Patent ID: 7087781

Claim:
A scale inhibitor comprising at least one polymethylenephosphate derivative having the following formula: wherein n is an integer comprised between 2 and 15000, wherein M is a hydrogen or a cation, wherein R 1 , R 2 , and R 3 are each independently selected from the group consisting of, CH 2 PO 3 M 2 , CH 2 R 4 , wherein R 4 is CHOHCH 3 , CHOHCH 2 Cl, or CHOHCH 2 OH, (CH 2 ) m SO 3 M, wherein m is 3 or 4, and CH 2 CH 2 R 5 , wherein R 5 is CONH 2 , CHO, COOR 6 , COOX, or CN, wherein R 6 is CH 3 or C 2 H 5 , and wherein X is an alkali metal or ammonium, and wherein at least one of R 1 , R 2 , and R 3 is not CH 2 PO 3 M 2 .