GB1289387A - - Google Patents

Abstract

1289387 Bookbinding M S SENDOR and B T SENDOR 13 Feb 1970 [14 Feb 1969] 6976/70 Heading B6A Paper sheets or signatures which are to be bound together are treated uniformly over their entire area with a thermoplastic resin composition e.g. polyethylene resin, incorporated with the fibre assembled, and then subjected to heat and pressure which binds them together. In one arrangement, Fig. 6, leaves 24 are welded along a fold line 26 by means of heated clamping jaws 28, 30. The lower jaw 28 may be part of a conveyer system bringing successive signatures to a welding station and the upper jaw may comprise a roller. According to Fig. 7, signatures 40, 42 the separate leaves of each of which may have been welded as shown in Fig. 6, are clamped by heated jaws 48, 50 at the areas to be welded and by additional jaws outside that area. Dielectric heating may, however, be applied from an electrode assembly 51. Infra-red heating may be employed (Fig. 13). In another arrangement (Figs. 9, 10), the edges of an assembly of sheets to be bound are subjected to the action of a pair of jaws vibrated towards and away from one another at a supersonic frequency. The action of the jaws may generate heat in the sheets to cause the welding but auxiliary heating may be employed. The jaws may have spaced projections engaging the sheet assembly so that the welding is intermittent.