Patent GB-1192270-A (GB)
Title: Mix-Spinning Apparatus.
IPC: B01F5/06
Filed: 1968-12-20
Abstract: 1,192,270. Mix-spinning apparatus. KANEGAFUCHI BOSEKI K.K. 20 Dec., 1968 [20 Dec., 1967; 27 Feb., 1968], No. 60808/68. Heading B5B. A mixer for stratifying at least two different spinning materials into multi-layers comprises a three-dimensional passage network comprising at least two network elements in successive stages, the outlet portion of the network element in each stage being connected to the inlet portion of the network element in the succeeding stage, each network element comprising at least one unit passage comprising a main passage having at least one branch passage, which is substantially coplanar therewith, at least one inlet and at least one outlet arranged substantially perpendicularly to the plane of the main and branch passages, the inlet(s) and outlet(s) being arranged alternately along the main passage and the inlet(s) and outlet(s) being provided in said branch passage or said main passage. The mixer suitably takes the form of a spinneret, useful in making multilayer filaments, especially uniform mixed filaments, and works by layer-multiplication, as shown in Fig. 7. Two spinning materials A and B are joined at J, to form a component AB, which is separated at S into two components AB and A<SP>1</SP>B<SP>1</SP>, which are later joined at J 2  into a four-layer structure ABA<SP>1</SP>B<SP>1</SP>. In order to effect layer-multiplication, the plane in which the materials are split must be out of phase with, i.e. at an angle to the plane in which they are joined, the most efficient angle being 90 degrees. In general, where n is the number of joining and separating stages, 2<SP>n</SP> layers are theoretically . obtainable, using two spinning materials, and where three spinning materials are used, 3 x 2<SP>n-1</SP> layers. In practice the number of layers obtained is somewhat less. Fig. 3 shows a multilayer filament so made; irregular disturbance of the flow of spinning material in the spinnerets results in a filament having a distorted grainy construction as in Fig. 4. If spinning materials having no affinity for each other are used e.g. polyesters and polyamides, a multi-layer filament of archipelagic construction is obtained, as in Fig. 5, or a filament having a nebularly distributed construction, as in Fig. 6. The network element or unit passage used in the mixer is shown diagrammatically in Fig. 10. Spinning materials supplied to inlet I connected to the branch passage M are separated at S and after passing through the circular main passage I are joined at point J, which coincides with the outlet O. The small black and white circle at inlet I shows the phase or direction in which the spinning materials are joined together. A large number of alternative constructions are illustrated in other Figures, not reproduced. In practice, separation at point S is effected using the device of Fig. 19, and joining at point J using the device of Fig. 24. To increase layer-multiplying efficiency, at least two inlets I and outlets O should be provided as shown in Figs. 31-34 (not reproduced), and for efficient spinning of a uniform mixed filament using a large number of orifices, the number of inlets or outlets of one element should be more than four, and preferably more than eight. This may be achieved by arranging a number of independent elements in parallel, or preferably, by arranging a number of unit passages to form an element, as in Figs. 35-51 (not reproduced), and connecting the elements to form a multi-stage passage network, as in Figs. 58-60 (not reproduced). Fig. 61 shows a spinneret of the invention. Spinning materials from reservoirs 1 and 2 are joined at partition 4, and flow out from inlet holes 11 into passages 12 and 13 in the lower surface of first-stage distributing plate 10, the construction of which is shown in Fig. 62. In these passages the spinning materials are separated and joined, and then flow out through outlet holes 21 which also form the second stage inlet holes. The process is replated in distributing plates 20, 30 and 40 and the multilayered filament is extruded through orifices 105 in spinneret plate 100. Figs. 63-65 (not reproduced) show a distributing plate in which the element is divided into two portions which are arranged in the upper and lower surfaces of the plate, and Figs. 66-69 (not shown), a distributing plate comprising a combination of three plates (10a), (10b) and (10c) Fig. 70 shows a further spinneret, of cylindrical construction. Spinning materials from concentric reservoirs 1 and 2 are joined and separated out of phase at 5 stages, viz., distributing plates 10, 20, 30, 40 and 50 prior to extrusion at spinneret plate 100. The detailed construction of the spinneret is shown in Figs. 71, 72 and 73 (not shown). Fig. 74 (not shown) shows a spinneret similar to that of Fig. 70, but differing in type of element used; this is shown in detail in Figs. 75-77 (not shown). In all the spinnerets, orifices of non-circular cross-section may be used to obtain filaments of non-circular cross-section. Specified spinning materials include polyamides; polyesters; polyethers; polyolefins; polyvinyl chloride; polystyrene; polyvinyl alcohol; polyacrylonitrile; polyureas; polyurethanes and copolymers or modified polymers thereof. Wet-, dry- or meltspinning techniques may be used.