NEAR-FIELD NOISE SUPPRESSION FILM

摘要

A noise suppression film having reduced unevenness of electromagnetic wave noise absorbability, which comprises a thin Ni film, which is vapor-deposited on one surface of a stretched plastic film of polyethylene terephthalate, and then subject to a heat-shrinkage-causable heat treatment at a temperature in a range of 110-170° C. for 10 minutes to 1 hour, (a) the light transmittance of the thin Ni film measured with laser rays having a wavelength of 660 nm being 3-50%, and (b) the surface resistance of the thin Ni film being 10-200 Ω/square when measured on its square test piece TP of 10 cm×10 cm under a load of 3.85 kg applied via a flat pressure plate, with a pair of electrodes each having a length completely covering a side of the test piece disposed on opposing side portions of the test piece.

主权项

1. A method for producing a noise suppression film having reduced unevenness of electromagnetic wave noise absorbability, which comprises the steps of
vapor-depositing a thin Ni film on one surface of a stretched plastic film of polyethylene terephthalate; and heat-treating said thin Ni film on said stretched plastic film at a temperature in a range of 110-170° C. for 10 minutes to 1 hour to cause such a heat shrinkage of said stretched plastic film that (a) a light transmittance of said thin Ni film measured with laser rays having a wavelength of 660 nm is 3-50%, and that (b) the surface resistance of said thin Ni film is 10-200 Ω/square when measured as a square test piece TP of 10 cm×10 cm under a load of 3.85 kg applied via a flat pressure plate, with a pair of electrodes each having a length completely covering a side of said test piece disposed on opposing side portions of said test piece.