JPH11279161A - Slightly volatilizing ultraviolet light absorber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new slightly volatilizable compound capable of retaining the solubility and dispersibility for polymers and mobility in the polymers and useful as an ultraviolet light absorber for coating films, films, sheets and plastic products exposed to wind and rain in the open air. SOLUTION: This compound is represented by formula I (R is a 1-8C alkyl; X is hydrogen or a halogen), e.g. a compound represented by formula II. The compound represented by formula I is obtained by reacting, e.g. (A) a 2-(2'- hydroxy-5'-alkylphenyl)benzotriazole with (B) N-methylolstearoylamide in the presence of (C) an acid or an alkali catalyst. For example, 2-(2'-hydroxy-5'- tertiary octylphenyl)benzotriazole or 2-(2'-hydroxy-5'-tertiary butylphenyl) benzotriazole is used as the component A. For example, p-toluenesulfonic acid or caustic soda is used as the component C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a non-volatile ultraviolet absorber for coating films, films, sheets and plastic products which are exposed to the weather outdoors.

[0002]

2. Description of the Related Art It is essential to add an ultraviolet absorber to plastic products, films, sheets and coatings used outdoors in order to prevent deterioration of a substrate due to ultraviolet rays. However, existing ultraviolet absorbers generally have a low molecular weight, and have high volatility not only at the stage of processing plastics but also at the stage of use, and have not yet achieved satisfactory effects. Therefore, attempts have been made to reduce the volatility by increasing the molecular weight by introducing a polyoxyalkylene group or cumyl group into the existing ultraviolet absorbers, but the compatibility with the polymer, the dispersibility, or There is a problem in mobility within the polymer, and it has not been satisfied.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide an ultraviolet absorbent which is compatible with a polymer, has good dispersibility, and has high mobility in a polymer, and is hardly volatile.

[0004]

Means for Solving the Problems The following compound obtained by reacting 2- (2'-hydroxy-5'-alkylphenyl) benzotriazole with N-methylol stearoylamide in the presence of an acid or an alkali catalyst. A 2- (2′-hydroxy-3′-stearoylaminomethyl-5′-alkylphenyl) benzotriazole-based compound represented by the general formula:

[0005]

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Here, R represents a C1 to C8 alkyl group, and X represents hydrogen or halogen.

Examples of the compounds belonging to these include, but are not limited to, the following chemical formulas (2), (3), (4) and (4).

[0008]

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[0009]

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[0010]

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[0011]

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[0012]

The compounds of the present invention are described below by way of examples. Example 1 Synthesis of Chemical Formula 2 2- (2′-hydroxy-5 ′) was placed in a 300 ml flask.
-Tertiary octylphenyl) benzotriazole (manufactured by Kyodo Yakuhin) 32.3 g (0.1 mol), N-methylol stearoylamide (manufactured by Nippon Kasei) 37.5 g (0.12)
Mol), toluene 100 g, P-toluenesulfonic acid 1
Add 1.9 g (0.01 mol) of water salt, and add 90 to 100 ° C.
After cooling for 10 hours at room temperature, the mixture was cooled to room temperature, insolubles were filtered off, the filtrate was concentrated under reduced pressure, the precipitated crystals were filtered, washed with methanol, and dried to obtain a compound having a melting point of 91 to 93 ° C. 0.7g
(Yield: 82% of theory) was obtained as a white powder.

Example 2 Synthesis of Chemical Formula 2 In Example 1, N-methylol stearoylamide was changed to 31.3 g (0.1 mol) and P-toluenesulfonic acid was changed to 1.5 g of a 10% aqueous solution of sodium hydroxide. After the reaction in the same manner as in Example 1, 30 g of a 0.5% hydrochloric acid aqueous solution was added, and the mixture was sufficiently stirred, allowed to stand and separated, the toluene layer was concentrated under reduced pressure, the precipitated crystals were filtered, washed with methanol, and dried. Thus, 54 g (yield: 87.4% of theory) having a melting point of 91 to 93 ° C. was obtained as a white powder.

Example 3 Synthesis of Chemical Formula 3 In Example 2, 2- (2'-hydroxy-5'-third
Grade octylphenyl) benzotriazole instead of 2
-(2'-hydroxy-5'-tert-butylphenyl)
26.7 g of benzotriazole (Cipro Kasei)
(1 mol) and operating in the same manner as in Example 2 to obtain 49.5 g (yield: 88% of theory) of [Chemical Formula 3] having a melting point of 85 to 87 ° C as a white powder.

Example 4 Synthesis of Chemical Formula 4 In place of 2- (2′-hydroxy-5′-tertiary octylphenyl) benzotriazole in Example 2,
Using 22.5 g (0.1 mol) of (2'-hydroxy-5'-methylphenyl) benzotriazole (manufactured by Kyodo Yakuhin), the same operation as in Example 2 was performed to obtain a melting point of 98 to 98%.
47.3 g (yield: 91.0 of theory) at 102 ° C.
%) As a white powder.

[0016]

According to the present invention, there is provided a coating film which is exposed to the weather outdoors.
It is intended to provide a non-volatile ultraviolet absorber for films, sheets, and plastic products.

Claims (1)

[Claims] 1. 2- (2 ′) represented by the following general formula,
-Hydroxy-3'-stearoylaminomethyl-5 '
-Alkylphenyl) -benzotriazole compounds. Embedded image Here, R represents a C1 to C8 alkyl group, and X represents hydrogen or halogen.