Abstract: A method for joining a lid to a container includes the formation of interlocking waves of material at the location where the lid joins the container. The interlocking waves are geometrically aligned relative to the interior of the container so as to maximize the burst strength of the container and minimize the peel strength of the lid from the container.

Abstract: A method and apparatus are disclosed for heat sealing two thermoplastic parts by clamping the parts together with a cooled clamp so that the edges of the parts are exposed and melting the edges together by contacting them with a hot seal head wherein a layer of a protective material is interposed between the hot seal head and the parts to be sealed.

Abstract: An oxygen barrier blend for use in containers requiring good oxygen barrier properties which comprises more than 70% of an ethylene vinyl alcohol copolymer and the balance an amorphous nylon having no melting point. Such a blend is used in a laminate structure which can be thermoformed into such oxygen barrier containers.

Abstract: A laminate, a method for making the laminate and articles formed from the laminate are disclosed. The laminate comprises an outer layer, an optional adhesive layer, an inner layer, an intermediate regrind layer formed of a blend of the materials from which the other layers are formed, and, interposed between the outer layer and the intermediate regrind layer, there is a buffer layer which is formed from a blend of the materials from which the outer layer and the intermediate regrind layer are formed and which comprises at least about 5% of the material of the intermediate regrind layer. The outer layer is preferably polypropylene and the inner layer is preferably an ethylene vinyl alcohol copolymer.

Abstract: A method for converting a thin-walled container to a jar with a rigid threaded neck which will accept a conventional threaded screw cap which comprises separately forming a thin-walled container and a rigid threaded neck ring and then attaching the ring to the outside of the container and the jar so made.

Abstract: A method and apparatus are disclosed for the fabrication of an openable container lid wherein a failure zone opening is defined about the desired location of a future opening in the lid, and simultaneously with this operation the lid is joined to the flange of the container. The combination of both of these steps at a single work station minimizes the equipment necessary to attach a lid to a container.

Abstract: A laminate, a method for making the laminate and articles formed from the laminate are disclosed. The laminate comprises an outer layer, an optional adhesive layer, an inner layer, an intermediate regrind layer formed of a blend of the materials from which the other layers are formed, and, interposed between the outer layer and the intermediate regrind layer, there is a buffer which is formed from a blend of the materials from which the outer layer and the intermediate regrind layer are formed and which comprises at least about 5% of the material of the intermediate regrind layer. The outer layer is preferably polypropylene and the inner layer is preferably an ethylene vinyl alcohol copolymer.

Abstract: This invention relates to a method and apparatus for making cupped articles from thermoplastic sheet or billets wherein the articles are formed with a bellows bottom which will displace inwardly when the internal pressure within the cup decreases. The invention specifically relates to an improvement upon the forming process which involves clamping a heated sheet or billet of a thermoplastic material in the solid phase state between a forming plug and a hollow mold having an end opening, moving the forming plug into the opening to carry the sheet into the mold, and introducing pressure fluid into the stressed portion of the sheet to form the article by making the sheet conformed to the shape of the hollow mold. The closed end of the hollow mold is improved by forming it with a flat central portion which has a tapered portion extending outwardly therefrom.

Abstract: The invention is a thermoplastic lid which utilizes a bellows action to prevent paneling in the thermoplastic container to which it is attached. The lid comprises a flange for attachment to the container and a recessed center portion which has a flex area comprising a raised ridge adjacent to the outer ridge of the center portion. The stiffness of the lid and the thickness of the flex area are no greater than the maximum which will allow the center portion of the lid to flex inwardly sufficiently to provide the minimum displacement of head space necessary to prevent paneling.

Abstract: A method for converting a thin-walled container to a jar with a rigid threaded neck which will accept a conventional threaded screw cap which comprises separately forming a thin-walled container and a rigid threaded neck ring and then attaching the ring to the outside of the container and the jar so made.

Abstract: A self lubricating nut having a central cavity for insertion of a bolt, a lubricant passage through said nut which opens into an internal bored circumferential gland, and at least one internal bored axial gland which crosses said circumferential gland.

Abstract: A process is disclosed for thermoforming a sheet or billet comprised of at least one outer layer of polypropylene and at least one adjacent layer of a random copolymer of propylene and ethylene and, optionally, a barrier layer. The sheet or billet is thermoformed into rigid articles which do not significantly distort under retort conditions by forming the sheet or billet at a temperature below the sticky point of the polypropylene layer and above the sheet distortion temperature.

Abstract: A multilayer structure and container formed therefrom is disclosed which comprises a layer of a polystyrene polymer modified with a carboxylic acid or carboxylic anhydride and a layer of an ethylene vinyl alcohol copolymer.

Abstract: This invention encompasses a process for making containers from multiple stacked billets which comprises the steps of preparing thermoplastic sheet, cutting or punching billets from the sheet, stacking two or more of the billets together, heating the stacked billets or the mating surfaces of the billets to or above the fusion temperature of the mating surfaces, where the billets adhere to each other, and thermoforming the stacked billets into containers.

Abstract: This invention encompasses a process for making multilayer containers by conventional roll fed sheet method, with minimal scrap loss, which comprises the steps of preparing a monolayer sheet of a first thermoplastic material by conventional roll fed sheet methods, cutting or punching billets from a second thermoplastic material sheet, heating the monolayer sheet and the billets to a temperature where both the sheet and the billets become tacky, placing the billets at a position on the sheet so that the billets are in a position over forming cavities in a forming mold at the time of forming, while maintaining the billets and sheet at a temperature where the sheet and billets are tacky and weld together, and forming containers from the welded billets and sheet so that the web scrap left after forming is pure monolayer sheet.