JP7390827B2 - Polysiloxane resin and its use - Google Patents

Description

The present invention relates to polysiloxane resins and their use.

Paints containing polysiloxane are known as paints that provide coating films that exhibit high durability. For example, Patent Document 1 describes a curable resin composition containing a resin obtained by condensing a polymer having a hydrolyzable silyl group and a polysiloxane having a hydroxyl group bonded to a silicon atom, and a curing catalyst. An object (paint) is disclosed.

Japanese Patent Application Publication No. 9-176489

Patent Document 1 mentioned above is a paint using an organic solvent. However, in recent years, even in the field of paints, attempts have been made to switch from using organic solvents to water-soluble or water-dispersible resins from the viewpoint of pollution control and resource conservation.

On the other hand, as water-based paints, paints containing acrylic silicone resins are known. Paint films obtained from paints containing acrylic silicone resins have excellent weather resistance, but recent market needs call for the development of paints with even higher weather resistance.

The present invention was made in view of the above-mentioned problems, and its purpose is to provide a new polysiloxane resin that can be used as a water-based paint and provides a coating film with excellent weather resistance, and technology for utilizing the same. Our goal is to provide the following.

As a result of intensive studies to solve the above problems, the present inventors have discovered that a water-soluble polysiloxane resin can be obtained by adding a salt structure consisting of an acid and a base to a polysiloxane resin, and that The inventors discovered for the first time that a coating film with excellent weather resistance can be obtained when a polysiloxane resin is used as a water-based coating material, leading to the completion of the present invention.

Therefore, one embodiment of the present invention includes the following configuration.
<1> Having a polymer containing a structural unit derived from a monomer having a radically polymerizable group as a structural unit,
Furthermore, it has a salt structure consisting of an acid and a base,
Polysiloxane resin.
<2> A structural unit (a) derived from an organopolysiloxane compound (A) having a radically polymerizable unsaturated group,
A structural unit (b) derived from a monomer (B) having a salt structure consisting of an acid and a base and having a radically polymerizable group;
Optionally, a structural unit (c) derived from a monomer (C) having a radically polymerizable group other than the above (A) and (B),
The polysiloxane resin according to <1>, comprising:
<3> The polysiloxane resin according to <2>, wherein the structural unit (b) is 2% by weight or more based on the total amount of (a) to (c).
<4> Contains the polysiloxane resin according to any one of <1> to <3>,
An aqueous solution in which the polysiloxane resin is uniformly dispersed or soluble in water.
<5> A resin composition comprising the polysiloxane resin according to any one of <1> to <3>.
<6> The resin composition according to <5>, wherein water is contained in an amount of 30% by weight or more and a non-aqueous solvent is contained in a proportion of 10% by weight or less with respect to the polysiloxane resin.
<7> An organopolysiloxane compound (A) having a radically polymerizable unsaturated group,
A monomer (B) having a salt structure consisting of an acid and a base and having a radically polymerizable group;
Optionally, a monomer (C) having a radically polymerizable group other than the above (A) and (B),
A method for producing a polysiloxane resin, comprising the step of copolymerizing.
<8> The method for producing a polysiloxane resin according to <7>, wherein the copolymerization is performed in a nonaqueous solvent.
<9> The method for producing a polysiloxane resin according to <7> or <8>, further comprising a step of replacing the nonaqueous solvent with an aqueous solvent after the copolymerization step.
<10> Further, a step of condensing an alkoxysilane compound and an alkoxysilane compound having a radically polymerizable unsaturated group to obtain the organopolysiloxane compound (A) having the radically polymerizable unsaturated group. , the method for producing a polysiloxane resin according to any one of <7> to <9>.

Further, another embodiment of the present invention includes the following configuration.
<11> The number of moles of water used in the condensation is 1.0 to 4.0 times the total number of moles of the alkoxysilane compound and the alkoxysilane compound having a radically polymerizable unsaturated group, <10>, the method for producing a polysiloxane resin.
<12> The method for producing a polysiloxane resin according to <10> or <11>, wherein the alkoxysilane compound having a radically polymerizable unsaturated group is 2 to 10% by weight based on the total alkoxysilane compound. .
<13> The polysiloxane resin according to any one of <7> to <12>, wherein the monomer (B) is 2% by weight or more based on the total amount of the (A) to (C). manufacturing method.
<14> The polysiloxane system according to any one of <7> to <13>, wherein the organopolysiloxane compound (A) is 30% by weight or more based on the total amount of (A) to (C). Method of manufacturing resin.
<15> Having a polymer containing a structural unit derived from a monomer having a radically polymerizable group as a structural unit,
Furthermore, it has a salt structure consisting of an acid and a base,
uniformly dispersed or soluble in water;
Polysiloxane resin.

According to one aspect of the present invention, it is possible to provide a novel polysiloxane resin that can be used as a water-based paint and provides a coating film with excellent weather resistance, and a technique for utilizing the same.

One embodiment of the present invention will be described in detail below. In this specification, unless otherwise specified, the numerical range "A to B" means "A or more and B or less". Additionally, all documents mentioned herein are incorporated by reference herein.

[1. Summary of the invention]
Conventionally, polysiloxane resins are insoluble or do not disperse uniformly in water, so it has been difficult to use them as compositions for water-based coatings. On the other hand, acrylic silicone resins that can be used as water-based paints have been found to have limited weather resistance. The reason for this is thought to be that the main chain of acrylic silicone resin is composed of acrylic, which has a relatively low bonding energy, and siloxane, which has a high bonding energy, is used as a side chain. .

Therefore, the present inventor conducted extensive studies in order to develop a polysiloxane resin that can be used for water-based paints and can achieve both higher weather resistance and environmental performance. As a result, by introducing a salt structure consisting of an acid and a base into a polysiloxane resin as a side chain, they succeeded in developing a polysiloxane resin that can be uniformly dispersed or soluble in an aqueous solvent. Furthermore, when this polysiloxane resin is used as a water-based paint, the resulting coating film exhibits higher weather resistance in weather resistance tests than conventional acrylic silicone resins.

[2. Polysiloxane resin〕
The polysiloxane resin according to one embodiment of the present invention (hereinafter referred to as "the present polysiloxane resin") is a polymer containing, as a constitutional unit, a constitutional unit derived from a monomer having a radically polymerizable group. It is characterized by having a salt structure consisting of an acid and a base.

This polysiloxane-based resin has the above-mentioned characteristic structure, so it can be used as a water-based paint, and when this polysiloxane-based resin is used as a water-based paint, the resulting coating film is weather resistant. Excellent in sex.

Moreover, since the present polysiloxane resin has the above-mentioned performance, it can also be expressed as follows.

It has a polymer containing a structural unit derived from a monomer having a radically polymerizable group as a structural unit, further has a salt structure consisting of an acid and a base, and is uniformly dispersed or soluble in water. Polysiloxane resin.

As used herein, "polysiloxane resin" means a resin containing a polysiloxane structure as a main component. The polysiloxane resin is not particularly limited as long as it satisfies the above definition, but for example, it can be hydrolyzed and condensed with a single compound represented by the following general formula (1) or a plurality of compounds represented by the following general formula (1). Examples include polysiloxane resins obtained by cohydrolytic condensation with a compound.

R ^a _n Si (OR ^b ) _4-n (1)
(In the formula, R ^a is each independently an alkyl group, a cycloalkyl group, an alkenyl group, a halogen-substituted hydrocarbon group, an epoxy group-containing hydrocarbon group, a (meth)acryloyl group-containing hydrocarbon group, or an amino group-containing hydrocarbon group) It is a hydrogen group, each R ^b is independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and n is an integer of 0 to 3.)
In one embodiment of the present invention, in the above general formula (1), R ^a is preferably an alkyl group from the viewpoint of storage stability, and from the viewpoint of initial gloss value, n=1 -2 is preferred, from the viewpoint of ease of condensation, R ^b is preferably a methyl group, and from the viewpoint of weather resistance, preferably n = 1.

As used herein, the term "salt structure" refers to the structure of a neutral salt obtained by neutralizing an acid and a base. Here, the acid used for neutralization may be a strong acid or a weak acid. Further, the base used for neutralization may be a strong base or a weak base.

In one embodiment of the present invention, the salt structure is, for example, a structure of a neutral salt of a strong acid and a strong base, a structure of a neutral salt of a strong acid and a weak base, a structure of a neutral salt of a weak acid and a strong base, Alternatively, it may have the structure of a neutral salt of a weak acid and a weak base. More specific salt structures include, for example, sodium sulfonate, potassium sulfonate, calcium sulfonate, sodium nitrate, potassium nitrate, calcium nitrate (structure of a neutral salt of a strong acid and a strong base), ammonium sulfonate, and ammonium nitrate. etc. (Structure of a neutral salt of a strong acid and a weak base), Sodium acetate, Potassium acetate, Calcium acetate, Sodium phosphate, Potassium phosphate, Calcium phosphate, etc. (Structure of a neutral salt of a weak acid and a strong base), Ammonium acetate , ammonium phosphate (a structure of a neutral salt of a weak acid and a weak base), and the like. In one embodiment of the invention, the salt structure is preferably sodium sulfonate.

In this specification, "uniformly dispersed or soluble in water" means "precipitate" when a solution containing a polysiloxane resin is evaluated by the method described in (Aqueous solution appearance) in the Examples below. means something that does not occur. In other words, "uniformly dispersed or soluble in water" means that when a solution containing a polysiloxane resin is evaluated by the method described in (Aqueous solution appearance) in the examples below, It means that the solution containing is evaluated as "colorless and transparent", "blue-white and transparent", or "white dispersion".

In one embodiment of the present invention, the polysiloxane resin has a structural unit (a) derived from an organopolysiloxane compound (A) having a radically polymerizable unsaturated group, and a salt structure consisting of an acid and a base. , and a structural unit (b) derived from the monomer (B) having a radically polymerizable group, and optionally a monomer (C) having a radically polymerizable group other than the above (A) and (B). It is preferable to include a structural unit (c) derived from.

In addition, hereinafter, "the structural unit (a) derived from the organopolysiloxane compound (A) having a radically polymerizable unsaturated group" will be simply referred to as "the structural unit (a)", and will be referred to as "the salt consisting of an acid and a base". "Structural unit (b) derived from the monomer (B) having a structure and a radically polymerizable group" is simply referred to as "Structural unit (b)," and "Structural unit (b) other than the above (A) and (B) The "structural unit (c) derived from the monomer (C) having a radically polymerizable group" is simply referred to as "the structural unit (c)." In addition, hereinafter, "organopolysiloxane compound (A) having a radically polymerizable unsaturated group" will be simply referred to as "organopolysiloxane compound (A)", and "organopolysiloxane compound (A) having a salt structure consisting of an acid and a base, and The monomer (B) having a radically polymerizable group is simply referred to as the monomer (B), and the monomer (C )" is simply referred to as "monomer (C)."

(Constituent unit (a))
The structural unit (a) consists of a structural unit derived from an organopolysiloxane compound (A) having a radically polymerizable unsaturated group. The organopolysiloxane compound (A) from which the structural unit (a) is derived is obtained by condensing an alkoxysilane compound and an alkoxysilane compound having a radically polymerizable unsaturated group. Hereinafter, the alkoxysilane compound and the alkoxysilane compound having a radically polymerizable unsaturated group will be explained.

The alkoxysilane compound has the following general formula (I):
R ¹ _a -(Si(OR ² ) _4-a ) (I)
(In the formula, R ¹ is an alkyl group having 1 to 10 carbon atoms or an unsubstituted or substituted aryl group, R ² is each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and a is 0 It is an integer between ~3.)
It is a compound having a hydrolyzable silyl group represented by:

The alkoxysilane compound having a radically polymerizable unsaturated group has the following general formula (II):
R ³ _b -(Si(OR ⁴ ) _4-b ) (II)
(In the formula, R ³ has a substituted alkyl group having 1 to 10 carbon atoms, an alkenyl group, or a polymerizable unsaturated group having a polymerizable unsaturated group, and may optionally have other substituents. It is an aryl group, each R ⁴ is independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and b is an integer of 1 to 3.)
It is a compound having a hydrolyzable silyl group represented by:

Specific examples of the alkyl group for R ¹ in general formula (I) include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, amyl group, isoamyl group, hexyl group, cyclohexyl group, cyclohexyl group. Examples include methyl group, cyclohexylethyl group, heptyl group, isoheptyl group, n-octyl group, isooctyl group, and 2-ethylhexyl group.

R ² in general formula (I) is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, octyl group, nonyl group, decyl group. Examples include groups.

Specific compounds represented by general formula (I) include tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltriisopropoxysilane, ethyltrimethoxysilane, Ethyltriethoxysilane, ethyltriisopropoxysilane, propyltrimethoxysilane, propyltriethoxysilane, propyltriisopropoxysilane, butyltrimethoxysilane, butyltriethoxysilane, butyltriisopropoxysilane, hexyltrimethoxysilane, hexyltrimethoxysilane Ethoxysilane, hexyltriisopropoxysilane, octyltrimethoxysilane, octyltriethoxysilane, octyltriisopropoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriisopropoxysilane, dimethyldimethoxysilane, diphenyldimethoxysilane, trimethyl Examples include monomethoxysilane and triphenylmonomethoxysilane.

In particular, preferred compounds from the viewpoint of availability include methyltrimethoxysilane, phenyltrimethoxysilane, and dimethyldimethoxysilane.

From the viewpoint of easy condensation of an alkoxysilane compound and an alkoxysilane compound having a radically polymerizable unsaturated group, the number of carbon atoms in the alkyl group of R ² in general formula (I) is preferably 1 to 3, most preferably 1. It is.

R ³ in the general formula (II) is a substituted alkyl group having 1 to 10 carbon atoms having a radically polymerizable unsaturated group, an alkenyl group, or an unsubstituted or substituted aryl group having a radically polymerizable unsaturated group. Examples of the radically polymerizable unsaturated group include a (meth)acryloyl group.

Examples of the silane compound in which R ³ is an alkyl group having a radically polymerizable unsaturated group include (meth)acryloxymethyltrimethoxysilane, (meth)acryloxymethylmethyldimethoxysilane, and (meth)acryloxymethyldimethylmethoxy. Silane, (meth)acryloxymethyltriethoxysilane, (meth)acryloxymethylmethyldiethoxysilane, (meth)acryloxymethyldimethylethoxysilane, 2-(meth)acryloxyethyltrimethoxysilane, 2-(meth) Acryloxyethylmethyldimethoxysilane, 2-(meth)acryloxyethyldimethylmethoxysilane, 2-(meth)acryloxyethyltriethoxysilane, 2-(meth)acryloxyethylmethyldiethoxysilane, 2-(meth)acrylic Roxyethyldimethylethoxysilane, γ-(meth)acryloxypropyltrimethoxysilane, γ-(meth)acryloxypropylmethyldimethoxysilane, γ-(meth)acryloxypropyldimethylmethoxysilane, γ-(meth)acryloxypropyl Triethoxysilane, γ-(meth)acryloxypropylmethyldiethoxysilane, γ-(meth)acryloxypropyldimethylethoxysilane, 4-(meth)acryloxybutyltrimethoxysilane, 4-(meth)acryloxybutylmethyl Dimethoxysilane, 4-(meth)acryloxybutyldimethylmethoxysilane, 4-(meth)acryloxybutyltriethoxysilane, 4-(meth)acryloxybutylmethyldiethoxysilane, 4-(meth)acryloxybutyldimethylethoxy Silane, 5-(meth)acryloxypentyltrimethoxysilane, 5-(meth)acryloxypentylmethyldimethoxysilane, 5-(meth)acryloxypentyldimethylmethoxysilane, 5-(meth)acryloxypentyltriethoxysilane, 5-(meth)acryloxypentylmethyldiethoxysilane, 5-(meth)acryloxypentyldimethylethoxysilane, 6-(meth)acryloxyhexyltrimethoxysilane, 6-(meth)acryloxyhexylmethyldimethoxysilane, 6 -(meth)acryloxyhexyldimethylmethoxysilane, 6-(meth)acryloxyhexyltriethoxysilane, 6-(meth)acryloxyhexylmethyldiethoxysilane, 6-(meth)acryloxyhexyldimethylethoxysilane, etc. It will be done.

Examples of the silane compound in which R ³ is an alkenyl group include vinyltrimethoxysilane, vinylmethyldimethoxysilane, vinyldimethylmethoxysilane, vinyltriethoxysilane, vinylmethyldiethoxysilane, vinyldimethylethoxysilane, and the like.

Examples of the silane compound in which R ³ is an aryl group having a polymerizable unsaturated group and optionally having other substituents include p-styryltrimethoxysilane, p-styrylmethyldimethoxysilane, Examples include p-styryldimethylmethoxysilane, p-styryltriethoxysilane, p-styrylmethyldiethoxysilane, and p-styryldimethylethoxysilane.

Among these, from the viewpoint of thermal radical polymerization reactivity, R ³ is preferably a (meth)acryloyl group-substituted alkyl group.

R ⁴ in general formula (II) is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, octyl group, nonyl group, decyl group, etc. Examples include groups.

From the viewpoint of easy condensation of an alkoxysilane compound and an alkoxysilane compound having a radically polymerizable unsaturated group, the number of carbon atoms in the alkyl group of R ⁴ in general formula (II) is preferably 1 to 3, most preferably 1. It is.

The number of moles of water added to condense the alkoxysilane compound and the alkoxysilane compound having a radically polymerizable unsaturated group is the total number of moles of the alkoxysilane compound and the alkoxysilane compound having a radically polymerizable unsaturated group. For example, it may be 1.0 times as large as that of the target. When the number of moles of water is less than 1.0 times the total number of moles of the alkoxysilane compound and the alkoxysilane compound having a radically polymerizable unsaturated group, the alkoxysilane compound and the radically polymerizable unsaturated group The condensation reaction with an alkoxysilane compound having a saturated group is not completed, and a portion remains without increasing the molecular weight. Therefore, in the vacuum distillation step which is a step of removing alcohol generated during the reaction process, the alkoxysilane compound and the alkoxysilane compound having a radically polymerizable unsaturated group are volatilized, resulting in loss. Furthermore, silanol groups produced by hydrolyzing alkoxysilyl groups undergo dehydration condensation with silanol groups and dealcoholization condensation with alkoxysilyl groups, which causes a decrease in the storage stability of the organopolysiloxane compound. On the other hand, since silanol groups are solvated with hydrophilic solvents such as alcohol, a certain amount or more of silanol groups also has the effect of improving the storage stability of the organopolysiloxane compound. Furthermore, since the organopolysiloxane compound tends to gel when concentrated in the vacuum distillation process, there is a possibility that it cannot be concentrated to a high concentration. From this viewpoint, the number of moles of water to be added is more preferably 1.5 times or more the total number of moles of the alkoxysilane compound and the alkoxysilane compound having a radically polymerizable unsaturated group.

There is no particular restriction on the number of moles of water to be added, but as the solid content concentration decreases during production, the production cost increases. It is preferable to suppress the total number of moles with the compound to 4.0 times or less. Based on these points of view, the number of moles of water to be added is preferably 1.0 to 4.0 times the total number of moles of the alkoxysilane compound and the alkoxysilane compound having a radically polymerizable unsaturated group; It is more preferably .5 to 3.0 times, and particularly preferably 2.0 to 2.5 times.

When condensing an alkoxysilane compound and an alkoxysilane compound having a radically polymerizable unsaturated group, the amount of the alkoxysilane compound having a radically polymerizable unsaturated group is determined by the amount of the alkoxysilane compound having a radically polymerizable unsaturated group. For example, the amount is 2 to 10% by weight, preferably 3 to 8% by weight, and more preferably 4 to 6% by weight based on the total weight of the alkoxysilane compound (based on all the alkoxysilane compounds). be. When the amount of the alkoxysilane compound having a radically polymerizable unsaturated group is within the above range, the organopolysiloxane compound can be uniformly dispersed or soluble in water through sufficient graft polymerization with the structural unit (b), and the organopolysiloxane compound (A) has the effect of preventing gelation due to self-polymerization.

When condensing an alkoxysilane compound and an alkoxysilane compound having a radically polymerizable unsaturated group, it is preferable to add a catalyst for the purpose of improving the reaction rate. As a catalyst for hydrolysis and condensation of alkoxysilyl groups, acidic catalysts, basic catalysts, etc. can be used.

As the acidic catalyst, organic acids are preferred from the viewpoint of compatibility with the organopolysiloxane compound and the diluting solvent, and phosphoric acid esters and carboxylic acids can be suitably used. Specific examples of organic acids include ethyl acid phosphate, butyl acid phosphate, dibutyl pyrophosphate, butoxyethyl acid phosphate, 2-ethylhexyl acid phosphate, isotridecyl acid phosphate, dibutyl phosphate, bis(2-ethylhexyl) phosphate, Examples include formic acid, acetic acid, butyric acid, isobutyric acid, and the like. Moreover, as the basic catalyst, an organic basic catalyst is preferable from the viewpoint of compatibility with the organopolysiloxane compound and the diluting solvent, and an amine compound can be suitably used. Specific examples of the organic base include triethylamine, diazabicycloundecene, 1,4-diazabicyclo[2.2.2]octane, and the like. The amount of the catalyst added is preferably 0.1 ppm to 50000 ppm, more preferably 1 ppm to 10000 ppm, particularly preferably 5 ppm to 1000 ppm, and 10 ppm to 500 ppm based on the alkoxysilane compound and the alkoxysilane compound having a radically polymerizable unsaturated group. Most preferred. When the amount of catalyst added is less than 0.1 ppm, it hardly acts as a catalyst. Although a large amount of catalyst can shorten the reaction time, it is often difficult to separate and remove it from the organopolysiloxane compound after the reaction is completed. The remaining catalyst may reduce the storage stability of the organopolysiloxane compound (A) and the present polysiloxane resin, so there is a balance with production time, but from a practical standpoint, the smaller the amount, the better.

Further, a diluting solvent may be used during production. Since the alkoxysilane compound and the alkoxysilane compound having a radically polymerizable unsaturated group are hydrophobic and water is used during the reaction, the diluting solvent is preferably water-soluble. There is no limit to the amount of diluting solvent used, but if it increases, the concentration of the organopolysiloxane compound (A) obtained will decrease, which is not preferable from the viewpoint of production costs. When the number of carbon atoms in the organic group of organotrialkoxysilane is 3 or more, the resulting organopolysiloxane compound (A) is often incompatible with the alcohol (methanol, ethanol, propanol) generated during production. It is preferable to carry out the reaction in a compatible system using a diluting solvent. From this viewpoint, a hydrophilic solvent having 4 or more carbon atoms is suitable as the diluting solvent. When the number of carbon atoms is 3 or less, the solubility in the organopolysiloxane compound (A) may become insufficient as described above. Specific examples of diluent solvents include diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, polyethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, diethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, and diethylene glycol monobutyl ether. , triethylene glycol monobutyl ether, ethylene glycol monoisobutyl ether, diethylene glycol monoisobutyl ether, propylene glycol monomethyl ether, propylene glycol dimethyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether , ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, ethylene glycol diethyl ether, and the like. Among these, in consideration of the need to volatilize the polysiloxane resin after production or during coating film formation, diluting solvents with a boiling point of 150°C or lower at atmospheric pressure are preferable, such as ethylene glycol monoethyl ether, ethylene glycol Particularly preferred are monoisopropyl ether, propylene glycol monomethyl ether, propylene glycol monopropyl ether, propylene glycol monoethyl ether, and propylene glycol dimethyl ether.

In one embodiment of the present invention, the content of the structural unit (a) is, for example, 30% by weight or more, preferably 35% by weight or more, based on the total amount of (a) to (c) above. , more preferably 40% by weight or more, particularly preferably 43% by weight or more, particularly preferably 45% by weight or more. When the content of the structural unit (a) is within the above range, high weather resistance can be achieved when used as a paint. Further, the upper limit of the content of the structural unit (a) is not particularly limited as long as the effects of the present invention are achieved, but is, for example, 95% by weight or less, preferably 90% by weight or less, and more preferably 85% by weight or less. % by weight or less.

(Constituent unit (b))
The structural unit (b) has a salt structure consisting of an acid and a base, and is composed of a structural unit derived from the monomer (B) having a radically polymerizable group. The monomer (B) from which the structural unit (b) is derived is bonded by radical polymerization with the organopolysiloxane compound (A) and/or the monomer (C) to form the structural unit (a) and/or the structural unit. Combine with (c).

Since the monomer (B) from which the structural unit (b) is derived has a salt structure consisting of an acid and a base, the polysiloxane resin can be uniformly dispersed or soluble in water.

The radically polymerizable unsaturated group in the monomer (B) is not particularly limited as long as it can contribute to radical polymerization with the organopolysiloxane compound (A) and the monomer (C). Examples of the radically polymerizable unsaturated group in the monomer (B) include a (meth)acryloyl group, a (meth)acrylamide group, and a vinyl group.

In one embodiment of the present invention, the radically polymerizable unsaturated group in the monomer (B) is preferably a radically polymerizable unsaturated group of at least one of a (meth)acryloyl group and a (meth)acrylamide group. It can be.

The monomer (B) from which the structural unit (b) is derived is not particularly limited as long as it has a salt structure consisting of an acid and a base and a radically polymerizable group, but for example, sulfoethyl Sodium methacrylate, sodium acrylamide-t-butylsulfonate, sodium 2-(methacryloyloxy)ethanesulfonate, sodium 2-(methacryloyloxy)polyalkylene oxide sulfonate, sodium acrylamide-t-butylsulfonate, 2-(methacryloyloxy) Potassium ethanesulfonate, 2-(methacryloyloxy)potassium polyalkylene oxide sulfonate, potassium acrylamide-t-butylsulfonate, calcium 2-(methacryloyloxy)ethanesulfonate, calcium 2-(methacryloyloxy)polyalkylene oxide sulfonate, Calcium acrylamide-t-butylsulfonate, ammonium sulfoethyl methacrylate, ammonium acrylamide-t-butylsulfonate, ammonium 2-(methacryloyloxy)ethanesulfonate, ammonium 2-(methacryloyloxy)polyalkylene oxide sulfonate, t-butyl acrylamide Examples include ammonium sulfonate, sodium acrylate, potassium acrylate, calcium acrylate, ammonium acrylate, sodium methacrylate, potassium methacrylate, calcium methacrylate, and ammonium methacrylate.

Furthermore, the monomer (B) from which the structural unit (b) is derived can be obtained as a commercially available product. Such commercial products include, for example, "Antox MS-2N-D" manufactured by Nippon Nyukazai Co., Ltd., "ATBS-Na" manufactured by Toagosei Co., Ltd., and "Eleminol RS-3000" manufactured by Sanyo Chemical Industries, Ltd. ”, “sodium acrylate” and “potassium acrylate” manufactured by Asada Chemical Industry Co., Ltd.

In one embodiment of the present invention, the content of the structural unit (b) is, for example, 2% by weight or more, preferably 2.3% by weight or more, based on the total amount of (a) to (c) above. It is more preferably 2.5% by weight or more, particularly preferably 2.7% by weight or more, particularly preferably 2.9% by weight or more. When the content of the structural unit (b) is within the above range, it has the effect of being uniformly dispersed or solubilized in water. Further, the upper limit of the content of the structural unit (b) is not particularly limited as long as the effects of the present invention are achieved, but is, for example, 50% by weight or less, preferably 30% by weight or less, and more preferably 20% by weight or less. % by weight or less.

(Constituent unit (c))
The structural unit (c) consists of a structural unit derived from a monomer (C) having a radically polymerizable unsaturated group other than the above-mentioned (A) and (B). The monomer (C) from which the structural unit (c) is derived is bonded by radical polymerization with the organopolysiloxane compound (A) and/or the monomer (B) to form the structural unit (a) and/or the structural unit. (b).

The monomer (C) from which the structural unit (c) is derived is not particularly limited as long as it is a monomer having a radically polymerizable unsaturated group other than the above (A) and (B), but for example, the following: Examples include (meth)acrylic acid alkyl esters as shown in (meth)acrylic acid alkyl esters, and monomers other than (meth)acrylic acid alkyl esters.

<(meth)acrylic acid alkyl ester>
In one embodiment of the present invention, the (meth)acrylic acid alkyl ester is a (meth)acrylic ester having an alkyl group having 1 to 18 carbon atoms, and does not contain a functional group such as a hydroxyl group or an epoxy group. ) may be an alkyl monomer. In one embodiment of the present invention, the alkyl group in the (meth)acrylic acid alkyl ester may be linear or branched, or may be a cyclic cycloalkyl group. Specific examples include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, iso-butyl (meth)acrylate, tert-butyl (meth)acrylate, benzyl (meth)acrylate, Examples include cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isodecyl (meth)methacrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, stearyl (meth)acrylate, isobonyl (meth)acrylate, and the like.

<Monomer other than (meth)acrylic acid alkyl ester>
Monomers other than (meth)acrylic acid alkyl esters include, for example, nitrile group-containing radically polymerizable monomers such as (meth)acrylonitrile; epoxy group-containing radically polymerizable monomers such as glycidyl (meth)acrylate; 2-hydroxypropyl (meth)acrylate; 2-hydroxypropyl (meth)acrylate; has hydrophilic properties such as sodium 2-sulfoethyl methacrylate, ammonium 2-sulfoethyl methacrylate, and radically polymerizable monomers having polyoxyalkylene chains. Radically polymerizable monomer; Monomer having two or more polymerizable unsaturated bonds such as polyethylene glycol di(meth)acrylate, ethylene glycol di(meth)acrylate, allyl(meth)acrylate; Trifluoro(meth)acrylate Fluorine-containing radically polymerizable monomers such as acrylate, pentafluoro(meth)acrylate, perfluorocyclohexyl(meth)acrylate, 2,2,3,3-tetrafluoropropyl methacrylate, β-(perfluorooctyl)ethyl(meth)acrylate, etc. mer; etc.

Further, the radically polymerizable monomer having a polyoxyalkylene chain is not particularly limited, but acrylic esters or methacrylic esters having a polyoxyalkylene chain are preferable. Specific examples include Blenmar PE-90, PE-200, PE-350, AE-90, AE-200, AE-350, PP-500, PP-800, PP-1000 manufactured by NOF Corporation. , AP-400, AP-550, AP-800, 700PEP-350B, 10PEP-550B, 55PET-400, 30PET-800, 55PET-800, 30PPT-800, 50PPT-800, 70PPT-800, PME-100, PME -200, PME-400, PME-1000, PME-4000, AME-400, 50POEP-800B, 50AOEP-800B, AEP, AET, APT, PLE, ALE, PSE, ASE, PKE, AKE, PNE, ANE, PNP , ANP, PNEP-600, Kyoeisha Chemical Co., Ltd. Light Ester 130MA, 041MA, MTG, Light Acrylate EC-A, MTG-A, 130A, DPM-A, P-200A, NP-4EA, NP-8EA, EHDG -A, MA-30, MA-50, MA-100, MA-150, RMA-1120, RMA-564, RMA-568, RMA-506, MPG130-MA, Antox MS-60, manufactured by Nippon Nyukazai Co., Ltd. MPG-130MA, RMA-150M, RMA-300M, RMA-450M, RA-1020, RA-1120, RA-1820, NK-ESTER M-20G, M-40G, M-90G manufactured by Shin Nakamura Chemical Industry Co., Ltd. , M-230G, AMP-10G, AMP-20G, AMP-60G, AM-90G, LA, etc.

In one embodiment of the present invention, the content of the structural unit (c) is, for example, 6% by weight or more, preferably 7% by weight or more, based on the total amount of (a) to (c) above. , more preferably 8% by weight or more. When the content of the structural unit (c) is within the above range, it has the effect of imparting elasticity to the coating film. Further, the upper limit of the content of the structural unit (c) is not particularly limited as long as the effects of the present invention are achieved, but is, for example, 50% by weight or less, preferably 48% by weight or less, and more preferably 47% by weight or less. % by weight or less.

Further, the weight average molecular weight of the present polysiloxane resin is, for example, 1,000 to 1,000,000, preferably 3,000 to 100,000, and more preferably 4,000 to 50,000. If the weight average molecular weight of the present polysiloxane resin is within the above range, it has the advantage of achieving both weather resistance and viscosity.

[3. Resin composition]
The resin composition according to one embodiment of the present invention (hereinafter referred to as "the present resin composition") is described in [2. Polysiloxane Resin] is a resin composition containing the polysiloxane resin described in [Polysiloxane Resin]. This resin composition can be used as a water-based paint, and since it contains a polysiloxane resin that gives the resulting coating film excellent weather resistance when used as a water-based paint, it is particularly useful for water-based paints. It is useful in

The present resin composition is prepared from the above [2. For example, the proportion of water is 30% by weight or more and the non-aqueous solvent is 10% by weight or less, preferably the proportion of water is 35% by weight or more and the non-aqueous solvent is The aqueous solvent may be contained in a proportion of 5% by weight or less, and more preferably, the proportion of water may be 37% by weight or more and the non-aqueous solvent may be contained in a proportion of 3% by weight or less.

As used herein, "non-aqueous solvent" means all solvents other than water. The "non-aqueous solvent" herein may be a mixed solvent containing water, and includes a solvent containing water in an amount of less than 50% by weight. The non-aqueous solvent is not particularly limited as long as it satisfies the above definition, but includes, for example, hydrocarbons such as toluene, xylene, n-hexane, and cyclohexane; acetate esters such as ethyl acetate and butyl acetate; ethyl cellosolve; Cellosolves such as butyl cellosolub; Ether esters such as cellosolve acetate; Ketones such as methyl ethyl ketone, ethyl acetoacetate, acetylacetone, methyl isobutyl ketone, acetone; Alcohols such as methanol, isopropyl alcohol, n-butanol, isobutanol, hexanol, octanol, etc. etc. In one embodiment of the invention, the non-aqueous solvent is preferably an alcohol, more preferably isopropyl alcohol.

Moreover, the present resin composition has [2. In addition to the polysiloxane resin described in [Polysiloxane Resin], a curing catalyst may be included. When coating this resin composition, the crosslinking reaction is promoted by adding a curing catalyst that promotes the hydrolytic condensation reaction of alkoxysilyl groups.

The curing catalyst is not particularly limited, and examples thereof include organometallic compounds, acidic catalysts, basic catalysts, and the like. Among these, from the viewpoint of activity, organic tin compounds, acidic phosphoric esters, and reaction products of acidic phosphoric esters and amine compounds are preferred.

Examples of the organic tin compound include dibutyltin dilaurate, dibutyltin dimalate, dibutyltin dioleyl maleate, dioctyltin dilaurate, dibutyltin diacetate, dibutyltin dimethoxide, dibutyltin thioglycolate, dibutyltin bisisononyl 3-mercaptopropiodine. dibutyltin bisisooctylthioglycolate, dibutyltin bis-2-ethylhexylthioglycolate, dimethyltin bisdodecyl mercaptide, dimethyltin bis(octylthioglycolic acid ester) salt, tin octylate, and the like.

Among them, from the viewpoint of stability in water, dibutyltin thioglycolate, dibutyltin bisisononyl 3-mercaptopropionate, dibutyltin bisisooctylthioglycolate, dibutyltin bis 2-ethylhexyl thioglycolate, dimethyltin bis Mercaptide-based compounds such as dodecyl mercaptide, dibutyltin bisdodecyl mercaptide, and dimethyltin bis(octylthioglycolic acid ester) salt are preferred.

Examples of acidic phosphoric acid ester compounds include propyl acid phosphate, dibutyl phosphate, 2-ethylhexyl acid phosphate, di-2-ethylhexyl phosphate, monoisodecyl acid phosphate, diisodecyl phosphate, lauryl acid phosphate, stearyl acid phosphate, and the like. .

Further, examples of amine compounds that can be reacted with the above acidic phosphoric acid ester compound include triethylamine, n-butylamine, hexylamine, triethanolamine, diazabicycloundecene, and ammonia.

In one embodiment of the present invention, the amount of the curing catalyst added is preferably 0.1 to 10 parts by weight, and 0.5 to 5.0 parts by weight, based on 100 parts by weight of the solid content of the resin composition. More preferably, 1.0 to 3.0 parts by weight is particularly preferred. If it is less than 0.1 part by weight, the curing activity is low, and if it exceeds 10 parts by weight, the pot life of the paint will be shortened, and cracks due to curing shrinkage and embrittlement of the cured product will occur.

The resin composition may contain additives commonly used in the technical field (in particular, the field of coatings) within a range that achieves the effects of the present invention. Examples of such additives include additives, fillers, plasticizers, film-forming aids, wetting/dispersing agents, thickeners, antifoaming agents, preservatives, antioxidants, anti-settling agents, leveling agents, Examples include ultraviolet absorbers, antistatic agents, antifreeze agents, antibacterial agents, antifungal agents, tackifiers, and rust preventives. As the additive, only one type may be included, or two or more types may be included. The amounts of these additives can be appropriately determined by those skilled in the art depending on the purpose of use.

In one embodiment of the present invention, the storage stability of the resin composition is, for example, 2 weeks or more at 50° C. when measured by the method described in the Examples below. When the storage stability is within the above range, the storage stability is excellent.

In one embodiment of the present invention, the gloss value (initial) of the coating film when the present resin composition is used as a water-based paint is, for example, 51 or more when measured by the method described in the Examples below. , preferably 55 or more, more preferably 58 or more, still more preferably 60 or more.

In one embodiment of the present invention, the gloss retention rate of the coating film when the present resin composition is used as a water-based paint is, for example, 65% or more when measured by the method described in the Examples below, Preferably it is 70% or more, more preferably 75% or more, particularly preferably 80% or more. When the gloss retention rate is within the above range, weather resistance is excellent.

Moreover, in one embodiment of the present invention, the above [2. An aqueous solution (hereinafter referred to as "this aqueous solution") containing the polysiloxane resin described in [Polysiloxane Resin] can be provided.

As used herein, the term "aqueous solution" refers to a solution containing 90% by weight or more of water in the total medium. That is, the present aqueous solution only needs to be a solution containing 90% by weight or more of water in all media, and a solution containing a medium other than water (for example, an organic solvent) in an amount of less than 10% may also be used. Included in the concept of this aqueous solution.

This aqueous solution is especially useful in water-based paint applications because it can be used as a water-based paint and contains a polysiloxane-based resin that gives the resulting coating film excellent weather resistance. It is.

[4. Production method〕
A method for producing a water-soluble polysiloxane resin according to an embodiment of the present invention (hereinafter referred to as the "present production method") comprises an organopolysiloxane compound (A) having a radically polymerizable unsaturated group, and an acid A monomer (B) having a salt structure consisting of a base and a radically polymerizable group, and optionally a monomer (C) having a radically polymerizable group other than the above (A) and (B). ) and a step of copolymerizing.

As mentioned above, polysiloxane resins have hitherto been difficult to form into water-based coating compositions because they are insoluble or not uniformly dispersed in water. However, in this production method, by using the above-mentioned organopolysiloxane compound (A), monomer (B), and monomer (C) having a specific structure, it is possible to uniformly disperse or dissolve in an aqueous solvent. A polysiloxane resin is obtained.

Moreover, since the polysiloxane resin obtained by this manufacturing method has the above-mentioned performance, this manufacturing method can also be expressed as follows.

An organopolysiloxane compound (A) having a radically polymerizable unsaturated group, a monomer (B) having a salt structure consisting of an acid and a base and having a radically polymerizable group, and optionally the above (A) and a monomer (C) having a radically polymerizable group other than (B), and a method for producing a polysiloxane resin that is uniformly dispersed or soluble in water.

In one embodiment of the present invention, copolymerization in the present production method may be performed in a non-aqueous solvent. The copolymerization in this production method can be carried out in a non-aqueous solvent as in conventional polysiloxane resin production methods.

As the non-aqueous solvent, for example, the above [3. Resin Composition] may be used.

In one embodiment of the present invention, the production method preferably includes a step of replacing the non-aqueous solvent with an aqueous solvent after the copolymerization step. By including this step, a polysiloxane resin that can be used as a water-based paint and is uniformly dispersed or soluble in water is obtained.

In one embodiment of the present invention, the step of replacing the non-aqueous solvent with an aqueous solvent can be performed, for example, by the steps described in the Examples below.

The polymerization initiator used in the copolymerization step in this production method is not particularly limited, but examples include 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), and 2,2'-azobis(isobutyronitrile). nitrile), 2,2'-azobis(2-methylbutyronitrile), tert-butylperoxypivalate, tert-butylperoxybenzoate, tert-butylperoxy-2-ethylhexanoate, di-tert- Examples include butyl peroxide, cumene hydroperoxide, diisopropyl peroxycarbonate, and the like.

The amount of the polymerization initiator used is, for example, 0.01 to 10 parts, preferably 0.05 to 7 parts by weight, and more preferably 0.1 parts by weight, based on 100 parts by weight of the total monomer. ~5 parts by weight. If the amount of the polymerization initiator used is less than 0.01 part by weight, polymerization may be difficult to proceed, and if it exceeds 10 parts by weight, the molecular weight of the resulting polymer tends to decrease. be.

In one embodiment of the present invention, the amount of monomer (B) is, for example, 2% by weight or more, preferably 2.3% by weight or more, based on the total amount of (A) to (C). It is more preferably 2.5% by weight or more, particularly preferably 2.7% by weight or more, particularly preferably 2.9% by weight or more. When the amount of monomer (B) is within the above range, the polysiloxane resin can be uniformly dispersed or soluble in water. Further, the upper limit of the amount of monomer (B) is not particularly limited as long as the effect of the present invention is achieved, but is, for example, 50% by weight or less, preferably 30% by weight or less, and more preferably 20% by weight or less. % by weight or less.

In one embodiment of the present invention, the amount of the organopolysiloxane compound (A) is, for example, 30% by weight or more, preferably 35% by weight or more, based on the total amount of (A) to (C). It is more preferably 40% by weight or more, particularly preferably 43% by weight or more, particularly preferably 45% by weight or more. When the amount of the organopolysiloxane compound (A) is within the above range, high weather resistance can be achieved when used as a paint. Further, the upper limit of the amount of the organopolysiloxane compound (A) is not particularly limited as long as the effects of the present invention are achieved, but is, for example, 95% by weight or less, preferably 90% by weight or less, and more preferably, It is 85% by weight or less.

In one embodiment of the present invention, the content of monomer (C) is, for example, 6% by weight or more, preferably 7% by weight or more, based on the total amount of (A) to (C). The content is more preferably 8% by weight or more. When the content of the monomer (C) is within the above range, it has the effect of imparting elasticity to the coating film. Further, the upper limit of the content of the monomer (C) is not particularly limited as long as the effects of the present invention are achieved, but is, for example, 50% by weight or less, preferably 48% by weight or less, and more preferably, It is 47% by weight or less.

In one embodiment of the present invention, the production method further includes condensing an alkoxysilane compound and an alkoxysilane compound having a radically polymerizable unsaturated group to produce the organopolysiloxane having the radically polymerizable unsaturated group. The method may include a step of obtaining compound (A).

As the alkoxysilane compound and the alkoxysilane compound having a radically polymerizable unsaturated group, for example, those described above (structural unit (a)) can be used.

The condensation in this step can be performed by a method known in the art. For example, it is carried out by adding water and a catalyst for hydrolysis and condensation of alkoxysilyl groups to a mixture containing an alkoxysilane compound and an alkoxysilane compound having a radically polymerizable unsaturated group. When using a solvent in the condensation step, it is preferable to use a non-aqueous solvent.

As the catalyst for the hydrolysis and condensation of the alkoxysilyl group in this step, for example, the above-mentioned catalysts can be used.

The condensation of the alkoxysilane compound and the alkoxysilane compound having a radically polymerizable unsaturated group is as described in (constituent unit (a)) above.

In one embodiment of the present invention, the number of moles of water used in the condensation is 1.0 to 2.5 with respect to the total number of moles of the alkoxysilane compound and the alkoxysilane compound having a radically polymerizable unsaturated group. It can be double.

In one embodiment of the present invention, the alkoxysilane compound having a radically polymerizable unsaturated group to be subjected to the condensation may be 2 to 10% by weight based on the total alkoxysilane compound.

[5. Use]
This polysiloxane resin, this resin composition, and this aqueous solution can be used, for example, for the interior and exterior of buildings, for automobiles such as metallic bases or clear coatings on metallic bases, for direct coating on metals such as aluminum, stainless steel, and silver, for slate, concrete, etc. For direct coating of tiles, mortar, plasterboard, asbestos slate, asbestos board, precast concrete, lightweight cellular concrete, calcium silicate boards, tiles, bricks, etc., paints or top surfaces for glass, stone materials such as natural marble, granite, etc. It is suitably used as a processing agent.

The present invention is not limited to the embodiments described above, and various modifications can be made within the scope of the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. are also included within the technical scope of the present invention.

EXAMPLES Hereinafter, the present invention will be explained in more detail based on Examples, but the present invention is not limited to these Examples.

〔material〕
In the Examples and Comparative Examples, the following materials were used.

(component a)
Methyltrimethoxysilane: "Z-6033" manufactured by Dow Toray Industries, Inc.
Phenyltrimethoxysilane: "Z-6124" manufactured by Dow Toray Industries, Inc.
Dimethyldimethoxysilane: "Z-6329" manufactured by Dow Toray Industries, Inc.
γ-methacryloxypropyltrimethoxysilane: “A-174” manufactured by Momentive Performance Materials Japan LLC
γ-methacryloxypropylmethyldimethoxysilane: "Z-6033" manufactured by Dow Toray Industries, Inc.
(b component)
Pure water dibutyl phosphate: “DBP” manufactured by Johoku Chemical Industry Co., Ltd.
(c component)
Methyl methacrylate (abbreviation "MMA"): Manufactured by Mitsubishi Gas Chemical Co., Ltd. Butyl acrylate (abbreviation "BA"): Manufactured by Nippon Shokubai Co., Ltd. γ-(meth)acryloxypropyltriethoxysilane (abbreviation "TESMA"): Momentive Performance・“Y-9936” manufactured by Materials Japan LLC
Sodium acrylamide-t-butylsulfonate: "ATBS-Na" manufactured by Toagosei Co., Ltd., commercially available classification "monomer"
Sodium sulfoethyl methacrylate: “Antox MS-2N-D” manufactured by Nippon Nyukazai Co., Ltd., commercially available classification “emulsifier”
Sodium acrylate (abbreviation "AANa"): Manufactured by Asada Chemical Industry Co., Ltd., has a salt structure consisting of a weak acid and a strong base (does not have a salt structure consisting of a strong acid and a strong base), commercially available classification "monomer"
Adekastab SR-10: Manufactured by Adeka Co., Ltd., contains neither (meth)acryloyl group nor (meth)acrylamide group, commercially classified as "emulsifier"
2,2'-azobis(2,4-dimethylvaleronitrile): Made by Wako Pure Chemical Industries, Ltd., polymerization initiator 2-propanol: Made by Nacalai Tesque Co., Ltd. Pure water (component d)
Pure water 2-propanol: Nacalai Tesque Co., Ltd. Potassium persulfate: Mitsubishi Gas Chemical Co., Ltd. (component e)
2,2'-azobis(2,4-dimethylvaleronitrile): Wako Pure Chemical Industries, Ltd., polymerization initiator 2-propanol: Nacalai Tesque Co., Ltd. Potassium persulfate: Mitsubishi Gas Chemical Co., Ltd. (others) )
Pure water Titanium dioxide: “Tiepeke PFC105” manufactured by Ishihara Sangyo Co., Ltd.
Antifreeze agent: "Propylene glycol" manufactured by Kanto Chemical Co., Ltd.
Dispersant: “SMA1440H Solution” manufactured by Cray Valley, “Disperbyk-2090” manufactured by Byk Chemie Japan Co., Ltd.
Wetting and dispersing agent: "Dispex Ultra FA 4437" manufactured by BASF
Preservative: “Slout 99N” manufactured by Osaka Gas Chemical Co., Ltd.
Antifoaming agent: “AGITAN 295” manufactured by MUNZING CHEMIE
Thickener: “SN Thickener 612NC” manufactured by San Nopco Co., Ltd.
Film-forming aid: "CS-12" manufactured by JNC Corporation.

[Measurement and evaluation method]
Measurements and evaluations in Examples and Comparative Examples were performed by the following methods.

(Polymerization stability)
Polymerization stability (gelation/precipitation during polymerization) was evaluated based on whether fluidity was lost due to thickening during polymerization and stirring became impossible. The case where polymerization was carried out without any problems was rated as "fair".

(Aqueous solution stability)
When the copolymer was diluted with water so that the volatile component content was 40%, the aqueous solution stability (water displacement property) was evaluated by visually observing the copolymer. It was judged as "good" when it was uniformly dispersed or dissolved in water, and it was judged as "poor" when phase separation between the copolymer and water was observed.

(Aqueous solution appearance)
The aqueous solution of the copolymer obtained in each synthesis example was allowed to stand for one week at 25° C., and the appearance of the aqueous solution was evaluated by visually observing it.

(Storage stability)
A resin-containing aqueous solution adjusted to a solid content concentration of 40% was sealed in a glass bottle and left standing in a hot air dryer heated to 50°C, and when the glass bottle was tilted at 45 degrees, fluidity was confirmed in the solution inside. The storage stability (day of gelation at 50° C.) was evaluated using the gelation point at the time when gelatinization stopped.

(Gloss value)
The gloss value was measured with reference to Japanese Patent No. 5,695,950. Briefly, using a gloss meter Multi-Gloss 268 manufactured by Minolta Co., Ltd., the gloss value at an incident angle of 60° of a test piece prepared by the method described below was measured. The higher the gloss value, the better the appearance.

(Weatherability)
Weather resistance was evaluated with reference to International Publication No. 2016/052636 and Patent No. 5555449.

Briefly, an accelerated weathering test was conducted on a cured film on a test piece prepared by the method described below using a metal halide lamp type tester (manufactured by Daipra Wintes Co., Ltd., model KU-R5CI-A). The 60° gloss value of the cured film was measured before and after 400 hours of accelerated weathering test, and the gloss retention rate was calculated. The higher the gloss retention rate, the better the weather resistance.

The test conditions for the accelerated weathering test are as follows.

Illuminance: 85mW/ ^cm2
Irradiation 63℃ 50% 6 hours
Condensation 30℃ 98% 2 hours Shower 30 seconds before and after condensation.

[Synthesis examples 1 to 9]
(Cocondensate; a-1 and a-2)
Each cocondensate (a-1 and a-2) was synthesized using the various components listed in Table 1 in the amounts listed in Table 1.

Specifically, in a reactor equipped with a stirrer, a thermometer, and a reflux condenser, component a of the type and amount listed in Table 1 as a silane compound, followed by component b were charged, and the mixture was stirred at a reaction temperature of 105° C. for 3 hours. The reaction was carried out while the reaction was in progress, and each co-condensate (a-1 and a-2) was obtained.

(Acrylic graft cocondensate: A-1 to A-9)
Each acrylic graft cocondensate (A-1 to A-9) was synthesized using the various components listed in Table 2 in the amounts listed in Table 2.

Specifically, a reactor equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen gas introduction tube, and a dropping funnel was charged with the type and amount of component d listed in Table 2, and heated to 75°C while introducing nitrogen gas. After raising the temperature to , a mixed solution of component c of the type and amount listed in Table 2 was added dropwise at a constant rate from the dropping funnel over a period of 5 hours. Next, a mixed solution of component e having the type and amount listed in Table 2 was added dropwise at a uniform rate over 1 hour. Thereafter, the mixture was continuously stirred at 75° C. for 2 hours, and then degassed using a rotary evaporator until the nonvolatile components became 90% or more, and then diluted with water so that the nonvolatile components became 40%. The mixture was cooled to room temperature to obtain each acrylic graft cocondensate (A-1 to A-9).

[Synthesis example 10]
(Aqueous acrylic silicone copolymer emulsion: A-10)
Acrylic graft cocondensate (A-10) was synthesized using the various components listed in Table 2 in the amounts listed in Table 2.

Specifically, a reactor equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen gas introduction tube, and a dropping funnel was charged with the type and amount of component d listed in Table 2, and heated to 75°C while introducing nitrogen gas. After raising the temperature to , a mixed solution of component c of the type and amount listed in Table 2 was added dropwise at a constant rate from the dropping funnel over a period of 5 hours. Next, a mixed solution of component e having the type and amount listed in Table 2 was added dropwise at a uniform rate over 1 hour. Thereafter, the mixture was stirred at 75° C. for 2 hours and then cooled to room temperature to obtain an aqueous acrylic silicone copolymer emulsion (A-10).

[Production example of resin composition]
With reference to International Publication No. 2016/052636 and Patent No. 6059864, a resin composition for a pigment-containing coating agent was produced as an example of a resin composition. Briefly, each component was blended in the types and amounts shown in Table 3 to produce each pigment-containing resin composition for a coating agent.

[Preparation of test piece]
With reference to International Publication No. 2016/052636, test pieces for measuring and evaluating "gloss value" and "weather resistance" were prepared. Briefly, 0.4 parts by weight of diazabicycloundecene was added as a curing catalyst to 100 parts by weight of each resin composition for a pigment-containing coating agent prepared above, and Hypon Fine Primer II (Nippon Paint) was added as a primer. Coating was applied onto an aluminum plate (50 mm x 150 mm) coated with the product (manufactured by Manufacturer Co., Ltd.) using air spray so that the dry film thickness was approximately 40 μm, and dried for one week at 23°C and 50% RH. Got the board. Each coated plate was used as each test piece.

[Examples 1 to 8 and Comparative Example 2]
Using each copolymer and each test piece produced above, various parameters were measured and evaluated by the method described in the above [Measurement and evaluation method]. The results are shown in Table 4.

[Comparative example 1]
Using the copolymer (A-9) produced above, various parameters were measured and evaluated by the method described in [Measurement and evaluation method] above. The results are shown in Table 4.

〔result〕
From Table 4, Examples 1 to 8 have excellent polymerization stability, aqueous solution stability, aqueous solution appearance, and storage stability, which indicate performance as water-based paints, and also have gloss values and gloss retention rates that are related to weather resistance. It was good.

On the other hand, in Comparative Example 1, since a copolymer having no salt structure consisting of an acid and a base was used in the side chain, the aqueous solution stability (water displacement property) was poor, resulting in precipitation of the product. Ta.

Furthermore, in Comparative Example 2, since the copolymer in the form of an emulsion was used, the gloss value was low and the gloss retention rate was also poor.

The resin of the present invention can be used as a water-based paint and provides a coating film with excellent weather resistance. Therefore, the present invention can be suitably utilized in various fields of coating agents.

Claims (3)

An organopolysiloxane compound (A) having a radically polymerizable unsaturated group,
A monomer (B) having a salt structure consisting of an acid and a base and having a radically polymerizable group;
Optionally, a monomer (C) having a radically polymerizable group other than the above (A) and (B),
including the step of copolymerizing
Furthermore, the step of condensing an alkoxysilane compound and an alkoxysilane compound having a radically polymerizable unsaturated group to obtain the organopolysiloxane compound (A) having the radically polymerizable unsaturated group,
The alkoxysilane compound has the following general formula (I):
R ¹ _a -(Si(OR ² ) _4-a ) (I)
(In the formula, R ¹ is an alkyl group having 1 to 10 carbon atoms or an unsubstituted or substituted aryl group, R ² is each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and a is 0 It is an integer between ~3.)
A compound having a hydrolyzable silyl group represented by
The alkoxysilane compound having a radically polymerizable unsaturated group has the following general formula (II):
R ³ _b -(Si(OR ⁴ ) _4-b ) (II)
(In the formula, R ³ has a substituted alkyl group having 1 to 10 carbon atoms, an alkenyl group, or a polymerizable unsaturated group having a polymerizable unsaturated group, and may optionally have other substituents. It is an aryl group, each R ⁴ is independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and b is an integer of 1 to 3.)
A compound having a hydrolyzable silyl group represented by
The alkoxysilane compound having a radically polymerizable unsaturated group is 2 to 8% by weight based on the total alkoxysilane compound,
The monomer (B) includes sodium sulfoethyl methacrylate, sodium acrylamide-t-butylsulfonate, sodium 2-(methacryloyloxy)ethanesulfonate, sodium 2-(methacryloyloxy)polyalkylene oxide sulfonate, and sodium acrylamide-t-butylsulfonate. Sodium butylsulfonate, potassium 2-(methacryloyloxy)ethanesulfonate, potassium 2-(methacryloyloxy)polyalkylene oxide sulfonate, potassium acrylamide-t-butylsulfonate, calcium 2-(methacryloyloxy)ethanesulfonate, 2- (methacryloyloxy)calcium polyalkylene oxide sulfonate, calcium acrylamide-t-butylsulfonate, ammonium sulfoethyl methacrylate, ammonium acrylamide-t-butylsulfonate, ammonium 2-(methacryloyloxy)ethanesulfonate, 2-(methacryloyloxy) From the group consisting of ammonium polyalkylene oxide sulfonate, ammonium acrylamide-t-butyl sulfonate, sodium acrylate, potassium acrylate, calcium acrylate, ammonium acrylate, sodium methacrylate, potassium methacrylate, calcium methacrylate and ammonium methacrylate A method for producing one or more selected polysiloxane resins. The method for producing a polysiloxane resin according to claim 1, wherein the copolymerization is performed in a nonaqueous solvent. The method for producing a polysiloxane resin according to claim 2, further comprising a step of replacing the nonaqueous solvent with an aqueous solvent after the copolymerization step.