Patent ID: 6605421
Filing Date: 2003-08-12
Classification: C01B,G03C

Abstract:
An aqueous solution comprising a hydroxylamine salt in an amount of 18 to 35 weight-%, wherein the aqueous solution further comprises at least one compound selected from the group consisting of amino polycarboxylic acids and compounds represented by the following Formulas [1] to [6] in an amount of 1 to 30 weight-%, and pH of the aqueous solution is within the range of from 2 to 6: wherein R1 through R7 each represent independently a hydrogen atom, â€”OH, â€”COOM, â€”PO3M2, â€”SO3M or a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, in which M is a hydrogen atom or an alkali metal; n and m each represent 0 or 1, provided that both m and n are not 0 at the same time; wherein at least one of A through F represents a sulfonic acid group or a sulfonic acid ester group, and the others represent a hydrogen atom, a halogen atom, a hydroxyl group or a saturated or unsaturated alkyl group; wherein, at least one of G through N represents a sulfonic acid group or a sulfonic acid ester group, and the others represent a hydrogen atom, a halogen atom, a hydroxyl group or a saturated or unsaturated alkyl group;R41â€”SO3Mâ€ƒâ€ƒFormula [4]wherein R41 represents a substituted or unsubstituted, saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms, and M represents a hydrogen atom, or an alkali metal;HOâ€”(A1â€”O)l1â€”(A2â€”O)l2â€”(A3â€”O)l3â€”Hâ€ƒâ€ƒFormula [5]wherein A1, A2, and A3 each represent a substituted or unsubstituted, straight or branched chain alkylene group, which may be the same or different; l1, l2, and l3 each represent 0 or an integer of 1 to 500; wherein R1 represents a substituted or unsubstituted hydroxyalkyl group or a substituted or unsubstituted aminoalkyl group; and R2 and R3 each represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted hydroxyalkyl group or a substituted or unsubstituted benzyl group, provided that R1 and R2, R2 and R3, R3 and R1, or R1, R2 and R3 may combine with each other to form a ring.