JPS5926508A - Preparation of spinneret - Google Patents

Abstract

PURPOSE:To obtain a spinneret free from the deformation and wear of mandrel, wherein polymer feed holes with bottoms are bored through a spinneret plate, reinforcing ribs are protruded from their top open ends to the bottoms, and polymer extrusion holes having a ring-shaped form closed partially, avoiding the reinforcing ribs, are bored through the bottom. CONSTITUTION:The polymer feed holes 2 with their bottoms are bored through the spinneret plate 1, the circular reinforcing ribs 9 are protruded from the inner circular faces at the middle height of these polymer feed holes, to the bottoms and the polymer extrusion holes 3 having a C-shaped form avoiding the reinforcing ribs 9, ring-shaped form closed partially, are bored through the bottom of the polymer feed holes 2, so that the spinning holes 4' are formed, to give the desired spinneret 5'. Since the mandrels 7 are firmly supported by the insides of the spinning holes 4' in this hollow filament spinneret 5', they are not deformed at all even if subjected to the high temperature and high pressure during melt spinning, to give a hollow filament having uniform thickness.

Description

[Detailed description of the invention] The present invention relates to a method for manufacturing a spinneret.

Conventionally, in order to manufacture a spinneret, for example, a hollow fiber spinneret, as shown in FIG. As shown in FIG. 1, a C-shaped annular polymer discharge hole 3 with a partially interrupted tab was drilled through the bottom of the introduction hole 2 to form a spinning hole 4.

Immediately after spinning, the molten polymer discharged through the polymer discharge hole 3 of the hollow fiber spinneret 5 produced in this way is formed into a circular hollow fiber with C-shaped cross-sectional edges welded together as shown in FIG. 6, the upper surface of the core metal 7 inside the polymer discharge hole 3 and its connection part 8 are flat, and the width of the connection part 8 is thin and weak, so when it is first used, it will look like the one shown in Fig. 2. Normal hollow fibers 6 can be obtained, but when used for a long period of time, the core bar 7 deforms and sags as shown in Figure 3 due to the high heat of the molten polymer and high spinning pressure, and the thickness increases as shown in Figure 4a. This results in an abnormal hollow fiber 6' that has a difference in the circumferential direction, that is, is misaligned. As the core bar 7 continues to sag, it falls off as shown by the chain line in FIG. 3, and as a result, an abnormal solid thread 6'' as shown in FIG. 4 is obtained.

The present invention has been made to eliminate such drawbacks,
It is an object of the present invention to provide a method for producing a spinneret in which the core bar inside the polymer discharge hole is never deformed or falls off. □ Hereinafter, an embodiment of the method for producing a spinneret according to the present invention will be described with reference to the drawings. As shown in FIG. Arc-shaped reinforcement lip 9 from the inner circumferential surface of the middle and high part to the bottom surface
Then, a C-shaped annular polymer discharge hole 3 with a partially interrupted tab is bored through the bottom of the polymer introduction hole 2, avoiding the reinforcing lip 9, as shown in FIG. and spinning hole 4
′ is formed.

The upper surface shape of the arc-shaped reinforcing lip 9 is square, but in order to reduce the resistance of the molten polymer during spinning,
It is preferable to form it into a mountain shape or an arc shape.

Hollow fiber spinneret 5 obtained by the above manufacturing method of the present invention
' is the core metal 7 inside the polymer discharge hole 3 and the core metal 7
An arc-shaped reinforcing lip 9 is integrally provided on the upper surface of the connecting portion 8 and is connected to the inner peripheral surface of the middle part of the polymer introduction hole 2, and the core bar 7 is firmly held on the inner surface of the spinning hole 4. Even when subjected to the high heat of the molten polymer and high spinning pressure during spinning, the core 7
The core bar 7Fi does not deform at all and does not sag or fall off even after long-term use. Therefore, the molten polymer discharged from the polymer discharge hole 3 has a cross section C immediately after spinning.
Both end edges of the character shape are welded to obtain a normal hollow fiber 6 with the inner and outer circumferences being the same and the thickness in the circumferential direction being uniform, as shown in FIG.

In the manufacturing method of the above embodiment, a hollow fiber spinneret 5' for melt spinning was made, but a hollow fiber spinneret 5'' for wet spinning may also be made as shown in FIGS. 6a and b. In this case. The polymer introduction hole 2' is formed with an inverted trapezoidal trap, and the reinforcing lip 9 of the core bar 7 inside the polymer discharge hole 3 is connected to the polymer introduction hole 2'.
It protrudes from the top opening edge to the bottom surface.

In addition, in the manufacturing method of the present invention, it is possible to easily manufacture a solid spinneret having irregularly shaped polymer discharge holes 10.11 having protruding portions 10a, lla f: on the inner surface as shown in FIGS. 7 and 8. The protruding portions 10a, lla F of the polymer discharge holes 10.11 of the obtained solid spinneret
i. Since the solid spinneret is held by the reinforcing lip as in the previous embodiment, even if this solid spinneret is used for a long period of time, the protruding parts 10a and 11a will not hang down or fall off, and will be normal or deformed. It is possible to obtain a solid yarn of .

According to the method for producing a spinneret of the present invention as described in detail above, the core metal inside the polymer discharge hole never deforms or falls off even after long-term use, and the hollow fibers or irregularly shaped fibers are normal under normal pressure. An excellent effect is that a spinneret capable of spinning yarn can be easily obtained.

[Brief explanation of drawings]

Figure 1 a, b is a longitudinal sectional perspective view of the main parts showing the steps of a conventional manufacturing method for manufacturing a Fi hollow fiber spinneret, Figure 2 is a cross-sectional view of a normal hollow fiber, and Figure 3 is a conventional hollow fiber spinneret. Fig. 4a is a vertical cross-sectional view of the part showing the state in which the core bar inside the polymer discharge hole is deformed and hanging down, and Fig. 4a shows the abnormal hollow fiber spun from the polymer discharge hole in Fig. Figure 5a is a cross-sectional view of an abnormal solid yarn spun by polymer discharge in which the core metal has fallen off as shown by the chain line in Figure 3.
, FIG. 6a is a longitudinal sectional perspective view of a main part showing the steps of an embodiment of the manufacturing method of the present invention for manufacturing a bid hollow fiber spinneret.
b is a longitudinal cross-sectional perspective view of main parts showing steps of another embodiment of the manufacturing method of the present invention for manufacturing a hollow fiber spinneret for multi-type spinning;
8 and 8 are cross-sectional views showing other examples of polymer discharge holes according to the manufacturing method of the present invention. 1...°°・Match plate, 2.2'...Polymer introduction hole, 3...Polymer discharge hole, 4'...
...Spinning hole, 5'. 5''...Hollow fiber spinneret, 6...Circular hollow fiber, 7...Core bar, 8...Connection part, 9...Curve... Reinforcement lip, 10.11...Polymer discharge hole, lOa, lla...Protruding portion (The above related to the present invention) Applicant Tanaka Kikinzoku Kogyo Co., Ltd. Figure 1Q Figure 1b Figure 2 Figure 4 Q Figure 4 Figure 5 Q Figure 5 b 4' Figure 6 Q Figure 6 Figure 7 Figure 8

Claims (1)

[Claims] At the same time, a bottomed polymer introduction hole is bored in the cap plate, and a reinforcing lip is provided protruding from the upper opening edge of the polymer introduction hole or the inner peripheral surface of the middle part to the bottom surface, and the reinforcing lip is attached to the bottom of the polymer introduction hole at the corresponding edge. A method for producing a spinneret, which comprises forming a spinning hole by piercing a partially interrupted annular polymer discharge hole.