JPS5947066B2 - Continuous filament feeding device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a continuous filament delivery device, in which a large number of melt-spun continuous filaments are pulled by an air stream, and then the individual filaments are transferred to another material having a different charge series. This is a towing/feeding device that uniformly charges the filaments by rubbing against each other, and uses the charging to exert a repulsive force between the filaments, thereby making it possible to produce a web with good single filament dispersion.

In the so-called spunbond method, a nonwoven fabric manufacturing method in which a large number of synthetic fiber filaments are extruded, pulled by high-speed airflow, and then continuously formed into a web, it is possible to disperse the filaments uniformly and without unevenness. , is extremely important in order to obtain a nonwoven fabric with a uniform basis weight.

As one method, a method has been proposed in which the filaments are charged and the electrical repulsion between the filaments is utilized to improve dispersibility. Possible methods for charging a filament include charging it by passing it through ionized air, or applying conductive treatment to synthetic fibers, which are normally non-conductive, and directly applying a high voltage to charge them. There is. However, in the spunbond method, in which a curtain made of filaments is sent out at extremely high speeds using high-speed airflow, it is not only difficult to apply a sufficient charge to the filaments using the above method, but also causes significant equipment damage. Moreover, since it requires high voltage, it is extremely dangerous and impractical. On the other hand, the method of applying electric charge by rubbing the fibers is not dangerous and requires simple equipment. This technique is disclosed in Japanese Patent Publication No. 37-4993. Here, before the filament is introduced into the traction device, the filament is brought into contact with a substance having a different charge series to charge the filament and disperse the filament. In this case, the filaments are electrically charged before entering the drawing section, but if the filaments are rubbed to the extent that a sufficient charging effect occurs, the spinning speed will be reduced and the drawing of the filaments will be hindered, or the filaments will become electrified against the inner wall of the drafting device. The disadvantage was that the problem of electrostatic adhesion occurred. Therefore, in consideration of these points, Japanese Patent Application Laid-Open No. 50-6837 proposed a method of triboelectrically charging after traction to improve dispersibility.
The publication number will be shown. In this method, a curved tube section is provided following the pulling section, and the filament is charged by rubbing against the inner surface of the curved tube. In this case, since the filaments are brought into contact along the inner surface of the curved tube, if the friction is strong enough to cause a charging effect, the traction effect will be affected and the spinning speed will decrease, that is, there will be a tendency for the yarn to become undrawn. Not only is it impossible to obtain a nonwoven fabric with sufficient physical properties, but it is also difficult to rub each filament to the same degree, which tends to cause unevenness in the dispersion, and furthermore, the filaments may cause static electricity on the friction curved pipe or other areas. There are drawbacks such as the tendency for threads to stick and cause thread jams. In order to prevent this, if the friction in the curved pipe section is weakened, the amount of charge on the filament will be insufficient and the dispersibility will deteriorate. This invention is a technical solution to the above problems, and the filaments are drawn in a straight line by introducing a large number of continuous filaments into the guide groove of a narrow rectangular slit and pulling the filaments together with a high-pressure air flow. This device arranges the filaments and causes them to collide with an inclined plate provided below the filament guide groove to generate a frictional charge and uniformly disperse the filaments.

Figures 1 and 2 show an outline of a continuous filament delivery device. The filament 2 extruded from the spinning device 1 enters the rectangular delivery device 3, passes through the thread guide groove 4, and becomes a curtain of filaments. Board 6 provided below
The fibers collide with the fibers, become electrically charged, are completely dispersed, and are collected as a web on the fiber collection device 5.

In the feeding device 3, the filament vertically descends through the narrow guide groove 4 together with the air jetted downward from the high-speed air jet hole T, thereby pulling the filament strongly downward and heightening it. Descend to speed. Then, it collides with the inclined plate 6 provided at the lower end of the thread guiding groove 4. The filament is charged by the frictional electricity generated at this time, and the filament is uniformly dispersed and ejected by the repulsive force. ．． Here, it is necessary that a large number of filaments be arranged in a line in the thread guide groove, and then the individual filaments should collide with the inclined plate 6 to the same extent without unevenness, which may cause a decrease in the spinning speed or other problems. It is possible to completely disperse high quality filaments and form a good web while avoiding the problems seen in the prior art. The results of experiments conducted on the traction and delivery device having the above configuration are as follows.

Output amount: 200 from a rectangular spinning spout with 400 spinning holes
9/1 "The spun 6-nylon filament was introduced into a rectangular sucker with a thread guide groove width of 300 m, and a high-speed air flow jetting groove 1 was introduced.
After pulling the filament by blowing out compressed air at a rate of 200 Nm"/h, the filament is struck against the inclined plate 6 made of hard chrome-plated iron plate attached to the lower end of the thread guide groove, charged and discharged, and sent to the feeding device. It was collected on the lower moving conveyor to produce a web of 309/m'.

Experiments were conducted by varying the width and length of the thread guide hole, the length of the inclined plate, and the angle of inclination, and the results are shown in Table 1 attached hereto.
Here, the basis weight variation rate was used as a measure for evaluating the uniformity of the web.

The weight fluctuation rate is 3 for the size of width 25HR and length 1007HR.
Samples were taken from 0 points, the weight of each sample was measured, and the weight was calculated using the following formula. Maximum weight - Minimum weight Variation rate of basis weight n = ×100 Average weight If this value is smaller than 5%, it can be said that the uniformity of the filament distribution is sufficiently excellent.

Further, the charged voltage of the filament was measured using a current collecting potential measuring device KS-325 manufactured by Kasuga Denki. Note that △n is the birefringence index. Here, it is necessary to set the thread guide groove interval d of the filament feeding device to 2 mm or more and 107 gt or less.
This becomes clear from Examples 1 and 5.

In other words, in this device, since the filament is pulled by airflow, the length of the thread guiding groove is at least 200 mm.
m or more, and at the width 1 [in Example 1], the resistance between the airflow and the thread guide groove becomes large, and the spinning speed decreases due to a decrease in filament traction force, that is, the physical properties of the single yarn decrease. cause In some cases, a backflow phenomenon of high-speed airflow toward the soccer entrance occurs. On the other hand, the width d is 1
If it exceeds 0 to 1 gt (Example 5), the filament traction efficiency decreases and the physical properties deteriorate, and the filaments must be arranged in a line in the guide groove to collide regularly with the inclined plate. becomes difficult, and the electrostatic voltage is also low.
A uniform web cannot be obtained. In addition, the length 1 of the thread guiding groove from the high-speed airflow jetting groove 7 to the inclined plate must be at least 200?1iR or more, and at 100giR in Example 6, the filaments were lined up in the thread guiding groove due to the influence of the high-speed airflow. The filaments do not separate and come into contact with the inclined plate, and only some of the filaments come into contact with the inclined plate while most of the other filaments do not. Therefore, the amount of charge is small and the dispersibility is poor.

When 11 becomes 200: or more, it becomes possible to arrange the filaments in a line at the bottom of the thread guiding groove. Although it is not listed in the table, is 1, 1000? If it exceeds , the resistance between the high-speed airflow and the wall surface of the yarn guiding groove increases, reducing the traction efficiency and deteriorating the physical properties of the fiber. Therefore 10007
! It is desirable that it is below Gt. Mounting angle θ of inclined plate
is preferably in the range of 20° to 60°, and 20° in Example 11
If it is less than 100°, the amount of charge due to frictional effects decreases, resulting in poor dispersibility and difficulty in forming a uniform web.

In Example 14 where θ exceeds 60°, the frictional resistance between the inclined plate and the high-speed airflow or the filament becomes significantly large, the spinning speed decreases, the fiber is not pulled, the denier becomes thick, and its physical properties deteriorate. do. Furthermore, the length 12 of the inclined plate 6 is 507! It must be below IR and at least long enough for the filament to collide with it. As shown in Example 10, when the thickness exceeds 50, the filament electrostatically adheres partially to the inclined plate, causing unevenness and increasing the rate of variation in basis weight. In addition, for the purpose of preventing turbulence of high-speed airflow or other needs, an inclined upper plate 6' may be provided opposite to the inclined plate 6 as shown by the dotted line in FIG. 2.

What is particularly important here is to use a material for the inclined plate that is different from the filament in terms of charge order, and to completely seal the gap between the thread guide groove and the inclined plate, so that the material has a different charge order. If it is close to the target, the amount of charge due to friction will be small,
A sufficient dispersion effect cannot be expected. Furthermore, if there is a gap between the wall surface of the thread guide groove and the inclined plate 6, not only will airflow leak and the filament get caught, but it will also attract air from the outside and disrupt the filament row. hand,
A uniform web cannot be obtained. The present invention not only improves uniformity in webs made of a single polymer, but can also be used to form mixed webs made of two or more types of continuous filaments.

Furthermore, an example performed using an apparatus that satisfies the above conditions will be shown.

Example 15 Under the conditions of Example 3 in Table 1, 30?1 parallel to the inclined plate 6
The upper plate 6' of the gt inclined plate was installed so that the gap therebetween was 4 gourds, and a web was formed.

At this time, the filaments are arranged in a straight line at the bottom of the guiding groove,
The individual filaments were struck evenly and equally violently against the inclined plate 6. The charged voltage of the filament deposited on the conveyor is 23kV) Denier 2.0)ΔN
O. O33, the basis weight variation rate was 4.3%, and the web was sufficiently uniform. Example 16 Output amount 400 from a rectangular spinneret having 400 spinnerets
g/threshold, material polyethylene terephthalate filament, thread guide groove width (depth) 300mm, d=5wt. 1,=5
00, compressed air consumption 250N7713/H, l2=
A web of 309/m" was obtained with 3071gt and θ=40°.

Its charging voltage is 13kW, denier 2.2, ΔNO. O6
2. A good web could be obtained with a basis weight variation rate of 4.7. Example 17 Output amount 200 from a rectangular spinneret having 200 spinnerets
9/Produced T-spun polyethylene terephthalate and another rectangular spinneret having 200 spinnerets to produce a discharge amount of 100
At the same time, the 6-nylon filament spun at 9/i was thread-guiding groove width (depth) 3007 gt, d = 5, 1, = 5.
007HR, compressed air amount 250Nm゜/H, l2=30
A web was made with W, θ=40°.

As a result, the charging voltage was 18 kW, the basis weight variation rate was 4.9%, and a good web was obtained.

[Brief explanation of the drawing]

FIG. 1 is an explanatory view showing the state of use of the present invention, and FIG. 2 is a sectional view of the traction and feeding device. 1... Spinning device, 2... Filament, 3... Rectangular traction and feeding device, 4...
... Thread guiding groove, 5... Collection device, 6...
Inclined plate, T...fumarole.

Claims (1)

[Claims] 1 having a rectangular thread guide groove with a narrow width d of 2 to 10 mm and a vertically long (length l_1 of at least 200 mm);
In contrast, it has a built-in injection function that blows pressurized air downward, and is installed at the lower end of the thread guide groove with an inclination angle θ of 20 to 60 without any gaps. An inclined plate composed of (length l_2 is 50 m
A continuous filament delivery device that arranges a large number of filaments in a curtain shape and collides with and charges an inclined plate.