Abstract: A multilayer laminate comprises a first perforated film of propylene homopolymer or copolymer, oriented heat set polyester or oriented heat set polyamide and a second film bonded to the first film and including a bonding layer of ethylene vinyl acetate copolymer or chemically modified ethylene unsaturated ester copolymer, a core layer of a heat resistant, breathable polymeric material, and an outer heat sealable layer. One or more filler layers may be included in the structure, located between the outer heat sealable layer and a polymeric adhesive layer.
Abstract: Laminated sheet material 9 comprises a laminate of a polyvinyl alcohol or other water-disintegratable film 12 with a thin coextruded film comprising a melt-bondable layer 15 and an impermeable layer 14. The laminate is odor impermeable but water disposable and so can be used to form a toilet-disposable ostomy bag by melt-sealing around the edges 10 between the facing melt-sealable surfaces 15.
Abstract: A multi-layer film useful in vacuum skin packaging and other vacuum packaging applications, and having a combination of good implosion resistance, formability and high oxygen barrier characteristics, includes a core layer having an oxygen barrier material, intermediate layers of EVA or other ethylene homopolymer or copolymers, polymeric adhesive layers which bond the intermediate layers to respective surfaces of the core layer, a first outer heat-sealable layer, a second outer heat resistant layer, and two moisture resistant layers disposed between respective outer and intermediate layers.
Abstract: A semi-rigid, heat-sealable laminate with permanent antistatic characteristics comprising a semi-rigid packaging material having a coating of heat-sealable antistatic plastic. The antistatic plastic is a film of a modified acid copolymer. The modified acid copolymer is selected from (I) a mixture of (A) a polymer containing carboxylic acid moieties and (B) an antistatically effective amount of a quaternary amine, or (II) the acid/base reaction product of (A) a polymer containing carboxylic acid moieties and (C) an antistatically effective amount of an organic or inorganic base.
March 6, 1990
Date of Patent:
November 12, 1991
W. R. Grace & Co.-Conn.
Marvin R. Havens, Stephen L. Fowler, William P. Roberts, Cynthia L. Ebner
Abstract: A packaging method and apparatus employ (i) a thermoforming station 6 through which a support film web 4 is advanced by means of an endless chain carrying clamps 16, followed by (ii) a loading station in which product articles are inserted into the trays formed by the thermoforming station, and (iii) a film-combining station II at which a covering film 3 is stretched longitudinally and then applied in its stretched configuration to the support web 4 (with or without the above-mentioned thermoformed trays) and is clamped thereto for subsequent vacuum skin packaging of the product articles between the support web 4 and the upper film 3. The resulting vacuum skin packs from such a process and apparatus are wrinkle free whereas the conventional vacuum skin packs exhibit longitudinal wrinkling in the covering film.
Abstract: Packaging apparatus, using an upper film (6) pre-heated before contact with a lower film (9) on which products (not shown) are placed, has at least the central region heated by radiant heaters (7) and the marginal regions heated by hot air nozzles (10) at least in the region immediately preceding contact (8) between the upper and lower films.
Abstract: A package is steam-shrunk while subjected to a substantially constant sub-atmospheric pressure generated by a suction fan 22 operating at the same time as a steam generator 13 maintaining the prevailing pressure within a chamber interior 20 at sub-atmospheric pressure in the presence of steam. The low pressure of the steam ensures that its temperature is well below the boiling point of water and avoids thermal damage to the material of a container 12 being shrunk.
Abstract: The film is formed by a composition comprising a mixture of 50-100 weight % of an ethylene-butyl-acrylate copolymer (EBA) having a content of butyl-acrylate (BA) of 5-50 weight %, and 0-50 weight % of an elastomeric polyolefin. Laminates comprising a layer constituted by said film have excellent characteristics of noiselessness and softness.
Abstract: A molded container includes body and cover portions and a hinge with a central thickened rib and relatively thin segments on either side of the rib. A means for initiating tear can be used to tear open the container along the hinge to provide quick access to the interior of the container.
Abstract: A multi-layer thermoplastic shrinkable film with improved processing properties comprising at least a heat sealing VLDPE layer, a core oxygen barrier layer and an outer thermoplastic layer, and also comprising interposed between the barrier and the outer thermoplastic layer a further intermediate VLDPE layer.
Abstract: A method of producing an oxygen barrier film, and the resulting film, includes the coextrusion of a multi-layer extrudate having an outside ethylene vinyl alcohol copolymer layer which has been passed through a hot water system to soften and wet the ethylene vinyl alcohol copolymer. The wetted film can be more easily oriented to produce a shrinkable film.
Abstract: Disclosed is a skin packaging film for skin packaging high profile and/or heavy articles. The film comprises linear ethylene/alpha-olefin copolymer. In one embodiment, the film is antistatic and may be employed for skin packaging of electro-static sensitive items such as circuit boards.
November 17, 1989
Date of Patent:
July 23, 1991
W. R. Grace & Co.-Conn.
Marvin R. Havens, Stephen L. Fowler, George J. McCrary, Jr., Alfred P. Engelmann
Abstract: Packaging apparatus and a method therefor, comprise a bag dispenser in which a stack of bags is supported on extensible wicket pegs and the leading bag is advanced from the stack to bag-receiving wicket pegs of bag-receiving retainer means while the extensible parts of the wicket pegs of the stack holder means are extended into engagement with the wicket pegs of the bag-receiving retainer means. In that configuration a suction pad can draw the nearest bag from the rest of the stack to a separated position from which it may be further advanced by mechanical means and/or an air jet to pass that bag from the extensible wicket pegs of the stack holder means on to the wicket pegs of the bag retainer means. The bag dispensing apparatus may comprise part of a packaging apparatus.
Abstract: This invention relates to films made from vinylidene chloride copolymers. Specifically, this invention relates to a method and composition for lowering the oxygen permeability and enhancing the thermal stability and enhancing the melt shear stability of packaging films having a layer of vinylidene chloride copolymer film by adding a processing aid such as an epoxy resin to vinylidene chloride copolymer of low molecular weight. The conventional stabilizer/plasticizer combination of epoxy resin and 2-ethyl-hexyl diphenyl phosphate may be employed with the vinylidene chloride copolymer. The layer of vinylidene chloride copolymer can be as thin as 0.18 mil.
Abstract: Disclosed is a thermoplastic polymeric composition having antistatic characteristics and a method to make same. The composition comprises a thermoplastic polymer in admixture with an antistatic agent. In one embodiment the polymer is nylon 12 and the agent is N-butyl benzenesulfonamide. Also disclosed is the antistatic polymeric composition in a film, which is useful for packaging static sensitive devices such as electronic circuit boards, or for packaging devices that must be protected from static electricity such as devices in a medical operating room where explosive oxygen and/or ether are present.
Abstract: A first web having an ionomer, or ionomer/ethylene vinyl acetate copolymer (EVA) sealant layer, heat sealed to a second web having an EVA/ethytlene butene copolymer (EBC)/polypropylene (PP) sealant layer, forms an easily opened package. A layer adjacent the sealant layer of the second web optionally includes PP or ethylene propylene copolymer. With this optional layer, the sealant layer of the first web may comprise a polymeric material which forms strong interweb adhesion upon heat sealing.
Abstract: Disclosed is a film having antistatic characteristics and a method to make the film. The film comprises a blend of polyether block amide copolymer with an aromatic sulfonamide antistatic agent.
Abstract: An easily opened package is made by heat sealing a first web to a second web. The sealing layer of the first web is a blend of polybutene and polypropylene with a third polymeric material of ethylene vinyl acetate copolymer. Low density polyethylene, linear low density polyethylene, or ionomer. The sealant layer of the second web is ethylene vinyl acetate copolymer, low density polyethylene, linear low density polyethylene or ionomer.
April 12, 1990
Date of Patent:
June 11, 1991
W. R. Grace & Co.-Conn.
Gregory R. Pockat, Carl C. Christenberry, Paul J. Satterwhite
Abstract: The multilayer shrink film of the present invention provides very low shrink tension approximating some PVC films, while providing relatively high free shrink characteristics and relatively low shrink temperatures. The preferred film has three layers including a relatively thick core layer comprising a polymeric material or blend of polymeric materials having a relatively low melting point, typically less than about 100.degree. C., two outer layers comprising a polymeric material or blend of polymeric materials having a relatively high melting point, typically greater than about 100.degree. C., the material of the outer layers having a melting point at least about 10.degree. C. higher than the melting point of the material of the core layer.
Abstract: A seamless, bone puncture resistant bag is provided that representatively includes a length of lay-flat seamless tubular film folded to a double lay-flat configuration and having all adjacent film surfaces interfacially bonded, respectively, except at one outermost interface. The configuration thus forms a seamless envelope with one face thickened integrally to triple thickness. In a less preferred mode, a similarly reinforced bag is provided but which has either an end-seal or side-seals. Associated methods for making such bags are also provided.