| 摘要 |
928,257. Polyolefin coated sheeting. KALLE A.G. March 26, 1962 [March 28, 1961], No. 11504/62. Class 140. A polyolefin coated sheeting is produced by extruding a polyolefin upon a sheeting surface to which an oxidizing agent for the polyolefin has been previously applied. The sheeting, e.g. foils of regenerated cellulose, aluminium or paper, may also have an anchoring agent, e.g. melamine - formaldehyde resin, polyalkylene 'mine, alkyl titanates, and bivalent or multivalent diisocyanates, applied thereto. The anchoring agent and the oxidizing agent may be applied as a mixture or separately, the order being immaterial. The oxidizing agent, e.g. chromic acid, chromates, chlorates, persulphates, perborates, nitrates, nitrites, sodium peroxide, hydrogen peroxide and organic peroxides such as cumyl hydroperoxide, cyclohexanone peroxide, methyl ethyl ketone peroxide and benzoyl peroxide, may be applied in aqueous or organic solution or dispersion, the coated sheeting being dried prior to passage through a pair of squeeze rollers where it is combined in known manner with the extruded polyolefin film. The polyolefin e.g. polymers and copolymers of ethylene or propylene, may contact the sheeting surface at a distance of less than 5 cm. from the orifice of the slot die through which it is extruded. The surface may be partially covered with other layers, e.g. an image in printing ink, prior to coating with polyolefin. The surface not provided with the polyolefin layer may be coated with, for example, a moistureproofing lacquer. |
