Patent GB-1048370-A (GB)
Title: Composite filaments and the manufacture thereof
IPC: D01F8/04
Filed: 1965-09-23
Abstract: 1,048,370. Spinnerets. KANEGAFUCHI BOSEKI KABUSHIKI KAISHA. Sept. 23, 1965 [Sept. 26, 1964; Jan. 29, 1965], No. 40636/65. Heading B5B. A composite filament comprises two conjugate thermoplastic, fibre forming polymeric constituents of poor co-adhesive properties extending side by side along the entire length of a single filament, a part of each of the two constituents constituting a part of the external periphery of the filament, and the conjugate abutment line of the two constituents in an arbitrary cross-section of the filament presenting a pattern such that one of the constituents intrudes into the other thereby forming at least one necking. The two constituents may be, e.g. polyamide and polyester, polyolefin and polyamide, or polyolefin and polyester. Other suitable materials include polysulphonamides, polyurethanes, polyureas, polyvinyl chlorides, polyvinylidine chlorides and polyvinyl alcohols. Examples describe the spinning of conjugate filaments of (1) polyhexamethylene adipamide and polyethylene terephthalate; (2) polycaproamide and polyethylene, and (3) polyhexamethylene adipamide and polyethylene terephthalate, and (4) polyhexamethylene sebacamide and polyethylene terephthalate. The conjugate plane of the two constituents forming the filament may be partially separated. A spinneret, as shown, comprises a partition wall 7 for separating two molten spinning materials A and B from each other and a conducting groove 9 for enabling the separated spinning materials to join together so as to form a side-by-side pattern and for conducting them to the rear face of the spinning orifice 8, in which at least one bore or conduit respectively extends through or projects from the partition wall so as to allow one material to extend into the other. In Fig. 2, a bore 9 extends through the partition wall with an inlet on one face of the partition wall and an outlet on the other face. In Fig. 3 (not reproduced) the bore or conduit is disposed parallel with one face of the wall along the direction of flow. In a further form (Fig. 4, not shown), the partition wall is provided with a projecting conduit which is slotted to allow the entry of one flow of material, and is arranged to supply the material entering the conduit to a location on the conjugate plane between the two materials. Fig. 7 (not shown), illustrates a projecting conduit. In Fig. 1 (not shown), constituent A is supplied from supply chamber 1 through conduit pipe 2 to annular groove 3, and constituent B is supplied from chamber 4 through conduit pipe 5, to annular groove 6. Constituents A and B flow downwards from annular grooves 3 and 6 along partition wall 7, are conjugated together at the outer end of the partition wall; and extruded under pressures through spinning orifices 8. Thus, a composite filament having two polymeric constituents in side-by-side relationship is formed. Using a spinneret in which the cross-section of the bore 9 is circular, as shown in Fig. 5, (not reproduced), and spinning orifices which are circular a composite filament having a protruding pattern, as shown in Fig. 8, is obtained. Where two bores are provided through the partition wall in parallel relationship with each other, the resulting composite filament is as shown in Fig. 9 (not shown). The filament of Fig. 10 (not shown), is made by using two bores in intersecting relationship with respect to the longitudinal cross-section of partition wall 7. If the outlet of bore 9 is arranged to project into the path of constituent B, or if the extrusion pressure of constituent A is greater than that of constituent B, the resulting filament is as shown in Fig. 11 (not shown). Other forms of filament are shown in Figs. 12 to 16 (not shown). The filaments of Figs. 17 and 18 are obtained by using spinning orifices of triangular cross-section.