How do I find patents?
You can use Ei Patents which offers sophisticated search and retrieval tools across all patents registered with the U.S. and European Patent Offices.
Another good search tool is esp@cenet Patents search.
esp@cenet provides abstracts, bibliographic data and full text of patents for: EPO, France, Germany, Switzerland, United Kingdom, United States and WIPO. Abstracts and bibliographic data are provided for: China and Japan. Bibliographic data is provided for: Argentina, ARIPO, Australia, Austria, Belgium, Brazil, Bulgaria, Canada, Croatia, Cuba, Cyprus, Czechoslovakia, Czech Republic, Denmark, Egypt, Ellas, Eurasian Patent Office, Finland, GDR, Hong Kong, India, Ireland, Israel, Italy, Kenya, Korea, Latvia, Lithuania, Luxembourg, Malawi, Mexico, Moldova, Monaco, Mongolia, The Netherlands, New Zealand, Norway, OAPI, Philippines, Poland, Portugal, Romania, Russia, Slovakia, Slovenia, South Africa, Soviet Union, Spain, Turkey, Vietnam, Yugoslavia, Zambia, Zimbabwe.
Also see: Overview of Patents & Patent Searching