| 摘要 |
460,658. Treating wood. KOEHLER MANUFACTURING CO. June 26,1935, Nos. 18283 and 18284. Convention dates, June 26, 1934 and June 14, 1935. Drawings to Specification. [Class 140] [Also in Group XXXVI] Electric battery separators are made of a wood such as balsa which when treated with an alkaline solution acquires the properties of a semi-permeable membrane. The treatment of a balsa wood separator consists first in boiling it in water for some hours to get rid of acetic acid, sap and other organic constituents of the wood. A small quantity of an alkaline substance such as soda ash is added to the water. The treatment with boiling water and alkali is repeated and the separators are then boiled in dilute sulphuric acid and finally washed. Before being placed in the battery the separators are soaked in dilute sulphuric acid. |
