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EP0240147A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Transparent sheet material for electrostatic copiers

Assignee: 3M Co
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Filing: 1987-02-26
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Granted: —
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Expires: 2007-02-26
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Abstract

Abstract This invention relates to transparent sheet material suitable for making transparencies in plain paper electrostatic copiers. When transparent, polymeric sheets are imaged in a conventional electrostatic copying machine, static charge on the surfaces of the sheets causes them to jam the machine or to pass through the machine without having an image formed thereon. Jamming can be caused by multiple feedings of sheets, i.e. more than one sheet entering the imaging zone of the copier at the same time. Multiple feeding can result from two or more sheets clinging together on account of static charge or excessively high coefficient of friction. While excessively high coefficient of friction can be reduced by proper selection and/or treatment of the surface material of the transparency sheet, it is desired to provide treatment to the transparent sheet material to reduce static charge, thus resulting in fewer jams and fewer unimaged sheets. This invention provides transparent sheet material for use in plain paper electrostatic copiers comprising (a) a flexible, transparent, heat resistant, polymeric film base, (b) an imaging receiving layer carried upon a first major surface of the film base, and (c) a layer of electrically conductive prime coat interposed between the image receiving layer and the film base. This sheet material can be used in either powder-toned or liquid-toned plain paper copiers for making transparencies.

Inventors

  • 👤 Bruce W. C/O Minnesota Mining And Wittnebel

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-10-28 20:06
CPC Classifications
G; G03; G03G; G03G7/00; G03G7/006; G03G7/0006; G03G7/002; G03G7/0026; G03G7/004; G03G7/0046; G03G7/0053; G03G7/0073; G03G7/008; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31507; Y10T428/31721; Y10T428/31786; Y10T428/31797; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/3192

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 48 words
Transparent sheet material comprising: (a) a flexible, transparent, heat resistant, polymeric film sheet base, (b) a layer of electrically conductive prime coat coated upon at least one major surface of said film sheet base, (c) an image receiving layer coated upon the surface of said prime coat layer.
Claim 2
Dependent Claim 48 words
Transparent sheet material comprising: (a) a flexible, transparent, heat resistant, polymeric film sheet base, (b) a layer of electrically conductive prime coat coated upon at least one major surface of said film sheet base, (c) an image receiving layer coated upon the surface of said prime coat layer.
Claim 3
Dependent Claim 22 words
The sheet material of claim 1 wherein the surface resistivity of the film sheet base is at least 1 × 10¹³ ohms/sq.
Claim 4
Dependent Claim 27 words
The sheet material of claim 1 wherein the surface resistivity of the prime coat layer is from about 1.7 × 10¹⁰ to about 7 × 10¹² ohms/sq.
Claim 5
Dependent Claim 27 words
The sheet material of claim 1 wherein the surface resistivity of the image receiving layer is from about 1.7 × 10¹⁰ to about 7 × 10¹² ohms/sq.
Claim 6
Dependent Claim 19 words
The sheet material of claim 3 wherein the layer comprises a polymeric material and an electrical conductivity-imparting organic salt.
Claim 7
Dependent Claim 21 words
The sheet material of claim 5 wherein the salt is selected from the group consisting of nitrates, sulfates, and ammonium salts.
Claim 8
Dependent Claim 33 words
The sheet material of claim 5 wherein said polymeric material is selected from the group consisting of gelatin, polyesters, homopolymers and copolymers of vinylidene chloride, and copolymers of vinyl acetate and vinyl chloride.
Claim 9
Dependent Claim 27 words
The sheet material of claim 5 wherein the layer comprises a copolymer derived from vinylidene chloride monomeric units and methyl acrylate monomeric units, and stearamidopropyl-dimethyl-beta-hydroxyethyl ammonium nitrate.
Claim 10
Dependent Claim 29 words
The sheet material of claim 1 wherein the film sheet base is made of a material selected from the group consisting of polyesters, polyimides, polycarbonates, polysulfones, and cellulose triacetate.
Claim 11
Dependent Claim 20 words
The sheet material of claim 1 wherein said image receiving layer comprises a polymeric material and an electrical conductivity-imparting material.
Claim 12
Dependent Claim 49 words
The sheet material of claim 10 wherein said polymeric material is selected from the group consisting of polymethylmethacrylates, polyesters, cellulosics, polyvinyl acetates, polyvinyl chlorides, copolymers of vinyl chloride and vinyl acetate, vinylnitrile-butadiene-styrene terpolymers, polyvinylidene chlorides, polyurethanes, polymethacrylates, copolymers of polystyrene or derivatives of polystyrene and pyridine or pyridines derivatives.
Claim 13
Dependent Claim 18 words
The sheet material of claim 1 further incuding a protective coating layer coated over the image receiving layer.

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