Static shielding film
AssigneeMinnesota Mining and Manufacturing Company
InventorMaynard E. Skrivseth
Life of this patent
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Abstract
Flexible sheet materials and envelopes are described which are useful for packaging electronic components. The sheet material includes an electrically insulating film with a conductive layer on the upper surface and an antistatic layer carried by the lower surface. The antistatic layer includes a fluoroaliphatic sulfonamide polyether compound. Optionally a tie layer may be included between the film and the antistatic layer.
Claims26
A flexible sheet material being adapted for packaging an electronic component and being sufficiently transparent to enable visual identification of said component through said sheet material, said sheet material comprising:
- (a) self-supporting electrically insulating film;
- said film having upper and lower major surfaces;
- (b) an electrically conductive layer carried by said upper surface of said film;
- (c) an antistatic layer carried by said lower surface of said film, said antistatic layer comprising a polymer having dispersed therein a fluoroaliphaticsulfonamide polyether compound with imparts to said antistatic layer a surface resistivity in the range of 10.sup.7 to 10.sup.14 ohms per square;
- wherein said antistatic layer further comprises a lithium perfluorosulfonate salt;
- and
- (d) a tie layer secured to said lower surface of said film;
- wherein said antistatic layer is secured to said tie layer.
An envelope adapted to receive and protect an electronic component, said envelope having walls formed of a flexible material having first and second major surfaces, said first surface defining an outer surface of the envelope and said second surface defining an inner surface of the envelope, wherein said material comprises:
- (a) a self-supporting electrically insulating film having a volume resistivity of at least about 10.sup.10 ohm-centimeters;
- said film having upper and lower major surfaces;
- (b) an electrically conductive layer carried by said upper surface of said film;
- said conductive layer providing a surface resistivity no greater than 10.sup.4 ohms per square;
- (c) an antistatic layer carried by said lower surface of said film, said antistatic layer comprising a polymer having dispersed therein a fluoroaliphaticsulfonamide polyether compound, wherein said antistatic layer provides a surface resistivity in the range of 10.sup.7 to 10.sup.14 ohms per square;
- wherein said antistatic layer further comprises a lithium perfluorosulfonate salt;
- (d) a tie layer secured to said lower surface of said film;
- wherein said antistatic layer is secured to said tie layer.
Dependencies are inferred from the claim text.