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:
Apr. 30, 1991
Filed:
Oct. 18, 1989
Horst Schafer, Aschaffenburg-Obernau, DE;
Gerhard Ludwig, Stromberg, DE;
Rainer Sunderdiek, Aschaffenburg-Schweinheim, DE;
Ciba-Geigy Corporation, Ardsley, NY (US);
Abstract
A method for disinfecting a contact lens comprises immersing the lens in an aqueous solution of H.sub.2 O.sub.2 having a pH of 4 or below and adding to the solution a neutralizing agent comprising a catalyst for decomposing any residual H.sub.2 O.sub.2 and a retarding agent for delaying the decomposition of the H.sub.2 O.sub.2 for a predetermined time in order to permit sterilization of the lens to be substantially complete. The retarding agent preferably comprises either a polymeric coating which dissolves gradually in the H.sub.2 O.sub.2 solution or a semipermeable membrane enveloping the catalyst. The neutralizing agent preferably also contains an auxiliary material which raises the pH of the acidic H.sub.2 O.sub.2 solution. The enzymatic decomposing agent can be embedded in a particulate carrier substance forming the bottom part of a two part container, the upper part of which contains an aqueous solution of H.sub.2 O.sub.2, and the bottom part being separable from the upper part and covered by an inert sieve netting impermeable to the H.sub.2 O.sub.2 solution but permeable to the decomposing agent.