JP2975511B2 - Weather resistant resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an weatherable resin composition characterized by the use of (II) oxide cerium sol, JP
A weatherable resin composition whose weather resistance has been improved by including a fixed amount of ceric oxide sol or ceric oxide derived from the sol and a benzotriazole-based ultraviolet absorber in a resin such as a plastic, a paint, or a sealant. It provides things.

[0002]

2. Description of the Related Art As a method of absorbing ultraviolet rays of resin compositions such as plastics, fibers, paints, etc., there has been known a method of using various organic ultraviolet absorbers. Has improved weather resistance. However, when such organic UV absorbers are used for resins such as plastics and films, they are subjected to heat treatment during processing of the resins. Cannot show its performance. In addition, the UV absorber on the treated resin surface is easily eluted by water or an organic solvent, volatilized by long-term use, or has insufficient stability to air oxidation, and has many problems to be improved. Leaving a point. Accordingly, inorganic UV absorbers that are less likely to deteriorate in place of such organic UV absorbers have recently attracted attention.

[0003]

SUMMARY OF THE INVENTION The present inventors have focused on inorganic UV absorbers in place of organic UV absorbers based on such actual conditions, and developed a sol composed of ceric oxide ( Japanese Unexamined Patent Publication No. 1-148710) and a method for absorbing ultraviolet light of various materials using this sol have been proposed. (JP-A-1-30643
However, as a result of further study, it was found that various resin compositions using this sol had insufficient weather resistance. That is, only the ultraviolet absorption band of the ceric oxide sol does not provide sufficient weather resistance to the resin, and the appearance of an ultraviolet absorber having a wider absorption band is desired.

[0004]

Accordingly, as a result of further study on a method for improving the weather resistance of the resin by using the ceric oxide sol in combination with another ultraviolet absorber, the ceric oxide sol and the organic sol were mixed. When used in combination with a benzotriazole-based UV absorber that is a UV-based absorber,
They have been found to act synergistically and exhibit a remarkable effect on improving the weather resistance of the resin, and have completed the present invention based on such findings. That is, the present invention relates to 100 parts by weight of a resin.
(II) oxide cerium sol or ceric oxide 0.1 to 20 parts by weight <br/> benzotriazole-based UV absorber 0.1 to 20 weight derived from the sol as CeO ₂ with respect to
The present invention relates to a weather-resistant resin composition comprising:

[0005]

The following is a more detailed description of the weatherable resin composition of the present invention. The ceric oxide sol used in the present invention,
It can be obtained by the method described in Japanese Patent Application Laid-Open No. Hei 1-148710 or Japanese Patent Application Laid-Open No. Hei 5-123111, which is an invention filed by the present inventors earlier. That is, a cerium oxide sol can be obtained by reacting a cerium chloride with a hydroxide of an alkali metal or ammonia to form a gel, and then subjecting the gel to a hydrothermal treatment. Also, ceric oxide sol can be obtained by reacting cerous carbonate with an oxidizing agent such as hydrogen peroxide to produce ceric oxide gel and then peptizing the gel with an acid. However, such a ceric oxide sol is not limited to those obtained by these production methods.

The ceric oxide sols obtained by these methods all use water as a dispersion medium, but resin compositions are generally produced using an organic solvent in many cases. May be converted into an organic solvent dispersed sol by an appropriate means. That is, as the means, a generally known method of hydrophobizing an aqueous sol may be used. For example, for example, a surfactant is adsorbed on the surface of such an aqueous sol, and the resulting mixture is treated with an organic solvent. Then, the sol particles are transferred to the organic solvent layer by contact with the sol, and the sol transferred to the organic solvent layer after the transfer may be collected. In addition, such a sol can be dried by a suitable drying means and powdered for use.

Further, the organic solvent used in such a case differs depending on the type of the weather-resistant resin composition of the present invention, the purpose of use, the type of the surfactant used, and the like, and the type is not particularly limited. Such as methanol, ethanol, propanol, butanol, octanol, toluene, xylene, benzene, cyclohexane, cyclohexanone, petroleum ether, chloroform, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate, dioctyl phthalate and dioctyl adipate Examples thereof include a plasticizer, carbon tetrachloride, and a high-boiling-point solvent (for example, Hyalom, manufactured by Nippon Oil Co., Ltd.).

Next, as organic UV absorbers generally used, various UV absorbers of benzophenone type, salicylate type, cyanoacrylate type, nickel complex type and benzotriazole type are known. However, among these organic UV absorbers, the only UV absorber having the effect of the present invention is a benzotriazole UV absorber. Therefore, the use of organic ultraviolet absorbers other than benzotriazoles has little effect on improving the weather resistance of the resin, although the reason is not clear.

The type of the benzotriazole-based UV absorber used in the present invention includes 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-3,
5-di-n-butylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3'-t-butyl-5'-methylphenyl
-5-chlorobenzotriazole, 2- (2'-hydroxy-5'-t
-Octylphenyl) benzotriazole, 2- (2′-hydroxy-3,5-di-t-amylphenyl) benzotriazole, 2
-(2'-hydroxy-3,5-di-t-butylphenyl) benzotriazole, 2- (2'-hydroxy-3,5-bisphenyl) benzotriazole, hydroxyphenylbenzotriazole derivative, 2- (2 ' -Hydroxyphenyl) benzotriazole oligomers.

[0010] The types of resins that can be used as the weatherable resin composition of the present invention include vinyl chloride resin, chlorinated vinyl chloride resin, polyethylene resin, chlorinated polyethylene resin, chlorinated polypropylene resin, polypropylene resin, polyester resin, and the like. Polystyrene resin, acrylonitrile / styrene resin, vinylidene chloride resin, vinyl acetate resin, polyamide resin, polyacrylate resin, polyimide resin, polycarbonate resin, butadiene resin, polyacetal resin, ionomer resin, ethylene / vinyl chloride copolymer resin, ethylene / vinegar Bi-copolymer resin, ethylene vinegar
PVC graft polymer resin, polyphenylene resin, polysulfone resin, methacrylic resin, acrylic / fluorine resin, acrylic / silicone oligomer, silicone resin, epoxy-containing silicone / acrylic resin, vinyl ester resin, furan resin, phenol resin, melamine resin, guanamine resin, Examples include urea resin, polyurethane resin, aromatic polyester resin, diacryl phthalate resin, ketone resin, epoxy resin, xylene resin, maleic resin, phenoxy resin, coumarone resin, polyvinyl formal resin, polyvinyl butyral resin, and the like.

Next, the ceric oxide sol to be contained in the weatherable resin composition of the present invention or the use ratio of ceric oxide derived from the sol to the benzotriazole-based ultraviolet absorber will be described in detail. First, the amount of the ceric oxide sol or the ceric oxide derived from the sol varies depending on the type of the resin in the weatherable resin composition, the use, and the like, and also depends on the absorption wavelength band for performing the intended ultraviolet shielding. not be said different indiscriminately, but generally about 0.1 to 20 parts by weight of CeO ₂ with respect to 100 parts by weight of the resin of the weather resistant resin composition. The cerium oxide derived from the sol according to the present invention refers to a cerium oxide sol in the form of a dried powder or in a sol state, resulting in cerium oxide particles. And so on.

The amount of the benzotriazole-based UV absorber used is generally about 0.1 to 20 parts by weight based on 100 parts by weight of the resin in the weatherable resin composition. In this case, if the amount of the benzotriazole-based ultraviolet absorber is less than 0.1 part by weight, a remarkable synergistic effect with ceric oxide in improving weather resistance cannot be expected, and conversely, 20 parts by weight Even if it is used more than above, it is not economical because the effect corresponding to the used amount cannot be obtained, and it is not preferable because the disadvantageous characteristics of the organic ultraviolet absorber as described above are remarkably exhibited.

[0013] The weatherable resin composition of the present invention may further comprise a plasticizer, a PVC stabilizer, a light stabilizer, an antioxidant, an antioxidant, a leveling agent, as an additive to the resin, in addition to the use of such a benzotriazole-based ultraviolet absorber. An agent, an antistatic agent, a flame retardant, a colorant, a lubricant and the like can be used in combination depending on the use.

[0014]

The present invention will be further described below with reference to examples of the present invention, but the present invention is not limited to these examples. Also,
All percentages are by weight unless otherwise specified.

(Example 1) 50 kg of ceric ammonium nitrate aqueous solution (CeO ₂ 2.0%) and sodium hydroxide aqueous solution (Na
33.8 kg of (1.5%) were simultaneously added to a reaction vessel to which 10 kg of water had been previously added, with stirring using separate metering pumps for about 1 hour. The temperature of the reaction solution at this time was 21 ° C.

After the reaction, the formed gel is filtered, washed with water, and treated with Ce.
O ₂ 17.33%, NO ₃ 0.3%, Na and NH ₃ each yielded a wet cake of 20 ppm or less. To 2000 g of this wet cake, 121 pieces of water
4 g and 252 g of hydrochloric acid (HCl 35%) were added to obtain a uniform slurry solution, which was subjected to a heat treatment at 90 ° C. for 3 hours. After the heat treatment, the conductivity of the solution was cloudy at 120 mS / cm (25 ° C.).
By adjusting the temperature to / cm (25 ° C.) or less, the solution became a transparent sol solution. This sol solution is passed through an ultrafiltration device (SLP manufactured by Asahi Kasei Corporation).
-1053), followed by washing and concentration to obtain ceric oxide sol (CeO ₂ 20%).

100 g of this ceric oxide sol (CeO ₂ 20%)
Was diluted to 1000 g with water, and 48 g of condensed sodium phosphate (10% aqueous solution) and dodecylbenzyldimethylammonium chloride as a cationic surfactant (manufactured by NOF Corporation, Cation F2, 20.5 g of an active ingredient (50%) was added and the mixture was reacted to obtain a precipitate. The precipitate is filtered,
After washing, it was dried at 100 ° C. This dried product is C
eO _{2 was} 60.5%, P was 3.1%, and dodecylbenzyldimethylammonium (surfactant) was 21.1%. This dried product was dispersed in toluene to obtain an organic solvent-dispersed (organo-type) ceric oxide sol (CeO ₂ 20%).

Using this organo-type ceric oxide sol, raw materials were prepared in the proportions shown in Table 1 to obtain a coating composition. This coating composition was overcoated on a red acrylic enamel (undercoat), and this was coated with a super UV tester (W-13 type, manufactured by Dainippon Plastics Co., Ltd.) to obtain a black panel temperature of 60.
An accelerated weathering test was performed under a cycle condition of irradiation at 24 ° C for 24 hours and spraying for 24 hours. The color difference value of the overcoated coating composition,
It was measured at each time using a color difference meter (Z-1001DP type, manufactured by Nippon Denshoku Industries Co., Ltd.), and the weather resistance of the coating composition was evaluated by comparison with the color difference value immediately after application. Table 1 shows the measurement results of color difference values for each composition.

[0019]

[Table 1] Note) * 1 Lumiflon LF-200 (resin solid content: 60%) manufactured by Asahi Glass Co., Ltd. * 2 2- (2'-human peroxy-5'-methylphenyl) pentasotrisol * 3 Asahi Denka Kogyo Co., Ltd.

Example 2 A coating composition was obtained by using the dried organoceric oxide sol (CeO ₂ 60.5%) obtained in Example 1 and mixing the raw materials in the proportions shown in Table 2. . Using a sunshine weather meter (sunshine car horn arc type, Ska Tester Co., Ltd.WEL-SUN-DC type)
Based on the accelerated weathering test method of JIS K5400 (General Test Method for Paints), an accelerated weathering test was performed under a cycle of irradiation for 2 hours and spraying for 18 minutes. Immediately after the preparation of the coating composition and at each time, the gloss retention (at 60 ° C. specular gloss) and the color difference value were measured to evaluate the weather resistance of the coating composition. Table 2 shows the color difference values and gloss retention measurement results for each composition.

[0021]

[Table 2] Note) * 1 Nippon Polyurethane Co., Ltd., Nipporan-179 * 2 2- (2'-Heatoxy-5'-methylphenyl) benzotriazole * 3 Nippon Polyurethane Co., Ltd., C-HX

Example 3 A dried product of ceric oxide sol (CeO ₂ 60.5%) obtained in Example 1 was dispersed in methyl isobutyl ketone to obtain a ceric oxide dispersion of CeO ₂ 20%. This dispersion was blended at the ratio shown in Table 3 and blended with a Henschel mixer at 1100 rpm for 6 minutes, and then pelletized with a single screw extruder having a die temperature of 250 ° C. and a screw rotation of 25 rpm. Using this, injection molding was performed at a temperature of 250 ° C. to obtain a sheet-shaped resin composition having a thickness of 2 mm.

This sheet-shaped resin composition was irradiated with a super UV tester (W-13 type, manufactured by Dainippon Plastics Co., Ltd.) at a black panel temperature of 60 ° C. under irradiation conditions of 24 hours irradiation and 24 hours spraying. A weather resistance acceleration test was performed. The coloring state of the sheet immediately after the preparation of the sheet-shaped resin composition and by the weather resistance test were compared by measuring the Hunter type yellowness. The Hunter-type yellowness is calculated from the color coordinate values L, a, and b based on the tristimulus value X,
Y and Z were calculated, and the yellowness was calculated by the following formula according to JIS K-7103 (Testing method for yellowness and yellowing degree of plastic). Yellowness (YI) = 100 (1.28X−1.06Z) / Y The Hunter-type yellowness is represented by a difference from a value immediately after preparation of the sheet-shaped resin composition. For comparison, a similar test was conducted using a composition containing no organic UV absorber. Table 3 shows the results.

[0024]

[Table 3] Note) * 1 A phenolic antioxidant manufactured by Asahi Denka Kogyo Co., Ltd.
O-80) * 2 2- (2'-Hydroxy-3'-t-butyl-5'-methylphenyl) -5-chlorobenzotriazole * 3 Hintamine light stabilizer (Adekastaf L) manufactured by Asahi Denka Kogyo Co., Ltd.
A-52)

[0025]

The weatherable resin composition of the present invention is characterized by containing ceric oxide sol or ceric oxide derived from ceric oxide sol and a benzotriazole-based ultraviolet absorber. Thereby, the organic ultraviolet absorber and the inorganic ultraviolet absorber ceric oxide exhibit excellent synergistic properties in improving the weather resistance.

Accordingly, examples of application of the weather-resistant resin composition of the present invention are as follows: UV cut lamps such as fluorescent lamps, UV-absorbing glass for various uses, provision of weather resistance for light-transmitting plastics, coloring for foods, etc. Replacement of bottles, UV absorption of cosmetic bottles, UV absorption of cosmetics, improvement of weather resistance of various paints and functional coatings, weather resistance of UV curable paints and coatings, transparent adhesive To improve the weather resistance of various films and transparent rubbers, to impart weather resistance to functional powders, to impart weather resistance to fibers, to improve the weather resistance of fluorescent pigments, to prevent ultraviolet rays, and to cut plastic films.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) C08K 3/22 C08K 5/3492 C08L 1/00-101/14

Claims (1)

(57) [Claims] (1) CeO ₂ is used for 100 parts by weight of resin.
Second cerium sol or weather resistant resin composition comprising a ceric 0.1-20 parts by weight of oxide derived from the sol and benzotriazole ultraviolet absorber 0.1 to 20 parts by weight oxide Te.