| 摘要 |
449,026. Coated fabrics. IMPERIAL CHEMICAL INDUSTRIES, Ltd., Millbank, London. Dec. 18, 1934, No. 36313. Convention date, Dec. 19, 1933. [Class 140] Containers, envelopes, wrappers, &c. are made from paper coated firstly with an adhesive composition containing uncured rubber, and secondly with a powdered material such as starch or soapstone adapted to prevent adhesion of the rubber composition to a similar surface under slight pressure, but allowing adhesion under greater pressure. Suitable rubber compositions are (1) Pale crepe rubber, barytes and agerite white, (2) Pale crÛpe rubber, barytes, whiting, zinc oxide, montan wax, stearic acid and rubber oil, and these are preferably applied to the paper by a calendering operation, while the starch may be applied in a usual type of starching box, excess being removed by brushing. The containers are made by placing together blanks, and applying sufficient pressure to fracture the starch covering, to the regions where adhesion is required. This seal can be readily broken and resealed, or it may be made permanent by a vulcanizing treatment. |
