Flat top end closure for liquid containers

Claim 1

In a flat top end closure for a liquid carrying, thermoplastic-coated paperboard container having a tubular body and including two oppositely disposed infolded panels and two oppositely disposed outer closure panels, one of said infolded panels adapted to serve as a pouring spout, said infolded panels each including a substantially triangular panel portion defined by converging diagonal score lines and being integrally connected to said tubular body, and a first pair of fold-back panels integrally connected to and folded between each of said substantially triangular panel portions and the respective adjacent outer closure panels, said two oppositely disposed outer closure panels including one shorter and one longer panel, with the edge portion of said longer panel overlapping the edge portion of said shorter panel and each having a diagonal opening-assist score line formed thereon and overlying said respective converging diagonal score lines to form a second pair of fold-back panels between said respective diagonal opening-assist score lines and said first pair of fold-back panels, a first lift tab formed on a side edge of said longer panel for lifting the portion of said overlying longer panel adjacent its diagonal opening-assist score line and the integrally connected underlying fold-back panel of said pouring spout, and a second lift tab formed on the other of said fold-back panels of said pouring spout for lifting said other fold-back panel and the portion of said overlying shorter closure panel adjacent its diagonal opening assist score line to enhance the opening of the infolded panel bearing said second lift tab into said pouring spout, the improvement comprising a first layer of a suitable abhesive material applied to the outer surfaces of said pouring spout and said second lift tab except for a portion immediately adjacent the outer edge of the integrally connected underlying fold-back panel which does not include said second lift tab, said portion being sealed to the adjacent inside surface of said second lift tab; a second layer of said suitable abhesive material applied to substantially the entire inner surfaces of one of said pairs of fold-back panels of said infolded panel bearing said second lift tab and of said outer closure panels intermediate said first pair of fold-back panels and said respective diagonal opening-assist score lines; and a sealant applied laterally across the inside surface of the portion of said longer outer closure panel between its diagonal opening-assist score line and said side edge on which said first lift tab is formed, substantially aligned with the free cut edge of the integrally connected underlying fold-back panel which does not include said second lift tab, in order to overlie and effectuate the sealing off of the crevice between the adjacent edges of the integrally connected underlying fold-back panel which does not include said second lift tab and the fold line formed between the fold-over panel and the shorter top closure panel, the second layer of said suitable abhesive material on said longer outer closure panel being terminated at the edge of said sealant.