99% Optical Brightening Agents OBA CAS No 7128-64-5 ISO14001

This product is yellow-green powder. The melting point is 200～201℃, and the decomposition temperature is greater than 220℃. Hardly soluble in water, soluble in alkanes, fats, mineral oils, waxes and common organic solvents.  Solubility/(g/100 ml): methanol 0.05; acetone 0.5; toluene 5.3; carbon tetrachloride 5.9; tetrahydrofuran 5.5; DMF 0.8; chlorobenzene 10.2; cyclohexane 3.3; xylene 5.5; dioctyl phthalate Ester 0.7; Water 0.01. The maximum absorption wavelength is 374nm.

Mainly used for whitening PVC, PS, PE, PP, ABS and other plastics and acetate, paints, coatings, inks, etc.

Mainly used for the whitening of synthetic fibers and plastic products. It has a significant effect of increasing the beauty of colored plastic products. It is also used for PE, PP, PVC, PS, ABS, etc.

Put 120 kg of chlorobenzene into the reactor, and add 21 kg of o-amino-p-tert-butylphenol. Under stirring, 19 kg of chloromethyl imine ether hydrochloride were slowly added dropwise at room temperature. After dripping, the temperature is raised to reflux. The reaction time is 3 to 4 hours. Recycle chloroform. Approximately 24 kg of brown oil was obtained. Add 200 kg of water to the vulcanizing kettle, then add 45 kg of sodium disulfide and 0.5 kg of PTC (as a phase transfer catalyst). After stirring to dissolve, it was cooled to 10°C, and the dichloromethane solution of the above reactants was added dropwise, stirred for 10 hours, left to stand for separation, and the organic layer was washed with water. The dichloromethane was recovered, and about 23 kg of yellow solid was obtained. Dissolve it in 100 kg of dimethyl sulfoxide and add 2.8 kg of glyoxal. Under the protection of nitrogen, it was stirred and cooled to 0°C, and 20 kg of 30% sodium methoxide methanol solution was added dropwise. The reaction time is 5-6h. Use 1:2 dilute hydrochloric acid to acidify the material to a pH of 5-6, evaporate the methanol under reduced pressure, cool and filter, wash the filter cake with water until it is neutral, and dry. Recrystallize with ethyl acetate to obtain the optical brightener OB.