Abstract: A method of welding at least two layers of a thermoplastic film which comprises a copolymer or copolymer-polymer mixture selected from the group consisting of ethylenevinylacetate (EVA) copolymer, an EVA copolymer and polyethylene, an EVA copolymer and polypropylene, and an EVA copolymer and polyethylene and polypropylene, with the proviso that the concentration of vinylacetate in said film is from about 12 to about 28% by weight, said method comprising the steps of:pressing said at least two layers of said thermoplastic film;applying a high frequency current to said pressed layers in order to weld said layers together; andrecovering said welded layers.

Abstract: An improved slide mount of the type comprising a flat rectangular pocket forming a slideway for receiving a standard slide film provided with two lateral rows of driving notches, a central window formed in the pocket and a deformable slot in communication with the slideway to allow the introduction of the slide film with its rows of notches perpendicular to the slot into the slideway. This slide mount is improved in that at least one sprocket is provided for inside the slideway so as to engage one of the notches of the film and lock the same inside the slideway. This sprocket is smaller in size than the notch it engages to let the film free to expand to a certain extent when subjected to the heat of a lamp.

Abstract: An album leaf and method of making it is disclosed. The leaf has a peripheral frame of metal or other suitable material which includes a bead and inwardly extending skirts for holding a base sheet therebetween. Adhesive means on the surface of the skirt retain a mat thereon, securing a photograph beneath the mat. A hinge segment is attached to the binding edge of the leaf.

Abstract: A method of welding at least two layers of a thermoplastic film which comprises a copolymer or copolymer-polymer mixture selected from the group consisting of ethylenevinylacetate (EVA) copolymer, an EVA copolymer and polyethylene, an EVA copolymer and polypropylene, and an EVA copolymer and polyethylene and polypropylene, with the proviso that the concentration of vinylacetate in said film is from about 12 to about 28% by weight, said method comprising the steps of:pressing said at least two layers of said thermoplastic film;applying a high frequency current to said pressed layers in order to weld said layers together; andrecovering said welded layers.