Abstract: The present invention provides methods and compositions for the reduction of the corrosion rate of already corroding steel reinforcements embedded in a hardened concrete structure as well as for the protective corrosion inhibition of uncorroded steel reinforcements embedded in a hardened concrete structure exposed to aggressive environments.
The inventive new compositions employed for the novel method are essentially based on one or more amino- and/or hydroxyalkylamino compound(s), which are partially or completely neutralized with one or more inorganic acid(s) and/or derivatives thereof and/or aliphatic carboxylic- and/or aromatic carboxylic acid(s), one or more surfactant(s) and one or more water-based or water-thinnable water repellent agent(s) selected from the group of organosilicones.
Type:
Grant
Filed:
May 11, 1999
Date of Patent:
June 11, 2002
Assignee:
Sika AG, Vorm, Kaspar Winkler & Co.
Inventors:
Beat Marazzani, Theodor A. Bürge, Urs Mäder
Abstract: An acidic aqueous phosphating solution is presented having 0.2 to 3 g/l of zinc ions, 3 to 50 g/l of phosphate ions expressed as PO4−3, and 0.05 to 4 g/l of an organic N-oxide containing a saturated, unsaturated or aromatic 5- or 6-membered ring system, where the N atom of the N-oxide is part of said ring system, and where the ratio by weight of phosphate ions to zinc ions is from 3.7 to 30:1. The solution is free of hydroxylamine and useful in phosphating metal surfaces.
Type:
Grant
Filed:
January 10, 2001
Date of Patent:
April 30, 2002
Assignee:
Henkel Kommanditgesellschaft auf Aktien
Inventors:
Bernd Mayer, Peter Kuhm, Pietro Balboni, Markus Senner, Horst-Dieter Speckmann, Juergen Geke, Jan-Willem Brouwer, Annette Willer
Abstract: A combination of sulfur-free azoles, preferably benzotriazole and tolyltriazole, with sulfur-containing azoles, preferably 2-mercaptobenzothiazole or mercaptobenzimidazole, prevents discoloration, staining, or corrosion of metal surfaces being coated with an organic protective coating from aqueous dispersion or solution.