HEAT- AND FIRE-RESISTANT SHEET AND ITS MANUFACTURING PROCESS (OPTIONS) Russian patent published in 1997 - IPC

FIELD: protection of equipment incorporating electronic sources against electrostatic discharge and/or electromagnetic effects. SUBSTANCE: heat- and fire-resistant conducting shield has electricity conducting layer composed of paper pulp wherein conducting fibers are combined with aromatic polymer and covered on one or two sides with insulating layer composed of paper pulp containing polymethaphenyleneisophthalamide flakes and fibrids; mentioned conducting layer is composed of paper pulp containing polymethaphenyleneisophthalamide fibrids and conducting fibers and flakes of polymethaphenyleneisophthalamide . One of manufacturing processes involves the following operations: wet sheet composed of paper pulp is covered on one or two sides with wet sheet made of paper pulp containing polymethaphenyleneisophthalamide flakes and fibrids. Laminated structure obtained is subjected to paper-making process, heat and pressure treatment at temperature not lower than polymethaphenileneisophthalamide flake glass transition point. Optional method includes the following operations: paper sheet produced by paper-making process from wet sheet composed of polymethaphenyleneisophthalamide fibrids and flakes, and conducting fibers is covered on one or both sides with paper sheet produced by paper-making proceed from paper pulp containing fibrids and flakes of polymethaphenyleneisophthalamide and laminated structure obtained is treated with heat and pressure at temperature not lower than glass transfer point of polymethaphenyleneisophthalamide flakes. EFFECT: improved quality of sheet obtained by these methods. 5 cl, 8 dwg, 6 tbl