JP2875810B2 - Stabilized coating composition - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a coating composition containing a resin obtained by copolymerizing a vinyl monomer having an alkoxysilyl group and having excellent storage stability. Things.

[Related Art] A resin obtained by copolymerizing a monomer having an alkoxysilyl group has a property of being crosslinked at normal temperature by moisture, particularly moisture in the atmosphere, and is therefore useful as a cold-setting coating.

However, such properties are problematic in terms of the stability of the paint, and during storage, they tend to react with water in the system and gradually increase in viscosity. Therefore, it has been proposed to add an orthoformate or an orthoacetate and, if necessary, an alkyl alcohol to the coating composition in order to maintain the storage stability (Japanese Patent Application Laid-Open No. 60-47076). .

[Problems to be Solved by the Invention] However, it is difficult to obtain satisfactory storage stability by the conventional techniques, and the applicant has taken such measures as an orthopropionate and / or an orthobutyrate and an alkyl instead of the ester. A coating composition using a combination of alcohols (Japanese Patent Application No. 63-13333) was previously filed. However, according to the study of the present inventors, the coating composition containing the alkoxysilyl group-containing copolymer resin has a great influence on the stability of the system also the presence of a pigment, increases the viscosity of the viscosity over time, In particular, it has been found that this tendency is remarkable when a copper phthalocyanine pigment widely used as a blue pigment is used.

Since the blending of the pigment in the paint composition is an indispensable condition,
In order to make the coating composition containing the alkoxysilyl group-containing copolymer resin more practical, such a problem must be solved.

[Means for Solving the Problems] Accordingly, the present inventor has conducted intensive studies in order to solve such problems, and as a result, a carboxylic acid monomer is further copolymerized as a copolymer component into the alkoxysilyl group-containing copolymer resin. In the case of polymerizing, it has been found that a coating composition having excellent viscosity stability over time can be produced over a long period of time, and the present invention has been completed.

That is, the present invention relates to “(A) (i) 0.5 to 50% by weight of a vinyl monomer having an alkoxysilyl group, and (ii) another vinyl monomer copolymerizable with a vinyl monomer having an alkoxysil group. (Iii) 0.1 to 10% by weight of a carboxylic acid monomer copolymerizable with a vinyl monomer having an alkoxysilyl group and 40 to 99.4% by weight of a monomer having no carboxyl group (B) orthopropionate and / or orthobutyrate 0.5 to 30 parts by weight per 100 parts by weight of copolymer resin (C) 5 to 50 parts by weight of alkyl alcohol having 1 to 10 carbon atoms in the alkyl group (D) A stabilized coating composition comprising 0 to 500 parts by weight of a pigment. "

A feature of the present invention resides in that a carboxyl group is further present in a resin obtained by copolymerizing a monomer having an alkoxysilyl group as described above. Due to such features, the storage stability of the resin composition for coatings, particularly a system containing a copper phthalocyanine pigment, is further improved.

In the present invention, (A) (i) monomers containing an alkoxysilyl group include γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, δ-methacryloxypropylmethyldimethoxysilane, and γ-methacryloxypropyltrimethoxysilane. Acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltripropoxysilane, vinylmethyldiethoxysilane, vinyltri (ethoxymethoxy) silane, allyltrimethoxysilane, P -Vinylphenyltrimethoxysilane and the like. (Ii) Other vinyl monomers copolymerizable with these monomers and containing no carboxyl group include methyl methacrylate, ethyl methacrylate, butyl methacrylate,
Methacrylic esters such as 2-ethylhexyl methacrylate, lauryl methacrylate, benzyl methacrylate, cyclohexyl methacrylate; methyl acrylate, ethyl acrylate, butyl acrylate,
Acrylic esters such as 2-ethylhexyl acrylate, lauryl acrylate, benzyl acrylate, and cyclohexyl acrylate; aromatic unsaturated hydrocarbons such as styrene, α-methylstyrene, and vinyl toluene; β-hydroxyethyl acrylate, β-hydroxypropyl acrylate; hydroxyalkyl (meth) acrylates such as β-hydroxyethyl methacrylate and β-hydroxypropyl methacrylate; further, acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, N, N-dimethylacrylamide, diacetone acrylamide, N- (hydroxymethyl ) Acrylamide, N, N-dimethylaminoethyl methacrylate, vinyl pyridine, vinyl chloride, vinyl acetate and the like.

Further, (iii) carboxylic acid monomers copolymerizable with (i) include, for example, acrylic acid, methacrylic acid,
Crotonic acid, (anhydride) maleic acid, fumaric acid, citraconic acid, glutaconic acid, itaconic acid and the like.

Among them, particularly with respect to the viscosity stability over time of a paint containing a copper phthalocyanine pigment, acrylic acid, methacrylic acid, monocarboxylic acid monomers such as crotonic acid are effective, and other monomers are effective. The effect is not enough.

The content of the alkoxysilyl group-containing vinyl monomer (i) in the copolymer must be 0.5 to 50% by weight.
If the amount is less than 50% by weight, no improvement in the weather resistance of the film due to the siloxane bond is observed, while if the amount exceeds 50% by weight, the crosslink density is too high and the film tends to be hard. The preferred content is 2
~ 30% by weight.

Another vinyl monomer copolymerizable with these monomers (i) and a monomer containing no carboxyl group (ii)
Is required to be 40 to 99.4% by weight, and if it is less than 40% by weight, the film becomes too hard, and if it exceeds 99.4% by weight, the weather resistance is not sufficiently improved.

The preferred content is 65-97.5% by weight. Further, the carboxylic acid monomer (iii) in the copolymer needs to be 0.1 to 10% by weight, and if it is less than 0.1% by weight, the effect of the viscosity of the paint on the aging stability is not actually exhibited. In addition, the dispersion state of the pigment is insufficient, and if it exceeds 10% by weight, the physical properties of the coating film deteriorate. The preferred content is 0.5 to 5% by weight.

The (B) orthopropionate in the present invention includes trimethyl orthopropionate, triethyl orthopropionate, trimethyl orthoisopropionate,
Triethyl orthoisopropionate, and the like,
Examples of the orthobutyrate include trimethyl orthobutyrate, triethyl orthobutyrate, trimethyl orthoisobutyrate, and triethyl orthoisobutyrate.

These are used in a proportion of 0.5 to 30 parts by weight, preferably 1 to 20 parts by weight, per 100 parts by weight of (A). If the amount is less than 0.5 part by weight, the effect of maintaining the storage stability cannot be obtained, and if the amount is more than 30 parts by weight, the film is adversely affected.

(C) As the alkyl alcohol having 1 to 10 carbon atoms in the alkyl group, methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, sec-butyl alcohol, tert-butyl alcohol, n- Amyl alcohol, isoamyl alcohol, hexyl alcohol, octyl alcohol, cellosolve and the like can be mentioned. Alcohols having 10 or more carbon atoms in the alkyl group are not preferred because they are liable to dry and scatter slowly and remain in the film. The alkyl alcohol is used in an amount of 5 to 50 parts by weight, preferably 10 to 40 parts by weight, per 100 parts by weight of (A). If it is less than 5 parts by weight, the synergistic effect of maintaining the storage stability with (B) is poor, and if it is more than 50 parts by weight, the workability and film properties of the coating are adversely affected.

As the pigment (D) of the present invention, extenders such as calcium carbonate, kaolin, talc and aluminum silicate; inorganic pigments such as titanium oxide, iron oxide, graphite, cadmium oxide, carbon black, aluminum powder and zinc powder; permanents -Various organic pigments such as quinacridone-based such as red, azo-based such as Watching Red and Permanent Orange, phthalocyanine-based such as copper phthalocyanine green, sulfonated copper phthalocyanine, phthalocyanine blue, and polychlorobromocopper phthalocyanine can be used, particularly copper. The composition of the present invention exerts an effect on the storage stability of a paint using a phthalocyanine pigment.

The use amount of these pigments is not particularly limited, but is usually 0 to 500 parts by weight, preferably 2 to 100 parts by weight of (A).
It is used in a proportion of up to 200 parts by weight.

In the present invention, a copolymer of a vinyl monomer having an alkoxysilyl group, another vinyl monomer copolymerizable with the vinyl monomer, and a monocarboxylic acid monomer can be obtained by ordinary solution polymerization. The copolymer composition is crosslinked at normal temperature by atmospheric moisture in parallel with the evaporation and drying of the organic solvent, but from a practical point of view, the use of a curing catalyst is preferred. Titanates such as titanate and tetrapropyl titanate; organic tin compounds such as dibutyltin dilaurate, dibutyltin maleate, dibutyltin diacetate, tin octylate, tin naphthenate; lead octylate; butylamine, octylamine;
Dibutylamine, monoethanolamine, diethanolamine, triethanolamine, diethylenetriamine, triethylenetetramine, oleylamine, octylamine, cyclohexylamine, benzylamine, diethylaminopropylamine, xylylenediamine, triethylenediamine, guanidine, diphenylguanidine, 2,4 Amine compounds such as 1,6-tris (dimethylaminomethyl) phenol, monophorin, N-methylmorpholine, 1,3-diazabicyclo (5,4,6) undecene-7 (DBU) or salts thereof such as carboxylic acids; Low molecular weight polyamide resin obtained from excess polyamine and polybasic acid; reaction product of excess polyamine and epoxy compound;

These curing catalysts are based on 100 parts by weight of the copolymer resin.
It is used in a ratio of 0.05 to 5 parts by weight.

The coating composition of the present invention is for interior and exterior of buildings, roof tiles,
It can be used in various fields such as automobile repair, woodwork or building material coating, and coating of various plastic products.

[Action] In the present invention, the presence of the carboxylic acid-based monomer and orthopropionate and / or orthobutyrate contained as essential components in the acoxysilyl group-containing copolymer resin causes the paint to thicken due to moisture in the paint. In particular, a system using a copper phthalocyanine pigment exhibits a remarkable effect when a monocarboxylic acid monomer is used as the carboxylic acid monomer.

Next, the present invention will be described specifically with reference to examples.
“%” And “parts” are based on weight.

Production Example 1 of Resin 400 parts of methyl methacrylate, 500 parts of n-butyl methacrylate, 100 parts of γ-methacryloxypropyltrimethoxysilane, 5 parts of maleic anhydride, 420 parts of xylene, 50 parts of isopropyl alcohol, benzoyl peroxide (BPO) 2 Was charged into a flask equipped with a condenser, a stirrer and a thermometer, heated to 90 ° C. and polymerized.During polymerization, polymerization was performed for 10 hours while sequentially adding a polymerization catalyst in which 8 parts of BPO was dissolved in 30 parts of xylene. Min 50%, viscosity 2000cps / 25 ℃
The resin (a) was obtained.

Resin Production Examples 2 to 7 Polymerization was carried out according to Production Example 1 to obtain resins (a) to (g) having the compositions shown in Table 1. The resin content and viscosity of these resins are also shown in Table 1.

Examples and Comparative Examples First, 100 parts of the resins (a) to (g) were mixed with the ortho acid ester in the number shown in Table 2 respectively.
Next, the pigments shown in Table 2 were mixed with 35 parts of these resins in 33 parts for titanium oxide, 20 parts for permanent red, 7 parts for phthalocyanine pigment, and 20 parts of thinner. Then, 100 parts of glass beads were added, and the mixture was placed in a container. After sealing, the mixture was shake-dispersed with a paint conditioner for 60 minutes. Further, 65 parts of the resin was added and shaken for 10 minutes to obtain a paint.

Table 2 also shows the dispersion state of the obtained paint and the measurement results of the viscosity of the paint after one month at 50 ° C.

[Effects] In the present invention, the viscosity of the resin coating over time is stabilized by the presence of a carboxylic acid monomer and orthopropionate and / or orthobutyrate which are contained as essential components in the alkoxysilyl group-containing copolymer resin. Can be achieved,
Particularly, for a system using a copper phthalocyanine pigment widely used as a blue paint, it is industrially useful in that it is effective when a monocarboxylic acid monomer is used as the carboxylic acid monomer. is there.

Continuation of the front page (51) Int.Cl. ⁶ identification code FI C09D 143/04 C09D 143/04 (56) References JP-A-2-58556 (JP, A) JP-A-2-733861 (JP, A) JP-A-1-131271 (JP, A) JP-A-63-183944 (JP, A) JP-A-57-55953 (JP, A) JP-A-60-76518 (JP, A) (58) (Int.Cl. ⁶ , DB name) C08L 1/00-101/14 C09D 1/00-201/10 C08K 5/00-5/59

Claims (2)

(57) [Claims] (1) (A) 0.5 to 50% by weight of a vinyl monomer having an alkoxysilyl group (ii) Another vinyl monomer copolymerizable with a vinyl monomer having an alkoxysilyl group (Iii) a copolymer comprising 0.1 to 10% by weight of a carboxylic acid monomer copolymerizable with a vinyl monomer having an alkoxysilyl group and 40 to 99.4% by weight of a monomer having no carboxyl group. (B) orthopropionate and / or orthobutyrate 0.5 to 30 parts by weight based on 100 parts by weight of polymer resin (C) alkyl alcohol having 1 to 10 carbon atoms in the alkyl group 5 to 50 parts by weight (D) pigment A stabilized coating composition comprising 0 to 100 parts by weight. 2. The composition according to claim 1, wherein a copper phthalocyanine pigment is blended as the pigment.