JP3239523B2 - Polysiloxane composite polymer latex - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a latex in which an inorganic polymer and an organic polymer are compounded, and more particularly, to excellent weather resistance, stain resistance, water repellency, adhesion to inorganic substrates, The present invention relates to a polysiloxane composite polymer latex which has storage stability, and is excellent in suppression of skinning on the latex surface and excellent pigment dispersibility.

[0002]

2. Description of the Related Art Polysiloxanes have excellent weather resistance, stain resistance, water repellency, and adhesion to inorganic substrates. For example, as disclosed in JP-B-52-39691, polysiloxanes are used in the field of coatings and the like. Widely used for. However, when polysiloxane is used by blending with another carbon-based polymer, the above-mentioned useful properties are hardly exhibited due to poor compatibility between the two, and the field of use is limited. As a means for solving such problems and using polysiloxane for various applications, a dispersion of a low molecular weight polymer of polysiloxane is adjusted, and this is mixed with a dispersion of an organic polymer, Thereafter, a method of combining the two by removing the dispersion medium can be considered. However, in this method, the dispersion medium for dispersing the polysiloxane well is limited,
In addition, it is necessary to add a dispersing aid for stable storage for a long period of time, which lowers the compatibility between the polysiloxane and the organic polymer. Even if they are mixed as a dispersion, they have disadvantages such as a non-uniform mixing state when the dispersion medium is removed, and do not necessarily have industrially sufficient utility value.

In order to solve these problems, for example, Japanese Patent Application Laid-Open No. 3-45628 discloses a method in which an organic polymer particle dispersed in an aqueous dispersion medium absorbs the alkoxysilane, and then the condensation of the alkoxysilane is carried out. It has been proposed to obtain polymer particles in which a polysiloxane is complexed by allowing the reaction to proceed. But with this method,
In the obtained latex, the alkoxysilyl group in the alkoxysilane is hydrolyzed to produce alcohol, so that the surface of the latex becomes skinned and a smooth coating film cannot be obtained. In the case where is mixed, there is a problem that the pigment is agglomerated and dispersibility is poor.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above background, and has as its object to provide excellent weather resistance, stain resistance, water repellency, and adhesion to inorganic substrates. Another object of the present invention is to provide a polysiloxane composite polymer latex which has storage stability, suppresses skinning of the latex surface, and is excellent in pigment dispersibility.

[0005]

According to the present invention, 0.1 to 500 parts by weight of alkoxysilane is condensed in the presence of 100 parts by weight (solid content) of organic polymer particles dispersed in an aqueous dispersion medium. And an alcohol content in the latex is 5% by weight or less. Hereinafter, the present invention will be described in detail.

The aqueous dispersion of organic polymer particles used in the present invention is not particularly limited. For example, polystyrene latex, polybutadiene latex comprising dispersed particles having an average particle diameter of 0.05 to 10 μm obtained by emulsion polymerization. , A styrene-butadiene copolymer latex, an acrylic ester copolymer latex, a methacrylic ester copolymer latex, and any other known latex can be used. In addition, a known re-emulsified latex, a natural rubber latex or a concentrate thereof formed by re-dispersing a polymer obtained by solution polymerization or the like in water with an emulsifier can also be used.

In the present invention, a nonionic emulsifier, a cationic emulsifier, an amphoteric ionic emulsifier, a reactive emulsifier, an anionic emulsifier and the like can be used in the production of organic polymer particles, and a reactive emulsifier is particularly used. Is preferred. Examples of the anionic emulsifier include higher alcohol sulfate sodium salt, alkylbenzene sulfonate sodium salt, dialkyl succinate sodium sulfonate, sodium alkyldiphenyl ether disulfonate and the like. Of these, sodium dodecylbenzenesulfonate, sodium lauryl sulfate, and sulfates of polyoxyethylene alkyl (or alkylphenyl) ether are preferably used. Examples of the nonionic emulsifier include polyoxyethylene alkyl allyl ether. Generally, polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether and the like are used as the nonionic emulsifier.

As an amphoteric emulsifier, lauryl betaine is suitable. As the cationic surfactant, alkylpyridinyl chloride, alkylammonium chloride and the like can be used. Examples of the reactive emulsifier include sodium styrenesulfonate, sodium allylalkylsulfonate, and the like. Latemul S-180A (manufactured by Kao Corporation), Eleminor JS-2 (manufactured by Sanyo Chemical Industries, Ltd.)
AQUALON RN-20, AQUALON HS-10
(Daiichi Kogyo Seiyaku Co., Ltd.), Adecaria Soap SE-1
0N (manufactured by Asahi Denka Kogyo KK) and the like. The amount of the emulsifier to be used is usually 0 to 5 parts by weight per 100 parts by weight of the monomers constituting the organic polymer particles. In terms of hot water resistance, the soap-free type and the reactive emulsifier type are used. preferable.

The alkoxysilane used in the production method of the present invention has a general formula R _n Si (OR ') _4-n (where R is an organic group having 1 to 8 carbon atoms, and R' is an organic group having 1 to 5 carbon atoms). An alkyl group or an acyl group having 1 to 4 carbon atoms, n is 0 to 3
Which is an integer). Where R is
An organic group having 1 to 8 carbon atoms, for example, an alkyl group such as a methyl group, an ethyl group, an n-propyl group, an i-propyl group, and a γ-chloropropyl group, a γ-chloropropyl group, a vinyl group, 3,3-trifluoropropyl group,
γ-glycidoxypropyl group, γ-methacryloxypropyl group, γ-mercaptopropyl group, phenyl group,
3,4-epoxycyclohexylethyl group, γ-aminopropyl group and the like. In the formula, R ′ is an alkyl group having 1 to 5 carbon atoms or an acyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and a sec-butyl group. , T-butyl group,
An acetyl group and the like can be mentioned.

When the carbon number of R or R 'in the formula is increased, the water solubility is lowered, and the absorption rate of alkoxysilane to the organic polymer particles as seeds is lowered, which is not preferable. Specific examples of these alkoxysilanes include:
Tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, i-propyltrimethoxysilane, i-propyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-chloropropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane,
3,3,3-trifluoropropyltrimethoxysilane,
3,3,3-trifluoropropyltriethoxysilane,
γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyl Triethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, γ-aminopropyltrimethoxysilane, 3,4-epoxycyclohexylethyltrimethoxysilane, 3,4-epoxycyclohexylethyltriethoxysilane, dimethyldimethoxysilane,
Examples thereof include dimethyldiethoxysilane and diethyldimethoxysilane, and preferred examples include tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, dimethyldimethoxysilane, and dimethyldiethoxysilane.

These alkoxysilanes can be used alone or in combination of two or more, and can also be used in combination with other metal alkoxides such as titanium and aluminum. In addition, a known silane coupling agent can be used in combination as needed. Furthermore, these alkoxysilanes can be used by dissolving them in an organic solvent, if necessary.

In the present invention, the amount of the alkoxysilane used is 0.1 to 100 parts by weight of the organic polymer particles.
500 parts by weight, preferably 0.5 to 250 parts by weight, more preferably 1.0 to 100 parts by weight, and less than 0.1 part by weight results in poor weather resistance, stain resistance and water repellency of the latex film, while If it exceeds 500 parts by weight, storage stability will be poor. In the present invention, in producing the polysiloxane composite polymer latex, it is preferable to absorb the alkoxysilane in the organic polymer particles, and as a method, the alkoxysilane is batchwise or in the presence of the organic polymer particles. It is achieved by adding continuously or in divided portions and stirring well. The amount of the alkoxysilane absorbed by the organic polymer particles is at least 5% by weight, preferably at least 10% by weight, more preferably at least 30% by weight of the total alkoxysilane used.

In order to prevent the reaction from proceeding in a state where the absorption of the alkoxysilane is not sufficient, the pH of the reaction system is set at pH
4 to 10, preferably pH 5 to 9, more preferably p
H6 to 8 and the temperature is 90 ° C or less, preferably 70 ° C.
The alkoxysilane is desirably added and absorbed at a temperature of at most 50 ° C, more preferably at most 50 ° C, particularly preferably at most 30 ° C. The condensation reaction of the alkoxysilane absorbed in the organic polymer can be easily controlled by changing the reaction temperature and the hydrogen ion concentration, and the degree of polymerization of the polysiloxane can be adjusted. The condensation reaction of alkoxysilane can be performed at a temperature of 30 ° C. or higher, preferably 50 ° C. or higher, more preferably 70 ° C. or higher.

The average particle size of the polysiloxane composite polymer latex thus obtained is usually from 0.03 to
It is about 0.5 μm, preferably about 0.05 to 0.3 μm, and more preferably about 0.05 to 0.2 μm. The adjustment of the average particle size can be performed by appropriately selecting the type of the organic polymer particles, the absorption amount of the alkoxysilane, and the like.

The amount of alcohol in the polysiloxane composite polymer latex of the present invention is 5% by weight or less, preferably 3% by weight or less.
When the content is less than 5% by weight or less, the effect of suppressing the skinning of the latex surface and the effect of dispersing the pigment cannot be sufficiently obtained, and a smooth coating film cannot be obtained. In such a case, a problem such as aggregation of the pigment or the like occurs. In the present invention, the latex is a polysiloxane composite polymer dispersed in water or an aqueous solvent, and the amount of alcohol in the present invention is all that is present in the latex regardless of the solid content in the polysiloxane composite polymer latex. Shows the total amount of alcohol. In the present invention, when the alcohol content of the polysiloxane composite polymer latex exceeds 5% by weight, it is necessary to remove the alcohol after the latex is produced. The method of removing the alcohol is not particularly limited, but a method of removing the alcohol by heating the obtained latex is preferable. The removal of alcohol is desirably performed at a temperature of 50 ° C. or higher, preferably 70 ° C. or higher, and may be performed under normal pressure or reduced pressure. The removal of the alcohol may be performed simultaneously with the hydrolysis reaction, or may be performed after the hydrolysis reaction or the condensation reaction is completed.

A crosslinking agent can be added to the polysiloxane composite latex of the present invention. Here, as a crosslinking agent, amino resin, phenol resin, epoxy resin,
Examples thereof include thermosetting resins such as alkyd resins and unsaturated polyesters, organic crosslinking agents such as isocyanate compounds, blocked isocyanate compounds, polyhydric alcohols and aziridine compounds, and inorganic crosslinking agents such as metals or metal compounds. These crosslinking agents are usually
Although it can be used at a curing temperature of 280 ° C., it is preferable to use amino resins, phenolic resins, blocked isocyanate compounds and the like at a curing temperature of 100 ° C. or higher.

Examples of the amino resin include fully alkylated methylated melamine resins such as hexamethoxymethylated melamine resin, partially alkylated methylated melamine resins, benzoguanamine resins, and alkyl etherified urea resins. Examples of the isocyanate and the blocked isocyanate include tolylene diisocyanate and its hydrogenated product and adduct, diphenylmethane diisocyanate and its hydrogenated product, triphenylmethane triisocyanate and its hydrogenated product, hexamethylene diisocyanate, xylylene diisocyanate and its hydrogenated product , Isophorone diisocyanate, dianisidine diisocyanate, tolidine diisocyanate, blocked polyisocyanate in which isocyanate groups are blocked, and an arbitrary mixture thereof.

Examples of the phenol resin include dimethylol resin, polymethylol phenol resin, phenol formamide resin, methylol phenol formamide resin, and dimethylol phenol formamide resin. Epoxy resins include ethylene glycol diglycidyl ether, hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, glycerin diglycidyl ether, glycerin polyglycidyl ether, diglycerin polyglycidyl ether, sorbitol polyglycidyl Ether, polyglycidyl ether of polyhydric alcohol such as hydrogenated bisphenol A / diglycidyl ether or bisphenol A / diglycidyl ether, or p-
Examples thereof include glycidyl ether of oxybenzoic acid, diglycidyl phthalate or hexahydrophthalic acid / diglycidyl ester, an epoxy resin containing a hydantoin ring, and a vinyl polymer having an epoxy group in a side chain.

Examples of the metal compound include oxides or salts of metals such as zinc, zirconium, magnesium, copper, iron, cobalt, nickel, aluminum, cadmium and titanium, and carbonates, acetic acids, formic acids, glutaric acids, and the like.
It is obtained by dissolving in an acid such as benzoic acid or oxalic acid, or by adjusting the pH of an aqueous solution of these acids and a polyvalent metal compound to 7 to 11 with ammonia, amine, or the like. Shaped forms can also be included. The polyvalent metal compound is an oxide or salt of zinc ammonium carbonate, ammonium zirconate, zinc, or zirconium. Those capable of forming a complex with the amine include morpholine, monoethanolamine, ethylenediamine, and diethylaminoethanol. In addition, general complexing agents, for example, complexans such as ethylenediaminetetraacetic acid, glycine, and alanine can also be used.

As the aziridine compound, tris-
2,4,6- (1-aziridinyl) -1,3,5-triazine, tris [1- (2-methyl) aziridinyl] phosphine oxide, hexa [1- (2-methyl) -aziridinyl] triphosphatriazine and the like Is mentioned.
The amount of the crosslinking agent to be used is 0.1 to 100 parts by weight, preferably 5 to 80 parts by weight, more preferably 10 to 70 parts by weight, based on 100 parts by weight of the polysiloxane composite polymer latex. If the crosslinking agent is less than 0.1 part by weight, the latex film has poor stain resistance, while if it exceeds 100 parts by weight, the adhesion of the latex film to the inorganic substrate and the storage stability of the latex may be poor. The crosslinking agent is
It may be added during the production process of the polysiloxane composite polymer latex, or may be added after the production of the polysiloxane composite polymer latex. May be added after the production.However, in order to suppress the generation of coagulate during the production of the polysiloxane composite polymer latex and maintain the polymerization stability, the crosslinking agent is used in the production process of the polysiloxane composite polymer latex. It is preferable not to add.

When the polysiloxane composite polymer latex of the present invention is used for coating, the following additives can be added according to the purpose. As the additive, first, in order to improve film forming properties, wettability, alcohols such as methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, amyl alcohol, hexyl alcohol, methyl cellosolve, ethyl cellosolve, propyl cellosolve, Organic solvents such as butyl cellosolve, hexyl cellosolve, methyl carbitol, ethyl carbitol, methyl cellosolve acetate, ethyl cellosolve acetate, and tribubutoxymethyl phosphate can be used. The amount of the organic solvent used is from 0 to 20% by weight, preferably from 0 to 1% by weight in the total composition.
0% by weight, more preferably 0 to 5% by weight.

Further, as additives other than the above-mentioned additives,
Water-soluble polyester resins commonly used as water-soluble resins, water-soluble or water-dispersible epoxy resins, water-soluble or water-dispersible acrylic resins, carboxylated aromatic vinyl resins such as styrene-maleic acid resins, urethane resins and the like In addition, a lubricant, an antifoaming agent, a wetting agent, a leveling agent, a pigment, and the like can be further used. The amount of the additive is 50 parts by weight or less, preferably 40 parts by weight or less, based on 100 parts by weight of the polysiloxane composite polymer latex (solid content). The coating agent using the polysiloxane composite polymer latex of the present invention forms a coating excellent in hot water resistance, flexibility, hardness, heat resistance, stain resistance, adhesion to a substrate, etc. It can be used for both paints, and can be used for coating materials such as wood, metal, concrete, plastic, ceramics, slate, marble, porcelain, gypsum and leather. These coating agents are particularly suitable for building interiors, building exteriors, steel structures, concrete structures, roofs, building materials, PCMs, automotive coatings, can coatings, aluminum coatings, and coating agents. Besides, for adhesive, floor polish, cement admixture, carpet backing agent, sealant,
Can also be used for paper coating, impregnation, fiber coating, etc.

[0023]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples unless it exceeds the gist. In the examples, parts and% indicating percentages are based on weight. The measurement of various physical properties in the examples was based on the following methods.

Conversion The conversion of the condensation of alkoxysilane was measured by the gravimetric method. Alcohol Amount The alcohol amount in the latex was measured using a gas chromatograph 663 manufactured by Hitachi, Ltd. Weather resistance, stain resistance Sunshine weather meter [manufactured by Suga Test Instruments Co., Ltd.
WEL-SUN HC type] (63 ° C.)
The gloss retention and the stain resistance after exposure for 0 hour were examined. For the gloss, a 60 ° specular gloss was measured based on JIS K5400. The stain resistance was determined by visually observing the external appearance, and those with good external appearance were evaluated as ◎, those with normal appearance were evaluated as ○, those with slight dirt were evaluated as Δ, and those with conspicuous dirt were evaluated as x. Distilled water was dropped on the contact angle (water-repellent) latex film, and the contact angle was measured using a contact angle measuring test device manufactured by Elma Optical Co., Ltd. An adhesive latex is coated on an aluminum plate at a thickness of 30 μm,
According to IS K 5401, a 100 mm grid test was performed, the peeling state was confirmed with a cellophane tape, and the number was indicated by the number of adhesions out of 100 pieces. The state of the storage-stable latex after storage for 3 months was visually evaluated, and those having no abnormality were evaluated as ○, and those in which separation, coagulation, etc. were observed were evaluated as ×. Smoothness of coating film (skinning of latex surface) Latex is coated on a glass plate, and the smoothness of the coating film surface after 24 hours is visually evaluated. The surface was slightly marked with cracks due to skinning, and the surface was marked with X. Pigment dispersibility The paint was formulated according to the following formulation, and the dispersion state of titanium oxide was visually evaluated. A sample having good dispersion was evaluated as ○, a sample showing slight aggregation of titanium oxide as Δ, and a sample showing noticeable aggregation of titanium oxide. Is indicated by x.

<Water-based paint formulation> Addition order Product name Addition amount (parts) 1 Ion-exchanged water 3 2 Dispersant 5 (Rohm & Hass Co., Orotan 731SD) 3 Titanium oxide 27 (Ishihara Sangyo Co., Ltd., Taipaque CR-97 4) Polysiloxane composite polymer latex 60 (50% solid content) 5 Plasticizer 3 (Texanol CS-12, manufactured by Chisso Corporation) 6 Thickener (ASE-60, manufactured by Nippon Acrylic Chemicals, Inc.) 2

(Example 1) A heater and a nitrogen gas introducing device were attached to a 100-L stainless steel autoclave equipped with a stirrer, a thermometer and a monomer addition pump, and 70 parts of ion-exchanged water were attached to the autoclave. 0.3 part of potassium persulfate was charged, the gas phase was replaced with nitrogen gas for 15 minutes, and the temperature was raised to 80 ° C. In a separate container,
30 parts of ion-exchanged water, 1.0 part of Adekaria Soap SE-10N (manufactured by Asahi Denka Kogyo KK) as a reactive emulsifier,
Each of the vinyl monomers shown in Table 1 was mixed and stirred to prepare a pre-emulsion, and the pre-emulsion was continuously dropped into the autoclave over 3 hours. During the dropping, nitrogen gas was introduced, and the autoclave was maintained at 80 ° C. After completion of the continuous dropping, the mixture was further aged at 85 to 95 ° C. for 2 hours, cooled to 25 ° C., and adjusted to pH 7 with aqueous ammonia to obtain organic polymer particles. Next, the autoclave was closed, 30 parts of tetraethoxysilane was added, the mixture was vigorously stirred for about 1 hour, the temperature was further raised to 80 ° C., and the reaction was continued with stirring for 3 hours. Latex solids concentration of 4
The condensation conversion of alkoxysilane was 7.2%, and the alcohol concentration was 9.2% in the latex. Thereafter, the pressure was reduced to 500 mmHg, and the internal temperature of the autoclave was reduced to 60 mm.
Stirring was continued for 2 hours while the temperature was raised to ℃. The solids concentration of the latex was 56.6%, and the alcohol concentration was 2.9% in the latex. Thereafter, the mixture was cooled, and the solid content of the latex was adjusted to 50% with ion-exchanged water.
The mixture was filtered through a 00 mesh wire net to obtain a polysiloxane composite polymer latex. When the average particle diameter of the obtained polysiloxane composite polymer latex was measured using a Nanosizer manufactured by Coulter Corporation, it was 0.15 μm.
The storage stability of the polysiloxane composite polymer latex thus obtained and the smoothness (skinning of the surface) of the coating film during latex coating were evaluated. Further, the polysiloxane composite polymer latex was blended with a paint in the same manner as in the evaluation of the pigment dispersibility to obtain a water-based paint. At the time of paint formulation, pigment dispersibility was evaluated. # 5
A tin plate of No. 0 was coated using a bar coater so as to have a film pressure of about 5 μm, and baked at 210 ° C. for 10 minutes to form a test piece. Weather resistance, stain resistance, water repellency, and adhesion of the coating film to an inorganic substrate Was evaluated. Table 1 shows the results.

(Example 2) In Example 1, sodium dodecylbenzenesulfonate (1.0%) was further added as an emulsifier.
In the same manner as in Example 1 except that the parts and the amounts of the organic polymer particles and the alkoxysilane were changed as shown in Table 1, a polysiloxane composite polymer latex and a test piece were obtained. . Table 1 shows the evaluation results of the polysiloxane composite polymer latex) and the test piece. (Example 3) In Example 1, 1.0 part of sodium lauryl sulfate and 1.0 part of polyoxyethylene nonyl phenyl ether were used as emulsifiers, and the types and charge amounts of organic polymer particle components and alkoxysilane were shown. A polysiloxane composite polymer latex and a test piece were obtained in the same manner as in Example 1 except for changing as shown in FIG. Table 1 shows the evaluation results of the polysiloxane composite polymer latex and the test piece.

Example 4 In Example 1, after the production of the polysiloxane composite polymer latex, 100 parts (in terms of solid content) of the polysiloxane composite polymer latex were stirred while the melamine resin composition (manufactured by Mitsui Cyanamid Co., Ltd.) was used.
"Cymel 303", 10 parts, Fujii Yoshitsusho Co., Ltd., "2
Example 1 except that 0.2 part of ammonium salt of “625A” and 8 parts of water were gradually added and stirred for 1 hour or more.
In the same manner as in the above, a melamine resin-containing polysiloxane composite polymer latex and a test piece were obtained. Table 1 shows the evaluation results of the melamine resin-containing polysiloxane composite polymer latex and the test piece. (Example 5) In Example 1, after the production of the polysiloxane composite polymer latex, 100 parts (in terms of solid content) of the polysiloxane composite polymer latex were stirred while an oxazoline-based polymer crosslinking agent (“K -1020
E) 20 parts), then stir for 1 hour or more,
An oxazoline-based polymer crosslinking agent-containing polysiloxane composite polymer latex and a test piece were obtained in the same manner as in Example 1, except that the baking temperature was changed to 70 ° C. for 48 hours. Table 1 shows the evaluation results of the oxazoline-based polymer crosslinking agent-containing polysiloxane composite polymer latex and test pieces.

[0029]

[Table 1]

Comparative Example 1 A polysiloxane composite polymer latex and a test piece were obtained in the same manner as in Example 1 except that the alcohol was not removed by heating. Table 2 shows the evaluation results of the polysiloxane composite polymer latex and the test piece.
From the results in Table 2, the alcohol content was 5% by weight in the latex.
From the above, it can be seen that the coating film has poor smoothness and pigment dispersibility. (Comparative Examples 2 and 3) A polysiloxane composite polymer latex and a test piece were obtained in the same manner as in Example 1 except that the charged amount of the alkoxysilane was changed as shown in Table 2. Table 2 shows the evaluation results of the polysiloxane composite polymer latex and the test piece. From the results shown in Table 2, when the charged amount of the alkoxysilane is less than 0.1 part, the weather resistance and the stain resistance are inferior.
It can be seen that storage stability is inferior when the amount exceeds part.

Comparative Example 4 Tetraethoxysilane 100
And 0.3 part (in terms of solid content) of sodium dodecylbenzenesulfonate having a concentration of 10% was diluted with distilled water to give 2 parts.
The mixture was put into a reaction vessel equipped with a reflux condenser and a stirrer, and mixed well with stirring. Then, the reaction vessel is
C. and reacted for 3 hours while replacing with nitrogen.
A transparent polysiloxane aqueous composition having a conversion of 99% was obtained. Furthermore, in the same manner as in Example 1, except that alkoxysilane was condensed in the presence of the organic polymer particles and 20 parts (in terms of solid content) of an aqueous polysiloxane composition was mixed instead. A polysiloxane-containing latex and a test piece were obtained. Table 2 shows the evaluation results of the polysiloxane-containing latex and the test piece.
Shown in From the results in Table 2, it can be seen that mere mixing with polysiloxane results in poor storage stability.

[0032]

[Table 2]

[0033]

The polysiloxane composite polymer latex of the present invention has excellent weather resistance, stain resistance, water repellency, adhesion to inorganic substrates, storage stability, and suppresses skinning of the latex surface. And excellent pigment dispersibility,
In particular, it can be suitably used as a coating agent for wood, paper, synthetic resin, glass, fiber, metal, concrete, mortar, cement, slate, marble, porcelain, gypsum, leather and the like.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08G 77/42 C08L 83/04 C08L 83/10

Claims (1)

(57) [Claims] 1. A polysiloxane composite polymer latex obtained by condensing 0.1 to 500 parts by weight of alkoxysilane in the presence of 100 parts by weight (solid content) of organic polymer particles dispersed in an aqueous dispersion medium. Wherein the alcohol content of the latex is 5% by weight or less.