JP2000256620A - Coating agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the storage stability of a coating agent comprising a silane compd. having an alkoxy group. SOLUTION: This coating agent comprises an org. silane compd. having a 1-3C alkoxysilyl group, and an alcohol with the total carbon number larger than that of the alkyl group in the alkoxylsilyl group of the org. silane compd., and does not cause clouding or gelling for two months or longer when stored in a hermetic state at 50 deg.C. The agent pref. comprises a basic compd.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating agent for coating films and various substrates, and more particularly to a coating agent containing a silane compound having a hydrolyzable group and having difficulty in controlling a polycondensation reaction. The present invention relates to a coating agent which exhibits excellent storage stability while having excellent storage stability.

[0002]

2. Description of the Related Art Alkoxysilane compounds are hydrolyzed and condensed with water to form a dense film, and are therefore used in various fields as coating agents and the like. When used as a coating agent, a method of rapidly coating the substrate with a hydrolyzed and condensed product to some extent is usually employed, because there is a problem in storage stability as a coating agent. That is, for example, a silane compound having an alkoxyl group such as a methoxy group is extremely liable to cause a condensation reaction, and forms a three-dimensional cured polymer and gels even when stored in a sealed state. Further, cloudiness often occurs due to the difference in solubility between the polycondensed polymer and the silane monomer. Since a coating agent that has gelled or clouded can no longer form a uniform film as a coating agent, there has been a problem that an expensive organic silane compound is wasted.

[0003]

Accordingly, an object of the present invention is to improve the storage stability of a coating agent containing a silane compound having an alkoxysilyl group.

[0004]

The coating agent of the present invention, which has solved the above-mentioned problems, comprises an organic silane compound having an alkoxysilyl group having 1 to 3 carbon atoms, and an alkyl group in the alkoxysilyl group of the organic silane compound. It contains an alcohol having a total number of carbon atoms larger than that of carbon atoms, and has a gist in that it does not cause clouding or gelation for more than 2 months when stored at 50 ° C. in a closed state. A coating agent having a basic compound may be used. This is because the effect of improving the stabilization of the present invention is further exhibited.

More specifically, the coating agent of the present invention can react with an organic compound (A) having a functional group (excluding an alkoxysilyl group) and a functional group of the organic compound (A). Functional group and Si (OR ¹ )
An organic silane compound (B) having a group (R ¹ is an alkyl group having 1 to 3 carbon atoms) and / or a hydrolytic condensate thereof, and an organic silane compound (C) represented by the following general formula (C) and / or its hydrolysis condensation _{^{product, R 2 m Si (oR 3}} ) n ... (C) ( wherein, R ² may be the same or different, a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an aryl group, a vinyl Represents a functional group directly bonded to a group or a carbon chain, R ³ may be the same or different and represents an alkyl group having 1 to 3 carbon atoms, m is 0 or a positive integer, n is an integer of 1 or more, And m + n is 4.) and the organosilane compound (B)
Number of carbon atoms of R ¹ and R ^{3 in} organosilane compound (C)
Is a coating agent that contains an alcohol (D) having a larger total number of carbon atoms than that of (a) and does not cause clouding or gelling for more than 2 months when stored at 50 ° C. in a closed state.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The coating agent used in the present invention contains a silane compound as an essential component and an alcohol as a solvent. And, it is characterized in that an alcohol having more carbon atoms than the alkyl group of the alkoxysilyl group of the silane compound is used as the alcohol. By adopting this configuration, a coating agent that does not cause clouding or gelation for more than two months when stored at 50 ° C. in a closed state has been successfully provided. Hereinafter, the present invention will be described in detail. In the following description, “good storage stability” means that when the coating agent is stored at 50 ° C. in a closed state, no clouding or gelation occurs for 2 months or more.

[0007] Alcohol, an essential component of the present invention, is used as a solvent for a coating agent. At this time, it is necessary to use an alcohol having a larger number of carbon atoms than the alkyl group (R) of the alkoxysilyl group (SiOR) of the organosilane compound, which is also an essential component (hereinafter, may be referred to as a specific alcohol). is there. That is, when the silane compound has, for example, a methoxy group,
That is, an alcohol having 2 or 3 carbon atoms, such as ethanol or 2-propanol, or an alcohol having 4 or more carbon atoms is used. In the case where a silane compound is used in combination and one silane compound contains a methoxy group and another silane compound contains an ethoxy group, the silane compound has more carbon atoms (three or more carbon atoms) than ethyl. Alcohol (such as 2-propanol) must be used. Of course, ethanol may be used in combination. Since the boiling point of alcohols generally increases as the number of carbon atoms increases, it is preferable that the difference in the number of carbon atoms between the alkoxyl group and the alcohol be one in consideration of the drying property of the coating step.

The reactivity of an alkoxyl group decreases as the number of carbon atoms increases. The reactivity of the ethoxy group is much lower than the most reactive methoxy group, even with one more carbon atom. Therefore, even if the silane compound has a highly reactive methoxy group by adopting the above configuration, part of the methoxy group is an alkoxyl group having a large number of carbon atoms (eg, an ethoxy group or a propoxy group) due to the alcohol exchange reaction. To reduce the reactivity of the silane compound. Therefore, the storage stability is improved.

Usually, the alcohol exchange reaction reaches an equilibrium, and not all of the methoxy groups cause an alcohol exchange reaction. However, the reactivity of ethoxy groups is much lower than that of methoxy groups, so that even if all methoxy groups are not converted to ethoxy groups or propoxy groups, only a few percent of methoxy groups are converted and storage stability is significantly improved. I do.

[0010] When a silane compound having an alkoxysilyl group having low reactivity is used from the beginning as much as emphasis is placed on storage stability, the progress of the polycondensation reaction after film formation is slowed down, and the drying and drying of the coating film is slowed down. Since the curing is slow, the productivity is reduced. Therefore, it is possible to use a compound having a methoxy group as the silane compound and maintain the storage stability by the constitution of the present invention, and to keep the hydrolysis-condensation polymerization after coating at a high speed by the methoxy group not participating in the alcohol exchange reaction. It is necessary.

In this sense, if all of the solvent is the above-mentioned specific alcohol, the ratio of methoxy groups that cause an alcohol exchange reaction increases, and the reactivity after coating may decrease, which is not preferable. It is recommended that the specific alcohol content be 3 to 60% by weight. If the specific alcohol is less than 3% by weight, the storage stability aimed at by the present invention cannot be secured, and if it exceeds 60% by weight, the progress rate of the polycondensation reaction may decrease. The lower limit is more preferably 5% by weight, and still more preferably 6% by weight.
% By weight. More preferably, the upper limit is set to 10% by weight.

Solvents that can be used other than the specific alcohol include methanol, ethanol, 2-propanol, and irrespective of the carbon number of the alkoxysilyl group of the silane compound.
Alcohols such as butanol and ethylene glycol are exemplified. In addition to the alcohols, any solvent that can dissolve or disperse the components of the coating agent can be used in combination. Specifically, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, aromatic hydrocarbons such as toluene, benzene and xylene, hydrocarbons such as hexane, heptane and octane, and esters such as ethyl acetate and butyl acetate And others, such as tetrahydrofuran, propyl ether, and water. One or more of these may be mixed and used in combination with the above specific alcohol.

The amount of the solvent used in the coating agent is not particularly limited, but is preferably 20 to 85% by weight based on the total weight. When the amount is less than 20% by weight, the viscosity of the coating agent may increase during coating and uniform coating may not be performed. In some cases, the thickness cannot be secured.

The coating agent of the present invention must contain an organic silane compound having an alkoxysilyl group having 1 to 3 carbon atoms as an essential component. This is because the purpose of the present invention is to stabilize such an organic silane compound. It is most preferable that the alkoxysilyl group of the organic silane compound is a methoxysilyl group, and the stabilizing effect of the present invention is exhibited, and at the same time, a curing reaction occurs promptly in the coating step, and the shortening of the drying time is also achieved. be able to.

Further, the coating agent of the present invention may have a basic compound. The basic compound is an inorganic basic compound such as ammonia or an organic basic compound such as triethylamine, and functions as a catalyst for a hydrolysis reaction of an alkoxysilyl group. Such a catalyst is
Increase the speed of curing and drying in the coating process,
Since the storage stability of the coating agent containing the catalyst is deteriorated, it is preferable from this point that the coating agent should exhibit the stabilizing effect of the present invention. As such a coating agent, not only the case where the above compound is added as a catalyst to the coating agent as a basic compound, but also an organic silane compound as an essential component and an organic silane compound contained in a specific coating agent described later ( The case where the main compound itself in the coating agent is a basic compound having a basic portion, such as the case where B) has an amino group, is included.

The coating agent of the present invention has 1 to 3 carbon atoms.
The essential components are an organic silane compound having an alkoxysilyl group, and an alcohol having a greater total number of carbon atoms than the alkyl group in the alkoxysilyl group. Other components are not particularly limited, but in order to form a flexible film that is tough and free of cracks, other components that can form a film together with the organic silane compound are used. Is preferred. Such a coating agent will be described below.

The coating agent includes an organic compound (A) having a functional group (excluding an alkoxysilyl group), a functional group capable of reacting with the functional group of the organic compound (A), and Si (OR ¹ ) An organic silane compound (B) having a group (R ¹ is an alkyl group having 1 to 3 carbon atoms) and / or a hydrolytic condensate thereof, and an organic silane compound (C) represented by the following general formula (C) and / or its hydrolysis condensation _{^{product, R 2 m Si (oR 3}} ) n ... (C) ( wherein, R ² may be the same or different, a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an aryl group, a vinyl Represents a functional group directly bonded to a group or a carbon chain, R ³ may be the same or different and represents an alkyl group having 1 to 3 carbon atoms, m is 0 or a positive integer, n is an integer of 1 or more, And m + n is 4.) and organic An alcohol (D) having a larger total number of carbon atoms than the number of carbon atoms of R ^{1 in} the silane compound (B) and the number of carbon atoms of R ^{3 in} the organic silane compound (C).

The organic compound (A) is not particularly limited as long as it has a functional group other than the alkoxysilyl group. Since the organic compound (A) does not have an alkoxysilyl group, it does not participate in the hydrolysis condensation reaction of the organic silane compound (B) or the organic silane compound (C).
A film formed only with a silane compound has a drawback of being hard but brittle (poor in impact resistance). However, by adding an organic compound (A) to a coating agent, the film becomes flexible and flexible. Can be provided. Although the organic compound (A) does not participate in the hydrolysis-condensation reaction, it reacts with the organic silane compound (B) by the functional group of (A) and is incorporated into the polymer chain constituting the coating. Thus, a so-called soft segment portion is formed in the polymer chain constituting the coating. Therefore, the impact resistance of the coating can be improved without lowering the hardness, the strength, and the denseness.

The organic compound (A) needs to be a compound having a functional group other than the alkoxysilyl group, but the type of the functional group is not particularly limited. Various functional groups can be used depending on the combination of Among them, a combination of an amino group and an epoxy group is preferable because the reaction rate is high and the coating is quickly cured. As the organic compound (A), the functional group is 2
A compound having more than one compound is also effective for speeding up curing.

In a preferred embodiment of the coating agent,
Organic compound (A) is an epoxy group, an isocyanate group,
Examples of the configuration include a compound having at least one functional group selected from the group consisting of a carboxyl group or an anhydride thereof, an oxazolinyl group, a halogenated alkyl group, and a hydroxyl group. Especially, it is preferable to have an epoxy group. In this case, it is recommended that the organic silane compound (B) has an alkoxysilyl group and an amino group.

In another preferred embodiment of the coating agent, the organic compound (A) is a compound having an amino group, in particular, a polymer compound having a molecular weight of 200 or more provides flexibility to the coating film. It is preferable from the viewpoint of doing. More preferably, they are polyethylene imines. In this case, the organic silane compound (B) is an organic silane compound having a functional group capable of reacting with an amino group together with an alkoxysilyl group, and particularly a compound having an epoxy group. Preferably, there is.

Specific examples of the organic compound (A) having an amino group include allylamine, diallylamine, isopropylamine, diisopropylamine, iminobispropylamine, ethylamine, diethylamine, 2-ethylhexylamine, 3-ethoxypropylamine, and diisobutylamine. , 3-diethylaminopropylamine, di-2-ethylhexylamine, dibutylaminopropylamine, propylamine, dimethylaminopropylamine, methyliminobispropylamine, 3-methoxypropylamine, ethylenediamine, 1,4-diaminobutane, 1, 2-diaminopropane, 1,3-diaminopropane, hexamethylenediamine, ethanolamine,
Low molecular weight organic compounds having one or more amino groups such as diethanolamine; polyethyleneimines, for example, Epomin series (Nippon Shokubai Co., Ltd. (Epomin SP-003, Epomin SP-006, Epomin SP-012, Epomin SP)
-018, Epomin SP-103, Epomin SP-11
0, epomin SP-200, epomin SP-300, epomin SP-1000, epomin SP-1020, etc.),
Polyallylamines (for example, PAA-L manufactured by Nitto Boseki Co., Ltd.
PAA-H, etc.), homopolymers of amino group-containing (meth) acrylates such as dimethylaminoethyl (meth) acrylate and diethylaminoethyl (meth) acrylate, and these amino group-containing (meth) acrylates and other (meth) acrylates And copolymers with (meth) acrylic acid, and high molecular organic compounds containing amino groups such as polyoxyethylene alkylamines.

Specific examples of the organic compound (A) having an epoxy group suitably used in the present invention include ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, triethylene glycol diglycidyl ether, tetraethylene glycol diglycidyl ether, Nonaethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, dipropylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, 1,6
Aliphatic diglycidyl ethers such as hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, glycerol diglycidyl ether;
Glycerol triglycidyl ether, diglycerol triglycidyl ether, triglycidyl tris (2-
(Hydroxyethyl) isocyanurate, polyglycidyl ethers such as trimethylolpropane triglycidyl ether and pentaerythritol tetraglycidyl ether; aliphatic and aromatic diglycidyl esters such as adipic acid diglycidyl ester and o-phthalic acid diglycidyl ester; Bisphenol A diglycidyl ether, resorcinol diglycidyl ether, hydroquinone diglycidyl ether, bisphenol S diglycidyl ether, bisphenol F diglycidyl ether,
And compounds represented by the following formula

[0024]

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Glycidyls having an aromatic ring or a hydrogenated ring thereof (including a nuclear-substituted derivative); or oligomers having a glycidyl group as a functional group (for example, in the case of bisphenol A diglycidyl ether oligomer, Can be expressed);

[0026]

Embedded image

And the like.

Hexamethylene diisocyanate,
Isocyanates such as tolylene diisocyanate, 1,4-diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, triphenylmethane triisocyanate, tolidine diisocyanate, xylylene diisocyanate, dicyclohexylmethane diisocyanate; dicarboxylic acids such as tartaric acid and adipic acid; polyacrylic Carboxyl-containing polymers such as acids; and oxazolinyl group-containing polymers can also be used as the organic compound (A). One or more of these may be used. Among the organic compounds (A) exemplified above, compounds having an aromatic ring or a hydrogenated ring thereof (including a nuclear-substituted derivative) have an effect of improving the water resistance of the coating.

The organic silane compound (B) has a functional group capable of reacting with the functional group of the organic compound (A) and Si.
It is a compound having an (OR ¹ ) group (R ¹ is an alkyl group having 1 to 3 carbon atoms). That is, it corresponds to a silane compound having an alkoxysilyl group having 1 to 3 carbon atoms, which is an essential component of the coating agent of the present invention. It is necessary to determine the functional group of the organic silane compound (B) according to the functional group of the organic compound (A).

Specifically, N-β (aminoethyl) γ-
Aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropyltriethoxysilane, N-β
(Aminoethyl) γ-aminopropyltriisopropoxysilane, N-β (aminoethyl) γ-aminopropyltributoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldiethoxysilane, N
-Β (aminoethyl) γ-aminopropylmethyldiisopropoxysilane, N-β (aminoethyl) γ-aminopropylmethyldibutoxysilane, N-β (aminoethyl) γ-aminopropylethyldimethoxysilane, N-
β (aminoethyl) γ-aminopropylethyldiethoxysilane, N-β (aminoethyl) γ-aminopropylethyldiisopropoxysilane, N-β (aminoethyl) γ-aminopropylethyldibutoxysilane, γ-
Aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltriisopropoxysilane, γ-aminopropyltributoxysilane, γ-aminopropylmethyldimethoxysilane, γ-
Aminopropylmethyldiethoxysilane, γ-aminopropylmethyldiisopropoxysilane, γ-aminopropylmethyldibutoxysilane, γ-aminopropylethyldimethoxysilane, γ-aminopropylethyldiethoxysilane, γ-aminopropylethyldiiso Propoxysilane, γ-aminopropylethyldibutoxysilane, γ-aminopropyltriacetoxysilane, γ-
(2-ureidoethyl) aminopropyltrimethoxysilane, γ- (2-ureidoethyl) aminopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, N-β- (N-vinylbenzylaminoethyl)-
Amino group-containing compounds such as γ-aminopropyltrimethoxysilane; β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane, β- (3,4
-Epoxycyclohexyl) ethyltriisopropoxysilane, β- (3,4-epoxycyclohexyl) ethylmethyldimethoxysilane, β- (3,4-epoxycyclohexyl) ethylmethyldiethoxysilane, γ-glycidoxypropyltrimethoxysilane Epoxy group-containing compounds such as, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltriisopropoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane; Or γ-isocyanopropyltrimethoxysilane, γ-isocyanopropyltriethoxysilane, γ-
Isocyanopropylmethyldimethoxysilane, isocyanate group-containing compounds such as γ-isocyanopropylmethyldiethoxysilane; mercapto group-containing compounds such as γ-mercaptopropyltrimethoxysilane and γ-mercaptopropyltriethoxysilane; and the like. One or more kinds can be used. In addition, these organic silane compounds (B) must be selected so that they can react with the functional group of the organic compound (A).

The organic silane compound (B) reacts with the organic compound (A) and has a hydrolyzable group of Si (O
R ¹ ) group (R ¹ has the same meaning as described above), so that hydrolysis condensation proceeds before or after the reaction with the organic compound (A), and the hydrolysis of the organic silane compound (C) described later. Since the polycondensation proceeds due to co-hydrolytic condensation with the decomposable condensed group, a dense film can be formed quickly. It also has the effect of increasing the adhesion between the coating and the substrate.
The organic silane compound (B) may be previously used alone, or may be subjected to (co) hydrolytic condensation polymerization with the organic silane compound (C). This is because volatilization of the organic silane compound (B) and the organic silane compound (C) during coating can be prevented, and a film can be formed more quickly. When a low molecular weight compound is used as the organic compound (A), it is preferable to carry out hydrolytic condensation in advance.

The organic silane compound (C) used in the present invention is not particularly limited as long as it is represented by the following general formula (C). This organic silane compound (C)
Can be distinguished from the organic silane compound (B) in that it has no functional group capable of reacting with the functional group of the organic compound (A), but has an alkoxysilyl group like the organic silane compound (B). Therefore, it corresponds to a silane compound which is an essential component of the coating agent. R ² _m Si (OR ³ ) _n ... (C) (wherein R ² may be the same or different and is directly connected to a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an aryl group, a vinyl group or a carbon chain) R ³ may be the same or different and represents an alkyl group having 1 to 3 carbon atoms, m is 0 or a positive integer, n is an integer of 1 or more, and m + n is 4. .).

The organic silane compound (C) enhances the adhesion to the base material and forms a dense film of a polysiloxane skeleton together with the organic silane compound (B), so that a film having excellent heat resistance can be formed. Can be.

As specific examples, tetramethoxysilane,
Tetraethoxysilane, tetraisopropoxysilane,
Tetrabutoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltriisopropoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltriisopropoxysilane, ethyltributoxysilane, dimethyldimethoxysilane, Examples thereof include dimethyldiethoxysilane, dimethyldiisopropoxysilane, dimethyldibutoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, diethyldiisopropoxysilane, and diethyldibutoxysilane. Among them, tetramethoxysilane and tetraethoxysilane are preferable from the viewpoint of the reactivity and the improvement of the water resistance of the film.

An organic metal compound having the same effect as the organic silane compound (C) can be used as one of the components of the coating agent. Specifically, titanium tetraethoxide, titanium tetraisopropoxide, titanium alkoxides such as titanium tetrabutoxide, zirconium tetraethoxide, zirconium tetraisopropoxide, zirconium alkoxides such as zirconium tetrabutoxide, aluminum triethoxide, Aluminum alkoxides such as aluminum triisopropoxide and aluminum tributoxide;

The (co) hydrolysis-condensation reaction of the organosilane compound (B), the organosilane compound (C), or both of them proceeds with moisture in the air. However, when a known catalyst such as an acid or a base is used, It can be performed efficiently. If the hydrolysis reaction is carried out in the above-mentioned solvent, it can be stored as it is, which is convenient. In addition, the hydrolysis and condensation polymerization reaction is performed in a solvent other than the specific alcohol that reduces the reaction rate, and after the desired degree of polymerization is reached, the specific alcohol is added to ensure storage stability, and the container may be sealed and stored. Good.

The coating agent described above essentially contains an organic compound (A), an organic silane compound (B), an organic silane compound (C) and an alcohol (D). As the alcohol (D), ^one of R ¹ of Si (OR ¹ ) of the organic silane compound (B) and R ³ of Si (OR ³ ) of the organic silane compound (C), whichever has the larger number of carbon atoms, An alcohol having a higher total carbon number than the carbon number must be used. For example, R ¹ is a methyl group and R ³
Is an ethyl group, an alcohol having 3 or more carbon atoms is used. In this case, if ethanol is used together,
Since a methyl group can be converted to an ethyl group and an ethyl group can be converted to an alkyl group equal to or more than a propyl group, the storage stability can be improved without significantly reducing the hydrolytic condensation reactivity.

Next, preferred amounts of the respective compounds when the total amount of the respective compounds other than the solvent in the coating agent is 100% by weight will be described. Organic compound (A) is 1-4
0% by weight is preferred. When the amount of the organic compound (A) is less than 1% by weight, the flexibility of the coating film is insufficient, and the effect of improving the impact resistance may not be exhibited. If the amount is more than 40% by weight, the amount of the organic silane compound (B) or the organic silane compound (C) decreases, so that a dense and strong film cannot be obtained. More preferably, the amount of (A) used is in the range of 5 to 30% by weight, and still more preferably 5 to 20% by weight.

The content of the organic silane compound (B) is preferably 0.5 to 80% by weight. If the amount of the organic silane compound (B) is less than 0.5% by weight, the adhesion of the film to the substrate is not good, but if it is more than 80% by weight, the moisture resistance of the film tends to be poor. The more preferred amount of the organic silane compound (B) is in the range of 1 to 70% by weight, and more preferably 1 to 6% by weight.
0% by weight.

5 to 90% by weight of the organic silane compound (C)
Is preferred. When the amount of the organic silane compound (C) is less than 5% by weight, the moisture resistance of the coating may be insufficient. But 9
If it is used in excess of 0% by weight, the amount of the organic compound (A) used is reduced, so that the flexibility of the film is reduced. A more preferred amount of the organic silane compound (C) is in the range of 10 to 90% by weight, and further preferably 30 to 80% by weight.
It is.

The method for preparing the coating agent is not particularly limited, but the organic compound (A), the organic silane compound (B) and / or its hydrolytic condensate, the organic silane compound (C) and / or its hydrolytic condensate and , A method in which a functional group reaction between the organic compound (A) and the organic silane compound (B) is performed in advance, and then the organic silane compound (C) and / or a hydrolyzed condensate thereof are added. A method of (co) hydrolyzing and condensing an organic silane compound (B) and an organic silane compound (C) in the presence of A), after co-hydrolyzing and condensing an organic silane compound (B) and an organic silane compound (C); A method of reacting with the organic compound (A) is exemplified.

If necessary, various inorganic and organic additives such as a curing catalyst, a wettability improver, a plasticizer, an antifoaming agent and a thickener are added to the coating agent of the present invention. You can also.

The substrate on which the coating film of the present invention can be formed is not particularly limited. It can be coated on anything such as plastic, wood, knit, woven, non-woven, paper, synthetic paper, metal, metal foil. Commonly used substrates include plastic films,
Alternatively, a resin molded body such as a bottle, a container, or various molded articles may be used instead of a thin material such as a film.

The types of plastics constituting the film and the molded product are not particularly limited.
Polyester, polyamide resin, poly (meta) such as olefin resin such as polypropylene, styrene resin such as polystyrene, polyethylene terephthalate, polyethylene isophthalate, polyethylene-2,6-naphthalate, polybutylene terephthalate and copolymers thereof.
Acrylic resins such as acrylic acid and its esters, polyoxymethylene, polyacrylonitrile, polyvinyl acetate, ethylene-vinyl acetate copolymer (EVA), polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl alcohol copolymer Coalescence, polyetherketone, polycarbonate, cellophane, polyethersulfone, polysulfone, polyphenylenesulfone,
Thermoplastic resins such as polyimide, ionomer resin, and fluororesin, and thermosetting resins such as melamine resin, polyurethane resin, epoxy resin, phenol resin, unsaturated polyester resin, alkyd resin, urea resin, and silicon resin can be preferably used. Of course, two or more of these laminates may be used as the base material.

The method of coating the above-mentioned base material with a coating agent is not particularly limited, and examples thereof include a roll coating method, a dip coating method, a bar coating method, a nozzle coating method, a die coating method, a spray coating method, and a combination thereof. Can be adopted. Since the coating agent of the present invention has excellent storage stability, not only a bar coating method but also a dip coating method and a roll coating method can be used, but the coating agent may gel when exposed to air. It is preferable to use a nozzle coating method, a spray coating method, or a die coating method, which can keep the coating agent from contacting air to the outlet. The thickness of the coating is not particularly limited, but is usually in the range of 0.1 to 20 μm after drying.

The coating agent is coated on the whole or a part of the resin molded product, or on one or both surfaces of the film. It is recommended that drying after coating be performed in a heating / humidifying step of 50 ° C. or more and RH of 5% or more, since a dense film can be formed with good drying efficiency. Before the coating agent is applied, a known anchor coat layer such as a urethane resin may be provided on the substrate.

The coating with the coating agent of the present invention includes:
Other layers may be laminated. Laminating means, as a substrate, a coating method, an extrusion method, a dry lamination, a wet lamination, a material laminated in advance by a lamination method such as a hot melt lamination or the like, or after coating the coating agent of the present invention, Means for laminating by a known method such as coating another layer or performing vapor deposition can be adopted. The material to be laminated is
Known materials that can be used as the base material can be used. If necessary for lamination, a known adhesive may be used.

The coating film of the present invention has sufficient strength and hardness, and has abrasion resistance, impact resistance, heat resistance,
Since it is excellent in flexibility, transparency, moisture resistance, solvent resistance, and the like, it can be applied to various uses for forming a protective film and for various other purposes.

[0049]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which do not limit the present invention.
Modifications and alterations that do not depart from the spirit described below are all included in the technical scope of the present invention.

The storage stability is a result of visually observing a period until the film becomes clouded or gelled when the coating agent is sealed in a sealable container and stored in an atmosphere at 50 ° C.

Example 1 20 g of tetramethoxysilane and 23.3 of 2-propanol were placed in a flask equipped with a stirrer, thermometer, and condenser.
g, 9.0 g of water and 0.5 g of 0.1N hydrochloric acid were charged and stirred at 30 ° C. for 4 hours to obtain a coating agent 1. When the storage stability of this coating agent 1 was observed, it took 5 months to become cloudy.

Example 2 γ was added to a flask equipped with a stirrer, thermometer, and condenser.
20 g of glycidoxypropyltrimethoxysilane, 22.6 g of ethanol, 4.0 g of water and 0.6 g of 0.1N hydrochloric acid were charged and stirred at 30 ° C. for 4 hours to obtain a coating agent 2. When the storage stability of this coating agent 2 was observed, it took 9 months to become cloudy.

Example 3 γ was added to a flask equipped with a stirrer, thermometer, and condenser.
After 100 g of aminopropyltrimethoxysilane, 50 g of methanol and 30 g of toluene were charged and heated to 70 ° C., 10 g of bisphenol A diglycidyl ether was added dropwise over 30 minutes. After further aging at 70 ° C. for 3 hours, the mixture was cooled to room temperature, and 6.0 g of water and 30 g of methanol were added.
Was added and stirred at room temperature for 1 hour to ripen. Further, 84.9 g of tetramethoxysilane and ethanol 1
A mixed solution of 5.0 g and 41.1 g of methanol was added to obtain a coating agent 3. When the storage stability of this coating agent 3 was observed, it took four months to become cloudy.

Example 4 In Example 3, 10 g of bisphenol A diglycidyl ether was added to resorcinol glycidyl ether.
A coating agent 4 was obtained in the same manner as in Example 3 except that the amount was changed to 3 g. When the storage stability of this coating agent 4 was observed, it took three months to become cloudy.

Example 5 In a flask equipped with a stirrer, a thermometer, and a cooler, 8.0 g of polyethyleneimine “Epomin SP200” (manufactured by Nippon Shokubai Co., Ltd.), 3.0 g of γ-glycidoxypropyltrimethoxysilane, After charging 21 g of ethanol, the temperature was raised to 70 ° C., the mixture was aged at 70 ° C. for 3 hours, cooled to room temperature, and a mixed solution of 2.0 g of water and 5 g of ethanol was added.
The mixture was aged by stirring at room temperature for 1 hour. To this solution, a tetramethoxysilane oligomer “M silicate 51” was added.
A mixture of 15.0 g (manufactured by Tama Chemical Co., Ltd.) and 46.0 g of ethanol was added to obtain Coating Agent 5. When the storage stability of this coating agent 5 was observed, it took four months to become cloudy.

Comparative Example 1 A comparative coating agent 1 was obtained in the same manner as in Example 3, except that ethanol was changed to methanol. When the storage stability of this comparative coating agent 1 was observed, it became cloudy in one month.

[0057]

The coating agent of the present invention contains a hydrolyzable silane compound and an alcohol having a carbon number larger than that of the alkyl group of the alkoxysilyl group of the silane compound as a solvent. Excellent storage stability. The coating agent of the present invention can maintain a stable state for 2 months or more in a closed state even under a high temperature condition of 50 ° C., and maintain a stable state for a long time at room temperature or refrigerated storage. Can be.

Claims (3)

[Claims] 1. An organic silane compound having an alkoxysilyl group having 1 to 3 carbon atoms, and an alcohol having a total number of carbon atoms larger than that of an alkyl group in the alkoxysilyl group of the organic silane compound, 50 ° C in a closed state
A coating agent which does not cause clouding or gelling for 2 months or more when stored in the above. 2. The coating agent according to claim 1, which contains a basic compound. 3. A coating agent comprising an organic compound (A) having a functional group (excluding an alkoxysilyl group), a functional group capable of reacting with the functional group of the organic compound (A), and Si (OR ¹ An organic silane compound (B) having a group (R ¹ is an alkyl group having 1 to 3 carbon atoms) and / or a hydrolytic condensate thereof, and an organic silane compound (C) represented by the following general formula (C) and / or Or a hydrolyzed condensate thereof, and R ² _m Si (OR ³ ) _n ... (C) (wherein R ² may be the same or different and a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an aryl group) , A vinyl group or a functional group directly bonded to a carbon chain, R ³ may be the same or different and represents an alkyl group having 1 to 3 carbon atoms, m is 0 or a positive integer, and n is an integer of 1 or more. And m + n is 4.), and Machine silane compound (B)
Number of carbon atoms of R ¹ and R ^{3 in} organosilane compound (C)
A coating agent comprising an alcohol (D) having a larger total number of carbon atoms than that of (a), and not causing clouding or gelling for 2 months or more when stored at 50 ° C in a closed state.