Abstract: An improved method for forming closed burstable pouches having breakable seals. The method includes selection of a laminated polymeric film which has two principal layers--an outer layer which is responsive, and an inner layer which is non-responsive, to a radio-frequency (RF) welding field, the inner layer being of a biaxially-oriented polymeric material such that its cohesive strength in its thickness direction is less than the cohesive strength of the outer layer. The outer layer has a higher melting point than the inner layer. With two sheets of such material placed with their inner surfaces in contact, the breakable seal is formed by applying an RF welding field for a time and at an intensity to heat the outer layers sufficiently to fuse the inner layers by heat transfer from the outer layers without melting the outer layers and without destroying the biaxially-oriented structure of the inner layer.
Abstract: Multi-layered enclosures are provided which include extruded tubing laminated between two extruded sheets of coextruded film in order to rapidly produce an unusually tough enclosure having longitudinal side walls that are free of internal seams while providing superior fluid barrier properties. When desired, the multi-layered enclosure is transformed into a multi-layered bag or pouch by sealing the multi-layered enclosure together along one or more locations interconnecting the longitudinal or side edges of the multi-layered enclosure to thereby cross seal together the sheets, the tubing, and the internal surfaces of the tubing.
Abstract: An impulse-action heat-sealer for manufacturing a sealed article, as a bag or the like, by pressingly keeping the portions to be sealed and effecting the sealing by means of heating with short-time electric current. The sealer has a pressing-sealer lever as is actuated electromagnetically, and is further equipped with an air-damper to function as a buffer for the actuating movement of the pressing-sealer lever.
Abstract: Multi-layered enclosures are provided which include extruded tubing laminated between two extruded sheets of coextruded film in order to rapidly produce an unusually tough enclosure having longitudinal side walls that are free of internal seams while providing superior fluid barrier properties. When desired, the multi-layered enclosure is transformed into a multi-layered bag or pouch by sealing the multi-layered enclosure together along one or more locations interconnecting the longitudinal or side edges of the multi-layered enclosure to thereby cross seal together the sheets, the tubing, and the internal surfaces of the tubing.
Abstract: An improved, tough, opaque laminate structure, particularly useful for incorporation into packaging for light-sensitive photographic products. The laminate comprises a polyisobutylene-modified, high-density polyethylene layer which is sandwiched between two layers of linear low density or linear medium density polyethylene.
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.
Abstract: A short dwell indexing drive system for intermittently moving a web of thermosealing material through a bag machine includes a conjugate cam defined by a pair of disc cams on a continuously driven input or cam shaft which engage cooperating groups of cam followers on an intermittently driven output shaft that yields one web draw/dwell cycle for each revolution of the cam shaft. In the preferred embodiment the contour of the cams smoothly index the web by first accelerating the output shaft from zero velocity through a relatively low peak velocity and thereafter decelerating the web to zero velocity at a point in the cycle in excess of 180.degree. before the output shaft is held stationary to the end of the cycle during a dwell period. Belt drives and an adjustable jackshaft which allows the use of different pulley ratios are connected between the output shaft and a web engaging draw roll for amplifying or reducing motion of the output shaft and for providing articles such as bags of different sizes.
Abstract: A pouch-packet having walls with V-shaped or Y-shaped separation-enhancing deformations formed therein, and the method and apparatus for making the same are disclosed herein.
Abstract: Hot melt adhesive is applied to a moving substrate in a pattern including at least two lines which extend transversely to one another, by conveying the substrate past a nozzle orifice through which a first line of molten adhesive is applied, as by extrusion, to the substrate parallel to the direction of substrate movement and, while continuing to move the substrate in the same direction, projecting another portion of the molten hot melt adhesive onto the substrate as a burst in the form of a flat sheet issuing from a fan spray orifice, this orifice being oriented so that the sheet is projected transversely to the direction of substrate movement, and terminating the burst so rapidly that the adhesive so projected is deposited on the moving substrate in the form of a line having a length in the crosswise direction that is several times its width.
Abstract: A mattress includes a flexible tube having a pair of major surfaces alternating with a pair of side surfaces with marginal portions of the major surfaces extending beyond the side surfaces at each end of the tube. The marginal portions are bent toward each other and lap sealed along seams extending substantially between the side surfaces to form the end surfaces of the mattress. At each corner an insert is disposed along a line where the end surface approaches the side surface and is attached thereto by a continuous lap seam having substantially parallel sides extending substantially between the major surfaces. An associated method includes the provision of a special mandril for heat sealing the insert.
Abstract: A cover sheet is disposed over a recess in a work table. A folding apparatus, including an edge folder and edge erector is disposed over the recess and lowered until the edge erector is in the recess. The edge erector includes horizontally movable plates which are moved outwardly against the edges of the recess to erect the marginal edges of the sheet. The edge folder has downwardly depending, horizontally moving members. The edge folder is lowered until the members touch the work table after which the members are moved inwardly to fold the erected marginal edges of the sheet horizontally over the plates. The plates are then withdrawn while the edge folder members are maintained in contact with the folded marginal edges, and high frequency heat applied to weld the folded marginal edges to the sheet. After the welding is completed the edge erector and edge folder are raised to their initial position and the members are returned to their outward positions.