摘要 |
A method of preforming a cover for a can, the cover is formed from a planar base having a metallic barrier layer and resin layers on either side thereof. The base is first premolded to have a flat bottom recess, a cylindrical sidewall, and preferably an upper flap portion. In the premolding the base is stretched no more than by a factor of 1.8. Then a resin is injection molded over the premolded base to form either a uniform bottom cover or a top cover with a tab. |