Electrically conductive foam and method of preparation and use
AssigneeCharleswater Products, Inc.
InventorGeorge R. Berbeco
Life of this patent
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Abstract
A static-free, polymeric surface mat to prevent the accumulation of static charge, particularly in the packaging and handling of electronic components and devices, which mat comprises a nonconductive, synthetic-material layer with a top surface, optionally an adhesive layer on the bottom surface of the synthetic material, and a solid or foam layer of a conductive material, such as an open-cell urethane foam impregnated with finely-divided conductive particles, and a film-forming binder material to secure the particles uniformly onto the foam.
Claims13
A static-dissipating, synthetic, surface-covering sheet material which comprises:
- (a) an electrically nonconducting, synthetic sheet laminate material having a hard thermoset resin top surface suitable for use as a surface covering;
- and
- (b) an electrically conductive layer of a polymeric, film-forming, particulate binder material secured to the bottom surface of the synthetic sheet material, the polymeric material containing uniformly dispersed therein a static-reducing amount of electrically conductive particulate material wherein the particulate material comprises from about 2 to 40% by weight of the polymeric binder material, whereby static charges, accumulating on the top surface of the synthetic sheet material, are dissipated through the electrically conductive layer.
A static-dissipating, synthetic, surface-covering sheet material which comprises:
- (a) a flat, electrically nonconducting, synthetic sheet material having a washable top surface suitable for use as a surface covering;
- (b) an adhesive layer securing the bottom surface of the synthetic sheet material to the electrically conductive layer;
- and
- (c) a thin, electrically conductive layer of a polymeric, film-forming, particulate binder material, the conductive layer comprising an open-cell, polymeric urethane foam material, the polymeric foam layer uniformly impregnated with the electrically conductive particles, the binder material secured to the bottom surface of the synthetic sheet material by the adhesive layer, the polymeric material securing the conductive particles to the polymeric foam and containing uniformly dispersed therein a static-reducing amount of electrically conductive particulate material having a particle size of less than about 40 millimicrons and a nitrogen surface area of 100 to 1200 m.sup.2 /gram, the surface resistance of the electrically conductive layer characterized by a surface resistance of less than 5,000 ohms per square inch, whereby static charges, accumulating on the top surface of the synthetic sheet material, are dissipated through the electrically conductive layer.
A static-dissipating, synthetic, surface-covering sheet material which comprises:
- (a) an electrically nonconducting, synthetic, sheet laminate material having a hard, smooth, thermoset-resin top surface and a top surface suitable for use as a surface covering;
- (b) an adhesive layer securing the bottom surface of the synthetic sheet meterial to the electrically conductive layer;
- and
- (c) a thin, electrically conductive, solid coating layer of a polymeric, film-forming, particulate binder material comprising a styrene-butadiene polymer, the polymeric binder material secured to the bottom surface of the synthetic sheet material by the adhesive layer, the polymeric material containing uniformly dispersed therein a static-reducing amount of electrically conductive particulate material comprising carbon-black particles having a particle size of less than about 40 millimicrons and a nitrogen surface area of 100 to 1200 m.sup.2 /gram, whereby static charges, accumulating on the top surface of the synthetic sheet material, are dissipated through the electrically conductive layer.
Dependencies are inferred from the claim text.