Patent ID: 8871973

Claim:
A polyalkylene glycol producing catalyst which is composed of a salt of a phosphazenium cation and an active hydrogen compound anion, represented by the following formula (2): [in the above formula (2), each of R 1 and R 2 which are independent of each other, is a C 1-10 alkyl group, an unsubstituted or substituted C 6-10 phenyl group, or an unsubstituted or substituted C 6-10 phenylalkyl group, provided that R 1 and R 2 , or R 2 's, may be bonded to each other to form a ring structure, n is a real number of from 2 to 8, and Y n− is an anion of an active hydrogen compound which is obtained by removing n protons from an active hydrogen compound Y].