JPH04222203A - Spinneret for combined filament yarn having different fineness - Google Patents

Abstract

PURPOSE:To spun combined filament yarn having large yarn denier difference between yarn of large fineness and yarn of small fineness and to readily and stably obtain high-quality products by using spinneret for combined filament yarn having different fineness, comprising the same spinneret plate equipped with plural spinning holes for small fineness and plural spinning holes for large fineness. CONSTITUTION:A molten polymer is fed from feed holes 4 and 7 to delivery holes 3 and 6. Each delivery hole 6 constituting a polymer delivery hole group 5 for yarn of large fineness is closely arranged in a distance to join the delivery polymer flows. The single delivery holes 3 and 6 have the approximately same land length L and delivery hole diameter D. Since pressure loss of the delivery holes is equal, the polymer is uniformly extruded, the delivery polymer from the delivery hole 3 is made into yarn of small fineness by itself, plural yarns from the delivery hole group 5 are joined at the spinneret part or just below the spinneret part into yarn of large fineness.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a spinneret for obtaining mixed fiber yarns of different fineness by melt spinning, and more specifically, the single fiber deniers are different, the thick yarn is a high shrinkage component, and the fine yarn is a low shrinkage component. Melt spinning for obtaining a mixed fiber yarn of different fineness, which is composed of two or more groups of filaments that act as shrinkage components, has a significantly improved degree of mixing of thick yarn and fine yarn, and has a large bulky feel. Regarding a spinneret for use.

0002

[Prior Art] With the diversification, luxury, and individualization of clothing, research has been actively conducted to incorporate the favorable texture of natural fibers into synthetic fibers. It is widely known that woven or knitted fabrics made from mixed yarns of different fineness have moderate elasticity, firmness, soft surface touch, and fullness, and are extremely effective. The mainstream method for obtaining such mixed yarns is to separately spin multifilaments having different single fiber deniers and physical properties, and then interlace them in a drawing process and mix them together. In this method, multifilaments with different single fiber deniers and physical properties are spun separately, so the single fiber denier and physical properties can be changed significantly during spinning, making it possible to obtain woven and knitted fabrics with a wide variety of textures. .

However, because the spinning is carried out separately, the spinning speed is relatively low at most, several hundred m/min, and the fibers are mixed in a drawing and false twisting process, the degree of fiber mixing is not very high. Not only cannot the fiber density be increased, but it is necessary to add interlacing to increase the degree of blending, which has the drawback of extremely high manufacturing costs. Furthermore, in the case of mixed fibers, a plurality of creel stands are required, and the yarn guidance thereof is also complicated, which is not preferable in terms of workability.

[0004] Of course, methods of mixing fibers during spinning have been proposed to overcome the above drawbacks, but most of these methods involve spinning filaments with different filament deniers and physical properties from multiple spinnerets. In this case, there are problems with the equipment such as the complexity of the equipment or the need for two or more polymer melting zones, and furthermore, because the spinning speed is relatively low, a stretching step is additionally required. Therefore, in order to improve this method, a method of melt-spinning mixed fiber yarns of different fineness using the same spinneret is disclosed in JP-A-60-88107 and JP-A-60-8810.
This is disclosed in Publication No. 9, etc.

Furthermore, high speed spinning, for example spinning speed 350
A method for producing mixed fiber yarn with a speed of 0 m/min or more was disclosed in Japanese Patent Application Laid-Open No. 59-946.
This method has been proposed in Publication No. 13, Japanese Unexamined Patent Publication No. 61-47815, etc. In other words, polyester fibers are oriented and crystallized in the high-speed spinning region, but when thick yarns and fine yarns are extruded from the same spinneret and spun at 3500 m/min or more, the fine yarns become more oriented. Since oriented crystallization progresses more than the thick yarn, the fine yarn becomes a low shrinkage component and the thick yarn becomes a high shrinkage component, and this difference is extracted as a shrinkage difference.

However, in this case, there were many problems in yarn spinning. That is, in these methods, components with different single fiber deniers are simultaneously spun from the same die, but as shown in FIGS. By punching holes 1 and 13, thick and thin threads were simultaneously spun. In terms of texture, it is necessary to make the difference in single fiber denier between thick yarn and fine yarn yarn sufficiently large, and if you want to obtain synthetic fibers that look like natural fibers, the fineness ratio needs to be 8 or more. be. To achieve this, it is necessary to increase the difference in the discharge amount, but the larger the difference, the more difficult it is to obtain a uniform thick denier yarn, the greater the denier unevenness and distribution unevenness, and the unstable the discharge. There was a problem with becoming.

[0007] This is presumed to be due to the following reasons. In other words, in order to maintain the draft at an appropriate value (500 or less at most) in order to obtain spinning stability for thick yarn and fine yarn, the diameter of each discharge hole must be set to the size used for normal yarn spinning. I don't get it. On the other hand, if you try to maintain the fineness ratio, that is, the ratio of the discharge amount per discharge hole to 8 or more, and equalize the pressure loss at the discharge holes of thick and fine yarns, The land length must be several hundred times or more than that used for normal yarn spinning, or the land length of fine yarn must be several hundred times or less than that used for ordinary yarn spinning, which poses practical and processing problems. .

[0008] Therefore, in practice, the land length of the fine yarn yarn, which is difficult to spin, is maintained within the range used for normal yarn spinning, and the land length of the thick yarn yarn is much shorter than the required land length. The pressure loss at the discharge hole for the two types is different, and the pressure loss at the discharge hole for thick yarn is quite low, and is easily affected by variations in temperature, viscosity, kneading, and distribution of the molten polymer, is considered to be unstable.

In order to stabilize the discharge, it is necessary to reduce the difference in single fiber denier between the thick yarn and the fine yarn, and the fineness ratio can only be about 5 at most. Woven and knitted fabrics obtained from mixed fiber yarns lacked firmness and stiffness and had poor texture, which was far from the texture of natural fibers.

0010

Problems to be Solved by the Invention The present invention solves the drawbacks of the prior art as described above, and aims to produce mixed yarns of different finenesses in which the single fiber denier difference between thick yarns and fine yarns is large. The object of the present invention is to provide a spinneret for yarns having different finenesses, which can stably produce yarn using a single spinneret.

[0011]

[Means for Solving the Problem] As a result of intensive studies to achieve the above object, the present inventors have found that the above problem can be solved in melt spinning of polyamide, polyester, etc. by using a specific spinneret as described below. The present invention was completed based on the discovery that the present invention is possible. That is, the present invention provides a spinneret for mixed yarn of different fineness in which a plurality of discharge holes for fineness and a plurality of discharge holes for thickness are arranged on the same spinneret plate, in which the discharge hole for thick fineness is the discharge hole for fineness. and a group of discharge holes having the same pore diameter and land length arranged close to each other within a distance where the discharged polymer flow from adjacent discharge holes merges with each other. This is a spinneret for mixed yarn.

The present invention will be explained below with reference to the drawings. FIG. 1 is a plan view showing the arrangement of the discharge holes of a spinneret as a specific example of the present invention, and FIG. 2 is a longitudinal cross-sectional view of the discharge holes in section A of FIG.

In the figure, 1 is a spinneret plate in which a discharge hole 2 is bored, and the discharge hole 2 is a discharge hole 3 for fine yarn.
and a discharge hole 5 for thick yarn. The discharge hole 3 for fine-grained yarns is provided in its upper part following a large-diameter introduction hole 4 for introducing polymer, which is bored from the upper surface of the spinneret plate 1 . In addition, the discharge hole 5 for thick yarn consists of a plurality of discharge holes 6 arranged within a distance where the discharged polymers merge, and these plurality of discharge holes 6 form a large-diameter polymer containing the discharge hole group. It is provided following the introduction hole 7 for introduction in the same manner as described above.

Here, the melted and filtered polymer is supplied from the introduction holes 4 and 7 to the respective discharge holes 3 and 6, but in the spinneret of the present invention, the polymer discharge hole group 5 for thick yarn is configured. It is necessary that the individual polymer discharge holes 6 are disposed close to each other within a distance where the polymer flows discharged from adjacent discharge holes merge. The close arrangement means that the polymer flows discharged from the discharge holes may be within a distance where they can be fused together due to the balance effect in a molten state, and the shortest distance between the discharge holes is generally 0.5 to 0.5 of the discharge hole diameter. It should be within twice the range. If this is less than 0.5 times, the structure of the die becomes weak and deformation of the die is likely to occur at the group of polymer discharge holes for thick yarn. On the other hand, if the distance is more than twice that, the fusion of the polymer streams becomes unstable, which is not preferable.

Furthermore, in order to stabilize the merging and fusing of the thick yarns and to form a uniform round cross section, holes are formed in a circle circumscribing the group of polymer discharge holes 5 for thick yarns, as shown in FIGS. 3 and 4. It is desirable that these discharge holes 6 are bored in the sagging recess 8. Further, it is preferable that the discharge holes constituting the discharge hole group are arranged rotationally symmetrically and line symmetrically as shown in FIG. 5 or 6.

It is preferable to drill the discharge holes for thick yarns on the upstream side of the cooling wind from the viewpoint of cooling and spinning tension, but in this case, the discharge holes should also be opened to avoid large unevenness in the distribution of the polymer throughout the spinneret. You need to set the interval.

Next, it is necessary that each single discharge hole 3, 6 has substantially the same land length L and discharge hole diameter D. This is to equalize the pressure loss in all the discharge holes, thereby making it unaffected by variations in temperature, viscosity, kneading, and distribution of the molten polymer, and eliminating uneven discharge between the discharge holes. That is, in the present invention, the polymer flow, which is uniformly discharged because the pressure drop of the discharge hole is equal, is spun individually into a fine yarn, and a plurality of polymers are combined at or directly below the mouthpiece and spun to form a thick yarn. This is a spinneret for mixed fiber yarns of different fineness, which can be made into strips.

[0018]

[Examples] The present invention will be explained in more detail below with reference to Examples.

Example 1 Polyethylene terephthalate having an intrinsic viscosity of 0.64 was melted and extruded as a polymer using a die for mixed fiber yarns of different fineness as shown in FIGS. 1 and 2. A total of 80 holes were drilled in the spinneret, and the discharge hole diameter and land length of the discharge holes were all equal, and the discharge hole diameter was 0.15 mm and the land length was 0.50 mm. The discharge holes for thick yarn were composed of eight discharge holes, and were arranged as shown in FIG.

40 fineness yarns discharged from the spinneret,
A yarn consisting of five filaments of thick yarn is cooled and solidified in a 100 cm long cross-blown spinning tube installed 20 cm below the spinneret surface, and after applying an oil agent, it is taken off at 4000 m/min without being wound up. Subsequently, it was drawn to obtain a mixed fiber yarn of different fineness of 80 denier/45 filaments. Fineness yarn 0
．． The yarn was 9 denier, and the thick yarn was 8.8 denier.

At this time, when the cross-sectional area of the thick yarn was measured in 20 cross-sectional photographs of the mixed yarn of different fineness, the variation rate (
100 x standard deviation/average value) is 3.2%, which is good.
The spinning properties were also stable.

Example 2 Polyethylene terephthalate having an intrinsic viscosity of 0.64 was melted and extruded as a polymer using a spinneret for mixed yarns of different fineness as shown in FIGS. A total of 90 holes were drilled in the spinneret, and the discharge hole diameter and land length of the discharge holes were all equal, and the discharge hole diameter was 0.15 mm and the land length was 0.50 mm. The discharge holes for thick yarn were composed of nine discharge holes, and were arranged as shown in FIG.

40 fineness yarns discharged from the spinneret,
A yarn consisting of five filaments of thick yarn is cooled and solidified in a 100 cm long cross-blown spinning tube installed 20 cm below the spinneret surface, and after applying an oil agent, it is taken off at 3500 m/min.
The yarn was then drawn without being wound up to obtain a 100 denier/45 filament yarn with different fineness. Fine yarn 1
．． The yarn was 0 denier, and the thick yarn was 12 denier.

At this time, when the cross-sectional area of the thick yarn was measured in 20 cross-sectional photographs of the mixed yarn of different fineness, the variation rate (
100 x standard deviation/average value) is 4.2%, which is good.
The spinning properties were also stable.

Comparative Example 1 Polyethylene terephthalate having an intrinsic viscosity of 0.64 was melted and extruded as a polymer using a conventional spinneret for mixed yarns of different fineness as shown in FIGS. A total of 45 spinnerets
The discharge hole for thick yarn has a diameter of 0.25 mm and a land length of 0.50 mm, and the discharge hole for fine yarn has a diameter of 0.15 mm and a land length of 0.50 mm.
It was warm in mm.

40 fine yarns discharged from the spinneret,
A yarn consisting of five filaments of thick yarn is cooled and solidified in a 100 cm long cross-blown spinning tube installed 20 cm below the spinneret surface, and after applying an oil agent, it is taken off at 4000 m/min without being wound up. Subsequently, it was drawn to obtain a mixed fiber yarn of different fineness of 80 denier/45 filaments. Fineness yarn 0
．． The yarn was 9 denier, and the thick yarn was 9 denier.

At this time, when the cross-sectional area of the thick yarn was measured in 20 cross-sectional photographs of the mixed yarn of different fineness, the variation rate (
100×standard deviation/average value) had a large variation of 10.5%, and the breakage of the thick yarn under the spinneret occurred 5 times/day, making the spinning property unstable.

[0028]

Effects of the Invention As explained above, according to the present invention, it is possible to easily and stably produce mixed yarns of different finenesses with a large difference in single fiber denier between thick yarns and fine yarns using a single spinneret. It has the remarkable effect of making it possible to obtain a natural fiber-like woven or knitted fabric with excellent elasticity and elasticity.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing the arrangement of discharge holes of a spinneret that is a specific example of the present invention.

FIG. 2 is a longitudinal cross-sectional view of a discharge hole in part A of FIG. 1;

FIG. 3 is a plan view of the arrangement of discharge holes in a spinneret showing another specific example.

FIG. 4 is a longitudinal cross-sectional view of the discharge hole in part A of FIG. 3;

FIG. 5 is a plan view of the arrangement of discharge holes for thick yarn.

FIG. 6 is a plan view showing the arrangement of discharge holes for thick yarns, showing another specific example.

FIG. 7 is a plan view of a discharge hole arrangement showing a conventional spinneret.

8 is a longitudinal cross-sectional view of the discharge hole in part A of FIG. 7. FIG.

[Explanation of symbols]

1 Spinneret plate 3 Discharge hole for fine yarn 4 Polymer introduction hole 5 Discharge hole for thick yarn 7 Polymer introduction hole

Claims (2)

[Claims] Claim 1: In a spinneret for mixed yarn of different fineness, in which a plurality of discharge holes for fineness and a plurality of discharge holes for thickness are arranged on the same spinneret plate, the discharge hole for thick fineness is the discharge hole for fineness. and a group of discharge holes having the same pore diameter and land length arranged close to each other within a distance where the discharged polymer flow from adjacent discharge holes merges with each other. Spinneret for mixed yarn. 2. The spinneret for mixed fiber yarns of different finenesses according to claim 1, characterized in that the discharge holes for large finenesses are formed in recesses bored in a circular shape circumscribing the discharge hole group constituting the discharge holes. .