Phosphate-free cleaner for metallic surfaces with reduced pickling erosion
AssigneeChemetall GmbH
InventorsAndre Schaus, Dominic Weil
Life of this patent
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Abstract
Described herein is a water-based, alkaline cleaner concentrate for producing a cleaner for metallic surfaces, the concentrate including a) at least one (meth)acrylic acid homopolymer having a weight-average molar mass in the range from 3 000 to 19 000 g/mol and b) at least one (meth)acrylic acid copolymer having a weight-average molar mass in the range from 50 000 to 100 000 g/mol. Also described herein are a corresponding cleaner for metallic surfaces with reduced pickling erosion, a process for anticorrosive treatment of metallic surfaces that includes a corresponding cleaning step, a metallic surface obtained by the process, and a method of use thereof in the sector of the metalworking industries.
Claims20
A water-based, alkaline cleaner concentrate for producing a cleaner for metallic surfaces, which comprises
- a) at least one (meth)acrylic acid homopolymer having a weight-average molar mass in the range from 3 000 to 19 000 g/mol and
- b) at least one (meth)acrylic acid copolymer having a weight-average molar mass in the range from 50 000 to 100 000 g/mol,
- wherein the at least one (meth)acrylic acid copolymer comprises at least one linear copolymer of (meth)acrylic acid and at least one monomer containing a vinyl group and at least two acid groups selected from the group consisting of carboxylic acid groups and sulfonic acid groups.
A water-based, alkaline cleaner for metallic surfaces, which comprises
- a) at least one (meth)acrylic acid homopolymer having a weight-average molar mass in the range from 3 000 to 19 000 g/mol,
- b) at least one (meth)acrylic acid copolymer having a weight-average molar mass in the range from 50 000 to 100 000 g/mol, and
- c) optionally at least one nonionic surfactant,
- wherein the at least one (meth)acrylic acid copolymer comprises at least one copolymer of (meth)acrylic acid and at least one monomer containing a vinyl group and at least two acid groups selected from the group consisting of carboxylic acid groups and sulfonic acid groups, and wherein, if the cleaner is a fresh cleaner, component a) is present in a concentration of at most 0.65 g/l, calculated as polyacrylic acid and component b) is present in a concentration of at most 0.35 g/l, calculated as poly(acrylic acid-alt-maleic acid).
Dependencies are inferred from the claim text.