JP2671443B2 - Resin composition for paint - Google Patents

Description

The present invention relates to a novel and useful coating resin composition. More specifically, a particular film-forming polymer,
It can be used as a water-based paint or a coating agent in various fields such as for building exterior and the like, for paper and fiber processing, etc., with a particulate polymer having a hollow or porous inside as an essential component. The present invention relates to a resin composition for a paint.

[Conventional technology]

As a coating composition for building exterior, having a waterproof property,
A high gloss type or matte type resin composition is common, respectively.

However, recently, in these fields, there is a strong demand for a composition having so-called moisture permeability.
That is, the conventional coating composition generally does not have such moisture permeability, and when this type of coating is applied to a building, the water vapor generated indoors is inevitable. When condensed inside, it becomes condensed water and stays inside the wall, and as a result, it lowers the heat insulating property of the structure, and when wood is used as a building, the wood is used. Cause various problems such as decay, deterioration of strength of building base material, and generation of mold and moss.

In addition, even if the coating composition has excellent waterproofing properties, when dew condensation occurs in the wall, the water tends to escape to the outside, causing blisters and peeling,
This is also a big problem. Especially in cold regions, the problem is even more serious as frost damage.

Therefore, it is strongly desired to develop a coating composition that allows water vapor to pass through but does not allow water droplets to pass through.

Of course, as a resin composition having such characteristics, a type containing a silicone resin has already been introduced, but it is still not perfect, and after all, what can be satisfied after all At present, there is no such thing.

[Problems to be solved by the invention]

Therefore, the present inventors have considered that there are various problems in the prior art as described above, and can transmit water vapor,
As a result of repeated intensive studies in search of a resin composition for coatings that does not allow water in the form of water droplets to permeate, the presence of a special fine particle polymer as described in detail below provides a product with satisfactory performance. The present invention has been completed by discovering the above.

[Means for solving the problem]

That is, the present invention has, as an essential component, an emulsion (I) of a polymer having an alkoxysilyl group in the polymer and being bonded to a water-dispersible colloidal silica through the alkoxysilyl group. It is intended to provide a resin composition for coating material, which comprises a fine particle polymer (II) having a hollow or porous structure and, if necessary, also comprises pigments (III).

Here, the polymer emulsion (I) is
An emulsion of a polymer which has a specific functional group (reactive group) called an alkoxysilyl group and which is bonded to a water-dispersible colloidal silica through such an alkoxysilyl group. In Although,
Specifically, 2 of various polymerizable unsaturated bond-containing monomers (hereinafter abbreviated as vinyl monomers) as described below.
2.0% of colloidal silica to 100.0 parts by weight of seeds or more
A water dispersion obtained by emulsion-polymerizing 400.0 parts by weight, preferably 5 to 400 parts by weight (in terms of solid content) in an aqueous system in the presence of an anionic surfactant and / or a nonionic surfactant. A polymer composition.

The "colloidal silica" referred to herein is a dispersion in water having SiO ₂ as a basic unit, and particularly refers to one having a particle diameter of 10 to 30 nanometers, but as a state of dispersion of such colloidal silica, It may be either acidic or basic, and can be appropriately selected depending on various conditions during emulsion polymerization.

Among them, first of all, as the acid side colloidal silica, "Snowtex O" [Nissan Chemical Industry Co., Ltd. product]
And the like. Next, as the basic colloidal silica, "Snowtex 20, 30, 40, C or N" (product of the same company) and the like are typical.

In the preparation of the polymer emulsion (I), the use of an alkoxysilyl group-containing vinyl monomer as shown below as one of the vinyl monomers can improve the compatibility between the organic polymer and the inorganic polymer. From the standpoint of improvement, a more stable water-dispersible polymer composition can be obtained, and it is also preferable from the standpoint of durability of the final coating film.

As such an alkoxysilyl group-containing vinyl monomer, vinyltriethoxysilane, γ- (meth) acryloyloxypropyltrimethoxysilane, γ- (meth)
Acryloyloxypropylmethyldimethoxysilane,
Typical examples are γ- (meth) acryloyloxypropyltriethoxysilane and γ- (meth) acryloyloxypropylmethyldiethoxysilane.

Other vinyl monomers copolymerizable with the alkoxysilyl group-containing vinyl monomer include the following.

(Meth) acrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid or citraconic acid or an acid anhydride group-containing vinyl monomer such as maleic anhydride or itaconic anhydride and an addition reaction with glycols. Various carboxyl group-containing vinyl monomers such as unsaturated bond-containing hydroxyalkyl ester monocarboxylic acids, such as the acid anhydride groups listed above, including α, β-ethylenically unsaturated mono- or dicarboxylic acids. Α, β-ethylenically unsaturated carboxylic acids such as vinyl monomers; 2-hydroxyethyl (meth) acrylate;
2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth)
Polycarboxylic acids such as maleic acid and fumaric acid, including hydroxyalkyl esters of (meth) acrylic acid such as acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate or polyethylene glycol mono (meth) acrylate Various hydroxyl-containing vinyl monomers represented by unsaturated group-containing polyhydroxyalkyl esters such as di-hydroxyalkyl esters or hydroxyalkyl vinyl ethers such as hydroxyethyl vinyl ether; (meth) acrylamide, N Carboxylic acid amide group-containing vinyl monomers represented by, for example, N-dimethyl (meth) acrylamide, N-alkoxymethylated (meth) acrylamide, diacetone acrylamide or N-methylol (meth) acrylamide; p-styrenesulfonamide, N-methyl-p-styrenesulfonamide or N,
Sulfonamide group-containing vinyl monomers represented by N-dimethyl-p-styrenesulfonamide and the like; N, N-dimethylaminoethyl (meth) acrylate or N, N-
N, N such as diethylaminoethyl (meth) acrylate
-Dialkylaminoalkyl (meth) acrylates, polyhydric carboxylic acid anhydride group-containing vinyl monomers such as those listed above, active hydrogen atoms and tertiary groups capable of reacting with the acid anhydride group-containing vinyl monomer Tertiary amino group-containing vinyl monomers typified by an adduct with a compound having an amino group; cyano group-containing vinyl monomers typified by (meth) acrylonitrile; So-called α, β such as (meth) acrylic acid hydroxyalkyl esters and polyvalent carboxylic acid dihydroxyalkyl esters
-Vinyl monomers containing a phosphoric acid ester bond obtained by condensation reaction of hydroxyalkyl esters of ethylenically unsaturated carboxylic acid with phosphoric acid esters; sulfones represented by 2-acrylamido-2-methylpropanesulfonic acid Acid group-containing vinyl monomers; C ₁ -C _{18 such as} methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate or cyclohexyl (meth) acrylate (Meth) acrylic acid alkyl esters having a linear, branched or cyclic alkyl group; styrene and various derivatives thereof such as styrene, α-methylstyrene, p-rert-butylstyrene or vinyltoluene, and benzyl (meth) ) Containing (substituted) aromatic nuclei such as acrylates Aromatic vinyl monomers typified by (meth) acrylic acid esters; maleic acid,
With unsaturated dicarboxylic acids such as fumaric acid or itaconic acid
Diesters with C _{1 to} C ₄ monohydric alcohols; various vinyl esters typified by vinyl acetate, vinyl benzoate or "Veoba" (vinyl ester of branched fatty acid manufactured by Ciel Co., Netherlands); Viscoat 8F, 8FM, 3
F or 3FM ”(fluorine-containing (meth) acrylates manufactured by Osaka Organic Chemical Industry Co., Ltd.), perfluorocyclohexyl (meth) acrylate, di-perfluorocyclohexyl fumarate or N-isopropyl perfluorooctanesulfonamide ethyl ( (Per) fluoroalkyl group-containing vinyl esters typified by (meth) acrylates; various olefins typified by vinyl chloride, vinylidene chloride, vinylidene fluoride, chlorotrifluoroethylene, ethylene, propylene or butadiene; ethylene Typical examples are glycol di (meth) acrylate, propylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, divinylbenzene, trivinylbenzene or diallyl phthalate. And monomers having two or more polymerizable unsaturated bonds in the molecule.

Using the above various materials, for example, JP-A-59-71316
The polymer emulsion (I) is prepared by emulsion copolymerization according to the method disclosed in JP
Is obtained.

In that case, it goes without saying that emulsifiers and polymerization initiators as described below are used.

Next, the above-mentioned hollow fine particle polymer or fine particle polymer (II) having a porous structure means fine particles which are obtained by emulsion polymerization of a vinyl monomer having a specific composition and which have hollow or porous inside particles. Prepared by the same applicant, for example, prepared in accordance with the method disclosed in JP-A-61-62510 or JP-A-62-169739, respectively. do it.

That is, the method disclosed in JP-A-61-62510 is roughly as follows.

0.1-90 parts by weight (in terms of solid content) of a copolymer emulsion (C) obtained by emulsion-polymerizing a polymerizable vinyl monomer (A) and optionally a polyfunctional crosslinking monomer (B) as seed particles. In addition, 99. of the polymerizable vinyl monomer (D) having a solubility parameter difference of 0.1 or more from the above polymer (C).
9-10 parts by weight and 0-5 of polyfunctional crosslinking monomer (E)
Emulsion polymerization is carried out by adding 0 part by weight to obtain a desired fine particle polymer having a hollow or porous structure. Examples of the monomer used here include various vinyl monomers as described above, and a monomer that satisfies the above-described conditions may be used.

Of the monomers used here, preferably, (A) and (D) are both α, β-ethylenically unsaturated carboxylic acid or salts thereof, in the total amount of each monomer. Content of less than 5% by weight is desirable. As the preparation method, an emulsion polymerization method as described below can be applied in the presence of an emulsifier, a polymerization initiator and water with a predetermined amount of monomers selected from each of the above-mentioned monomer groups.

Examples of the emulsifier used at that time include so-called surface-active substances such as anionic surfactants, nonionic surfactants, and cationic surfactants, as well as reactive emulsifiers and acrylic oligomers. However,
Among these, the use of a nonionic surfactant and an anionic surfactant is desirable because the formation of aggregates during polymerization is small and, in addition, a stable emulsion can be obtained.

Typical examples of such nonionic surfactants include polyoxyethylene alkylphenol ether, polyoxyethylene alkyl ether, polyoxyethylene higher fatty acid ester or ethylene oxide-propylene oxide block copolymer, and the like. Typical examples of the ionic surfactant include alkylbenzene sulfonic acid alkali metal salts, alkyl sulfate alkali metal salts and polyoxyethylene alkylphenol sulfate alkali metal salts.

Further, it goes without saying that a water-soluble oligomer composed of a polycarboxylic acid or a polysulfonate can be used instead of or in combination with the above-mentioned anionic surfactant.

Furthermore, a water-soluble polymer substance such as polyvinyl alcohol or hydroxyethyl cellulose can be used as a protective colloid.

The amount of the emulsifiers and the like listed above is suitably about 0.1 to 10% by weight based on the total amount of the monomers.

Next, the polymerization initiator is not particularly limited as long as it is one generally used in emulsion polymerization, and among them, a particularly representative one is a water-soluble agent such as hydrogen peroxide. Inorganic peroxides; persulfates such as ammonium persulfate or potassium persulfate; organic peroxides such as cumene hydroperoxide or benzoyl peroxide; or azobisisobutyronitrile, azobisisovaleronitrile or azobiscyano Examples thereof include azo compounds such as valeric acid, which may be used alone or in combination of two or more kinds. An appropriate amount of such a polymerization initiator is about 0.1 to 2% by weight based on the total amount of the monomers. It is needless to say that a method known as a so-called redox polymerization method using a combination of such a polymerization initiator with a metal ion and a reducing agent may be used.

Then, in the presence of water, preferably ion-exchanged water, or, if necessary, in the presence of this and an emulsifier, the vinyl monomers as they are, or in an emulsified state, by batch or divided addition, Alternatively, it is continuously dropped into a reaction vessel, and 0 to 10 in the presence of a polymerization initiator as described above.
The polymerization may be performed at a temperature of 0 ° C, preferably 30 to 90 ° C.

At that time, the ratio of the total amount of monomers to water is set so that the final solid content of the fine particle polymer (II) is in the range of 1 to 60% by weight, preferably 15 to 55% by weight. Should be.

In performing emulsion polymerization, a so-called seed polymerization method may be used in which emulsion particles are previously present in an aqueous phase and polymerized in order to grow and control the particle diameter. That is, it goes without saying that the seed particle emulsion may also be used in the preparation of the above-described "seed particle" copolymer emulsion (C).

Then, only vinyl monomers are additionally polymerized in the presence of the emulsion (C). In other words, vinyl monomers in the post-process (post-process) are so-called deposited and polymerized on the surface of the previously synthesized emulsion particles.

In order to obtain the target fine particle polymer (II) in this step, (C)
(D) in the presence of 0.1 to 50 parts by weight based on the solid content of the components
And 50 to 99.9 parts by weight of the monomer mixture constituting the component (E) may be polymerized.

In the polymerization of the components (D) and (E),
Since it is contrary to the gist of the present invention that so-called single particles composed of only the components (D) and (E) are produced in large amounts on a weight basis, additional use of emulsifiers should be avoided as much as possible. Yes, and if necessary, the amount of emulsifier should be kept below 5% by weight, preferably below 2% by weight of the total amount of components (D) and (E).

When the use amount exceeds 5% by weight, a large amount of emulsion particles containing only the components (D) and (E) are produced as by-products. For example, when the particle size molecule (particle size) is measured,
Since an emulsion having two peaks (a so-called bi-modal emulsion) is formed,
Not preferred.

The composition of the vinyl monomers in the thus obtained non-film-forming emulsion particles in which the inside of the particles is hollow or porous may be set so that the glass transition point is 50 ° C. or higher.

The method disclosed in Japanese Patent Application No. 62-169739 mentioned above as an alternative method is as follows.

That is, in preparing the aqueous emulsion,
An emulsion containing at least one vinyl monomer is emulsion-polymerized in the presence of an organic titanate compound to obtain a titanium atom-containing emulsion [hereinafter referred to as emulsion (F)]. , And then only vinyl monomers may be additionally polymerized in the presence of the emulsion (F). [Hereinafter, this is referred to as additional polymerization (G). ]
On the surface of the particles of the emulsion (F) containing the previously synthesized organotitanium compound, vinyl monomers in a later step (later step) are deposited and polymerized. When such a manufacturing method is adopted, the titanium atom or the titanium atom bonded to the organic compound is reliably fixed in the emulsion particles finally obtained, and the polymer in the subsequent step is titanium atom or the titanium compound bonded to the organic compound. A fine particle polymer emulsion having a hollow or porous structure in which the coating of the post-polymerization is complete because it is firmly bound via the atoms to the emulsion containing the previously polymerized titanium atom is obtained.

The organic titanate compound which is an essential component generally has a structure as described below.

Tetraisopropyl titanate, tetrabutyl titanate, tetrastearyl titanate, 2-ethylhexyl titanate, isopropyl tricumylphenyl titanate or isopropyl tri (N-aminoethyl-aminoethyl) titanate, and tetraisopropyl which is a condensate of various titanates. Organic titanium esters represented by titanate polymers or tetrabutyl titanate polymers; isopropyl tristearoyl titanate, isopropyl trioctanoyl titanate, isopropyl di (meth) acrylic isostearoyl titanate, diisostearoyl ethylene titanate or dicumylphenyloxyacetate titanate. Organic titanium acylates such as isopropyl tris (dioctylpyrophosphine) Titanate and its organic amine salt, isopropyl tri (dioctyl phosphate) titanate and its organic amine salt, bis (dioctyl pyrophosphate) oxyacetate titanate and its organic amine salt or bis (dioctyl pyrophosphate) ethylene titanate and its organic amine Organic titanium-phosphoric acid esters represented by salts and the like;
Organic titanium-sulfonic acid esters represented by isopropyl tridecylbenzene sulfonyl titanate and the like;
Alternatively, titanium acetylacetonate, titanium lactate, tetraisopropylbis (dioctylphosphite) titanate, tetraoctylbis (ditridecylphosphite) itanate, tetra (2,2-diallyloxymethyl-1-butyl) bis (ditridecyl) phosphite Organotitanium chelates such as titanates are mentioned. The organic amine salt referred to herein means an active acidic hydroxy group derived from a phosphoric acid ester present in the above-mentioned organic titanium-phosphoric acid esters, such as monoethylamine, diethylamine, triethylamine, butylamine, monoethanolamine, diethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine, triethanolamine and triethanolamine. Refers to those neutralized with organic amines such as ethanolamine or morpholine. The organic amines are preferably those which are volatile at room temperature. Neutralization may be carried out by mixing the acidic hydroxy group and the organic amine such that the molar ratio is equal to or more than the equivalent amount (the organic amine may be in excess), and mixed at room temperature or by cooling. In carrying out the present invention, among these, preferably, use is made of organic titanium-phosphate esters. The amount of the organic titanate compound used is 0.01 to 30 relative to the total weight of the organic titanate compound and the vinyl monomers used.
It is suitable that the content is in the range of wt%, preferably 0.05 to 25% by weight.

In order to obtain a hollow fine particle polymer or a fine particle polymer (II) having a porous structure according to the present method, as a first step, first, in the presence of various organic titanate compounds as described above, At least one of various vinyl monomers may be emulsion-polymerized, or a mixture of an organic titanate compound and vinyl monomers may be simultaneously emulsion-polymerized, and the steps up to here are the steps for preparing the emulsion (F). Is.

In this case, the amount of the vinyl monomer used is 70 to 9% based on the total weight of the organic titanate and the monomer.
9.99% by weight, preferably 75-99.5% by weight is suitable.

As the preparation method, respectively, the required amount of the organic titanate compound and the vinyl monomer as described above, an emulsifier,
Suitably, it is carried out in the presence of a polymerization initiator and water by an emulsion polymerization method as described below.

That is, the amount of emulsifiers used is 0.1 to 10 with respect to the total weight of the organic titanate compound and the vinyl monomers.
% By weight, and the amount of the polymerization initiator to be used is about 0.1 to 2% by weight based on the total weight as described above,
As the water, it is desirable to use ion-exchanged water, but in the presence of such ion-exchanged water, if necessary, in the presence of an emulsifier, an organic titanate compound and a vinyl monomer, separately, as is, or In an emulsified state, collectively, by divided addition, or continuously added dropwise to a reaction vessel, or mixed with an organic titanate compound and a vinyl monomer, as is, or in an emulsified state , All at once, or by divided addition, or continuously added dropwise to the reaction vessel, and then in the presence of various polymerization initiators as described above, 0 to 100 ° C, preferably 30 to 90 ° C. What is necessary is just to polymerize at a certain temperature.

The ratio between the total monomer amount and water is determined by the fine particle polymer (II).
Should be set to fall within the range of 0.1 to 60% by weight, preferably 15 to 55% by weight.

Further, preferably, in carrying out the emulsion polymerization, in order to grow and control the particles, it is of course possible to rely on a “seed polymerization method” in which emulsion particles are allowed to exist in the aqueous phase and polymerized. By such emulsion polymerization, the preparation step of the emulsion (F), which is the first step, is completed.

Then, in the presence of the emulsion (F) thus obtained, only the vinyl monomers are additionally polymerized.
The additional polymerization (G), which is the second step, is followed. In order to obtain the target fine particle polymer (II) in this step, 0.1 to 50 parts by weight of the component (F) based on the solid content, This (G)
What is necessary is just to polymerize 50-99.9 weight part of the monomer mixture which comprises a component.

The amount of the additional emulsifiers used in the polymerization of the component (G) is as described above.

The composition of the vinyl monomers in the emulsion particles constituting the emulsion of the fine particle polymer (II) thus obtained may be set so that the glass transition point is 50 ° C. or higher.

Further, a hollow fine particle polymer or a fine particle polymer having a porous structure (II) obtained by each method
Can be powdered by a known and commonly used method.

That is, for example, spray drying at a temperature of 100 to 250 ° C., tray or vat drying at a temperature of 50 to 70 ° C. or fluidized bed drying can be performed.

The extremely film-like fine particle polymer (II) obtained here
In general, the particle size of the resin powder, that is, the resin powder, is "secondary particle" itself which is an agglomerate of such primary particles, as opposed to "primary particle" which is a fine particle having the particle size at the time of preparing the fine particle polymer emulsion However, if necessary, this resin powder can be redispersed in water by using a dispersant such as an emulsifier or a protective colloid.

Therefore, in preparing the resin composition for coating material of the present invention, the fine particle polymer (II) may be used not only in the form of emulsion but also in the form of dry powder.

And as the blending amount of the fine particle polymer (II),
A suitable range is 0.1 to 30 parts by weight based on 100 parts by weight (in terms of solid content) of the polymer emulsion (I).

Further, to list only representative examples of the above-mentioned pigments (II), heavy calcium carbonate, light calcium carbonate, magnesium carbonate, precipitated barium sulfate,
Including mica or titanium oxide, cold water powder, rice powder, kaolin, clay, calcined clay, talc, silica sand, silica coal,
Inorganic pigments or fillers such as ultrafine silica, white carbon, asbestos, pulp powder, dolomite powder, zinc white or carbon black; or organic pigments such as phthalocyanine, azo or quinacridone, or dispersed pigments thereof. .

The content of the pigments (C) is appropriately in the range of 0 to 60%, preferably 5 to 30%, and more preferably 7 to 20% in terms of PVC (pigment volume concentration).

While the polymer emulsion (I) listed above is used as an essential component of the film-forming component, the fine particle polymer (II) is used as an essential component of the non-film-forming component, and if necessary, pigments ( III) is also compounded respectively to obtain the coating resin composition of the present invention.
The composition of the present invention composed of the components may further contain various additive components as shown below.

That is, "Chissosizer GS-12" (Chisso Corporation product), butyl carbitol acetate, butyl cellosolve, carbitol, hexylene glycol, cellosolve, dibutyl glycol phthalate, dibutyl phthalate, benzyl alcohol, diisopropyl succinate, "pical" (Pycal) 94 "(product of Atlas Chemical Company, USA) or" Dalya (Dalya
d) film forming aids such as "A" (product of Dow Chemical Company, USA); methanol, ethanol, propanol, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, hexane, heptane or cellosolve. Solvents such as acetate; phthalates such as dioctyl phthalate,
Aliphatic dibasic acid esters such as isodisyl succinate or dioctyl adipate, phosphoric acid esters such as tricresyl phosphate, glycol esters such as diethylene glycol benzoate, epoxy plasticizers such as epoxidized soybean oil, or chlorinated paraffins. Various plasticizers such as cations; various emulsifiers such as anionic or nonionic surfactants described above; salts of phosphoric acid derivatives such as pyrophosphoric acid, tripolyphosphoric acid or hexametaphosphoric acid, and polycarboxylic acids Various dispersants such as salt of Naphthalene Sulfonic Acid or salts of naphthalene sulfonic acid; Various dryness regulators such as Mineral Spirit or turpentine oil;
Freezing or thawing stability-imparting agents such as ethylene glycol, propylene glycol or glycerin; various antifoaming agents such as silicone-based or acrylic oligomers, or various preservatives, and the like. According to the above, it is appropriately determined.

The resin composition for a paint of the present invention thus obtained can be used as a general or industrial water-based paint such as for architectural exterior or woodwork, or as a coating agent for paper or textile processing, but is not limited thereto. Not something.

〔The invention's effect〕

Collaboration between a special polymer emulsion (I), which is bound to water-dispersible colloidal silica through an alkoxysilyl group of the polymer, and a special fine particle polymer (II) having a hollow or porous structure. Through the action, the resin composition for coating material of the present invention has excellent moisture permeability and has excellent water resistance, which has never been seen in the past.

〔Example〕

Next, the present invention will be described more specifically with reference examples, examples and comparative examples.
Unless otherwise noted, all are on a weight basis.

Reference Example [Preparation Example of Polymer Emulsion (I)] Vinyl Monomers 2-Ethylhexyl Acrylate 43 Parts Methyl Methacrylate 53〃 Acrylic Acid 2〃 γ-Methacryloyloxypropyltrimethoxysilane 2〃 Surfactants Sodium Lauryl Sulfonate 3 parts Colloidal silica "Snowtex 30" (Solid content = 30%) 150 parts Ion-exchanged water 160 parts Polymerization initiator ammonium persulfate 0.5 part Sodium hydrogen sulfite 0.2〃 Four-necked flask with surface activity as above Ingredients, colloidal silicas and ion-exchanged water are charged, the temperature is raised to 60 ° C. in a nitrogen stream, and then polymerization initiators such as those listed above are added. A mixture of such vinyl monomers was added dropwise over 3 hours. The temperature during the dropping reaction was controlled to 60 to 70 ° C.

After completion of the dropwise addition, the temperature was maintained within the same temperature range for 2 hours, the reaction was continued under stirring, and then cooled. Thereafter, the pH was adjusted to 8 to 9 with 14% aqueous ammonia, and the solid content was reduced to 35%. Thus, a stable, colloidal silica-containing emulsion was obtained. Hereinafter, this is abbreviated as emulsion (I-1).

Reference Example 2 [Preparation Example of Fine Particle Polymer (II)] This example was prepared according to the method disclosed in JP-A-61-62510.

In a reaction vessel equipped with a stirrer, a reflux condenser, a dropping funnel, a thermometer, and a nitrogen inlet tube, 100 parts of ion-exchanged water and "Emulgen 120" (a nonionic surfactant manufactured by Kao Corporation) were added. And 2 parts of “HITENOL N-08” (an anionic surfactant manufactured by the same company) and charged at an internal temperature of 80 parts.
The temperature was raised to 0 ° C to dissolve.

Next, 0.2 part of potassium persulfate, 10 parts of tert-butyl acrylate, 20 parts of styrene, 20 parts of methyl methacrylate and 3 parts of ethylene glycol dimethacrylate were added dropwise over 2 hours and reacted at the same temperature. Let
The reaction was continued at the same temperature for 1 hour to obtain an emulsion intermediate.

Thereafter, in the presence of the whole amount of this emulsion intermediate, at the same temperature, a mixture of 35 parts of styrene, 10 parts of n-butyl acrylate and 2 parts of ethylene glycol dimethacrylate and 0.2 part of potassium persulfate was added. The reaction was carried out by dropping over 2 hours, and the temperature was further maintained at the same temperature for 1 hour, followed by cooling.

Then, the pH was adjusted to 8.4 with 25% aqueous ammonia to obtain an emulsion of the fine particle polymer. It has a solids content of 51.0% and a "Coulter counter (Coulte
r Counter) N-4 ”, the average particle size (hereinafter the same) was 0.4 μm. Hereinafter, this is abbreviated as emulsion (II-1).

Reference Example 3 (same as above) This example was prepared according to the method disclosed in Japanese Patent Application No. 62-169739.

580 parts of ion-exchanged water was charged in the same reaction vessel as in Reference Example 2, and the temperature was raised to 85 ° C. Separately, into a surfactant solution prepared by dissolving 5 parts of sodium dodecylbenzenesulfonate in 100 parts of ion-exchanged water, 2 parts of bis (dioctylpyrophosphate) oxyacetate titanate, 186 parts of metal methacrylate and methacrylic acid were added. A monomer mixture composed of 10 parts and 2 parts of ethylene glycol dimethacrylate (the glass transition point of the copolymer obtained from the monomer mixture was 110 ° C.) was added and emulsified.
Then, this emulsion and a mixture of 2 parts of ammonium persulfate and 120 parts of ion-exchanged water were dropped into the reaction vessel of the same for 2 hours to cause a polymerization reaction. After the dropping was completed, the reaction was completed by keeping the same temperature for 1 hour and then cooled to obtain an emulsion intermediate.

It has a solids content of 20.5%, a pH of 1.5, and
The emulsion had an average particle size of 0.3 micron.

Then, add 274 of ion-exchanged water to the same reaction vessel.
Charge 9 parts and 195.1 parts of this emulsion intermediate to 85
The temperature was raised to ° C. Separately, 7 parts of sodium dodecylbenzene sulfonate was dissolved in 90 parts of ion-exchanged water, and a monomer mixture consisting of 58 parts of styrene and 2 parts of divinylbenzene was added thereto (the glass transition point of the monomer mixture). Is
It was 115 ° C. ) Was added to emulsify. The mixture of the emulsion, 3.6 parts of ammonium persulfate and 80 parts of ion-exchanged water was added dropwise to the reaction vessel in the same manner for 2 hours to carry out a polymerization reaction. After holding for a period of time and then cooling, an emulsion deposited and polymerized on emulsion particles containing an organotitanium compound was obtained.

It has a solids content of 40.3%, a pH of 2.5, and
It was an emulsion with an average particle size of 0.62 microns.
Hereinafter, this is abbreviated as emulsion (II-2).

Examples 1 to 3 and proportional examples 1 and 2
Mix in the mixing ratio shown in the table, and further, as a thickener, "Colacular VL" (product of Badishe Japan Co., Ltd.), "QR-708" (product of Rohm and Haas Company of the United States) and An equal mixture of methyl cellulose was added to the above mixture so as to be 3%, and the mixture was stirred and mixed until the viscosity became uniform to form a paint separately.

Then, for each paint, first, JISZ-0208
In accordance with the method of 1., a test piece for moisture permeability measurement was prepared, and then coated on a slate plate with a thickness of 3 mm and dried at room temperature for 1 week to prepare a test piece for water resistance measurement.

When the performance of the coating film was compared and examined for each test piece, the results as shown in the same table were obtained, but the resin composition for coating material of the present invention did not impair the moisture permeability at all and improved the water resistance. It is known to give a cured coating film.

Claims (4)

(57) [Claims] 1. An emulsion (I) of a polymer having an alkoxysilyl group in the polymer, which is bound to a water-dispersible colloidal silica through the alkoxysilyl group.
And a hollow fine particle polymer or a fine particle polymer (II) having a porous structure as an essential component, and if necessary, a pigment (III) as well. 2. An emulsion (I) of a polymer which has an alkoxysilyl group in the above-mentioned polymer and which is bonded to the water-dispersible colloidal silica through the alkoxysilyl group contains an alkoxysilyl group. 100.0 of polymerizable unsaturated bond-containing monomers containing vinyl monomer as an essential component
The resin composition for a paint according to claim 1, which is obtained by emulsion polymerization of parts by weight and 2.0 to 400.0 parts by weight of colloidal silica in terms of solid content. 3. The hollow fine particle polymer or the fine particle polymer (II) having a porous structure comprises a vinyl monomer (A) and, if necessary, a polyfunctional crosslinkable monomer (B). Of the copolymer emulsion (C) obtained by emulsion polymerization of
0.1 to 90 parts by weight (in terms of solid content) are used as seed particles, and 99.9 to 1 of vinyl monomers (D) having a solubility parameter difference of 0.1 or more from the copolymer emulsion (C).
The coating resin composition according to claim 1, which is obtained by adding 0 parts by weight and 0 to 50 parts by weight of the polyfunctional crosslinkable monomer (E) and subjecting to emulsion polymerization. 4. The hollow fine particle polymer or the fine particle polymer (II) having a porous structure as described above is obtained by emulsion-polymerizing at least one vinyl monomer in the presence of an organic titanate compound, and then, The resin composition for coating composition according to claim 1, which is obtained by carrying out additional polymerization (G) of only vinyl monomers in the presence of the obtained emulsion (F) containing a titanium atom.