JP2010018914A - Spinneret for conjugate spinning and method for producing conjugate fiber using the spinneret unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spinneret unit of simple structure for a side-by-side conjugate fiber, with no need of any complicated spinneret unit pack, enabling a constitutive filament number and component ratio to be changed easily, also giving a stable conjugate liquid flow and uniformizing conjugate fiber's conjugate form and conjugate ratio, and to provide a method for producing the conjugate fiber. <P>SOLUTION: The spinneret unit 11 for making a conjugate spinning for a side-by-side conjugate fiber is provided which is intended for spinning two kinds of spinning dope with low compatibility with each other in the form of a concentric conjugate liquid flow. In this spinneret unit, a plurality of nozzles 12 are arranged on a single circumference at equal intervals and also on the boundary line between two components 18 and 19 of the concentric conjugate liquid flow, wherein each of the nozzles 12 includes a dope inlet 13 of nearly inversely truncatedly conical shape to introduce the conjugate liquid flow thereinto, a columnar extrusion portion 15, and a junction joining the dope inlet 13 and the extrusion portion 15 each other and having a surface curved in the direction of extrusion, and, preferably, the introduction angle of the dope inlet 13 is smaller than 60°. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a composite spinneret device used for manufacturing a composite fiber composed of two different types of polymers and a method for producing a bonded composite fiber using the composite spinneret device.

Many apparatuses for producing composite fibers have been proposed. For example, according to Japanese Patent Application Laid-Open No. 2000-248421 (Patent Document 1), two or more spinning stock solutions are fed into individual spinneret packs through individual liquid feeding lines, and the spinning stock solution is placed just before each die device hole. A composite fiber having a core-sheath structure is produced by discharging the composite. Further, for example, in Japanese Patent Application Laid-Open No. 2002-173821 (Patent Document 2) and Japanese Patent Application Laid-Open No. 2006-138048 (Patent Document 3), a composite liquid flow combined concentrically is formed in a circular groove formed on a concentric circle. A side-by-side bonded composite fiber is produced by discharging from a spinning spinneret device having a plurality of discharge holes arranged along the side.
JP 2000-248421 A Japanese Patent Laid-Open No. 2002-173821 JP 2006-138048 A

  By the way, in the spinning device disclosed in Patent Document 1, a base plate is closely stacked in three stages from the bottom inside the cylindrical pack body shell, and a central filtration part and an annular filtration part are concentrically arranged thereon. A bottomed filtration member having From the bottom of the bottomed filtration member, a lower polymer dispersion plate, a lower filter, and a filtration sand portion are sequentially laminated. Further, a top insert, a hollow lock ring, and a wear plate are sequentially stacked on the filtration sand portion, and a seal member is brought into close contact with the disc-like space formed between the top insert, the hollow lock ring, and the wear plate. It is intervened. Moreover, each laminated member is formed with different polymer distribution holes and grooves.

  As described above, the spinning device disclosed in Patent Document 1 requires a spinneret device pack that is extremely complicated and requires extremely high processing accuracy for each component member, and the number of filaments and the component ratio can be easily set. Although it can be changed, the composite liquid flow becomes unstable depending on the type of the spinneret used and the combination of the spinning stock solutions, and the composite form and composite ratio of the composite fibers formed from the respective discharge holes are not stable. May be uniform.

  On the other hand, according to the manufacturing method of the side-by-side bonded composite fiber disclosed in Patent Documents 2 and 3, a plurality of simple cylindrical discharge holes are arranged at a predetermined pitch along the circular concave groove. Yes. That is, two or more kinds of composite spinning liquid streams combined concentrically are supplied to the concave groove, and a spliced composite fiber is spun from each discharge hole. Therefore, the boundary portion of the composite spinning solution is likely to be unstable, and the composite form and the composite ratio of the composite fiber discharged from each discharge hole may become non-uniform, similar to the above-mentioned Patent Document 1, in each discharge hole. There is no guarantee that they will be reliably compounded with the desired compound ratio.

  The present invention has been made to solve these conventional problems, and its specific purpose is simple in structure, does not require a complicated base device pack, and changes in the number of constituent filaments and the ratio of components. It is an object of the present invention to provide a spinneret for a bonded composite spun fiber and a method for producing the same, in which the composite form and the composite ratio can be made uniform since a stable composite liquid flow can be obtained.

  A first basic configuration of the present invention is a splicing device for a composite-spun composite fiber for spinning two types of spinning stock solutions composed of concentric composite liquid streams, wherein a plurality of discharge holes have a single circular shape. It is arranged on the boundary line of the two components of the concentric composite liquid flow at equal intervals on the circumference and calculated from the volume occupancy of the concentric composite liquid flow, and the discharge hole introduces the composite liquid flow A substantially inverted frustoconical stock solution introduction portion, a columnar discharge portion, and a connecting portion having a curved surface that curves in the discharge direction connecting the stock solution introduction portion and the discharge portion. According to a preferred embodiment, the introduction angle of the stock solution introduction part is less than 60 °.

  In addition, the second basic configuration of the present invention is the production of a bonded composite spun fiber in which two kinds of spinning solutions having low compatibility are made into a concentric composite liquid flow and then spun using the above-mentioned composite spinning die apparatus. Is in the way.

  By using the compound spinning device having the above-described configuration, the number of filaments and the component ratio can be easily changed, and a stable composite liquid flow can be obtained. Regardless, the composite form and composite ratio of the composite fiber can be made uniform. When the introduction angle θ of the stock solution introduction part is 60 ° or more, the boundary between the two components is difficult to flow in layers, and the joining flow is likely to be disturbed. In addition, it is desirable that the two types of spinning stock solutions used in the method of the present invention have low compatibility, and if the compatibility is high, the spinning stock solutions are dissolved together before being discharged from the composite spinning die apparatus, and high quality It is difficult to obtain bonded composite fibers. Furthermore, it is preferable that the viscosity of the spinning dope disposed outside the composite liquid flow is lower than the viscosity of the spinning dope disposed inside. By increasing the viscosity of the inner spinning dope, the composite ratio can be made more uniform.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of a composite spinning die apparatus according to the present invention will be specifically described with reference to the drawings.
FIG. 1 is a plan view of a spinneret device pack used in the compound spinning device of the present invention as seen from the composite liquid flow introduction portion side.

  Each discharge hole 12 needs to be arranged at equal intervals on the same circumference. When the arrangement of the discharge holes 12 is not on one circumference or when the hole intervals are unevenly arranged, the ratio of each spinning dope is not equal in all the discharge holes 12, and the composite ratio in each single fiber And the composite form becomes difficult to be uniform.

  In addition, in order to obtain a composite fiber having a uniform composite ratio and composite form, it is necessary that the center O ″ of the composite spinneret device 11 and the center of the composite liquid flow are aligned with each other. By making the center O ″ of the composite spinneret device 11 coincide with the center of the composite liquid flow, the composite liquid flow is easily distributed uniformly to all the discharge holes 12, 12,.

  Furthermore, in order to obtain a composite fiber having a uniform composite ratio, it is formed through a circle formed by the boundary line of the occupied area of the outer layer component 18 and the inner layer component 19 forming a concentric circle and the center of each discharge hole 12. The circular shape must be on the same circumference. Since the two circles are concentric, the composite liquid flow is easily distributed uniformly to all the discharge holes 12, 12,. When you want to change the composite ratio, change the composite ratio of the concentric composite liquid flow and change the diameter of the boundary line between the two types of composite liquid flow in response to the change in the composite ratio. 11 is used.

The diameter of the boundary line between the two types of composite liquid flows can be obtained by the following calculation formula.
Formula 1:
Boundary line diameter (mm) = 2 × ((S × A / (A + B) / Π)) ^0.5
However, S: area of the cap-like circular mouth bottoms (mm ^2), A: volume discharge rate of the inner layer component ^{(mm 3 / min), B} : volume discharge rate of the outer layer components (mm ³ / min)

  FIG. 2 is an enlarged plan view of the discharge hole as seen from the side where the spinning solution is introduced, FIG. 3 is a partial cross-sectional view of the base device, and FIG. 4 is an overall cross-sectional view of the base device. As shown in FIG. 4, the composite spinning die apparatus 11 according to the present invention has a cap-like shape as a whole and has a cap-like shape, and is used by inverting it vertically. As shown in FIG. 3, the discharge hole 12 of the compound spinning device 11 is located at the bottom of the main body 17 of the compound spinning device 11 and has a predetermined distance CP on the same circumference having a desired diameter. (See FIG. 2).

  The discharge hole 12 includes a spinning stock solution introduction portion 13 having a roughly inverted frustoconical shape from the spinning stock introduction side, an arc-shaped connection portion 14 connected to a discharge side end of the spinning stock solution introduction portion 13, and the connection And a cylindrical portion 15 connected to the discharge side end portion of the portion 14 and extending to the discharge port. In the present invention, the introduction angle θ of the spinning dope 13 in the discharge hole 12 needs to be less than 60 °. Here, the introduction angle θ of the spinning dope introducing section 13 refers to the introducing angle toward the inlet side of the spinning dope introducing section 13 as shown in FIG. In particular, when the distance CP (mm) between the discharge holes exceeds the diameter D + 1 (mm) of the inlet portion of the spinning dope introducing portion 13, if the introduction angle θ of the spinning dope introducing portion 13 is 60 ° or more, the two-component Since the boundary portion is less likely to flow in a layered manner and the joining flow is disturbed, the composite form of the resulting composite fiber is less likely to be uniform for each single fiber.

  Here, the distance CP between the discharge holes refers to the distance (mm) between the centers O and O ′ of the adjacent discharge holes 12 and 12 as shown in FIG. As shown in FIG. 2, the diameter D is an inlet diameter (mm) of the spinning dope introducing unit 13 in the center line direction of the base device 11.

On the other hand, the smaller the introduction angle θ of the spinning dope 13 is, the more difficult it is to manufacture the die apparatus.
The shape of the connecting portion 14 is preferably a slope having a constant rate acceleration curve shape in which the acceleration rate per movement of the spinning dope is constant.

  It is desirable that the two types of spinning dope used in the present invention have low compatibility. If the compatibility is high, the spinning dope solutions are dissolved together before being discharged from the spinneret device 11, and it becomes difficult to obtain a composite fiber. Further, it is desirable that the viscosity of the spinning dope used in the present invention is lower than that of the spinning dope disposed on the inside of the spinning dope disposed on the outside of the composite liquid flow. By increasing the viscosity of the inner spinning dope, the composite ratio can be made more uniform.

  The composite spinneret device 11 of the present invention can be applied to any of dry spinning, wet spinning, and melt spinning. In dry spinning, the degree of substitution of cellulose acetate, the degree of polymerization, or components with different additives can be combined. In wet spinning, it is suitable for compounding acrylic copolymer components and components having different polymerization degrees, and for melt spinning, it is suitable for compounding polyester copolymer components, polymerization components and components having different additives.

Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples.
Table 1 shows the evaluation results of the cross-sectional stability in Examples 1 and 2 and Comparative Examples 1 to 6. The cross section of the obtained fiber bundle was observed with an optical microscope, and the presence or absence of a composite fiber different from a predetermined ratio and a single fiber whose shape was broken was evaluated.

Example 1
As a spinning dope, cellulose diacetate having an average substitution degree of 2.41 was dissolved in a mixed solvent of 91% by weight of methylene chloride / 9% by weight of methanol, and a stock solution of cellulose diacetate having a concentration of 22.1% by weight and a viscosity of 850 poise at 25 ° C. A cellulose triacetate with an average substitution degree of 2.91 was dissolved in a mixed solvent of 91% by weight of methylene chloride / 9% by weight of methanol to prepare a cellulose triacetate stock solution having a concentration of 21.9% by weight and a viscosity of 1100 poise at 25 ° C. did.

This spinning stock solution is weighed with an individual metering pump so that the solid content ratio is 50:50, and a two-layer concentric composite solution in which the inner layer is a cellulose triacetate stock solution and the outer layer is a cellulose diacetate stock solution. A flow was formed. This concentric composite liquid flow is fed to the spinneret of the present invention by a cylindrical pipe having a length of 1 m, and 70 ° C. by hot water flowing through a preheater arranged outside the cylindrical pipe during the feeding. Heated. At this time, the volume discharge amount of the inner layer component was 4380 (mm ³ / min), and the volume discharge amount of the outer layer component was 4380 (mm ³ / min).

  As the spinneret apparatus, 16 discharge holes with a diameter of 32 μm are arranged at equal intervals on the same circumference with a diameter of 16.5 mm in a cap-shaped circular mouthpiece apparatus with an inner diameter of 23.4 mm, an introduction angle of 45 °, CP Was spun at a spinning speed of 600 m / min by a dry spinning method using a spinneret apparatus having the shape shown in FIGS. 1 to 3 having a diameter of 3.24 mm and a diameter D of 0.81 mm.

  The obtained fiber was 40 dtex, 16 filaments (hereinafter referred to as “f”), and the cellulose triacetate component and the cellulose diacetate component were uniformly bonded side by side at a weight ratio of 50:50.

(Example 2)
Spinning was performed in the same manner as in Example 1 except that a spinneret apparatus having 30 discharge holes was used and the discharge amount was changed. The obtained fiber was 84 dtex / 30f, and the cellulose triacetate component and the cellulose diacetate component were uniformly bonded side by side at a weight ratio of 50:50.

(Comparative Examples 1-6)
Fibers obtained by spinning in the same manner as in Example 1 with the composite ratio, the diameter of the circle (PCD) in which the discharge holes are arranged, and the introduction angle shown in Table 1 are 40 dtex / 16f and 80 dtex / 30f. The cellulose triacetate component and the cellulose diacetate component were bonded in a side-by-side manner, but contained single fibers having a non-uniform composite ratio.

It is the top view which looked at the nozzle | cap | die apparatus for composite spinning of this invention from the introduction part side. It is a partial top view which expands and shows the discharge hole of the nozzle | cap | die apparatus for composite spinning. It is a fragmentary sectional view of the die apparatus for compound spinning of the present invention. 1 is an overall cross-sectional view of a composite spinning die apparatus of the present invention.

Explanation of symbols

11 Spinneret device
12 Discharge hole
13 Spinning solution introduction part (straight slope)
14 Connecting part
15 Cylinder
16 Buttocks
17 Body
18 Outer layer component of spinning dope
19 Inner layer component of spinning dope θ Introduction angle
CP Distance between adjacent discharge holes
D Entrance diameter of spinning dope
Diameter of the circle formed by the PCD discharge hole

Claims (3)

A spinneret for composite spinning of bonded type composite fibers for spinning two types of spinning stock solutions composed of concentric composite liquid streams,
A plurality of discharge holes are arranged at equal intervals on one circumference and on the boundary line between the two components of the concentric composite liquid flow calculated from the volume occupancy of the concentric composite liquid flow,
The discharge hole has a substantially inverted frustoconical stock solution introduction part for introducing the composite liquid flow, a columnar discharge part, and a curved surface curved in a discharge direction connecting the stock solution introduction part and the discharge part. A connecting portion having
The introduction angle of the stock solution introduction part is less than 60 °,
A base device for composite spinning of bonded composite fibers.   A method for producing a bonded composite spun fiber in which two types of spinning solutions having low compatibility are made into a concentric composite liquid flow and then spun using the base device for composite spinning according to claim 1.   The method for producing a bonded composite spun fiber according to claim 2, wherein the viscosity of the spinning dope disposed outside the composite liquid flow is lower than the viscosity of the spinning dope disposed inside.

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