| 摘要 |
A pour spout seal construction for a gable top, thermoplastic coated type paperboard carton for packaging liquids. To permit easy unfolding of the folded pour spout within the top of the sealed carton by the consumer, the prior art has used adhesives to reduce the strength of the seal between the spout interior surfaces which are in surface contact with portions of the roof panels. In this invention, the opening action is different. Upon initial opening of the carton and subsequent unfolding of the pour spout, adhesive coating layers on the pour spout (located in positions homologous to the prior art adhesive coating layers) separate from the thermoplastic coating on the pour spout, instead of adhesive layers separating from themselves. Alternatively, the adhesive coating layers on the gable roof panels separate from the thermoplastic coating on the gable roof panels. In either case, the action is such that the adhesive coating layers stick to themselves upon pour spout unfolding. This invention does away with the need for adhesives, the latter sometimes permitting leaking and hence unsuitable for aseptic or so-called extended shelf life liquid packaging.
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