| 摘要 |
<p>PURPOSE:To obtain a sheet container whose heat resistance is high, by a method wherein a sheet material made of polyethylene and terephthalate resin is made into a primary intermediate-molded article through vacuum molding and the like, secondary orientation molding of which is performed by orienting the same into a product container after the same has been made into a secondary intermediate-molded article by making the primary intermediate-molded article heat and deform heat-shrinkably. CONSTITUTION:A sheet material 1 has been heated up to the temperature close to the crystallization temperature and lower than the crystallization temperature, and as for a molding primary mold 2, it is set up at a mold temperature through which orientation and molding can be performed under a state wherein the sheet material is not become crystallizable thermally at the time of secondary molding. Then although a primary intermediate-molded article 3 is molded into a secondary intermediate-molded article 5 by a cored mold 4 through heat shrinkage, maintenance of a shape after heating and bestowing of a shape of the secondary intermediate-molded article 5 are performed by the cored mold 4. Hereupon, residual stress is made to disappear by making the primary intermediate-molded article 3 deform freely according to inner residual stress which has generated the primary intermediate-molded article 3 by heating the primary intermediate-molded article 3 up to the temperature which is higher by 20-60 deg.C than the mold temperature of the primary mold 2. Then a container 7 is obtained by orienting again the secondary intermediate-molded article 5 through a secondary mold 6. The mold temperature of the secondary mold 6 is highly by the extent of several degrees than a utility atmospheric temperature of the container 7 which is set through heating, through which the container 7 having no residual distortion and high heat resistance is obtained.</p> |
