JPH0365382B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention provides a coating with excellent abrasion resistance, which is obtained by coating a polycarbonate resin base material with an undercoat paint that has good adhesion to the polycarbonate resin and curing it, and then coating and curing a topcoat paint containing a silicon resin. This invention relates to polycarbonate resin molded articles. Generally, polycarbonate resin has impact resistance,
Due to its excellent transparency, it is widely used as a transparent plastic material, but it has the drawbacks of poor abrasion resistance and solvent resistance, the surface is easily scratched, and it is easily attacked by organic solvents. Various methods of coating with thermosetting resin have been proposed as methods to improve these drawbacks, but at present none of them is fully satisfactory. For example, trialkoxysilanes such as methyltrialkoxysilane and phenyltrialkoxysilane, combinations of these with tetraalkoxysilanes such as ethylsilicate and butylsilicate, or mixtures with other resin paints are known. It has not been possible to obtain a coating that has good physical properties such as abrasion resistance, hot water resistance, heat resistance, adhesion, and paint pot life. In addition, the special public official court Sho 53-15743,
53-35589, epoxy group-containing alkoxysilanes, Lewis acids such as BF ₃ , BF ₃ etherate, or their complexes, HCl, HBr, HI, HNO ₃ , HClO ₄ ,
Articles coated with and cured coating compositions containing curing catalysts such as metal salts of Brønsted acid, cobalt naphthenate, zinc naphthenate, and other organic acids such as H ₃ PO ₄ have been disclosed. It has a short pot life or takes a long time to harden, making it impractical. Furthermore, the adhesion to polycarbonate base materials is poor. Japanese Patent Publication No. 52-39691 discloses a coating composition containing a hydrolyzate of colloidal silica and methyltrimethoxysilane as main components, and this cured coating film has sufficient hardness but is not flexible. Furthermore, it is extremely difficult to obtain good adhesion to plastic substrates.
JP-A-53-111336 describes one or more compounds selected from compounds containing epoxy groups and/or silanol and/or siloxane groups, silica fine particles of 1 to 100 millimicrons, and aluminum chelate compounds. However, these cured coatings have insufficient hardness, resulting in a decrease in hardness when immersed in boiling water, etc., and also have poor adhesion to bisphenol type polycarbonate. In addition, Japanese Patent Application Publication No. 55-500856 and No. 55-500858 disclose polycarbonate articles having a thermoplastic acrylic polymer as an undercoat layer and a heat-cured colloidal silica-filled organopolysiloxane as an overcoat layer, but these are very Adhesion, hot water resistance,
Weather resistance etc. are not fully satisfactory. The present inventors aimed to eliminate such drawbacks and provide polycarbonate resin molded articles with improved abrasion resistance, solvent resistance, chemical resistance, and weather resistance.As a result of extensive research, the present inventors found that polycarbonate An undercoat layer is applied by applying and baking an undercoat paint containing an acrylic or vinyl copolymer having an alkoxysilyl group in the side chain and a curing catalyst to the resin base material, and the top coat layer is attached to the polycarbonate resin base material. Furthermore, a top coat containing an organopolysiloxane containing colloidal silica is applied on the undercoat layer and baked to improve the abrasion resistance and solvent resistance of polycarbonate resin molded articles. It has been found that properties such as durability, chemical resistance and weather resistance can be improved. That is, the present invention comprises (a) a copolymer of an acrylic or/and vinyl monomer having an alkoxysilyl group and another monomer copolymerizable with these monomers, and (b) a curing catalyst. The present invention provides a coated polycarbonate resin molded article having improved abrasion resistance, in which a composition containing a colloidal silica-containing organopolysiloxane is coated and cured to form an undercoat layer, and a composition containing a colloidal silica-containing organopolysiloxane is coated and cured to form a topcoat layer. be. In the present invention, a composition containing an organopolysiloxane containing colloidal silica used as a top coat means at least one member selected from the group consisting of (A) and (B) below, (C) and (D), (A ) General formula (1)

[Formula] (In the formula, R ¹ is an organic group having an epoxy group, R ²
is hydrogen, a hydrocarbon group having 1 to 6 carbon atoms, R ³ is a hydrocarbon group having 1 to 5 carbon atoms, an alkoxyalkyl group, or an acyl group having 1 to 4 carbon atoms, and a is 1 to 4 carbon atoms.
3, b is 0 to 2, and a+b≦3. ) One or more hydrolysates selected from silicon compounds having an epoxy group represented by (B) General formula (2) R ⁴ _c -Si-(OR ⁵ ) _4-c (2) (in the formula R ⁴ is a hydrocarbon group having 1 to 6 carbon atoms, a methacryloxy group, an amino group, a mercapto group, an organic group having fluorine or chlorine, and R ⁵ is a hydrocarbon group having 1 to 5 carbon atoms, an alkoxyalkyl group, or an alkoxyalkyl group having 1 to 5 carbon atoms. 1 to 4 acyl groups, and c is 0 to 3.) (C) Colloidal silica (D) A composition containing a curing catalyst, preferably (A) General 100 parts by weight of one or more hydrolysates selected from silicon compounds having epoxy groups represented by formula (1) (calculated on solid content,

Calculate as [Formula]. ) (B) 56 to 550 parts by weight of a hydrolyzate of an organosilicon compound represented by general formula (2) (calculated on solid content,
Calculated as R ⁴ _c -Si-O4-c/2. ) (C) 4 to 334 parts by weight of colloidal silica (calculated based on solid content and calculated as SiO ₂ )
The sum of (B) and (C) does not exceed 567 parts by weight, preferably from 60 to 567 parts by weight. and (D) a composition comprising a curing catalyst. More preferably, with respect to 100 parts by weight of component (A), component (B) is 105 to 430 parts by weight, component (C) is 16 to 200 parts by weight, and the total of component (B) and component (C) is 121 to 430 parts by weight. It is 473 parts by weight. If the total amount of component (B) and component (C) is less than 60 parts by weight, the effect of using them together will be reduced, and if it exceeds 567 parts by weight, the flexibility of the cured coating will be significantly reduced.
Furthermore, it becomes extremely difficult to obtain good adhesion. Component (A) represented by general formula (1) used in the present invention
Examples of the silicon compound having an epoxy group include the following. Specific examples of silicon compounds having one glycidoxy group include glycidoxymethyltrimethoxysilane glycidoxymethyltriethoxysilane β-glycidoxyethyltrimethoxysilane β-glycidoxyethyltriethoxysilane γ-glycid Xypropyltrimethoxysilane γ-Glycidoxypropyltriethoxysilane γ-Glycidoxypropyltri(methoxyethoxy)silane γ-Glycidoxypropyltriacetoxysilane δ-Glycidoxybutyltrimethoxysilane δ-Glycidoxybutyl Triethoxysilane Glycidoxymethyldimethoxysilane Glycidoxymethyl(methyl)dimethoxysilane Glycidoxymethyl(ethyl)dimethoxysilane Glycidoxymethyl(phenyl)dimethoxysilane Glycidoxymethyl(vinyl)dimethoxysilane Glycidoxymethyl( dimethyl)methoxysilane β-glycidoxyethyl(methyl)dimethoxysilane β-glycidoxyethyl(ethyl)dimethoxysilane β-glycidoxyethyl(dimethyl)methoxysilane γ-glycidoxypropyl(methyl)dimethoxysilane γ- Glycidoxypropyl (ethyl) dimethoxysilane γ-glycidoxypropyl (dimethyl) methoxysilane δ-glycidoxybutyl (methyl) dimethoxysilane δ-glycidoxybutyl (ethyl) dimethoxysilane δ-glycidoxybutyl (dimethyl ) Methoxysilane Specific examples of silicon compounds having two or three glycidoxy groups include: bis(glycidoxymethyl)dimethoxysilane bis(glycidoxymethyl)diethoxysilane bis(glycidoxyethyl)dimethoxysilane bis( Glycidoxyethyl)diethoxysilane Bis(glycidoxypropyl)dimethoxysilane Bis(glycidoxypropyl)diethoxysilane Tris(glycidoxymethyl)methoxysilane Tris(glycidoxymethyl)ethoxysilane Tris(glycidoxypropyl)diethoxysilane Ethyl)methoxysilane Tris(glycidoxyethyl)ethoxysilane Tris(glycidoxypropyl)methoxysilane Tris(glycidoxypropyl)ethoxysilane Specific examples of silicon compounds having glycidyl groups include: glycidylmethyltrimethoxysilane glycidylmethyl Triethoxysilane β-glycidylethyltrimethoxysilane β-glycidylethyltriethoxysilane γ-glycidylpropyltrimethoxysilane γ-glycidylpropyltriethoxysilane γ-glycidylpropyltri(methoxyethoxy)silane γ-glycidylpropyltriacetoxysilane Alicyclic Specific examples of silicon compounds having the formula epoxy group include: 3,4-epoxycyclohexylmethyltrimethoxysilane 3,4-epoxycyclohexylmethyltriethoxysilane 3,4-epoxycyclohexylethyltrimethoxysilane 3,4-epoxycyclohexylpropyl Trimethoxysilane 3,4-epoxycyclohexylbutyltrimethoxysilane may be mentioned. The above general formula (2) which is the component (B) used in the present invention
Examples of the organosilicon compound represented by include the following. That is, trimethylmethoxysilane, dimethyldimethoxysilane, methyltrimethoxysilane, tetraethoxysilane, phenyltrimethoxysilane, phenylmethyldimethoxysilane, vinyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, vinyltriacetoxysilane, γ
- methacryloxypropyltrimethoxysilane,
γ-aminopropyltriethoxysilane, N-
(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-bis(β-hydroxyethyl)-γ-aminopropyltriethoxysilane,
Examples include N-(β-aminoethyl)-γ-aminopropyl(methyl)dimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, etc. . These may be used alone or in combination of two or more. The colloidal silica of component (C) is a colloidal solution in which ultrafine particles of silicic anhydride, preferably having a particle size of 1 to 100 millimicrons, are dispersed in a dispersion medium, such as water or an alcohol-based dispersion medium, using a well-known method. It is manufactured and commercially available. By using these components (B) and (C) in combination with component (A), the weather resistance of the coating film is improved, and the appearance and hardness after a weather resistance test are improved. In the present invention, one or more hydrolysates selected from the silicon compounds having an epoxy group represented by the general formula (1) used as the component (A) and the general formula ( The hydrolyzate of one or more selected from the organosilicon compounds shown in 2) is one in which a part or all of the alkoxy group, alkoxyalkoxy group, or acyloxy group in the silicon compound is substituted with a hydroxyl group. and some naturally condensed substituted hydroxyl groups. These hydrolysates can be obtained by hydrolysis in a mixed solvent such as water and alcohol in the presence of an acid, as is known in the art. When the silicon compounds represented by the general formulas (1) and (2) are used without being hydrolyzed, the cured coating film becomes white and the abrasion resistance is insufficient. When using the silicon compounds represented by the general formulas (1) and (2) as a hydrolyzate, better results are often obtained by mixing them and simultaneously cohydrolyzing them than by hydrolyzing them separately. As the curing catalyst for component (D) in the coating composition for the top coat layer in the present invention, the following catalysts can be used. i.e. ammonium perchlorate, ammonium nitrate, ammonium chloride,
ammonium sulfate, ammonium thiocyanate,
Perchloric acid, hydrochloric acid, nitric acid, phosphoric acid, sulfuric acid, sulfonic acid, para-toluenesulfonic acid, boron trifluoride and its complexes with electron donors. SnCl ₄ , ZnCl ₃ ,
Lewis acids such as FeCl ₃ , AlCl ₃ , SbCl ₅ , TiCl ₄ and their complexes. Organic acid metal salts such as sodium acetate, zinc naphthenate, cobalt naphthenate, zinc octylate, and tin octylate. Boufurated metal salts such as zinc borofluoride and tin borofluoride. Boric acid organic esters such as ethyl borate and methyl borate. Alkali such as sodium hydroxide and potassium hydroxide. Titanate esters such as tetrabutoxytitanium and tetraisopropoxytitanium. Metal acetylacetonates such as chromium acetylacetonate, titanyl acetylacetonate, aluminum acetylacetonate, cobalt acetylacetonate, and nickel acetylacetonate. Amines such as n-butylamine, di-n-butylamine, tri-n-butylamine, guanidine, biguanide, and imidazole; high-base compounds such as ammonium trifluoromethylsulfonate, sodium trifluoromethylsulfonate, and potassium trifluoromethylsulfonate; aliphatic sulfonate, _NH4
(CF ₃ SO ₂ ) ₂ C.Br, K (CF ₃ SO ₂ ) ₂ CH, Ba
Examples include highly fluorinated aliphatic sulfonyl compounds such as [(CF ₃ SO ₂ ) ₂ CH] ₂ and the like. Among these curing catalysts, ammonium perchlorate, ammonium chloride, ammonium sulfate, ammonium nitrate, sodium acetate, and trifluoromethylsulfonic acid have good hardness and transparency of the coating film, and have a long pot life of the coating solution. Perchlorates, hydrochlorides, sulfates, carboxylates, highly fluorinated aliphatic sulfonates, and highly fluorinated aliphatic sulfonyl compounds such as ammonium and bis(trifluoromethylsulfonyl)bromomethylammonium are suitable. ing. As the curing catalyst contained in the top coating composition of the present invention, one or two or more of the above-mentioned various curing catalysts may be used in combination. The amount of these curing catalysts added is 0.05 to 10 parts by weight, more preferably 0.1 to 5 parts by weight, based on the solid content of the top coating composition. Solvents that may be included in the topcoat composition include:
Examples include alcohols, ketones, esters, ethers, cellosolves, halides, carboxylic acids, aromatic compounds, etc., and one or more of these can be used as a mixed solvent. In particular, lower alcohols such as methanol, ethanol, propanol, isopropanol, butanol, cellosolves such as methyl cellosolve, ethyl cellosolve, and butyl cellosolve; lower alkyl carboxylic acids such as formic acid, acetic acid, and propionic acid; aromatic compounds such as toluene and xylene; acetic acid Esters such as ethyl and butyl acetate;
It is preferable to use ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone alone or as a mixed solvent. Further, if necessary, a flow control agent such as a fluorine surfactant or a block copolymer of alkylene oxide and dimethylsiloxane may be added to obtain a smooth coating film. The amount of these flow control agents added is sufficient in a small amount, and is 0.01 to 5% by weight, more preferably 0.03 to 3 parts by weight, based on the entire topcoat composition. Further, small amounts of antioxidants, ultraviolet absorbers, etc. can also be added. Coating with top coat paint is done by the commonly used dipping method, spraying method, roller coating method,
Or, use a coating method such as the flow coating method to coat a polycarbonate base material that has been previously coated with the top coat described below and baked at 70°C.
By baking and curing the above coating at a temperature below the deformation temperature of the base material (for example, 130° C.) for 20 minutes to 5 hours, a coating film with good wear resistance, adhesion, hot water resistance, and weather resistance can be obtained. The preferred thickness of this top coat is 1 to 30 microns, more preferably 3 to 15 microns. 1
If it is less than 30 microns, the wear resistance will not be sufficient, and if it is more than 30 microns, cracks will easily occur. In the present invention, a copolymer of an acrylic or vinyl monomer having an alkoxysilyl group used as an undercoat and another monomer copolymerizable therewith has a general formula (In the formula, R ⁶ is hydrogen or methyl group, R ⁷ has 1 carbon number
-6 hydrocarbon group, ^R8 is a C1-C5 hydrocarbon group, an alkoxyalkyl group, or a C1-4 acyl group, and d is 0, 1 or 2. R ⁸ may be the same group or a mixture of different groups. ) or/and general formula (In the formula, R ⁹ is a hydrocarbon group having 1 to 6 carbon atoms, R ¹⁰ is a hydrocarbon group having 1 to 5 carbon atoms, an alkoxyalkyl group, or an acyl group having 1 to 4 carbon atoms, and e is 0, 1 or 2. R ¹⁰ may be the same group or a mixture of different groups.) It is a copolymer having a structure represented by general formula (3) or/and general formula (4) (In the formula, R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , d and e
has the meaning given above. It can be obtained by addition polymerizing the monomers shown in ) and other monomers copolymerizable with these monomers. If R ⁸ and R ¹⁰ are a mixture of different groups, a copolymer may be obtained by polymerizing monomers having different groups, or a copolymer may be obtained by polymerizing monomers having the same group. It can also be obtained by obtaining a polymer and then transesterifying it in the presence of an alcohol. In the acrylic monomer having an alkoxysilyl group represented by the general formula (3), R ⁷ in the general formula is, for example, an alkyl group such as methyl, ethyl, propyl, butyl; an aryl group such as phenyl; vinyl, allyl, etc. Examples of R ⁸ include alkyl groups such as methyl, ethyl, propyl, and butyl; alkoxyalkyl groups such as methoxyethoxy, ethoxyethoxy, and butoxyethoxy; and acyl groups such as ^acetyl ; Various compounds can be used in the present invention depending on the types of ⁷ and R ⁸ and the number of d, and specific examples include the following. γ-
(meth)acryloxypropyltrimethoxysilane, γ-(meth)acryloxypropyltriethoxysilane, γ-(meth)acryloxypropylmethyldimethoxysilane, γ-(meth)acryloxypropylmethyldiethoxysilane, γ-( These include meth)acryloxypropyldimethylmethoxysilane, γ-(meth)acryloxypropyldimethylethoxysilane, and the like. In the vinyl monomer having an alkoxysilyl group represented by the general formula (4), R ₉ in the general formula may be the same group as R ⁷ , R ¹⁰ may be the same group as R ⁸ , Various compounds are used in the present invention depending on the types of R ⁹ and R ¹⁰ and the number of e, but
Specific examples include the following. Examples include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, vinyltriacetoxysilane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, vinyldimethylmethoxysilane, and vinyldimethylethoxysilane. Other monomers copolymerizable with the monomers represented by general formulas (3) and (4) include the following. Methyl (meth)acrylate, Ethyl (meth)acrylate, Propyl (meth)acrylate, (Meth)
Butyl acrylate, 2-ethylhexyl (meth)acrylate, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, butylene glycol mono(meth)acrylate, glycerol mono(meth)acrylate, polyethylene glycol mono(meth)acrylate, Polypropylene glycol mono(meth)acrylate, glycidyl(meth)acrylate, dimethylaminoethyl(meth)acrylate, diethylaminoethyl(meth)acrylate, dibutylaminoethyl(meth)acrylate, dimethylaminopropyl(meth)acrylate, diethylaminopropyl(meth)acrylate Acrylate, dibutylaminopropyl (meth)acrylate, (meth)
Acrylamide, methylol(meth)acrylamide, butoxymethyl(meth)acrylamide,
(meth)acrylic acid, crotonic acid, maleic acid,
Itaconic acid, styrene, vinyltoluene, vinyl acetate, acrylonitrile, allyl alcohol, etc., but any monomer that can be copolymerized with the monomers represented by general formulas (3) and (4) It may be. The monomers represented by general formulas (3) and (4) are contained in the copolymer obtained by polymerizing them in an amount of 1 to 70% by weight, preferably 2 to 40% by weight, and more preferably 2 to 30% by weight. It will be done. If it is less than 1% by weight, the adhesion between the undercoat film and the topcoat film containing colloidal silica-containing organopolysiloxane will decrease, and if it is more than 70% by weight, the adhesion of the undercoat film to the polycarbonate resin substrate will decrease. The stability of the coating liquid also decreases. The weight average molecular weight of the copolymer is from 10,000 to 300,000, preferably from 20,000 to 200,000. If it is less than 10,000, the adhesion to the polycarbonate resin substrate will decrease, and if it is more than 300,000, the appearance of the coating film will be impaired, which is not preferable. The curing catalyst used in the undercoating paint of the present invention includes inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, and perchloric acid. Organic acids such as formic acid, acetic acid, propionic acid, para-toluenesulfonic acid, and oxalic acid. Organic acid metal salts such as zinc naphthenate, cobalt naphthenate, lead naphthenate, zinc octylate, and tin octylate. n-butylamine, di-n-butylamine,
Amines such as diethanolamine, 3-trimethoxysilylpropylamine, and imidazoles. Boron trifluoride and its complex with an electron donor. Boric acid organic esters such as methyl borate and ethyl borate. Organic titanates such as tetra-n-butoxytitanium and its oligomers, tetraisopropoxytitanium and its oligomers, diisopropoxybis(acetylacetonate)titanium, di-n-butoxybis(triethanolaminate)titanium. _SnCl4 , _ZnCl3 , _FeCl3 , _AlCl3 , _SbCl5 ,
Lewis acids such as TiCl ₄ and their complexes. Bicyclic amidines such as 1,5-diazabicyclo(4,3,0)nonene-5, 1,8-diazabicyclo(5,4,0)undecene-7 and salts thereof. Organic tin compounds such as dibutyltin dilaurate and dibutyltin maleate. Quaternary ammonium salts such as tetramethylammonium chloride and triethylbenzylammonium bromide. Examples include metal acetylacetonates such as chromium acetylacetonate, titanyl acetylacetonate, aluminum acetylacetonate, cobalt acetylacetonate, and nickel acetylacetonate. Among these curing catalysts, organic acids, amines, metal acetylacetonates, and organic titanates are cited as catalysts that have particularly good adhesion of the coating film to the polycarbonate resin base material and have a long pot life of the coating liquid. I can do it. The various curing catalysts mentioned above may be used alone or in combination of two or more. The amount of the curing catalyst added is 0.01 to 10% by weight, preferably 0.1 to 5% by weight, based on the copolymer. If it is less than 0.01% by weight, no effect as a curing catalyst will be recognized, and if it is more than 10% by weight, the stability of the coating liquid will decrease. In order to obtain an undercoat paint, in addition to the above-mentioned components, a solvent and various additives are added as desired. Examples of solvents include alcohols such as methanol, ethanol, isopropanol, butanol, and diacetone alcohol; cellosolves such as methyl cellosolve, ethyl cellosolve, isopropyl cellosolve, and butyl cellosolve; ethyl acetate,
Butyl acetate, ethylene glycol diacetate,
Examples include acetic acid esters such as ethyl cellosolve acetate; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and diisopropyl ketone; and carboxylic acids such as formic acid, acetic acid, and propionic acid, and a mixture of these may be used. Examples of additives include flow control agents, ultraviolet absorbers, ultraviolet stabilizers, and antioxidants. Examples of flow control agents include commercially available fluorine-based surfactants and block copolymers of alkylene oxide and dimethylsiloxane.
0 to 5% by weight in the undercoat composition, more preferably 0
~3% by weight. As a UV absorber, 2-hydroxy-4-
Methoxybenzophenone, 2-hydroxy-4-
Octoxybenzophenone, 2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4-
Benzophenones such as methoxybenzophenone; 2-(2'-hydroxy-5'-methylphenyl)
Benzotriazole, 2-(2'-hydroxy-
5'-t-butylphenyl)benzotriazole,
2-(2'-hydroxy-5'-octylphenyl)
Benzotriazole, 2-(2'-hydroxy-3',
Benzotriazoles such as 5'-di-t-butylphenyl)benzotriazole, 2-(2'-hydroxy-di-t-butylphenyl)-5-chlorobenzotriazole; ethyl-2-cyano-3,
Examples include cyanoacrylates such as 3'-diphenyl acrylate, which are used in an amount of 1 to 200 parts by weight per 100 parts by weight of the acrylic copolymer or vinyl copolymer in the undercoat composition. An undercoat film is obtained by applying an undercoat composition comprising the above-mentioned components to the surface of a polycarbonate resin molded article and baking the resulting coating film at a temperature lower than the heat distortion temperature of the resin molded article. Baking is done at 70-130℃ for 20 minutes to 5 hours.
In this case, if the top coat is applied after the undercoat has been completely cured by baking, the adhesion between the undercoat and top coat may tend to decrease. Therefore, it is more preferable to select baking conditions so that curing of the undercoat film is completed at the time of baking after application of the topcoat. The method for applying the undercoat of the present invention includes the commonly used dipping method, spraying method, roller coating method, flow coating method, etc., and may be appropriately selected depending on conditions such as the shape of the polycarbonate resin base material. The preferred thickness of the resulting undercoat film is 0.05 to 10
The thickness is preferably 0.5 to 5 microns.
If it is smaller than 0.05 micron, the adhesion will decrease, and if it is larger than 10 micron, the coating film may become cloudy or cracks may occur. The solid content of the undercoat composition is adjusted with the above-mentioned solvent depending on the coating method and conditions so as to obtain the desired thickness, and the solid content of the undercoat composition is approximately 1 to 20% by weight. Examples of polycarbonate resins to which the present invention can be applied include bisphenol type polycarbonates such as 4,4'-isopropylidene diphenol polycarbonate, as well as U.S. Patent No. 3305520
and other polycarbonates, diethylene glycol bisallyl carbonate, etc., described in "Polycarbonates", pp. 161-176 (published in 1962) by Christopher and Foxx. These are used as various molded products, such as eyeglass lenses, ski goggles, doors, automobile windows, and partitions. The broken polycarbonate resin molded article according to the present invention can be colored by dyeing its coating layer, if necessary. The dyeing method is, for example, in a dye bath containing general disperse dyes, dispersants, PH adjustment liquid, etc.
This is done by immersion treatment under conditions of 1 minute. In this way, a dyed article with excellent abrasion resistance can be obtained. The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited by these Examples. Note that parts and % in the examples indicate parts by weight and % by weight, respectively. The performance of the coating film was evaluated using the following method. That is, abrasion resistance: The resistance to scratching by rubbing with #0000 steel wool was examined and judged as follows. A: No damage occurs even if strongly rubbed. B: Slight scratches occur when rubbed strongly. C: Even weak friction causes scratches. Adhesion: In the so-called cross-cut tape test, 11 parallel lines are drawn vertically and horizontally at 1 mm intervals on the surface of the coating film, and 100 squares are cross-cut.
After adhering cellophane adhesive tape thereon, the tape was peeled off and the number of squares that did not peel off among 100 squares was indicated. Hot water resistance: The state of the coating film was examined after being immersed in boiling water for 1 hour. Heat resistance: The state of the coating film was examined after being stored in a hot air drying oven at 120°C for 100 hours. Chemical resistance: The state of the coating film was examined after being immersed in the following chemicals at room temperature for 100 hours. 8% sulfuric acid, 1% sodium hydroxide, 95% ethanol, acetone, ethyl acetate, carbon tetrachloride,
Toluene, n-heptane, 10% saline. Example 1 A top coat and an undercoat were prepared as follows. (1) Preparation of top coat; 80 parts of γ-glycidoxypropyltrimethoxysilane, 144 parts of methyltrimethoxysilane, colloidal silica (manufactured by Nissan Chemical Industries, Ltd., Snowtex-C, solid content 20%)
Mix 71 parts and 170 parts of 0.1N hydrochloric acid aqueous solution,
Hydrolysis was carried out by refluxing at 80-85°C for 2 hours. The obtained solution is γ-glycidoxypropyltrimethoxysilane hydrolyzate 12.2% _CH3SiO calculated as _1.5
It contained 15.3% methyltrimethoxysilane hydrolyzate calculated as SiO2 and 3.1% colloidal silica calculated as _SiO2 . The ternary cohydrolyzate solution obtained in this way
To 410 parts, 73 parts of ethyl cellosolve, 1.3 parts of ammonium perchlorate, and a small amount of flow control agent were added to make a top coat. (2) Preparation of undercoat paint; 400 parts of ethyl cellosolve,
While keeping a mixture of 190 parts of ethyl methacrylate and 10 parts of γ-methacryloxypropyltrimethoxysilane at 75°C under a nitrogen atmosphere, a solution of 1.0 part of benzoyl peroxide dissolved in 200 parts of ethyl cellosolve was added for 2 hours. 6 more
The temperature was maintained at the same time. Then ethyl cellosolve
1400 parts aluminum acetylacetonate 2
and 20 parts of 2,4-dihydroxybenzophenone were added to prepare an undercoat. This undercoat paint is applied to a pre-washed polycarbonate base material, and dried at 130℃ in a hot air drying oven.
It was heated and dried for 30 minutes. Next, the top coat prepared in (1) above was applied to the polycarbonate coated with the undercoat layer obtained in this manner, and was cured by heating and drying in a hot air drying oven at 130°C for 60 minutes. The coated polycarbonate molded article thus obtained is transparent, has an abrasion resistance of A, and an adhesion of 100/
100, the hot water resistance and heat resistance are good, and the abrasion resistance and adhesion after the hot water resistance test are A and A, respectively.
It was good at 100/100. Furthermore Sunshine Weather Ometer test
The appearance, hardness and adhesion after 1500 hours were extremely good. In addition, the chemical resistance was good for all chemicals, and no abnormality was observed in the appearance after the test. Comparative Example 1 The same procedure as in Example 1 was carried out except that the undercoat paint was prepared without using aluminum acetylacetonate. The coated polycarbonate molded article obtained in this manner was transparent, had an abrasion resistance of A, an adhesion of 100/100, and had good hot water resistance and heat resistance. was 0/100. Comparative Example 2 A mixture of 400 parts of ethyl cellosolve and 200 parts of ethyl methacrylate was kept at 75°C under a nitrogen atmosphere, and a solution of 1.0 part of benzoyl peroxide dissolved in 2000 parts of ethyl cellosolve was added once for 2 hours, and then for another 6 hours. It was kept at the same temperature. Thereafter, 1,400 parts of ethyl cellosolve and 20 parts of 2,4-dihydroxybenzophenone were added to prepare an undercoat. This primer paint is applied to a polycarbonate base material that has been cleaned in advance, and dried at 130℃ for 30 minutes in a hot air drying oven.
The mixture was dried by heating for a minute. Next, the top coat used in Example 1 was applied to the polycarbonate coated with the undercoat layer obtained in this manner, and was cured by heating and drying at 130° C. for 60 minutes. The coated polycarbonate molded article thus obtained is transparent, has an abrasion resistance of A, and an adhesion of 100/100.
However, the adhesion after the hot water resistance test was 0/
It was 100. Example 2 A top coat and an undercoat were prepared as follows. (1) Preparation of top coat; 60 parts of γ-glycidoxypropyltrimethoxysilane, 173 parts of methyltrimethoxysilane, colloidal silica (manufactured by Nissan Chemical Industries, Ltd., Snowtex-C, solid content 20%)
Mix 71 parts and 190 parts of 0.1N acetic acid aqueous solution,
Hydrolysis was carried out by refluxing at 80-85°C for 2 hours. The obtained solution is γ-glycidoxypropyltrimethoxysilane hydrolyzate 8.6%, calculated as CH ₃ SiO _1.5
It contained 17.3% methyltrimethoxysilane hydrolyzate calculated as SiO2 and 2.9% colloidal silica calculated as _SiO2 . The ternary cohydrolyzate solution obtained in this way
To 450 parts, 42 parts of ethyl cellosolve, 1.3 parts of ammonium perchlorate, and a small amount of flow control agent were added to make a top coat. (2) Preparation of undercoating paint: While keeping 300 parts of butyl cellosolve at 100°C under a nitrogen atmosphere, a mixture of 160 parts of methyl methacrylate, 40 parts of γ-methacryloxypropyltrimethoxysilane, and 2.0 parts of benzoyl peroxide was added for 3 hours. Once added,
The temperature was maintained for an additional 3 hours. After that, 1155 parts of butyl cellosolve, 363 parts of ethylene glycol diacetate, 0.4 part of partluenesulfonic acid, 2
-Hydroxy-4-methoxybenzophenone 80
A small amount of water and a flow control agent were added to make an undercoat. This primer paint is applied to a pre-washed polycarbonate base material and dried in a hot air drying oven for 130°C.
It was heated and dried at ℃ for 30 minutes. Next, the top coat prepared in (1) above was applied to the polycarbonate coated with the undercoat layer obtained in this manner, and was cured by heating and drying in a hot air drying oven at 130°C for 60 minutes. The coated polycarbonate molded article thus obtained is transparent, has an abrasion resistance of A, and an adhesion of
100/100, and the abrasion resistance and adhesion after the hot water resistance test were both A and 100/100, which were good. Furthermore, the appearance, hardness, and adhesion after 1500 hours of sunshine weather meter testing were extremely good. Example 3 A top coat and an undercoat were prepared as follows. (1) Preparation of top coat 77 parts of isopropyl alcohol, 60 parts of γ-glycidoxypropyltrimethoxysilane, 115 parts of methyltrimethoxysilane, colloidal silica (manufactured by Nissan Chemical Industries, Ltd., Snowtex-C, solid content 20%) ) 213 parts and 5 parts of 1N hydrochloric acid were added,
Hydrolysis was carried out by refluxing at 80-85°C for 2 hours. The obtained solution is Contains 9.1% γ-glycidoxypropyltrimethoxysilane hydrolyzate calculated as CH 3 SiO _1.5 , methyltrimethoxysilane hydrolyzate 12.1% calculated as CH ₃ SiO 1.5 and colloidal silica 9.1% calculated as SiO ₂ there was. The ternary cohydrolyzate solution obtained in this way
To 417 parts, 66 parts of ethyl cellosolve, 1.3 parts of ammonium perchlorate, and a small amount of flow control agent were added to make a top coat. (2) Preparation of undercoat paint; methyl isobutyl ketone
A mixture of 384 parts of methyl methacrylate, 20 parts of γ-methacryloxypropylmethyldimethoxysilane, and 1.0 part of azobisisobutyronitrile was added to a mixture of 384 parts of methyl methacrylate and 216 parts of methyl ethyl ketone at 90°C under a nitrogen atmosphere for 2 hours. In addition,
The temperature was maintained for an additional 5 hours. Then 624 parts of methyl butyl ketone, 576 parts of isopropyl alcohol
10 parts of a 10% aqueous solution of di-n-butylamine was added to prepare an undercoat. This primer paint is applied to a pre-cleaned polycarbonate substrate and dried in a hot air drying oven for 120 min.
It was heated and dried at ℃ for 30 minutes. Next, the top coat prepared in (1) above was applied to the polycarbonate coated with the undercoat layer obtained in this manner, and was cured by heating and drying in a hot air drying oven at 130°C for 60 minutes. The thus obtained coated polycarbonate molded article is transparent, has an abrasion resistance of A, and an adhesion of
The abrasion resistance and adhesion after the hot water resistance test were good as A and 100/100, respectively. Furthermore, the appearance, abrasion resistance, and adhesion after 1000 hours of sunshine weather meter testing were good, but the adhesion decreased to 80/100 after 1500 hours. Example 4 The undercoat paint of Example 3 was prepared in the same manner as in Example 3 except that vinyltrimethoxysilane was used in place of γ-methacryloxypropylmethyldimethoxysilane. The coated polycarbonate molded article obtained was transparent and had abrasion resistance and adhesion of A and 100/100, respectively, after a hot water resistance test. Furthermore, the appearance and abrasion resistance after 1,500 hours of sunshine weather meter testing were extremely good, but the adhesion was 80/100. Example 5 A top coat and an undercoat were prepared as follows. (1) Preparation of top coat; 80 parts of γ-glycidoxypropyltrimethoxysilane, 86 parts of methyltrimethoxysilane, colloidal silica (manufactured by Nissan Chemical Industries, Ltd., Snowtex-C, solid content 20%)
213 parts of isopropyl alcohol, 90 parts of isopropyl alcohol, and 35 parts of 0.1N aqueous hydrochloric acid were added, and the mixture was refluxed at 80 to 85°C for 2 hours to effect hydrolysis. The obtained solution is γ-glycidoxypropyltrimethoxysilane hydrolyzate 11.3%, calculated as
It contained 8.5% methyltrimethoxysilane hydrolyzate calculated as CH ₃ SiO _1.5 and 8.5% colloidal silica calculated as SiO ₂ . The ternary cohydrolyzate solution obtained in this way
To 417 parts, 66 parts of ethyl cellosolve, 1.0 part of ammonium perchlorate, and a small amount of flow control agent were added to form a top coat. (2) Preparation of undercoat paint; 400 parts of ethyl cellosolve,
140 parts of ethyl methacrylate, 40 parts of styrene,
A mixture of 20 parts of γ-methacryloxypropyltrimethoxysilane was kept at 75°C under a nitrogen atmosphere, and a solution of 1.0 part of benzoyl peroxide dissolved in 200 parts of ethyl cellosolve was added once for 2 hours, and the mixture was kept at the same temperature for an additional 8 hours. . Thereafter, 1400 parts of ethyl cellosolve, 4 parts of titanium tetraisopropoxy, and 30 parts of 2-(2'-hydroxy-5'-octylphenyl)benzotriazole were added to prepare an undercoat. This undercoat paint is applied to a pre-washed polycarbonate base material, and dried at 130℃ in a hot air drying oven.
It was dried by heating for 30 minutes. Next, the top coat prepared in (1) above was applied to the polycarbonate coated with the undercoat layer obtained in this manner, and was cured by heating and drying in a hot air drying oven at 120°C for 60 minutes. The coated polycarbonate molded article thus obtained is transparent and has excellent abrasion resistance after hot water resistance tests.
Adhesion was good at A and 100/100. Furthermore, the appearance, hardness, and adhesion after 1500 hours of Sunshine Weatherometer test were also extremely good.

Claims (1)

[Scope of Claims] 1 (a) A copolymer of an acrylic or/and vinyl monomer having an alkoxysilyl group and another monomer copolymerizable with these monomers, and (b) the above-mentioned Wear resistance: A composition containing 0.01 to 10% by weight of a curing catalyst based on the copolymer was coated and cured to form an undercoat layer, and a composition containing colloidal silica-containing organopolysiloxane was coated and cured to form an overcoat layer. A coated polycarbonate resin molded article with improved properties. 2. The composition containing the colloidal silica-containing organopolysiloxane contains at least one member selected from the group consisting of the following (A) and (B), (C) and (D), (A) General formula (1) [Formula ] (In the formula, R ¹ is an organic group having an epoxy group, R ²
is hydrogen, a hydrocarbon group having 1 to 6 carbon atoms, R ³ is a hydrocarbon group having 1 to 5 carbon atoms, an alkoxyalkyl group, or an acyl group having 1 to 4 carbon atoms, and a is 1 to 4 carbon atoms.
3, b is 0 to 2, and a+b≦3. ) One or more hydrolysates selected from silicon compounds having an epoxy group represented by (B) General formula (2) R ⁴ _c -Si-(OR ⁵ ) _4-c (2) (in the formula R ⁴ is a hydrocarbon group having 1 to 6 carbon atoms, a methacryloxy group, an amino group, a mercapto group, an organic group having fluorine or chlorine, and R ⁵ is a hydrocarbon group having 1 to 5 carbon atoms, an alkoxyalkyl group, or an alkoxyalkyl group having 1 to 5 carbon atoms. 1 to 4 acyl groups, and c is 0 to 3.) A composition comprising a hydrolyzate of an organosilicon compound represented by (C) colloidal silica and (D) a curing catalyst. The coated polycarbonate resin molded article described above. 3. The composition containing the colloidal silica-containing organopolysiloxane contains 100 parts by weight of the (A) hydrolyzate (calculated on solid content,
Calculate as [Formula]. ), 56 to 550 parts by weight of the above (B) hydrolyzate (calculated based on solid content)
Calculated as R ⁴ _c −Si−O _4-c . ), 4 to 334 parts by weight of the above (C) colloidal silica (calculated based on solid content and calculated as SiO ₂ ).However, the total of (B) and (C) is
The coated polycarbonate resin molded article according to claim 2, which is a composition comprising not more than 567 parts by weight of the curing catalyst (D). 4 The content of the hydrolyzate (B) is 105 to 430 parts by weight, and the content of the colloidal silica (C) is 16 to 430 parts by weight.
The coated polycarbonate resin molded article according to claim 3, wherein the amount is 200 parts by weight, and the total of (B) and (C) does not exceed 473 parts by weight. 5. A patent in which the curing catalyst (D) is selected from perchlorates, hydrochlorides, sulfates, nitrates, carboxylates, highly fluorinated aliphatic sulfonates, and highly fluorinated aliphatic sulfonyl compounds. Claim 2
The coated polycarbonate resin molded article described in 2. 6. The coated polycarbonate resin molded article according to claim 1, wherein the curing catalyst (b) is a curing catalyst selected from organic acids, organic acid metal salts, amines, metal acetylacetonates, and organic titanates.