JPH0724400A - Manufacture of film - Google Patents

Abstract

PURPOSE:To manufacture a film of uniform film thickness and without defects by agitating a coating composition a specified time (minutes) before immersing a material to be coated into the coating composition in the dip coating method. CONSTITUTION:When a plastic material is utilized as an optical element, a film is formed on the surface for the purpose of improving the defects of low surface hardness. Particularly a coating is applied by the dip coating method. In that case, a coating composition is agitated within 5 minutes before immersing a material to be coated into the coating composition in the dip coating method. Also inorganic fine particles are contained in the coating composition. A resin formed body is used as the material to be coated. Thus a film of uniform film thickness and without the surface defects such as foreign matters is manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a film having a uniform film thickness and no abnormal appearance.

[0002]

2. Description of the Related Art In general, plastic materials are lightweight, and are excellent in impact resistance, workability and mass productivity, so that the demand for optical elements such as optical filters, optical lenses and optical disks has been expanding in recent years. As these plastic materials for optical elements, transparent resins such as polymethylmethacrylate, polycarbonate, polyethersulfone, and N-substituted maleimide copolymer are known at present. However, plastic optical elements generally have the drawback of having a lower surface hardness than inorganic glass, and many attempts have been made to improve this. For example, SiO on the surface of plastic substrate
A method of coating an inorganic substance such as ₂ by vacuum deposition (Japanese Patent Laid-Open No. 58-204031) or a method of providing a polyorganosilane-based hard coat film or an acrylic hard coat film on the surface of a plastic substrate (USP 3,986). 99
7, USP 4,211,823, JP-A-57-1689.
No. 22, JP-A-5-38262, and JP-A-59.
-51908, JP-A-59-51954,
JP-A-59-78240 and JP-A-59-8936.
No. 8, JP-A-59-102964, JP-A-5
9-109528, JP-A-59-120663, JP-A-59-155437, JP-A-59-
Japanese Patent No. 174629, Japanese Patent Application Laid-Open No. 59-193969, Japanese Patent Application Laid-Open No. 59-204669).

Further, conventionally, as a coating means for coating,
Methods such as dip coating, bar coating, spin coating, spray coating, brush coating, roll coating and flow coating are used.

[0004]

The above-mentioned prior art S
Improvement of the surface hardness by vacuum deposition of inorganic substances such as iO ₂ has a high hardness, but on the other hand, there is a big problem that the adhesion to a substrate, heat resistance, light resistance and the like are deteriorated. Although the heat resistance is somewhat improved by the technique of providing a silane-based or acrylic-based hard coat film disclosed in Japanese Patent No. 38262, JP-A-59-51908, etc., its effect is insufficient. .

Further, in order to enhance its function, when a transparent conductive film, an antireflection film, a gas barrier film or the like is laminated alone or in combination on a plastic material for an optical element with a hard coat film, the transparent conductive film, the reflection film and the Since the difference in the linear expansion coefficient and the change in moisture absorption dimension between the preventive film, the gas barrier film and the resin molding is large, there is a problem that cracks easily occur in these films due to heating or the like and the durability is deteriorated.

In addition, for example, when it is used for a plastic substrate for liquid crystal, a method of increasing the amount of inorganic fine particles in the hard coat film has been attempted in order to enhance the durability of the transparent conductive film. For such applications in which high surface accuracy is required and the film thickness unevenness and foreign matter on the surface are a fatal defect, coating by the dip coating method has been conventionally performed. However, vibration of the liquid surface during pulling up, shaking of the object to be coated, change in pulling up rate, coating composition, especially appearance unevenness of the coating film due to uneven concentration of the coating tank surface, and uneven film thickness, In addition, there is a problem in that appearance defects are caused by foreign matter caused by aggregation of the inorganic fine particles. In particular, in the paint on the surface of the paint tank, coating unevenness due to a change in composition due to solvent evaporation is observed, which is a big problem in the dip coating method.

The present invention is intended to solve the above problems and provides a method for producing a coating film having a uniform film thickness and no surface defects.

[0008]

To achieve the above object, the present invention has the following constitution.

[In the dip coating method, within 5 minutes before dipping the article to be coated in the coating composition,
A method for producing a coating, which comprises stirring the coating composition. First, the coating composition will be described.

The coating composition is not particularly limited as long as it can be coated on the object to be coated, but a composition which is cured by heating or irradiation with ultraviolet rays is preferable.

For example, acrylic resins, silicone resins, polyurethane resins, melamine resins, polyolefin resins, celluloses, polyvinyl alcohol resins, polyvinylidene chloride resins, polyvinyl chloride resins, urea resins, nylon resins, polycarbonate resins. Resins such as resins and epoxy resins may be used alone, or those containing two or more kinds may be mentioned. Particularly for applications where surface hardness is important, a curable resin is preferable, and for example, an acrylic resin, a silicone resin, an epoxy resin, a polyurethane resin, a melamine resin is preferably used alone or in combination. To be done.

In consideration of transparency, heat resistance and workability, epoxy resins are preferable among these resins.
Specific examples of the epoxy resin include bisphenol A type epoxy resin, tetramethylbisphenol A type epoxy resin, tetrabromobisphenol A type epoxy resin,
Bisphenol F type epoxy resin, tetramethylbisphenol F type epoxy resin, bisphenol S type epoxy resin, tetramethylbisphenol S type epoxy resin, bisphenol AF type epoxy resin, bisphenol Z type epoxy resin, bisphenol fluorene type epoxy resin, biphenol type epoxy resin , Tetramethylbiphenol type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin,
Examples thereof include aliphatic epoxy resins. These may be used alone or in a mixture of two or more.

Among the above epoxy resins, transparency, coatability on an object to be coated, adhesiveness to an object to be coated, and a functional film such as a transparent conductive film, an antireflection film or a gas barrier film laminated on the film. From the viewpoint of durability, bisphenol A type epoxy resin is preferable.

Furthermore, improvement of surface hardness, adjustment of refractive index,
Inorganic fine particles may be contained for the purpose of improving mechanical strength, thermal characteristics, and conductivity. Specific examples of the inorganic fine particles include silica, antimony oxide, titania, alumina, zirconia, and tungsten oxide. These may be one kind or a mixture of two or more kinds.

For example, in the coating composition applied to a plastic substrate for a liquid crystal display, it is particularly preferable to use inorganic fine particles, and silica or antimony oxide is preferable, from the viewpoint of improving thermal characteristics and durability of a transparent conductive film. is there. From the viewpoint of improving workability and imparting transparency, it is preferable that these inorganic fine particles are uniformly mixed in the coating composition as a colloidally dispersed sol. Specific examples of the colloidally dispersed sol include silica sol,
Examples thereof include titania sol, zirconia sol, ceria sol, antimony oxide sol, magnesium fluoride sol, indium tin oxide (ITO) sol, and tin oxide sol. The average particle size of the inorganic fine particles is not particularly limited, but is generally 1 to 200 mμ, preferably 5 to 60 mμ, and more preferably 8 to 50 mμ. If the average particle size exceeds 200 mμ, the resulting coating has poor transparency and tends to become turbid. Also, less than 5 mμ or 100 m
When it exceeds μ, the durability of the functional film such as the transparent conductive film, the antireflection film and the gas barrier film laminated on the article to be coated tends to be insufficient. Further, there is no problem even if various fine particle surface treatments are performed to improve the dispersibility of the inorganic fine particles, or various surfactants, amines, etc. are added.

Further, in consideration of various characteristics such as surface hardness, heat resistance, chemical resistance and transparency, addition of a silicone resin as an organic polymer is also preferable. More preferably, an organic silicon compound represented by the following general formula (1) or a hydrolyzate thereof can be added.

R ¹ _a R ² _b SiX _4-ab (1) (wherein R ¹ is an organic group having 1 to 10 carbon atoms, and R ²
Is a hydrocarbon group having 1 to 6 carbon atoms or a halogenated hydrocarbon group, X is a hydrolyzable group, and a and b are 0 or 1.
Is. ) Examples of the organosilicon compound represented by the general formula (1) include methyl silicate, ethyl silicate, and n.
-Propyl silicate, iso-propyl silicate,
Tetraalkoxysilanes such as n-butyl silicate, sec-butyl silicate, and t-butyl silicate, and hydrolysates thereof, and further methyltrimethoxysilane, methyltriethoxysilane, methyltriacetoxysilane, methyltripropoxysilane, Methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriacetoxysilane, γ-chloropropyltri Methoxysilane, γ-chloropropyltriethoxysilane, γ-chloropropyltriacetoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-aminopropyl Trimethoxysilane, γ-aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, β-cyanoethyltriethoxy Silane, methyltriphenoxysilane, chloromethyltrimethoxysilane, chloromethyltriethoxysilane, glycidoxymethyltrimethoxysilane, glycidoxymethyltriethoxysilane, α-glycidoxyethyltrimethoxysilane, α-glycidoxy Ethyltriethoxysilane, β-glycidoxyethyltrimethoxysilane, β-glycidoxyethyltriethoxysilane,
α-glycidoxypropyltrimethoxysilane, α-glycidoxypropyltriethoxysilane, β-glycidoxypropyltrimethoxysilane, β-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltripropoxysilane, γ-glycidoxypropyltributoxysilane, γ-glycidoxypropyltriphenoxysilane,
α-glycidoxybutyltrimethoxysilane, α-glycidoxybutyltriethoxysilane, β-glycidoxybutyltrimethoxysilane, β-glycidoxybutyltriethoxysilane, γ-glycidoxybutyltrimethoxysilane, γ-glycidoxybutyltriethoxysilane, δ-glycidoxybutyltrimethoxysilane, δ-
Glycidoxybutyltriethoxysilane, (3,4-epoxycyclohexyl) methyltrimethoxysilane,
(3,4-epoxycyclohexyl) methyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane, β- (3,4)
-Epoxycyclohexyl) ethyltripropoxysilane, β- (3,4-epoxycyclohexyl) ethyltributoxysilane, β- (3,4-epoxycyclohexyl) ethyltriphenoxysilane, γ- (3,4-epoxycyclohexyl) propyl Trimethoxysilane,
trialkoxysilanes such as γ- (3,4-epoxycyclohexyl) propyltriethoxysilane, δ- (3,4-epoxycyclohexyl) butyltrimethoxysilane, δ- (3,4-epoxycyclohexyl) butyltriemethoxysilane, Triacyloxysilane, or triphenoxysilane or its hydrolyzate, and dimethyldimethoxysilane, phenylmethyldimethoxysilane, dimethyldiethoxysilane, phenylmethyldiethoxysilane, γ-chloropropylmethyldimethoxysilane, γ-chloropropylmethyldiene Ethoxysilane, dimethyldiacetoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-mercaptopropylmethyldimethoxy Silane, γ-mercaptopropylmethyldiethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, methylvinyldimethoxysilane, methylvinyldiethoxysilane, glycidoxymethylmethyldimethoxysilane, glycidoxy Methylmethyldiethoxysilane, α-glycidoxyethylmethyldimethoxysilane, α-glycidoxyethylmethyldiethoxysilane,
β-glycidoxyethylmethyldimethoxysilane, β-
Glycidoxyethylmethyldiethoxysilane, α-glycidoxypropylmethyldimethoxysilane, α-glycidoxypropylmethyldiethoxysilane, β-glycidoxypropylmethyldimethoxysilane, β-glycidoxypropylmethyldiethoxysilane , Γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropylmethyldipropoxysilane, γ-glycidoxypropylmethyldibutoxysilane, γ-glycidoxypropyl Methylmethoxyethoxysilane, γ-glycidoxypropylmethyldiphenoxysilane, γ-glycidoxypropylmethyldiacetoxysilane, γ-glycidoxypropylethyldimethoxysilane, γ-glycidoxypropylethyldiethoxysila , Γ-glycidoxypropylvinyldimethoxysilane, γ-glycidoxypropylvinyldiethoxysilane, γ-glycidoxypropylphenyldimethoxysilane, γ-glycidoxypropylphenyldiethoxysilane and other dialkoxysilanes, diphenoxy Mention may be made of silanes or diacyloxysilanes or their hydrolysates. These organosilicon compounds may be used alone or in combination of two or more. In particular, for the purpose of imparting dyeability, it is preferable to use an organic silicon compound containing an epoxy group or a glycidoxy group, which gives a high added value.

The organosilicon compound is preferably used after being hydrolyzed in order to lower the curing temperature and accelerate the curing. Hydrolysis is produced by adding pure water or an acidic aqueous solution such as hydrochloric acid, acetic acid or sulfuric acid, and stirring. Furthermore, the degree of hydrolysis can be easily controlled by adjusting the amount of pure water or acidic aqueous solution added. At the time of hydrolysis, it is preferable to add pure water or an acidic aqueous solution in an amount of equimolar or more and 3 times or less the molar amount of the hydrolyzable group contained in the compound represented by the general formula (1) from the viewpoint of promoting the curing.

During the hydrolysis, since alcohol or the like is produced, it can be hydrolyzed without a solvent. However, after the organosilicon compound and the solvent are mixed for the purpose of making the hydrolysis more uniform, the hydrolysis is performed. It is also possible to disassemble. It is also possible to remove an appropriate amount of alcohol after hydrolysis under heating and / or reduced pressure for use depending on the purpose, and to add an appropriate solvent after that.

Further, polyvinyl alcohol can be used for applications requiring gas barrier properties and antifogging properties. The degree of saponification and the degree of polymerization of polyvinyl alcohol depend on the gas barrier property,
From the viewpoint of antifogging property and workability, it should be appropriately determined experimentally, but a saponification degree of 50 to 95 mol% and an average degree of polymerization of 300 to 1200 are preferably used.

Further, the coating composition used in the present invention is usually diluted with a volatile solvent for the purpose of improving workability and adjusting the film thickness. The solvent used is not particularly limited, but it is required that the surface properties of the material to be coated are not impaired in use,
Further, it should be determined in consideration of the stability of the composition, the wettability to the object to be coated, the volatility, and the like.
Further, the solvent may be used not only as one kind but also as a mixture of two or more kinds. Examples of these solvents include water, alcohols, esters, ethers, ketones, halogenated hydrocarbons, aromatic hydrocarbons such as toluene and xylene, and aprotic polar solvents. From the viewpoint of dispersibility of inorganic fine particles, water, methyl alcohol,
Ethyl alcohol, isopropyl alcohol, n-propyl alcohol, dimethylformamide, ethylene glycol, diethylene glycol, triethylene glycol, benzyl alcohol, phenethyl alcohol, 1,
4-dioxane, phenyl cellosolve, N-methyl-2
-Pyrrolidone, dimethyl sulfoxide, 1,3-dimethyl-2-imidazolidinone and the like solvents are preferably used.

Further, in the coating composition used in the present invention, various curing agents can be used in combination for the purpose of accelerating curing and curing at low temperature. Specific examples of these curing agents include various organic acids and their acid anhydrides,
Nitrogen-containing organic compounds, various metal complex compounds, metal alkoxides, various salts of alkali metal organic carboxylates and carbonates, and radical polymerization initiators such as peroxides and azobisisobutyronitrile And so on. These curing agents can be used as a mixture of two or more kinds. Among these curing agents, the following aluminum chelate compounds are particularly useful for the purpose of the present invention from the viewpoints of the stability of the coating composition and the presence or absence of coloring of the coating film after coating.

The aluminum chelate compound as used herein is, for example, an aluminum chelate compound represented by the general formula AlX _n Y _3-n . However, X in the formula is OL (L represents a lower alkyl group), Y
Is a ligand derived from a compound represented by the general formula M ¹ COCH ₂ COM ² (M ¹ and M ² are both lower alkyl groups) and the general formula M ³ COCH ₂ COOM ⁴ (M ³ and M ⁴ are both Is a lower alkyl group), and n is 0, 1 or 2.

As the aluminum chelate compound represented by the general formula AlX _n Y _3-n , various compounds can be mentioned, but they are particularly preferable from the viewpoints of solubility in the composition, stability, effect as a curing catalyst and the like. Are aluminum acetylacetonate, aluminum bisethylacetoacetate monoacetylacetonate, aluminum-di-n-butoxide-monoethylacetoacetate, aluminum-di-iso-propoxide-monomethylacetoacetate and the like. These may be used alone or in admixture of two or more.

The coating composition used in the present invention may be dyed with various dyes, especially disperse dyes. In the case of dyed products, various transition metals are used for the purpose of improving the light fastness thereof. It does not matter if the compound or its reaction product is added. Specific examples of these metal compounds include, for example, acetylacetonate metal salts, bisdithiol-α-diketone metal salts, bisphenylthiol metal salts, bisphenyldithiol metal salts, thiocatechol metal salts, dithiocarbamic acid metal salts, Examples thereof include salicylaldehyde oxime metal salt, thiobisphenolate metal salt, and phosphonous metal salt. Among them, acetylacetonate chelate compounds are preferably used because they have good stability in coating materials. The amount of these transition metal compounds added should be determined experimentally depending on the intended use of the material to be coated, the type of diluent solvent and the type of other components, but from the viewpoint of solubility, whitening of the coating film, etc. It is preferably used in the range of 0.001 to 10% by weight. If it is less than 0.001% by weight, the effect of addition cannot be obtained, and if it is added in an amount of 10% by weight or more, the coating film becomes cloudy and is not preferable. Further, these transition metal compounds cause no problem even if the bonding state of the metal changes due to some chemical change during the formation of the transparent film, but in order to obtain a greater effect, they are contained in the film as chelate compounds. It is preferable.

To the coating composition used in the present invention, various surfactants are added for the purpose of improving the flow at the time of application, improving the smoothness of the coating and lowering the friction coefficient of the coating surface. In particular, a block or graft copolymer of dimethylpolysiloxane and alkylene oxide, and a fluorine-based surfactant are particularly effective. The usage of these is 0.0
1 to 5% by weight is preferable, and if it exceeds 5% by weight, the transparency tends to be insufficient, and if it is less than 0.01% by weight, the effect of addition such as coating unevenness tends to be insufficient.

Further, an inorganic oxide other than the inorganic fine particles may be added to the coating composition used in the formation of the transparent film of the present invention within a range not significantly degrading the film performance and transparency. By using these additives in combination, adhesion with the substrate, chemical resistance, surface hardness, durability,
It is possible to improve various properties such as dyeability. Examples of the inorganic material that can be added include metal alkoxides represented by the following general formula (2), chelate compounds and / or hydrolysates thereof.

M (OR) _m (2) (wherein R is an alkyl group, an acyl group or an alkoxyalkyl group, and m is the same as the number of charges of the metal M. M is silicon, titanium, zircon, Antimony, tantalum, germanium, aluminum, etc.) It is also possible to add an ultraviolet absorber for the purpose of further improving weather resistance, or an antioxidant as a method for improving heat deterioration resistance.

The coating composition used in the present invention can be cured by heat treatment, ultraviolet irradiation, plasma treatment, etc. In the case of heat curing, the heating temperature depends on the composition of the coating composition and the heat resistance of the material to be coated. Although it is appropriately selected in consideration of the above, it is preferably 50 to 250 ° C.
Further, the film thickness of the cured film is 0.1 to 10 μm.
Is preferred. If it is less than 0.1 μm, the surface hardness tends to be insufficient, and if it exceeds 10 μm, the transparency tends to be insufficient.

The present invention relates to a method for producing a coating film by a dip coating method. The dip coating method is a method of immersing an object to be coated in a coating composition, pulling up the object to be coated, and coating the applied coating composition. This is a method of curing by heating or the like.

In the present invention, it is necessary to stir the coating composition within 5 minutes before immersing the article to be coated in the coating composition. The stirring is usually performed by a known method, and examples thereof include stirring with stirring blades, stirring by circulating the coating composition with a pump, and stirring by ultrasonic waves. Further, it is also effective to scrape off the paint on the surface of the paint tank with a spatula to remove the paint in which an abnormality such as an abnormal concentration of the paint tank surface or the inclusion of foreign matter has occurred. The method included in. In particular, stirring by pump circulation is preferable from the viewpoint of effective stirring. As a circulation method, a conventionally known method can be used, but a plunger pump, a rotary pump or the like can be used. Further, at this time, it is desirable to carry out circulation filtration in which filtration is performed simultaneously. By this filtration, aggregates are removed, and the quality of the coating material is dramatically improved. The filter material and the mesh of the filter material in the filtration should be appropriately experimentally determined, but a filter material made of polytetraethylene, polypropylene, nitrocellulose or the like having a size of 10 μm or less is preferable.

In the present invention, when coating is carried out continuously without stirring, concentration unevenness occurs on the liquid surface and inside of the coating composition with the lapse of time, resulting in uneven coating film thickness and abnormal appearance. Tends to cause. In the case of using a coating composition containing inorganic fine particles, an aggregate of inorganic fine particles adheres to the inner wall of the coating tank or the upper wall of the coating tank capable of overflowing, and the coating composition is formed by dipping the material to be coated. There is a case where the liquid surface rises and the aggregates of the inorganic fine particles are taken into the coating composition to cause foreign matter. In particular, the content of inorganic fine particles in the coating composition is 10
In the case of the weight% or more, stirring by circulation filtration is preferable.
More preferably, the content of the inorganic fine particles in the coating composition is 15% by weight or more.

The coating composition may be agitated at least once within 5 minutes before the material to be coated is dipped in the coating composition. However, the thickness of the coating film tends to be uneven, and surface defects due to foreign matter or the like tend to occur. However, it does not matter that the stirring is started 5 minutes before the immersion and the stirring is continued continuously for 5 minutes before the immersion. The stirring time is not particularly limited as long as the material to be coated can be stirred within at least 5 minutes before being immersed in the coating composition, but is 10 seconds or longer, preferably 20 seconds or longer, and more preferably 30 seconds or longer.

From the viewpoint of completely preventing surface defects due to foreign matters, it is more preferable to stir the material to be coated within at least 3 minutes before it is immersed in the coating composition, and more preferably within 30 seconds. . Also,
Agitation during immersion of the object to be coated is possible, but agitation during pulling up is not preferable because it causes coating unevenness of the coating composition, and during pulling up, the liquid level of the coating composition It is preferable not to cause the turbulence as much as possible.

The dipping speed of the material to be coated is not particularly limited, but is preferably 50 cm / sec to 10 cm / sec. When the object to be coated is pulled up, it is preferable to pull it up at a constant speed when aiming to make the coating film thickness uniform.
The pulling rate should be appropriately determined by experiments, but is preferably 50 cm / sec to 3 cm / sec.

The object to be coated used in the present invention is not particularly limited in its shape and material as long as it can be dip coated. For example, examples of the shape include a plate-shaped object, a gut-shaped object, a tube-shaped object, a lens-shaped object, and a complicated-shaped object such as a toy, a musical instrument, and sports equipment. Examples of the material include glass, metal, wood, paper, plastic, and composite materials of various materials.

The present invention is effectively used particularly when a coating composition is applied to a plastic material to improve scratch resistance or to impart gas barrier properties, conductivity and the like to improve functionality. It

In applying the coating composition of the present invention, it is an effective means to subject the article to be coated to various pretreatments for the purpose of improving cleaning, adhesion, water resistance and the like, and it is particularly preferably used. Examples of the method that can be used include activation gas treatment, chemical treatment, and ultraviolet treatment.

The activated gas treatment is a treatment with ions, electrons or excited gas produced under normal pressure or reduced pressure. As a method of generating these activated gases, for example, corona discharge, direct current under reduced pressure,
This is due to low voltage, high frequency or high voltage discharge by microwaves. In particular, the treatment with low temperature plasma obtained by high frequency discharge under reduced pressure is preferably used from the viewpoint of reproducibility and productivity.

The gas used here is not particularly limited, but specific examples are oxygen, nitrogen, hydrogen, carbon dioxide, sulfur dioxide, helium, neon, argon, freon, water vapor, ammonia, carbon monoxide. , Chlorine, nitric oxide, and nitrogen dioxide. These can be used not only as one type but also as a mixture of two or more types. Among the above, preferred gases include those containing oxygen,
It may be one that exists in the natural world such as air. More preferably, pure oxygen gas is effective for improving adhesion. Furthermore, for the same purpose, the temperature of the substrate to be treated can be raised in the treatment.

On the other hand, specific examples of the chemical treatment include alkali treatment with caustic soda and the like, acid treatment with hydrochloric acid, sulfuric acid, potassium permanganate, potassium dichromate and the like, organic solvent treatment and the like. The above pretreatments can be carried out continuously or stepwise in combination.

The coating method of the present invention can be applied to various materials such as resin moldings, metal products, glass, paper products and woodworking products. In particular, surface protection of resin moldings and transparency on resin moldings are possible. When a functional film such as a conductive film, an antireflection film, or a gas barrier film is used alone or in combination to provide a function, a film is formed as a buffer material between the resin molded body and the functional film, or a transparent conductive film, It is useful for forming a gas barrier film. Further, it can also be used for forming a film for protecting functional films such as a transparent conductive film, an antireflection film and a gas barrier film.

For example, for use as a plastic substrate for a liquid crystal display, which requires heat resistance, transparency, solvent resistance, gas barrier properties, and low surface resistance, resin molding can be performed on the resin molding by the method of the present invention. A transparent coating film having a buffering effect between the body and the inorganic film is formed, and a gas barrier film containing SiO ₂ as a main component and a transparent conductive film containing ITO as a main component are laminated and used as a resin plate with a conductive film, A gas barrier film composed mainly of polyvinyl alcohol and SiO ₂ ,
Further, a transparent coating film having a buffering effect between the resin molded body and the inorganic film is formed by the manufacturing method of the present invention, and a transparent conductive film containing ITO as a main component is further laminated to be used as a resin plate with a conductive film.

The resin molded product used for the above purpose is not particularly limited as long as it is a resin molded product having a glass transition temperature of 130 ° C. or higher, but a resin having a glass transition temperature of 150 ° C. or higher can be used. In this case, the heat resistance is further improved and it is more preferably used. Here, the glass transition temperature refers to the temperature at which a polymer changes from an amorphous glass state to a rubber state, but in the transition region, elastic modulus, expansion coefficient,
Various properties such as heat content, refractive index and dielectric constant change. The glass transition temperature can be measured from the change in these characteristics, and specifically, it can be evaluated by a known method such as differential scanning calorimetry (DSC) (for example, JIS K712.
1). When measuring the glass transition temperature by differential scanning calorimetry, the glass transition temperature can be determined by evaluating the resin molded product itself or heat-treated one, but if the transparent coating is sufficiently thin, resin molding It is also possible to regard the glass transition temperature of an article having a transparent coating on the body as the glass transition temperature of a transparent resin.

The mechanical properties of the resin molded product are preferably 200 kg / mm ² , and more preferably 330 kg when the flexural modulus at room temperature is used as an index.
/ Mm ² or more. Furthermore, the transparency of the resin molding is
When the total light transmittance when uncolored is used as an index, it is 60
% Or more, more preferably 80% or more.
The resin molded body can be made into a composite system with an inorganic substance or the like as long as the transparency is not impaired, and there is no problem even if the resin molded body contains an inorganic bond such as a siloxane bond or a phosphazene bond.

Examples of the components of the resin molded product include polyolefin resins represented by polymethacrylic acid resins such as polymethacrylic acid and polycarboxyphenylmethacrylamide, polystyrene resins such as poly (biphenyl) styrene, and poly (poly (biphenyl) styrene). 2,6-dimethyl-1,4-
Polyether resin represented by phenylene oxide), polycarbonate resin represented by poly (oxycarbonyloxy-1,4-phenylene isopropylidene-1,4-phenylene), poly (oxy-2,2,2)
Polyester resin represented by 4,4-tetramethyl-1,3-cyclobutyleneoxyterephthaloyl), poly (oxy-1,4-phenylenesulfonyl-1,4-)
Phenylene), poly (oxy-1,4-phenylene isopropylidene-1,4-phenyleneoxy-1,4-phenylenesulfonyl-1,4-phenylene), and other polysulfone-based resins, poly (iminoisophthaloyl) Polyamide resin represented by imino-4,4′-biphenylene), polysulfide resin represented by poly (thio-1,4-phenylenesulfonyl-1,4-phenylene), unsaturated polyester resin, epoxy resin Examples thereof include resins, melamine-based resins, phenol-based resins, diallylphthalate-based resins, polyimide-based resins, polyphosphazene-based resins, and the like, and it is also possible to introduce a crosslinked structure in these polymer groups. In particular, maleimide resins are preferable from the viewpoint of transparency and moldability, and maleimide copolymers obtained by polymerizing a composition containing a polyfunctional monomer having two or more unsaturated groups are more preferably used. To be

The above-mentioned copolymer is represented by the following general formula (3)
20 to 98% by weight of a monomer represented by the formula (1) and 2 to 80% by weight of a polyfunctional monomer having two or more unsaturated groups, and a monomer represented by the general formula (3). The total weight ratio of the monomer and the polyfunctional monomer having two or more unsaturated groups is
A copolymer obtained by polymerizing 30% by weight or more of the composition is preferably used.

[0048]

[Chemical 1] (In the formula, R ³ represents a substituent selected from hydrogen and a hydrocarbon group having 1 to 20 carbon atoms. R ⁴ and R ⁵ represent a substituent selected from hydrogen, a methyl group and an ethyl group.) General formula R contained in the maleimide derivative compound represented by (3)
⁴ and R ⁵ may be the same or different.

When R ³ is a hydrocarbon group, specific examples include a methyl group, an ethyl group, a propyl group, an octyl group,
Linear alkyl group such as octadecyl group, isopropyl group, sec-butyl group, tert-butyl group, branched alkyl group such as isopentyl group, cyclohexyl group, alicyclic hydrocarbon group such as methylcyclohexyl group, phenyl group Examples include various groups such as an aryl group such as a methylphenyl group, an aralkyl group such as a benzyl group, and a phenethyl group.

Further, R ⁴ , R ⁵ and R ³ are substituted with various substituents such as halogeno group such as fluorine, chlorine and bromine, cyano group, carboxyl group, sulfonic acid group, nitro group, hydroxy group and alkoxy group. It may have been done.

Specific examples of the compound represented by the general formula (3) include N-methylmaleimide, N-butylmaleimide, N-phenylmaleimide, N-o-methylphenylmaleimide, Nm-methylphenylmaleimide and N-methylmaleimide. −
p-Methylphenylmaleimide, N-o-hydroxyphenylmaleimide, Nm-hydroxyphenylmaleimide, Np-hydroxyphenylmaleimide, N-methoxyphenylmaleimide, Nm-methoxyphenylmaleimide, Np-methoxyphenyl Maleimide, N
-O-chlorophenyl maleimide, Nm-chlorophenyl maleimide, Np-chlorophenyl maleimide,
Examples include N-o-carboxyphenylmaleimide, Np-carboxyphenylmaleimide, Np-nitrophenylmaleimide, N-ethylmaleimide, N-cyclohexylmaleimide, N-isopropylmaleimide and the like.

These monomers may be used alone or as a mixture of two or more. Among these maleimide compounds, alkylmaleimide and cycloalkylmaleimide are particularly preferable, and N-iso-propylmaleimide and N-cyclohexylmaleimide are particularly preferable, from the viewpoints of yellowing after the heat resistance test and weather resistance. Furthermore, from the viewpoint of ease of preparation of a monomer solution at the time of cast polymerization and the ability to satisfy the above characteristics, N-iso is used.
Most preferred is the combined use of N-alkylmaleimide and N-alicyclic alkylmaleimide such as -propylmaleimide and N-cyclohexylmaleimide. The ratio of N-alkylmaleimide and N-alicyclic alkylmaleimide when used in combination is
It should be appropriately determined experimentally depending on the type and amount of the polyfunctional monomer having two or more unsaturated groups.
Usually, in order to bring out the effect of the combined use, it is preferable to use 10 to 500 parts by weight of N-alicyclic maleimide with respect to 100 parts by weight of N-alkylmaleimide.

Next, the polyfunctional monomer having two or more unsaturated groups will be described. That is, the polyfunctional monomer having two or more unsaturated groups is a monomer having two or more unsaturated functional groups copolymerizable with the maleimide, and as the copolymerizable functional group, a vinyl group, Methyl vinyl group,
Examples thereof include an acrylic group and a methacrylic group. Further, a monomer having two or more different copolymerizable functional groups in one molecule is also included in the polyfunctional monomer in the present invention.

Specific preferred examples of the polyfunctional monomer having two or more unsaturated groups as described above include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate and triethylene glycol di (meth) acrylate. , Glycerol (di / tri) (meta)
Acrylate, trimethylolpropane (di / tri)
Di-, tri-, tetra- (meth) acrylates of polyhydric alcohols such as (meth) acrylate, pentaerythritol (di / tri / tetra) (meth) acrylate,
aromatic polyfunctional monomers such as p-divinylbenzene and o-divinylbenzene, esters such as (meth) acrylic acid vinyl ester and (meth) acrylic acid allyl ester, dienes such as butadiene, hexadiene and pentadiene, and dichlorophosphazene. Examples of the raw material include a monomer having a phosphazene skeleton having a polymerized polyfunctional group introduced therein, and a polyfunctional monomer having a heteroatom cyclic skeleton such as triallyl isocyanurate. The maleimide-based copolymer composition preferably contains 20 to 98% by weight of the monomer represented by the general formula (3).
If it is less than 20% by weight, sufficient heat resistance, mechanical strength,
In some cases, characteristics such as optical isotropy cannot be satisfied. On the other hand, when it exceeds 98% by weight, the degree of cross-linking may be lowered, and solvent resistance, low water absorption, etc. may be insufficient. Further, it is preferably 30 to 80% by weight, and more preferably 40 to 60% by weight.

On the other hand, the polyfunctional monomer having two or more unsaturated groups is preferably contained in the crosslinked polymer composition in a proportion of 2 to 80% by weight, and when it is less than 2% by weight. In some cases, crosslinking does not proceed sufficiently, and heat resistance, solvent resistance, etc. tend to decrease. On the other hand, if it exceeds 80% by weight, impact resistance and the like may be deteriorated, resulting in a problem that the characteristics of the plastic may be significantly deteriorated.

Furthermore, in the above maleimide type copolymer composition, the mechanical strength is improved, the optical isotropy is improved, the refractive index is increased, the water absorption is decreased, the dyeability is improved, the heat resistance is improved, and the impact resistance is improved. For the purpose of improvement, various copolymerizable monomers are preferably used in combination. Examples of such monomers that can be used in combination include aromatic vinyl-based monomers, olefin-based vinyl monomers, (meth) acrylic acid and its ester-based monomers, and polyvalent carboxylic acid anhydrides. Specific examples of the aromatic vinyl-based monomer include styrene, α-methylstyrene, p-methylstyrene, p-tert-butylstyrene, chlorostyrene and bromostyrene. Usually, styrene, α-methylstyrene, p-methylstyrene, and the like are used from the viewpoint of performance and industrial availability. Examples of other vinyl-based monomers include vinyl cyanide-based monomers such as acrylonitrile and methacrylonitrile, methyl methacrylate, methyl acrylate, cyclohexyl methacrylate, t-butyl methacrylate, benzyl methacrylate, and acrylic. Preferable specific examples include (meth) acrylic acid (ester) -based monomers such as acid and methacrylic acid, and maleic anhydride. Copolymerization of vinylcycloalkane such as vinylcyclohexane is effective for applications requiring low water absorption.

The total content of the monomer represented by the general formula (3) and the polyfunctional monomer having two or more unsaturated groups in the above polyolefin-based copolymer composition is It is preferably 30% by weight or more, and more preferably 40% by weight or more. That is, if it is less than 30% by weight, the polymer may have insufficient transparency, heat resistance, chemical resistance, impact resistance and the like.

It is also useful to add various ultraviolet absorbers, antioxidants, and antistatic agents to the resin molded product for the purpose of improving light resistance, resistance to oxidative deterioration, and antistatic property. In particular, it is possible to improve these performances without lowering the chemical resistance and heat resistance, so it is
Alternatively, it is preferable to copolymerize a monomer having an antioxidant property. Preferred examples of such a monomer include a benzophenone-based UV absorber having an unsaturated double bond, a phenylbenzoate-based UV absorber having an unsaturated double bond, and a (meth) acrylic monomer having a hindered amino group as a substituent. Is mentioned. These copolymerization monomers are preferably used in the range of 0.5 to 20% by weight. If it is less than 0.5% by weight, no addition effect is observed, and if it exceeds 20% by weight, heat resistance,
Mechanical strength tends to decrease.

The method for polymerizing the resin molded body is not particularly limited, and it can be polymerized by a generally known method. When the resin molded product is a vinyl-based copolymer, it can be polymerized by keeping the above-mentioned monomer mixture under a predetermined temperature condition in the presence or absence of a radical initiator. Various methods such as bulk polymerization, solution polymerization, suspension polymerization and cast polymerization can be used. The degree of polymerization of the resin molded product of the present invention is not particularly limited, but a higher polymerization rate is preferable, and 90% or more is preferable in consideration of solution coating such as a transparent film and post-processing such as vacuum deposition. The transparent resin of the present invention can be polymerized in a temperature range of 30 to 250 ° C., but the polymerization rate can be increased by setting the polymerization temperature to 130 ° C. or higher, more preferably 150 ° C. or higher.

The molding method of the resin molded body is not particularly limited, but an effective molding method is a cast polymerization method.

The mechanical properties of the resin molded product according to the present invention are represented by the flexural modulus at 170 ° C. as an index:
For applications where heat resistance is important, 20 kg / mm ^{2 to} 300 kg / mm
It is preferably ² . If it is less than 20 kg / mm ² ,
Insufficient rigidity causes problems in mechanical properties.
If it exceeds kg / mm ² , the crosslinked resin may crack during handling, which may cause a problem such as poor yield. In order to achieve the above flexural modulus, in the present invention, it is necessary to heat-treat the crosslinked resin and the transparent coating obtained above. As the heat treatment method, a known method such as a method using a heater or a method applying light such as infrared rays can be used.

The heat treatment atmosphere may be gas, solution, or under reduced pressure. Preferably, yellowing due to oxidation of the object to be treated, from the viewpoint of workability, particularly under reduced pressure or nitrogen, carbon dioxide, helium, neon,
A gas atmosphere such as argon is applied. They are,
Not only one kind but also a mixture of two or more kinds can be used.
The heat treatment temperature should be determined according to the substrate and the transparent film to be applied, but is usually 100 to 300.
C, more preferably 120-250 C is applied. At temperatures lower than this, no clear effect is observed, and at temperatures higher than this, thermal decomposition, cracking, etc. occur, and problems such as yellowing are likely to occur. Further, the heat treatment time is appropriately selected in consideration of the shape of the crosslinked resin to be applied, the transparent film and the heat treatment temperature, but is preferably 1 second to 24 hours, more preferably 1 minute to 12 hours. If it is shorter than this, no obvious effect is observed, and if it is longer than this, problems such as yellowing and workability tend to occur. Further, as a method for fixing the object to be treated during the heat treatment, a known method can be used, which should be experimentally determined depending on the shape of the object, the thickness and the heat treatment temperature, and the heat treatment time. When the object to be treated is a sheet, heat treatment on a flat plate-like support is preferable, and particularly when surface smoothness of the object to be treated is required, the surface smoothness of the flat plate-like support becomes important, As the support, glass materials such as polishing glass and ground glass, metal materials such as aluminum and stainless steel, and polymer materials such as Teflon and polyimide are preferably used.

The object to be coated obtained as described above can be coated with the coating composition according to the present invention to form a transparent conductive film such as ITO, which can be used as a transparent conductive film material. Transparent conductive film materials for capacitors, resistors and other electrical parts circuit materials, electrophotographic and electrostatic recording copying materials, liquid crystal displays, electrochromic displays, electroluminescent displays, touch panel signal input transparent In addition to photoelectric conversion elements such as electrodes, solar cells, and optical amplifiers, it can be used for various applications such as antistatic, electromagnetic wave shielding, surface heating elements, and sensors. When a resin molded product having a transparent conductive film such as ITO formed thereon is used, its conductivity can be maintained even at high temperatures, so that it can be used as a heat-resistant transparent conductive film material.

Further, when used for a liquid crystal display substrate application, for example, the transparent coating formed on the resin molding according to the present invention has a uniform film thickness and has no abnormal appearance. A metal oxide film and a metal nitride film having excellent durability can be laminated on both surfaces individually or in combination. The method for forming the metal oxide film and the metal nitride film is not particularly limited, and includes bipolar sputtering, tripolar or quadrupolar sputtering, high speed low temperature (magnetron) sputtering, ion beam sputtering, facing target sputtering,
A generally known sputtering method such as high frequency discharge sputtering, reactive sputtering, bias sputtering, asymmetrical AC sputtering, getter sputtering and the like can be used. For example,
The metal oxide film and / or the metal nitride film formed by the high frequency discharge sputtering method uses a dielectric or a metal oxide or a metal nitride which is an insulator as a sputtering gate, and is used in an inert gas atmosphere and / or an active gas atmosphere. The film is formed in the atmosphere. Examples of the metal oxide film and / or the metal nitride film include Al, Si, Zr, and T.
Examples thereof include metal oxides and / or nitrides of one kind or a mixture of two or more kinds selected from i, Y, Yb, Mg, Ta, Ce, Hf and the like, and cost, transparency, gas barrier property, metal From the viewpoint of the durability of the transparent conductive film provided on the oxide film and / or the metal nitride film, Al, S
A metal oxide and / or nitride of one or a mixture of two or more selected from i and Ti is suitable. He, Ne, A is used as the sputtering gas.
An inert gas such as r, Kr, Xe, or Rn is preferably used, but Ar is particularly preferably used from the viewpoints of cost, availability, and sputtering rate. O ₂ , N ₂ , CO, CO ₂ or the like is used as the active gas, and O ₂ is preferably used for the purpose of compensating for O ₂ deficiency during sputtering when forming the metal oxide film. O
_{The 2} concentration (partial pressure with respect to the inert gas) is appropriately selected depending on the type of transparent film, the substrate temperature, the target material, the sputtering rate, and the input power.
0% is typical. In the present invention, 5% or less is preferable from the viewpoint of reducing plasma damage of the transparent coating,
It is more preferably 1% or less. Metal oxide film and /
Also, the film thickness of the metal nitride film is not particularly limited, but from the viewpoint of film formation time, imparting gas barrier properties, and durability of the transparent conductive film, it is preferably 50 to 2000 angstroms, and more preferably 100 to 1200 angstroms.

As the transparent conductive film, metal oxides such as ITO, tin oxide and cadmium oxide, metals such as gold, silver, copper, palladium, nickel, aluminum and chromium, and conductive thin films such as conductive polymers are used. To be Among them, ITO is preferably used in consideration of various characteristics such as transparency and low resistance. As a method for forming an ITO film or the like, known methods such as a vacuum vapor deposition method, an ion plating method, a sputtering method, a coating method, and a spray method can be used. In addition, as a sputtering method,
A known method such as a direct current method, a high frequency method, or a magnetron method is used [see the sputtering phenomenon (Kanehara Takeshi, published by The University of Tokyo Press, 1984)]. The substrate temperature at the time of film formation is appropriately selected depending on the type of resin molded body, coating film, etc., in consideration of transparency, low resistance, adhesiveness, heat resistance, and chemical resistance. Further, the composition ratio of ITO is preferably determined by the surface resistance value, the specific resistance, the transparency, etc. required for the transparent conductive film, but from the viewpoint of low resistance and transparency,
The SnO ₂ content is preferably 25% by weight or less, and in order to further lower the resistance value, it is preferable to use a high-density ITO target in which the ITO target is close to the true density of ITO. . The film thickness of the transparent conductive film is not particularly limited, but is 150 from the viewpoint of conductivity and film formation time.
It is preferable to be appropriately selected from the range of up to 5000 angstroms. The manufacturing method of the coating film of the present invention is TN (Tw
ist Nematic) type, STN (Super)
Twisted Nematic) type, Ferroelectric Liquid Crystal (FLC)
Simple matrix type such as Cristal type, MI
M (Metal-Insulator-Metal)
Type, TFT (Thin-Film Transistor)
It can be applied to the production of active matrix type plastic substrates for liquid crystal displays, such as r) type, but is preferably used for the production of simple matrix type plastic substrates for liquid crystal displays because the manufacturing process is relatively simple.

When a resin plate coated with a film produced by the present invention, that is, a resin film coated with a gas barrier film and / or a hard coat film is used as a substrate for a liquid crystal display, a metal nitride may be optionally formed on the coated product. It is possible to form a resin plate with a conductive film by laminating a metal oxide and / or a metal oxide and further forming a transparent conductive film, and the liquid crystal is sandwiched between the transparent conductive film surfaces of the resin plate with a transparent conductive film. That is, in the liquid crystal display using the conventional glass substrate, the glass substrate is replaced by the resin plate with the transparent conductive film. If necessary, a structure in which a liquid crystal layer is sandwiched by a substrate in which a passivation film is provided on a transparent conductive film and an alignment film is provided thereon is used. A deflection plate is provided outside the substrate holding the liquid crystal layer. A liquid crystal display further includes a retardation plate, a light reflection plate, or the like, if necessary.

As a method of manufacturing a liquid crystal display using a resin plate with a transparent conductive film, a known method can be applied. For example, in the case of a simple matrix type liquid crystal display [Liquid crystal device handbook (edited by Japan Society for the Promotion of Science, 142nd Committee, published by Nikkan Kogyo Shimbun, 1989)]
p. 531], after cleaning the substrate, transparent conductive film formation, transparent conductive film fine processing (resist coating, development, etching,
(Resist cleaning and removal), alignment film formation, rubbing treatment, cleaning, sealing agent printing, substrate bonding, heating / pressurization, vacuum degassing, liquid crystal injection, injection port sealing, liquid crystal cell cutting, deflection plate / light reflection plate, etc. A liquid crystal display device is obtained by sequentially performing steps such as sticking. In these liquid crystal display manufacturing steps, the manufacturing conditions should be set in consideration of various characteristics such as heat resistance, mechanical characteristics, and mechanical characteristics of the liquid crystal display substrate using the resin molded body.

When used in the production of optical articles for which optical properties are important as described above, the transparency of the resin molded product with a coating is 60 when the total light transmittance when uncolored is used as an index. % Or more is preferable, and 80% is more preferable. In addition, when it is applied to applications where optical isotropy is required, for example, substrates for liquid crystal displays, optical disk substrates, etc., the birefringence of the resin molded product with a coating is preferably 30 nm or less, more preferably 15 nm or less. .

In the method for producing a coating film of the present invention, since the film thickness is uniform and surface defects due to foreign matters are few, spectacle lenses, sunglasses lenses, camera lenses, video camera lenses, goggle lenses, contact lenses, etc. For optical lenses, in addition to optical disc substrates, liquid crystal display substrates, liquid crystal display light guide plates, electrochromic display substrates, electroluminescent display substrate materials, and other display substrate materials, automobiles, aircraft fronts, etc. Suitable for coating window substrates such as rear and roof,
In particular, it is suitable for manufacturing substrate materials for various displays such as substrates for liquid crystal displays that require surface accuracy.

[0070]

EXAMPLES The present invention will be described more specifically below based on examples.

The total light transmittance in the examples was measured using an SM computer manufactured by Suga Test Instruments Co., Ltd. For the solvent resistance, the surface was rubbed with gauze impregnated with acetone, and the change in gloss at that time was visually evaluated. Further, the glass transition temperature was measured using Mettler DSC30. The value is 2n according to JIS standard K-7121.
The Tmg of the drun was read.

The film thickness of the coating was measured with a surface roughness measuring instrument SE-3300 manufactured by Kosaka Laboratory Ltd., and the appearance was visually observed.

The surface resistance of the resin plate with the conductive film was measured by Loresta MCP-TESTER manufactured by Mitsubishi Petrochemical Co., Ltd.
-It measured at room temperature using FP. For gas barrier property evaluation, oxygen permeability was measured by a differential pressure steady method using a differential pressure type gas permeability measuring system GTR-30XD manufactured by Yanagimoto Seisakusho. Furthermore, as the durability evaluation of the conductive film,
The heat resistance was determined by heating for 2 hours in an oven set to 180 ° C., cooling to room temperature, and visually observing the appearance of the resin plate with a conductive film. For chemical resistance, a 3% aqueous sodium hydroxide solution is heated to 40 ° C. and the resin plate with the conductive film is immersed for 5 minutes,
After that, wash with running water for 5 minutes and replace with purified water.
It was drained with gauze and the appearance was visually observed.

Example 1 (1) Method for Manufacturing Resin Molded Body An example of a method for manufacturing a resin molded body will be described below.

N-isopropylmaleimide 20.5 g N-cyclohexylmaleimide 6.0 g Styrene 18.5 g Divinylbenzene 5.0 g Azobisisobutyronitrile 0.05 g were mixed and dissolved, and cast-molded by cast polymerization.
Cast polymerization was performed as follows.

Size 150 mm × 150 mm, thickness 5 mm 2
The outer peripheral portions of the two glass plates were bonded with a gasket made of soft vinyl chloride and assembled so that the distance between the two glass plates was 0.5 mm. The above-mentioned monomer mixture was poured into the assembled glass plate and polymerized at 70 ° C. for 8 hours, 100 ° C. for 1 hour, and further at 150 ° C. for 1 hour to obtain a transparent resin molding.

The glass transition temperature of this resin molding is 185.
C., and the total light transmittance was 90%. The solvent resistance was also good.

(2) Preparation of coating composition (I) A reactor equipped with a rotor was charged with 10 g of phenyltrimethoxysilane, the liquid temperature was kept at 20 ° C., and stirring was performed with a magnetic stirrer to 0.01 N. 2.7 g of the hydrochloric acid aqueous solution of was gradually added dropwise. Stop cooling after the dropping,
A hydrolyzate of phenyltrimethoxysilane was obtained.

43 g of diacetone alcohol, 30 g of dimethylformamide, 73 g of benzyl alcohol, 0.7 g of silicon-based surfactant, 0.7 g of bisphenol A type epoxy resin (produced by Yuka Shell Epoxy Co., Ltd .; Product name Epicote 82
7) 43 g was added and mixed, and colloidal silica sol (manufactured by Catalysts & Chemicals Industry Co., Ltd., trade name OSCAL-123
5, average particle diameter 45 mμ) 337 g, and aluminum acetylacetonate 2.8 g were added and sufficiently stirred,
The coating composition (I) was used.

(3) Formation of coating film The coating composition (I) obtained in (2) above was transferred to an overflow type coating tank equipped with a circulation filtration device using a plunger pump, and 5 minutes before immersion of the material to be coated. To 30 seconds before, the coating composition (I) was agitated by circulation filtration (filter material: 0.5 μm PTFE membrane filter) at a flow rate of 2 L / min, and then the resin molding obtained in (1) above was dipped at a dipping speed. 30 cm
/ Min. Then, the coating was completed at a dipping speed of 20 cm / min. Further, continuously, the coating composition (I) was stirred before dipping in the same manner as above to coat 30 resin moldings. The coating composition was cured by pre-curing at 90 ° C. for 10 minutes, and
It heated at 0 degreeC for 1 hour, and formed the transparent film on the resin molding. When the film thickness of the resin molded product with a transparent film was measured, the film thickness unevenness was 1.4 μm ± 0.2 μm, and the film thickness range between the simultaneously applied plates was 0.2 μm or less. And had an excellent film thickness distribution. Further, no surface defects such as foreign matter were observed.

[0081] (4) on the resulting transparent film coated resin molded body by the conductive film coated resin plate production method (3) above, by the SiO ₂ high frequency discharge sputtering, data - using the SiO ₂ to target material, Ultimate vacuum 5 × 1
Set to 0 ^-5 Toor, use Ar as sputter introduction gas, sputter deposition vacuum degree 2 × 10 ^-3 Toor, input power 1.5 kw, substrate temperature 120 ° C., sputtering rate under 50 angstrom / min sputtering conditions. ,
A 600 angstrom film is formed, and a transparent conductive thin film containing indium-tin mixed oxide (ITO) as a main component is further formed thereon by a DC magnetron sputtering method.
ITO (SnO ₂ 10 wt%) was used as the target material, the ultimate vacuum was set to 5 × 10 ⁻⁵ Toor, the sputtering film introduction vacuum was Ar and O ₂ , and the sputtering film formation vacuum was 2 × 10 ⁻³ Toor. A film having a thickness of 2000 angstrom was formed under the conditions of an input power of 1.5 kw, a substrate temperature of 120 ° C. and a sputtering rate of 100 angstrom / min. The surface resistance of the surface on which the ITO film was formed at room temperature was ²⁰ Ω / cm ² . When heat resistance and chemical resistance were evaluated using this resin plate with a conductive film, there was no change in appearance, and when the surface resistance was measured, it was 20 Ω / cm ² , which was the same as the initial value. , And confirmed to have chemical resistance. Also, the oxygen transmission rate is
It showed 0.4 cc / m ² · day · atm and had a good gas barrier property. Example 2 (1) Preparation of coating composition (II) 95.3 g of γ-glycidoxypropyltrimethoxysilane was charged into a reactor equipped with a rotor, the liquid temperature was kept at 10 ° C, and a magnetic stirrer was used. 0.0 with stirring
21.8 g of 1N hydrochloric acid aqueous solution is gradually added dropwise. After completion of dropping, cooling was stopped to obtain a hydrolyzate of γ-glycidoxypropyltrimethoxysilane.

5 g of the hydrolyzate of phenyltrimethoxysilane and an aqueous solution of polyvinyl alcohol (average degree of polymerization: 600, degree of saponification: 91.0 to 94.0 mol%) of 50 wt% 9
0 g, water 260 g, 1,4-dioxane 50 g, methyl alcohol 100 g, fluorosurfactant 0.5 g, and further colloidal silica sol (manufactured by Catalysts & Chemicals Industry Co., Ltd., trade name OSCAL-1132, average particle diameter 11 mμ) 16
6 g of aluminum acetylacetonate and 5 g of aluminum acetylacetonate were added to a beaker and sufficiently dissolved with stirring to obtain a coating composition (II).

(2) Formation of film Coating was performed in the same manner as in Example 1 except that the coating composition (I) described in (3) of Example 1 was changed to the coating composition (II) of the above (1). A transparent film was provided on each of the resin moldings.

When the film thickness of these transparent resin-coated resin moldings was measured, the film thickness unevenness was as small as 0.9 μm ± 0.1 μm, and the film thickness range between the simultaneously applied plates was 0. It had an excellent film thickness distribution of 0.2 μm or less. Further, no surface defects such as foreign matter were observed.

The oxygen transmission rate of this coated substrate was 0.08 cc / m ² · day · atm, and had a good gas barrier property.

Example 3 The same procedure as in Example 1 (3) was repeated except that the resin molded article of (3) of Example 1 was changed to the resin molded article with a transparent film obtained in (2) of Example 2 to obtain a transparent film. 30 sheets of resin molded product with attached were obtained. No surface defects such as foreign matter were found on these coatings.

Further, when a SiO ₂ film and an ITO film were formed on the above resin molded product with a transparent film in the same manner as in Example 1, the surface resistance of the surface on which the ITO film was formed at room temperature was
It was 22 Ω / cm ² . When heat resistance and chemical resistance were evaluated using this resin plate with a conductive film, there was no change in appearance, and when the surface resistance was measured, it was 22 Ω / cm ² , which was the same as the initial value. , And confirmed to have chemical resistance. The oxygen transmission rate is 0.07 cc
/ M ² · day · atm, and had a good gas barrier property.

Comparative Example 1 In (3) of Example 1, when a transparent coating was provided on the resin molded body without stirring the coating material before dipping the object to be coated, the first five sheets showed no surface defects due to foreign matters or the like. Although it was not observed, foreign matter was generated on the surface of the film after the 6th sheet, and the film thickness of the film of these transparent resin-coated resin moldings was measured. As a result, the film thickness unevenness was 1.4 μm ± 0.5 μm. The film thickness range was 0.5 μm, and the film thickness distribution was insufficient.

Comparative Example 2 In Example 3, except that stirring by circulation filtration was carried out from 10 minutes before to 6 minutes before immersion of the material to be coated.
Similarly, a resin molding with a transparent film was obtained. As a result, no surface defects due to foreign matter were found on the first 7 sheets, but on the eighth and subsequent sheets, foreign matter adhered to the coating surface,
When the film thickness of these resin molded articles with a transparent film was measured, the film thickness unevenness was as large as 2.5 μm ± 0.5 μm, and the film thickness range within the plate was 0.7 μm and the film thickness distribution was also unsatisfactory. Was enough.

[0090]

According to the present invention, on the article to be coated,
It is possible to obtain a coating film having excellent film thickness uniformity and free from surface defects such as foreign matter.

Claims (3)

[Claims] 1. A method for producing a coating film, wherein in the dip coating method, the coating composition is stirred within 5 minutes before the material to be coated is immersed in the coating composition. 2. A method for producing a coating film according to claim 1, wherein the coating composition contains inorganic fine particles. 3. The method for producing a coating film according to claim 1, wherein the article to be coated is a resin molding.