Patent · US Expired

Electromagnetic shielding sheet and method of producing the same

US6733869B2 · kind B2 · utility

7Cited by
6References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 21, 2003
Grant dateMay 11, 2004
Priority date
Expiry dateFeb 21, 2023

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31678
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A metallic foil and a transparent substrate film are laminated with an adhesive layer. The roughness of the adhesive-layer-side surface (lower surface) of the metallic foil is such that the maximum height Rmax is more than 0 and less than 4 &mgr;m. As long as the maximum height Rmax falls in the range, the adhesive layer never contains air bubbles in such sizes that reflectance is adversely affected. The roughness of the surface (upper surface) of the metallic foil, opposite the adhesive-layer-side surface, is preferably such that the arithmetic mean roughness Ra is between 0.02 &mgr;m and 1 &mgr;m. As long as the arithmetic mean roughness Ra is in this range, it is possible to efficiently conduct vacuuming to bring, into close contact, a photosensitive resin layer and a photomask in sheet form placed on the photosensitive resin layer, before effecting the pattern-wise exposure of the photosensitive resin layer.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.