JP3207926B2 - Antistatic hard coating agent and synthetic resin molded article using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photocurable resin composition which forms a cured film having excellent antistatic properties, adhesion and moisture resistance by irradiation with active energy rays such as ultraviolet rays, and this photocurable resin composition. The present invention relates to a synthetic resin molded article having a cured film obtained by using the method.

[0002]

2. Description of the Related Art Synthetic resins are lighter than glass products.
In addition to excellent properties such as toughness, it has advantages such as low cost and easy processing, and is used in a wide range of fields such as automobile parts, optical lenses, optical disks, organic plate glass, and signboards. However, these synthetic resins have the drawback that they are easily scratched, and are liable to be charged because they are easily charged. In order to improve these drawbacks, various methods have been studied for forming a crosslinked cured film on the surface of a synthetic resin by applying a photocurable resin composition and curing the composition with ultraviolet irradiation. However, although the abrasion resistance is improved by the above-mentioned method, there is a problem that it is easily charged due to friction or the like, and dust or the like adheres to the aesthetic appearance. Therefore, various methods for adding an antistatic agent to the photocurable resin composition have been proposed to improve these disadvantages.

[0003]

However, in the method of adding an antistatic agent to a photocurable resin composition, when various surfactants such as cations, anions and nonionics are added as an antistatic agent, When a salt such as an alkali metal salt, an alkaline earth metal salt, and an ammonium salt is added as an antistatic agent, it is necessary to increase the addition amount in order to obtain a sufficient antistatic property. In this case, there is a problem that the antistatic agent bleeds on the surface of the cured film.

[0004]

The inventors of the present invention have conducted intensive studies and have found that one or more salts selected from among alkali metal salts, alkaline earth metal salts and ammonium salts as an antistatic agent and an imidazoline surfactant. When used together, a photocurable resin composition containing a small amount of these is applied to an article, for example, a synthetic resin molded article, and when the coating film obtained is cured by irradiation with active energy rays such as ultraviolet rays, the appearance and adhesion are Naturally, the inventors have found that a cured film excellent in antistatic properties and moisture resistance is formed despite the small amount of the antistatic agent, and completed the present invention.

That is, the present invention relates to a photocurable resin composition containing an antistatic agent, wherein the antistatic agent comprises one or more salts selected from the group consisting of an alkali metal, an alkaline earth metal salt and an ammonium salt, and an imidazoline type. A photocurable resin composition characterized by being used in combination with a surfactant, and a cured film obtained by applying the photocurable resin composition to the surface of a synthetic resin molded article and irradiating it with active energy rays. The present invention relates to a synthetic resin molded product.

A photocurable resin composition is a (meth) acrylate oligomer having at least two (meth) acryloyloxy groups in one molecule (hereinafter simply referred to as (meth) acrylate).
At least one compound having a (meth) acryloyloxy group such as a (meth) acrylate monomer having at least one (meth) acryloyloxy group in one molecule (hereinafter, simply referred to as a (meth) acrylate monomer). It contains a seed as a resin component.

[0007] One or more (meth) acrylate oligomers can be used. Examples of the (meth) acrylate oligomer include a polyfunctional urethane (meth) acrylate, a polyfunctional urethane (meth) acrylate oligomer, a polyfunctional polyester (meth) acrylate oligomer, and a polyfunctional epoxy (meth) acrylate oligomer.

Examples of the polyfunctional urethane (meth) acrylate include a urethanization reaction product of a (meth) acrylate monomer having at least one (meth) acryloyloxy group and a hydroxyl group in one molecule with a polyisocyanate. . Examples of the polyfunctional urethane (meth) acrylate oligomer include an isocyanate compound obtained by reacting a polyol with a polyisocyanate and a (meth) acrylate monomer having at least one (meth) acryloyloxy group and a hydroxyl group in one molecule. And urethanation reaction products.

The acrylate monomer having at least one (meth) acryloyloxy group and hydroxyl group in one molecule used in the urethanization reaction includes 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl acrylate, glycerin di (meth) acrylate, trimethylolpropane diacrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate Can be

The polyisocyanate used in the urethanization reaction includes hexamethylene diisocyanate, lysine diisocyanate, isophorone diisocyanate,
Dicyclohexylmethane diisocyanate, tolylene diisocyanate, xylylene diisocyanate, diisocyanates obtained by hydrogenating aromatic isocyanates among these diisocyanates (for example, diisocyanates such as hydrogenated tolylene diisocyanate and hydrogenated xylylene diisocyanate), triphenylmethane Examples thereof include di- or tri-polyisocyanates such as triisocyanate and dimethylenetriphenyltriisocyanate, and polyisocyanates obtained by multiplying diisocyanates.

As the polyols used in the urethanization reaction, generally used are aromatic, aliphatic and alicyclic polyols, as well as polyester polyols and polyether polyols. Usually, aliphatic and alicyclic polyols include 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, ethylene glycol, propylene glycol, trimethylolethane,
Examples include trimethylolpropane, dimethylolheptane, dimethylolpropionic acid, dimethylolbutyrionic acid, glycerin, hydrogenated bisphenol A, and the like.

The polyester polyol is obtained by a dehydration condensation reaction between the polyol and a polybasic carboxylic acid (anhydride). Specific compounds of polybasic carboxylic acids include (anhydrous) succinic acid, adipic acid, (anhydrous) maleic acid, (anhydrous) trimellitic acid, hexahydro (anhydride) phthalic acid, (anhydrous) phthalic acid, isophthalic acid, Terephthalic acid; Examples of the polyether polyol include a polyoxyalkylene glycol, and a polyoxyalkylene-modified polyol obtained by reacting the polyol or phenol with an alkylene oxide.

The polyfunctional polyester (meth) acrylate oligomer is obtained by a dehydration condensation reaction of (meth) acrylic acid, polybasic carboxylic acid (anhydride) and polyol. The polybasic carboxylic acids (anhydrides) used in the dehydration condensation reaction include (anhydride) succinic acid, adipic acid, (anhydride) maleic acid, (anhydride) itaconic acid, (anhydride) trimellitic acid, and (anhydro) pyromellitic Acid, hexahydro (anhydride) phthalic acid, (phthalic anhydride), isophthalic acid, terephthalic acid and the like. The polyol used for the dehydration condensation reaction includes 1,4-butanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol, propylene glycol, neopentyl glycol, dimethylol heptane,
Examples include dimethylolpropionic acid, dimethylolbutyrionic acid, trimethylolpropane, ditrimethylolpropane, pentaerythritol, dipentaerythritol and the like.

The polyfunctional epoxy (meth) acrylate oligomer is obtained by an addition reaction between polyglycidyl ether and (meth) acrylic acid. As polyglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether,
Tripropylene glycol diglycidyl ether, 1,
Examples thereof include 6-hexanediol diglycidyl ether and bisphenol A diglycidyl ether.

[0015] One or more (meth) acrylate monomers can be used. Examples of the (meth) acrylate monomer include a polyfunctional (meth) acrylate monomer having at least two (meth) acryloyloxy groups in one molecule (hereinafter, referred to as a polyfunctional (meth) acrylate monomer) and one in one molecule. (Meth) acryloyloxy group-containing monofunctional acrylate monomer (hereinafter referred to as monofunctional acrylate monomer).

The polyfunctional (meth) acrylate monomers include dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, and pentaerythritol Tri (meth) acrylate,
Pentaerythritol di (meth) acrylate, ditrimethylolpropanetetra (meth) acrylate, ditrimethylolpropanetri (meth) acrylate, ditrimethylolpropanedi (meth) acrylate, trimethylolpropanetri (meth) acrylate, trimethylolpropanedi (meth) ) Acrylate, 1,1,1-
Tris (acryloyloxyethoxyethoxy) propane, 2,2-bis (4-acryloyloxyethoxyethoxyphenyl) propane, 2,2-bis (4-acryloyloxyethoxyethoxycyclohexyl) propane, 2,2-bis (4-acryloyl) (Oxyethoxyethoxyphenyl) methane, neopentyl glycol di (meth) acrylate, hydrogenated dicyclopentadienyl di (meth) acrylate, tris (hydroxyethyl) isocyanurate triacrylate, tris (hydroxyethyl) isocyanurate diacrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, isobornyl di (meth) acrylate, polyethylene glycol di (meth) acrylate, Propylene glycol di (meth) acrylate, polyalkylene glycol di (meth) acrylates such as polytetramethylene glycol di (meth) acrylate.

As monofunctional (meth) acrylate monomers, tetrahydrofurfuryl acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, hydroxypropyl (meth) acrylate, 2-hydroxy-3-phenoxy In addition to propyl acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, trimethylolpropane mono (meth) acrylate, and pentaerythritol mono (meth) acrylate, 2- (meth) acrylate monomers containing a carboxyl group are particularly preferred. (Meth) acryloyloxyethyl phthalic acid,
2- (meth) acryloyloxyethyl hexahydrophthalic acid, carboxylethyl (meth) acrylate, 2
-(Meth) acryloyloxyethyl succinic acid, N-methacryloyloxy-N ', N'-dicarboxy-p-
Examples thereof include phenylenediamine and 4-methacryloyloxyethyl trimellitic acid. Further, the monofunctional (meth) acrylate monomer includes a vinyl group-containing monomer such as N-vinylpyrrolidone and a (meth) acryloylamino group-containing monomer such as 4-methacryloylamino-1-carboxymethylpiperidine.

The alkali metal salt, alkaline earth metal salt and ammonium salt include chlorides, bromides, iodides, borofluorides, perchlorates, thiocyanates of lithium, sodium, potassium, calcium, ammonium and the like. There are nitrates, fluorinated sulfonates and the like, specifically, lithium chloride, lithium bromide, sodium bromide, lithium iodide, sodium iodide, potassium iodide, lithium thiocyanate, sodium thiocyanate, ammonium thiocyanate, Lithium perchlorate, sodium perchlorate, potassium perchlorate, calcium perchlorate, lithium trifluoromethanesulfonate, sodium trifluoromethanesulfonate, potassium trifluoromethanesulfonate, lithium borofluoride, sodium borofluoride, hexafluoro Phosphoric acid Umm, and the like.

The imidazoline surfactants include 1-
Hydroxyethyl-2-laurylimidazoline, 1-aminoethyl-2-laurylimidazoline, 1-hydroxyethyl-2-myristylimidazoline, 1-aminoethyl-2-myristylimidazoline, 1-hydroxyethyl-2-palmitylimidazoline, 1 -Aminoethyl-2-palmicylimidazoline, 1-hydroxyethyl-2-oleylimidazoline, 1-aminoethyl-2-
Oleimidazoline, 1-hydroxyethyl-2-stearylimidazoline, 1-aminoethyl-2-stearylimidazoline and the like. Preferably, 1-hydroxyethyl-2-alkylimidazolines are used.

Next, the content ratio of one or more salts selected from the group consisting of alkali metal salts, alkaline earth metal salts and ammonium salts of the present invention and the imidazoline surfactant to the photocurable resin composition will be described in detail. The amount of one or more salts selected from the group consisting of alkali metal salts, alkaline earth metal salts and ammonium salts is 0.05 to 5 parts by weight per 100 parts by weight of the resin component of the photocurable resin composition.
Parts by weight, preferably 0.1 to 3 parts by weight. When the amount is less than 0.05 part by weight, sufficient antistatic properties are not exhibited. When the amount exceeds 5 parts by weight, compatibility with the resin component is deteriorated, and a problem is caused in the surface curability. The amount of the imidazoline surfactant used is 0.1 to 6 parts by weight, preferably 0.5 to 4 parts by weight, based on 100 parts by weight of the resin component of the photocurable resin composition. When the amount is less than 0.1 part by weight, sufficient antistatic properties are not exhibited, and when the amount exceeds 6 parts by weight, a problem is caused in the surface curability, which is not good. The total amount of the salt selected from the group consisting of alkali metal salts, alkaline earth metal salts and ammonium salts and the imidazoline surfactant is 7 parts by weight or less based on 100 parts by weight of the resin component of the photocurable resin composition. , Preferably 2 to 6 parts by weight. When a salt selected from the group consisting of an alkali metal salt, an alkaline earth metal salt and an ammonium salt and an imidazoline-type surfactant are used, a synergistic effect is obtained in improving the antistatic property, and therefore they are always used together. When a carboxyl group-containing (meth) acrylate oligomer and a carboxyl group-containing (meth) acrylate monomer are used as the resin component used in the photocurable resin composition, the antistatic property is further improved. Monomers are preferred.

One or more photosensitizers can be added to the photocurable resin composition of the present invention. Examples of the photosensitizer include benzoin, benzoin ethyl ether, benzoin butyl ether, benzoin isopropyl ether, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, benzophenone, benzyl, benzyldimethyl ketal, Diethoxyacetophenone, xanthone, thioxanthone, azobisisobutyronitrile,
Examples include benzoyl peroxide and other generally known photosensitizers. Generally speaking, the amount of the photosensitizer is 0.01 to 1 based on 100 parts by weight of the resin component.
It is used in the range of 0 parts by weight, but preferably 1 to 5 parts by weight. When the amount of the photosensitizer is less than 0.01 part by weight, curing is insufficient. When the amount exceeds 10 parts by weight, a problem such as coloring of the cured film is generally caused.

The photocurable resin composition of the present invention may contain a solvent. Examples of the solvent include alcohols such as ethanol, propanol, isopropanol and butanol, aromatic hydrocarbons such as toluene and xylene, acetates such as ethyl acetate and butyl acetate, acetone,
Ketones such as methyl ethyl ketone and ethers such as 2- (2-ethoxyethoxy) ethanol (hereinafter referred to as ethyl cellosolve), 2-methoxyethanol, 2-ethoxyethanol and 1,4-dioxane are used.

Further, paint additives such as a light stabilizer, an antioxidant, an ultraviolet absorber, an antifoaming agent and a leveling agent may be added to the photocurable resin composition of the present invention. As the base material of the synthetic resin molded article on which the photocurable resin composition of the present invention is applied to the surface, a thermoplastic resin and a thermosetting resin are used without distinction. For example, polymethyl methacrylate (acrylic resin), polycarbonate, ABS Resin, polystyrene, polyvinyl chloride, polyester resin, acetate resin, epoxy resin, unsaturated polyester resin and the like are used. A known method such as brush coating, spray coating, roll coating, dipping, or spin coating may be used as appropriate.

[0024]

EXAMPLES The present invention will be described in more detail with reference to the following examples, which are illustrative only and the present invention is not limited to these examples. Synthesis Example 1 168 g of hexamethylene diisocyanate (Desmodur H; manufactured by Sumitomo Bayer Urethane Co., Ltd.) was placed in a 2-liter glass reactor equipped with a stirrer, a thermometer, and a dropping funnel.
CO equivalent = 2), 0.8 g of hydroquinone monomethyl ether as a polymerization inhibitor, and 0.25 g of dibutyltin dilaurate as a catalyst, and a branch-type polyester polyol (desmophen 6
80; OH% = 2) 816, manufactured by Sumitomo Bayer Urethane Co., Ltd.
g (OH equivalent = 0.96) was added dropwise over 1 hour, and the reaction was continued for 2 hours. Then, pentaerythritol acrylate (PET-30; Nippon Kayaku, OH value = 124) 474
g (OH equivalent = 1.05) was added dropwise over 1 hour.
Then, after continuing the reaction at the same temperature for 2 hours to complete the reaction,
1457 g of a polyfunctional urethane acrylate oligomer was obtained. Subsequent analysis did not detect any isocyanate.

Synthesis Example 2 Pentaerythritol acrylate (PE) was placed in a 2-liter glass reactor equipped with a stirrer, thermometer, and dropping funnel.
T-30; Nippon Kayaku, OH value = 124) 952 g (O
H equivalent = 2.1), 0.8 g of hydroquinone monomethyl ether as a polymerization inhibitor, and 0.25 g of dibutyltin dilaurate as a catalyst, and 168 g of hexamethylene diisocyanate (N
(CO equivalent = 2) was added dropwise over 1 hour. Next, the reaction was continued at the same temperature for 2 hours to complete the reaction, and 1120 g of polyfunctional urethane acrylate was obtained. Subsequent analysis did not detect any isocyanate.

Synthesis Example 3 In a 1-liter glass reactor equipped with a stirrer, a thermometer and a water separator, 127 g (0.5 mol) of dipentaerythritol, 38 g (0.26 mol) of adipic acid and 187 g of acrylic acid were placed. (2.6 mol), 127 g of toluene, and sulfuric acid 0.1 g.
6 g, copper sulfate 0.5 g, and hydroquinone monomethyl ether 0.03 g were charged. The reaction was carried out under reflux while stirring and blowing air, and the outflowing toluene and water azeotrope were separated from water after cooling, and the toluene was returned to the reaction system and reacted, and 52 cc of water was distilled off. Then, the reaction solution was cooled, a mixed solvent of toluene: cyclohexane (5: 1) was added, and the mixture was neutralized with a 10% aqueous solution of caustic soda, and then separated, and the oil layer was washed with 10% saline. After the oil layer was dried over anhydrous magnesium sulfate, the mixed solvent of toluene and cyclohexane was removed under reduced pressure at 50 to 60 ° C. to obtain 300 g of a pale yellow polyfunctional polyester acrylate oligomer as a residue.

Synthesis Example 4 Novolak type epoxy resin (epoxy equivalent: 215) 53
7.5 g (2.5 equivalents) and 189 g of acrylic acid (2.
625 mol) was placed in a 1-liter glass reactor, 7.3 g of tetrabutylammonium bromide was added, and the mixture was reacted at 90 ° C. for 6 hours to obtain 726.5 g of a polyfunctional epoxy acrylate oligomer.

Example 1 An acrylic resin extruded plate was applied to a coating solution prepared by adjusting the photocurable resin composition composed of the components shown in Tables 1 and 2 to 40% with ethyl cellosolve by dipping.
After a film was formed and dried at 60 ° C. for 5 minutes, the resin plate was dried in air with a high-pressure mercury lamp (UVC-2534, manufactured by Ushio Inc.).
/ 1MNLC3-AA06), and irradiated with ultraviolet rays from a distance of 150 mm at 80 W / cm at a conveyor speed of 2 m / min. The appearance of the obtained sample is good, adhesion (Note 1) is 100/100, steel wool hardness B (Note 2), surface resistance value (Note 3) is 6.5 × 10 ¹¹ Ω, ash adhesion test ( In Note 4), no ash was attached. After leaving the sample in a constant temperature and humidity tester (Note 5) of 60 ° C. and 95% for 200 hours, there was no change in the appearance, the adhesion was 100/100, and the surface resistance was 2.3 × 10 ¹² Ω. In the ash adhesion test, no ash adhered.

Comparative Examples 1 and 2 A cured film was formed on an extruded acrylic resin plate in the same manner as in Example 1 using a photocurable resin composition comprising the components shown in Tables 1 and 2. The adhesion, hardness,
The antistatic property and the moisture resistance were evaluated. The results are shown in Tables 3 and 4 together with Example 1.

Examples 2 to 9 A cured film was formed on an extruded acrylic resin plate in the same manner as in Example 1 using the photocurable resin compositions comprising the components shown in Tables 5 and 6. The adhesion, hardness,
The antistatic property and the moisture resistance were evaluated. Table 7 shows the results.
And Table 8 below.

(Note 1) Adhesion 11 cut lines of the cured film reaching the substrate at intervals of 1 mm are inserted into the cured film 11 times each in the vertical and horizontal directions to make 100 1 mm stitches.
Stick cellophane tape on it and peel off sharply. This cellophane tape operation is repeated three times at the same location, and is expressed by the number of stitches that have not been peeled off.

(Note 2) Steel wool hardness (hereinafter, SW)
Abrasion test using steel wool with a count of 0000 A: no damage even when rubbed hard B: slightly damaged when rubbed hard C: slightly damaged when rubbed lightly D: markedly scratched even when rubbed lightly Get on

(Note 3) Surface resistance value The sample was left for 24 hours in an atmosphere of 23 ° C. and a relative humidity of 50%, and then measured with a hyper-insulation meter (SM-8210 manufactured by Toa Denpa).

(Note 4) Ash adhesion test After rubbing the cured film for 20 times with a cotton cloth, the ash was brought close to 1 cm to fresh tobacco ash, and the state of ash adhesion was observed. A: No ash attached B: Ash slightly attached C: Ash significantly attached

(Note 5) Moisture resistance constant temperature and humidity tester (TABAI ESPEC PLATI)
NOUS RAINBOW PR-2G) used, 60
The appearance and adhesiveness of the sample after standing at 200 ° C. × 95% humidity for 200 hours were observed. Further, an ash adhesion test was performed.

The abbreviations used in Table 1, Table 2, Table 5, and Table 6 indicate the following compounds, respectively. CEA: carboxyethyl acrylate HFPA: 2-hydroxy-3-phenoxypropyl acrylate TPTA: trimethylolpropane triacrylate HCFK: 1-hydroxycyclohexyl phenyl ketone HELI: 1-hydroxyethyl-2-lauryl imidazoline AELI: 1-aminoethyl-2 -Lauryl imidazoline

[0037]

[Table 1]

[0038]

[Table 2]

[0039]

[Table 3]

[0040]

[Table 4]

[0041]

[Table 5]

[0042]

[Table 6]

[0043]

[Table 7]

[0044]

[Table 8]

[0045]

The photocurable resin composition of the present invention comprises an imidazoline surfactant in combination with at least one salt selected from the group consisting of alkali metal salts, alkaline earth metal salts and ammonium salts as an antistatic agent. Therefore, even if the compounding amount of this antistatic agent is small, it is applied to the synthetic resin molded product,
After drying, when cured by irradiation with ultraviolet rays or the like, a film having excellent appearance and adhesiveness as well as particularly excellent antistatic performance can be formed.

────────────────────────────────────────────────── (5) References JP-A-62-282975 (JP, A) US Patent 4,382,102 (US, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08F 2 / 46-2/56 C08F 299/00-299/08 C08J 7/04

Claims (4)

(57) [Claims] 1. A photocurable resin composition containing an antistatic agent, wherein at least one salt selected from the group consisting of an alkali metal, an alkaline earth metal salt and an ammonium salt as an antistatic agent and an imidazoline surfactant. A photocurable resin composition, characterized by using in combination. 2. A photocurable resin composition comprising a (meth) acrylate oligomer having a carboxyl group and at least two acryloyloxy groups in one molecule and / or a carboxyl group and at least one acryloyloxy group in one molecule. The photocurable resin composition according to claim 1, further comprising a (meth) acrylate monomer having a group. 3. A synthetic resin molded article having a cured film formed by applying and curing the photocurable resin composition according to claim 1 on the surface of the synthetic resin molded article. 4. A synthetic resin molded article having a cured film formed by applying and curing the photocurable resin composition according to claim 2 on the surface of the synthetic resin molded article.