The author measured infrared absorption spectra of four natural products similar to Japanese urushi (Rhus vernicifiua) after three years of complete hardening; Tsuta-urushi, Yama-urushi (Rhus trichocarpa), Nurude (Rhus javanica) and Kaki-shibu (persimmon tannin). The results were compared with those of Japanese and Formosan urushi. Yama-urushi is generally similar to Japanese urushi, but differs in that it has absorption bands at 1,510, 1,150 and 820 cm_-1 Tsuta-urushi is fairly similar to Formosan urushi, Nurude is partly similar to Japanese urushi and Tsuta-urushi, but different in that it has no absorption at 1,280 cm_-1. Lakishibu is different from the urushi family in that it has no absorption at 1280 cm _-1 and almost no absorption at 2,925 and 2,850 cm_1-1. See also AATA 13-647.