Abstract: An apparatus is provided for continuously sealing a thermoplastic draw tape to a thermoplastic bag at a sealing section. The bag forms one of a plurality of bags formed on a continuous web of thermoplastic material. The bag includes a hem defining a channel wherein the draw tape is disposed. The section of the bag which includes the hem and the tape thus includes a plurality of layers of thermoplastic material. The apparatus comprises a conveyor for continuously moving the web; a first sealing station for forming a heat seal through at least two of the layers of the hem and tape, the seal being formed on a first side of the bag; and a second sealing station for forming a heat seal through the rest of the layers of the hem and tape at the sealing section on a second side of the bag. The first and second sealing stations form the seals while the web is continuously moved by the conveyor.

Abstract: Apparatus and methods for manufacturing draw tape bags from a web of plastic material are disclosed. The apparatus and methods relate to draw tape bags in which a hem seal, enclosing the draw tape, is formed in the bag without stopping the movement of the web through the hem sealing station.

Abstract: A stackable grid material for soil confinement is disclosed. The grid material comprises repeating pattern of cell structures with thin cell walls in between cells and open cell tops and bottoms. The cell wall material of the grid is notched such that the top edges of the cell wall material on the perimeter of a lower layer of grid material overlaps with the bottom edges of cell wall material on the perimeter of an upper layer of grid material. The internal cell walls are able to rest on top one another in spite of the overlap at the perimeter walls due to the positioning and shape of the notches.

Abstract: Multiple layer nonoriented heat sealable films are disclosed having a base substrate layer of poly(ethylene terephthalate) (polyester) or polyester copolymer and at least one heat sealable surface layer of a copolyester. The films are prepared by conventional cast or blown film coextrusion techniques.

Abstract: The present invention is a frame for installing a grid section of cells of a grid confinement system for soil. The frame is generally planar having holding members on two sides to engage the grid section of cells. Each holding member can be independently controlled to engage or disengage the grid section of cells. Also, the frame is ventilated. The frame facilitates road center line reference, edge cell interlock and underwater installation.

Abstract: A nonoriented, heat sealable, coextruded, moisture barrier film is disclosed. This film has a base layer ("A") of polypropylene homopolymer, polypropylene copolymer or combinations thereof, a heat sealant layer ("C") of polyester/copolyester or blends thereof and a tie layer ("B") of modified polyethylene homopolymer, modified polyethylene copolymer, modified polypropylene homopolymer, modified polypropylene copolymer, an unmodified polyethylene copolymer or combinations thereof between the base layer ("A") and the heat sealant layer ("C"). This film has three layers ("ABC") or five layers ("CBABC"). This film exhibits a very broad heat seal range and has a moisture vapor transmission rate of from about 0.20 to about 1.0 g/100in.sup.2 /24 hr. This film has a wide variety of applications as a packaging film including such demanding uses as the inside of a microwave popcorn bag. This film significantly improves the shelf life of microwave popcorn compared to conventional films used for this product.

Abstract: A nonoriented, heat sealable, coextruded, moisture barrier film is disclosed. This film has a base layer ("A") of polyethylene, preferably high density, a heat sealant layer ("C") of polyester/copolyester or blends thereof and a tie layer ("B") of modified polyethylene homopolymer, modified polyethylene copolymer, unmodified polyethylene copolymer or combinations thereof between the base layer ("A") and the heat sealant layer ("C"). This film has three layers ("ABC") or five layers ("CBABC"). This film exhibits a very broad heat seal range and has a moisture vapor transmission rate of from about 0.20 to about 1.0 g/100 in.sup.2 /24 hr. This film has a wide variety of applications as a packaging film including such demanding uses as the inside of a microwave popcorn bag. This film significantly improves the shelf life of microwave popcorn compared to conventional films used for this product. This film also exhibits excellent heat seal properties to itself as well as a wide variety of diverse substrates.

Abstract: An ultrasonic welding tip assembly and associated method of use are described. The welding tips of the assembly may be conical with the cone height A and base width B having a ratio of A/B=1.2 or frusto-conical with a ratio of 0.76 in preferred embodiments. The welding tips are supported on anvils. In the welding process, the tips are only partially inserted into the material being welded so that the anvils remain spaced from the material. This space provides a reservoir into which molten material may flow away from the regions of the welding tips.

Abstract: Disclosed herein is a plastic wall-mounted dispenser primarily for coreless rolled sheet material and in which the plastic material, typically polypropylene, from which the dispenser is made is somewhat yieldable under stress. The dispenser is mounted in cantilevered relationship to the wall and the weight of the dispenser and its contents and pressures exerted thereagainst by the act of dispensing sheet material therefrom causes stresses which tend to twist the dispenser and open the latches by which the base and cover sections of the dispenser are latched together. To rigidify the structure, the base portion of the dispenser is formed in the shape of a hollow truncated pyramid which gives it an inherently strong beam configuration. The cover portion may also be formed in part in the shape of a hollow truncated pyramid.

Abstract: The red color of fresh red meats is preserved by adding thereto a color preservative selected from the group consisting of sodium cyanate, acetylurea, sodium-5-acetylhydantoate, urethylane sodium carboxylate and mixtures thereof. In a preferred embodiment, these color preservatives are incorporated in a resinous polymeric film which is fibrillated to provide an open-celled, microporous structure having a large internal surface area. Such films can be used as an interleaf between layers of slices of freshly cut red meat and are effective for preserving the fresh color for several hours.

Abstract: Normally hydrophilic inorganic fillers for polymeric resins are modified to enhance their dispersibility in such resins by admixing filler particles with a block copolymer of ethylene oxide and propylene oxide under shear and at an elevated temperature so as to coat the filler particles with a portion of the block copolymer. Thermoplastic polymeric resins, such as polyethylene and polypropylene, containing thus-modified fillers can be conventionally formed into products, such as thin film bags, having improved strength properties.

Abstract: Method and apparatus for detecting differences in the wall thickness of a hollow object at various locations around its perimeter. Radiant electromagnetic waves are directed through one side of the object. The intensity of the waves is sensed at two adjacent locations where they emerge from the other side of the object after the waves have passed through two wall portions of the object at different sides thereof. The intensity of said waves at said locations is compared to ascertain any difference in wall thickness at said locations. This comparison is repeated as the waves scan the perimeter of the object and the successive comparisons indicate any trend of wall thickness departure from an average thickness. Corrective measures can then be taken at the apparatus which fabricates the object to restore wall thickness to the desired amount. The invention has particular utility in monitoring and controlling wall thickness of extruded plastic tubing in the course of fabricating plastic bags.