JP2021113256A - Emulsion, and production method thereof - Google Patents

Abstract

To provide an emulsion with less viscosity change that has enlargement of an emulsion particle size suppressed and degradation of water absorption whitening ability prevented in passage of time.SOLUTION: An emulsion contains a silicone component obtained by hydrolysis condensation of a component (A), an organic silane compound represented by following formula (1). ( R1 is a phenyl group or a cyclohexyl group, R2 is a hydrogen atom or a hydrocarbon group, and R3 is an alkoxy group of 1-3 carbons, an acetoxy group, or a hydroxy group). The amount of a silanol group-containing segment in the silicone component obtained by hydrolysis condensation of the component (A) is less than 1 mol% to the total amount of a segment derived from a silicone structure of the component (A).SELECTED DRAWING: None

Description

The present invention relates to emulsions and methods for producing them.

Conventionally, an aqueous emulsion obtained by emulsion polymerization has been widely used as a resin for an aqueous paint because a film obtained by drying and forming the aqueous emulsion at room temperature or under heating exhibits relatively good durability. ..
In recent years, there has been a demand for a coating material having weather resistance for a longer period of time, and an organic-inorganic polymer in which an organic polymer typified by an acrylic polymer and a silane compound are combined has been proposed. In addition, a house that has achieved ultra-high durability for 30 to 100 years has also been proposed, and an organic-inorganic composite polymer having a high ratio of silane compounds is used as a paint for its outer wall coating.
Under such circumstances, Patent Document 1 discloses an emulsion in which polysiloxane is compounded.

Further, Patent Documents 2 and 3 disclose an emulsion in which polysiloxane is compounded and which uses polysiloxane obtained from a specific organic silane compound. Further, Patent Documents 4 to 7 propose highly durable emulsions using silane compounds having a phenyl group or a cycloalkyl group.

Patent Document 8 discloses a method for producing an emulsion containing a polysiloxane, in which the pH is set to 1.5 or more and 2.4 or less in the polymerization step when preparing the emulsion, and the polymerization step is performed. After that, it has a step of removing the by-product alcohol and a step of heat-treating at pH 10 or higher.

Japanese Unexamined Patent Publication No. 05-093071 Japanese Unexamined Patent Publication No. 08-003409 Japanese Unexamined Patent Publication No. 2000-319579 Japanese Unexamined Patent Publication No. 2006-273919 Japanese Unexamined Patent Publication No. 2008-38113 Japanese Unexamined Patent Publication No. 2009-7513 JP-A-2010-59379 Patent No. 654207

When the water-based emulsion paint is used for painting the outer wall, the paint is blended from the viewpoint of preventing sagging on the wall surface and obtaining viscosity characteristics suitable for the coating state of the uneven portion to be painted. If the viscosity of the paint changes during the painting process, there is a risk of sagging on the wall surface and poor coating of uneven parts. Therefore, an emulsion that can maintain the viscosity characteristics during compounding and has excellent stability over time is required. .. However, conventionally, many emulsions obtained by using an organic silane compound are inferior in stability with time, and in particular, there is a problem that the emulsion particles are enlarged with time and cause a change in viscosity. A coating film obtained from a paint containing bloated emulsion particles has a problem that a fine-packed structure cannot be formed at the time of film formation, which causes a decrease in performance such as water absorption and whitening performance.

All of the conventional coating films disclosed in Patent Documents 1 to 7 are said to have improved weather resistance. However, the emulsions of Patent Documents 1 to 7 have room for improvement in stability over time, particularly in viscosity change and deterioration of coating film performance caused by change in particle size in the emulsion in which polysiloxane is compounded.

The emulsion of Patent Document 8 is said to be able to prevent a change in viscosity and a decrease in coating film performance caused by a change in particle size, particularly stability over time in an emulsion in which polysiloxane is compounded, and these performances are further improved. Is required to do.

Therefore, in the present invention, an emulsion in which the enlargement of the particle size of the emulsion particles over time is suppressed, the viscosity change with time is small, the stability with time is excellent, and the deterioration of the water absorption bleaching performance is prevented even after aging. The purpose is to provide.

As a result of intensive studies to solve the above-mentioned problems of the prior art, the present inventors have found that an emulsion containing a silicone component after hydrolysis and condensation of a predetermined organic silane compound in a specific silanol group-containing segment amount has been obtained. We found that it is an emulsion in which the enlargement of the particle size of the emulsion particles with time is suppressed, the viscosity change with time is small, the stability with time is excellent, and the deterioration of the water absorption bleaching performance is prevented even after aging. The invention was completed.

（式（１）中、
Ｒ¹は、フェニル基又はシクロヘキシル基であり、
Ｒ²は、水素原子又は炭素数１〜８の脂肪族炭化水素基であり、
Ｒ³は、それぞれ独立して、炭素数１〜３のアルコキシ基、アセトキシ基、又は水酸基であり、
（ｎ，ｍ）は、（０，１）、（０，２）、（１，０）及び（２，０）からなる組み合わせの群より選ばれる少なくとも一種である。）；

（式（２）中、
Ｄは、式（１）において、Ｒ³が４−（ｎ＋ｍ）が２の場合での²⁹Ｓｉ固体ＮＭＲスペクトルで同定されるシグナル量であり、Σは、その積分値であり、
Ｔは、式（１）において、Ｒ³が４−（ｎ＋ｍ）が３の場合での²⁹Ｓｉ固体ＮＭＲスペクトルで同定されるシグナル量であり、Σは、その積分値であり、
Ｄ及びＴの添え字の数字は、それぞれのＳｉ−Ｏ結合手数を表す。）
［２］
（Ａ）成分、（Ｂ）成分、及び（Ｃ）成分を単量体成分として含む共重合体と、水と、を含む、
［１］に記載のエマルジョン。
（Ａ）成分：式（１）で表される有機シラン化合物
（Ｂ）成分：下記（ｂ１）、（ｂ２）のエチレン性不飽和単量体（ただし、エチレン性不飽和基を有する有機シラン化合物を除く。）、
（ｂ１）不飽和カルボン酸エステル単量体、
（ｂ２）不飽和カルボン酸単量体、
（Ｃ）成分：エチレン性不飽和基を有する有機シラン化合物
［３］
（Ａ）成分、（Ｂ）成分、及び（Ｃ）成分の合計に対する（Ａ）成分の含有比率が、３０質量％以下である、
［２］に記載のエマルジョン。
［４］
（Ｃ）成分が、γ−アクリロキシプロピルトリメトキシシラン、γ−アクリロキシプロピルトリエトキシシラン、γ−メタクリロキシプロピルトリメトキシシラン、γ−メタクリロキシプロピルトリエトキシシラン、γ−メタクリロキシプロピルメチルジメトキシシランからなる群より選ばれる１種以上である、
［１］〜［３］のいずれかに記載のエマルジョン。
［５］
（Ｅ）成分：触媒をさらに含む、
［１］〜［４］のいずれかに記載のエマルジョン。
［６］
［１］〜［５］のいずれかに記載のエマルジョンの製造方法であって、
（Ａ）成分の加水分解縮合反応と、（Ｂ）成分の付加重合反応と、（Ｃ）成分の加水分解縮合反応及び付加重合反応とを、（Ｅ）成分の存在下で行う工程を含む、製造方法。
（Ａ）成分：式（１）で表される有機シラン化合物
（Ｂ）成分：下記（ｂ１）、（ｂ２）のエチレン性不飽和単量体（ただし、エチレン性不飽和基を有する有機シラン化合物を除く。）、
（ｂ１）不飽和カルボン酸エステル単量体、
（ｂ２）不飽和カルボン酸単量体、
（Ｃ）成分：エチレン性不飽和基を有する有機シラン化合物
（Ｅ）成分：触媒 That is, the present invention is as follows.
[1]
An emulsion containing a silicone component after hydrolysis and condensation of the component (A).
The amount of silanol group-containing segments in the silicone component after hydrolysis and condensation of the component (A) defined by the following formula (2) is less than 1 mol% with respect to the total amount of segments derived from the silicone structure of the component (A). There is an emulsion.
Component (A): Organic silane compound represented by the following formula (1)

(In equation (1),
R ¹ is a phenyl group or a cyclohexyl group and
R ² is a hydrogen atom or an aliphatic hydrocarbon group having 1 to 8 carbon atoms.
R ³ is independently an alkoxy group, an acetoxy group, or a hydroxyl group having 1 to 3 carbon atoms.
(N, m) is at least one selected from the group of combinations consisting of (0,1), (0,2), (1,0) and (2,0). );

(In equation (2),
In equation (1), D is the ^{amount of signal identified in the 29 Si solid-state NMR spectrum when R 3} is 4- (n + m) is 2, and Σ is the integral value thereof.
^{T is the amount of signal identified in the 29 Si solid-state NMR spectrum when R 3} is 4- (n + m) in equation (1), and Σ is the integral value thereof.
The numbers in the subscripts of D and T represent the respective Si—O coupling steps. )
[2]
A copolymer containing the component (A), the component (B), and the component (C) as a monomer component, and water.
The emulsion according to [1].
Component (A): Organic silane compound represented by the formula (1) Component (B): Ethylene unsaturated monomer of the following (b1) and (b2) (however, an organic silane compound having an ethylenically unsaturated group) except for.),
(B1) Unsaturated carboxylic acid ester monomer,
(B2) Unsaturated carboxylic acid monomer,
Component (C): Organic silane compound having an ethylenically unsaturated group [3]
The content ratio of the component (A) to the total of the component (A), the component (B), and the component (C) is 30% by mass or less.
The emulsion according to [2].
[4]
The component (C) is γ-acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-methacryloxypropylmethyldimethoxysilane. One or more species selected from the group consisting of
The emulsion according to any one of [1] to [3].
[5]
Component (E): Further containing a catalyst,
The emulsion according to any one of [1] to [4].
[6]
The method for producing an emulsion according to any one of [1] to [5].
A step of performing a hydrolysis condensation reaction of a component (A), an addition polymerization reaction of a component (B), and a hydrolysis condensation reaction and an addition polymerization reaction of a component (C) in the presence of the component (E) is included. Production method.
Component (A): Organic silane compound represented by the formula (1) Component (B): Ethylene unsaturated monomer of the following (b1) and (b2) (however, an organic silane compound having an ethylenically unsaturated group) except for.),
(B1) Unsaturated carboxylic acid ester monomer,
(B2) Unsaturated carboxylic acid monomer,
Component (C): Organic silane compound having an ethylenically unsaturated group (E) Component: Catalyst

According to the present invention, an emulsion in which the enlargement of the particle size of the emulsion particles over time is suppressed, the viscosity change with time is small, the stability with time is excellent, and the deterioration of the water absorption bleaching performance is prevented even after aging. Obtainable.

^{The 29} Si solid-state NMR spectrum of the emulsion of Comparative Example 3 is shown.

Hereinafter, a mode for carrying out the present invention (hereinafter, referred to as “the present embodiment”) will be described in detail, but the present invention is not limited to the following description, and is appropriately within the scope of the gist thereof. It can be transformed and implemented.

[Emulsion]
The emulsion of the present embodiment contains a silicone component after hydrolysis and condensation of an organic silane compound represented by the following formula (1) (hereinafter, also referred to as component (A)).

In equation (1),
R ¹ is a phenyl group or a cyclohexyl group and
R ² is a hydrogen atom or an aliphatic hydrocarbon group having 1 to 8 carbon atoms.
R ³ is independently an alkoxy group, an acetoxy group, or a hydroxyl group having 1 to 3 carbon atoms.
(N, m) is at least one selected from the group of combinations consisting of (0,1), (0,2), (1,0) and (2,0).

In the emulsion of the present embodiment, the silanol group-containing segment amount in the silicone component after hydrolysis and condensation of the component (A) defined by the following formula (2) is the total amount of segments derived from the silicone structure of the component (A). On the other hand, it is less than 1 mol%.

In equation (2),
In equation (1), D is the ^{amount of signal identified in the 29 Si solid-state NMR spectrum when R 3} is 4- (n + m) is 2, and Σ is the integral value thereof.
^{T is the amount of signal identified in the 29 Si solid-state NMR spectrum when R 3} is 4- (n + m) in equation (1), and Σ is the integral value thereof.
The numbers in the subscripts of D and T represent the respective Si—O coupling steps.

The present inventors have found that the uncondensed silanol groups after the hydrolysis-condensation reaction of an organic silane compound affect the stability over time in an emulsion in which a polysiloxane is compounded. More specifically, the present inventors have found that there is a correlation between the uncondensed silanol groups and the change in particle size after the hydrolysis condensation reaction of the organic silane compound.
^{For example, the amount of silanol group-containing segments after hydrolysis condensation identified and quantified by the 29} Si solid-state NMR spectrum can be controlled to a predetermined value or less by the emulsion production method described later, and the emulsion particles over time can be controlled. An emulsion can be obtained in which the enlargement of the particle size is suppressed, the viscosity change with time is small, the stability with time is excellent, and the deterioration of the water absorption bleaching performance is prevented even after the time has passed.

The amount of silanol group-containing segments is 1 mol% with respect to the total amount of segments derived from the silicone structure of the component (A) from the viewpoint of improving the stability of the particle size over time and the stability of the emulsion over time and preventing the deterioration of the water absorption bleaching performance. It may be less than 0.9 mol% or less, and may be 0.8 mol% or less.
The lower limit of the silanol group-containing segment amount is not particularly limited, but is usually 0 mol% or more, may exceed 0 mol%, may be 0.1 mol% or more, and may be 0.2 mol% or more. May be.
Examples of the method for controlling the amount of silanol group-containing segments to less than 1 mol% include adjusting the amount of component (A) used in the production of an emulsion, appropriately selecting the type of catalyst to be used, and the like. Be done.

As a method for evaluating the amount of silanol group-containing segments, ²⁹ Si solid-state NMR measurement method (DD / MAS method) can be applied.
In the ²⁹ Si solid-state NMR measurement method (DD / MAS method), according to the ²⁹ Si solid-state NMR spectrum, in the formula (1), when R ³ is 4- (n + m) = 2, and R ³ is 4- (n + m). The signal of each segment having a different number of uncondensed silanol groups can be detected by the difference in the number of Si—O bonds in the case of) = 3.
Then, the amount of uncondensed silanol group-containing segment (mol%) can be calculated by using the signal integral value of each of the other segments.

In the emulsion of the present embodiment, in addition to the silicone component after hydrolysis and condensation of the component (A),
The organic silane compound represented by the formula (1) (that is, the component (A)), the unsaturated carboxylic acid ester monomer (hereinafter, also referred to as the component (b1)), the unsaturated carboxylic acid monomer (hereinafter, (hereinafter,). The ethylenically unsaturated monomer (hereinafter, also referred to as (B) component) of b2) component) and the organic silane compound having an ethylenically unsaturated group (hereinafter, also referred to as (C) component) are simply referred to. It is preferable to contain a copolymer contained as a metric component and water.
Here, the component (B) is not an organic silane compound having an ethylenically unsaturated group.
The component (A), the component (B), and the component (C) may exist as particles of a polymerized copolymer in the emulsion, and may be adsorbed on the emulsion particles as an unreacted product or in the aqueous emulsion phase. It may exist.
Further, the type of polymerization of the copolymer containing the component (A), the component (B), and the component (C) as a monomer component is not particularly limited. The copolymer may include, for example, a polymerization unit of the component (A) and a polymerization unit of the component (B) grafted via the component (C). Further, in the above emulsion, the polymer of the component (A), the polymer of the component (A) and the component (C), the polymer of the component (B), and the polymer of the component (B) and the component (C) are included. It may contain a product of a copolymerization reaction such as a polymer.

The content ratio of the component (A) in the copolymer is preferably 30% by mass or less, more preferably 25% by mass, based on the total of the components (A), (B), and (C). It is less than or equal to, more preferably 21% by mass or less.
The lower limit of the content ratio of the component (A) is not particularly limited, but is usually in excess of 0% by mass, preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and further preferably. Is 1.0% by mass or more.
When the content ratio of the component (A) is 30% by mass or less, the amount of the silanol group-containing segment tends to be controlled to less than 1 mol%, and as a result, the particle size of the emulsion particles increases with time. There is a tendency to obtain a coating film that suppresses the emulsion, has excellent stability over time, can prevent deterioration of water absorption and whitening performance, and has excellent long-term weather resistance.
Further, when the content ratio of the component (A) is 0.1% by mass or more, the presence of the siloxane bond introduced into the emulsion tends to obtain a coating film having better long-term weather resistance.

Hereinafter, the components (A) and (B) and the components (C), which are monomers constituting the copolymer contained in the emulsion of the present embodiment, will be described.

(Component (A): Organic silane compound)
Preferred specific examples of the (A) organic silane compound are shown below.
In the combination in which (n, m) is (0,1) in the formula (1), for example, methyltrimethoxysilane, methyltriethoxysilane and the like can be mentioned. By using these, there is a tendency that the crosslink density of polysiloxane can be imparted and the hardness of the coating film can be improved.

In the combination of formula (1) where (n, m) is (0,2), for example, dimethyldimethoxysilane, dimethyldiethoxysilane and the like can be mentioned. By using these, there is a tendency that the crosslink density of the polysiloxane can be lowered and the coating film can be imparted with flexibility.

In the combination of formula (1) where (n, m) is (1,0), for example, phenyltrimethoxysilane, phenyltriethoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane and the like can be mentioned. By using these, there is a tendency that the crosslink density of the polysiloxane can be imparted and the compatibility with the component (B) can be imparted.

Examples of the combination in which (n, m) is (2,0) in the formula (1) include diphenyldimethoxysilane, diphenyldiethoxysilane, dicyclohexyldimethoxysilane, and dicyclohexyldiethoxysilane. By using these, the crosslink density of the polysiloxane can be lowered, flexibility can be imparted to the coating film, and compatibility with the component (B) can be imparted.

Therefore, it is possible to design the desired coating film physical properties by appropriately combining two or more kinds of the above-mentioned (n, m) combination of organic silane compounds.

Examples of the organic silane compound other than the combination of (n, m) described above include combinations of (0,3) and (0,0) where (n, m) is (0,0). In the combination of (0,3), trimethylmonomethoxysilane and the like can be mentioned, and in the combination of (0,0), tetraethoxysilane and the like can be mentioned. These organic silane compounds can be used as necessary in combination with the organic silane compound of the combination of (0,1), (0,2), (1,0), and (2,0). ..

(Component (B): Ethylene unsaturated monomer)
The copolymer contained in the emulsion of the present embodiment contains (B1) unsaturated carboxylic acid ester monomer and (b2) unsaturated carboxylic acid monomer as the component (B): ethylenically unsaturated monomer. Is preferably included. As the component (b1) and the component (b2), only one type may be used alone, or two or more types may be used in combination.

<Component (b1): unsaturated carboxylic acid ester monomer>
As the component (b1) component: unsaturated carboxylic acid ester monomer in the present embodiment, for example, (meth) acrylic acid ester (in the present specification, acrylic acid and methacrylic acid are collectively referred to as (meth) acrylic acid. ).
The unsaturated carboxylic acid ester (b1) is not limited to the following, but for example, the (meth) acrylic acid alkyl ester having 1 to 18 carbon atoms in the alkyl portion and the number of ethylene oxide groups from 1 to 100. (Poly) oxyethylene mono (meth) acrylate, (poly) oxypropylene mono (meth) acrylate, (meth) acrylic acid hydroxyalkyl ester having 1 to 18 carbon atoms in the alkyl part, and 1 ethylene oxide group. Examples thereof include up to 100 (poly) oxyethylene di (meth) acrylates.

The (meth) acrylic acid alkyl ester is not limited to the following, and includes, for example, methyl (meth) acrylic acid, ethyl (meth) acrylic acid, n-butyl (meth) acrylic acid, and (meth) acrylic acid. Examples thereof include isobutyl, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, dodecyl (meth) acrylate, and cycloalkyl ester of (meth) acrylate.

The (poly) oxyethylene mono (meth) acrylate is not limited to the following, and includes, for example, (meth) ethylene glycol (meth) acrylate, methoxy (meth) ethylene glycol acrylate, (meth) diethylene glycol (meth) acrylate, and methoxy. Examples thereof include diethylene glycol (meth) acrylate, tetraethylene glycol (meth) acrylate, and tetraethylene glycol methoxy (meth) acrylate.

The (poly) oxypropylene mono (meth) acrylate is not limited to the following, and is, for example, propylene glycol (meth) acrylate, propylene glycol methoxy (meth) acrylate, and dipropylene glycol (meth) acrylate. , Dipropylene glycol methoxy (meth) acrylate, tetrapropylene glycol (meth) acrylate, tetrapropylene glycol methoxy (meth) acrylate and the like.

Examples of the (meth) acrylic acid hydroxyalkyl ester include, but are not limited to, 2-hydroxyethyl (meth) acrylic acid and 2-hydroxypropyl (meth) acrylic acid.

The (poly) oxyethylene di (meth) acrylate is not limited to the following, but is, for example, di (meth) ethylene glycol di (meth) acrylate, di (meth) acrylate diethylene glycol, and di (meth) acrylic acid. Examples thereof include triethylene glycol and tetraethylene glycol di (meth) acrylate.

Specific examples of the component (b1) other than the above include, but are not limited to, glycidyl (meth) acrylate, trimethylolpropane tri (meth) acrylate, and the like.

<Component (b2): unsaturated carboxylic acid monomer>
The component (b2) component: unsaturated carboxylic acid monomer in the present embodiment is not limited to the following, but is, for example, acrylic acid, methacrylic acid, itaconic acid, and monoesters thereof, fumaric acid and monos thereof. Examples include esters, maleic acid and monoesters thereof, and it is preferable to include at least one selected from these groups.
These unsaturated carboxylic acids form an electric double layer of carbosilyl groups by making the emulsion of the present embodiment alkaline at a pH of about 7.5 to 9, as the final form of the emulsion of the present embodiment. Contributes to the mechanical stability of the particles. Furthermore, these unsaturated carboxylic acid monomers also act as catalysts for promoting the hydrolysis reaction and condensation reaction of the above-mentioned component (A).

<Component (b3): Ethylene unsaturated monomer other than component (b1) and component (b2)>
The copolymer contained in the emulsion of the present embodiment contains an ethylenically unsaturated monomer (also referred to as a (b3) component) other than the component (b1) and the component (b2) as an ethylenically unsaturated monomer. can do. The component (b3) is not limited to the following, but is copolymerized with the components (b1) and (b2) selected from, for example, an acrylamide monomer, a methacrylamide monomer, and a vinyl monomer. At least one possible comonomer can be used.

The acrylamide monomer or methacrylamide monomer is not limited to the following, and includes, for example, (meth) acrylamide, diacetone (meth) acrylamide, N-methylol (meth) acrylamide, and N-butoxymethyl ( Meta) There is acrylamide and the like, and examples of the vinyl-based monomer include vinyl acetate, vinyl propionate, vinyl versaticate, vinylpyrrolidone, methylvinyl ketone and the like.
The vinyl cyanide monomer is not limited to the following, and examples thereof include acrylonitrile and methacrylonitrile.
Further, aromatic monomers such as vinyltoluene, styrene and α-methylstyrene, vinyl halides such as vinyl chloride and vinylidene chloride, butadiene, ethylene and the like can also be mentioned.

The content ratio of the component (B) in the copolymer is preferably 65% by mass or more and 99.5% by mass or less with respect to the total of the component (A), the component (B), and the component (C). It is more preferably 70% by mass or more and 99% by mass or less, and further preferably 75% by mass or more and 98% by mass or less.
When the content ratio of the component (B) is 65% by mass or more and 99.5% by mass or less, the amount of the silanol group-containing segment tends to be controlled to less than 1 mol%, and as a result, the emulsion particles over time There is a tendency that the enlargement of the particle size is suppressed, the stability of the emulsion with time is excellent, and the deterioration of the water absorption bleaching performance can be prevented.

(Component (C): Organic silane compound having an ethylenically unsaturated group)
The copolymer contained in the emulsion of the present embodiment preferably contains an organic silane compound having an ethylenically unsaturated group as a component (C) as a monomer component.

The component (C) is not limited to the following, but is, for example, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxy. Examples thereof include propyltriethoxysilane and γ-methacryloxypropylmethyldimethoxysilane. Only one of these may be used alone, or two or more thereof may be used in combination.
The component (C) is added as a graft point in the polymer of the (B) ethylenically unsaturated monomer and is used to incorporate the component (A): an organic silane compound as a side chain.

The content ratio of the component (C) in the copolymer is preferably 0.05% by mass or more and 5% by mass or less with respect to the total of the components (A), (B), and (C). It is more preferably 0.1% by mass or more and 2.0% by mass or less, and further preferably 0.2% by mass or more and 1.5% by mass or less.
When the content ratio of the component (C) is 0.05% by mass or more and 5% by mass or less, the amount of the silanol group-containing segment tends to be controlled to less than 1 mol%, and as a result, the emulsion particles over time There is a tendency that the enlargement of the particle size is suppressed, the stability of the emulsion with time is excellent, and the deterioration of the water absorption bleaching performance can be prevented.

(Component (D): Surfactant)
The emulsion of the present embodiment preferably contains a surfactant (also referred to as component (D)) used for emulsion polymerization.
The component (D) is not particularly limited, and examples thereof include an ethylenically unsaturated monomer having a sulfonic acid group or a sulfonate group and an ethylenically unsaturated monomer having a sulfate ester group. The component (D) is an ethylenically unsaturated monomer having a sulfonic acid group or a sulfonate group and an ethylenically unsaturated monomer having a sulfate ester group from the viewpoint of achieving a high degree of water resistance of the film obtained from the emulsion. It is preferable to contain at least one of.

The ethylenically unsaturated monomer having a sulfonic acid group or a sulfonate group is a radically polymerizable double bond and a free sulfonic acid group, or a group thereof (ammonium sulfonate) which is an ammonium salt or an alkali metal salt thereof. A compound having a group or an alkali metal sulfonate group) is preferable.
The ethylenically unsaturated monomer having a sulfonic acid group or a sulfonate group is not limited to the following, but is partially substituted with, for example, a group which is an ammonium salt, a sodium salt or a potassium salt of the sulfonic acid group. It is selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, an alkyl ether group having 2 to 4 carbon atoms, a polyalkyl ether group having 2 to 4 carbon atoms, an aryl group having 6 or 10 carbon atoms and a succinic acid group. A compound having a substituent or a vinyl sulfonate compound having a vinyl group bonded to a group which is an ammonium salt, a sodium salt or a potassium salt of a sulfonic acid group is preferable.
The succinic acid compound partially substituted with a group which is an ammonium salt, a sodium salt or a potassium salt of the sulfonic acid group is not limited to the following, but is, for example, Eleminor JS-2 and JS-5 ( Product names include Sanyo Kasei Co., Ltd., Latemul S-120, S-180A, and S-180 (product name, manufactured by Kao Co., Ltd.).
Further, the compound having an alkyl ether group having 2 to 4 carbon atoms or a polyalkyl ether group having 2 to 4 carbon atoms, which is an ammonium salt, a sodium salt or a potassium salt of a sulfonic acid group, is not limited to the following. However, for example, Aqualon HS-10 (product name, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), Adecaria Soap SE-1025A, SR-10N, SR-20N (product name, manufactured by ADEKA Corporation), Aqualon KH- 10 (product name, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and the like can be mentioned.

The component (D) may be present in the emulsion as a copolymer radically polymerized on the emulsion particles, may be adsorbed on the emulsion particles as an unreacted product, or may be present in the aqueous emulsion phase, or It may be adsorbed on emulsion particles as a copolymer with a water-soluble monomer or a copolymer between ethylenically unsaturated monomers used as a surfactant, or may be present in the emulsion aqueous phase as the copolymer. ..
In particular, by increasing the proportion of the ethylenically unsaturated monomer used as (D) surfactant in the state of a copolymer radically polymerized into emulsion particles, the water resistance of the film obtained from the emulsion can be improved. Tends to be able to.

For the ethylenically unsaturated monomer used as the component (D), each substance should be identified by performing pyrolysis gas chromatogram mass spectrometry (Py-GC-MS) of the film obtained from the emulsion of the present embodiment. Can be done. As another method, it can be identified by separating the aqueous phase component of the emulsion of the present embodiment and then performing fast atom bombardment mass spectrometry (FAB mass spectrometry).
In the emulsion of the present embodiment, the amount of the ethylenically unsaturated monomer used as the component (D) is preferably 0.05 with respect to the total mass of the component (B): the ethylenically unsaturated monomer. It is by mass% or more and 10% by mass or less, and more preferably 0.1% by mass or more and 5% by mass or less.

In the present embodiment, as the surfactant, other ordinary surfactants other than the ethylenically unsaturated monomer having a sulfonic acid group, a sulfonate group, or a sulfate ester group can also be used in combination.
The surfactant is not limited to the following, but is, for example, an anion type such as fatty acid soap, alkyl sulfonate, alkyl sulfosuccinate, polyoxyethylene alkyl sulfate, and polyoxyethylene alkyl aryl sulfate. Surfactants; polyoxyethylene alkyl ethers such as Emargen 120, Emargen 150 (product name, manufactured by Kao Co., Ltd.), Newcol 2399S (product name, manufactured by Nippon Surfactant Co., Ltd.); polyoxyethylene sorbitan fatty acid ester , Oxyethylene oxypropylene block copolymer and other non-reactive nonionic surfactants, Adecaria soap NE-20, NE-30, NE-40 (product name, manufactured by Asahi Denka Kogyo Co., Ltd.), etc. α- [1 -[(Allyloxy) methyl] -2- (nonylphenoxy) ethyl] -ω-hydroxypolyoxyethylene; and Aqualon RN-10, RN-20, RN-30, RN-50 (product name, Daiichi Kogyo Seiyaku Co., Ltd. Examples thereof include reactive nonionic surfactants such as polyoxyethylene alkylpropenylphenyl ether manufactured by Co., Ltd.), which are copolymerizable with ethylenically unsaturated monomers.

The amount of the surfactant other than the surfactant containing the ethylenically unsaturated monomer described above is (B) with respect to the total mass (100% by mass) of the ethylenically unsaturated monomer. D) When the surfactant is an anionic surfactant, it is preferably 0.5% by mass or less, more preferably 0.25% by mass or less, a non-reactive nonionic surfactant and a reactive nonionic surfactant. In the case of an activator, it is preferably 2.0% by mass or less, more preferably 1.0% by mass or less. By using it in this range, a film having better water resistance tends to be formed.

((E) component: catalyst)
The emulsion of the present embodiment preferably contains a catalyst (also referred to as component (E)).
The catalyst preferably contains a poorly water-soluble acid catalyst. Examples of the poorly water-soluble acid catalyst include anthracene sulfonic acid, anthraquinone sulfonic acid, phenanthrene sulfonic acid, pyrene sulfonic acid, coronen sulfonic acid, dinonylnaphthalene (mono) sulfonic acid perylene sulfonic acid, pyrenedi sulfonic acid, and phenanthrange sulfonic acid. , Aromatic hydrocarbon sulfonic acid such as dinonylnaphthalenedisulfonic acid, scandium dodecyl sulfate and the like. These may be used individually by 1 type, and may be used in combination of 2 or more type. Of these, dinonylnaphthalene (mono) sulfonic acid is preferable. By using a poorly water-soluble acid catalyst, the amount of the silanol group-containing segment tends to be controlled to less than 1 mol%, and as a result, the enlargement of the particle size of the emulsion particles over time is suppressed, and the emulsion over time is suppressed. It has excellent stability and tends to prevent deterioration of water absorption and whitening performance.

The content of the poorly water-soluble acid catalyst is preferably 0.01% by mass or more and 2.0% by mass or less with respect to the total mass (100% by mass) of the component (B): ethylenically unsaturated monomer. , More preferably 0.1% by mass or more and 1.0% by mass or less. By setting the content of the poorly water-soluble acid catalyst to 0.01% by mass or more and 2.0% by mass or less, the amount of the silanol group-containing segment tends to be controlled to less than 1 mol%.

Conventionally, as a usual acid catalyst for adjusting the pH to 2.4 or less, methacrylic acid, acrylic acid, sulfuric acid, hydrochloric acid, dodecylbenzenesulfonic acid, methanesulfonic acid, p-toluenesulfonic acid, 2,6-naphthalenedisulfonic acid, A water-soluble strong acid such as acid, 2,7-naphthalenedisulfonic acid, 2-naphthalenesulfonic acid, 1-naphthalenesulfonic acid, butylnaphthalenesulfonic acid, dodecylnaphthalenesulfonic acid, and camphorsulfonic acid is used. In addition to these ordinary acid catalysts, it is preferable to use a catalyst which is a poorly water-soluble acid catalyst in combination.

The content of component (E), which is a combination of a poorly water-soluble acid catalyst and a normal acid catalyst, is based on the total mass (100% by mass) of component (B): ethylenically unsaturated monomer. It is preferably 0.01% by mass or more and 2.5% by mass or less, and more preferably 0.1% by mass or more and 1.5% by mass or less. By setting the content of the component (E) to 0.01% by mass or more and 2.5% by mass or less, the silanol group-containing segment content tends to be controlled to less than 1 mol%.

(UV absorber, light stabilizer)
The emulsion of this embodiment may contain a UV absorber and / or a light stabilizer.
High weather resistance can be imparted by containing an ultraviolet absorber and / or a light stabilizer.
As a method of incorporating the ultraviolet absorber and / or the light stabilizer in the emulsion of the present embodiment, it is preferable that the ultraviolet absorber and / or the light stabilizer is present at the time of emulsion polymerization.
When the ultraviolet absorber and / or the light stabilizer is allowed to be present at the time of emulsion polymerization, excellent dispersibility is obtained, and the ultraviolet absorber and / or the light stabilizer are dispersed and present in the coating film using the emulsion of the present embodiment. It is preferable that elution is prevented due to rainfall or the like and durability is improved over a long period of time.
The timing of blending the ultraviolet absorber and / or the light stabilizer is arbitrary, and it may be present at the time of emulsion polymerization.

The ultraviolet absorber and / or light stabilizer is preferably used in an amount of 0.1% by mass to 5% by mass with respect to the total mass of the component (B): ethylenically unsaturated monomer. By setting the amount of the ultraviolet absorber and / or light stabilizer to 0.1% by mass or more, the effect of improving durability can be sufficiently exhibited, and by setting it to 5% by mass or less, the polymerization stability can be improved. It can be kept good and the water resistance of the coating film can be made good.

Further, as the ultraviolet absorber, a radical-polymerizable one having a radical-polymerizable double bond in the molecule, and as a light stabilizer, a radical-polymerizable one having a radical-polymerizable double bond in the molecule shall be used. You can also do it.

Further, it is preferable to use an ultraviolet absorber and a light stabilizer in combination because the coating film has particularly excellent weather resistance when forming a coating film using the emulsion.

The ultraviolet absorber is not limited to the following, and examples thereof include at least one selected from benzophenone type, benzotriazole type, and triazine type.
Examples of the light stabilizer include at least one selected from the hindered amine type.
By combining a highly durable polysiloxane-containing highly weather-resistant emulsion with a benzophenone-based, benzotriazole-based, triazine-based UV absorber, and hindered amine-based light stabilizer, which have high UV absorption capacity, these synergistic effects are superior. Shows durability.
The benzophenone-based ultraviolet absorber is not limited to the following, and is, for example, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid. , 2-Hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-n-dodecyloxybenzophenone, 2-hydroxy-4-benzyloxybenzophenone, bis (5-benzoyl-4-hydroxy-2-methoxyphenyl) ) Methan, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'dimethoxybenzophenone, 2,2', 4,4'-tetrahydroxybenzophenone, 4-dodecyloxy-2- Examples thereof include hydroxybenzophenone, 2-hydroxy-4-methoxy-2'-carboxybenzophenone, 2-hydroxy-4-stearyloxybenzophenone and the like.
Benzotriazole-based ultraviolet absorbers are not limited to the following, but are, for example, 2- (2'-hydroxy-5'-methylphenyl) benzotriazole and 2- (2'-hydroxy-5'-. tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-3', 5'-di-tert-butylphenyl) benzotriazole, 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 2 -(2-Hydroxy-3,5-di-tert-octylphenyl) benzotriazole, 2- [2'-hydroxy-3', 5'-bis (α, α'-dimethylbenzyl) phenyl] benzotriazole), Methyl-3- [3-tert-butyl-5- (2H-benzotriazole-2-yl) -4-hydroxyphenyl] A condensate of propionate and polyethylene glycol (molecular weight 300) (manufactured by BASF Co., Ltd., product name) : TINUVIN1130), Isooctyl-3- [3- (2H-benzotriazole-2-yl) -5-tert-butyl-4-hydroxyphenyl] propionate (manufactured by BASF Co., Ltd., product name: TINUVIN384), 2- ( 3-Dodecyl-5-methyl-2-hydroxyphenyl) Benzotriazole (manufactured by BASF Co., Ltd., product name: TINUVIN571), 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl)- 5-Chlorobenzotriazole, 2- (2'-hydroxy-3', 5'-di-tert-amylphenyl) benzotriazole, 2- (2'-hydroxy-4'-octoxyphenyl) benzotriazole, 2- [2'-Hydroxy-3'-(3'', 4'', 5'', 6''-tetrahydrophthalimidemethyl) -5'-methylphenyl] Benzotriazole, 2,2-methylenebis [4- (1) , 1,3,3-Tetramethylbutyl) -6- (2H-benzotriazole-2-yl) phenol], 2- (2H-benzotriazole-2-yl) -4,6-bis (1-methyl-) 1-Phenylethyl) phenol (manufactured by BASF Co., Ltd., product name: TINUVIN 900) and the like can be mentioned.

The radically polymerizable benzotriazole-based ultraviolet absorber is not limited to the following, but is, for example, 2- (2'-hydroxy-5'-methacryloxyethylphenyl) -2H-benzotriazole (Otsuka Kagaku (Otsuka Chemicals). Made by Co., Ltd., Product name: RUVA-93), 2- (2'-hydroxy-5'-methacryloxyethyl-3-tert-butylphenyl) -2H-benzotriazole, 2- (2'-hydroxy-5' − Methacryloxypropyl-3-tert-butylphenyl) -5-chloro-2H-benzotriazole, 3-methacryloyl-2-hydroxypropyl-3- [3'-(2''-benzotriazolyl) -4 -Hydroxy-5-tert-butyl] phenylpropionate (manufactured by BASF Co., Ltd., product name: CGL-104) and the like can be mentioned.

The triazine-based ultraviolet absorber is not limited to the following, and examples thereof include TINUVIN400 (product name, manufactured by BASF Limited).

As the hindered amine-based light stabilizer, those having low basicity are preferable, and specifically, those having a base constant (pKb) of 8 or more are preferable.
The hindered amine-based photostabilizer is not limited to the following, and includes, for example, bis (2,2,6,6-tetramethyl-4-piperidyl) succinate and bis (2,2,6,6-tetra). Methylpiperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) 2- (3,5-di-tert-butyl-4-hydroxybenzyl) -2-butylmalonate, 1- [2- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propynyloxy] ethyl] -4- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propynyl Oxy] -2,2,6,6-tetramethylpiperidine, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate and methyl-1,2,2,6,6-pentamethyl-4 -Piperidyl-sevacate mixture (manufactured by BASF Co., Ltd., product name: TINUVIN292), bis (1-octoxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, TINUVIN123 (product name, BASF Co., Ltd.) ), Etc.

[Emulsion manufacturing method]
In the emulsion of the present embodiment, the hydrolysis-condensation reaction of the component (A), the addition polymerization reaction of the component (B), the hydrolysis-condensation reaction and the addition polymerization reaction of the component (C), and the presence of the component (E) It can be produced by a production method including a step performed below (hereinafter, also referred to as a polymerization step).
The above-mentioned production method preferably further includes a step of removing the by-product alcohol and a heat treatment step of heating at pH 10 or higher to carry out a condensation reaction of the component (A).

(Polymerization process)
Examples of the polymerization method used in the polymerization step in the method for producing an emulsion of the present embodiment include emulsion polymerization, suspension polymerization, massive polymerization, and mini-emulsion polymerization. Among these polymerization methods, emulsion polymerization is preferable from the viewpoint of stably producing an emulsion having an average particle size of about 10 nm to 1 μm and having good dispersion stability.

As a method for producing an emulsion of the present embodiment to which emulsion polymerization is applied, for example,
After polymerizing a pre-emulsifying solution consisting of a component (B): an ethylenically unsaturated monomer and a component (D): a surfactant in an aqueous medium, the component (A): an organic silane represented by the formula (1) Compound and component (C): A method of mixing an organic silane compound having an ethylenically unsaturated group and carrying out a hydrolysis and condensation reaction;
First, a component (A): an organic silane compound represented by the formula (1) and a component (C): an organic silane compound having an ethylenically unsaturated group are mixed and subjected to a hydrolysis and condensation reaction, and then (B). ) Component: Ethylene unsaturated monomer and component (D): Method of adding and polymerizing a pre-emulsifying solution containing a surfactant;
And so on.
In particular, a pre-emulsified solution composed of (B) an ethylenically unsaturated monomer and (D) a surfactant was mixed with (A) an organic silane compound and (C) an organic silane compound having an ethylenically unsaturated group. Later, a method in which the polymerization reaction, the hydrolysis and the condensation reaction are carried out in parallel in an aqueous medium is preferable from the viewpoint of homogenizing the organic component and the polysiloxane component.
As the aqueous medium used in the polymerization step, water is mainly used, which is introduced into the reaction system, and a water-soluble solvent such as a lower alcohol having 1 to 3 carbon atoms or acetone is added to the water. It may be an aqueous medium. The amount of the solvent other than water added at this time is preferably 20% by mass or less in the emulsion. Here, the amount of the water-soluble solvent in the aqueous medium used for the emulsion is preferably 5% by mass or less, more preferably 2% by mass or less of the aqueous medium, and contains a water-soluble solvent. It is even more preferable that there is no such thing. When the amount of the solvent soluble in water is 20% by mass or less, the emulsified state of the pre-emulsified liquid is well maintained, and it tends to show good polymerization stability.

In emulsion polymerization, a water-soluble or oil-soluble persulfate or peroxide that can be radically decomposed by a heat or a reducing substance to cause addition polymerization of an ethylenically unsaturated monomer as a radical polymerization catalyst. , Azobis compound and the like can be advantageously used.
The radical polymerization catalyst is not particularly limited, but for example, potassium persulfate, sodium persulfate, ammonium persulfate, hydrogen peroxide, t-butyl hydroperoxide, t-butyl peroxybenzoate, 2,2-. Examples thereof include azobisisobutyronitrile, 2,2-azobis (2-diaminopropane) hydrogen peroxide, and 2,2-azobis (2,4-dimethylvaleronitrile). Among these, potassium persulfate, sodium persulfate, and ammonium persulfate are preferable.

The amount of the radical polymerization catalyst used is preferably 0.05% by mass or more and 1.0% by mass or less with respect to the total mass of the component (B): ethylenically unsaturated monomer.

The component (E): catalyst and pH at the time of polymerization in the polymerization step are important for adjusting so that the hydrolysis and condensation reaction of the component (A) proceeds rapidly and the amount of the silanol group-containing segment is suppressed. ..
In the method for producing an emulsion of the present embodiment, it is preferable to use a poorly water-soluble acid catalyst and a normal acid catalyst in combination, and to set the pH of the polymerization reaction system in the range of 1.5 or more and 2.4 or less.
When the pH is 1.5 or more, the hydrolysis of the component (A) proceeds slowly, an increase in the by-product alcohol concentration can be prevented, and the polymerization stability tends to be maintained well. As the acid catalyst for adjusting the pH to 1.5 or more, it is preferable to use the strong acid which is the usual acid catalyst.
By using a poorly water-soluble acid catalyst and setting the pH to 2.4 or less, the condensation reaction rate of the component (A) can be adjusted within a suitable range, and the uncondensed silanol groups in the emulsion can be reduced for production. The silanol group-containing segment content of the obtained emulsion can be adjusted to less than 1 mol%, and there is a tendency that the phenomenon of particle size enlargement and the increase in viscosity with time can be prevented.

The polymerization reaction is preferably carried out under normal pressure at a polymerization temperature of 65 to 90 ° C., but can also be carried out under high pressure according to the characteristics such as vapor pressure at the polymerization temperature of the monomer.
The polymerization time includes an introduction time and a cooking time after introduction. The introduction time is usually several minutes when various raw materials are introduced into the reaction system at the same time, and when various raw materials are sequentially introduced into the reaction system, they are sequentially introduced into the reaction system within a range in which heat generation due to polymerization can be removed. It usually takes 10 minutes or more, although it depends on the concentration of the polymer in the finally obtained emulsion.
The aging (cooking) time after introduction is preferably 10 minutes or more.
Below this polymerization time, each raw material may remain as it is, or the organic silane compound may remain as a hydrolyzate without condensation.
When it is desired to accelerate the polymerization rate and polymerize at a low temperature of 70 ° C. or lower, for example, a reducing agent such as sodium bisulfite, ferrous chloride, ascorbic acid salt, or longalite may be used in combination with a radical polymerization catalyst. It is advantageous.
Furthermore, it is also possible to optionally add a chain transfer agent such as dodecyl mercaptan to adjust the molecular weight of the emulsion.

Further, as a curing catalyst at the time of film formation after the completion of emulsification polymerization, for example, dibutyltin dilaurate, dioctyltin dilaurate, dibutyltin diacetate, tin octylate, tin laurate, iron octylate, lead octylate, tetrabutyl titanate and the like Metallic salts of organic acids; n-hexylamine, 1,8-diazabicyclo [5,4,0] -7-undecene and other amine compounds are preferably added to the emulsion of this embodiment.
When these curing catalysts are not water-soluble, it is preferable to emulsify them with a surfactant and water when using them.

As an embodiment for producing the emulsion of the present embodiment, component (B): emulsion polymerization by radical polymerization of an ethylenically unsaturated monomer and component (A): an organic silane compound represented by the formula (1). The emulsion polymerization by the hydrolysis and the condensation reaction of the above is simultaneously carried out in an aqueous medium, and the hydrolysis condensate of the component (A) and the polymer of the component (B) are in a uniform state, forming a state in which the composition is less unevenly distributed. It is preferable to do so.
The emulsion polymerization method to be applied is not particularly limited, and may be any one of a one-step polymerization method for forming a uniform structure, a multi-step polymerization method capable of forming a core-shell structure, and the like, and a polymerization method according to the purpose can be selected. be.

Hereinafter, for example, a case where emulsion polymerization is carried out in two stages will be described.
Component (B): Ethylene in which the ethylenically unsaturated monomers contains the same or different component compositions (B1) and (B2), and component (D): the surfactant has a sulfonic acid group or a sulfonate group. When selected from the group consisting of sex-unsaturated monomers, ethylenically unsaturated monomers having a sulfate ester group, and mixtures thereof, and containing the same or different surfactants (D1) and (D2) from each other. It is preferable that the emulsion polymerization is carried out in the order of step [1] and step [2].
In step [1], a pre-emulsifying solution containing an ethylenically unsaturated monomer composition (B1), a surfactant (D1) and, if necessary, an aqueous medium is subjected to emulsion polymerization in the aqueous medium. , Obtain the emulsion in step [1].
In step [2], a pre-emulsified solution containing an ethylenically unsaturated monomer composition (B2) and a surfactant (D2) and, if necessary, an aqueous medium is added to the emulsion in step [1] in the aqueous medium. Emulsion polymerization is carried out by adding to, and if necessary, a pre-emulsifying solution, component (A): an organic silane compound represented by the formula (1), and component (C): an organic silane having an ethylenically unsaturated group. By subjecting the compound to emulsion polymerization while mixing it, an emulsion in which polysiloxane is compounded can be produced.

(Heat treatment process)
In the method for producing an emulsion of the present embodiment, the hydrolysis-condensation reaction of the component (A), the addition polymerization reaction of the component (B), and the hydrolysis-condensation and addition polymerization reaction of the component (C) are combined with the component (E). After the polymerization step performed in the presence of the above, in order to promote the condensation of uncondensed silanol groups in the emulsion, the mixture is heated at pH 10 or higher (also referred to as alkaline heat treatment) to carry out the condensation reaction of the component (A). Is preferable.
The heating temperature is preferably 80 to 90 ° C.
The pH at the time of the alkaline heat treatment in the present embodiment is preferably 10.0 or more, more preferably 10.2 or more, still more preferably 10.3 or more.
When the pH is 10.0 or higher, the condensation reaction rate of the uncondensed silanol groups in the emulsion becomes sufficient, the treatment time for obtaining the silanol group-containing segment amount can be shortened, and the productivity tends to be improved. ..
Further, from the viewpoint of reducing the production cost without increasing the amount of the alkaline component used exponentially, the pH at the time of the alkaline heat treatment is preferably 11.0 or less, and more preferably 10.8 or less. It is preferably 10.6 or less, and more preferably 10.6 or less.

The silanol group condensation reaction proceeds in the acidic or alkaline region. During emulsion polymerization, condensation of silanol groups is promoted in a strongly acidic region of pH 2.5 or less, and after completion of emulsion polymerization, condensation of uncondensed silanol groups is promoted in a strongly alkaline region of pH 10 or more. That is, it is possible to promote the condensation of silanol groups by adjusting the acidic state and the alkaline state in two steps.
As described above, by promoting the condensation ^{of silanol groups, the amount of silanol group-containing segments of component (A) identified and quantified by the 29} Si solid-state NMR spectrum is the total amount of segments derived from the silicone structure of component (A). It tends to be suppressed to less than 1 mol%, and it is possible to provide an emulsion having stable characteristics with no particle size enlargement over time and no increase in viscosity as compared with the conventional polysiloxane-containing polymer emulsion. It becomes.

In the method for producing an emulsion of the present embodiment, it is preferable to remove the alcohol produced as a by-product during the hydrolysis of the component (A). The by-produced alcohol may be removed either after the above-mentioned polymerization step or after the heat treatment step in an alkaline state having a pH of 10 or higher.
The method for removing the by-produced alcohol is not limited to the following, and examples thereof include a general-purpose distillation treatment and a stripping treatment in which vapor is aerated in the emulsion.
The residual alcohol concentration after removing the by-produced alcohol is preferably 0.1% by mass to 2% by mass or less. By setting the residual alcohol concentration to 0.1% by mass or more, it is not necessary to excessively increase the amount of distilled water, and there is a tendency that an increase in production load and production cost can be prevented. By setting the residual alcohol concentration to 2% by mass or less, ignition of the emulsion tends to be prevented.

[Use of emulsion]
The emulsion of the present embodiment is useful as a finishing material for paints and building materials, or as a finishing material for woven fabrics and non-woven fabrics.
In particular, as finishing materials for paints and building materials, specifically, inorganic building materials such as concrete, cement mortar, slate board, caucal board, plaster board, extruded board, foamable concrete, woven cloth or non-woven fabric are used as base materials. Main material and top coat material for multi-layer finish coating material, thin finish coating material, thick finish coating material, stone-like finishing material, gloss as paint or building finishing material for various base materials such as building materials and metal building materials. It is useful as synthetic resin emulsion paint such as paint, metal paint, wood paint, and tile paint.
Further, the emulsion of the present embodiment is also useful as a binder or a protective layer for a photocatalytic paint because of its high siloxane binding energy.

Hereinafter, the present embodiment will be described with reference to specific examples and comparative examples, but the present embodiment is not limited to the examples described later.
The evaluation of the polymerization stability and the test of the physical properties of the obtained polysiloxane-containing aqueous acrylate polymer emulsion were carried out according to the evaluation method and the test method shown below.

<(1) Evaluation of polymerization stability>
The coagulated product of the emulsion obtained after emulsion polymerization was filtered through a 100-mesh filter cloth, the residue ratio was determined from the ratio of the residue mass to the solid content mass of the emulsion, and the polymerization stability was evaluated according to the following criteria.
(Judgment criteria) ◎: Residue ratio is less than 100 ppm
◯: Residue ratio is 100 ppm or more and less than 200 ppm
X: Residue rate is 200 ppm or more

<(2) Evaluation of filterability>
The emulsion obtained after emulsion polymerization was filtered through a 100-mesh filter cloth to measure the time required for completion, and the filterability was evaluated according to the following criteria.
(Judgment criteria) ◎: Filtration time is less than 30 seconds
◯: Filtration time is 30 seconds or more and less than 60 seconds
×: Filtration time is 60 seconds or more

<(3) Measurement of volume average particle size>
The volume average particle size of the obtained emulsion was measured with a Microtrack particle size distribution meter manufactured by Leeds & North Wrap.

<(4) Quantitative analysis of silanol group-containing segments>
The amount of silanol group-containing segments in the obtained emulsion is obtained by freeze-drying the emulsion and ^{measuring by 29} Si solid-state NMR measurement (DD / MAS method) under the following conditions. Using the values, it was calculated using the formula (2), specifically, the following formula (2-1).
Equipment: Bruker Biospin DSX400
Observation nucleus: ²⁹ Si
Frequency: 79.48MHz
Measurement method: DD / MAS method Waiting time: 30 sec
NMR sample tube: 7 mmφ
Number of integrations: 7600 times MAS: 4900Hz
Chemical shift criteria: TMS (CHCl ₃ solution)

<(5) Viscosity>
The viscosity of the obtained emulsion was measured with a B-type viscometer (manufactured by Toki Sangyo Co., Ltd .: Viscometer TVB-10).

<(6) Measurement of solid content>
To measure the solid content, 1 g of the obtained emulsion was precisely weighed in an aluminum dish, dried in a constant temperature dryer at 105 ° C. for 3 hours, allowed to cool in a desiccator containing silica gel for 30 minutes, and then finely weighed. did. The ratio obtained by dividing the mass after drying by the mass before drying was defined as the solid content ratio (mass%).
The solid content was measured after the completion of emulsion polymerization and after the by-product alcohol was removed by distillation and concentration treatment, respectively, and used as the post-polymerization solid content and the final solid content.

<(7) Evaluation of stability over time>
The stability over time was evaluated by storing the obtained emulsion in a constant temperature bath at 60 ° C. for 4 weeks, and comparing the increase rate of the volume average particle size before and after the storage test with the increase / decrease rate of the viscosity.
Specifically, for the particle size stability over time, the volume average particle size of each emulsion before the storage test was measured with a Microtrack particle size distribution meter manufactured by Leeds & North Wrap, and each emulsion was placed in a constant temperature bath at 60 ° C. 4 It was stored for a week, the volume average particle size before and after the storage test was measured, and the rate of increase was evaluated according to the following criteria.
For the viscosity stability over time, the 60 rpm viscosity of each emulsion before the storage test was measured with a B-type viscometer (Toki Sangyo Co., Ltd .: Viscometer TVB-10), and each emulsion was placed in a constant temperature bath at 60 ° C for 4 weeks. After storage, the rate of increase / decrease in viscosity before and after the storage test was evaluated according to the following criteria.
((7-1) Criteria for determining particle size stability over time)
◎: Increase in particle size is less than 5%
◯: Increase in particle size is 5% or more and less than 10%
Δ: Increase in particle size is 10% or more and less than 30%
X: Increase in particle size by 30% or more ((7-2) Criteria for determining viscosity stability over time)
◎: Viscosity increase or decrease is less than 5%
◯: Increase or decrease in viscosity is 5% or more and less than 10%
Δ: Increase or decrease in viscosity is 10% or more and less than 50%
X: Increase or decrease in viscosity is 50% or more

<(8) Water absorption whitening performance evaluation>
For the evaluation of water absorption and whitening performance, a coating film was obtained by applying the emulsion paint obtained on a glass plate with a 0.1 mm applicator and drying at 23 ° C. overnight. Then, the glass plate was immersed in water at 23 ° C. for 24 hours with the coating film adhered.
The rate of change (rate of change in haze value) between the transmittance and haze value before immersion and the transmittance and haze value after immersion was measured with a haze meter NDH5000 manufactured by Nippon Denshoku Kogyo Co., Ltd.
For the judgment, a coating film was prepared from each of the emulsions before and after the storage test described in <Evaluation of stability over time> described in (7) above, and the rate of change in haze value due to water absorption and whitening was compared.
⊚: Difference in haze value change rate before and after storage test is less than ± 2.5% ○: Haze value change rate after storage test increased by 2.5% or more and less than 5% compared to before storage test △ : The rate of change in haze value after the storage test increased by 5% or more and less than 10% compared to before the storage test, and the water absorption and whitening resistance deteriorated. ×: The haze value after the storage test increased by 10% or more compared to before the storage test. However, the water absorption and whitening resistance deteriorates.

[Example 1]
730 parts by mass of water and Aqualon KH-10 (product name, Daiichi Kogyo Seiyaku Co., Ltd.) as a surfactant in a 2.0-liter SUS separable flask equipped with a stirrer, reflux condenser, dropping tank and thermometer. 16 parts by mass of a 25% by mass aqueous solution (manufactured by Co., Ltd.) was charged, and 5 minutes after raising the temperature to 80 ° C., 7.5 parts by mass of a 2% by mass aqueous solution of ammonium peroxosulfate was added.

Next, as step (1), component (B): 25 parts by mass of cyclohexyl methacrylate (CHMA), 66 parts by mass of butyl methacrylate (BMA), 69 parts by mass of methyl methacrylate (MMA), which is an ethylenically unsaturated monomer. Parts, 87.5 parts by mass of butyl acrylate (BA), 2.5 parts by mass of methacrylate (MAA), component (E): 0.5 parts by mass of dinonylnaphthalene (mono) sulfonic acid, and an aqueous solution as an initiator. 12.5 parts by mass of a 2% aqueous solution of ammonium sulfate (APS), 20 parts by mass of a 25% by mass aqueous solution of surfactant: Aqualon KH10, and 12 parts of a 20% aqueous solution of Emalgen (Em150) (product name, manufactured by Kao Co., Ltd.) .5 parts by mass, acid catalyst: A mixed solution of 15 parts by mass of a 10% aqueous solution of dodecylbenzene sulfonic acid (DBS) and 218 parts by mass of water was prepared, and the mixed solution was emulsified with a homomixer to obtain a pre-emulsified solution. ..
Next, as the component (A), 33 parts by mass of methyltrimethoxysilane Z6366 (product name, manufactured by Toray Dow Corning Co., Ltd.), 20 parts by mass of dimethyldimethoxysilane Z6329 (product name, manufactured by Toray Dow Corning Co., Ltd.), Phenyltrimethoxysilane KBM103 (product name, manufactured by Shin-Etsu Silicone Co., Ltd.) 13.5 parts by mass, and (C) γ-methacryloxypropyltrimethoxysilane SZ6030 (product name) as an organic silane compound having an ethylenically unsaturated group. , Toray Dow Corning Co., Ltd.) 2.5 parts by mass of the mixed solution and the pre-emulsified solution obtained as described above in a Y-shaped tube [The outlet of the Y-shaped tube is filled with a 100 mesh wire mesh 2 Fill with Molecular Sives 3A (product name: manufactured by Wako Pure Chemical Industries, Ltd.) until the liquids in the dropping tank are mixed so that (A) the organic silane compound component and the pre-emulsified liquid can be gently mixed. It was adjusted. ], It was allowed to flow into the reaction vessel from the dropping tank over 2 hours.
The temperature in the reaction vessel was kept at 80 ° C. during the inflow.
After the inflow was completed, the temperature in the reaction vessel was maintained at 80 ° C. for 30 minutes.

Next, as step (2), the component (B): cyclohexyl methacrylate 25 parts by mass, butyl methacrylate 56.5 parts by mass, methyl methacrylate 136 parts by mass, butyl acrylate 22. 5 parts by mass, hydroxyethyl methacrylate 2.5 parts by mass, 5 parts by mass methacrylic acid, 2.5 parts by mass acrylate, component (E): dinonylnaphthalene (mono) sulfonic acid 0.5 parts by mass, ammonium persulfate A mixed solution of 15 parts by mass of a 2% by mass aqueous solution of AQUARON KH10, 8 parts by mass of a 25% by mass aqueous solution of Aqualon KH10, 15 parts by mass of a 10% by mass aqueous solution of dodecylbenzenesulfonic acid, and 222 parts by mass of water was prepared, and the mixed solution was homogenized. It was emulsified with a mixer to obtain a pre-emulsified solution.
Next, as the (A) organic silane compound component, 33 parts by mass of methyltrimethoxysilane, 20 parts by mass of dimethyldimethoxysilane, 13.5 parts by mass of phenyltrimethoxysilane, and 2.5 parts by mass of γ-methacryloxypropyltrimethoxysilane. The mixed solution of the part and the pre-emulsifying solution obtained as described above were allowed to flow into the reaction vessel from the dropping tank over 1 hour.
During the inflow, the temperature in the reaction vessel was kept at 80 ° C., and even after the inflow was completed, the temperature in the reaction vessel was kept at 80 ° C. for 60 minutes, and then cooled to room temperature to complete the emulsion polymerization.
The hydrogen ion concentration of the obtained emulsion was measured and found to have a pH of 2.3 and a solid content of 32.9% by mass.
The dry mass of the agglomerates filtered through a 100-mesh wire mesh was very small, 20 ppm or less with respect to the obtained solid content mass, and the deposits on the inner wall of the reaction vessel and the stirring blade were also small. ..
Subsequently, in order to promote the condensation of uncondensed silanol groups in the obtained emulsion, 1 kg of the above emulsion was charged into a 2 L eggplant flask, and then 35 g of a 25 mass% aqueous ammonia solution was added. The pH was 10. It was 2.
Then, the emulsion was immersed in a water bath of an evaporator device to bring the temperature of the emulsion to 80 ° C., and then the eggplant flask was kept rotating for 5 hours.
Next, an appropriate amount of defoaming agent was added, and the pressure was gradually reduced to 40 kPa at the end of the pressure reduction, and distillation and concentration treatment were carried out until the methanol concentration reached 0.8% by mass.
After cooling to room temperature, the emulsion was filtered through a 100-mesh wire mesh, and the hydrogen ion concentration was measured and found to be pH 7.8. A 25 mass% aqueous ammonia solution was added thereto to adjust the pH to 8.7.
The solid content of the obtained emulsion was 40.2% by mass, the volume average particle size was 105 nm, and the viscosity was 650 mPa · s.

[Example 2]
The emulsion was produced by the same method as in Example 1 except that the raw materials for producing the emulsion were the formulations shown in Table 2 below.
The solid content, volume average particle size, and viscosity of the obtained emulsion are shown in Table 3 below.

[Example 3]
The raw materials for producing the emulsion were the formulations shown in Table 2 below, and steps (2) were carried out in the same manner as in Example 1.
Next, as step (3), a pre-emulsified solution is prepared from the component (B), the component (D), the catalyst and water in parts of the mass shown in Table 2 below, and the pre-emulsified solution is combined with the mixed solution of the component (A) and the component (C). The obtained pre-emulsified solution was allowed to flow into the reaction vessel from the dropping tank over 1 hour.
During the inflow, the temperature in the reaction vessel was kept at 80 ° C., and even after the inflow was completed, the temperature in the reaction vessel was kept at 80 ° C. for 60 minutes, and then cooled to room temperature to complete the emulsion polymerization.
Then, in the same manner as in Example 1, in order to promote the condensation of uncondensed silanol groups in the obtained emulsion, 1 kg of the above emulsion was charged into a 2 L eggplant flask, and then 35 g of a 25 mass% ammonia aqueous solution was added. However, the pH was 10.4.
Further, in the same manner as in Example 1, the emulsion was immersed in a water bath of an evaporator device to bring the temperature of the emulsion to 80 ° C., and then the eggplant flask was kept rotating for 5 hours, followed by distillation and concentration treatment.
The solid content, volume average particle size, and viscosity of the obtained emulsion are shown in Table 3 below.

[Example 4]
In a separable flask made of SUS with an internal capacity of 2.0 liters equipped with a stirrer, a reflux condenser, a dropping tank, and a thermometer, 680 parts by mass of water and 16.8 mass of a 25 mass% aqueous solution of Aqualon KH10 as a surfactant 5 minutes after the temperature was raised to 80 ° C., 10.5 parts by mass of a 2% by mass aqueous solution of ammonium peroxosulfate was added.
Next, an emulsion was prepared by performing the same treatment as in Example 1 except that the raw materials were formulated as shown in Table 2 below.
The solid content, volume average particle size, and viscosity of the obtained emulsion are shown in Table 3 below.

[Example 5]
In a separable flask made of SUS with an internal capacity of 2.0 liters equipped with a stirrer, a reflux condenser, a dropping tank, and a thermometer, 730 parts by mass of water and 16.0 mass by mass of a 25 mass% aqueous solution of Aqualon KH10 as a surfactant. 5 minutes after the temperature was raised to 80 ° C., 7.5 parts by mass of a 2% by mass aqueous solution of ammonium peroxosulfate was added.
Next, an emulsion was prepared by performing the same treatment as in Example 1 except that the raw materials were formulated as shown in Table 2 below.
The solid content, volume average particle size, and viscosity of the obtained emulsion are shown in Table 3 below.

[Comparative Example 1]
440 parts by mass of water and a 25% by mass aqueous solution of Aqualon KH-10 as a surfactant in a 2.0-liter SUS separable flask equipped with a stirrer, a reflux condenser, a dropping tank, and a thermometer. After adding 0 parts by mass and raising the temperature to 80 ° C., 4.5 parts by mass of a 2% by mass aqueous solution of ammonium peroxosulfate was added.
Next, an emulsion was prepared by performing the same treatment as in Example 1 except that the raw materials were formulated as shown in Table 2 below.
The solid content, volume average particle size, and viscosity of the obtained emulsion are shown in Table 3 below.

[Comparative Example 2]
An emulsion was produced by performing the same treatment as in Example 1 except that the raw materials were formulated as shown in Table 2 below.
The solid content, volume average particle size, and viscosity of the obtained emulsion are shown in Table 3 below.

[Comparative Example 3]
An emulsion was produced by performing the same treatment as in Example 1 except that the raw materials were formulated as shown in Table 2 below.
The solid content, volume average particle size, and viscosity of the obtained emulsion are shown in Table 3 below.

[Calculation of silanol group-containing segment amount]
<Amount of Silanol Group-Containing Segment in Comparative Example 3>
^{FIG. 1 shows a 29} Si solid-state NMR spectrum measured using the emulsion produced in Comparative Example 3. The numbers shown in the spectral diagram of FIG. 1 indicate the integrated value (molar ratio) of the signal derived from the structure containing each silanol group shown in Table 1. Table 4 below shows the structure containing each silanol group constituting the emulsion in Comparative Example 3, the signal integral value of each structure, and the silanol group-containing segment amount obtained from the signal integral value of each structure. rice field. The silanol group-containing segment amount (mol%) was calculated by the formula (2-1).
<Amount of silanol group-containing segments of Examples 1 to 5 and Comparative Examples 1 and 2>
In Examples 1 to 5 and Comparative Examples 1 and 2, the ²⁹ Si solid-state NMR spectrum was measured in the same manner as in Comparative Example 3, and the amount of silanol group-containing segments was determined. Table 4 below shows the amount of each segment of Examples 1 to 5 and Comparative Examples 1 and 2 and the amount of silanol group-containing segment.

[Evaluation of stability over time in Examples 1 to 5 and Comparative Examples 1 to 3]
The obtained emulsion was stored in a constant temperature bath at 60 ° C. for 4 weeks, and the rate of increase in volume average particle size and the rate of increase / decrease in viscosity before and after the storage test were carried out according to <(7) Evaluation of stability over time>.
It was found that the emulsions of Examples 1 to 5 gave less change in particle size and less increase / decrease in viscosity before and after the storage test than the emulsions of Comparative Examples 1 to 3.

[Evaluation results of coating film performance before and after the storage test of Examples 1 to 5 and Comparative Examples 1 to 3]
Table 4 below shows the haze values in the water absorption whitening test of the coating film prepared before the storage test of each emulsion of Examples 1 to 5 and Comparative Examples 1 to 3 and after storing each emulsion in a constant temperature bath at 60 ° C. for 2 weeks. Indicated.
It was found that the haze values of Comparative Examples 1 to 3 after the storage test were lower than those of Examples 1 to 5. It is considered that this is because in Comparative Examples 1 to 3, the particle size distribution is widened due to the aggregation of some particles after the storage test, so that the close-packed structure at the time of forming the coating film is impaired.

Claims (6)

An emulsion containing a silicone component after hydrolysis and condensation of the component (A).
The amount of silanol group-containing segments in the silicone component after hydrolysis and condensation of the component (A) defined by the following formula (2) is less than 1 mol% with respect to the total amount of segments derived from the silicone structure of the component (A). There is an emulsion.
Component (A): Organic silane compound represented by the following formula (1)

(In equation (1),
R ¹ is a phenyl group or a cyclohexyl group and
R ² is a hydrogen atom or an aliphatic hydrocarbon group having 1 to 8 carbon atoms.
R ³ is independently an alkoxy group, an acetoxy group, or a hydroxyl group having 1 to 3 carbon atoms.
(N, m) is at least one selected from the group of combinations consisting of (0,1), (0,2), (1,0) and (2,0). );

(In equation (2),
In equation (1), D is the ^{amount of signal identified in the 29 Si solid-state NMR spectrum when R 3} is 4- (n + m) is 2, and Σ is the integral value thereof.
^{T is the amount of signal identified in the 29 Si solid-state NMR spectrum when R 3} is 4- (n + m) in equation (1), and Σ is the integral value thereof.
The numbers in the subscripts of D and T represent the respective Si—O coupling steps. ) A copolymer containing the component (A), the component (B), and the component (C) as a monomer component, and water.
The emulsion according to claim 1.
Component (A): Organic silane compound represented by the formula (1) Component (B): Ethylene unsaturated monomer of the following (b1) and (b2) (however, an organic silane compound having an ethylenically unsaturated group) except for.),
(B1) Unsaturated carboxylic acid ester monomer,
(B2) Unsaturated carboxylic acid monomer,
Component (C): Organic silane compound having an ethylenically unsaturated group The content ratio of the component (A) to the total of the component (A), the component (B), and the component (C) is 30% by mass or less.
The emulsion according to claim 2. The component (C) is γ-acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-methacryloxypropylmethyldimethoxysilane. One or more species selected from the group consisting of
The emulsion according to any one of claims 1 to 3. Component (E): Further containing a catalyst,
The emulsion according to any one of claims 1 to 4. The method for producing an emulsion according to any one of claims 1 to 5.
A step of performing a hydrolysis condensation reaction of a component (A), an addition polymerization reaction of a component (B), and a hydrolysis condensation reaction and an addition polymerization reaction of a component (C) in the presence of the component (E) is included. Production method.
Component (A): Organic silane compound represented by the formula (1) Component (B): Ethylene unsaturated monomer of the following (b1) and (b2) (however, an organic silane compound having an ethylenically unsaturated group) except for.),
(B1) Unsaturated carboxylic acid ester monomer,
(B2) Unsaturated carboxylic acid monomer,
Component (C): Organic silane compound having an ethylenically unsaturated group (E) Component: Catalyst

Images