JPH033712B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an erasable coating material composition with excellent wear resistance. Molded products made of thermoplastic resins such as polymethyl methacrylate resin, polycarbonate resin, ABS resin, nylon resin, and PET resin generally have ridges.
Although this is considered an important characteristic depending on the application, there are also many applications where the absence of such a bar is preferred, and on the other hand, in recent years, it has become possible to improve the reflection without sacrificing optical properties such as total light transmittance. The use of pine boards and non-glare boards, which scatter light and eliminate rays, is also increasing. Conventionally, the methods for achieving such fade-proofing of molded products include adding fine particles of silica, titanium oxide, aluminum oxide, etc. to paint and painting them, or mixing them with resin and applying these particles to the surface during molding by some method. They were manufactured by raising the material to eliminate the burrs, by molding it in a mold that already had a finely textured surface, or by using cast polymerization in a cell that had a finely textured surface. However, silica
When paints that simply contain titanium oxide, aluminum oxide, etc. are stored, their dispersion stability deteriorates over time, resulting in hard sedimentation that is difficult to redisperse.
Or the degree of erasure may change. Furthermore, in the method of obtaining a matted molded product using a mold or cell cast transfer, it is necessary to pay close attention to the maintenance and management of the entire mold and cells. However, in any case, even if a matte molded product can be obtained temporarily with this method, the surface has poor abrasion resistance and scratch resistance, so it is easily scratched and the matte surface is damaged. It ends up. In order to improve these shortcomings, the present inventors continued intensive studies and found that in the presence of specific polyfunctional acrylates and organic solvents, specific sulfonic acid monomers, sulfonate monomers, or carboxylic acid monomers, and radical polymerization. When polymerization was carried out in a polymerization system to which vinyl monomer and inorganic fine particles were added, a coating composition was obtained in which a composite in which the inorganic fine particles and the vinyl monomer polymer were firmly united was uniformly dispersed. I got something. When this was applied as an erasable coating composition to a plastic molded article and cured, it was discovered that an erasable molded article with excellent wear resistance and scratch resistance could be obtained, and the present invention was completed. That is, the gist of the present invention is that (a) 30% by weight or more of a compound having at least 3 (meth)acryloyloxy groups in one molecule and 1 to 2 α,β-ethylenic groups in one molecule; A monomer mixture (A) consisting of 70% by weight or less of a compound having a saturated bond, (b) the following general formula for 100 parts by weight of the monomer mixture (A): (In the formula, R ₁ is H, an alkyl group having 1 to 20 carbon atoms, a phenyl group and its derivatives, or a halogen atom, X is -CONH-,

[Formula] −COO(CH ₂ ) _n −, or. (CH ₂ ) _o −, and R ₂ and R ₃ are each H
or an alkyl group having 1 to 15 carbon atoms, R ₄ is an alkylene group having 1 to 15 carbon atoms, m is an integer of 1 to 20,
n is an integer from 0 to 20, Y represents H, NH ₄ or an alkali metal atom) The following general formula (In the formula, R ₁ is H, an alkyl group having 1 to 15 carbon atoms, COOY, a halogen atom or a phenyl group and its derivatives, R ₂ is H, an alkyl group having 1 to 15 carbon atoms, COOZ, a halogen atom or a phenyl group) and its derivatives, R ₃ is H, carbon number 1
~15 alkyl groups, halogen atoms or phenyl groups and their derivatives, X, Y, Z each represent H, NH ₄ or an alkali metal atom) or the following general formula (In the formula, R ₄ and R ₅ are each H, carbon number 1 to
At least one monomer selected from the group consisting of sulfonic acid monomers, sulfonate monomers, or carboxylic acid monomers represented by
0.01 to 20 parts by weight of a mixture (B) of inorganic fine particles and at least one radically polymerizable vinyl monomer, and (c) 100 parts by weight of an organic solvent (C) per 100 parts by weight of the monomer mixture (A). At least one photosensitizer (E) is added to the composition (D) obtained by polymerizing the polymerization system {(A) + (B) + (C)} of ~2000 parts by weight. Monomer mixture (A)
The present invention provides an erasable coating material composition with excellent abrasion resistance, which is blended in an amount of 0.01 to 6.0 parts by weight per 100 parts by weight. In the present invention, the compound having at least three (meth)acryloyloxy groups in one molecule is essential for improving the abrasion resistance and abrasion resistance of the coating composition. In order to obtain scratch resistance, these trifunctional or higher functional compounds should account for 30% by weight or more of the monomer mixture (A), and the trifunctional or higher functional compounds should contain 1 to 2 α,
Monomer mixture with β-ethylenically unsaturated bond
The average molecular weight per polymerizable unsaturated group in (A) is
Must be 300 or less. 3 in 1 molecule
If the content of compounds having more than one (meth)acryloyloxy group is less than 30% by weight, or even if these compounds are 30% by weight or more, the monomer mixture is
The average molecular weight per polymerizable unsaturated group in (A) is 300
If it exceeds this, sufficient abrasion resistance and scratch resistance may not be obtained. Examples of compounds having three or more (meth)acryloyloxy groups in one molecule include trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, pentaglycerol tri(meth)acrylate, and pentaerythritol tri(meth)acrylate. ) acrylate, pentaerythritol tetra(meth)acrylate, glycerin tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa( Poly(meth)acrylate, tripentaerythritol tetra(meth)acrylate, tripentaerythritol penta(meth)acrylate, tripentaerythritol hexa(meth)acrylate, tripentaerythritol hepeta(meth)acrylate, and other poly(meth)acrylates. Acrylate; malonic acid/trimethylolethane/(meth)acrylic acid/trimethylolpropane/(meth)acrylic acid, malonic acid/glycerin/(meth)acrylic acid, malonic acid/pentaerythritol/(meth)
Acrylic acid, succinic acid/trimethylolethane/
(meth)acrylic acid, succinic acid/trimethylolpropane/(meth)acrylic acid, succinic acid/glycerin/(meth)acrylic acid, succinic acid/pentaerythritol/(meth)acrylic acid, adipic acid/trimethylolethane/( Meth)acrylic acid, adipic acid/trimethylolpropane/(meth)acrylic acid, adipic acid/pentaerythritol/(meth)acrylic acid, adipic acid/glycerin/(meth)acrylic acid, glutaric acid/trimethylolethane/(meth) ) Acrylic acid, glutaric acid/trimethylolpropane/(meth)acrylic acid, glutaric acid/glycerin/(meth)acrylic acid, glutaric acid/pentaerythritol/(meth)acrylic acid, sebacic acid/trimethylolethane/(meth) Acrylic acid, sebacic acid/trimethylolpropane/(meth)acrylic acid, sebacic acid/glycerin/(meth)acrylic acid, sebacic acid/pentaerythritol/(meth)acrylic acid, fumaric acid/trimethylolethane/(meth)
Acrylic acid, fumaric acid / trimethylolpropane / (meth)acrylic acid, fumaric acid / glycerin / (meth)acrylic acid, fumaric acid / pentaerythritol / (meth)acrylic acid, itaconic acid /
Trimethylolethane/(meth)acrylic acid, itaconic acid/trimethylolpropane/(meth)acrylic acid, itaconic acid/pentaerythritol/
Saturated or unsaturated polyester poly(meth)acrylate made from a combination of compounds such as (meth)acrylic acid, maleic anhydride/trimethylolethane/(meth)acrylic acid, maleic anhydride/glycerin/(meth)acrylic acid; trimethylol Propane toluylene diisocyanate, or the following general formula (In the formula, R represents an isocyanate residue of hexamethylene diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, 4,4'-methylenebis(cyclohexyl isocyanate), isophorone diisocyanate, trimethylhexamethylene diisocyanate), etc. Acrylic monomers with the indicated polyisocyanates and active hydrogen, such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxy-3-methoxypropyl (meth)acrylate, N-methylol (meth)acrylate
Urethane acrylate obtained by reacting three or more acrylamide, N-hydroxy(meth)acrylamide, etc. per molecule of isocyanate by a conventional method; tri(meth)acrylate of tris-(2-hydroxyethyl-)isocyanuric acid, etc. I can do it. As a compound having 1 to 2 α,β-ethylenically unsaturated bonds in one molecule, any ordinary monomer with radical polymerization activity can be used, but the polymerizable unsaturated group A compound having a (meth)acryloyloxy group is preferable because it has excellent polymerization activity by ultraviolet rays. Specific examples of these compounds include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, and compounds having two (meth)acryloyloxy groups in one molecule. Tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 1,4-butanediol di(meth)
Acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate; tolylene diisocyanate, xylene diisocyanate, naphthalene diisocyanate, diisocyanate such as hexamethylene diisocyanate, tetramethylene diisocyanate, lysine diisocyanate, 4,4'-diphenylmethane diisocyanate, and an acrylic monomer containing active hydrogen, such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxy-
3-Methoxypropyl (meth)acrylate, N
- Urethane acrylate obtained by reacting two methylol (meth)acrylamide, N-hydroxy (meth)acrylamide, etc. per molecule of isocyanate in a conventional manner; or the following general formula: (In the formula, R ₁ is hydrogen or methyl group, X ₁ , X ₂ ...
Xn is the same or different alkylene group having 6 or less carbon atoms, or a structure in which one hydrogen atom of the alkylene group is replaced with a hydroxyl group, n is an integer from 0 to 5), for example, 2,2-bis -(4acryloxyphenyl-)propane, 2,2-bis-(4methacryloxyphenyl-)propane, 2,2-bis-(4acryloxyethoxyphenyl-)propane,
2,2-bis-(4methacryloxydiethoxyphenyl-)propane, 2,2-bis-(4acryloxydiethoxyphenyl-)propane, 2,2-bis-(4
methacryloxydiethoxyphenyl)propane,
2,2-bis-(4acryloxypropoxyphenyl-)propane, 2,2-bis-(4methacryloxypropoxyphenyl-)propane, 2,2-bis-[
4acryloxy(2hydroxypropoxy)phenyl-]propane, 2,2-bis-[4methacryloxy(2hydroxypropoxy)phenyl-]propane, 2,2-bis-[4acryloxy(2hydroxypropoxyethoxy)phenyl-]propane ，
Examples include 2,2-bis-[4methacryloxy(2hydroxypropoxyethoxy)phenyl]propane. Compounds having one (meth)acryloyl group in one molecule include methyl (meth)acrylate, propyl (meth)acrylate, butyl acrylate, isobutyl acrylate, t-butyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, Tridecyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, glycidyl acrylate, tetrahydrofurfuryl acrylate, benzyl acrylate, 1,4-butylene glycol acrylate, ethoxyethylene acrylate, ethyl carbitol acrylate, 2-hydroxy -3
-Chloropropyl acrylate, acrylamide, N-hydroxymethyl (meth)acrylamide, N-hydroxyethyl (meth)acrylamide, N-hydroxypropyl (meth)acrylamide, N-hydroxybutyl (meth)acrylamide, hydroxymethyl diacetone acrylamide, N -Hydroxyethyl-N-(methyl)acrylamide, etc. can be mentioned. Among these compounds, the following general formula is used as a compound having three or more (meth)acryloyloxy groups in one molecule. (In the formula, X ₁₁ , X ₁₂ , X ₁₃ , X ₂₂ , X ₂₃ ...Xn ₂ ,
At least three of Xn ₃ and X ₁₄ are CH ₂ = CH−
COO- group and the rest are hydroxyl group, amino group, alkylene group, substituted alkylene group, etc., n
is an integer from 2 to 5), such as dipentaerythritol triacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, etc., are curable by ultraviolet rays in air. It is particularly preferred, and when considering workability, cost, etc., it is better to use one or more of these compounds in 20% or more of the compounds having at least three (meth)acryloyloxy groups in one molecule. . Also used in combination with these for similar purposes 1
Examples of compounds having 1 to 2 (meth)acryloyloxy groups in the molecule include compounds represented by the general formula [], such as 2,2-bis-(4-acryloxyethoxyphenyl)propane, 2, 2-bis-(4-acryloxydiethoxyphenyl-)propane, 2,2-bis-(4-acryloxypropoxyphenyl-)propane, 2,2-bis-[4-acryloxy-(2-hydroxy) propoxy) phenyl]
Propane, 2,2-bis-[4-acryloxy-(2
-Hydroxypropoxyethoxy)phenyl-]propane, etc. are preferred as the difunctional monomer;
Examples of functional monomers include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, glycidyl acrylate, tetrahydrofurfuryl acrylate, ethoxyethyl acrylate, ethyl carbitol acrylate, butoxyethyl acrylate, 1,4-butylene glycol monoacrylate, etc. Hydroxyl groups and/or cyclic ether bonds and/or
Acrylates having a chain ether bond are particularly preferred since they have excellent polymerization activity when exposed to ultraviolet light in normal atmosphere. The sulfonic acid monomer, sulfonate monomer or carboxylic acid monomer represented by the general formula [], [] or [] is a monomer mixture (A), inorganic fine particles, radically polymerizable vinyl monomer and organic solvent. It is essential for forming a composite of vinyl monomer polymer and inorganic fine particles that exhibits uniform and stable dispersibility in the polymerization system blended with (C).
Of course, even if sulfonic acid monomer, sulfonate monomer, and vinyl monomer are not blended, a molded product may be obtained by blending only inorganic fine particles, but the viscosity of this composition is 100 cps/20 ℃
In particular, the dispersion stability of the inorganic fine particles in the coating composition is poor, and if left for a long time, they may solidify in the form of a cake at the bottom and may not be redispersed. Further, since the dispersibility of the inorganic fine particles in the coating composition is poor, it is impossible to obtain a uniform faded pattern at all. However, as mentioned above, in a mixture of a specific polyfunctional acrylate and an organic solvent, inorganic fine particles and at least one monomer that can be radically polymerized are mixed with a sulfonic acid monomer, a sulfonate monomer, or a carboxylic acid monomer. The composite that is firmly unified by the process does not require a dispersion step in the coating composition, and has very good dispersion stability in the coating composition. When using this method, it is possible to easily obtain a plastic molded product that has excellent wear resistance, scratch resistance, uniformity of the erasing pattern, and extremely excellent erasing effect. Although the detailed mechanisms of the dispersibility and dispersion stability of the composite in the coating composition and the ability to develop a uniform faded pattern have not been fully elucidated, the composite with an organic polymer in the outer layer , that an organic polymer is interposed between an inorganic substance, an organic polyfunctional (meth)acrylate, and an organic solvent;
It is thought that a part of the polyfunctional acrylate monomer is copolymerized into a polymer consisting of vinyl monomer due to the reaction in the presence of the polyfunctional acrylate monomer, and the former is strongly integrated into the outer layer of the inorganic fine particles. The combination of the good compatibility of the organic matter and the further compatibility improvement effect of the latter results in good dispersibility and dispersion stability of the coating composition, as well as a uniform and excellent erasing effect. considered to be a thing. Sulfonic acid monomers, sulfonate monomers, or sulfonic acid monomers represented by the general formula [ ], [ ], or [ ] used to produce composites of inorganic fine particles and organic polymers include combinations of inorganic and organic substances. The presence of a sulfonic acid group or carboxylic acid group that has a specific polymerization activity and a double bond that creates a strong bond between the resulting polymer and the inorganic substance is essential, and compounds with structural formulas containing these functional groups are essential. All can be applied, such as 2-acrylamido-2-methylpropanesulfonic acid (hereinafter referred to as
AMPS), 2-sodium methacrylate sulfonate (hereinafter abbreviated as SEM-Na), 3-
Sodium methacrylicpropanesulfonate (hereinafter abbreviated as SPS), sodium 2-propenesulfonate (hereinafter abbreviated as NaAS), 2-methyl-2
- Sodium propenesulfonate (hereinafter referred to as
NaMS), acrylic acid, methacrylic acid, crotonic acid, tiglic acid, cinnamic acid, maleic anhydride, citraconic anhydride, etc., but especially AMPS containing amide bonds and AMPS containing ester bonds.
SEM-Na and SPS or acrylic acid, methacrylic acid and crotonic acid have high polymerization activity and are preferred. The inorganic fine particles used in the present invention are 1 mμ
It is preferable to have a particle size of ~100μ, and it is preferable to adjust the polymerization so that the composite of inorganic fine particles and organic matter has a particle size of 1mμ to 100μ.
5m in terms of erasability, dispersibility and dispersion stability.
More preferably, the particle size is between μ and 50 μ. As an inorganic compound, the periodic table number...
, group metals, transition metals and their oxides, hydroxides, chlorides, sulfates, sulfites, carbonates, phosphates, silicates, and mixtures and complex salts of these are effective. Calcium, calcium sulfate, silicon dioxide, titanium oxide, antimony trioxide, talc, clay, aluminum oxide, calcium carbonate, carbon black, nickel powder, iron powder, zinc powder, copper powder, ferric oxide, zinc oxide, hydroxide Aluminum is preferable because it has a particularly remarkable effect of activating the vinyl monomer and strongly integrating it with the polymer. Furthermore, these can be used in the form of organosol or aqueous sol. Among these, silicon dioxide has good transparency and is therefore particularly preferred when optical properties of molded articles, particularly transparency and low haze value, are required. As the vinyl monomer used in the present invention, any ordinary vinyl monomer that can be radically polymerized can be used, but among them, methyl methacrylate has a particularly high polymerization activity, and is also highly compatible with the produced polymer and inorganic substances. It is particularly preferred because of its good coalescence properties. When using a mixture of two or more types of monomers, using methyl methacrylate as one component can be said to be a preferable application method, especially from the viewpoint of polymerization activity. According to the present invention, the concentration of sulfonic acid monomer, sulfonate monomer or carboxylic acid monomer is approximately
Used in amounts of 0.05-100% by weight. In most cases,
Sulfonic acid monomer as the monomer component increases,
Preferably, the amount of sulfonate monomer or carboxylic acid monomer is increased. The weight ratio of monomer or monomer mixture to inorganic compound used can vary within a wide range and is from about 500:1 to 1:5, preferably from about 50:1 to about 1:1. Care must be taken to ensure that the amount of the composite of inorganic fine particles and organic polymer is in the range of 0.01 to 20 parts by weight per 100 parts by weight of the monomer mixture (A). The complex is
If it is less than 0.01, the erasability will be poor, and if it exceeds 20 parts by weight, the amount of composite will be too large and the surface uniformity will be poor. The amount of organic solvent (C) used is 100 to 2000 parts by weight per 100 parts by weight of the monomer mixture (A), but it is necessary to efficiently carry out the reaction with sulfonic acid monomers, sulfonate monomers, or carboxylic acid monomers. In order to proceed well, it is preferable to coexist 10% or less water, and in some cases, a small amount of a polymerization regulator such as mercaptan, a dispersant, etc. may be used in combination. However, with regard to water, care must be taken because if it exceeds 10%, phase separation may occur from the coating material composition. The amount of organic solvents or organic solvents containing water used is
If it is less than 100 parts by weight, it will not be possible to obtain a coating with excellent smoothness and uniformity, while if it exceeds 2000 parts by weight, the film thickness will be too thin and the abrasion resistance and scratch resistance will decrease. do. Specific examples of organic solvents include alcohols such as ethanol, isopropanol, normal propanol, isobutyl alcohol, and normal butyl alcohol, aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene, ketones such as acetone, methyl ethyl ketone, and dioxane. and acid esters such as ethyl acetate, n-butyl acetate, and ethyl propionate. One or more of these organic solvents can be used as a mixture, but care must be taken in selecting the solvent and in the mixing ratio to prevent phase separation of the coating material composition. From this point of view, when a small amount of water is used, it is preferable to use an alcoholic solvent together. The reaction of a polymerization system obtained by mixing the above-mentioned specific monomer mixture (A), a sulfonic acid monomer, a sulfonate monomer, or a carboxylic acid monomer, an inorganic fine particle, a vinyl monomer, and an organic solvent is preferably carried out using, for example, nitrogen gas. It is carried out at a temperature of about 10 to 100°C, preferably 20 to 80°C, in an atmosphere of an inert gas such as. The specific reaction temperature here is selected as appropriate depending on the vinyl monomer used, but it is important to carry out the reaction at a temperature at which thermal polymerization is suppressed to a negligible level; When carried out, the integrity and homogeneity of the resulting complex is inhibited. Reaction time is 30 minutes to about 15 hours. As a means of curing the coating composition of the present invention, it is also possible to irradiate it with active energy rays such as electron beams, α rays, β rays, γ rays, etc., which are usually taken out from an electron beam accelerator of 20 to 2000 KV. However, for economical and easy curing, a wavelength of 100nm to 500nm is required.
UV radiation in the range is preferred. Of course, UV irradiation can be carried out in an inert gas such as nitrogen, carbon dioxide, or argon, but if a compound containing the specific acryloyloxy group mentioned above is used, it can be cured efficiently even in normal air. This is possible and economically the most preferable. When using ultraviolet rays as active energy rays, a photosensitizer (photocatalyst) is added to the monomer mixture (A).
It is preferable to add sensitizers such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, acetoin, butyroin, toluoin, benzyl, benzophenone,
p-Methoxybenzophenone, diethoxyacetophenone, α,α-dimethoxy-α-phenylacetophenone, methylphenylglyoxylate, ethylphenylglyoxylate, 4,4′-
Bis(dimethylaminobenzophenone), 2-hydroxy-2-methyl-1-phenylpropane-
Carbonyl compounds such as 1-one, sulfur compounds such as tetramethylthiuram monosulfide, tetramethylthiuram disulfide, azobisisobutyronitrile, azobis. Examples include azo compounds such as 2,4-dimethylvaleronitrile, and peroxide compounds such as benzoyl peroxide and ditertiarybutyl peroxide. The amount added to 100 parts by weight of monomer mixture (A) is 0.01 to 6.
Parts by weight are preferred; if too large a quantity is added, the cross-linked cured film will be colored or the weather resistance will be deteriorated, which is undesirable. If the quantity is too small, curability by ultraviolet rays will deteriorate. The above are the essential components constituting the present invention. At least one other vinyl monomer may be used in combination. In addition, stabilizers such as antioxidants, light stabilizers, thermal polymerization inhibitors, ultraviolet absorbers, colorants, etc. may be added as necessary.
A small amount may be added. If smoothness and uniformity of the coating on the surface of the obtained molded product are particularly required, it is preferable to use a silicone leveling agent whose molecular structure consists of polydimethylsiloxane units and a portion of which is polyoxygen. Those modified with an alkylene group are preferable, and the degree of modification is 1 unit of methylsiloxane group.
CH ₃ (Sio) _1/2 - with at least one oxyalkylene group (-OCH ₂ CH ₂ -,

[Formula]) is preferably bonded within a range of 0.1 to 10.0 units. If the degree of modification by oxyalkylene groups is less than 0.1, the smoothness of the film will be worse than when no silicone surfactant is added, whereas if the degree of modification by oxyalkylene groups exceeds 10, the smoothness of the film will be worse. This is not preferable because it reduces the In some cases, if a silicone leveling agent is not used, the resulting erasable molded product may become cloudy, but this can be prevented by adding a small amount of this agent. Methods such as brush coating, flow coating, spray coating, spin coating, or dip coating are adopted as methods for applying this composition, but these methods are difficult in terms of coating workability, film smoothness, and uniformity. The most preferred method is to apply by dipping. The coating amount of the coating composition on the surface of the synthetic resin molded article must be such that the thickness of the cured film is in the range of 1 to 30 microns, preferably 1.5 to 20 microns. If the thickness of the crosslinked cured film is less than 1μ, the wear resistance or surface hardness of the resulting molded product will decrease, and if it exceeds 30μ, the adhesion to the base material will decrease or cracks will occur. It becomes easier to do. Synthetic resin molded products used to produce erasable synthetic resin molded products with excellent abrasion resistance and scratch resistance using the composition of the present invention include thermoplastic resins and thermosetting resins. Various synthetic resin molded products, such as polymethyl methacrylate resin, polycarbonate resin, polyallyl diglycol carbonate resin, polystyrene resin, acrylonitrile-styrene copolymer resin (AS resin), polyvinyl chloride resin, acetate resin, ABS resin, polyester Specific examples include sheet-like molded products, film-like molded products, rod-like molded products, and various injection molded products manufactured from resins.
Among these molded products, molded products manufactured from polymethyl acrylate resin, polycarbonate resin, etc. are often used to take advantage of their properties such as optical properties, heat resistance, and impact resistance, and they also have excellent wear resistance. Since there is also a strong demand for improved weather resistance, these molded products are particularly preferred as synthetic resin molded products used in the present invention. The erasable synthetic resin molded product with excellent abrasion resistance and scratch resistance produced using the coating composition of the present invention having the above-described sticky composition is characterized by its smoothness, chemical resistance, and durability. Because of its excellent performance, it can be used in fields that require erasability, such as CRT filters, television filters, display-related products such as taximeters or digital display boards, lighting, optical products, fluorescent display tube filters, etc.
It is extremely useful for applications such as liquid crystal filters. The present invention will be explained in more detail below using Examples. Parts in Examples indicate parts by weight. In addition, the measurement evaluation in the examples was performed by the following method. (1) Scratch resistance Attach #000 steel wool to the tip of a cylinder with a diameter of 25 mm, contact it with the horizontally placed sample surface, rotate it 5 times (20 rpm) with a load of 100 g, and visually check the extent of scratches. Observe. 〇...The sample surface is hardly scratched. △...The sample surface is slightly scratched. ×...The sample surface is considerably damaged. (2) Uniformity of faded surface Based on visual judgment. 〇…Good uniformity. △...There is some unevenness. ×...poor uniformity. (3) Dispersion stability The coating material composition was placed in a cylindrical measuring cylinder and observed after standing for 24 hours. 〇…Almost no sedimentation or phase separation was observed. △...Slight sedimentation and phase separation are observed. ×... Sedimentation and phase separation are significant. Examples 1 to 8, Comparative Examples 1 and 2 The composition (D) shown in Table 1 was added to a four-necked flask reactor 1 equipped with a cooling tube, a nitrogen introduction tube, a stirring rod, and a thermocouple for detecting internal temperature. Then, nitrogen substitution was performed for 30 minutes while continuing dispersion and stirring. Furthermore, Table 1
Of the composition (D), water and monomer (SEM-Na) are
It was added when the internal temperature reached 50°C and reacted for 5 hours. After the reaction, the mixture was cooled to room temperature, and then the photosensitizer shown in Table 1 was added to prepare a coating composition. Acrylic plates of each of these coating material compositions (manufactured by Mitsubishi Rayon Co., Ltd., product name Acrylite L,
A film (2 mm thick) was immersed at a pulling rate of 1.0 cm/sec to form a film, and irradiated for 10 seconds under a 2 KW high-pressure mercury lamp at an irradiation distance of 200 mm. Table 1 shows the results obtained.
Shown below. Comparative Example 1 has the same composition as Example 1, but inorganic fine particles, SEM-Na, and solvent were added first.
The coating material composition was prepared after reacting at 50°C for 5 hours. In Comparative Example 2, inorganic fine particles were simply added and no reaction was performed.

【table】

[Table] Examples 9 to 17 Discoloration (D) in Table 2 was reacted in the same manner as in Examples 1 to 8, and after cooling, a photosensitizer was added to prepare a coating material composition. Examples 1-
The acrylic plate was immersed and cured in the same manner as in 8. The results obtained are shown in Table 2.

【table】

【table】

Claims (1)

[Scope of Claims] 1(a) 30% by weight or more of a compound having at least three (meth)acryloyloxy groups in one molecule and one to two α,β-ethylenically unsaturated bonds in one molecule A monomer mixture (A) consisting of 70% by weight or less of a compound having the following general formula (A), (b) based on 100 parts by weight of the monomer mixture (A): (In the formula, R ₁ is H, an alkyl group having 1 to 20 carbon atoms, a phenyl group and its derivatives, or a halogen atom, X is -CONH-,
[Formula] -COO(CH ₂ ) m-, or -(CH ₂ ) _o -, R ₂ and R ₃ are each H or an alkyl group having 1 to 15 carbon atoms, and R ₄ is an alkyl group having 1 to 15 carbon atoms. alkylene group, m is an integer from 1 to 20, n is an integer from 0 to 20, Y represents H, NH ₄ or an alkali metal atom) following general formula (In the formula, R ₁ is H, an alkyl group having 1 to 15 carbon atoms, COOY, a halogen atom or a phenyl group and its derivatives, R ₂ is H, an alkyl group having 1 to 15 carbon atoms, COOZ, a halogen atom or a phenyl group) and its derivatives, R ₃ is H, carbon number 1
~15 alkyl groups, halogen atoms or phenyl groups and their derivatives, X, Y, Z each represent H, NH ₄ or an alkali metal atom) or the following general formula (In the formula, R ₄ and R ₅ are each H, carbon number 1 to
At least one monomer selected from the group consisting of sulfonic acid monomers, sulfonate monomers, or carboxylic acid monomers represented by 15 alkyl groups, halogen atoms, phenyl groups, and derivatives thereof,
0.01 to 20 parts by weight of a mixture (B) of inorganic fine particles and at least one radically polymerizable vinyl monomer, and (c) 100 parts by weight of an organic solvent (C) per 100 parts by weight of the monomer mixture (A). At least one photosensitizer (E) is added to the composition (D) obtained by polymerizing the polymerization system {(A) + (B) + (C)} of ~2000 parts by weight of the monomer. body mixture (A)
An erasable coating material composition with excellent abrasion resistance, which is blended in an amount of 0.01 to 6.0 parts by weight per 100 parts by weight. 2 Compounds having at least 3 (meth)acryloyloxy groups in one molecule and 1 to 1 to 1 in 1 molecule
Polymerizable unsaturated group 1 in a monomer mixture consisting of a compound having two α,β-ethylenically unsaturated bonds
2. The erasable coating material composition with excellent abrasion resistance according to claim 1, wherein the average molecular weight per piece is 300 or less. 3 A compound having at least three (meth)acryloyloxy groups in one molecule has the following general formula (In the formula, X ₁₁ , X ₁₂ , X ₁₃ , X ₂₂ , X ₂₃ ...Xn ₂ ,
At least three of Xn ₃ and X ₁₄ are CH ₂ = CH−
COO- group and the rest are hydroxyl group, amino group, alkylene group, substituted alkylene group, etc., n
is an integer from 2 to 5) 20% by weight of at least one monomer represented by
The erasable coating material composition having excellent wear resistance according to claim 1 or 2, which contains the above. 4. The compound having at least three (meth)acryloyloxy groups in one molecule is selected from dipentaerythritol triacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, or dipentaerythritol hexaacrylate. An erasable coating material composition with excellent wear resistance according to claim 1, 2, or 3, characterized by: 5 A compound having 1 to 2 α,β-ethylenically unsaturated bonds in one molecule has one acryloyloxy group in one molecule, and has a hydroxyl group and/or
or a compound having a cyclic ether bond and/or a chain ether bond, the erasable coating material composition having excellent wear resistance according to claim 1. 6 At least one monomer selected from the group consisting of sulfonic acid monomers, sulfonate monomers, or carboxylic acid monomers is 2-acrylamido-2-methylpropanesulfonic acid, 2-
Excellent abrasion resistance as set forth in claim 1, characterized in that it is selected from sodium methacrylethanesulfonate, sodium 3-methacrylpropanesulfonate, acrylic acid, methacrylic acid, or crotonic acid. Erasable dressing composition. 7. The erasable coating material composition with excellent abrasion resistance according to claim 1, wherein the main component of the vinyl monomer is methyl methacrylate. 8 Inorganic fine particles include calcium sulfite, calcium sulfate, silicon dioxide, titanium oxide, antimony trioxide, talc, clay, aluminum oxide, calcium carbonate, carbon black, nickel powder, iron powder, zinc powder, copper powder, ferric oxide, The erasable coating material composition with excellent wear resistance according to claim 1, characterized in that the composition is at least one selected from zinc oxide and aluminum hydroxide. 9. The erasable coating material composition with excellent wear resistance according to claim 1 or 8, wherein the inorganic fine particles have a particle size of mμ to 100μ. 10. The erasable coating material composition with excellent wear resistance according to claim 1, 8, or 9, wherein the inorganic fine particles are silicon dioxide. 11. The erasable coating material composition with excellent wear resistance according to claim 1, wherein the organic solvent (C) contains 10% or less of water.