| 摘要 |
1362482 Containers ALUMINUM CO OF AMERICA 25 Sept 1972 [19 Oct 1971] 44253/72 Heading B8D [Also in Divisions B3 and B5] A metal container wall 40, Fig. 5, has a protective coating 44 consisting of a copolymer of a polyolefin and ethylene or an ionomer secured to the wall by an epoxy, polyester or polyurethane adhesive 42, the wall being scored 54 defining a removable sector and reducing the thickness of the coating 44 beneath the score line. An aluminium or steel wall 40 for a can, bottle, jar &c. may be provided with a coating 44 of polyethylene acrylate or polypropylene ethylene copolymer, having an ethylene content of 2-10 weight per cent. The adhesive 42 may be applied at 1-5 mg./sq. ins. and the bond cured at 150-475‹ F. for 10-60 minutes. Lamination is effected at a metal temperature of 180-300‹ F. Improved adhesion occurs if the layer 44 has been treated electrostatically. The coating 44 has an initial thickness of 1À5- 4 mils., being subsequently reduced by 10-50% beneath the score lines. Thicknesses of 0À009- 0À0145 ins. for the metal and 0À002-0À006 ins. beneath the score line are referred to. |
