The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 04, 1994
Filed:
Oct. 02, 1992
Applicant:
Inventors:
Klaus Wittel, Franfkurt am Main, DE;
Georg Blumlhuber, Oberasbach, DE;
Assignee:
Metallgesellschaft Aktiengesellschaft, Frankfurt am Main, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C23G / ;
U.S. Cl.
CPC ...
134-2 ; 134 10 ; 252540 ;
Abstract
In a process of cleaning metal surfaces with aqueous alkaline cleaning solutions, which contain silicates and surfactants and are recycled after ultrafiltration, a solution is employed which contains silicate only as a sodium silicate and/or potassium silicate of the formula Na.sub.2 O.2SiO.sub.2.xH.sub.2 O and/or K.sub.2 O.2SiO.sub.2.xH.sub.2 O. The cleaning solution is preferably adjusted to a pH value between 7 and 12 and to a concentration (expressed as SiO.sub.2) of 0.1 to 20, particularly 0.5 to 10 g, silicate per liter.