Patent GB-1049588-A (GB)
Title: A graphite material and process for producing same
IPC: D04H1/04
Filed: 1964-04-10
Abstract: A flexible graphite web, produced by compressing graphite which has previously been expanded in a preferred direction (see Division C1), may be coated with metals, e.g. Al, Ag, Au or Cu, carbides or oxides by known techniques.ALSO:A flexible graphite web material, characterized by having a density of at least 5 pounds per cubic foot, a thickness of from 0.1 mil. to 500 mils., and a tensile strength of from 250 to 3200 pounds per square inch at room temperature, is produced by compressing expanded graphite particles having a "C" direction (the direction perpendicular to the graphite layers) dimension of at least 80, and preferably at least 200, times that of the particles prior to expansion.  The expanded particles may be compressed to give a web material having a density of up to 137 pounds per cubic foot.  The unexpanded particles, which may be pyrolytic, natural or Kish graphite particles, preferably have a size of from 0.043 to 25 mm. and are expanded by wetting with an oxidizing agent at a temperature of up to 125 DEG  C., rinsing the wetted particles with an aqueous solution, and impregnating the particles with an expanding agent.  Preferably, the aqueous rinsing solution forms the expanding agent and the particles are rapidly heated to a temperature higher than the vaporization temperature of the solution. The expanded particles, which may be mixed with particles of an organic resin, or a metal powder, or clay, or with metal filaments or glass fibres before being compressed, may be continuously deposited on a moving surface to form a continuous length of deposited particles which are subjected to a first compression step to form a self-supporting web which is further compressed and sized.  The web may be heated after sizing and subjected to a further sizing step. The surface of the web may be embossed, or provided with a metal or adhesive coating; such adhesive may contain filaments of metal, glass or flexible graphite. Laminates may be formed by adhering the adhesive-coated web to a second flexible graphite web or to another material, for example paper, cloth fabric or polymeric material.  The web may be cut or slit into strips which may be woven or braided, and such strips or the uncut web may be rolled or wound into solid or hollow structures.ALSO:A flexible graphite web material, produced by compressing graphite which has previously been expanded in a preferred direction (see Division C1), may be coated on at least one surface with a reflective metal coating or an adhesive, for example a pressure sensitive adhesive coating.  The adhesive may contain filaments of metal, glass or flexible graphite.  The adhesive coated web may be slit into strips to provide a flexible adhesive thermal insulating tape or a flexible adhesive tape for use in forming shapes, for example tubular articles.  The web material may be combined with a carrier sheet, for example paper, having an ahesive layer which transfers to the web material on removal of the paper from the web.  The web material in strip or tape form may be formed into shapes which are then coated with adhesive to provide self-supporting rigid structures.ALSO:A flexible graphite web (see Division C1), is cut or slit into strips which may be woven, braided or otherwise formed into a fabric.  A warp or weft of graphite may be woven with a weft or warp of cotton or wire.  A braid may be formed from strands of graphite and strands of other material.  Strips of graphite may be twisted or wound helically to form threads, which may be plied together, and may be used in weaving or braiding.