hours.
A viscous liquid was obtained at 25 ° C. with a weight average molecular weight of 7,500 as the silicone component excluding the solvent. The values of a to e in the average formula (I) were a = 0, b = 0.96, c = 0, d = 0.04, and e = 0.14, respectively.

[Preparation Example 3] <A-3>
Methyltrimethoxysilane: KBM-13 (manufactured by Shin-Etsu Chemical Co., Ltd.) 666.6 g (4.5 mol), phenyltrimethoxysilane: KBM-103 (manufactured by Shin-Etsu Chemical Co., Ltd.) 507.8 g (2. 4 mol), 3.5 g of methanesulfonic acid was blended in a reactor, and when it became uniform, 222.3 g of ion-exchanged water was added, and the mixture was stirred at 80 ° C. for 2 hours.
A liquid having a weight average molecular weight of 10,000 was obtained as a silicone component excluding the solvent. The values of a to e in the average formula (I) were a = 0, b = 1.0, c = 0, d = 0, and e = 0.23, respectively.

[Preparation Example 4] <A-4>
Methyltrimethoxysilane: KBM-13 (manufactured by Shin-Etsu Chemical Co., Ltd.) 313.7 g (2.1 mol), dimethyldimethoxysilane: KBM-22 (manufactured by Shin-Etsu Chemical Co., Ltd.) 382.9 g (3.0) Mol), phenyltrimethoxysilane: KBM-103 (manufactured by Shin-Etsu Chemical Co., Ltd.) 778.7 g (3.7 mol) and 4.8 g of methanesulfonic acid were blended in a reactor, and ions were formed when they became uniform. 253.2 g of exchanged water was added, and the mixture was stirred at 80 ° C. for 2 hours.
A liquid having a weight average molecular weight of 3,600 was obtained as a silicone component excluding the solvent. The values of a to e in the average formula (I) were a = 0, b = 0.66, c = 0.34, d = 0, and e = 0.12, respectively.

[2] Preparation of organopolysiloxane (B) component [Preparation Example 5] <B-1>
Tetramethoxysilane (manufactured by Tokyo Kasei Kogyo Co., Ltd.): 15.2 g (0.1 mol), methyltrimethoxysilane: KBM-13 (manufactured by Shin-Etsu Chemical Co., Ltd.) 525.5 g (3.5 mol), Phenyltrimethoxysilane: KBM-103 (manufactured by Shin-Etsu Chemical Co., Ltd.) 126.9 g (0.6 mol), diphenyldimethoxysilane: KBM-202 (manufactured by Shin-Etsu Chemical Co., Ltd.) 119.0 (0.5) Mol) was compounded in a reactor, and when it became uniform, 160.0 g of 0.5% silane was added, and the mixture was stirred at 80 ° C. for 2 hours.
A liquid having a weight average molecular weight of 2,900 was obtained as a silicone component excluding the solvent. The values of a to e in the average formula (I) were a = 0.02, b = 0.88, c = 0.10, d = 0, and e = 0.21, respectively.

[Preparation Example 6] <B-2>
Methyltrimethoxysilane: KBM-13 (manufactured by Shin-Etsu Chemical Co., Ltd.) 675.0 g (4.5 mol), diphenyldimethoxysilane: KBM-202 (manufactured by Shin-Etsu Chemical Co., Ltd.) 120.0 g (0.5) Mol) was added to the reactor, and when it became uniform, 160.0 g of 0.5% hydrochloric acid was added, and the mixture was stirred at 80 ° C. for 2 hours.
A liquid having a weight average molecular weight of 2,500 was obtained as a silicone component excluding the solvent. The values of a to e in the average formula (I) were a = 0, b = 0.90, c = 0.10, d = 0, and e = 0.24, respectively.

[Preparation Example 7] <B-3>
Methyltrimethoxysilane: KBM-13 (manufactured by Shin-Etsu Chemical Co., Ltd.) 224.3 g (1.5 mol) Phenyltrimethoxysilane: KBM-103 (manufactured by Shin-Etsu Chemical Co., Ltd.) 528.8 g (2.5) Mol) was added to the reactor, and when it became uniform, 160.0 g of 0.5% silane was added, and the mixture was stirred at 80 ° C. for 2 hours.
A liquid having a weight average molecular weight of 2,700 was obtained as a silicone component excluding the solvent. The values of a to e in the average formula (I) were a = 0, b = 1.0, c = 0, d = 0, and e = 0.20, respectively.

[3] Production of Composition Containing Organopolysiloxane [Example 1-1]
50.0 g of the B-1 solution was mixed with 50.0 g of the A-1 solution, 0.1 g of synthetic hydrotalcite was added, and the mixture was stirred for 2 hours to neutralize. 70.0 g of propylene glycol monomethyl ether acetate (manufactured by Dow Chemical Co., Ltd., relative permittivity 8.3 (20 ° C.)) was added, volatile components such as methanol were distilled off under reduced pressure, and pressure filtration was performed to compose the composition. Manufactured a thing.

[Examples 1-2 to 1-36]
The compositions of Examples 1-2 to 1-36 were produced by the same formulations as in Example 2-1 except that the compositions and blending ratios shown in Table 1 were changed.

[Comparative Example 1-1]
To 100 g of the A-1 solution, 0.1 g of synthetic hydrotalcite was added and stirred for 2 hours to neutralize. 70.0 g of propylene glycol monomethyl ether acetate (manufactured by Dow Chemical Co., Ltd., relative permittivity 8.3 (20 ° C.)) was added, volatile components such as methanol were distilled off under reduced pressure, and pressure filtration was performed.

[Comparative Examples 1-2-1-7]
The compositions of Comparative Examples 1-2 to 1-7 were produced by the same formulations as in Comparative Example 1-1 except that the compositions and blending ratios shown in Table 1 were changed.

The results of gel permeation chromatography of the compositions obtained in Examples 1-1 to 1-36 and Comparative Examples 1-1 to 1-7 are shown in Table 2. In the weight average molecular weight (Mw) distribution, the region where Mw is 3,000 or more is Mw1, the peak area of the Mw1 total amount region is SMw1, the region where Mw is more than 1,000 and less than 3,000 is the peak of Mw2, Mw2 total amount region. The area is SMw2, the region where Mw is 1,000 or less is Mw3, the peak area of the total amount region of Mw3 is SMw3, and the GPC area ratio shows the values of SMw2 and SMw3 when SMw1 is 1.

As shown in Table 2, in Examples 1-1 to 1-36, the value of SMw3 exists in the region of 0.5 to 2.0, but in Comparative Examples 1-1 to 1-4, the value of SMw3 exists in the region of 0.5 to 2.0. The value of SMw3 is less than 0.5, and in Comparative Examples 1-5 to 1-7, the value of SMw3 exceeds 2.0.

[4] Production of Covered Articles [Examples 2-1 to 2-36, Comparative Examples 2-1 to 2-7]
Aluminum alkoxide compounds (aluminum ethyl acetoacetate dinormal butyrate and aluminum bis Add 2 parts by mass of DX-9740 (manufactured by Shin-Etsu Chemical Industry Co., Ltd.) (a mixture of ethylacetacetate) mononormal butyrate, apply it on a metal substrate by flow coating, and heat it in a dryer at 180 ° C. for 30 minutes. It was baked. The content of the component (B) in the composition of Examples 2-1 to 2-36 is 15% by mass or more.
The appearance of the coating film, the rubbing test, and the pencil hardness of the obtained coated article were evaluated. The results are shown in Table 3.

(1) Appearance of the coating film Visually, the coating film having a uniform surface and no irregularities or cracks due to agglomerates was regarded as OK, and those having cracks or agglomerates due to irregularities were regarded as NG.
(2) Rubbing test Acetone was immersed in Bencot M-3II (manufactured by Asahi Kasei Corporation, area 4 cm ² ), and the surface was rubbed 30 times with a load of 500 g to evaluate the appearance of the coating film visually. Those in which no change was observed in the appearance of the coating film after the rubbing test as compared with the appearance of the coating film before the test were regarded as OK, and those in which peeling or whitening of the coating film was observed were regarded as NG.
(3) Pencil hardness Measured under a load of 750 g according to JIS K5600-5-4. If a scratch was found with a 6B pencil, it was set to <6B.

As shown in Table 3, in Examples 2-1 to 2-36, a coating film having a hardness of B or higher with no cracks was obtained under curing conditions of 180 ° C. for 30 minutes. In Examples 2-1 to 2-7, the coating film had a pencil hardness of 2B or less and an insufficient hardness. In addition, cracks and cracks were also observed in the coating film of Comparative Examples 2-5 to 2-7.

Claims (8)

The following average formula (I)

(In the formula, R ¹ represents an alkyl group, an aralkyl group or an aryl group having 1 to 8 carbon atoms, which may be independently substituted with a hydrogen atom or a halogen atom, respectively, and R ² is a hydrogen atom. , Methyl group, ethyl group, n-propyl group, i-propyl group or acetyl group. A, b, c and d are 0 ≦ a <1, 0 <b ≦ 1, 0 ≦ c <1, respectively. It is a number that satisfies 0 ≦ d <1, a + b + c + d = 1, and e is a number that satisfies 0 <e ≦ 4.)
Has a structure represented by
In the polystyrene-equivalent weight average molecular weight (Mw) distribution in gel permeation chromatography, when the region with Mw of 3,000 or more is Mw1 and the region with Mw of 1,000 or less is Mw3, one or more in Mw1 and Mw3, respectively. Organopolysiloxane having a peak top of Mw1 and having a peak area SMw1 of the entire Mw1 region as 1, and a value of the peak area SMw3 of the total amount region of Mw3 being 0.5 to 2.0. A composition containing 10% by mass or more of the organopolysiloxane according to claim 1 and a solvent having a relative permittivity of 7.0 or more and 9.0 or less. The composition according to claim 2, wherein the solvent having a relative permittivity of 7.0 or more and 9.0 or less contains a compound represented by the following general formula (II).

[In the formula, R ³ is an alkyl group having 1 to 4 carbon atoms, R ⁴ is a linear or branched alkylene group having 1 to 4 carbon atoms, and R ⁵ is a linear or branched alkylene group having 1 to 4 carbon atoms. Alkyl group or the following formula

(R ³ is the same as above.)
It is a group represented by. m represents an integer of 1 to 3. ] The composition according to claim 2 or 3, further comprising a curing catalyst and being a curable composition. A coating agent comprising the composition according to any one of claims 2 to 4. The cured film of the coating agent according to claim 5. A coated article having a base material and a cured film according to claim 6, which is formed on at least one surface of the base material directly or through one or more other layers. A silane compound having a hydrolyzable group is hydrolyzed and condensed in an environment containing no solvent having a relative permittivity of 7.0 or more and 9.0 or less, and an organopoly having a structure represented by the above average formula (I). The method for producing a composition according to any one of claims 2 to 4, which comprises a step of adding a solvent having a relative permittivity of 7.0 or more and 9.0 or less after synthesizing the siloxane.