Perforation
“A perforation is a small hole in a thin material or web. There is usually more than one perforation in an organized fashion, where all of the holes are called a perforation. The process of creating perforations is called perforating, which involves puncturing the workpiece with a tool.” (Wikipedia, Perforation, 1/4/2010)
Recent US Patents
10/5/2010
7,807,066
Method of Manufacturing a Porous Resin Substrate having Perforations and Method of Making a Porous Resin Substrate including Perforations having Electrically Conductive Wall Faces
Higher frequencies and higher speeds in electronics require materials with lower dielectric constants. Porous resin materials have lower dielectric constants than nonporous resin. Thus foams are logical candidates for low dielectric materials. In some applications the material is perforated and filled with a conductive material to conduct electrons through the material. Perforating foams usually results in a solid surface with damaged and conductive material. Uenoyama et al have developed a method of manufacturing a perforated porous resin substrate with a constant low dielectric constant by perforating a porous fluoropolymer material and etching the perforation with a sodium/naphthalene etchant solution. This results in a degenerated surface which is removed by hydrogen peroxide oxidation. The result is a clean, porous surface which can hold a catalyst for electroless plating and forming a conductive surface through the material.