| 摘要 |
651,912. Resin-containing board. OLDHAM & SON, Ltd., and BOOTH, F. June 8, 1948, No. 15398. [Class 96] Microporous material, for storage battery separators is made by reducing to a fine pulp in the presence of a wetting agent shredded wood, e.g. balsa, quipo or obiche, digested with 4 per cent caustic soda solution, filtering the resultant aqueous suspension and forming a sheet therefrom, impregnating the sheet with a water-soluble resin capable of being polymerized to form an acid-resisting polymer, e.g. phenolformaldehyde resin, heating to polymerize the resin therein, dipping it in a wetting agent and finally drying. The impregnated sheet may be dried prior to the heating. The weight of wetting agent, e.g. a rubber phenolic resin, added to the pulp may be 0.5 to 5.0 per cent, and the wetting agent into which the sheet is dipped may be a 1 to 5 per cent solution of sulphonated turkey red oil. The sheet may be grooved or given any desired form by cutting but preferably by moulding it during the heating. Specification 645,354 is referred to. |
