JPS5828380B2 - How to crimp multifilament - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for crimping multifilaments.

Conventionally, a multifilament made of thermoplastic synthetic fiber is used together with a fluid of 200°C or higher, such as heated air or superheated steam, into a hollow housing, a needle inserted into the housing from above, and a needle inserted into the housing from below. It is known to crimp a multifilament by passing it through a fluid nozzle assembly (hereinafter simply referred to as fluid nozzle) consisting of a venturi and a fluid inlet tube attached to the middle of the housing, and then impinging on a moving surface. It is.

This will be explained below with reference to FIG. 1, which is a process diagram to which the present invention is also applied.

That is, a thermoplastic polymer is spun as a synthetic fiber multifilament 3 from a melt spinning device 10 nozzle 2, and after cooling the multifilament in a cooling chimney 4, it is brought into contact with an oiling roller 5 to be oiled, and then A multifilament is prepared by either taking it off in step 6 and winding it as an undrawn yarn using a winding device (not shown), or by subsequently drawing it as shown in FIG.

When drawing the multifilament subsequently, the 20th
- the moving surface 1 is passed through a fluid nozzle 9 together with air or superheated steam (hereinafter simply referred to as fluid) 8 heated to 200° C. or higher after being stretched by a factor of 3 to 5;
It is known to crimp a multifilament by impacting it with zero.

The crimped multifilament that has left the moving surface 10 is taken up by the 30th roller 12 via a guide 11 provided as necessary, and finally wound up on a winding machine 13 to become cheese 14.

In the above method, the multifilament is disturbed by the fluid in the fluid nozzle and becomes crimped, and further collides with a moving surface to cause impact buckling, which promotes the crimping.

Therefore, the moving surface may have any structure as long as it causes impact buckling (Japanese Patent Laid-Open No. 5167445).

This method, especially the method in which the synthetic polymer is spun and drawn all at once and then the above-mentioned crimping method is immediately applied, is a very good method because it can yield good crimped multifilaments with high productivity. Is recognized.

However, there is still room for improvement in the bulkiness of the crimped multifilament obtained by the above method in light of the quality of the final product of the crimped multifilament, such as a carpet.

In general, when trying to improve bulkiness, productivity must be reduced inversely.Therefore, there is a need to improve bulkiness and uniformity while maintaining high productivity. In response to this need, the inventors searched for a more ideal method for imparting crimpability to multifilaments, and as a result, they arrived at the present invention.

Therefore, an object of the present invention is to simultaneously improve productivity, bulkiness, and uniformity in the above-mentioned known multifilament crimp method.

This objective is achieved by the following method.

That is, the above object is to carry a multifilament made of thermoplastic synthetic fiber together with a fluid of 200° C. or higher into a hollow housing, a needle fitted into the housing from above, a venturi fitted from below, and a hollow housing. A multifilament crimp method comprises passing the multifilament through a fluid nozzle assembly comprising a fluid introduction pipe attached to the middle of the nozzle and colliding with a moving surface. The multifilament that has collided with the moving surface is filled and passed through a filling zone defined by the end face of the Venturi outside the ejection hole and the moving surface with which the multifilament collides, and the center of the needle is passing the multifilament into the fluid nozzle assembly while shifting the line from the centerline of the venturi toward the filling zone so that the centerline in the ejection direction of the multifilament is different from the centerline in the ejection direction of the fluid; This is achieved by letting.

The method of the present invention will be explained in more detail with reference to the drawings.

The overall process to which the method of the present invention is applied is the same as the conventional method shown in FIG.

However, in the method of the present invention, the parts indicated by chain lines in FIG. 1, that is, the structure of the lower end surface 97 of the fluid nozzle 9, the structure of the moving surface 10, and the relationship between the two, which will be described later, are extremely specified. The method is significantly different from conventional ones.

FIG. 2 is a cross-sectional view showing a typical example of an apparatus used in carrying out the present invention.

First, the most preferable structure of the fluid nozzle 9 will be explained.
The fluid nozzle includes a hollow housing 91, a needle 92 fitted from above, a venturi 93 fitted into the housing from below the needle, and an introduction pipe 94 for guiding the fluid 8 from the middle of the housing to the hollow part thereof. It essentially consists of.

When the multifilament 3 is introduced into the needle 92 of the fluid nozzle 9, and the fluid 8 is introduced from the introduction pipe 94, the fluid enters the venturi 93 from around the needle 92 so as to surround the multifilament 3, where the fluid Due to the disturbance, the multifilament 3 is crimped and ejected from the ejection hole 95 together with the multifilament 3.

In the apparatus used in the method of the present invention, the center line C1 of the needle 92 is offset from the center line C2 of the venturi 93 toward a filling zone, which will be described later.

When a fluid nozzle with such a structure is used, the fluid is ejected in the direction A (in Fig. 2, it is the center line C2 of the venturi).
) and the multifilament ejection direction B
and become different.

This is because the inner wall 96 of the venturi 93
It widens toward the tip side, and the center line C
This is because 1 and C2 are different.

In the present invention, the angle θ between the two directions A and B is
The structure and usage conditions should be selected so that the angle is preferably 3 to 45 degrees.

By doing this, the multifilament is disturbed at an eccentric position within the fluid bundle, the multifilament imparts crimp, and the fluid and the multifilament collide with the moving surface in a more separated state. As a result, separation between the fluid and the multifilament progresses, and on the other hand, the fluid does not significantly disturb the multifilament after colliding with it on the moving surface, and the crimped multifilament is more orderly filled in the filling zone described below. The effect is demonstrated.

Note that in the above description, the jetting direction refers to the center of the fluid bundle or the average center of the multifilament thread path.

The multifilament 3 that has passed through the nozzle is ejected from the fluid nozzle 9 together with the fluid 8, collides with the moving surface 10, causes collision buckling, and the crimp imparted by the disturbance of the fluid 8 within the nozzle is promoted.

The multifilament 3 further passes through a filling zone 98 delimited by a fixed lower nozzle end surface 97 and a moving uppermost surface 101 of the moving surface.

In the filling zone 98, the multifilament 3 is crimped by pushing.

Therefore, the multifilament 3 that has passed through the filling zone 98 is further crimped because the three-dimensional crimps caused by the disturbance by the fluid 8 in the nozzle and the collision with the moving surface are further crimped by the pushing. This results in increased length and more uniform crimped yarn.

Here, the length of the filling zone 98 in the moving direction of the moving surface 10 and the distance between the lower end surface 97 of the fluid nozzle and the uppermost moving surface 101 of the moving surface are very important in the present invention.

That is, the key points of the present invention are how to stably push the multifilament 3 ejected from the fluid nozzle 9 into the filling zone 98 and how to give the multifilament 3 firmly crimp in the filling zone. is the length L of the moving surface of the filling zone in the moving direction of 10 mr.
n or more, and the narrowest distance H between the lower end surface of the fluid nozzle and the moving surface of the moving surface is 3 to 10 mm.

The length L of the moving surface of the filling zone in the moving direction is 10 m.
The reason for setting it below 107n71 is that if the multifilament is set below 107n71, the multifilament coming out of the fluid nozzle will immediately fly out from the lower end surface of the nozzle after colliding with the moving surface, and the filling zone will not be filled.

That is, if the multifilament emitted from the nozzle does not further fill the filling zone after colliding with the moving surface, good crimp cannot be obtained.

Furthermore, the reason why the narrowest distance H between the lower end surface of the fluid nozzle and the moving surface of the moving surface is set to 3 to 1Q mm is that the smaller the gap is, the more preferable it is from the viewpoint of crimping due to pushing.
If the value is less than L, the fluid emitted from the fluid nozzle collides with the moving surface, causing a large rebound, and the suction tension of the multifilament at the inlet of the fluid nozzle decreases, causing the multifilament to conversely
There is a risk that yarn breakage may occur due to reverse winding, or the multifilament may become clogged between the fluid nozzle and the moving surface, making yarn spinning impossible.

On the other hand, if the gap H is set to 10 degrees or more, it is the same as if the length of the moving surface of the filling zone in the moving direction was lowered by 10 mvtJ2J, and after the multifilament coming out of the fluid nozzle collides with the moving surface. There is a possibility that it will immediately fly out from the lower end surface of the nozzle.

Furthermore, in order to effectively achieve the object of the present invention, the method of the present invention should be implemented using an apparatus having the following structure.

That is, when the fluid nozzle shown in FIG. 3 (a perspective view of which is shown) is fixed to the lower end surface of the nozzle in such a manner that it is possible to produce a crimped yarn in front of the moving surface 10. , the nozzle lower end surface 97 is provided with a step consisting of two upper step portions 93A1 and 93A2 closer to the moving surface 10 and a lower step portion 93B farther away.

Therefore, the lower end surface 9γ is formed from the end surfaces of 93A1, 93A2, 93B, etc.

Furthermore, a narrow portion 93C is provided between the two upper step portions 93A and 93A2, which serves as a passage for the multifilament crimped by the fluid nozzle.

Therefore, when the fluid nozzle 9 is viewed from another angle, the side view shown in FIG. 4 is desired, and the narrow portion 93C appears concave.

In this case, the space sandwiched between the uppermost surface 101 of the moving surface 10 and the upper bottom 93C1 of the narrow portion 93C and the two side walls 93C2 and 93C3 is the filling zone 9 referred to in the present invention.
It becomes 8.

Here, the crimped filament that collided with the moving filter 10 behaves as shown in FIG. 2 and fills the filling zone, and the heat of 200°C or more that the fluid has is transmitted from the wall of the filling zone to the multifilament. This completely improves the crimp characteristics.

The stepped portion of the lower end surface used in the present invention may be formed integrally with the venturi, or may have a structure in which an adapter having a separately formed stepped portion is attached to the venturi itself.

The moving surface 10 used in the present invention is a breathable moving surface.

Particularly preferably, a method is adopted in which the crimped multifilament is sufficiently cooled by sucking air from inside the moving surface, that is, from the side opposite to the side where the fluid nozzle is installed, and the crimps are fixed.

Further, the moving surface may be, for example, a perforated plate having a large number of fine pores 102 as shown in FIG. It is better to use a board.

The reason for this is that when a wire mesh is used, the single threads of the multifilament get caught between the intersecting metal wires, and single threads tend to break when the multifilament is taken out from the moving surface.

Compared to wire mesh, the use of a perforated plate is preferable because it does not have the above-mentioned problems and buckling and crimping due to collisions is increased compared to wire mesh.

The pores 102 of the moving surface 10 used in the present invention have an average diameter of 0.3 to 1.5 mm, preferably 0.6 to 1.0 mm, in the range of single filament fineness of 6 to 50 denier of the multifilament to be handled. The average aperture ratio, that is, the ratio of the total area of all pores 102 to the apparent total surface area of the moving surface 10, is in the range of 10 to 50, preferably 20 to 40.
It should be ☆.

Unless it is within these ranges, the object of the present invention cannot be fully achieved.

Note that the crimped multifilament that has left the moving surface 10 is taken up by the 30th la after passing through a guide 11 provided as necessary, as in the conventional method, and finally wound up on a winding machine 13 to become cheese. .

The crimped multifilament thus obtained has excellent bulk and uniformity and can be efficiently produced while maintaining high productivity.

Next, the present invention will be described with reference to specific examples.

Example 1 Polycapramide chips with a relative viscosity of 2.84 were melt-spun at 280°C, spun using a spinneret with a Y-shaped cross section, drawn, and
Processing was carried out continuously, and a 1300 denier 68 filament was processed.

The spinning speed was 500 m/min (10th la), 2000 m/min (20th la), and a stretching ratio of 4.0.
And so.

The 20th la was heated to 150°C, and heated air at 270°C was used as the fluid.

The shape of the moving surface was a circular perforated plate with a hole diameter of 0.8φ and a porosity of 20%.

In addition, air is sucked from inside the moving surface and the suction static pressure is 150 mmH2.
Aspirated at 0.

A fluid nozzle having the shape shown in FIGS. 3 and 4 was used.

Experiments were carried out by changing the size of the filling zone of the fluid nozzle, and the results shown in Table 2 were obtained.

The crimped yarn obtained in A2.3.4.7 in the table was a yarn with excellent bulkiness and no wings or walnuts.

The carpet obtained by tufting this product showed extremely good quality and elegance.

Example 2 A polycapramide 2600 denier 136 filament was pressurized in the same manner as in Example 1.

The spinning speed and stretching ratio were the same as in Example 1. The 20th la was heated to 155°C, and heated air at 275°C was used as the fluid.

The fluid nozzle is an eccentric type (θ - 15°), the gap H between the nozzle end face and the moving surface is 8 mm, and the moving length L of the moving surface in the filling zone is 501n711, resulting in improved yarn reeling performance and processing stability. A yarn with good quality as shown below was obtained.

Fineness: 2645 denier, elongation rate: 28.5%, boiling water shrinkage rate: 3.9% The obtained crimped yarn has excellent bulkiness without wing or walnut, and the carpet obtained by tufting it is extremely bulky. Showed good dignity and quality.

[Brief explanation of the drawing]

FIG. 1 is a process diagram to which the method of the present invention is applied (it is also a process diagram for explaining the conventional method). FIG. 2 is a longitudinal cross-sectional view of a portion of the fluid nozzle and moving surface used in the method of the present invention. 3 and 4 are perspective and side views of the most preferred fluid nozzle for use in the present invention. FIG. 5 is a plan view showing a portion of the moving surface. 1... Melt spinning device, 2... Spinneret, 3
...Multifilament, 4...Cooling chimney 5...Oiling roller, 6.
...10th la, 7th pa°...20th la, 8th
...Fluid, 9...Fluid nozzle 10...
...-moving surface, 11... guide, 12...
...30th-ra, 13... Winder, 14...
...Cheese, 91...Housin, 117"
, 92...Needle, 93...Venturi, 94...Introduction pipe, 95...Blowout hole, 96...Inner wall of Venturi, 97...
...Nozzle bottom end surface, 98...Filling zone,
C1... Center line of the needle, C2...
Venturi centerline.

Claims (1)

[Claims] 1 Multifilament made of thermoplastic synthetic fiber 2
It consists of a hollow housing, a needle fitted into the housing from above, a lupenture fitted from below, and a fluid introduction pipe attached to the middle of the housing, together with a fluid at a temperature of 00°C or higher. In a method for crimping a multifilament, the multifilament is crimped by passing it through a fluid nozzle assembly and colliding with a moving surface. The multifilament that has collided with the movable surface is passed through a filling zone defined by a colliding moving surface while being filled with the multifilament, and the center line of the needle is shifted from the center line of the Venturi toward the filling zone side. A method for crimping a multifilament, comprising passing the multifilament through the fluid nozzle assembly while making a center line of the multifilament in a jetting direction different from a centerline of the fluid in a jetting direction.