TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation: No preparation method is given.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The polymer substance is acrylic acid-based polymers, polyester-based polymers and/or polycarbonate-based polymers. The polymer substance has a glass transition point (Tg) of -80 degrees C or higher and 200 degrees C or lower. The polymer substance is polyethylene terephthalate, a polyacrylate ester or a polycarbonate. The polymer material is prepared by: melt-kneading of the polyethylene terephthalate and (I) at 200 degrees C or higher; and dissolving the polyacrylate ester or the polycarbonate and (I) in a solvent having a boiling point of 200 degrees C or lower to give a solution, and applying the solution on a base substrate. Preferred Composition: (I) is contained in an amount of 0.1-50 mass.% with respect to 100 mass.% of the polyethylene terephthalate, polyacrylate ester or polycarbonate. Preferred Definitions:    X1, X2 = S.    SPECIFIC COMPOUNDS - The use of 61 compounds (A) is disclosed e.g. 2-ethyl-hexanoic acid 2-(3-tert-butyl-5-oxo-isoxazol-4-ylidene)-7-(2-ethyl-hexanoyloxy)-benzo(1,3)dithiol-4-yl ester of formula (A1), 2-ethyl-hexanoic acid 2-(3-tert-butyl-5-oxo-isoxazol-(4Z)-ylidene)-6-chloro-7-(2-ethyl-hexanoyloxy)-benzo(1,3)dithiol-4-yl ester, 2-ethyl-hexanoic acid 6-tert-butyl-2-(3-tert-butyl-5-oxo-isoxazol-(4Z)-ylidene)-7-(2-ethyl-hexanoyloxy)-benzo(1,3)dithiol-4-yl ester, 2-ethyl-hexanoic acid 2-(3-tert-butyl-5-oxo-isoxazol-(4Z)-ylidene)-7-(2-ethyl-hexanoyloxy)-6-methyl-benzo(1,3)dithiol-4-yl ester and dipropyl-carbamic acid-(3-tert-butyl-5-oxo-isoxazol-4-ylidene)-7-dipropylcarbamoyloxy-benzo(1,3)dithiol-4-yl ester.    EXAMPLE - Dipropyl-carbamic acid 2-(3-tert-butyl-5-oxo-isoxazol-4-ylidene)-7-dipropylcarbamoyloxy-benzo(1,3)dithiol-4-yl ester was added to polyethylene terephthalate (5 g) in the preparation of film (50 mu m) to be an absorbance of 1 at the absorption maximum wavelength, and the mixture was melt-kneaded at 265 degrees C and cooled to give a bulk of ultraviolet absorbent-containing polyethylene terephthalate. The ultraviolet absorbent-containing polyethylene terephthalate was stretched at 280 degrees C to give an ultraviolet absorbent-containing polymer film.