Abstract: A method and system for preparing flat bottom thermoplastic sacks comprising process steps and means for forming a tube of thermoplastic film, collapsing said tube while forming two oppositely disposed gussets therein, forming two pairs of diagonal sealed seams in the gussets, forming a transverse sealed seam across the tube along a line which includes the inboard ends of the diagonal seams and forming preweakened transverse lines closely adjacent to said transverse sealed seam or forming a severing line along this line, removing the four double triangular regions bounded by the diagonal seams, the transverse seams and the side edges of the tube and collecting the resulting structures either while still interconnected or by stacking the severed sacks. The final structure can have handles or it can be handleless.

Abstract: A thermal plastic film bag structure having front and rear walls, gusseted side walls and a sealed bottom. This bag which has a tendency to form holes in the bottom at the seal transition point between the four layers of the gusset and the two layers of the central region of the bag is improved by providing seal areas, e.g. circular seals which are located slightly above the bottom seal line and slightly inside of the vertical line formed by the innermost reach of the gussets on both sides of the bag. The seal areas relieve strain at the weak regions in the bottom of the bag.

Abstract: A bag pack including a plurality of stacked bags each bag having loop handles which are integral extensions of the front and rear walls of the bag. Between the handles are a pair of superimposed single film tab members extending above the front and rear bag walls and above the open mouth portion of the bag. The front tab is coplanar with the front wall and either (1) completely unconnected thereto or (2) weakly connected thereto. The rear tab is coplanar with the rear wall and connected thereto through a localized line of film weakening which is comparatively stronger than (2) above. The individual bags may be bonded together through the tabs. The pack has suspension means in association therewith.

Abstract: The present invention relates to a collection of ultra-thin bags and a collection of bags per se wherein said bags are made by providing two separated thermoplastic films; forming transversely across each separated film, lines of weakness extending from one edge of each film to the other, with each line spaced from the next a bag length distance apart; bringing the films together in face-to-face relationship with the lines of weakness across one film in registration with those of the other films; sealing the films transversely along lines parallel with and immediately adjacent to the lines of weakness; slit-sealing the film layers at one or more bag width intervals to complete individual but interconnected bag structures; and collecting each strip of interconnected bags into a volumetrically efficient form.

Abstract: A bag pack of a plurality of stacked bags made from thermoplastic film, each bag comprising front and rear walls; a bottom; an open-mouth portion, said open-mouth portion being characterized by having handles which are integral extensions of said walls and located at opposite ends of said bag mouth portion. A single film tab member extends above each rear bag wall and above the open-mouth portion. The tab is coplanar with the rear wall and connected thereto through a localized line of film weakening. The tabs of all bags are in registration and are a collection of only tabs coplanar with said rear walls. The tabs are bonded together and include a suspension means to accommodate physical suspension of the pack.

Abstract: An annular extrusion die for the production of a tubular thermoplastic film web material, such as an annular extrusion die including a filtering arrangement for the formulation of a more consistently or uniformly distributed polymer melt conveyed to the die orifice of the extrusion die which will impart improved properties to the extruded thermoplastic film material. Also disclosed is a method of producing an improved extruded thermoplastic film web material through the utilization of the inventive extrusion die arrangement. A cavity or die flow chamber within the body of the annular extrusion die is filled with a particulate inert material of either uniform granular size or of random sizes, so as to force the polymer melt being conveyed towards the die orifice to randomly flow through the interstices which are present between the particles of the granular material, and thereby uniformly fill the cavity.

Abstract: A method for preparing flat bottom thermoplastic sacks comprising process steps for forming a tube of thermoplastic film, collapsing said tube while forming two oppositely disposed gussets therein, forming two pairs of diagonal sealed seams in the gussets, forming two pairs of diagonal preweakened lines parallel to said diagonal seals, forming a transverse sealed seam across the tube along a line which includes the inboard ends of the diagonal seams and forming preweakened transverse lines closely adjacent and parallel to said transverse sealed seam or forming a severing line along this line, removing the four double triangular regions bounded by the diagonal preweakened lines, the transverse preweakened lines and the side edges of the tube and collecting the resulting structures either while still interconnected or stacking the severed structures and then removing the triangular regions. The final structure can have handles or it can be handleless.

Abstract: Method and system for preparing a flat-bottom thermoplastic sack including forming a transverse sealed seam across the mid-section of a collapsed, gusseted tube and simultaneously or subsequently forming a preweakened transverse line closely next adjacent to the sealed seam; forming diagonal sealed seams of each 2 ply gusset fold so as to meet the ends of the transverse sealed seam and removing the four double-film triangular regions outside of the diagonal seams and separating said structures along the preweakend lines to form individual flat bottom sacks. The process also includes forming a handled version of the same sack.

Abstract: A method for producing an internally reinforced aeolotropic thermoplastic film web through coextrusion of two polymeric materials, and more particularly, a method of forming a film web possessing an enhanced tensile strength in at least the longitudinal or machine direction of the film web. A plastic film having internal striplike reinforcements entirely embedded within a matrix material is formed by the inventive method, and such film is utilized for various articles; for instance, plastic bags, bag components such as handles by liners, stretch wrap film, and the like.

Abstract: A method and system for preparing flat bottom thermoplastic sacks comprising process steps and means for forming a tube of thermoplastic film, collapsing said tube while forming two oppositely disposed gussets therein, simultaneously or spatially sequentially opening a gusset fold on each side of said collapsed tube to their full, lay-flat extent; simultaneously or spatially sequentially forming in each of the four gusset folds, a diagonal sealed seam over the portions of the tube width corresponding to the gussets along lines diagonal to the length of the tube so that the ends of the sealed seams of adjacent gusset folds are at least closely spaced or in contact so as to form an angle of at least approximately 90.degree.

Abstract: A bag structure of a thermoplastic film material comprising front and rear bag walls connected by side walls and having an open mouth top portion, said open mouth portion being characterized by having handles located at opposite end regions thereof, said handles being of two films as a result of being integral extensions of said front, rear and gusseted side walls; said bag having a bottom wall planarly extensible so as to form a rectangle with at least no substantial excess film outside of the bulk volumetric capacity of said bottom region of said bag.

Abstract: A bag pack of a plurality of stacked thermoplastic bag structures each bag comprising a front and rear bag wall and an open mouth top portion. Handles are integral extensions of the bag walls. The bags are bonded together via bonding means in association with said handles. Individual bags may have stress relief curves in the handles and the bag mouth opening.

Abstract: A bag pack and individual bags characterized by having handles which are integral extensions of the front and rear of said bag. The bags have a bag mouth which includes stress relief curves on both sides of an upwardly extending tab. The tab includes at least one orifice which is positioned to create comparatively narrow webs which serve to be the tear-off points severing individual bags from the pack. The bags are bonded together via said tab at areas adjacent said orifice.

Abstract: The present invention relates to thermoplastic bag structures which are characterized by having a pair of carrying handles formed integrally with the bag walls and extending upwardly from opposite sides of the open mouth portion of the bag. Specifically, such handled bags are particularly characterized in having reinforced handle members where the handles comprise at least two layers of thermoplastic material, one of the layers imparting tensile strength to the individual layer and the other layer particularly employed to provide the requisite puncture and tear resistance necessary in such a bag structure.

Abstract: A thermoplastic bag characterized by having handles formed on opposite ends of the bag mouth which is characterized by having structural features immediately adjacent the mouth of the bag to provide stress relief at those positions on the bag mouth where maximum stress is concentrated when such bags are being filled with product and eventually carried by the user. The stress redistribution feature is characterized by an area or areas, immediately adjacent the mouth portion of the bag and the base of the handle members, which are characterized by having a plurality of narrow pleats which are impressed into the bag structure by die members during formation of the individual bag.

Abstract: A thermoplastic bag characterized by having handles formed on opposite ends of the bag mouth which is characterized by having structural features immediately adjacent the mouth of the bag to provide stress relief at those positions on the bag mouth where maximum stress is concentrated when such bags are being filled with product and eventually carried by the user. The stress redistribution feature is characterized by an area or areas, immediately adjacent the mouth portion of the bag and the base of the handle members, which are characterized by having a plurality of narrow pleats which are impressed into the bag structure by die members during formation of the individual bag.