Patent US4102857 - Pyrazole derivatives - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More ??Sign inAdvanced Patent SearchPatentsNew ultraviolet light-absorbing compounds of the formula ##STR1## IN WHICH R1 is a substituent, e.g. alkyl, R2 is a substituent, e.g. alkyl, R3 is hydrogen or a substituent, e.g. alkyl, N is 1, 2 or 3, and R is an n-valent, optionally substituted benze