Light Yellow Crystal 99% Fluorescent Brightener PF FB135 CAS No.1041-00-5

This product is a milky white paste with good dispersibility and is neutral. It is a non-ionic compound. The melting point is 182～184 ℃. Insoluble in water, soluble in DMF and ethanol, acid resistance to pH=2～3, alkali resistance to pH=10. Hard water resistance to 5×10 -4 . The best dyeing temperature is 150 ℃ (in a neutral or weak alkaline bath), and it can withstand 180-200 ℃ roasting. Its slurry and diluent are not sensitive to light.

First, drive 33 parts of xylene into the reaction kettle, then add 3.5 parts of o-amino-p-cresol, 2.0 parts of hydroxysuccinic acid, and 0.1 part of boric acid. Add carbon dioxide and heat to boiling under stirring.  Reflux for 12 h, and separate the generated water with a water trap during the reaction. After the reaction is completed, the temperature is lowered to 130°C, activated carbon is added, stirred and heated to reflux for half an hour, filtered, the filtrate is cooled to 15°C, crystals are precipitated, and dried to obtain a crude product.

Put the crude product, water and polyvinyl alcohol into a sand mill and grind to a certain degree of fineness, then add an appropriate amount of leveling agent O, formaldehyde, polyvinyl alcohol solution, etc., and fully stir to obtain the finished product (the amount of material used in the preparation is the mass fraction) .