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: An improved process of attaching a book body to a case at the hinge to form a hard bound book. A liquid thermoplastic bonding agent is applied to the body or case at the hinge area. The bonding agent is allowed to dry and form a solidified layer. The body is then inserted into the case so that the portion to which the agent has been applied is located at the hinge of the completed book. The dried bonding agent is heatable upon exposure to an alternating electric field and melts to form the attachment at the hinge area. Pressure applied to the hinge area assists in forming the attachment and reduces the thickness and heat generation of the layer.

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 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.