JPH04117473A - Coating composition - Google Patents

Abstract

PURPOSE:To prepare a coating compsn. giving a coating film excellent in hardness, the resistance to scratch, water, and chemicals, etc., by compounding a specific organoalkoxysilane, a specific vinyl resin, a specific tetraalkyl silicate, a specific Al compd., water, and an additive for adjusting the solid content. CONSTITUTION:100 pts.wt. compd. comprising an organoalkoxysilane of the formula RSi(OR<1>)3 (wherein R is a 1-8C org. group: and R<1> is 1-5C alkyl or 1-4C acyl) and/or a partial condensation product thereof, 10-300 pts.wt. silylated vinyl resin having, at the terminal or on the side chain of the molecule, at least one silyl group having a hydrolyzable group directly attached to Si (e.g. an acrylic polymer having trialkoxysilyl groups), 0.5-30 pts.wt. tetraalkyl silicate of the formula Si(OR<2>)4 (wherein R<2> is 1-4C alkyl), 0.01-30 pts.wt. compd. comprising an Al compd. of the formula Al(OR<3>)n[OR(R<4>)<(4278)>=CHCOR<5>]3-n (wherein R<3> and R<4> are each alkyl; R<5> is R<3> or alkoky; and (n) is 0-3) and/or a partial hydrolysis product thereof, 10-70 pts.wt. water, and a proper amt. of an additive for adjusting the solid content (e.g. isopropanol) are compounded.

Description

Detailed Description of the Invention (a) Industrial Application Field The present invention provides heat-resistant,
The present invention relates to a coating composition that has excellent abrasion resistance, chemical resistance, water resistance, weather resistance, etc. and is suitable for forming a thick coating film with high hardness and high gloss.

(b) Conventional technology The surfaces of various molded objects such as metals and ceramics are coated with a composition consisting of a silicone compound and a noricone-modified acrylic resin to give them cosmetic properties, abrasion resistance,
Efforts are being made to improve chemical resistance, corrosion resistance, weather resistance, water resistance, anti-glare properties, etc. For example, JP-A-60
Japanese Patent Publication No. 135465 discloses a coating composition comprising a dispersion of organotrihydroquinonolane and coloiglunorica and a silicone-modified acrylic resin.

This composition is simply a mixture of a dispersion obtained by hydrolyzing methyltriethoquinonerane with water of aqueous phosphorus sol and a noricone-modified acrylic resin containing an alkokino group in a compatible solvent. Therefore, the cured film obtained by applying the composition cannot be said to be chemically homogeneous. Since the noricorn component and the silicone-modified acrylic resin cure independently, the coating film lacks water resistance, chemical resistance, adhesion, scratch resistance, and smoothness even though it has an anti-glare effect.

JP-A-61-277901 discloses a composition comprising a hydrolyzate of orthoethyl silicate and a vinyl polymer containing a noryl group as an anti-glare agent for synthetic resin plates. This composition is essentially the same as the composition described above, except that the polysiloxane consists of ethyl nosilicate. Therefore, the cured film obtained by applying the composition is heterogeneous, and although it has an anti-glare effect, it lacks water resistance, chemical resistance, adhesion, scratch resistance, and smoothness as a coating film. .

JP-A-64-1769 discloses a coating composition comprising an organopolynoroxane, a norconium compound, and a vinyl resin containing a noryl group. This composition forms a crosslink between the zirconium compound or organopolysiloxane and the vinyl resin containing a nolyl group,
A copolymer is provided which is a chemically composited organopolysiloxane and a vinyl resin containing a nolyl group. Therefore, the cured film obtained by applying the composition is homogeneous and has excellent smoothness, chemical resistance, and gloss. Furthermore, since the composition contains β-dinoketones which act as stabilizers, the composition has good storage stability. However, this composition
Since it is a copolymer of organopolysiloxane and a silyl group-containing vinyl resin, it has a low nranol content per copolymer molecule, that is, a low crosslinking density. Therefore, not only is the adhesion to the substrate poor, but the hardness of the coating film obtained by curing is also low.

In addition, the β-dinoketones or β-ketoesters used in the hydrolysis of the norconium compound may form a colored chelate compound with trace amounts of metal ions, especially iron ions, etc., during the preparation of the composition. There are restrictions on the raw materials, containers, equipment, etc. used during storage or film formation.

(c) Problems to be Solved by the Invention The present invention solves the above-mentioned conventional problems, and its purpose is to improve the production of metals, ceramics, glass, cement, plastics, wood, paper, fibers, etc. An object of the present invention is to provide a coating composition for coating a surface, which has the following properties.

■A coating composition with excellent transparency and gloss, high hardness, and capable of forming a coating film with excellent adhesion to the substrate; ■Alkali resistance, acid resistance, boiling water resistance, and solvent resistance. A coating composition that can form a coating film with excellent properties such as: ■Does not require long curing treatment at high temperatures when preparing a coating film, and does not require cracking when forming a relatively thick coating film. (1) A coating composition that has excellent weather resistance and can form a coating film that does not discolor, blister, or crack even when exposed outdoors for a long period of time.

(d) Means and action for solving the problems The coating composition for coating of the present invention has the following features: (1) (a) General formula R51(OR')3 (wherein R is an organic group having 1 to 8 carbon atoms) , R1 represents an alkyl group having 1 to 5 carbon atoms or an acyl group having 1 to 4 carbon atoms) and/or a partial condensate thereof, 100 parts by weight in terms of organoalcoquinone lan, ( b) 10 to 300 parts by weight of a silyl group-containing vinyl resin having at least one silyl group in one polymer molecule containing a silicon atom bonded to a hydrolyzable group at the terminal or side chain; (c) 10 to 300 parts by weight of water; 70 parts by weight, (d) General formula 5i(OR')4 (wherein, R1 is carbon number 1
05 to 30 parts by weight of a tetraalkyl silicate represented by (representing an alkyl group of ~4), (e) general formula A+(OR3), COC(R')=C
HCOR') 3-- (wherein R3 and R' are an alkyl group, R5 is an alkyl group or an alkokyne group, and n is 0 to 3
001 to 30 parts by weight of at least one selected from the group of aluminum compounds and partial hydrolysates of the aluminum compounds represented by This achieves the above objective.

The organoalkokinosilane and/or its partial condensate [component (a)] used in the composition of the present invention are silicon compounds containing an alkoke group represented by the general formula S i (OR' ) s and the general formula R91(OR1)3
It is an alkoxy group-containing partial condensate obtained by condensing an alkoxy group-containing silicon compound represented by the formula under hydrolysis conditions.

In the above formula, R is an organic group having 1 to 8 carbon atoms, and R1 is an alkyl group having 1 to 5 carbon atoms or an acyl group having 1 to 4 carbon atoms. If the number of carbon atoms in R and R1 is too large, the hydrolysis of the hydrolyzable group described below becomes extremely slow, and in some cases, hydrolysis does not proceed at all. The above R is an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, an aryl group such as a phenyl group, a tolyl group, a xylyl group, a ncroalkyl group such as a nocrohexynol group, and other γ-
Examples thereof include a chloropropyl group, a vinyl group, a γ-grindquinprovil group, a γ-methacryloyl oquinobrovir group, a γ-mercaptopropyl group, a γ-aminopropyl group, and a 3,4-evoquinone clohequinol group. Examples of R1 include methyl group, ethyl group, propyl group, butyl group, and acetyl group. Such organoalkoxysilanes include, for example, methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxinlan, methyltriethquinsilane, ethyltrimethoxylan, methyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, Phenyltrimethoxine lan, phenyltriethoxin lan, vinyltrimethoquinonolan, γ-glycidquinopropyltrimethoxin lan, γ-glitquinbrovir triethoquinone lan, γ-mercabutobropyl trimethoquinone lan, γ
Examples include -methacryloquine trimethoxinelan, γ-aminopropyltrimethoxinesolane, and 3.4 evoquinecyclohequinlethyltrimethoxinesilane. Preferably, methyltrimethoxysilane and/or methyltriethquinsilane are used. These organoalkoxysilanes can be used alone or in combination of two or more.

The production reaction of the partial condensate obtained by condensing the above-mentioned organoalkoxysilane under hydrolysis conditions can be carried out by a production method known per se, that is, by adding water to the above-mentioned organoalkoxysilane and condensing it. I can do it.

The silyl group-containing vinyl resin (component (b)) used in the composition of the present invention contains at least one noryl group having a silicon atom with a hydrolyzable group bonded to the terminal or side chain in one polymer molecule. It is a vinyl resin containing a silyl group. For example, such a silyl group-containing vinyl resin has the following formula:
R”).

(Here, R6 is a halogen atom, a hydrolyzable group such as an alkokino group, an aminoquine group, a phenoxy group, a thioalcoquine group, an amino group, R7 is a hydrogen atom or an organic group having 1 to 8 carbon atoms, and R8 is a valent hydrocarbon group, R
11 is a hydrogen atom or a monovalent hydrocarbon group; n of
represents a group selected from the group consisting of n-valent aliphatic hydrocarbon residues and substituted n-valent aliphatic hydrocarbon residues having at least one ether bond; an alkyl group, n=an integer of 1 to 4) or by copolymerization of a rough-curing polymerizable acrylate monomer represented by the following formula:

(RI I is a halogen atom, a hydrolyzable group such as an alkokino group, an acyloquino group, an aminoquine group, a phenoxy group, a thioalcoquino group, an amino group, R'' is a hydrogen atom or an organic group having 1 to 8 carbon atoms, n ; is an integer from 1 to 3) can be produced by reacting it with a vinyl polymer having a carbon-carbon double bond, and there are no particular limitations on the production method.

(Left below) Examples of the acryloquine-functional norane represented by the general formula (A) include 7-methacrylokydipropyltrimethoquinonerane, armethacrylokydipropyltrimethoquinonerane, armethacrylokydipropyltrimethoquinonerane, and armethacryloquine-functional norane. Examples include biltriethoxy 7rane and 7-methacryloquidibrovirtriisopropoxinrane.

One or more types selected from the group consisting of these are used.

Examples of the radically polymerizable monomer represented by the general formula (b) include acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, t-butyl acrylate, 2-hydroxyethyl acrylate, and 2-hydroxyethyl acrylate. −
Hydroxypropyl, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, monobutyl methacrylate, isobutyl methacrylate, glinone methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, trimethylamino methacrylate Monoacrylate monomers such as ethyl, methoxydiethylene glycol acrylate, methoxydiethylene glycol methacrylate, methquine tetraethylene methacrylate and allyl methacrylate, ethylene glycol no methacrylate, diethylene glycol no methacrylate, 1,3-butylene glycol noacrylate and 1,3-butylene glycol Noacrylate monomers such as noacrylate, triacrylate monomers such as trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate and tetramethylolmethane triacrylate; tetraacrylate monomers such as tetramethylolmethanetetraacrylate; and the like.

One or more types selected from the group consisting of these are used.

At least one of these acryloxy-functional silanes and at least one radically polymerizable monomer are mixed in a suitable solvent and copolymerized using a radical polymerization initiator to produce a hydrolysable noryl group-containing acrylic resin. Obtainable.

As the radical polymerization initiator, for example, penzoylberoquinde, dichlorobenzoylberoquinde, nort-
Perester compounds such as butyl peroxide, 2,5-no(beroquine benzoate) hexyne-3,13his(t-butylperoquine isopropyl)henzen, t-butylperbenzoate: azohisisobutyronitrile and dimethylazo Examples include azo compounds such as butyrate, and peroxides.

As the hydrosilane compound represented by the general formula (c),
For example, halogenated silane compounds such as methylnochlorane, ethylnochlorane, phenylnochlorane and trichlorane; methyldimethoquinosilane;
Alcoquine silane compounds such as methyljetoxinrane, ethylshedkinsilane, ethylshedkinsilane, phenyldimethoxinrane, trimethoxinrane and triethoxysilane; Aciloxinlan compound; Methyldiaminoquinsilane,
Examples include amitunolan compounds such as triaminosolane and triaminosolane. One or more selected from the group consisting of these are used.

As the vinyl polymer having a carbon-carbon double bond, those selected from among the acrylates having no hydroxyl group represented by the general formula (b), styrene, α-methylstyrene, vinyl chloride, vinyl acetate, etc. Carbon obtained by copolymerizing one or more vinyl compounds with a conjugated diene compound such as butadiene, isoprene, or chloroprene, and/or an acrylic acid derivative having a carbon-carbon double bond that does not participate in polymerization. - Vinyl polymers having carbon double bonds are preferred.

At least one of these hydrosilane compounds is carbon-
A hydrolyzable silyl group-containing vinyl resin (component (b)) can be obtained by adding it to a vinyl polymer having carbon double bonds by an appropriate method.

Specific examples of the hydrolyzable noryl group-containing vinyl resin used in the present invention include Zemlac manufactured by Kanekabuchi Chemical Co., Ltd., Cylyl manufactured by Toshiba Noricone Co., Ltd., and Norikono Acrylic Varnish. .

The blending ratio of the above-mentioned noryl group-containing vinyl resin (component (b)) is 10 to 300 parts by weight, preferably 15 to 200 parts by weight, based on 100 parts by weight of organoalkoxysilane. If the amount of the above-mentioned noryl group-containing vinyl resin is less than 10 parts by weight, the resulting coating film will not have sufficient chemical resistance, and cracks are likely to occur in a thick film. On the other hand, 300 weight! ! 1
gI! If it exceeds this value, the abrasion resistance and heat resistance will be poor, and the storage stability will be poor.

Water (component (C)) used in the composition of the present invention is an essential component for the hydrolysis reaction of organoalkoxysilane (component (a)) and silyl group-containing vinyl resin (component (b)). The proportion of water used is 1 part orgalialcoquinsilane.
10 to 70 parts by weight, preferably 2 parts by weight per 11 parts by weight of 00
It is 0 to 60 parts by weight. If the amount is less than 10 parts by weight, the coating film may not be sufficiently cured even if the resulting composition is applied. On the other hand, if the blending ratio exceeds 70 times Nil,
This is not preferable because the storage stability of the composition decreases.

As the water required for G2Z, tap water, distilled water, ion exchange water, etc. may be used. Preferably, distilled water or ion-exchanged water is used.

Incidentally, a catalyst may be added to the water in order to control or promote the hydrolysis reaction.

Such catalysts include mineral acids such as hydrochloric acid, sulfuric acid, and phosphoric acid;
Any organic acid such as formic acid, oxalic acid, acetic acid, etc. can be used.

The tetraalkyl silicate (component (d)) represented by the general formula 5i(OR2)4 used in the composition of the present invention improves the hardness of the cured coating film formed by applying the composition, or improves the hardness of the coating film and the base material. Improves adhesion with materials. In particular, it works to improve water resistance.

In the above formula, R1 represents an alkyl group having 1 to 4 carbon atoms.

Examples of such alkyl silicates include tetramethyl silicate, tetraethyl silicate, tetra-n-propyl silicate, tetra-i-propylsilicate,
Examples include tetra-n-butyl silicate, tetra-1-butyl silicate, and tetra-5ec-butyl silicate.

The blending ratio of the above-mentioned tetraalkyl silicate is 05 to 30 parts by weight, preferably 1 to 20 parts by weight, per 100 parts by weight of organoalkoxysilane! ! Department.

If the amount is less than 0.5 parts by weight, the hardness and water resistance of the resulting coating film will be low, while if it exceeds 30 parts by weight, cracks will easily occur in the resulting coating film.

General formula AI(OR3)n used in the composition of the present invention
The aluminum compound represented by [OC(R') = C)LCOR'] *-, the partial hydrolyzate of the aluminum compound (component (e)), the above-mentioned organoalkoxysilane (component (a)), silyl It acts as a reaction accelerator during the hydrolysis reaction of the group-containing vinyl resin (component (b)). Furthermore, it acts to form a crosslinking site between the organoalkoxyquinonelan and the silyl group-containing vinyl resin. Therefore, the aluminum compound may be blended during the hydrolysis reaction or after the hydrolysis reaction is completed.

In the above formula, R3 and R4 are alkyl groups, R5 is an alkyl group or an alkokino group, and n is an integer of 0 to 3. As such an aluminum compound, tree 1-
Propoquinoaluminum, tri-n-propoquinaluminum, tri-5ec = butoquinoaluminum, tri-n-butoquinoaluminum, 5ec-butoquinoaluminum isopropylate, tri-5ec = butoquinoaluminum, ethyl acetoacetate aluminum diisopropylate, aluminum tris (ethylacetoacetonate), aluminum tris (acetylacetonate), aluminum monoacetylacetonatohis (ethylacetonate), and partial hydrolysates of the aluminum compounds. These aluminum compounds and partial hydrolysates of the aluminum compounds can be used alone or in combination of two or more.

Note that the above-mentioned partial hydrolyzate of an aluminum compound can be obtained by adding water to a hydrophilic organic solvent containing an aluminum compound in an amount that does not cause precipitation or gel.

The blending ratio of the aluminum compound and the partial hydrolyzate of the aluminum compound is 0.01 to 30 parts by weight, preferably 0.1 to 20 parts by weight, per 100 parts by weight of the organoalkoxysilane. Less than 0.001 parts by weight,
The hardness and chemical resistance of the resulting coating film are low, and on the other hand, if it exceeds 30 parts by weight, the stability over time of the composition deteriorates. Moreover, cracks are likely to occur in the resulting coating film.

Solid content adjuster (component (f)) used in the composition of the present invention
) not only functions as a diluent to adjust the solid content concentration of the present invention, but also makes it applicable to various coating methods and improves the storage stability of the composition. Examples of such solid content adjusting agents include alcohol solvents, aromatic solvents, ketone solvents, ester solvents, and polyhydric alcohol solvents. For example, methanol, ethanol, n-propertool, i-propertool, n-butanol, 1-butanol, 5ec-butanol, Hensen, toluene, kiln, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate, ethylene glycol, methyl Examples include cellosolve, ethyl cellosolve, and butyl cellosolve.

These can be used alone or in combination of two or more.

The blending ratio of the solid content adjuster (component (f)) is appropriately determined depending on the purpose of viscosity adjustment, dilution, etc., and is not particularly limited. However, usually the total solids concentration in the composition is 10 to 50% by weight, preferably 15 to 40% by weight.
It is preferable to adjust it so that If it is less than 10% by weight, the solid content concentration is too low and pinholes are likely to occur in the coating film obtained by applying the resulting composition, and the coating film may not exhibit its long-lasting properties. On the other hand, if it exceeds 50% by weight, the solid content concentration will be too high and the storage stability of the composition will deteriorate.

The composition of the present invention further contains various additives as necessary.

For example, by adding extender pigments, colored pigments and using them as colored enamels, or by adding appropriate fillers,
It can also be used as a paint for forming anti-rust films, electrical insulating films, conductive films, far-infrared emitting films, far-infrared absorbing films, ultraviolet absorbing films, and the like.

In addition, various conventionally known additives such as various surfactants, Nran coupling agents, titanium coupling agents, acetylacetone, and dyes may also be included.

When preparing the composition of the present invention, (a) to (f)
The components may be mixed at once, and components (a) to (c) and (
After mixing component f), components (d) to (e) may be mixed, and after mixing component (a) and component (c), component (b), (
d) to (f) components may be mixed, and after mixing a part of the (e) component to the (a) to (c) components, the (d) component, the remainder of the (e) component, and the (f) component Even if they are mixed, the preparation method is not particularly limited.

A desired coating film is formed by applying the coating composition of the present invention onto various substrates and curing it. Target base materials include metals, ceramics, cement, glass, plastics, paper, fibers, and wood. The coating film can be cured under relatively mild conditions at approximately 80 to 200°C for 5 to 60 minutes, and a relatively thick coating film can be formed without cracking or peeling during curing. is possible.

The composition of the present invention comprises an organoalcoquinonelan (component (
The polyoloxane derived from a)) is coated on the substrate together with a noryl group-containing vinyl resin (component (b)), a tetraalkylene licade (component (d)) and an aluminum compound (component (e)), and cured. Because it forms a strong chemical bond, it does not impair its adhesion to the base material. Therefore, this coating film has properties that are significantly superior to those formed from a chemical copolymer of polynoloxane and a silyl group-containing vinyl resin.

As described above, by using the coating composition of the present invention, it has gloss, high hardness, weather resistance, solvent resistance, acid resistance,
A coating film with excellent alkali resistance and water resistance can be formed.

(e) Examples The present invention will be explained below using examples. In the examples, parts always indicate parts by weight, and percentages always indicate weight %.

Example 1 (a) Preparation of coating composition Add acrylic polymer (containing acrylic polymer, solid content 50%) tool, 20 parts of isopropanol, and 40 parts of water, heat to 70'C with stirring, and react for 8 hours.

Next, 40 parts of isopropanol, aluminum Tris (
A coating composition A was obtained by adding 2 parts of acetylacetonate and 4 parts of tetramethyl nosilicate.

(b) Evaluation of coating composition Apply it so that This was heated at 180° C. for 20 minutes, and the resulting cured coating film was evaluated on the following items. The composition of the coating material and the obtained results are shown in Tables 1 and 2, respectively, along with the evaluation results of the coating coating compositions obtained in Examples 2 to 5 and Comparative Examples 1 to 5, which will be described later.

[Coating film appearance] Evaluate the surface condition by visual observation.

[Adhesion] Evaluated by JI85400 substrate opening.

[Hardness] Evaluated by JI95400 pencil hardness.

[Solvent Resistance] Gauze is immersed in methanol, and the coating is rubbed 30 times and its condition is observed.

[Boiling Water Resistance] Observe the condition after immersing in boiling water at 98°C for 8 hours.

[Drop 1 mρ of an acid-resistant 35% sulfuric acid aqueous solution onto the coating film, let it stand for one day in a petri dish with a lid, then wash with water and observe the condition.

[An alkali-resistant 15% sodium hydroxide aqueous solution was dropped onto the coating film for 1 ma, and after leaving it in a petri dish with a lid for one day, it was washed with water and the condition was observed.

[Weather Resistance] A 1000 hour irradiation test was carried out using a weatherometer according to JIS K5400, and the condition was observed.

Examples 2 to 5 Using the compositions and reaction conditions shown in Table 1, the same procedure as in Example 1 was carried out to obtain coating compositions BE. The composition and evaluation results of the obtained coating composition are shown in Tables 1 and 2, respectively.

Comparative Examples 1 to 5 Coating compositions F-J were obtained by the same operations as in Example 1 using the compositions and reaction conditions shown in Table 1. The composition and evaluation results of the obtained coating composition are shown in Tables 1 and 2, respectively.

Example 6 100 parts of the coating composition A obtained in Example 1 was used as a binder, and 30 parts of titanium oxide (manufactured by Mihara Sangyo Co., Ltd., Tybake R-380) was blended, dispersed in a sand mill for 1 hour, and coated. A coating composition K was obtained. Next, paint composition K for coating obtained f2 was applied to a straight plate (JIS A3403).
A dry coating film was applied onto the surface using a spray device to a thickness of about 50 μm, and heated at 150° C. for 20 minutes to form a cured coating film.

These cured coating films were evaluated on the evaluation items shown in Example 1. The results are shown in Table 3 together with the evaluation results of coating compositions obtained in Examples 7 to 10 and Comparative Examples 6 to 10, which will be described later.

Examples 7 to 10 Examples 6 to 10 except that coating composition B-E prepared in Examples 2 to 5 was used instead of coating composition A.
Coating compositions L to ○ were obtained in the same manner as above, and evaluated in the same manner. The results are shown in Table 3.

Comparative Examples 6 to 10 Coating paint composition P was prepared in the same manner as in Example 6, except that the coating composition F-J prepared in Comparative Examples 1 to 5 was used instead of the coating composition. -T was obtained and evaluated in the same manner.

Display the results Shown in 3.

(The following is a blank space) (F) Effects of the Invention According to the present invention, as shown in the above examples, a coating film with excellent properties can be easily formed on the surface of a base material such as a metal or ceramic substrate. A coating composition is provided. In particular, the coating film obtained using the coating composition of the present invention has high hardness, excellent scratch resistance, gloss, and has excellent weather resistance, water resistance, chemical resistance, etc. It is excellent. It maintains high gloss even when left outdoors or under corrosive conditions, and does not discolor or deteriorate.
It has excellent properties that cannot be obtained with conventional coating compositions. Therefore, for example, it is extremely useful as a paint for coating exterior wall materials exposed to sunlight, equipment used under conditions that are prone to corrosion, and building materials that require aesthetic appeal.

Claims (1)

[Claims] 1. (a) General formula RSi(OR^1)_3 (wherein R is an organic group having 1 to 8 carbon atoms, R^1 is an alkyl group having 1 to 5 carbon atoms or a carbon number 100 parts by weight of an organoalkoxysilane and/or its partial condensate represented by (1 to 4 acyl groups) expressed as an organoalkoxysilane, (b) a silicon atom bonded to a hydrolyzable group at the terminal or side chain; At least one silyl group having
(c) 10 to 70 parts by weight of water (d) General formula Si(OR^2)_4 (wherein R^2 is an alkyl group having 1 to 4 carbon atoms) 0.5 to 30 parts by weight of a tetraalkyl silicate represented by (e) general formula Al(OR^3)_n [OR(R^4)=
CHCOR＾5〕_3_-_n (in the formula, R^3 and R^
4 is an alkyl group, R^5 is an alkyl group or an alkoxy group, n is an integer of 0 to 3), and at least one member selected from the group of partial hydrolysates of the aluminum compound is 0. .01 to 30 parts by weight, and (f) an appropriate amount of a solids content regulator.