1.fluorescent optical Brightener for Cotton 4BK (c.i. 113)2.be used as brightener of contton, linen, silk, polyamide fiber ... C /min, keep the temperature at 50-100°C for 20-40min, then lower to 50-30°C --> wash ... setting (120°C -150°C )×1-2 minUse:Mainly be used as brightener of contton, linen, silk, polyamide fiber ,wool ... requirement of the user.fluorescent optical Brightener for Cotton 4BK (c.i. 113)