The mine or cargo lapis

摘要

1402732 Epoxy resin composition TEIJIN Ltd 10 Nov 1972 [13 Nov 1971] 52068/72 Headings C3B and C3P [Also in Division B6] A composition, useful as a pencil lead, comprises a finely divided colouring agent dispersed in an uncured solid epoxy resin, prepared from bisphenol A and epichlorohydrin, which has M.W. 700-7000. The colouring agent may be graphite or an organic pigment used in conjunction with a white filler to impart rigidity to the composition. Up to 50% by wt. of the epoxy resin may be replaced by another thermoplastic resin, e.g. an acrylonitrile styrene polymer or ethyl cellulose. A metal soap may be present to modify the hardness of the composition.