JPH09157315A - Ultraviolet-curable resin raw material composition, resin molding surface-modified therewith, and production of the molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an ultraviolet-curable resin raw material compsn. which gives a surface-modified resin molding excellent in scratch resistance and weatherability. SOLUTION: This resin raw material compsn. is prepd. by compounding 100 pts.wt. monomer mixture comprising 10-70wt.% urethane-acrylic monomer having at least two (meth)acryloyloxy groups in the molecule, 10-50wt.% acrylic monomer having at least three (meth)acryloyloxy groups in the molecule, and 5-50wt.% acrylic monomer having one (meth)acryloyloxy group and at least one kind of group selected from among hydroxyl, a cyclic ether bond, and a linear ether bond in the molecule with 5-80 pts.wt. colloidal silica and additives including an ultraviolet absorber, a hindered amine light stabilizer, a photopolymn. initiator, and a diluent.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an ultraviolet curable resin raw material composition, a resin molded product surface-modified with the resin raw material composition, and a method for producing the same. More specifically, a composition that is a raw material of an ultraviolet curable resin used for surface modification of a resin molded product, a surface-modified resin molded product having improved scratch resistance, weather resistance, hardness, adhesion, etc. It relates to a manufacturing method.

[0002]

2. Description of the Related Art In general, polycarbonate resins are excellent in properties such as transparency, moldability, heat resistance, and impact resistance, so that a wide range of applications are being developed. However, the polycarbonate resin is inherently poor in weather resistance due to its chemical structure, and the resin itself strongly yellows or deteriorates. Further, the polycarbonate resin is also inferior in scratch resistance and chemical resistance. Therefore, without applying any protective coat,
Cover lens for automobile headlight, tail lamp cover, side lamp cover, side glass, etc., or
It is difficult to use for applications such as soundproof walls of highways, and there is an increasing demand for improvement in both scratch resistance and weather resistance.

As a method for improving such problems, a coating material such as a silicone-based material, an acrylic-melamine-based material, or a urethane-based material containing an ultraviolet absorber is applied to the surface of a polycarbonate resin molded article, and a chemical reaction by heating is applied. Although a method of forming a protective coating film has been proposed by the method, it is not preferable because productivity is poor because it is a heating reaction. Therefore, in recent years, a method of forming a protective coating film by cross-linking by ultraviolet irradiation, which has high productivity, has been proposed.

However, in order to ensure the weather resistance of the polycarbonate resin, it is necessary for the coating film to absorb ultraviolet rays, and therefore it is necessary to make an ultraviolet absorber exist in the coating film. Therefore, in order to solve the problem that a coating material containing an ultraviolet absorber that inhibits curing by ultraviolet rays must be cured by ultraviolet rays, a method of forming two coats or a method of increasing the film thickness is generally taken. There is.

The second coating method is a method of forming a non-ultraviolet curable coating containing an ultraviolet absorber as the first coating, and then forming an ultraviolet curable coating having good scratch resistance and appearance on the coated surface. Is. This method makes it easy to balance the performance by assigning the functions to each film.
There are problems that the process becomes complicated, and that peeling easily occurs at the interface between the both coatings.

The method of increasing the film thickness is to increase the film thickness as much as possible to reduce the concentration of the ultraviolet absorber per unit weight so that curing inhibition by ultraviolet rays is less likely to occur and a film having a good coating surface appearance is formed. Is the way. However, since the film thickness becomes thick, the coating film tends to crack over time, and in order to prevent this, it is necessary to make the coating film somewhat flexible,
As a result, there is a problem that the scratch resistance is lowered.

Therefore, an ultraviolet curable coating capable of imparting scratch resistance and weather resistance with a one-coat system was investigated, and an ultraviolet absorber was added to a monomer mixture containing a specific polyfunctional monomer. It has been found that a cured coating having improved scratch resistance and weather resistance can be obtained by using the coating composition (JP-A-5-17706).

[0008]

However, a cured film formed from the above coating composition may show a decrease in transparency and gloss retention rate or yellowing when subjected to a long-term accelerated exposure test. In addition, the scratch resistance is not sufficient, and a coating composition capable of imparting a high level of weather resistance and scratch resistance is desired.

[0009]

Therefore, as a result of diligent studies to improve scratch resistance and weather resistance, the present inventors have found that polyfunctional urethane acrylates, polyfunctional acrylates For coating a mixture of an acrylate having a (meth) acryloyloxy group and having at least one of a hydroxyl group, a cyclic ether bond and a chain ether bond in the molecule, colloidal silica, an ultraviolet absorber, a photoinitiator and an organic solvent. It was found that the scratch resistance and the weather resistance can be improved by using the resin raw material composition, and the present invention has been completed.

That is, the present invention provides the following (a) to (h):
An ultraviolet-curable resin raw material composition comprising: (A) Urethane acrylic monomer having two or more (meth) acryloyloxy groups in one molecule 10 to 70 parts by weight (b) Acrylic monomer having three or more (meth) acryloyloxy groups in one molecule 10 50 parts by weight (c) Acrylic monomer having one (meth) acryloyloxy group in one molecule and having at least one of a hydroxyl group, a cyclic ether bond and a chain ether bond in the molecule 5 to 50 parts by weight (D) Colloidal silica composed of silica particles having a primary particle size of 1 to 200 millimicrons (a) to (c) total amount 1
5 to 80 parts by weight as solid content relative to 00 parts by weight (e) UV absorber (a) to (c) 3 to 35 parts by weight per 100 parts by weight (f) Hindered amine light stabilizer ( 0 to 10 parts by weight based on 100 parts by weight of the total amount of a) to (c) (g) 0.1 to 10 parts by weight based on 100 parts by weight of the total amount of photopolymerization initiators (a) to (c) (H) 50 to 500 parts by weight per 100 parts by weight of the total amount of the diluent solvent (a) to (g).

The present invention also provides a film thickness of 1 to 1 obtained by applying the above ultraviolet curable resin raw material composition and irradiating it with ultraviolet rays.
Provided is a resin molded article having a cured coating of 30 microns and a method for producing the same.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION In the present specification, the term “acrylic monomer” is used to include acrylate and methacrylate.

The urethane acrylic monomer as the component (a) is a (meth) acrylate having a urethane bond and is obtained by reacting an isocyanate with a (meth) acrylate having a hydroxyl group.

Examples of the isocyanate include hexamethylene diisocyanate, lysine diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, tolylene diisocyanate, xylylene diisocyanate, or diisocyanate ( For example, hydrogenated tolylene diisocyanate,
Hydrogenated xylylene diisocyanate, etc.), and hexamethylene diisocyanate, isophorone diisocyanate and dicyclohexylmethane diisocyanate are particularly preferable. In addition, examples of (meth) acrylate having a hydroxyl group include 2-hydroxyethyl (meth)
Acrylate, 2-hydroxypropyl (meth) acrylate, glycerol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, and particularly 2-hydroxyethyl (meth) acrylate. Pentaerythritol tri (meth) acrylate is preferred.

The urethane acrylic monomer contributes to the improvement of scratch resistance and weather resistance of the crosslinked and cured film. this is,
It is considered that this is because it has excellent polymerization activity when exposed to ultraviolet rays in the air.

Further, polyester urethane (meth) acrylate or polyether urethane (meth) acrylate obtained by using polyester or polyether as an initiator can also be used. Examples of the polyester include polycaprolactone having a bifunctional group or a trifunctional group, and the number average molecular weight is preferably 300 to 2000,
It is more preferably 500 to 1000. In addition, examples of the polyether include polyethylene glycol, and the number average molecular weight is preferably 100 to 2000, and more preferably 200 to 1000. By using these, the adhesion with the synthetic resin-formed product becomes better,
The weather resistance improving effect also becomes greater.

The component (a) may be used alone or in combination of two or more kinds.

The amount of component (a) used is 10 to 70 parts by weight, preferably 30 to 60 parts by weight. If it is less than 10 parts by weight, a cured coating having sufficient scratch resistance cannot be obtained. On the other hand, when it exceeds 70 parts by weight, the scratch resistance is improved, but the flexibility of the coating film is deteriorated, so that cracks are observed in the coating film over time, causing peeling and poor weather resistance.

Examples of the acrylic monomer as the component (b) include pentaerythritol tri (meth) acrylate,
Trimethylolpropane tri (meth) acrylate, trimethylolpropane ethoxy tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol monohydroxy penta (meth) acrylate include Particularly preferred are pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate and trimethylolpropane ethoxytri (meth) acrylate. The component (b) may be used alone or in combination of two or more kinds.

The component (b) contributes to the improvement of scratch resistance.
It is considered that this is because the acrylic group in the uncured portion is almost eliminated by using the mixture with the component (a).

The amount of component (b) used is in the range of 10 to 50 parts by weight, preferably 20 to 45 parts by weight.
When the amount is less than 10 parts by weight, the scratch resistance is not improved. If it exceeds 50 parts by weight, the scratch resistance is lowered.

Examples of the acrylic monomer as the component (c) include 2-hydroxyethyl (meth) acrylate, caprolactone-modified 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate,
Glycidyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, caprolactone-modified tetrahydrofurfuryl (meth) acrylate, ethoxyethyl (meth) acrylate, ethylcarbitol (meth)
Acrylate and tetrahydrofurfuryloxyethyl (meth) acrylate are mentioned. In particular, 2-hydroxyethyl (meth) acrylate, caprolactone-modified 2-hydroxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, caprolactone-modified tetrahydrofurfuryl (meth) acrylate and tetrahydrofurfuryloxyethyl (meth) acrylate are preferable. The component (c) may be used alone or in combination of two or more kinds. The cyclic ether bond means an ether bond existing in the ring, and the chain ether bond means another ether bond.

The component (c) is a component necessary for imparting adhesion to the polycarbonate resin molded product, and also a component for imparting smoothness and flexibility of the cured film.

The amount of component (c) used is in the range of 5 to 50 parts by weight, preferably 10 to 40 parts by weight. 5
If it is less than 50 parts by weight, the adhesion of the cured film is insufficient, and if it exceeds 50 parts by weight, a cured film having sufficient scratch resistance cannot be obtained.

The colloidal silica composed of silica particles having a primary particle diameter of 1 to 200 millimicrons as the component (d) can be used as a colloidal solution or as a powdery colloidal silica containing no dispersion medium. As a dispersion medium for the colloidal silica solution, water, methanol,
Ethanol, isopropanol, n-butanol, n-
Alcohols such as propanol, polyhydric alcohols such as ethylene glycol, polyhydric alcohol derivatives such as ethyl cellosolve and butyl cellosolve, methyl ethyl ketone, methyl isobutyl ketone, ketones such as diacetone alcohol, 2-hydroxyethyl acrylate,
Acrylates such as 2-hydroxypropyl acrylate and tetrahydrofurfuryl acrylate and general organic solvents can be used, but alcohols having 1 to 4 carbon atoms are preferably used. The dispersion medium may be the same as the above-mentioned component (c) or the following (h) component. The amount of the dispersion medium is usually 100 to 900 parts by weight with respect to 100 parts by weight of colloidal silica (solid content).

As these colloidal silica, those produced by a well-known method and commercially available can be used.
It is necessary to use particles having a particle size of 1 to 200 millimicrons, and particularly preferably 5 to 80 millimicrons. If the particle size is less than 1 millimicron, the stability of the dispersed state is poor and it is difficult to obtain a uniform quality, and if the particle size exceeds 200 millimicrons, the transparency of the coating is poor and turbidity occurs. I can only get the big one.

The colloidal silica is available in an acidic or basic form, but it is more preferable to use the acidic form in the present invention.

Colloidal silica significantly improves the scratch resistance and surface hardness of the cured coating.

The compounding ratio of colloidal silica is from (a) to
5 to 80 parts by weight per 100 parts by weight of the total amount of (c),
Preferably it is 10 to 60 parts by weight. When the blending ratio is less than 5 parts by weight, the scratch resistance of the cured film is insufficient, and conversely, when it is used in excess of 80 parts by weight, cracking and deterioration of adhesion are observed in the cured film. Become. In addition,
The ratio of colloidal silica is a value as a solid content of silica particles.

The ultraviolet absorber as the component (e) is not particularly limited, and any one can be used as long as it is uniformly dissolved in the ultraviolet curable resin raw material composition and has good weather resistance. However, from the viewpoint of good solubility and weather resistance improvement for the composition of the present invention, benzophenone-based, benzotriazole-based, phenyl salicylate-based, or,
A UV absorber which is a compound derived from phenyl benzoate and has a maximum absorption wavelength in the range of 240 to 380 nm is preferable.

Specific examples include 2-hydroxybenzophenone, 5-chloro-2-hydroxybenzophenone,
2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-
n-octoxybenzophenone, 4-dodecyloxy-2
-Hydrobenzophenone, 2-hydroxy-4-octadecyloxybenzophenone, 2,2'-dihydroxy-
4-methoxybenzophenone, 2,2'-dihydroxy-4,4-dimethoxybenzophenone, 2,2 ', 4
4'-tetrahydroxybenzophenone, phenyl salicylate, p-tert-butylphenyl salicylate, p- (1,1,3,3-tetramethylbutyl) phenyl salicylate, 3-hydroxyphenylbenzoate, phenylene 1,3-dibenzoate, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl)
Phenyl] -2H-benzotriazole, 2- (2-hydroxy-5-methylphenyl) benzotriazole,
2- (2-hydroxy-5-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-3,5-di-tert-butylphenyl) benzotriazole, 2- (2-hydroxy-5) -Tert
-Butylphenyl) benzotriazole, 2- (2-hydroxy-4-octyloxyphenyl) benzotriazole, methyl-3- [3-tert-butyl-5- (2
H-benzotriazol-2-yl) -4-hydroxyphenyl] propionate condensate of polyethylene glycol (number average molecular weight of about 300), ethanediamide-
N- (2-ethoxyphenyl) -N '-(4-isododecylphenyl)-(anilide oxalate), and ethanediamide-N- (2-ethoxyphenyl) -N'-
(2-ethylphenyl)-(anilide oxalic acid) and the like can be mentioned.

Particularly, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2
-(2-hydroxy-5-tert-butylphenyl)
Benzotriazole, methyl-3- [3-tert-butyl-5- (2H-benzotriazol-2-yl)-
Condensation product of 4-hydroxyphenyl] propionate and polyethylene glycol (number average molecular weight of about 300), ethanediamide-N- (2-ethoxyphenyl) -N'-
(4-isododecylphenyl)-(anilide oxalate) and ethanediamide-N- (2-ethoxyphenyl) -N '-(2-ethylphenyl)-(anilide oxalate) are preferred.

These ultraviolet absorbers may be used alone or in combination of two or more kinds.

The component (e) is added in an amount of 3 to 35 parts by weight, preferably 5 to 20 parts by weight, based on 100 parts by weight of the total amount of (a) to (c). If it is less than 3 parts by weight, the effect of improving the weather resistance is not sufficient, and if it exceeds 35 parts by weight, the curability of the crosslinked cured coating is lowered and the scratch resistance becomes insufficient.

As the hindered amine light stabilizer as the component (f), known ones can be used. Specific examples include 4-pezoyloxy-2,2,6,6-tetramethylpiperidine, 4-hexanoyloxy-2,2,6,6-tetramethylpiperidine, 4-octanoyloxy-2,2.
6,6-Tetramethylpiperidine, 4-stearoyloxy-2,2,6,6-tetramethylpiperidine, succinic acid-bis (2,2,6,6-tetramethylpiperidine), sabacic acid-bis (2,2 2,6,6-tetramethylpiperidine), sabacinic acid-bis (1,2,2,6)
6-pentamethyl-4-piperidine), 8-acetyl-
3-dodecyl-7,7,9,9-tetramethyl-1,
3,8-Triazaspiro [4,5] decane-2,4-dione, N-methyl-3-dodecyl-1- (2,2,6
6-tetramethyl-4-piperidinyl) pyrrolidine-
2,5-dione, N-acetyl-3-dodecyl-1-
(2,2,6,6-tetramethyl-4-piperidinyl)
Pyrrolidine-2,5-dione, phthalic acid-bis (1,
2,2,6,6-pentamethyl-4-piperidine), trimesic acid-tris (2,2,6,6-tetramethyl-
4-piperidyl) and the like. These hindered amine light stabilizers may be used alone or in combination of two or more.

The amount of component (f) added is 0 to 10 parts by weight, preferably 1 to 5 parts by weight, based on 100 parts by weight of the total amount of (a) to (c). If it exceeds 10 parts by weight, the scratch resistance of the coating may be reduced or the coating may be yellowed.

As the photopolymerization initiator as the component (g), known ones used for ultraviolet curing can be used. Specific examples include 2-hydroxy-2-methyl-1-phenylpropan-1-one and 1- (4-isopropylphenyl) -2.
-Hydroxy-2-methylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, benzoin,
Benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, acetoin, butyroin, toluoin, benzyl, benzophenone, p-methoxybenzophenone, 2,2-diethoxyacetophenone, α, α-
Diethoxy-α-phenylacetophenone, methylphenylglyoxylate, ethylphenylgluoxylate, 4,4′-bis (dimethylaminobenzophenone), azobisisobutyronitrile, azobis-2,4
-Azo compounds such as dimethylvaleronitrile, peroxide compounds such as benzoin peroxide, 2,
Examples thereof include acylphosphine oxide such as 4,6-trimethylbenzoylphenylphosphine oxyside.

The amount of component (g) added is 0.1 to 10 parts by weight, preferably 1 to 6 parts by weight, based on 100 parts by weight of the total amount of (a) to (c). If it is less than 0.1 parts by weight, the curing by ultraviolet rays will be poor. If it exceeds 10 parts by weight, a yellowish color of the cured film may occur or weather resistance may be deteriorated.

The diluting solvent for the component (h) is not particularly limited as long as it can dissolve the above components, and specific examples include ethanol, isopropyl alcohol, n-propyl alcohol, isobutyl alcohol, n-butyl alcohol. Alcohols such as, aromatic hydrocarbons such as benzene, toluene, xylene, ketones such as acetone and methyl ethyl ketone, ethers such as dioxane,
Examples thereof include esters such as ethyl acetate and n-butyl acetate, polyhydric alcohol derivatives such as methyl cellosolve, ethyl cellosolve and butyl cellosolve, and methoxybutanol and methoxypropanol. These organic solvents may be used alone or in combination of two or more.

The amount of the component (h) used is the components (a) to (g).
50 to 500 parts by weight based on 100 parts by weight of the mixture. If the amount is less than 50 parts by weight, a film having excellent smoothness and uniformity cannot be obtained. When it exceeds 500 parts by weight, the film thickness of the coating becomes too thin, resulting in poor scratch resistance and weather resistance.

The ultraviolet-curable composition of the present invention contains, if necessary, stabilizers such as antioxidants and thermal polymerization inhibitors, leveling agents, defoamers, thickeners, antistatic agents, antifog agents. An additive such as an adhesion improver may be added.

As a method of applying the composition of the present invention,
Known methods such as flow coating, spin coating, spray coating, brush coating and dip coating are used.

The coating amount of the composition is such that the film thickness of the cured film is 1 to
It is in the range of 30 microns, preferably 3 to 10
It is in the range of micron. If the film thickness is less than 1 micron, sufficient surface hardness, scratch resistance and weather resistance cannot be obtained. If it exceeds 30 microns, the curing tends to be insufficient, or the cured coating tends to crack.

A method of irradiating ultraviolet rays is used as a means for curing the coating film applied to the surface of the resin molded product.
As a light source for generating ultraviolet rays, an ultraviolet lamp is generally used in terms of practicality and economy. Specific examples thereof include a low pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a xenon lamp, and a metal halide lamp. The dose of ultraviolet rays is appropriately selected according to the composition of the composition, the shape of the resin molded body, etc., but usually 500 to 20.
It is 00 mJ / cm ² .

The ultraviolet irradiation atmosphere may be of course in an inert gas such as nitrogen, carbon dioxide or argon, but the coating composition of the present invention can be efficiently cured even in a normal atmosphere, which is economical. Air is the most preferred atmosphere.

The composition of the present invention is particularly suitable for producing a polycarbonate resin molded article having excellent scratch resistance and weather resistance, but other synthetic resin molded articles such as thermoplastic resin and thermosetting resin. Molded products of various synthetic resins such as resin, specifically polymethylmethacrylate resin, polyallyldiglycolcarbonate resin, polystyrene resin, acrylonitrile-styrene copolymer resin (AS resin), polyvinyl chloride resin, acetate resin, ABS resin It can also be used for imparting scratch resistance and weather resistance to molded articles and the like manufactured from polyester resin, polymethacrylimide resin, polyamide resin and the like.

[0047]

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In Examples and Comparative Examples,
“Parts” are based on weight. Further, the evaluation of the properties in Examples and Comparative Examples was performed by the following methods.

1. Scratch resistance (Taber abrasion test): abrasion is carried out under the conditions of a wear wheel CS-10F, a load of 500 g, and an abrasion count of 500 cycles, and the haze value is measured using a haze meter. The scratch resistance is indicated by (haze value after scratching-haze value before scratching).

2. Adhesion: Scratches reaching the base material of the molded product with a razor are placed on the surface of the sample at 11 mm and 11 mm intervals in the vertical and horizontal directions to make 100 squares and press the cellophane tape (made by Nichiban) on the squares. And sharply peel it upward. Adhesion is evaluated by [Number of remaining cells / total number of cells (1
00)].

3. Appearance: (1) Transparency: Measure haze value using a haze meter. (2) Crack: Visually observed, and ◯: No crack is generated, Δ: Some cracks are present, and X: Innumerable cracks are present.

4. Weather resistance: UV irradiation 10 using QUV (dew panel UV fluorescent lamp weather meter)
Time (atmosphere temperature 60 ° C), condensation 2 hours (atmosphere temperature 5
(0 ° C.) as one cycle, a 900-hour accelerated exposure test is performed, and the exposed final sample is evaluated for adhesion and yellowing degree of the coating. Adhesion is evaluated according to the above item 2. The degree of yellowing is measured by measuring the degree of yellowing using a color difference meter and is represented by (yellowing degree after accelerated exposure test−yellowness degree before accelerated exposure test).

[Examples 1 to 9 and Comparative Examples 1 to 4] Polycarbonate resin plates (3 mm in thickness, Stella S300 manufactured by Mitsubishi Plastics) were coated with the ultraviolet-curable resin raw material compositions having the compositions shown in Tables 1 and 2 below. After coating with a spin coater to form a film, use a high pressure mercury lamp in an air atmosphere for 10
It was irradiated with ultraviolet rays of 00 mJ / cm ² . A resin plate having a coating with a cured film thickness of 5 μm was obtained.

Each of the obtained samples was evaluated for scratch resistance, adhesion, appearance and weather resistance. The evaluation results are shown in Table-1 and Table-2.

[0054]

[Table 1]

[0055]

[Table 2]

* 1: urethane acrylate synthesized from hexamethylene diisocyanate and pentaerythritol triacrylate, * 2: pentaerythritol triacrylate, * 3: urethane acrylate synthesized from polycaprolactone, hexamethylene diisocyanate and pentaerythritol triacrylate [polycaprolactone : Pracel 305 manufactured by Daicel Chemical Industries, Ltd., * 4: Tetrahydrofurfuryl acrylate (THF-A manufactured by Osaka Organic Chemical Industry), * 5: Caprolactone-modified tetrahydrofurfuryl acrylate (TC-110S manufactured by Nippon Kayaku), * 6: 2 -(2-Hydroxy-5-tert-butylphenyl) benzotriazole (Tinuv manufactured by Ciba-Geigy)
in PS), * 7: 2,4-dihydroxybenzophenone, * 8: Hindered amine light stabilizer (Sandu
vor) 3058), * 9: 2-hydroxy-2-methyl-phenylpropan-1-one, * 10: colloidal silica in isopropanol (S).
iO ₂ solid content, 30% by weight, Nissan Kagaku IPA-S
T), * 11: ethyl acetate, * 12: isopropanol, * 13: urethane acrylate synthesized from isophorone diisocyanate and pentaerythritol triacrylate (Ebecryl 8301 manufactured by UCB), * 14: isocyanurate consisting of hexamethylene diisocyanate and pentafunctional. Urethane acrylate (“U-15HA” manufactured by Shin-Nakamura Chemical Co., Ltd.) synthesized from the above-mentioned acrylic group and an oligomer having one hydroxyl group.

[0057]

The surface-modified resin molded product obtained by using the ultraviolet-curable resin raw material composition of the present invention is not only excellent in scratch resistance and weather resistance, but also the adhesion of the coating film to the substrate. It is also excellent for automobile parts that are strongly required to have durability and weather resistance, especially applications such as lens covers for headlights, tail lamps or side glasses, and
It is useful for applications such as noise barriers on highways.

Claims (7)

[Claims] 1. An ultraviolet-curable resin raw material composition comprising the following (a) to (h): (A) Urethane acrylic monomer having two or more (meth) acryloyloxy groups in one molecule 10 to 70 parts by weight (b) Acrylic monomer having three or more (meth) acryloyloxy groups in one molecule 10 50 parts by weight (c) Acrylic monomer having one (meth) acryloyloxy group in one molecule and having at least one of a hydroxyl group, a cyclic ether bond and a chain ether bond in the molecule 5 to 50 parts by weight (D) Colloidal silica composed of silica particles having a primary particle size of 1 to 200 millimicrons (a) to (c) total amount 1
5 to 80 parts by weight as solid content relative to 00 parts by weight (e) UV absorber (a) to (c) 3 to 35 parts by weight per 100 parts by weight (f) Hindered amine light stabilizer ( 0 to 10 parts by weight based on 100 parts by weight of the total amount of a) to (c) (g) 0.1 to 10 parts by weight based on 100 parts by weight of the total amount of photopolymerization initiators (a) to (c) (H) 50 to 500 parts by weight per 100 parts by weight of the total amount of the diluent solvent (a) to (g). 2. The acrylic monomer of (c) is a compound selected from the group consisting of tetrahydrofurfuryl (meth) acrylate and a derivative of tetrahydrofurfuryl (meth) acrylate. Ultraviolet curable resin raw material composition. 3. The ultraviolet-curable resin raw material composition according to claim 1, wherein the diluent solvent (h) is a diluent solvent selected from the group consisting of ethyl acetate and isopropanol. 4. A cured coating having a film thickness of 1 to 30 μm, which is obtained by applying the ultraviolet curable resin raw material composition according to claim 1 and irradiating with ultraviolet rays. Resin molded product. 5. The resin molded product according to claim 4, which is made of polycarbonate. 6. The ultraviolet-curable resin raw material composition according to claim 1 is applied to the surface of a resin molded article and irradiated with ultraviolet rays to form a cured film having a thickness of 1 to 30 microns. A method for producing a surface-modified resin molded article, comprising: 7. The method according to claim 6, wherein the resin molded product is made of polycarbonate.