Patent ID: 8366980

Claim:
A method for producing a fluorinated hollow structural body, said method comprising the steps of: providing a non-hollow structural body made of a hydrocarbon polymer, wherein said non-hollow structural body is formed from an outer surface and a center portion, wherein said hydrocarbon polymer forms said outer surface and said center portion, and wherein said hydrocarbon polymer optionally has a nitrogen-containing group, a silicon-containing group, an oxygen-containing group, a phosphorus-containing group, or a sulfur-containing group; said non-hollow structural body into contact with a treating gas containing fluorine under a predetermined processing condition to allow the treating gas to permeate the structural body from the outer surface toward the center portion and to fluorinate the structural body except for the center portion thereof; exposing the unfluorinated center portion after said fluorination treatment; and removing the exposed, unfluorinated center portion by dissolving or by the application of heat, thereby forming the fluorinated hollow structural body, wherein in order to remove the unfluorinated center portion, the method includes one of the following steps: masking a portion of the exposed outer surface of the non-hollow structural body before said fluorination treatment in order to prevent fluorination at the masked portion due to said fluorination treatment, and subsequently removing said masking after said fluorination treatment, or cutting to expose the unfluorinated center portion after said fluorination treatment.