JP2000265061A - Composition for epoxy resin/silicon hybrid material, coating agent, and method for surface-coating plastic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition which can give a coating film excellent in water resistance, scratch resistance, etc., to the surface of a plastic material without the necessity for pretreatment by including an alkoxysilane mixture containing a tetraalkoxysilane and an amino-containing alkoxysilane with an epoxy resin. SOLUTION: It is desirable that the tetraalkoxysilane comprises an organosilicon compound of the formula: Si(OR)4 and/or a partial hydrolyzate thereof and/or that the amino-containing alkoxysilane comprises an organosilicon compound of the formula: R11R2mmSi(OR3)n and/or a partial hydrolyzate thereof. In the formulae, R is a lower alkyl; R1 is an amino-containing alkyl; R2 is R; R3 is H or R; l is 1-2; m is 0-2; n is 1-3; and l+m+n=4. It is desirable that the composition is a non-water-based one. The composition can be used as a coating agent. It can give a coating film excellent in solvent resistance, heat resistance, weathering resistance, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition for epoxy resin-silicon hybrid material, a coating agent, and a method for coating a plastic surface. The coating agent of the present invention is particularly useful for coating a sensitive plastic surface such as a polycarbonate resin. Such modified plastics with improved surface properties can be used for large-sized products such as various molded products, such as sundries and daily necessities, aircraft windows and doors, motorcycle windshields, headlights and various lighting fixture covers, signs and displays. It can be used for structures, meter panels, equipment covers, etc.

[0002]

2. Description of the Related Art Plastic materials typified by polycarbonate, methacrylic resin, polyethylene terephthalate, polyvinyl chloride and the like are required to have transparency, such as glass substitutes, because they are lighter and more excellent in crush resistance than glass materials. Is widely used in various applications. Above all, polycarbonate is one of these transparent plastic materials, which is tough and excellent in impact resistance, heat resistance, good dimensional stability, and the like, and is therefore a plastic material that has received much attention as a glass substitute material in the future. However, these transparent plastic materials are lightweight and have better crush resistance than glass materials, but because of their insufficient surface hardness, wiping work to remove dust, dirt, etc., friction, scratching, etc.
There is a disadvantage in that the surface is easily scratched, and thus gloss and transparency are easily lost during use. Further, these plastic substrates are easily attacked by an organic solvent, lack chemical resistance, and have a problem in weather resistance such as light deterioration.

Heretofore, as a method of improving the disadvantages of these transparent plastic materials, a plastic substrate surface is coated with a coating having high hardness. As a specific method, various organopolysiloxane-based coating agents have been known for a long time. Organopolysiloxane-based coating agents have a large cross-linking density as a characteristic of siloxane bonds, and have excellent weather resistance and a very high hardness hard coat layer obtained by a simple method. It is used as a coating agent for molded articles of complicated shapes and molded articles of complicated shapes. Such organopolysiloxane-based coatings are those in which alkoxysilanes are hydrolyzed to form organopolysiloxanes through polycondensation through the formation of silanol groups and are cured. The structural units of organosilanes such as alkoxysilanes are monofunctional. From monofunctional to tetrafunctional.

A cured film made of a tetrafunctional alkoxysilane is not used as it is because it has poor film-forming properties and lacks adhesiveness. In order to fuse the formed silica particles. An example of practical application is a composite of an organic polymer consisting of a copolymer of a hydrolysis / polycondensate of a tetrafunctional alkoxylane and a fluorinated olefin such as tetrafluoroethylene with vinyl acetate or hydroxyalkyl vinyl ether. The body is known (US Pat. Nos. 3,429,845 and 3,429,843).
No. 6).

As a method of using a trifunctional alkoxysilane, a method of obtaining a curable ladder structure resin which is first hydrolyzed and condensed, redissolved in a solvent, added with a curing catalyst, and thermally cured. Known (U.S. Pat. No. 34
Nos. 51838 and 3554698).

However, these organosiloxane-based coating agents generally have a considerably low curing rate and use a condensation reaction of silanol groups, so that water-resistance such as cracking, peeling, coloring (whitening), etc. occurs upon contact with moisture. Poor plasticity, such as polycarbonate resin, has poor wettability, and even when used in combination with a surfactant, has poor adhesion to the substrate, so it is easy to peel off. It has the disadvantage of lacking. In order to avoid these drawbacks, treatment with a general silane coupling agent such as a silane coupling agent such as 3-glycidoxypropyltrimethoxysilane or 3-aminopropyltrimethoxysilane, or a silane containing an amino group A reaction product comprising a compound and an acid anhydride (JP-A-56-16573), a reaction product comprising a silane compound having an amino group and an epoxy resin (JP-A-51-2736), thermoplastic acrylic Resins (JP-A-52-138565, JP-A-58-19)
It is indispensable to select and use an appropriate primer such as that described in JP-A-6237.

[0007] In recent years, composite compositions with various organic substances have been proposed as a method for addressing such disadvantages. For example, using a copolymer of an acrylic monomer or the like and a monomer having an alkoxysilyl group such as vinyltrimethoxysilane, a composite of an acrylic resin and a polysiloxane is formed, and adhesion to a plastic base material such as a polycarbonate, A method for improving water resistance has been proposed, but if the water resistance is improved, other properties (hardness, scratch resistance, weather resistance, etc.) are affected, and sufficient adhesion and scratch resistance are obtained. And water resistance. Another problem is that it is difficult to copolymerize an acrylic monomer or the like with a monomer having an alkoxysilyl group. Moreover,
A method of imparting adhesiveness together with hardness, scratch resistance and water resistance by gradually changing the composite composition and performing multilayer coating has been proposed, but since the process becomes complicated, special applications are excluded. There are many problems in practical use.

In addition to the above, there has been proposed a composite product obtained by reacting a reaction product of an epoxy resin and an organosilicon compound with an organopolysiloxane obtained by hydrolyzing and condensing an organotrialkoxysilane (Patent Document 1). 280
No. 5942). However, although such a composite can improve the above problem to some extent, its abrasion resistance is not yet sufficient. Further, if an attempt is made to use tetrafunctional alkoxysilanes to improve the scratch resistance, the interaction with the epoxy resin is poor, so that the coating film is colored (whitened) or the adjustment liquid is separated into layers. There are various problems such as poor storage stability, and it has not been put to practical use.

[0009]

DISCLOSURE OF THE INVENTION The present invention provides excellent adhesion to a substrate, transparency, and the like without the need for a pretreatment such as a primer on the surface of a plastic material such as polycarbonate.
An object of the present invention is to provide a material capable of providing a coating film having excellent surface properties such as high hardness, scratch resistance, and water resistance.

[0010]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, the epoxy resin (2)
And a composition containing (a) tetraalkoxysilanes and (b) alkoxysilanes (1) containing aminosilane-containing alkoxysilanes, applied to the surface of a plastic tick, and heated and dried and cured. The coating film obtained by this method has a very good adhesion to the plastic surface without the need for a pretreatment such as a primer, and has excellent surface properties such as transparency, high hardness, scratch resistance, and water resistance. Was found to be able to be formed on a plastic surface, and the present invention was completed. Furthermore, they have found that the composition is non-aqueous and has excellent long-term storage stability.

That is, the present invention relates to an epoxy silane containing (a) a tetraalkoxy silane and (b) an alkoxy silane containing an amino group-containing alkoxy silane (1) and an epoxy resin containing an epoxy resin (2). Resin-
A composition for a silicon-based hybrid material; a composition for the epoxy resin-silicon-based hybrid material, which is a non-aqueous composition; a coating agent comprising the composition for the epoxy resin-silicon-based hybrid material; An epoxy resin-silicon hybrid material obtained by applying the coating agent to the surface of a plastic substrate, followed by curing by heating and drying to form a coating film on the surface of the plastic substrate. Coating method.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The alkoxysilanes (1) of the present invention comprise (a) tetraalkoxysilanes and (b) aminosilane-containing alkoxysilanes.

(A) As the tetraalkoxysilanes, for example, a compound represented by the general formula (1): Si (OR) ₄ (wherein
R represents a lower alkyl group. ) And / or partial hydrolysates thereof. Lower alkyl refers to a linear or branched alkyl group having about 1 to 7 carbon atoms. Specifically, a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group,
i-butyl group, sec-butyl group, t-butyl group, n-
Pentyl group, i-pentyl group, sec-pentyl group, n
-Hexyl group, i-hexyl group, sec-hexyl group,
Examples include a cyclopentyl group, a cyclohexyl group and a cycloheptyl group. (A) Specific examples of the tetraalkoxysilanes include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrai-propoxysilane, tetrabutoxysilane, tetrai-butoxysilane, and partially hydrolyzed condensates thereof. Can be

(B) Alkoxysila containing amino group
Examples of the compounds include those represented by the general formula (2): R¹ _lR² _m
Si (OR⁵)_n(Where R¹Is an amino group-containing
Alkyl group to R²Represents a lower alkyl group, R³Is a hydrogen atom
Or a lower alkyl group. l is an integer of 1-2, m is
An integer of 0 to 2, n represents an integer of 1 to 3, and l + m + n =
4 are satisfied. ) Organic represented by
A silicon compound and / or a partial hydrolyzate thereof
can give. The above R¹Al containing an amino group of
Examples of the kill group include a 3-aminoethyl group,
Aminopropyl group, 3-aminophenyl group, N- (2-
Aminoethyl) -3-aminopropyl group and the like.
You. R², R³Is the same as defined for R. Ma
R¹, R ², R³Are the same if there are multiple
But they may be different.

Specific examples of (2) amino-containing alkoxysilanes include, for example, 3-aminoethyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminophenyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminoethyltriethoxysilane, 3-aminopropyltriethoxysilane, 3-aminophenyltriethoxysilane, N- (2-aminoethyl) -3- Aminopropyltriethoxysilane, 3-aminoethylmethyldimethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminophenylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-amino Ethyl methyldiethoxy Orchid, 3-aminopropylmethyldiethoxysilane, 3-aminophenylmethyldiethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldiethoxysilane, 3-aminoethyldimethylmethoxysilane, 3-aminopropyl Examples include dimethylmethoxysilane, 3-aminophenyldimethylmethoxysilane, and N- (2-aminoethyl) -3-aminopropidimethylmethoxysilane.

The alkoxysilanes (1) of the present invention
Includes, in addition to the (a) tetraalkoxysilanes and (b) alkoxysilanes containing an amino group,
(C) Alkoxysilanes other than those described above can also be used.

(C) As other alkoxysilanes
Is, for example, the general formula (3): R⁴ _pSi (OR⁵)_q
(Where R⁴Is a functional group directly bonded to a carbon atom (however,
Lower alkyl group which may have
And an unsaturated aliphatic residue represented by R⁵Is a hydrogen atom or low
Represents a primary alkyl group. p is an integer of 1-3, q is 1-3
An integer satisfying p + q = 4 is shown. )
Organosilicon compounds and / or their partial hydrolysis
Things are given. Note that R⁴, R⁵Is the same as R in
R⁴The functional group directly bonded to the carbon atom of
Group, mercapto group, carboxyl group and the like. Also, R
⁴, R⁵Are the same or different when
May be.

Examples of R ⁴ (excluding lower alkyl groups) include vinyl, phenyl, toluyl, 3-chloropropyl, 3-glycidoxypropyl, 3-methacryloxypropyl, and 3-mercapto. And a propyl group and a 3,3,3-trifluoropropyl group.

Specific examples of the alkoxysilane (c) include methyltrimethoxysilane, ethyltrimethoxysilane, n-propyltrimethoxysilane, i-
Propyltrimethoxysilane, 3-chloropropyltrimethoxysilane, vinyltrimethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, n-propyltriethoxysilane, i-propyltriethoxysilane, 3-chloro Propyltriethoxysilane, vinyltriethoxysilane,
Phenyltriethoxysilane, methyltrii-propoxysilane, ethyltrii-propoxysilane, n-propyltrii-propoxysilane, i-propyltrii-propoxysilane, 3-chloropropyltrii-propoxysilane, vinyltrii-propoxysilane Phenyltri-i-propoxysilane, methyltributoxysilane, ethyltributoxysilane, n-propyltributoxysilane, i-propyltributoxysilane, 3-chloropropyltributoxysilane, vinyltributoxysilane, phenyltributoxysilane, 3,3,3-trifluorotrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3,4 Epoxycyclohexyl trimethoxysilane, 3,3,3-trifluoropropyl triethoxysilane, 3-methacryloxypropyl triethoxysilane, 3-glycidoxypropyl triethoxysilane, 3
-Mercaptopropyltriethoxysilane, 3,4-epoxycyclohexyltriethoxysilane, 3,3,3
-Trifluorotri-i-propoxysilane, 3-methacryloxypropyltri-i-propoxysilane, 3-glycidoxypropyltri-i-propoxysilane, 3-mercaptopropyltri-i-propoxysilane, 3,4-epoxycyclohexyltri-i- Propoxysilane, 3,
3,3-trifluorotributoxysilane, 3-methacryloxypropyltributoxysilane, 3-glycidoxypropyltributoxysilane, 3-mercaptopropyltributoxysilane, 3,4-epoxycyclohexyltributoxysilane, dimethyldimethoxysilane, Dimethyldiethoxysilane, diethyldimethoxysilane,
Examples thereof include diethyldiethoxysilane, diphenyldimethoxysilane, and diphenyldiethoxysilane. These can be used alone or in combination of two or more. Further, partially hydrolyzed condensates of these alkoxysilanes can be used.

The epoxy resin (2) of the present invention is not particularly limited as long as it has an epoxy functional group in the molecule.
Various known materials can be used. Specific examples of the epoxy resin include (hydrogenated) bisphenol A epoxy resin (commercially available, YD series manufactured by Toto Kasei Co., Ltd.),
Bisphenol F epoxy resin (commercially available, YDF series manufactured by Toto Kasei Co., Ltd.), phenol novolak type epoxy resin (commercially available, YDCN series manufactured by Toto Kasei Co., Ltd.), alkyl ether type epoxy resin (commercially available,
EX series manufactured by Nagase Kasei Kogyo Co., Ltd.). Further, those obtained by modifying these epoxy resins with an organic amine or the like in advance may be used. These epoxy resins can be used alone or in combination of two or more.

The epoxy resin-silicon hybrid material composition of the present invention comprises (a) a tetraalkoxysilane and (b) an alkoxysilane (1) containing an alkoxysilane containing an amino group, and an epoxy resin. (2) is contained. In such a composition, the alkoxysilane (b) containing an amino group mainly functions as a silane coupling agent, and improves the adhesion to a substrate due to the properties of the amino functional group. In addition, the amino functional group has a catalytic ability for alkoxysilanes (1). In addition, (2) the epoxy resin is applied to a coating film having the toughness, adhesion, and water resistance of the epoxy resin. The present invention focuses on the performance of (b) an alkoxysilane containing an amino group and (3) an epoxy resin, and by combining this with the (a) tetraalkoxysilanes, excellent thermosetting properties and ( b) Interaction between the amino group-containing alkoxysilane and (3) the amino group and the epoxy group of the epoxy resin has good complexability at the time of curing, and the coating film to be formed is a good coating film for the plastic substrate. Adhesion, high hardness,
Scratch resistance and water resistance are realized.

In the composition for an epoxy resin-silicon hybrid material of the present invention, the kind and the use ratio of each component are as follows:
The composition is appropriately adjusted according to the use to which the composition is to be provided.
The usage ratio (weight ratio) of the alkoxysilanes (1) and the epoxy resin (2) is usually (1) :( 2) = 90: 10.
It is preferable to set the range to about 10:90. Considering hard coating applications, (1): (2) = 9
0:10 to 50:50, and (1) :( 2) = 9
The ratio is more preferably 0:10 to 60:40. Also,
The amount of the epoxy resin (2) used is adjusted so that the amino groups of the (b) amino group-containing alkoxysilane imparting adhesion to the substrate are not completely consumed by the epoxy groups of the epoxy resin (2). Is preferred.

Also, in (1) alkoxysilanes,
(A) about 10 to 90% by weight of a tetraalkoxysilane, and (b) about 1% by weight of an alkoxysilane containing an amino group.
It is preferably used at about 0 to 90% by weight. (A) If the amount of the tetraalkoxysilane is less than 10% by weight, the hardness and scratch resistance as a coating film for a transparent plastic are not sufficient, and if the amount exceeds 90% by weight, the film is preferably cracked. Absent. (B) When the use amount of the amino group-containing alkoxysilane is less than 10% by weight, the interaction with the epoxy resin is insufficient, and the resulting coating film is colored (whitened), and the base plastic is Insufficient adhesion to If it is used in an amount exceeding 90% by weight, the amount of the (a) tetraalkoxysilane is relatively less than 10% by weight, and the hardness and scratch resistance are insufficient, which is not preferable.

In the present invention, (1) alkoxysilanes include, in order to control performance such as film forming property,
(C) Alkoxysilanes other than (a) and (b) can be used, but the upper limit of the amount used is about 80% by weight.
In order to realize sufficient hardness and abrasion resistance as a hard coating film of a transparent plastic, it is more preferably used at 60% by weight or less, more preferably at 50% by weight or less.

In the composition for an epoxy resin-silicon hybrid material of the present invention, the above (1) alkoxysilane and (2) the epoxy resin are usually stirred at about 20 to 100 ° C. for about 10 minutes to 5 hours, Prepare by mixing. The preparation method is not particularly limited, but at the time of preparation, first, (b) an alkoxysilane containing an amino group and (2) an epoxy resin are mixed and stirred, and when they become homogeneous, (a) tetraalkoxysilanes are added. It is preferred to add.

The preparation of the composition for an epoxy resin-silicon hybrid material is preferably carried out in a non-aqueous state, and the resulting composition is preferably a non-aqueous composition.

Usually, an organosiloxane composition using an alkoxysilane as a starting material uses a silica sol formed by a hydrolysis reaction after adding a predetermined amount of water to the alkoxysilane as a coating agent or the like. In this case, since the generated silanol is very reactive, the cross-linking reaction tends to proceed easily and gelation tends to occur easily, and there is a problem in long-term storage stability. Conventionally, in order to suppress the reaction of the silanol, such measures as adding an additive capable of forming a complex with the silanol have been devised, but the progress of the gelation reaction is still suppressed. It is difficult and also tends to require considerable energy and time for curing after application in order to suppress the curing reaction once. As described above, conventionally, organosiloxane-based compositions using alkoxysilane as a starting material usually have a problem in storage stability and the like of the composition since water is essentially required.

On the other hand, in the epoxy resin-silicon hybrid material composition of the present invention, (b) the amino group of the amino group-containing alkoxysilane itself is very effective for the silanol condensation reaction. Due to its high catalytic ability, curing proceeds even without a predetermined molar amount of water in the composition. That is, according to the composition of the present invention,
It can be a non-aqueous composition, and can have good storage stability. The composition of the present invention as a non-aqueous system is usually in a closed state, stored at room temperature for 60 days or more,
Does not cause gelation. The non-aqueous system referred to in the present invention refers to a state substantially free of water. Therefore, it is not prevented that a small amount of water is contained as a hardening accelerator so as not to promote gelation.

In the composition for an epoxy resin-silicon hybrid material of the present invention, various solvents can be used as needed. The solvent is not particularly limited as long as the composition of the present invention is in a solution state. For example, alcohols, ethers, ketones, esters, aromatic hydrocarbons, and nitrogen-containing solvents can be used. Specifically, methyl alcohol, ethyl alcohol, n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, i-butyl alcohol, sec-butyl alcohol, t-butyl alcohol, ethylene glycol,
Ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetrahydrofurfuryl alcohol, 1,4-dioxane, acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate Propyl acetate, butyl acetate, propylene carbonate, ethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether acetate, toluene, xylene, dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone and the like. These solvents can be used alone or in combination of two or more.

When the composition for an epoxy resin-silicon hybrid material of the present invention is used as a coating agent for a plastic substrate, the solvent may be methyl alcohol, ethyl, or the like in consideration of the influence on the plastic substrate. It is preferable to use alcohol, i-propyl alcohol, n-butyl alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl ethyl ketone, methyl isobutyl ketone, N-methyl-2-pyrrolidone and the like.

In the composition for an epoxy resin-silicon hybrid material of the present invention, (b) an alkoxysilane containing an amino group also functions as a curing accelerator. In order to raise the viscosity, a curing accelerator may be separately used. Specific examples of the curing accelerator include alcoholic potassium hydroxide, alcoholic sodium hydroxide, ethylamine, diethylamine, triethylamine, ethylenediamine, diethylenetriamine,
Β-diketone complexes such as ethanolamine, diethanolamine, triethanolamine, dimethylethanolamine, Al (III) triacetylacetone complex, and organotin compounds such as dibutyltin octylate can be used.

The amount of the curing accelerator used can be appropriately determined depending on the type of the accelerator used, but usually, (1)
A total of 1 alkoxysilanes and (2) epoxy resin
It is preferable that the amount is at most about 10 parts by weight with respect to 00 parts by weight. If it is used in excess of 10 parts by weight, the influence on properties such as film forming properties and transparency of the coating film is undesirably increased. These curing accelerators can be used alone or in combination of two or more, depending on the organosilicon compound used, the physical properties of the intended coating film, and the like. The timing of addition of the curing accelerator is not particularly limited, and may be added to the composition of the present invention in advance, or may be added immediately before coating the composition on a substrate.

The epoxy resin-silicon hybrid material composition of the present invention contains a viscosity modifier, a leveling agent, an antifoaming agent, a coloring agent, a stabilizer, a solubility, as long as the effects of the present invention are not impaired. Various organic and inorganic additives such as a solvent for adjusting the solid content can also be added as necessary.

The composition for an epoxy resin-silicon hybrid material of the present invention is used, for example, as a coating agent.

The coating agent applied to the surface of the plastic substrate has good wettability and adhesion, and is excellent in coating workability. Further, the coating agent applied to the surface of the plastic base material is heated and dried to (1) the alcohol silane / polycondensation of the alkoxysilane rapidly and hardens to form a coating film having a three-dimensional siloxane bond on the plastic surface. . As a coating method of the coating agent, various ordinary coating methods such as dip coating, roll coating, bar coating, curtain flow coating, spray coating, and spin coating can be employed.

As the plastic used as the substrate of the coating agent of the present invention, various materials and forms can be used. Among them, the coating film is excellent in transparency, so that it is suitable for the surface coating of transparent plastic. is there. Examples of the transparent plastic include polymethyl methacrylate, polycarbonate, polyethylene terephthalate, and the like.

The curing temperature is equal to or lower than the deformation temperature of the plastic substrate used, and is usually about 20 to 300 ° C.
When the base material is polycarbonate, it is preferable to perform the curing at 130 ° C. or lower. Although the curing time varies depending on the composition of the coating agent, heat drying and curing are performed for about 3 minutes to 24 hours, more preferably 5 minutes to 120 minutes.

The thickness of the coating film formed on the surface of the plastic substrate is usually about 1 to 50 μm in a single application. Since the coating agent of the present invention can be applied repeatedly and has good adhesion, a coating film having an arbitrary thickness can be formed. In addition, it is also possible to apply various color hues by blending a coloring agent.

[0039]

According to the present invention, it is possible to provide a composition having excellent adhesion to various plastic substrates, particularly to a transparent plastic substrate such as polycarbonate. Therefore, it is possible to improve productivity and reduce costs without the need for pretreatment such as primers. Further, the composition of the present invention can be used as a non-aqueous composition, and thus has excellent long-term storage stability.

The composition of the present invention is useful as a coating agent and the like, and can provide a coating film with high hardness on the surface of plastic. The surface hardness of the coating film of the obtained surface-modified plastic is usually H or higher in pencil hardness, and a level of no scratch can be achieved with steel wool No. 000.

Further, the scratch resistance, abrasion resistance, weather resistance, water resistance, chemical resistance, heat resistance, etc. of the plastic surface can be remarkably improved and improved. For example, transparent plastics such as polycarbonate are often susceptible to being damaged by the organic solvent, and the transparency is often impaired.However, the coating film formed by the coating agent of the present invention has significantly improved solvent resistance, and various organic solvents, for example, Rubbing with a cloth containing a ketone solvent such as methyl ethyl ketone, an aromatic solvent such as toluene, or an aliphatic solvent such as hexane or cyclohexane does not impair the transparency.

Regarding the water resistance, even if the coating film formed by the coating agent of the present invention is immersed in, for example, hot water heated to 80 ° C. for 5 hours or more, no crack is generated and the appearance is impaired. There is no.

[0043]

EXAMPLES Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. In addition, the characteristic evaluation in an Example was performed using the following method.

"Hardness (Empitz hardness)": JIS-K5
400.

"Scratch resistance": The coating film was rubbed 15 times with a load of 500 g using # 000 steel wool. Evaluation was performed based on the following criteria. ：: Almost no damage ×: Damage or fogging

"Adhesion (cross-cut test)": 100 (10.times.10) squares of 1 mm square reaching the plastic substrate were cut into the coating with a steel knife, and cellophane tape (Nichiban Co., Ltd.) was applied. After pressure bonding, the film was rapidly peeled off in the direction of 90 ° C., and the degree of peeling of the coating film was evaluated. 100/100: no peeling. 0/100: All peeled.

"Appearance of coating film": Evaluation was made visually. ：: colorless and transparent, uniform Δ: translucent, slightly cloudy X: No transparency.

"Chemical resistance": The coating film surface was rubbed with a cloth impregnated with xylene, and left at room temperature for 15 minutes. ：: No change in the coating film. ×: The coating film is whitened, dissolved or peeled.

"Water resistance": The coated substrate is
The film was left immersed in hot water at 80 ° C. for 5 hours, and the appearance change of the coating film was evaluated. ：: No change in coating film ×: Changes in film such as cracks, peeling and coloring

"Storage stability": The prepared composition was allowed to stand at room temperature in a closed state, and the appearance change after one month was observed according to the following criteria. After leaving for one month, the same evaluation as described above was performed to confirm a change in characteristics. (Appearance of the composition after one month) 均一: Uniform, colorless and transparent ×: Changes such as gelation, solid sedimentation, coloring, and increase in viscosity

Example 1 Erlenmeyer flask with a stopcock containing a stirrer (300 ml)
Then, 25 g of 3-aminopropyltriethoxysilane and 25 g of a glycidyl ether type epoxy resin (EX-314 manufactured by Nagase Kasei Kogyo Co., Ltd.) were added and stirred and mixed at room temperature for 1 hour. Next, after adding 80 g of methanol and mixing uniformly, 50 g of tetramethoxysilane was added with stirring at room temperature. After completion of the addition, the mixture was stirred and mixed at room temperature for 2 hours to prepare a colorless, transparent and uniform composition for an epoxy resin-silicon hybrid material.

Examples 2 to 8 and Comparative Example 3 In Example 1, alkoxysilane, epoxy resin,
An epoxy resin-silicon hybrid material composition was prepared in the same manner as in Example 1 except that the type and / or amount of the solvent was changed as shown in Table 1.

Comparative Example 1 4 g of tetramethoxysilane and 1 g of methyltrimethoxysilane were placed in a 100 ml reaction vessel equipped with a reflux condenser and a stirrer.
6 g, water 10 g, ethyl alcohol 20 g, acetic acid 0.2
g was added and mixed under stirring at 70 ° C. for 2 hours to prepare a colorless, transparent and uniform alkoxysilane composition.

Comparative Example 2 A 100 ml reaction vessel equipped with a reflux condenser and a stirrer was charged with 20 g of methyltrimethoxysilane, 10 g of water and 0.2 g of acetic acid.
g was added and stirred and mixed at 70 ° C. for 5 hours. Then, the alcohol and water generated under reduced pressure were distilled off, and 20 g of isopropyl alcohol was added to prepare a transparent and uniform alkoxysilane composition.

Comparative Example 4 In Example 1, no tetramethoxysilane was used.
A composition for an epoxy resin-silicon hybrid material was prepared in the same manner as in Example 1 except that the types and / or amounts of the other alkoxysilanes, epoxy resins, and solvents were changed as shown in Table 1.

Comparative Example 5 In Example 1, without using 3-aminopropyltriethoxysilane, the types and / or amounts of other alkoxysilanes, epoxy resins and solvents were changed as shown in Table 1, and the catalyst was used as a catalyst. An epoxy resin-silicon hybrid material composition was prepared in the same manner as in Example 1 except that 10 g of dimethylethanolamine was used.

[0057]

[Table 1]

In Table 1, TMOS: tetramethoxysilane, MTMOS: methyltrimethoxysilane, MS-5
1: Partial hydrolysis condensation product of tetramethoxysilane (M silicate 51, manufactured by Tama Chemical Industry Co., Ltd.), 3APTES
i: 3-aminopropyltriethoxysilane, 3APT
MSi: 3-aminopropyltrimethoxysilane, NA
EAPTMSi: N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, EX-314: Glucidyl ether type epoxy resin (manufactured by Nagase Kasei Kogyo Co., Ltd.) YD-014: Bisphenol A type epoxy resin (Toto Kasei Co., Ltd.) MeOH: methyl alcohol, EtOH: ethyl alcohol, IPA: i-propyl alcohol, MC: ethylene glycol monomethyl ether, DMEA: dimethylethanolamine.

The compositions obtained in the above Examples and Comparative Examples were used as coating agents in the following practical examples.

(Practical example) A polycarbonate sheet (hereinafter referred to as PC sheet; manufactured by Nippon GE Plastics Co., Ltd.)
Yoshimitsu Seiki Co., Ltd. on a test piece from which a protective film (Lexan: 0.5 mm thick with a double-sided protective film) was peeled off.
After coating using a YBA type applicator (coating gap: 50 micrometers), heating and drying were performed at 110 ° C. for 30 minutes. The above-mentioned evaluation was performed about the obtained coating film. Table 2 shows the results.

[0061]

[Table 2]

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) C09D 163/00 C09D 163/00 183/02 183/02 F term (reference) 4F006 AA22 AA35 AA36 AB34 AB67 BA02 CA05 DA04 EA05 4J002 CD011 CD051 CD061 CD201 EX036 EX076 FD146 GH02 4J036 AA01 DD08 GA28 JA01 4J038 DB061 DB062 DB071 DB072 DL021 DL022 DL031 DL032 DL081 DL082 JC32 JC35 NA04 NA11 NA12 PB06 PB08 PC08

Claims (7)

[Claims] 1. An epoxy resin-silicon containing (a) a tetraalkoxysilane and (b) an alkoxysilane (1) containing an aminosilane-containing alkoxysilane and an epoxy resin (2). A composition for a hybrid material. 2. An organosilicon compound represented by the general formula (1): Si (OR) ₄ (where R represents a lower alkyl group) and / or a tetraalkoxysilane (a). The composition for an epoxy resin-silicon hybrid material according to claim 1, which is a partial hydrolyzate. Wherein (b) alkoxysilanes having an amino group, the general formula ^{_{(2): R 1 l R}} 2 m Si (OR 3)
_n (wherein R ¹ represents an alkyl group containing an amino group;
² represents a lower alkyl group, and R ³ represents a hydrogen atom or a lower alkyl group. l is an integer of 1-2, m is an integer of 0-2,
n shows the integer of 1-3, and shows what satisfies l + m + n = 4. 3. The composition for an epoxy resin-silicon hybrid material according to claim 1, which is an organosilicon compound represented by the formula (1) and / or a partial hydrolyzate thereof. 4. The composition for an epoxy resin-silicon hybrid material according to claim 1, which is a non-aqueous composition. 5. A coating agent comprising the composition for an epoxy resin-silicon hybrid material according to claim 1. 6. An epoxy resin-silicon hybrid material obtained by curing the composition according to claim 1 by heating and drying. 7. A method of coating a plastic surface, comprising applying the coating agent according to claim 5 to the surface of a plastic substrate, curing the material by heating and drying, and forming a coating film on the surface of the plastic substrate.