JPH0525423A - Coated article - Google Patents

Abstract

PURPOSE:To provide an article coated with a nonaq. coating compsn. which has a good storage stability and adheres well to the article. CONSTITUTION:An article is coated with a nonaq. coating compsn. contg. a hydrolyzable ester compd. and (or) an alkyl alcohol, and a silylated vinyl resin which has a main chain consisting substantially of a vinylic polymer, at least one silicon group bonded to a hydrolyzable group at the molecular end or in the side chain, and 0.1-20% structural units derived from a comonomer component comprising a carboxamide having a polymerizable group and is prepd. from a monomer mixture consisting mainly of an acrylic ester and (or) a methacrylic ester.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention comprises a vinyl resin containing a hydrolyzable silyl group and having a (meth) acrylic acid ester as a main component, a hydrolyzable ester compound and / or an alkyl alcohol. The present invention relates to a coated article coated with a non-aqueous coating composition, and particularly to a coated article coated with a non-aqueous coating composition having excellent storage stability and having a cross-linking curability and having good adhesion.

[0002]

2. Description of the Related Art Various compounds containing a silyl group bonded to a hydrolyzable group as shown in the present invention are known, and the hydrolyzable silyl group provides good adhesion to an inorganic substance. It is widely used as a paint, a coating agent, an adhesive, a sealant, a silane coupling agent, etc. because it crosslinks at room temperature by water and moisture, especially moisture in the air to form a cured product with excellent durability.

However, such a compound tends to react with a trace amount of water in the storage system during storage and gradually thicken, which causes inconvenience in the above-mentioned applications.

Therefore, although such a compound is stored and used in a state in which water contamination is suppressed as much as possible, nevertheless, when repeatedly used, moisture content in the air is mixed, and further, a pigment and a filler are blended. In this case, it is unavoidable to mix in the water contained in these compounds or adsorbed on the surface.

For this reason, improvement of storage stability has become a serious problem in practical use.

Further, when the compound contains a hydroxyl group, a carboxylic acid group, an amide group and the like and contains an active hydrogen group, the physical properties such as adhesion can be expected to be improved, but US Pat. No. 4,043,
The 953 specification shows that it contains a hydroxyl group, a carboxylic acid group, an amide group, etc., and if it contains an active hydrogen group, the storage stability is particularly poor, and that it thickens and gels early during storage. There is.

[0007]

However, surprisingly, the present inventors have found that a vinyl group having a hydrolyzable silyl group containing 0.1 to 20% by weight of a carboxylic acid amide having a polymerizable group as a copolymerization component. The resin has very good storage stability, and the hydrolyzable ester compound and / or
The present inventors have found that the addition of alkyl alcohol further improves the storage stability, and that a coated article coated with such a composition has good adhesion as expected, and has reached the present invention.

That is, according to the present invention, the main chain is substantially composed of a vinyl polymer, and at least one silicon group bonded to a hydrolyzable group is present in one molecule in the side chain or at the end of the molecule. A silyl group-containing vinyl resin containing carboxylic acid amide having a polymerizable group as a polymerization component in an amount of 0.1 to 20% (% by weight, the same shall apply hereinafter) and containing an acrylic acid ester and / or a methacrylic acid ester as a main component. The present invention relates to a coated article coated with a non-aqueous paint containing a decomposable ester compound and / or an alkyl alcohol.

[0009]

EXAMPLE A silyl group-containing vinyl resin used in the present invention contains at least one, preferably two or more silyl groups bonded to one molecule in one molecule, and is further polymerizable as a copolymerization component. Carboxylic acid amide having a group of 0.1
-20%, and most of the silyl groups have the general formula:

[0010]

[Chemical 1]

(In the formula, X is a hydrolyzable group, R ₁ and R ₂ are hydrogen or an alkyl group having 1 to 10 carbon atoms, an aryl group or an aralkyl group, and n is an integer of 1, 2 or 3. ).

The silyl group-containing vinyl resin used in the present invention can be produced by various methods, but it is (A) a vinyl resin having a carbon-carbon double bond at its side chain or molecular end and hydrosilane. The method using a hydrosilylation reaction and the method using (B) a copolymer of a vinyl compound and a silyl compound having a polymerizable double bond are industrially effective methods.

The details will be described below.

(A) The silyl group-containing vinyl resin used in the present invention can be easily produced by reacting a hydrosilane compound with a vinyl resin having a carbon-carbon double bond in the presence of a Group VIII transition metal catalyst. To be done.

The hydrosilane compound used in the above method (A) has a general formula:

[0016]

[Chemical 2]

(Wherein R ₁ is a monovalent hydrocarbon group selected from an alkyl group having 1 to 10 carbon atoms, an aryl group and an aralkyl group, X is a halogen atom, an alkoxy group, an acyloxy group, an aminoxy group and a phenoxy group. , A thioalkoxy group,
A group selected from an amino group and n is an integer of 1 to 5).

Specific examples of the hydrosilane compound represented by this general formula are halogenated silanes such as methyldichlorosilane, trichlorosilane and phenyldichlorosilane; methyldiethoxysilane, methyldimethoxysilane, phenyldimethoxysilane, Alkoxysilanes such as trimethoxysilane and triethoxysilane; Acyloxysilanes such as methyldiacetoxysilane, phenyldiacetoxysilane and triacetoxysilane; Methyldiaminoxysilane, triaminoxysilane, methyldiaminosilane, triaminosilane, etc. The various silanes are listed.

The amount of the hydrosilane compound used can be any amount with respect to the carbon-carbon double bond contained in the vinyl resin, but it is preferably 0.5 to 2 times the molar amount. It does not prevent the use of higher amounts of silane, but is only recovered as unreacted hydrosilane.

Further, in the method (A), a highly reactive halogenated silane can be easily used as a hydrosilane compound with an inexpensive basic raw material. The silyl group-containing vinyl resin obtained by using halogenated silanes cures rapidly at room temperature while generating hydrogen halide when exposed to air, but irritating odor due to hydrogen halide and corrosion of the coated substrate However, it can be practically used only in limited applications. Therefore, it is desirable to further convert the halogen functional group to another hydrolyzable functional group.

The vinyl resin used in the method (A) contains a carboxylic acid amide having a polymerizable group as a component, and contains methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate. ,
Resins containing acrylates such as butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, and methacrylates as the main components are suitable. However, acrylic acid, methacrylic acid, itaconic acid, carboxylic acids such as fumaric acid and acid anhydrides such as maleic anhydride, glycidyl acrylate, epoxy compounds such as glycidyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, aminoethyl vinyl ether, etc. A copolymerization component containing a carboxylic acid group, an acid anhydride group, an epoxy group, an amino group, etc., such as an amino compound, brings about an improvement in adhesiveness but has a bad influence on storage stability.
-5% is preferable.

During the production of a homopolymer or a copolymer of these vinyl compounds, radical copolymerization of allyl acrylate, allyl methacrylate, diallyl phthalate, etc. is carried out to obtain a carbon-carbon for hydrosilylation reaction in the vinyl resin. It is possible to introduce a carbon double bond. The amount of the monomer used for this purpose can be arbitrarily determined according to the number of silyl groups in the intended resin. further,
A chain transfer agent such as n-dodecyl mercaptan or t-dodecyl mercaptan may be added as necessary to obtain a silyl group-containing vinyl resin having a molecular weight suitable for the purpose of use. A solvent may or may not be used in the polymerization of these vinyl compounds, but when used,
The use of non-reactive solvents such as ethers, hydrocarbons, acetates is preferred.

Examples of the carboxylic acid amide having a polymerizable group used in the method (A) include acrylamide, methacrylamide, itaconic acid diamide, α-ethyl acrylamide, crotonamide, fumaric acid diamide, maleic acid diamide and N-methylol acrylamide. And so on,
0.1 to 20% in vinyl resin containing silyl group, preferably
It is recommended to contain 0.5-10%.

In the method (A), a transition metal complex catalyst is required at the stage of reacting the hydrosilane compound with the carbon-carbon double bond remaining on the side chain of the copolymer or the terminal of the copolymer.

As the transition metal complex catalyst, a Group VIII transition metal complex compound selected from platinum, rhodium, cobalt, palladium and nickel is effectively used.

The hydrosilylation reaction is accomplished at any temperature of 50 to 150 ° C., and the reaction time is about 1 to 10 hours.

(B) Another method for producing the silyl group-containing vinyl resin used in the present invention is represented by the general formula:

[0028]

[Chemical 3]

(In the formula, R ₁ is a monovalent hydrocarbon group selected from an alkyl group having 1 to 10 carbon atoms, an aryl group and an aralkyl group, R ₂ is an organic residue having a polymerizable double bond, and X is A halogen atom, an alkoxy group, an acyloxy group, an aminoxy group, a phenoxy group, a thioalkoxy group, a group selected from an amino group, n is an integer of 1, 2 or 3) and various vinyl compounds. It is a method of radical polymerization.

The silane compound used in the method (B) is, for example,

[0031]

[Chemical 4]

And the like.

These silane compounds can be synthesized by various methods. For example, acetylene, allyl acrylate, allyl methacrylate, diallyl phthalate, methyldimethoxysilane, methyldichlorosilane, trimethoxysilane and trichlorosilane can be synthesized from group VIII. It can be produced by reacting in the presence of a transition metal catalyst.

As the vinyl compound used in the method (B), it is possible to use the compound used at the time of synthesizing the vinyl resin in the method (A), but the compounds described in the method (A). Besides 2-hydroxyethyl acrylate, 2-
A vinyl compound having a hydroxyl group such as hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 2-hydroxyvinyl ether, N-methylol acrylamide, Aronix 5700 (produced by Toagosei Co., Ltd.) is also possible. However, as in the method (A), the copolymerization component containing a carboxylic acid group, an acid anhydride group, an epoxy group, an amino group and a hydroxyl group is 0 to
It is preferably 5%.

The copolymer of the vinyl compound and the silane compound is synthesized by a usual solution polymerization method. Vinyl compound, silane compound, radical initiator, n-dodecyl mercaptan, t-, which is optionally used to obtain a silyl group-containing copolymer having a molecular weight according to the purpose of use
Add a chain transfer agent such as dodecyl mercaptan,
React at ~ 150 ° C. The solvent may or may not be used, but when used, it is preferable to use a non-reactive solvent such as ethers, hydrocarbons and acetic acid esters.

The silyl group-containing vinyl resin thus obtained can mutually convert a hydrolyzable group into another hydrolyzable group by a known method.

In this way, the main chain is composed essentially of a vinyl polymer, and at least one silicosilicon group bonded to a hydrolyzable group is contained in one molecule. A carboxylic acid amide having a functional group of 0.1 to
A silyl group-containing vinyl resin containing 20% is obtained. The resin has excellent storage stability and shows excellent curability with or without the use of a curing accelerator.

The silyl group-containing vinyl resin used in the present invention is not particularly limited as long as it contains a carboxylic acid amide having a polymerizable group as a copolymerization component, but it is particularly storage-stable, for example, a silyl group-containing vinyl resin. If the silyl group content per resin molecule is high, or if a pigment containing a large amount of water such as transparent iron oxide is dispersed to enamell, etc., the storage stability will be high if the molecular weight of the resin is high. Therefore, a molecular weight of 1,000 to 30,000 (number average molecular weight by GPC) is preferable.

Further, in the non-aqueous coating composition containing the silyl group-containing vinyl resin used in the present invention, the hydrolyzable ester compound used for improving the storage stability is trimethyl orthoformate, triethyl orthoformate, Trialkyl orthoformates such as tripropyl orthoformate and tributyl orthoformate, and the general formula: R
_(4-n) SiX _n (wherein X is a hydrolyzable group and R is 1
The valent organic group may or may not include a functional group. n is an integer of 1 to 4, preferably 3 or 4), and a hydrolyzable organosilicon compound represented by the formula: methyltriethoxysilane, ethyltriethoxysilane,
Phenyltriethoxysilane, methyltriacetoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, tetramethyl orthosilicate, ethyl silicate, tetrapropyl orthosilicate, tetrabutyl orthosilicate, etc. used. The hydrolyzable ester compound is used in an amount of preferably 0.1 to 50 parts, more preferably 0.2 to 30 parts, based on 100 parts by weight of the silyl group-containing vinyl resin (parts by weight, hereinafter the same).

In the non-aqueous paint used in the present invention, the alkyl alcohol used for improving the storage stability is preferably an alcohol having an alkyl group having 1 to 10 carbon atoms, such as methyl alcohol, ethyl alcohol and propyl. Alcohol, isopropyl alcohol, butyl alcohol, isobutyl alcohol, sec-butyl alcohol, tert-butyl alcohol, n-amyl alcohol, isoamyl alcohol, hexyl alcohol, octyl alcohol, cellosolve and the like are used. The alkyl alcohol is preferably used in the range of 0.1 to 50 parts with respect to 100 parts of the silyl group-containing vinyl resin.

The non-aqueous paint containing the silyl group-containing vinyl resin, the hydrolyzable ester compound and / or the alkyl alcohol used in the present invention reacts with a slight amount of water at room temperature when exposed to the atmosphere. It forms a network and hardens. In this case, the curing rate changes depending on the atmospheric temperature, the relative humidity and the type of hydrolyzable group, and therefore the type of hydrolyzable group needs to be fully considered before use.

In curing the non-aqueous paint used in the present invention, a curing accelerator may or may not be used. When using a curing accelerator, a metal salt of a carboxylic acid such as alkyl titanate, tin octylate, dibutyltin dilaurate and lead octylate, or a sulfide type or mercaptide type such as monobutyltin sulfide or dioctyltin dioctylmercaptide. Organic tin compounds, acidic catalysts such as phosphoric acid, p-toluenesulfonic acid, phthalic acid, tetraethylenepentamine, triethylenediamine, amines such as N-β-aminoethyl-γ-aminopropyltrimethoxysilane, potassium hydroxide Alkaline catalysts such as sodium hydroxide are effective. The addition amount of these curing accelerators is 0.00 with respect to the resin.
It is preferably from 1 to 10%.

Since the non-aqueous paint used in the present invention can be cured at room temperature or low temperature, for example, as shown in the examples, it can be rapidly cured at room temperature to form an excellent coating film having very high surface gloss. To give a coated product.

By adding a compound capable of co-condensing with the silyl group-containing vinyl resin such as ethyl silicate to the non-aqueous coating material, it is possible to improve the physical properties of the coating film such as very high surface hardness. . Further, it is possible to blend the non-aqueous paints with various resins currently used as paints and coating agents, for example, lacquer paints, acrylic lacquer paints, thermosetting acrylic paints, alkyd paints, melamine. To obtain a coated product that can be used by mixing with paints, epoxy-based paints, etc. in an appropriate ratio, and that has improved physical properties such as adhesion of these paints and coating agents to substrates, and weather resistance of coating films. You can

Various fillers and pigments can be mixed in the non-aqueous paint used in the present invention. As the filler and pigment, various kinds of silica, calcium carbonate, magnesium carbonate, titanium oxide, iron oxide, glass fiber and the like can be used. Therefore, the non-aqueous paint is also useful as a coating composition for aircraft, buildings, automobiles, glass and the like.

The silyl group-containing vinyl resin composition used in the present invention is useful as a sealing composition and a surface treatment agent for various inorganic substances, and is excellent in adhesiveness to inorganic substances and organic substances. It is also useful as an adhesiveness improver for these adhesives by blending them with an inorganic substance, an organic substance-organic substance, in particular an inorganic substance-organic substance adhesive, or another adhesive.

Next, the method of the present invention will be specifically described based on Examples.

Example 1 30 g of styrene was added to 90 g of xylene solvent heated to 90.degree.
g, allyl methacrylate 19g, methyl methacrylate 20
g, n-butyl methacrylate 19 g, n-butyl acrylate 14 g, maleic anhydride 2 g, acrylamide 4 g, n
-A solution of 2 g of azobisisobutyronitrile dissolved in 2 g of dodecyl mercaptan and 10 g of n-butanol was added dropwise and reacted for 10 hours to obtain a vinyl polymer having a molecular weight of 8,000 and containing an allyl type unsaturated group.

The infrared absorption spectrum of this product was 1648 cm.
^An absorption due to a carbon-carbon double bond at ^-1 and an absorption of an acid anhydride at 1780 cm ^-1 were observed.

40 g of the solvent was removed from the obtained polymer solution under reduced pressure, and most of n-butanol was removed.

A solution of 1.5 g of methyldimethoxysilane and 0.0005 g of chloroplatinic acid in isopropanol was added to 16 g of the obtained allyl-type unsaturated group-containing vinyl copolymer solution, and the mixture was allowed to react at 90 ° C. for 6 hours under sealing. In the infrared absorption spectrum of this product, the absorption at 1648 cm ^-1 disappeared, and a silyl group-containing vinyl polymer was obtained.

Example 2 30 g of styrene and C in 70 g of xylene heated to 90 ° C.
_{H 2 = C (CH 3)} COO (CH 3) 3 Si (OC
H ₃ ) ₃ 22 g, methyl methacrylate 22 g, n-butyl methacrylate 15 g, n-butyl acrylate 18 g, acrylamide 4 g, and acetone 10 g were added dropwise with a solution of 2 g of azobisisobutyronitrile and reacted for 10 hours. A silyl group-containing vinyl polymer having a molecular weight of 14,000 (molecular weight measurement method: GPC method) was obtained.

Example 3 50 g of styrene and C in 70 g of xylene heated to 90 ° C.
_{H 2 = C (CH 3)} COO (CH 2) 3 Si (OC
H ₃ ) ₃ 22 g, methyl methacrylate 22 g, n-butyl methacrylate 15 g, n-butyl acrylate 18 g, acrylamide 4 g, acetone 10 g, n-dodecyl mercaptan 2 g, a solution of azobisisobutyronitrile 2 g dissolved therein is added dropwise. Then, the reaction was carried out for 10 hours to obtain a silyl group-containing vinyl polymer having a molecular weight of 9,000.

Example 4 In place of 2 g of n-dodecyl mercaptan of Example 3, n-
The same reaction was carried out using 4 g of dodecyl mercaptan to obtain a silyl group-containing vinyl resin having a molecular weight of 6,000.

Example 5 8 g of acrylamide was used instead of 4 g of acrylamide of Example 4, and the same reaction was carried out to obtain a silyl group-containing vinyl resin.

Example 6 In the same manner as in Example 3, except that 2 g of n-dodecyl mercaptan and 4 g of acrylamide were used, 6 g of n-dodecyl mercaptan, 4 g of acrylamide and 2 g of maleic anhydride were used to carry out the same reaction, and a silyl group-containing vinyl having a molecular weight of 5,000 was used. I got a system resin.

Example 7 The same reaction was carried out using 4 g of N-methylol acrylamide instead of 4 g of acrylamide of Example 4,
A silyl group-containing vinyl resin was obtained.

Comparative Example 1 A silyl group-containing vinyl resin having a molecular weight of 6,000 was obtained in the same manner as in Example 4 except that 26 g of methyl methacrylate was added instead of 4 g of acrylamide.

Comparative Example 2 A silyl group-containing resin was obtained in the same manner as in Example 4, except that the amount of methyl methacrylate (22 g) and acrylamide (4 g) used in Example 4 were changed to 24 g of methyl methacrylate and 2 g of acrylic acid.

Comparative Example 3 The same operation as in Example 3 was carried out except that 4 g of acrylamide was replaced with 4 g of hydroxyethyl methacrylate and the temperature of xylene was changed to 110 ° C. The resin obtained has a viscosity of 6,500.
Since it was extremely high and was unsuitable as a paint from the viewpoints of handleability and workability, a storage stability test was not conducted.

White enamel was synthesized by mixing the polymer solutions obtained in Examples 1 to 7 and Comparative Examples 1 and 2 described above with titanium oxide as a white pigment in a ball mill so that the solid content ratio was 1: 1. Then, the stabilizer shown in Table 1 was added and diluted with a solvent (xylene) to an appropriate viscosity, and these diluted white enamel were sealed at 50 ° C for 1
It was stored for a month, and the change in viscosity before and after storage was measured. The results are shown in Table 1.

No pigment was added to the polymer solutions obtained in Examples 1 to 6, the stabilizers shown in Table 1 were added, and 6000 ppm of water was added to the mixed solution. ℃,
A one-month storage test was performed to measure the change in viscosity before and after storage. Further, for comparison, the change in viscosity was measured under the same conditions except that no stabilizer was added, and the results are shown in Table 1.

Further, 3 parts by weight of dioctyl tin dimaleate as a curing catalyst was added to 100 parts of the resin, as a curing catalyst.
The coating film obtained by overcoating on the nitrocellulose-based lacquer surfacer coating film coated on a mild steel plate was heat-treated at 60 ° C. for 40 minutes, and one day later, a goggles test (JIS K 5400) was performed. The results are shown in Table 1.

[0064]

[Table 1]

As is clear from Table 1, when the stabilizer used in the present invention was added to a silyl group-containing vinyl resin copolymerized with a carboxylic acid amide, which is considered to have poor storage stability, the conventional method was used. It can be seen that storage stability equivalent to that obtained when a stabilizer is added to a silyl group-containing vinyl resin that does not contain a polar group, which is said to be stable, can be obtained. Even after long-term storage, the viscosity is the same as before storage, and painting work can be performed easily even after long-term storage.

In addition, among the above white enamel, Example 4
In addition to the polymer obtained in Comparative Example 1 and 3 parts of dioctyltin dimaleate as a curing catalyst per 100 parts of resin, it is overcoated on a nitrocellulose-based lacquer surfacer coating film coated on a mild steel plate. The coated film at 60 ℃ 40
After heat treatment for 1 minute, a solvent resistance test (spot test) was performed 1 day later. The results are shown in Table 2.

As an evaluation method, one drop of toluene or thinner for lacquer was dropped on the surface of the coating film, and the presence or absence of abnormality of the coating film was examined according to the following criteria.

◯ indicates no change. △ changes slightly. × indicates swelling or peeling.

[0069]

[Table 2]

It can be seen from Table 2 that the coating film of the coating material of the present invention has excellent adhesion to the substrate.

[0071]

The coated article of the present invention is a coated article coated with a non-aqueous paint having good storage stability and has a coating film with good adhesion.

Claims (1)

What is claimed is: 1. A main chain is substantially composed of a vinyl polymer, and at least one silicon group bonded to a hydrolyzable group is present in one molecule in a side chain or a molecular end, and further, a copolymerization component. As a silyl group-containing vinyl resin containing 0.1 to 20% by weight of a carboxylic acid amide having a polymerizable group as a main component, an acrylic acid ester and / or a methacrylic acid ester as a main component,
A coated article coated with a non-aqueous paint containing a hydrolyzable ester compound and / or an alkyl alcohol.