| 摘要 |
525,670. Synthetic resin articles. WACKER GES. FUR ELEKTROCHEMISCHE INDUSTRIE GES., A. Feb. 25, 1939, No. 6279. Convention date, Feb. 26, 1938. Addition to 499,686. [Class 2 (iii)] The manufacture of driving-belts or ropes or other frictional driving means according to the parent Specification is modified by the addition of, to the material from which the belt is made, or by the after-treatment of, an acid substance. Acid substances, which include bodies such as phosphoric acid, sulphuric acid, hydrobromic acid, lactic acid, sulphuric acids, sulphonates and trichloracetic acid, are defined as those which exhibit an acid reaction to ketones. |
