| 摘要 |
1,269,066. Laminating; seaming non-metallic sheet material. ALGEMENE KUNSTZIJDE UNIE N.V. 28 March, 1969 [2 April, 1968], No. 16519/69. Headings B5K and B5N. A method of sealing together at least two films by the application of heat and pressure, which films each comprise two or more layers of alternately different thermoplastic polymers having different softening points, said method comprising pressing the films together, heating in a first stage to a temperature of at least the softening point of the lowest-melting thermoplastic but below the softening point of the highest-melting thermoplastic and heating the surfaces in contact in a second stage to at least the softening point of the highest-melting thermoplastic so that one or more layers of the lowest-melting thermoplastic are at least partially displaced and two or more layers of the highest-melting thermoplastic are sealed together. The example describes the sealing together of films 1 and 2 each consisting of 8 alternate layers of polyethylene 6 and a polyamide 7 between jaws 3 and 4 which may be heated by high-frequency heating, impulse heating, contact heating or supersonic heating. |
