Patent GB-1107117-A (GB)
Title: Method and apparatus for spinning multi-component fibres
IPC: D01D5/32
Filed: 1965-06-15
Abstract: 1,107,117. Spinnerets. JAPAN EXLAN CO. Ltd. 15 June, 1965 [15 June, 1964], No. 25340/65. Heading B5B. In a method of spinning multi-component fibres from at least two different fibre forming spinning solutions by extruding them concurrently through a common orifice, before being extruded through the orifice, these spinning solutions are maintained at a temperature in the range of 70 to 90 C. and interfacially contacted for a period of time of at least 0À1 second and sufficient for there to be formed, between the spinning solutions, an intermediate area wherein the spinning solutions are sufficiently intermingled or diffused with each other to unite the different components in the resulting fibres firmly prior to extrusion of the solutions through the orifice. The contacting time is desirably at least 0-2 seconds. The apparatus of Fig. 1, comprises a plurality of partition walls 1, defining narrow longitudinal channels 2 within a cylindrical sleeve 3. The lower end portion of each partition wall is tapered to have a V-sectioned edge as shown. The inlet section of cylindrical sleeve 3 is fitted with a baffle 4 which divides the inlet section into two chambers 5 and 6, which receive the different spinning solutions. The arrangement is such that alternate channels 2 receive different spinning solutions. In association with the lower end of sleeve 3 there is fitted a circular guide plate 7 which has a corresponding number of V-sectioned grooves 8. When assembled, each V-sectioned edge of partition wall 1 extends in the thickness direction of plate 7 into the upper groove-like part of the corresponding groove 8 and defines the two upper limbs of a Y-sectioned channel having a lower, vertical channel stem portion 9, if the assembly of the sleeve 3 and plate 7 is regarded in longitudinal section on the plate 7 defining a V-shaped channel merging into a straight channel portion 9 of the Y-shaped channel 8. The channel portion 9 communicates with the corresponding orifices 10 of spinneret 11, which is held in a cap assembly 12. In operation, two different spinning solutions are supplied to the chambers 5 and 6 respectively and then forced into the channels 2 through which the solutions flow downwardly. At the top of the respective V-channels defined by the V-sectioned edge and the respective grooves 8 the two different solutions mingle and flow together into the respective channel portions 9 in lamina flow with the adjacent faces of thin films of the different solutions in inter-facial contact. The solutions are then continuously and concurrently extruded through the respective orifices 10 into a conventional coagulating bath (not shown) wherein conjugate fibres are formed. The channel portions 9 are made long enough to allow interfacial contact for at least 0À1 second between the different solutions during their passage therethrough prior to their extrusion through the orifices 10. If desired as in the case where the flow rate of the spinning solutions is high, an intermediate guide disc 13 having a plurality of narrow channels 13, corresponding to and communicating at the upper end with the respective channel portions 9 and at the lower end with the corresponding orifices 10 is arranged to obtain a length of the channels 9 and 14 necessary for producing the required intermingling for mutual diffusion of the solutions. The intermediate guide disc 13 may be made of plastic or rubber material resistant to heat and chemicals. Examples describe the wet spinning of an acrylonitrile-methyl acrylate co-polymer to form conjugate filaments.