Method for preparation of edged medical tool
AssigneeShin-Etsu Chemical Co., Ltd.
InventorsHajime Kitamura, Tamaki Iida
Life of this patent
Estimating the term…
Abstract
An edged medical tool, such as scalpels and injection needles, is imparted with unexpectedly improved incisiveness by first providing a carbonaceous coating layer of 1 to 20 nm thickness having a crystalline structure of diamond by a method of plasma-induced vapor-phase deposition in an atmosphere of a mixture of hydrogen gas and a hydrocarbon gas at a microwave frequency of 1 to 10 GHz and then etching the thus formed diamond-like coating layer in a plasma of hydrogen gas to such an extent that the thus etched surface has a roughness of 0.5 to 5 nm.
Claims4
A method for the preparation of an edged medical tool which comprises the steps of:
- (a) exposing a base body of the edged medical tool, maintained at a temperature from 500.degree. to 1300.degree. C., to an atmosphere of a plasma generated in a gaseous mixture composed of hydrogen gas and a hydrocarbon gas by applying a high-frequency electric power at a frequency in the range from 1 GHz to 10 GHz to deposit a carbonaceous coating layer having an at least partially crystalline structure of diamond and a thickness in the range from 1 nm to 20 nm on the surface of the base body of the edged medical tool in a plasma-induced vapor-phase deposition process;
- and
- (b) exposing the coated base body of the edged medical tool to an atmosphere of a plasma generated in hydrogen gas by applying a high-frequency electric power at a frequency of 1 MHz or higher to effect etching of the surface of the at least partially crystalline carbonaceous coating layer to such an extent that the surface has a surface roughness in the range from 0.5 nm to 5 nm.
Dependencies are inferred from the claim text.