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:
Feb. 18, 2003
Filed:
Aug. 28, 2000
Wayne W. Frenier, Katy, TX (US);
HydroChem Industrial Services, Inc., Deer Park, TX (US);
Abstract
The present invention is directed to methods for preparing quaternary ammonium salts, particularly pyridinium and quinolinium salts. By preparing these salts in a solvent selected from the group consisting of propylene glycols, propylene glycol ethers and mixtures thereof, the production of undesirable by-products and contamination of the product with undesirable solvents are minimized, if not eliminated. Using the preparation methods of the present invention low hazard corrosion inhibitors and aqueous cleaning solutions using these inhibitors may be prepared. In fact, by preparing dodecyl pyridinium bromide in dipropylene glycol methyl ether as the solvent, a particularly desirable corrosion inhibitor characterized by a low toxicity and a high flash point has been prepared. The present invention thus provides the safer corrosion inhibitors and cleaning solutions long sought by industrial cleaning services.