We are a strong manufacturer for optical brightening agent (oba), also called fluorescent brightener, optical brightener, fluorescent brightening agent (fba), fluorescent whitening agent (fwa) and so on. (1) optical brightening agent used in paper: Ba (c. I.113), vbl(c. I.85), hst (c. I.357), bc (c. I.204), hpe, bbu (c. I.220) (2)optical brightening agent used in cotton & synthetic fiber: 4bk, dst, mst, wh-a, hxt, ba (c. I.113) (3)optical brightening agent used in polyester fabric: Er-330(c. I.199), eb-330 (c. I.199:1), dt (c. I.135) (4) optical brightening agent used in polyester fiber and plastics: Er(c. I.199), er-ii(c. I.199:1), er-iii, pf(c. I.135), ob(c. I.184), ob-1(c. I.393), ob-2, ob-4, fp-127/cbs-127(c. I.378), kcb(c. I.367), ksn, mdac (c. I.91 or c. I.140) (5) optical brightening agent ued in detergent: Cxt(c. I.71), cbs-x(c. I.351), dms,31# (6) intermediates of optical brightening agent Sulfanilic acid, 4,4'-bis(diethoxyphophonomethyl)dipheny Thiophene-2,5-dicarboxyl acid 4,4'-bis(chloromethyl)-diphenyl Pls feel free to contact if there is need.