| 摘要 |
<p>1,011,795. Laminates. PETROLITE CORPORATION. Aug. 22, 1962 [Aug. 23, 1961], No. 32266/62. Drawings to Specification. Heading B5N. A laminated sheet material suitable for the manufacture of cartons comprises at least two coherent plies of sheet material adhesively united by a moisture-proof thermoplastic adhesive, the ratio of the thickness of the adhesive to the thickness of the thickest coherent sheet exceeding 8 to 10. The coherent plies may both be paper or one may be metal foil, e.g. aluminium, and have a thickness in the range 0À002 to 0À012 inch. The adhesive may be (a) a micro-crystalline wax to which has been added wetting agents, hydrous adsorbents and viscosity builders, e.g. butyl rubber, polyisobutylene, polyethylene, copolymers of vinyl acetate and ethylene or colloidal silica so that its viscosity at the temperature of application is in excess of 75 centipoises, (b) low molecular weight polymers, e.g. polystyrene, polyethylene, polyterpenes, isoprene polymers, chlorinated natural and synthetic rubbers or natural rubbers, (c) cellulose derivatives, the thickness of the adhesive lying in the range 0À003 to 0À015 inch. Specifications 1,011,792, 1,011,796, 1,011,798, 1,011,799 and 1, 011, 800 are referred to.</p> |
