Acidic cleaner for metal surfaces
AssigneeEcolab USA Inc.
InventorThomas Tyborski
Life of this patent
Estimating the term…
Abstract
The invention relates to a acidic composition for cleaning surfaces of metal or alloys which are susceptible to corrosion comprising i) an ester of phosphoric acid, diphosphoric acid or polyphosphoric acid, ii) a benzotriazole derivative of the general formula (I) in which each of the groups R1, R2, R3, R4 and R5 is the same or different and is hydrogen atom, an alkyl group, an alkenyl group, or an acyl group, iii) a phosphonic acid of the general formula R6—PO—(OH)2 (II) in which the group R6 is alkyl group, alkenyl group, aryl group, or arylalkyl group and iv) an acidic source. The invention further relates to a use solution and to a method for cleaning.
Claims17
An acidic composition for cleaning surfaces of metal or alloys comprising:
- i) an ester of phosphoric acid, diphosphoric acid or polyphosphoric acid,
- ii) a benzotriazole derivative of the general formula:
- in which each of the groups R1, R2, R3, R4 and R5 is the same or different and is a hydrogen atom, an alkyl group, an alkenyl group, or an acyl group;
- iii) a phosphonic acid of the general formula R6—PO—(OH)2 in which the group R6 is alkyl group, alkenyl group, aryl group, or arylalkyl group;
- and
- iv) an acidic source,
- wherein the composition does not contain metal organic substances and the composition has a pH lower than 3.
A method of cleaning a metal surface comprising:
- (a) applying to the surface, a composition comprising:
- i) an ester of phosphoric acid, diphosphoric acid or polyphosphoric acid,
- ii) a benzotriazole derivative of the general formula:
- in which each of the groups R1, R2, R3, R4 and R5 is the same or different and is a hydrogen atom, an alkyl group, an alkenyl group, or an acyl group;
- iii) a phosphonic acid of the general formula R6—PO —(OH)2 in which the group R6 is alkyl group, alkenyl group, aryl group, or arylalkyl group;
- and
- iv) an acidic source;
- (b) cleaning the surface;
- and
- (c) removing the composition from the surface by rinsing or drying,
- wherein the composition does not contain metal organic substances and the composition has a pH lower than 3.
Dependencies are inferred from the claim text.