JP2588901B2 - Washing equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a water washing apparatus, and more specifically to water washing of a spun fiber bundle such as, for example, polyacrylonitrile (hereinafter sometimes referred to as PAN) fiber. The present invention relates to a water washing device that can be suitably used.

[Prior art and its problems] For example, high-strength fibers such as PAN-based carbon fibers are materials having a high modulus of elasticity, and their strength is easily affected even by fine scratches on the surface.

Therefore, for example, when producing a precursor (precursor) of a PAN-based carbon fiber, it is necessary to produce a fiber with as few scratches as possible.

This precursor is prepared by spinning an undiluted spinning solution prepared by dissolving a PAN-based polymer in a solvent by a wet spinning method or a dry spinning method, and then washing with water to remove the solvent contained in the fiber, followed by drawing and drying and densification. It is manufactured by performing.

Incidentally, since the solvent that dissolves the PAN-based polymer has a high affinity for the PAN-based polymer, it is likely to remain in the fibers in the washing step after spinning of the spinning stock solution.

On the other hand, in the precursor of the PAN-based carbon fiber, it is said that the residual solvent amount is preferably 0.1% by weight or less, particularly preferably 0.05% by weight or less.

Therefore, in order to achieve the object, it is necessary to use a large amount of rinsing water, and a method of causing undesirable damage to the fiber, such as a high-speed rinsing method, has been constantly employed.

As an example, there has been proposed a method of using a vibro washer as shown in FIG. 6 to increase the washing efficiency (see Japanese Patent Application Laid-Open No. 59-36716).

The vibro washer used in this method includes a basket roller A having a large number of holes formed on its surface so as to have a porosity of 30 to 50%, and a petal-type runner B rotating inside the roller. When rotated, a radial pressure wave is generated in the water between the basket roller A and the fiber C such as a precursor, and the basket roller A
The fiber C is alternately moved in and out of a number of holes opened in the above-mentioned manner to perform water washing.

That is, the method using this vibro washer
The fibers C are brought into close contact with a basket roller A having an opening ratio of 30 to 50%, and the peripheral surface speed of the rollers A is rotated in accordance with the running speed of the fibers C, and simultaneously the runner B is rotated at a high speed to wash the fibers C with water. When the fiber is brought into contact with such a porous surface, the surface of the fiber is easily damaged, and it is difficult to increase the peripheral speed of the basket roller A to improve the washing efficiency. There's a problem. Also,
Since the washing water is made to alternately flow into and out of the holes of the basket roller A through the fiber bundle, the fiber bundle is intermittently pressed to the basket roller A, and especially in the dry-wet spinning, the fiber constituting the fiber bundle is formed. There is also a problem that fusion is likely to occur therebetween. Here, when fusion between fibers occurs, even if a high-strength precursor can be obtained,
Since the strength of the carbon fiber obtained from such a precursor is reduced as compared with the case where no fusion occurs, prevention of fusion between fibers has been desired especially in dry-wet spinning.

Further, in the method using the vibro washer, there is also a problem in operation that when the fibers are fluffed in the spinning process, the fluffs are sucked into the holes of the basket roller A and are wound around the roller A.

[Object of the Invention] An object of the present invention is to eliminate the above-mentioned problems, to improve the washing efficiency, to prevent fusion between fibers, and not to damage the surface of the fibers, and to prevent the fluff from winding. Is to provide.

[Means for Achieving the Object] As a result of intensive studies of the present invention in order to achieve the object, a water washing apparatus which can jet water for washing is excellent in washing efficiency and fusion between fibers. The present invention has been found out that it is possible to prevent the occurrence of damage to the surface of the fiber and to prevent the fluff from winding.

That is, the configuration of the first invention is a water washing apparatus including a guide for changing a running direction of the fiber bundle while performing water washing of the fiber bundle, wherein the guide has a guide rod formed in a hollow, Along with providing a flushing water introduction path inside the guide rod, a flushing water discharge port communicating with the flushing water introduction path is opened on a peripheral side surface that changes the running direction of the fiber bundle,
A flushing device characterized by being formed so as to spray flushing water onto the fiber bundle from the flushing water discharge port. The configuration of the second invention is to perform flushing of the fiber bundle,
A washing device comprising a guide for changing a running direction of the fiber bundle, wherein the guide forms a rotatable guide rod in a hollow, and a washing water introduction path is provided inside the guide rod. A flushing water discharge port communicating with the flushing water introduction path is opened on the circumferential side surface for changing the running direction of the bundle, and the flushing water is jetted from the flushing water discharge port to the fiber bundle and the inside of the guide rod. A flushing device characterized in that a shielding plate is provided between the flushing water introduction passage and the flushing water discharge port so as to be able to prevent the flushing water from jetting out in a direction other than the fiber bundle.

[Operation] The guide in the water washing apparatus of the present invention is installed and used at right angles to the running direction of the fiber bundle and in a horizontal direction.

In the present invention, the guide rod is hollowed to provide a flushing water introduction path, and a flushing water jet opening communicating with the flushing water introduction path is provided on a circumferential side surface for changing the running direction of the fiber bundle. is there.

Further, the washing water introduction path has an open end, and this open end is used as a washing water introduction port.

That is, the washing water conveyed from the outside is introduced into the washing water introduction passage in the guide rod from the washing water introduction port, and is jetted from the washing water jet port toward the fiber bundle. Here, if the guide rod is made rotatable,
In order to prevent the washing water from being inadvertently spouted in the direction other than the fiber bundle, the water is washed in the direction other than the fiber bundle by a shielding plate provided between the washing water introduction path and the washing water spout. Prevents spouting of water.

The rinsing water spouted from the rinsing water jet outlet applies a jet pressure to each fiber constituting the fiber bundle to loosen the fiber bundle and perform water washing while preventing fusion between the fibers. On the other hand, each fiber changes its running direction along the peripheral side surface of the guide rod in the take-up direction.

[Effects of the Invention] According to the present invention, (1) since water for washing is formed so as to be jettable toward the fiber bundle, it is possible to loosen the fiber bundle by applying a jet pressure to each fiber constituting the fiber bundle. (2) Therefore, while being excellent in water washing efficiency, there is no fusion between the fibers, and (3) since the guide surface does not directly contact the fibers,
The running direction of the fiber can be changed without damaging the fiber. (4) Since the washing water is jetted to the outside of the guide surface instead of the washing water coming and going alternately like a vibro washer, even if the fiber Even if a piece or fluff of the fiber comes into contact with the guide surface, the jet pressure acts in a direction to move the piece or fluff of the fiber away from the guide surface, so that the piece of fiber or the fluff does not wrap around the guide surface, and operability is improved. It is possible to provide a water washing apparatus having various advantages such as not causing a decrease.

EXAMPLES Next, examples of the present invention will be shown, and the present invention will be described more specifically.

FIG. 1 is an explanatory view showing an example of a water washing apparatus of the present invention.

As shown in FIG. 1, in this embodiment, the guide rod 1 is formed in a cylindrical shape.

As long as the material used for forming the guide rod 1 is not corroded by the residual solvent introduced by the fiber, the same material as the material used for forming the conventional guide roller can be used. Applied metal, ceramics such as titanium, alumina, titanium carbide and the like on the metal, those coated with Teflon, silicone, etc., and ceramics such as glass, alumina, titanium and zirconia. Bakelite and other hard plastics can also be used depending on whether or not the solvent remaining in the fibers is corrosive.

In the present invention, the guide rod 1 may be formed so as not to rotate, or may be rotatable. In this embodiment, the guide rod 1 is formed so as not to rotate. Guide rod 1 when guide rod 1 is formed to be rotatable
Is usually cylindrical, but when it is formed to be non-rotatable, the cross-sectional shape of the contact surface of the guide rod 1 with the fiber bundle can be, for example, a cubic parabola, a trochoid curve, or the like. . When the guide rod 1 is formed in a cylindrical shape, the radius of curvature of the peripheral side surface 2 for changing the running direction of the fiber bundle in the direction perpendicular to the running direction of the fiber bundle is usually
It is 10 to 200 mm, preferably 50 to 100 mm.

The state of the surface of the peripheral side surface 2 may be a mirror surface like a conventional guide roller or a matte surface. In order to prevent the fiber from being damaged when the fiber comes into contact with the fiber, it is preferable that the fiber does not have fine irregularities or a pointed tip, like the conventional guide roller.

On the peripheral side surface 2 , a washing water jet port 3 for jetting washing water toward the fiber bundle is opened.

The shape of the water outlet 3 for washing may be any shape as long as the liquid can be jetted uniformly in the width direction of the running fiber bundle. For example, as shown in FIG. It may have a slit shape that opens in the horizontal direction, or may have a plurality of rows of holes that are perpendicular to the running direction of the fiber bundle and that are horizontal. However, if holes are arranged along the running direction of the fiber bundle, some fibers receive the jet stream and some fibers do not. Therefore, the positions of the holes should be appropriately shifted.

Here, in the case where the washing water jet port 3 is formed in a slit shape, the slit width is usually 1 mm or less, preferably 0.2 to 0.5 mm. Further, it is preferable that the total length of the slit is slightly larger than the width of the running fiber bundle. Further, the number of slits is preferably 3 or more. If the number of slits is 2 or less, the washing efficiency may be reduced.

On the other hand, when the water jet port 3 is formed by a row of holes, the diameter of the holes is usually 4 mm or less, preferably 0.5 to 2 m.
m. Further, the entire length of the portion where the holes are formed in a line is the same as the entire length of the slit. The number of rows of holes is preferably 6 or more from the viewpoint of washing efficiency.

As shown in FIG. 2, the inside of the guide rod 1 is hollow, and a washing water introduction path 4 is provided here.

The flushing water introduction passage 4 communicates with the flushing water jet port 3, and has an opening end as a flushing water introduction port 5.

For example, as shown by a phantom line in FIG. 1, a washing water extraction pipe 20 for transporting washing water from the outside is attached to the washing water introduction port 5, and this washing water extraction pipe 20 is It is preferable to use the guide rod as it is. The connection between the rinsing water inlet 5 and the liquid flow pipe 20 is made, for example, by forming a thread 6 on the inner peripheral surface of the rinsing water inlet 5 as shown in FIG. It can be performed by screwing the tip of the flow pipe 20.

That is, the washing water transferred from outside to the inside of the liquid flow pipe 20 by an appropriate transfer means such as a pump is
The washing water is introduced into the washing water introduction passage 4 from the washing water introduction port 5 and further ejected from the washing water ejection port 3 toward the fiber bundle.
When the guide rod 1 is rotatable, its rotating shaft is preferably used as the water inlet 5 for washing.

If hot water is used as the washing water, it can be used for hot water stretching.

The jetting amount of the washing water can be appropriately set according to the thickness and tension of the fibers constituting the fiber bundle, but is usually in the range of 10 / min to 500 / min per 10 cm of the width of the fiber bundle. .

When the guide bar 1 is formed to be rotatable, as shown in FIG.
Should be provided.

The shielding plate 7 is for preventing the flushing water from being sprayed in a direction other than the fiber bundle, and has a cut-out portion facing the fiber bundle.

That is, when the washing water jet 3 moves to a position not facing the fiber bundle with the rotation of the guide rod 1, the communication between the washing water jet 3 and the washing water introduction path 4 is cut off. It is fixed so that it cannot rotate.

The rinsing device 8 of the present invention may be used as a guide to be immersed in a rinsing tank as shown in FIG. 4, for example.
It may be used for all guide rollers including the speed control roller used in the washing step, but preferably used for all guide rollers.

However, when a large stretching is performed in the washing tank, if the washing device 8 of the present invention is used for all of the plurality of speed control guides, the fibers may slip and the speed may not be controlled. In that case, it is preferable to use only the speed control roller closest to the washing tank, or to use the speed control roller closest to the washing tank and a guide immersed in the washing tank.

In order to improve the washing efficiency, it is preferable to install a washing device 8 on both sides of the fiber and wash both sides of the fiber as shown in FIG.

(Reference Example 1) A spinning stock solution composed of a polyacrylonitrile / pure zinc chloride concentrated aqueous solution (polymer weight: 130,000, solution viscosity at 45 ° C: 300 poise) having a polymer concentration of 6.5% was 0.2 mm in diameter and 12 holes.
It is discharged from the spinning nozzle of No. 00, the coagulation bath temperature is 2 ° C., the coagulation bath zinc chloride concentration is 27%, the discharge linear velocity is 10 m / min, and the draft rate is 0.
8. Spinning was performed at a dry length (interval between the nozzle tip surface and the coagulation bath liquid surface) of 6 mm.

Next, using a washing device 8 installed in the state shown in FIG. 4, the fibers were washed with a washing water temperature of 18 ° C., an ejection amount of washing water per fiber bundle width of 10 cm of 150 / min, and a take-up speed of 8 cm.
Water washing was performed under the condition of m / min.

Thereafter, stretching, application of an oil agent, and drying and densification were performed according to a conventional method, and further stretching was performed in steam to obtain a precursor. The obtained precursor has a diameter of 10 μm and a tensile strength.
The weight was 75 kg / mm ² and the elongation was 15%.

This precursor was oxidized in air at 240 to 260 ° C., and subsequently carbonized at a maximum temperature of 1300 ° C. in a nitrogen atmosphere to obtain carbon fibers.

The obtained carbon fiber had a diameter of 5.2 μm and a strand strength of 5
It was 23 kg / mm ² .

(Reference Example 2) In the above-mentioned Reference Example 1, a vibrator washer (basket roller opening ratio 40
%), And a precursor was obtained in the same manner as in Reference Example 1 except that water was washed under the conditions of a peripheral speed of the basket roller of 8 m / min. The resulting precursor has a diameter of 10
μm, tensile strength 72 kg / mm ² , elongation 15%. The precursor obtained in this reference example showed some fusion. Further, the winding of the filament sometimes occurred in the basket roller, and in each case, the thread was broken unless it was removed.

Next, this precursor was treated in the same manner as in Reference Example 1 to obtain a carbon fiber.

The obtained carbon fiber had a diameter of 5.2 μm and a strand strength of 3
It was 92 kg / mm ² and the strand strength was inferior to that of Reference Example 1.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a washing device of the first invention,
FIG. 2 is a sectional view of the same, FIG. 3 is a partially cutaway explanatory view showing an example of the flushing device of the second invention, FIGS. 4 and 5 are explanatory views showing a use state of the flushing device of the present invention, FIG. 6 is an explanatory view showing an example of a conventional washing machine. DESCRIPTION OF SYMBOLS 1 ... Guide rod, 2 ... Peripheral side surface, 3 ... Rinse water spout, 4 ... Rinse water introduction channel, 5 ... Rinse water inlet, 8
…… Washing equipment.

 ────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-59-36716 (JP, A) JP-A-59-168112 (JP, A) JP-A-50-95585 (JP, A)

Claims (2)

(57) [Claims] 1. A water washing apparatus comprising a guide for changing a running direction of a fiber bundle while washing the fiber bundle with water, wherein the guide has a guide rod formed in a hollow, and the guide rod has a hollow inside. A washing water introduction path is provided in the washing machine, and a washing water discharge port communicating with the washing water introduction path is opened on a peripheral side surface for changing the running direction of the fiber bundle, and the washing water is jetted from the washing water discharge port to the fiber bundle. A water washing device characterized by being formed so as to perform. 2. A water washing apparatus comprising a guide for changing the running direction of a fiber bundle while washing the fiber bundle with water, said guide forming a rotatable guide rod in a hollow shape. A washing water introduction path is provided inside the rod, and a washing water discharge port communicating with the washing water introduction path is opened on a peripheral side surface for changing the running direction of the fiber bundle, and the fiber bundle is washed with water from the washing water discharge port. A shield plate is provided between the rinsing water introduction path and the rinsing water discharge port inside the guide rod as well as the rinsing water, and formed so as to be able to prevent rinsing of the rinsing water in a direction other than the fiber bundle. A washing device characterized by comprising: