| abstract |
It is an object of the present invention to provide a fiber-treatment capable of providing improved flame retardancy towards synthetic fiber comprising polyester.This invention provides a flame retardant for polyester-based synthetic fiber, comprising a polyester having a weight-average molecular weight of about 500 to about 20, 000,said polyester being obtained from (A) an aromatic dicarboxylic acid component having no anionic group other than the carboxylic groups, (B) a diol and (C) a phosphinic acid derivative represented by the formula: wherein R1 and R2 are independently selected from the group consisting of hydrogen atom and hydrocarbyl groups containing 1-22 carbon atoms, or R1 and R2 are joined into a divalent group to form a ring together with the phosphorus and oxygen atoms; n is 0, 1 or 2; and Z is a monovalent succinic residue represented by wherein R3 is a hydrogen atom or an alkyl group containing 1-4 carbon atoms;the molar ratio of the components (A)/(B)/(C) being 1/0.8-9/0.2-5. |