JPS63270806A - Spinning nozzle for acetate yarn - Google Patents

Abstract

PURPOSE:To obtain the titled nozzle for dry spinning of acetate yarn, providing acetate fiber bunch having excellent filtering effect and hardness, comprising nozzle holes of a specific polygonal shape having circumferential length of nozzle hole and nozzle hole area satisfying specific correlation. CONSTITUTION:A nozzle equipped with nozzle holes comprising three or more angular parts theta having <60 deg., having circumferential length of nozzle hole and nozzle hole area satisfying L<2>/(4piS)>1 [L is circumferential length of nozzle hoe (mu); S is nozzle hole area (mu<2>)]. Acetate fibers having high filtration efficiency as cigarette filter and excellent reproducibility of hardness are obtained from acetate yarn spun from nozzle holes of regular triangle. When the value of L<2>/(4piS) exceeds 5.1, end breakage likely occurs.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a spinning nozzle used for dry spinning acetate fibers, and more specifically, under the same amount of fiber used, The present invention relates to a spinning nozzle used for producing acetate fiber aggregates that provide superior filtration effects and hardness, and acetate yarns that are bulky and heat-retaining.

[Conventional technology]

Traditionally, acetate fibers have been produced by dry spinning with circular spinning nozzles.

After that, U.S. Patent No. 2829027, Japanese Patent Publication No. 37-7
As seen in No. 917, acetate fibers with a Y-shaped cross section were manufactured using a triangular spinning nozzle,
It replaces most of the acetate fibers for cigarette filters, and some of it is also commercially available as filament yarn.

[Problems to be Solved by the Invention] In the case of acetate 41 fibers for cigarette filters, by changing from a circular spinning nozzle to a triangular spinning nozzle, it became possible to develop a much higher ventilation resistance with the same amount of fiber. As a result, a higher t hyperactivity rate can be obtained. In order to obtain even better filtration efficiency, it is effective to reduce the spinning nozzle hole area and make each single fiber that makes up the filter thinner. This requires additional technology and also reduces the hardness required for the cigarette filter.

The invention is a dry-spun acetate fiber that provides superior T-strengthening effect and hardness development compared to commonly used triangular-shaped acetate fiber aggregates that are dry-spun using a nozzle. This paper proposes a spinning nozzle for spinning fibers, and at the same time, a spinning nozzle that can produce acetate yarn with excellent bulkiness, heat retention, and lightweight feel.

[Means for Solving the Problems] The present invention provides a nozzle having a polygonal nozzle hole having three or more corners smaller than 60°, which The acetate fiber spinning nozzle is characterized in that the relationship with S) is in the range of 51≧L274π days≧t7.

The commonly used triangular spinning nozzle is
As shown in the figure, it has an equilateral triangular hole shape with an angle θ of 60°, and the length t2 of the negative side is changed depending on the required thickness of the fiber. In this case, the square of the hole circumference is
The value obtained by dividing the hole surface mB by 4g (hereinafter referred to as SF value) is 1.65. The cross-sectional shape of acetate fibers dry-spun from such a spinning nozzle is Y-shaped.
The 8F value of this cross section is 2.0 to 2.0 for yarns of 2 to 4 deniers.
It becomes the value of z7.

It is said that if the thickness of the fibers is the same, increasing the ay value of the cross section of the fiber will increase the ventilation resistance, resulting in acetate fibers with high permeability. Is it necessary to increase the EIF value of the spinning nozzle hole? In fact, those spun through a square nozzle hole with an 8F value or 1.27 are better than those spun through a circular nozzle hole with a value of 81' or 1.27.

It is possible to obtain better airflow resistance by spinning than a nozzle hole having an equilateral triangular shape with EiF (i=1.65).

In order to make the 8PffiTh higher than the equilateral triangular shape, it is possible to make the fiber into a rectangular shape with a ratio of the short side to the long side of more than 2.84. An example is shown. However, the fibers spun from such a rectangular spinning nozzle have a high 8y value but a flat fiber cross section, and even though ventilation resistance can be improved to some extent, the hardness required for cigarette filters cannot be improved. Further improvement is considered necessary.

The Ministry of the Invention has provided Article 10. As shown in Figure 3, the corner θ 6
It was discovered that the 8F value could be increased by making the angle smaller than 0°, and furthermore, as shown in FIGS. 4 and 5, by notching the corner tips, the above-mentioned result could be achieved. It was discovered that a spinning nozzle with a concave curve Ck exceeding 180° and a smoothly connected hole shape tM can produce excellent effects, and the present invention was completed.

The present invention greatly reduces the SF value of the nozzle hole by making three or more corners smaller than 'ff 60', and as a result,
By increasing the 8F value of the fiber cross section, it is possible to produce acetate fibers with high r-perturbation rate and excellent hardness for cigarette filters, and when used as filament yarns, it has bulky properties, heat retention, This allows for acetate fibers with excellent lightweight feel.

In order to spin fibers of the same thickness, it is necessary to use nozzles with the same hole area.As shown in Fig. fA1 and Fig. As the size is increased, fibers with better performance can be obtained than those spun using an equilateral triangular nozzle hole, but when the 8P value exceeds 5.1, the yarn tends to break during spinning. In addition, as shown in Figures 14 and 5, by notching the tip of the corner, more stable spinning becomes possible. If the notch length bl is less than 6μ, it is not very effective, and if it exceeds 12μ, the SF value of the fiber cross section after spinning becomes small.

Furthermore, the same effect can be obtained by connecting the corners C with a diameter exceeding 180° as shown in FIG. 6 as a result of reducing the tip angle.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 The hole shape was as shown in Fig. 1, the corner θ smaller than 60° was 50°, the corner C was 190', and the angle was 120°0.
Using a spinning nozzle with dimensions t of 3 & 3μ, single fiber 11M
6 denier, total denier 2) E 36 [10
A 0 denier crimped acetate fiber aggregate was produced. The fiber aggregate was processed into a filter with a diameter of 7.87 m and a length of 102 cm using a commonly used filter manufacturing machine.
It was rolled up into a cylindrical filter plug. The material composition of 10 filter plugs at this time is acetate fiber 5.35? , triacetin α32t1 roll paper and other u78
It was set as y.

The ventilation resistance and hardness of this filter plug are shown in Table 1 along with the nozzle hole circumference Q L , nozzle hole area S, and 8F value.

Example 2 Hole shape as shown in Figure 3! The corner θ is 30°, the corner C is 210°, and the angle 120° 1 dimension t is 45.7
A crimped acetate fiber aggregate and a filter 1 lug were produced in the same manner as in Example 1, except that a μ spinning nozzle was used, and the results of 7 were also shown in Table 1.

Example 3 The hole shape M is as shown in Fig. 4, the corner θ is 30°, the angle C is 210°, the angle is 120°, and the dimension t is 3 & 7μ.
, a crimped acetate fiber aggregate,
Furthermore, filter plugs were manufactured and the results are also shown in Table 1.

Example 4 The hole shape is km as shown in Fig. 5, the corner θ is 40°, the angle C is 230°, the dimension t is 51.7μ, and the dimension is 5.0.
A crimped acetate fiber aggregate and a filter plug were produced in the same manner as in Example 1, except that all μ spinning nozzles were used, and the results are shown in Table 1.

Comparative Example: An equilateral triangle with an angle of θ or 60° as shown in Figure 2, -
11! Same as the example except that a spinning nozzle with side t or 58p is used. A condensed acetate fiber aggregate and a filter plug were produced, and the results are also shown in Table 1.

Here, the symbol FD is the ventilation resistance of the filter 1 lug when 17.5 mg/sec of air is passed through the water column 5aiH2
0, and the symbol Hd is the value obtained by subtracting the concavity of the filter plug from the original diameter when a load of 300 t is applied for 15 seconds perpendicular to the length direction of the filter plug and at the center of one filter lug. , divided by the original diameter plus 100
Usually used to indicate the hardness of a filter plug.

〔Effect of the invention〕

As is clear from Table 1, cigarette filter plugs made of acetate fibers spun by an uninvented acetate fiber spinning nozzle with a large SF value have the same fiber fiber concentration, the same fiber filling amount, and the same triacetin addition. Under the sword, it has higher airflow resistance and better sand resistance.

[Brief explanation of the drawing]

FIG. 2 shows the discharge hole shape of a commonly used equilateral triangular acetate fiber spinning nozzle, and FIGS. 1 and 3 to 6 show the shape of the acetate fiber spinning nozzle of the present invention. Each (1 discharge hole shape is shown. In the figure, the symbols θ, O, and D indicate the respective angles, and b and t indicate the respective lengths.

Claims (1)

[Scope of Claims] 1) A nozzle having a polygonal nozzle hole having three or more corners smaller than 60°, the nozzle having a nozzle hole circumference (L
) and the nozzle hole area (S) is 5.1≧L^2/
An acetate fiber spinning nozzle characterized in that (4xS)≧1.7. 2) The acetate fiber spinning nozzle according to claim 1, wherein the tip of the corner portion smaller than 60° is notched, and the length (b) of the notch portion is in the range of 3μ or more and 12μ or less. 3) The acetate fiber spinning nozzle according to claim 2, wherein the corners exceeding 180° are smoothly curved.