Abstract: The open edge of a plasticboard is moved into a heating and sealing unit having a metal form with a U-shaped cross-section. A spacing tape and a release tape line the metal form. An induction or resistance heater is coupled to the metal form to raise the temperature thereof and heat the open edge to form a molten plastic edge wall, with the outer edges of the edge wall in sealing engagement with the form. The molten plastic fills the cavity between the form and the edge wall and forms a solid, continuous end wall upon cooling of the molten plastic. A batch sealing unit has a form moved directly into engagement with the edge wall to be sealed. A continuous sealing unit has an elongated form. A conveyor moves the plasticboard through the form in a continuous flow path with the form inclined to the path of the edge board to establish relative lateral movement. A cooling unit cools the end wall as the board moves from the form.

Abstract: A method of bonding areas of two elements of a sheet molded compound to form a bonded product includes intimate mixing of a thermoset epoxy or polyurethane adhesive with submicron particles selected from the group of gamma Fe.sub.2 O.sub.3 and magnetic iron oxide Fe.sub.3 O.sub.4, with the particles typically being 5 to 40% by weight of the final adhesive mixture to form a semi-liquid adhesive mixture. A bead of the adhesive mixture is located between the elements to be joined, and the elements are forced toward each other to compress and spread the semi-liquid adhesive mixture to form a flattened bonding element in intimate contact with the surfaces to be joined with an accurately controlled typical thickness of the adhesive of 0.005 inches to 0.2 inches. An induction coil is coupled to the elements and energized with a high frequency current of a frequency of from 1.5 to 8 MHz for a total period of about thirty seconds.

Abstract: An integrated multiple particle heating agent is provided for heating, particularly using the agent for heating and bonding plastic substrates. The integrated multiple particle heating agent includes significant portions of non-conductive ferromagnetic oxide particles which generate heat because of hysteresis losses and of conductive ferrous particles which generate heat because of eddy current losses. The dual particles are thoroughly intermixed and respond to a magentic field of an appropriate RF frequency. The ferromagnetic particles are submicron size and the ferrous particles are micron size. The particles are combined with an inert resin carrier and applied as a coating, directly incorporated within the substrate, or as a separate element. The ferromagnetic oxide loading is generally less than the ferrous particle loading, with a range of 30 to 60 percent (40 to 50 preferred) by weight of ferrous particles and a range of 10 to 50 percent (15-25 preferred) by weight of the oxide particles.

Abstract: An integrated multiple particle heating agent is provided for heating, particularly using the agent for heating and bonding plastic substrates. The integrated multiple particle heating agent includes significant portions of non-conductive ferromagnetic oxide particles which generate heat because of hysteresis losses and of conductive ferrous particles which generate heat because of eddy current losses. The dual particles are thoroughly intermixed and respond to a magnetic field of an appropriate RF frequency. The ferromagnetic particles are submicron size and the ferrous particles are micron size. The particles are combined with an inert resin carrier and applied as a coating, directly incorporated within the substrate, or as a separate element. The ferromagnetic oxide loading is generally less than the ferrous particle loading, with a range of 30 to 60 percent (40 to 50 preferred) by weight of ferrous particles and a range of 10 to 50 percent (15-25 preferred) by weight of the oxide particles.

Abstract: A preformed flock lined rubber-like glove has its cuff folded back to expose the flocked lining and is mounted in a rotating support. A spray nozzle deposits a band of the hot-melt adhesive on the flocked lining of the exposed and rotating cuff. The hot-melt adhesive is a combination of a hot-melt adhesive resin and a uniform dispersion of small particles which create heat in the presence of a high frequency magnetic field. The hot-melt adhesive is allowed to solidify to a solid mass. The glove is telescoped downwardly onto a polyethylene sleeve supported on a rigid form and the cuff is unfolded to place the adhesive into engagement with the sleeve. A high frequency unit includes a high frequency coil having a pair of conducting bars at least one of which is movable. The glove and sleeve subassembly is clamped between the conducting bars and the coil is energized from a high frequency source. The fine particles are activated to heat the hot-melt band simultaneously with application of pressure.

Abstract: A heat sealing apparatus for bonding plastic tubular members includes a seamless, tubular, elastic heating element encircling the plastic members. In one form, an annular inflatable bladder filled with hydraulic fluid encircles the heating element, and includes a rigid outer wall and an elastic inner wall that is bonded to the outer surface of the heating element. When the bladder is pressurized the heating element is compressed inwardly to a bonding position against the plastic members. The plastic members are then heated to a bonding temperature by the heating element resulting in a fusion bond along their interface. When the bladder is evacuated the heating element opens outwardly to be spaced from the plastic members to allow removal of the sealed members. The heating element includes a uniform dispersion of susceptor particles that will generate heat when exposed to the high frequency magnetic field of an induction heating coil. A method of heat sealing tubular plastic members is also disclosed.

Abstract: A multiple part assembly includes an enclosure for a moist pad member. The assembly included a cup-shaped container within which the pad member is located. A heat seal secures the outer edge of the pad member to the container. A support is secured encircling the container and includes an annular backing member encircling the open end thereof. The backing member is adhesively affixed and peelable for the support. A plastic film cover overlies the pad member and adjacent portion of the backing member. An encircling fusion seal joining the plastic film cover to the backing member for removal of the cover with the backing member. A plastic heating tool includes an annular or circular tool element formed of appropriate material which is responsive to an inductive field for self-generation of heat within the tool for attaching the pad to the container.

Abstract: A plastic heating tool unit is provided for cutting, sealing and like working of a relatively thin or film-like plastic element. The tool unit may function to sever a plastic element from a web and create firm thermal attachment thereof to another member. The tool unit includes an appropriately shaped annular or circular tool element formed of appropriate material which is responsive to an inductive field for self-generation of heat within the material. An annular radio frequency induction coil unit is coupled to the tool element. A heat transfer member is secured to the tool element and to a forced cooled heat sink which cools the transfer member and thereby the tool element. The transfer member creates a selected retarded cooling rate of the tool element to provide an improved interaction of the tool member and the plastic element and for more effective heating and cooling thereof.

Abstract: A shear-fusion bond method is provided to create a direct fusion joinder or bond over an extended interface between like thermoplastic elastomeric elements of a block copolymer having a rubber-like center or mid-block and styrene end blocks. Such material has a high melt viscosity and does not readily flow. The interface surfaces are coupled to a heat source and heated to a fusion bonding temperature, thereby softening the interface material so that it flows under pressure. The elements, with the surfaces in pressurized engagement, are rotated relative to each other about an axis which is normal to the interface. Rotation is through an angle of at least 10 degrees to subject the softened interface material to a high rate shear force movement substantially in the plane of the interface. This decreases the viscosity and causes the interface material to bondably flow.

Abstract: A film of an oleaginous substance is interposed between the surfaces of plastic elements to be joined by a thermal bond. The heat necessary for bonding is obtained by the incorporation of heat generating particles in the bond region, either in the plastic element or in the film. The particles are indirectly heatable by a high frequency alternating magnetic field or other suitable field. This provides a rapid and efficient heating of the surfaces to the bonding temperature, with the oleaginous substance enhancing the bonding action and the properties of the bond.

Abstract: A technique for bonding plastic materials includes placement of minute particles at the interface, either between the interface surfaces or within one or both of the interface materials. A particle-moving field, such as an alternating magnetic field where magnetic particles are employed, is created across the interface to directly and correspondingly impress the alternating magnetic field on the magnetic particles while the interface is in a generally movable or yielding state. The alternating magnetic field continuously moves the particles and by proper orientation causes them to oscillate, rotate or otherwise move within the fluid interface material to move and intermix the plastic material and thereby produce an improved interface bond between the materials. The magnetic particles may be selected to also respond to a radio-frequency magnetic field to rapidly generate heat and thus simultaneously create the fluid material at the interface with the material agitation.

Abstract: A stratified structure suitable for joining first and second thermally bondable bodies exhibiting bonding incompatibility. The structure includes a first layer having bonding compatibility with a first of the bodies, a second material layer having bonding compatibility with a second of the bodies and a metallic mesh interposed between the first and second layers for providing internal cohesion and integrity to the bonding agent. The metal mesh also provides a means by which the structure may be heated as by exposure to an alternating magnetic field. In bonding the first and second bodies, the composite bonding agent is positioned between the two bodies and exposed to the alternating magnetic field to effect heat seals between the bodies and the agent and thus between the two bodies.

Abstract: A hose includes a hollow plastic core having an indirectly heatable agent bonded to the exterior thereof by a heat seal. A reinforcing net is embedded in the agent and the composite structure covered with a coating.

Abstract: A container article is formed from a stratified material having an inductively heatable layer. A first article part has a thermally joinable region. A second stratified article part, formed by coextrusion, has a layer containing an oxide susceptor. The container parts are assembled and subjected to an alternating magnetic field to heat the susceptor and thermally join the parts.

Abstract: A stratified structure suitable for joining first and second thermally bondable bodies exhibiting bonding incompatibility. The structure includes a first layer having bonding compatibility with a first of the bodies, a second material layer having bonding compatibility with a second of the bodies and a fibrous stratum interposed between the first and second layers for providing internal cohesion and integrity to the bonding agent by a mechanical interlocking action. In bonding the first and second bodies, the composite bonding agent is positioned between the two bodies and a heat seal effected between the bodies and the agent and thus between the two bodies.

Abstract: A hose includes a hollow plastic core having an indirectly heatable agent bonded to the exterior thereof by a heat seal. A reinforcing net is embedded in the agent when heated and the composite structure covered with a coating.

Abstract: An improved method and apparatus for bonding plastic materials includes placement of minute particles at the interface, either between the interface surfaces or within one or both of the interface materials. A particle-moving field, such as an alternating magnetic field where magnetic particles are employed, is created across the interface to directly and correspondingly impress the alternating magnetic field on the magnetic particles while the interface is in a generally movable or yielding state. The magnetic particles, either as a result of premagnetization or in response to the impressed magnetic field, form individual magnets which move to align themselves with the impressed field in accordance with the direction of the relative polarizations.