| 摘要 |
558,292. Synthetic resin composition. LORD, W. E., and WILKINSON, G. H. June 25, 1942, No. 8699. [Class 2 (iii)] [Also in Group XXXVI] Carbon-zinc elements for use in dry cells of the superposed-layer type are made by applying to a zinc plate a composition comprising carbon black, coarse particles of graphite, and a binder preferably containing an artificial resin of the phenol-aldehyde type which is soluble in and reacts with a drying-oil. In order to avoid reducing the size of the graphite particles, the composition is mixed as distinct from ground, so as to obtain a rough surface after the binder has hardened. The mixture may be applied to the zinc plate with a scraper having a serrated edge so as to corrugate the exposed surface. The varnish may comprise " Epok " (Registered Trade Mark) resin R.18, raw tung oil, linseed stand oil, litharge, manganese linoleate, and white spirit, or the resin known in the trade as " XRB 254 " may be used. Alternatively the varnish known as " G.C. 129 " may be used. The complete mixture may comprise 240 parts by weight of varnish, 103 parts of graphite, and 33 parts of carbon black. |
