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:
May. 30, 1995
Filed:
Jan. 26, 1994
David B Montgomery, Cary, NC (US);
Erwin A Vogler, Newhill, NC (US);
Becton Dickinson and Company, Franklin Lakes, NJ (US);
Abstract
In a method to modify the chemistry of a portion of the surface of an article, the surface is placed adjacent an electrode in a plasma chamber, the distance to the wall of the chamber being at least five times the size of the electrode. A plasma of very high power density is generated in a discharge volume surrounding the electrode so that the surface area closest to the electrode receives a very intense plasma which diminishes with increasing distance from the discharge volume thus forming a chemical gradient on the article surface. The preferred article is a tube having one closed end, and the gradient may be formed from either the closed end or the open end. The gradient may be of decreasing glass-like character or decreasing plastic-like character.