Z-Cote was acquired from SunSmart in 1999 by BASF. It has been used in sunscreen formulations since at least 1993 in microfine form. The initial 1991 Z-Cote patent placed emphasis on broad-spectrum protection, especially UVA. Only in 1993 did the FDA approve an alternative petrochemical sunscreen ingredient, avobenzone, that also provided protection against UVA.