Freezer to microwave oven bag
AssigneeThe Dow Chemical Company
InventorFred Stevenson
Life of this patent
Estimating the term…
Abstract
A disposable or reusable and reclosable thermoplastic bag capable of being compactly stored as a food container in freezers, yet capable of standing with an upright spout in a microwave oven for non-spill thawing and cooking of food contained in the bag. The bag is formed of two wing-shaped pouches on either side of the upright spout. The preferred closure is a zipper type which can automatically vent upon softening of its thermoplastic structure during the cooking stage. The bag preferably has inner and outer skin layers of different heat-softening temperature responses so that peripheral sealing is effected only with the inner layers, allowing the wing-shaped pouches to be formed out of a gussetted bottom without sealing of the outer layer plies facing one another.
Claims28
A process for forming a bag having a neck portion and adjacent opposed wing pouches, said neck portion being a minor portion of the bag, the process comprising the steps of providing thermoplastic film material for the bag having inner and outer skins of different heat-softening temperature responses, selecting the inner skin so as to have a significantly lower heat-softening temperature than said outer skin, laying over two plies of said film against one another so that inner skin abuts against itself and forms opposite sides and a bottom, gussetting the bottom of said film to the extent that the gussetted bottom forms the major portion of the bag, applying heat along opposite margins of said sides of a temperature above the softening temperature of said inner skin but below that of the outer skin, whereby sealing of the inner skin along said margins occurs without sealing of adjoining outer skin along the gussetted bottom of the bag, forming wing pouches from the gussetted bottom immediately adjacent and below the neck portion with the opposed wing pouches being joined at their margins only at their juncture with the base of the neck portion such that the bottom of the bag formed by the opposed wing pouches sets essentially flat when used, and the non-gussetted section forming a central neck portion in open communication with said wing pouches.
A flexible thermoplastic film bag having opposed base wing sections and a central neck portion extending upwardly from between the base wing sections, said neck portion having an internal channel in open communication with said wing sections and providing access to said wing sections when the bag is opened, said wing sections being pillow-shaped and of a size to permit substantially all the product for which the bag is designed to hold to be contained therein, said neck portion being of a length sufficient for filling, folding and use without spilling but yet being a minor portion of the bag and free to be folded to permit compact stacking while maintaining a spill free, lay-flat bag configuration when in use.
A flexible container of thermoplastic film, said film comprised of an inner layer and an outer layer, said film folded upon itself and gussetted at its bottom so that surfaces of the inner layer face one another, the gussetted bottom comprising the major portion of the bag, the facing surfaces of the inner layer at the margins of the film sealed together to close the sides of the container, said gussetted bottom forming adjacent wing pouches, said film above said gussetted bottom comprising a minor portion of said container and forming a central neck having a channel permitting access into said wing pouches, said neck being of sufficient height for filling, folding and using while maintaining a spill-free, lay-flat bag configuration.
Dependencies are inferred from the claim text.