JPH01115966A - Composition for coating - Google Patents

Abstract

PURPOSE:To obtain the subject composition curable at low temperature, providing a coating film having excellent alkali resistance and water resistance, containing an alkoxysilane, specific vinyl resin and reactive functional organopolysiloxane. CONSTITUTION:(A) 10-80pts.wt. calculated as alkoxysilane of an alkoxysilane shown by the formula RnSi(OR')4-n (R is 1-8C oraganic group; R' is 1-5C alkyl or 1-4C acyl; n is 0 or 1), hydrolyzate and/or partial condensate thereof is blended with (B) 10-80pts.wt. vinyl resin containing a silyl group containing a silicon atom bonded to hydrolyzable group and (C) 10-80pts.wt. organopolysiloxane containing a reactive functional group in such a way that the total amount of the components A-C is 100pts.wt. to give the aimed composition. Methylmethoxysilane is preferable as the composition A.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a coating composition, and more particularly, it relates to a coating composition that can be cured at low temperatures, has heat resistance, water resistance, boiling water resistance, and organic chemical resistance. The present invention relates to a coating composition suitable for providing a highly hard coating film with excellent properties such as water resistance, water permeability, alkali resistance, solvent resistance, weather resistance, stain resistance, smoothness, adhesion, and storage stability. .

[Conventional technology]

In recent years, it can be cured at low temperature, has heat resistance, water resistance,
Boiling water resistance, organic chemical resistance, water permeability resistance, alkali resistance,
There is a need for a coating composition that can form a highly hard coating film with excellent solvent resistance, weather resistance, stain resistance, smoothness, adhesion, storage stability, etc.

Coating compositions that meet some of these requirements include, for example, Japanese Patent Publication No. 52-39691, Japanese Patent Publication No. 53-5042, Japanese Patent Application Laid-Open No. 87736-1973, and Japanese Patent Application Publication No. 55-94971. , Japanese Patent Publication No. 56-992
Examples include compositions proposed in Japanese Patent Application Publication No. 36, Japanese Patent Application Laid-open No. 59-68377, and the like.

[Problem that the invention seeks to solve]

However, the coating compositions described in the above publications all contain organoalkoxysilane and colloidal silica or colloidal alumina as main components, and the resulting coatings have poor alkali resistance, heat resistance,
It has drawbacks such as poor water resistance, boiling water resistance, organic chemical resistance, water permeability resistance, solvent resistance, weather resistance, stain resistance, adhesion, and storage stability6, as well as insufficient smoothness of the coating film. have.

The present invention was made against the background of the above-mentioned conventional technical problems, and can be cured at low temperatures, has weather resistance, water permeability resistance,
Heat resistance, organic chemical resistance, solvent resistance, stain resistance, adhesion,
The purpose of the present invention is to provide a coating composition that has excellent storage stability and can form a hard, smooth coating film that is particularly excellent in alkali resistance, water resistance, and boiling water resistance.

Means for Solving Problem C] That is, the present invention provides (a) general formula Rn S t (OR' ) a, (wherein R is an organic group having 1 to 8 carbon atoms, and R' is an organic group having 1 to 8 carbon atoms; 1-5 alkyl group or C1-4 acyl group, n is O or 1); hydrolyzates and/or partial condensates of the alkoxysilanes (hereinafter referred to as " 10 to 80 parts by weight (referred to as "component (a)") in terms of alkoxysilane, a vinyl-based polymer having at least one silyl group in one polymer molecule that has a silicon atom bonded to a hydrolyzable group at the fbl end or side chain. 1.0 to 80 parts by weight of a resin (hereinafter referred to as "component (b)"), and (c) an organopolysiloxane having at least one reactive functional group in one molecule (hereinafter referred to as "component (c)") 10 to 80 parts by weight ((a) + (bl +
(c) = 100 parts by weight).

Next, the constituent elements of the composition of the present invention will be explained in detail.

(a) component (al component is (a)' general formula R,,S i(OR'
) a-,.

It is obtained by hydrolyzing and/or partially condensing an alkoxysilane represented by the above formula, Fuhai alkoxysilane.

R in such alkoxysilane is an organic group having 1 to 8 carbon atoms, such as an alkyl group such as a methyl group, an ethyl group, or a propyl group, as well as a γ-chloropropyl group, a vinyl group, etc. Lifluoropropyl group, γ-glycidoxypropyl group, T-methacryloxybrobyl group, γ
-mercaptofurovir group, phenyl group, 3,4-epoxycyclohexylethyl group, and the like.

Further, R' in the alkoxysilane 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, a propyl group, a butyl group, an acetyl group, and the like.

Further, n is an integer of O or 1, and when n is 0, it is, for example, tetraalkoxysilane, and when n is 1, it is, for example, monoalkyltrialkoxysilane.

Specific examples of these alkoxysilanes include tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, and tetrabutoxysilane; Condensates of tetraalkoxysilanes, methyltrimethoxysilane, methyltriethoxysilane,
Ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-
Chloropropyltriethoxysilane, vinyltrimethoxysilane, vinyl l-+J ethoxysilane, 3.3.3
-) Lifluoropropyltrimethoxysilane, 3.3.3
-1-lifluorobrobyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, T-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ- Organoalkoxysilanes such as mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, 3.4-epoxycyclohexylethyltrimethoxysilane, 3.4-epoxycyclohexylethyltriethoxysilane Among them, methyltrimethoxysilane, methyltriethoxysilane, and phenyltrimethoxysilane are preferred.

(The usage ratio of the al component in the composition is (a) +
Out of a total of 100 parts by weight of fbl+(c), the amount is 10 to 80 parts by weight, preferably 15 to 70 parts by weight in terms of alkoxysilane.If it is less than 10 parts by weight, the weather resistance and hardness of the resulting coating film may deteriorate. On the other hand, if it exceeds 80 parts by weight, the alkali resistance of the resulting coating film decreases.

Component (b) The component (b) used in the present invention is a polymer whose main chain is made of a vinyl polymer and which has a silyl group having a silicon atom bonded to a hydrolyzable group at the terminal or side chain. Most of the silyl groups contain at least one, preferably two or more, in the following general formula % (wherein X is a halogen atom, alkoxy group, acyloxy group, acyloxy group, phenoxy group , thioalkoxy group,
A hydrolyzable group such as an amino group, R1 is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an aralkyl group having 7 to 10 carbon atoms, m is an integer of 1 to 3).

Here, X is, for example, a halogen atom such as a chlorine atom or a bromine atom, an alkoxy group such as a methoxy group, an ethoxy group, a propoxy group, an acyloxy group such as an acetyl group or a propionyl group, a methylmercapto group, an ethylmercapto group, etc. A thioalkoxy group, and as R1, an alkyl group having 1 to 10 carbon atoms such as a methyl group, an ethyl group, a propyl group, an octyl group, a nonyl group, a benzyl group,
Examples include aralkyl groups having 7 to 1 carbon atoms such as phenethyl group and cumyl group.

Such a (bl component) may be produced by (i) reacting a hydrosilane compound with a vinyl resin having a carbon-carbon double bond, and may also be produced using the following general formula (where X% R', m is the same as above, and R2
For example, CH2=CH-1 CHz = CHCOO(cHz) x -1CHz =
It may be produced by polymerizing a silane compound represented by C(cH3)Coo (cHz')3-1, which is an organic group having a polymerizable double bond, and various vinyl compounds.

Here, the hydrosilane compounds used in the production method shown in (a) above include, for example, halogenated silanes such as methyldichlorosilane, trichlorosilane, and phenyldichlorosilane; methyljethoxysilane, methyldimethoxysilane , alkoxysilanes such as phenyldimethoxysilane, trimethoxysilane, and triethoxysilane; acyloxysilanes such as methyldiacetoxysilane, phenyldiacetoxysilane, and triacetoxysilane; methyldiaminoxysilane, triaminoxysilane, Examples include aminosilanes such as dimethylaminoxysilane and triaminosilane.

In addition, the vinyl resins used in the manufacturing method shown in (a) include, except for vinyl resins containing hydroxyl groups,
There is no particular limitation, for example, methyl (meth)acrylate, (
meth)ethyl acrylate, butyl (meth)acrylate,
(Meth) such as 2-ethylhexyl (meth)acrylate
Acrylic acid esters; Carboxylic acids such as (meth)acrylic acid, itaconic acid, and fumaric acid and acid anhydrides such as maleic anhydride; Epoxy compounds such as glycidyl (meth)acrylate; Diethylaminoethyl (meth)acrylate, aminoethyl vinyl ether, etc. Amino compounds; (meth)acrylamide, itaconic acid diamide,
α-ethylacrylamide, crotonamide, fumaric acid diamide, maleic acid diamide, N-butoxymethyl (
Amide compounds such as meth)acrylamide; acrylonitrile, styrene, α-methylstyrene, vinyl chloride,
Polymers of vinyl compounds selected from vinyl acetate, vinyl propionate, etc. are suitable.

During the production of polymers of these vinyl compounds, carbon-carbon double bonds for hydrosilylation reactions are created in vinyl resins by partially copolymerizing allyl acrylate, allyl methacrylate, diallyl phthalate, etc. It is possible to introduce

On the other hand, as the silane compound used in the production method shown in (b), for example, ・CH2= C, HS s
(OCH3)3, CH.

CHz ”CH3i Cj2z, CHz -CH3i
C1z, CH.

■ CHz ”CHCOO (cWz )z S i (O
CH3)2-CH2-CHCOO(cHz) w S
i (OCHi)x, CH2-CHCOO(cH2
) s S i C1s, CHz = C(cH3)Co
o (cHz)3 Si (OCH3)z, CHz
=C(cHi)Co0(cHz)xS1c1f
z, CH30, etc.

Furthermore, as the vinyl compound used in the production method shown in (b), it is possible to use the vinyl compound used in the polymerization of the vinyl resin in the production method (a) above. In addition to those described in the manufacturing method of (a), 2-hydroxyethyl (meth)acrylate, 2
Vinyl compounds containing hydroxyl groups such as -hydroxypropyl (meth)acrylate, 2-hydroxy vinyl ether, and N-methylol acrylamide can also be mentioned.

Specific examples of the component (b) used in the present invention as described above include Zemlac and Cyryl manufactured by Kanebuchi Chemical Industry ■; silicone acrylic varnish TSR1 manufactured by Toshiba Silicone ■;
71 etc.

The proportion of component (b) in the composition is (a) + (kll
+ (out of a total of 100 parts by weight of c1, the amount is 10 to 80 parts by weight, preferably 15 to ?0ffi parts; less than 10 parts by weight results in poor alkali resistance, while more than 80 parts by weight deteriorates weather resistance.

Component (c) Component (c) is an organopolysiloxane having at least one reactive functional group in one molecule.

As this component (c), for example, (c)' general formula R'
II S 10 (4-m) y□ (wherein R" represents an organic group having 1 to 8 carbon atoms, and a is 1.1 to 1.8), and organopolysiloxanes having one or more 10X' groups (where X' represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms) which are reactive functional groups bonded to a silicon atom. can.

R'' in the general formula (c)' is an organic group having 1 to 8 carbon atoms, such as an alkyl group such as a methyl group, an ethyl group, or a propyl group, as well as a γ-chloropropyl group, a vinyl group, or a 3,3-carbon group. .3-trifluoropropyl group, γ-glycidoxypropyl group, T-methacryloxypropyl group, T-
Examples include a mercaptopropyl group, a phenyl group, a 3,4-epoxycyclohexylethyl group, a T-aminopropyl group, and among these, a methyl group and a phenyl group are preferred.

In addition, (c)' general formula R"a S i Ou-m, /z
(7) a is 1.1-1.8, preferably 1.2-1.8
If it is less than 1.1, cracks may occur in the coating film of the composition;
If it exceeds this, the coating film may be difficult to cure.

Furthermore, the component (c) has one or more, preferably 3 to 30, reactive functional groups such as 10X' groups bonded to silicon atoms.

Here, X' of -〇X' group is a hydrogen atom or a carbon number 1
-5 alkyl groups, such as methyl, ethyl, propyl, butyl, and the like.

If a reactive functional group is not present in the component (c1), the curing reaction will not proceed sufficiently.

Specific examples of the above component (e) include silicone varnish TSR160 and TSR16 manufactured by Toshiba Silicone ■.
5, TSR3168;) - manufactured by Resilicone ■, silicone varnish 5H60/8, Ql-37; manufactured by Shin-Etsu Chemical ■, silicone intermediate KR211, KR-212, KR-
213, KR-214, KR-216, KR-218, and the like.

(The ratio of c1 component in the composition is (a) + (
b) + (c) in a total of 100 parts by weight, 10 to 80 parts by weight, preferably 15 to 70 parts by weight; if it is less than 10 parts by weight, the resulting coating film will have insufficient alkali resistance; If the amount exceeds 50%, the hardness of the resulting coating film will decrease.

In addition, the composition of the present invention has the above-mentioned (a)' general formula RnS
When using an alkoxysilane represented by i (OR' ) 4-fi, it is preferable to contain water.

In this case, the amount of water is 5t (OR') of the component (a)'.
).

In the case of a tetraalkoxysilane represented by: 2 times the mole or more of this tetraalkoxysilane, and in the case of an alkoxysilane where component (a)' is represented by R3i (OR'):+, 1 mole of this alkoxysilane .5 times the mole or more is appropriate.

This water is consumed by alkoxysilane condensation, but the proportion of water in the prepared composition should be 80 parts by weight or less per 100 parts by weight of component (a) in terms of alkoxysilane. Preferably, if it exceeds 80 parts by weight, the storage stability of the composition tends to decrease.

Furthermore, the composition of the present invention preferably contains a hydrophilic organic solvent.

This hydrophilic organic solvent mainly mixes components (a) to (c) uniformly, adjusts the concentration of components (a) to fc), and at the same time adjusts the solid content of the composition of the present invention. The present invention is intended to improve the dispersion stability and storage stability of the composition.

Examples of such hydrophilic organic solvents include alcohols such as methanol, ethanol, propyl alcohol, butyl alcohol, ethylene glycol, diethylene glycol, triethylene glycol, ethylene glycol monobutyl ether, and acetic acid ethylene glycol monoethyl ether, acetone, methyl ethyl ketone, and tetrahydrofuran. Examples include low-boiling hydrophilic organic solvents having a boiling point of 120°C or less.

Among these hydrophilic organic solvents, alcohols such as i-propyl alcohol, 5ec-butyl alcohol, n-propyl alcohol, n-butyl alcohol, diethylene glycol, ethylene glycol monobutyl ether, and acetic acid ethylene glycol monoethyl ether are preferable. , particularly preferred are i-propyl alcohol and acetic acid ethylene glycol monoethyl ether.

The composition of the present invention contains the above-mentioned components (a) to (c), and the total solid concentration thereof is preferably 10 to 50% by weight, particularly preferably 15 to 35% by weight, and 10 to 10% by weight. If it is less than % by weight, the solid content concentration is too low and the coating film formed by coating the resulting composition may not exhibit the properties such as heat resistance, water resistance, chemical resistance, and weather resistance. In addition, pinholes may occur in the coating film that is formed.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, and even if the composition is coated, it will not be uniform. In some cases, adverse effects such as difficulty in forming a coating film may occur.

In addition, it is also possible to add other fillers to the composition of the present invention as needed.

Such fillers are water-insoluble and include, for example, organic or inorganic pigments.

In addition, particulate or fibrous metals and alloys other than pigments, and their oxides, hydroxides, carbides, nitrides,
Sulfides, specific examples include particulate or fibrous iron,
copper, aluminum, nickel, silver, zinc, ferrite,
Carbon blank, stainless steel, silicon oxide, titanium oxide, aluminum oxide, chromium oxide, manganese oxide,
Examples include iron oxide, zirconium oxide, cobalt oxide, synthetic mullite, zircon (zirconium silicate), aluminum hydroxide, iron hydroxide, silicon carbide, silicon nitride, boron nitride, and molybdenum disulfide.

The average particle size or average length of these fillers is usually 0
．． 05 to 50 μm, preferably 0.1 to 5 μm,
If it is less than 0.605 μm, the viscosity of the composition may increase or the desired film thickness may not be achieved, while if it exceeds 50 μm, the dispersibility of the resulting composition tends to deteriorate.

The proportion of fillers used if necessary in the composition is +
Usually 5 to 500 parts by weight, preferably 10 to 300 parts by weight of component a) per 100 parts by weight in terms of alkoxysilane.
If the amount is less than 5 parts by weight, the performance imparted by the filler to the composition cannot be fully exhibited;
If the amount exceeds 0 parts by weight, the resulting composition may gel, and the hardness of the coating film obtained by coating will deteriorate, as well as the adhesion to the substrate.

Incidentally, the filler to be used as necessary is selected depending on the purpose of the coating film to be obtained, for example, based on the following selection.

■Silicon oxide, titanium oxide, aluminum oxide, chromium oxide, zirconium oxide, synthetic mullite, zircon, silicon carbide, silicon nitride, etc. are used as fillers for making corrosion-resistant films.

■As a filler for making an electrically insulating film, use electrically insulating metal oxides, carbides, or nitrides that do not contain alkali metals.

■Oxides such as iron oxide, titanium oxide, cobalt oxide, zinc oxide, tin oxide, lead oxide, and aluminum oxide are used as fillers to create the decorative film.

■Oxides such as iron oxide, copper oxide, cobalt oxide, manganese oxide, chromium oxide, silicon oxide, titanium oxide, aluminum oxide, and zircon are used as fillers for making the heat radiation film.

■As fillers for making conductive or semiconductive films,
copper, aluminum, nickel, silver, carbon black,
Use tin oxide, etc.

■Metal oxides, hydroxides, nitrides, etc. with low thermal conductivity are used as fillers to create the heat insulating film.

■Zinc, lead, chromium, etc. are used as fillers to create the anti-rust film.

(2) In addition, two or more of the above-mentioned fillers can be used in combination in order to create a coating film that takes advantage of the characteristics of various fillers.

Further, in order to cure the composition of the present invention more rapidly, a curing accelerator may be used, and in order to cure the composition at a relatively low temperature, it is more effective to use a curing accelerator in combination.

Such curing accelerators include alkaline compounds such as sodium hydroxide and potassium hydroxide; alkyl titanic acids,
Acidic compounds such as phosphoric acid, p-toluenesulfonic acid, and phthalic acid; curing of ethylenediamine, hexanediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, piperidine, piperazine, metaphenylenediamine, ethanolamines, triethylamine, and epoxy resins Amine compounds such as various modified amines used as agents; γ-aminopropyltriethoxysilane, γ-(2-aminoethyl)-aminopropyltrimethoxysilane, r-(2-aminoethyl)-aminopropylmethyldimethoxysilane , T-anilinopropyltrimethoxysilane and other amine-based silane coupling agents; (c4H9)Z Sn (OCOC++H
zz) z, (ca H9) z S n (OCOCH
= CHCOOCH:l ) z, (c4H9)2S
n (S CHt Coo), (c4HJz S
n (S CHz COOCa Hlt)
Organotin compounds such as z, (c4H9')-3n=S; (c4Hq)25nO1(cs H+t)zS n
O-.

(c, Hq) SnOl (cB Hlt) sn.

Reaction products of organic tin oxides such as ethyl silicate, ethyl silicate 40, dimethyl maleate, diethyl maleate, dioctyl phthalate; triisopropoxyaluminum, tri5e
Metal alkoxides such as c-butoxyaluminum and tetrabutoxyzirconium; chelates of metal alkoxides such as aluminum and zirconium and chelates such as acetylacetone and ethylacetoacetate are used.

The proportion of these curing accelerators in the composition is usually 50 parts by weight or less, preferably 30 parts by weight or less, based on 100 parts by weight of the solid content of the composition of the present invention.

The composition of the present invention includes various surfactants, silane cuff pulling agents other than those mentioned above, titanium coupling agents, and alkali metal salts such as naphthenic acid, octylic acid, nitrous acid, sulfite, aluminic acid, and carbonic acid. Additives such as dyes can also be added.

Furthermore, the composition of the present invention may contain an organic solvent other than the above-mentioned hydrophilic organic solvent, and such an organic solvent may be any solvent that does not cause precipitation of the above-mentioned +a) to (c) components. Any substance may be used, including aliphatic hydrocarbons, aromatic hydrocarbons, halogenated hydrocarbons, ketones, esters, ethers, ketone ethers, and ketone esters used in general paints, coatings, etc. and ester ethers.

These organic solvents are usually used in an amount of about 300 parts by weight or less based on 100 parts by weight of the solid content of the composition of the present invention.

The composition of the present invention containing components fa) to (c) as described above can be prepared by, for example, first containing (a)'alkoxysilane, which is the starting material for component (a), component (b), and component (c). The components, water and a hydrophilic organic solvent are mixed to perform hydrolysis and condensation.

Here, (in the listening step, the components (a) to (c), and if necessary, water and a hydrophilic organic solvent are mixed and stirred at a temperature of 10 to 70 °C, preferably 20 to 60 °C. ℃
, for a period of 1 to 10 hours, preferably 2 to 8 hours.

Next, (b) it is further diluted with the hydrophilic organic solvent to a predetermined solid content concentration, if necessary.

Furthermore, (c) the curing accelerator is added as necessary before coating.

In addition, in the method for producing the composition of the present invention containing components (a) to (c), when blending the filler etc., the components (a)' to (c) and the filler are mixed. Then, the above-mentioned (inquiry step) is carried out, followed by (b) step, and then (c) step. Alternatively, a filler may be added separately in (b) step after the (inquiry step) is completed.

The composition of the present invention can be applied to the surface of the target substrate by a coating method such as brushing, spraying, or day nobbing, to a thickness of about 5 to 50 μm in one coat, and to a thickness of 10 μm in two to three coats.
A coating film of ~150 μm can be formed at room temperature ~
It is possible to form a hard coating film by leaving it at a temperature of about 300° C. for about 10 minutes to about 12 hours and drying it.

Examples of substrates to be coated with the composition of the present invention include stainless steel, aluminum, ceramics, cement, paper, glass, and plastic.

〔Example〕

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples.

In the examples, parts and percentages are based on weight unless otherwise specified.

Moreover, various evaluations in Examples were conducted according to the following test methods.

(2) Storage stability was determined by storing the sample in a polyethylene bottle tightly sealed without adding a curing accelerator, visually determining the presence or absence of gelation, and measuring the time it took for gelation to occur.

(2) Water resistance was determined by immersing the film in tap water at room temperature for 60 days and observing the state of the coating film.

■ Boiling water resistance was determined by boiling in tap water for 8 hours and observing the state of the coating film.

■Hardness was based on pencil hardness according to JIS K5400.

■Weather resistance is determined by Jl, S K5400.
A 2,000 hour irradiation test was conducted using a meter, and the state of the coating film was observed.

(2) Chemical resistance was determined by adding one drop of a 5% aqueous sodium hydroxide solution onto the coating film, allowing it to stand for one day in a petri dish with a lid, washing with water, and observing the condition of the coating film.

■Pot life is determined by adding a hardening accelerator in a polyethylene bottle, storing it in a tightly capped container, and visually determining the presence or absence of gelation.
The time for gel formation was measured.

Note that the criteria measured by the above test method were based on the following symbols.

O: No abnormality at all.

△: Peeling, rust formation, corrosion, etc. were observed in some parts.

x: Peeling, rust formation, corrosion, etc. were observed in most or all of the samples.

Example 1 Into a reactor equipped with a reflux condenser and a stirrer, (a) 65 parts of 299 ml of main methyltrimeth, 65 parts of (solid content concentration;
0%, solvent: xylene, Kanebuchi Kogyo ■, Zemlac) 5
5 parts, 30 parts of component (c) (manufactured by Toshiba Silicone ■, silicone varnish TSR3168) was dissolved in 100 parts of i-propyl alcohol, and then 140 parts of i-propyl alcohol and 10 parts of water were added, and the mixture was heated to room temperature. The mixture was reacted for 2 hours to obtain coating composition (2) shown in Table 1.

By the same operation as above, coating compositions ■ to [Co., Ltd. ] was obtained.

Furthermore, 80 parts of zirconium silicate and 3 parts of titanium dioxide were added to 400 parts of coating composition (1) to create a coating composition! I1FO was obtained.

Comparative Example 1 In the same manner as in Example 1, a coating composition @~0 having the composition shown in Table 1 was obtained.

Test Example 1 Coating composition ~ [phase] obtained in Example 1 and coating composition @~ obtained in Comparative Example 1
[Phase] was coated with or without the addition of various curing accelerators shown in Table 2 to the following test pieces A to C using an air spray gun to give a dry film thickness of 10 μm. A cured coating film was formed at a temperature of room temperature to 150°C.

Test piece A: Slate board (JSRA test piece C
Test piece A was coated with coating composition (4) in a dry film thickness of 40 μm, and heat-treated at 150° C. for 30 minutes.

Test piece C: An inorganic coating composition (manufactured by Nippon Gosei Gomu, Glass Riki EIIOI) was applied to test piece A in the same manner as test piece B, and then heated and dried.

The results for these cured coatings are shown in Table 2.

Test Example 2 A coating film was formed in the same manner as in Test Example 1, except that the test piece was replaced with the test piece D-F below.

Test piece D: Aluminum plate (JISH4000S
A1050P) Test piece E: Coating composition (1) was applied to test piece D to a dry film thickness of 40 μm and dried by heating at 150° C. for 30 minutes.

Test piece F: A non-IT coating composition (manufactured by Japan Synthetic Rubber ■, Glass Power EIIOI) was applied to test piece D in the same manner as test piece E, and then dried by heating.

The results for these cured coatings are shown in Table 3.

〔Effect of the invention〕

The coating composition of the present invention comprises component (a), ('b
A composition containing three components: component ) and component +C),
It has excellent storage stability, can be cured at low temperatures, and the resulting coating film can significantly improve alkali resistance in particular. Moreover, the coating film obtained from the composition of the present invention has high hardness, a smooth appearance, and excellent weather resistance, water resistance, boiling water resistance, heat resistance, water permeability resistance, and organic chemical resistance. , solvent resistance, stain resistance, and excellent adhesion to substrates.

Furthermore, if a filler is added as necessary, it is possible to obtain a coating film with various functions depending on the type of filler.

Patent applicant: Japan Synthetic Rubber Co., Ltd. Agent: Patent Attorney Takashi Shirai

Claims (2)

[Claims] (1) (a) General formula R_nSi(OR')_4_-_n
(In the formula, R is an organic group having 1 to 8 carbon atoms, and R' is an organic group having 1 to 8 carbon atoms.
5 alkyl group or an acyl group having 1 to 4 carbon atoms,
an alkoxysilane represented by n is 0 or 1),
10 to 80 parts by weight of the hydrolyzate and/or partial condensate of the alkoxysilane in terms of alkoxysilane; (b) polymer 1 containing a silyl group having a silicon atom bonded to a hydrolyzable group at the terminal or side chain; 10 to 80 parts by weight of a vinyl resin having at least one in the molecule, and (c) 10 to 80 parts by weight of an organopolysiloxane having at least one reactive functional group in one molecule (however,
(a)+(b)+(c)=100 parts by weight). (2) The component (c) has the general formula R″_aSiO_(_4_
-_a_)_/_2 (in the formula, R'' represents an organic group having 1 to 8 carbon atoms, and a is 1.1 to 1.8), and has a silicon atom A coating composition according to claim 1, which is an organopolysiloxane having attached reactive functional groups.