| 摘要 |
PURPOSE:To provide a baglike container having good high pressure steam sterilization resistance and heat-sealability and withstanding low temp. use of about -200 deg.C by using a laminate wherein an inner layer is composed of ultrahigh MW non-stretched polyethylene according to a low pressure polymerization method and an outer layer is composed of a heat-resistant and extremely low temp.-resistant biaxially stretched high density polyethylene. CONSTITUTION:The ultrahigh MW non-stretched polyethylene of an inner layer has an MW of 1000000 or more according to a viscosity method and 3000000 or more according to a light scattering method. An outer layer 2 is composed of biaxially stretched high density polyethylene having a thickness of 0.012-0.075mm, transparency of 2.5-3.8%, tensile breaking strength of 15-18kg/mm<2>, tensile breaking elongation of 60-85% and punching impact strength of 7.5kg.cm. An adhesive 3 is applied to the corona discharge treatment surface of the outer layer 2 and the corona discharge treatment surface of the inner layer is laminated to the outer surface to form a laminate and the inner layers of two laminates are heat-sealed in a mutual contact state to form a baglike container. By this method, extremely low temp. resistance is obtained from the composition of the inner surface and fusion at the time of high pressure steam sterilization is not generated and fusion sealing can be performed at temp. higher than normal temp. Heat resistance and low temp. resistance are provided from the composition of the outer layer and there is no difference in a seal part at the time of the preparation of the container and the generation of a crack at low temp. is prevented. |
