| 摘要 |
<p>PURPOSE:To obtain a laminated film of an inexpensive packaging material superior in whole physical strength, by a method wherein the innermost layer of a bias monoaxial molecular oriented multi-layer coextrusion inflation film is stuck by quasi- adhesion without making use of an adhesive layer and molecular oriented axes are crossed. CONSTITUTION:Coextrusion of a film is performed by turning one side out of inside and outside mandrels faster than the other side end an inner layer is laminated directly, in a multi-layer coextrusion film whose innermost and outermost layers are comprised respectively of an ethylene copolymer resin film whose softening point is lower than that of the outermost layer and a molecular oriented high-density polyethylene resin film layer containing at least 50% high-density polyethylene resin whose density is at least 0.940g/cm<3> and MI is 0.1-5.0g/10 minutes. The ethylene copolymer resin film layer which is apt to perform blocking and the high-density polyethylene resin film layer which is apt to perform molecular orientation are used respectively as the innermost and outermost layers. A bias-monoaxial-molecular-oriented film is obtained by turning one side out of the inside and outside mandrels more fast. Molecular oriented axes can be crossed by only laminating the film by folding up in a state of a flat plate during a continuing molding process.</p> |
