PREPARATION OF FLAKE OF TEREPHTHALOYL DICHLORIDE AND/OR ISOPHTHALOYL DICHLORIDE

摘要

PURPOSE:To prepare colorless, high-quality flakes of the titled compound useful as a raw material of fibers, etc., economically in an industrial scale, by using a flaker drum, etc., wherein the part contacting with the liquid is made of a metal such as nickel, niobium, etc. or a specific stainless steel. CONSTITUTION:Flaking of terephthaloyl dichloride (abbreviated as TPC) and/or isophthaloyl dichloride is carried out by using a flaker drum or a steel belt wherein the part contacting with the liquid is made of a metal selected from Ni, Nb, Ta and Pt or a stainless steel having an Ni-content of =10%. The stainless steel is, e.g. SUS316, SUS316L, NAS175T, etc. The flaking is preferably carried out by heating the molten liquid of TPC, etc. at a temperature higher than the melting point by about 30 deg.C (preferably 10-20 deg.C). The temperature of the cooling surface is preferably lower than the melting point by =3 deg.C.