JPH0351806B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a method and apparatus for producing long-filament pitch fibers, and in particular, the present invention relates to a method and apparatus for producing long-filament pitch fibers. A method for producing long pitch fibers, which is a precursor of long carbon fibers, by collecting and storing them in the form of one strand, and an air ejector used therein. Regarding. (Prior art) In order to produce long fiber pitch fibers, which are precursors of long carbon fibers, from coal-based or petroleum-based raw material pitch, the raw material pitch is heated and melted to form a large number of pitch fibers. After pressure extrusion spinning, it is necessary to collect and store it in the form of a single strand. One reason is that
This is because the filaments that form the strands need to be collected in an uncut state and at a stable take-up speed, and also because the fibers may become frayed or cut during the subsequent firing process. This is because it is necessary to avoid insufficient strength due to fibers being oriented in the wrong direction. However, since Pituchi fibers have extremely low strength, the process of collecting them into a single strand is extremely difficult.
Conventionally, various proposals have been made to improve this point. For example, in Japanese Patent Application Laid-Open No. 59-1724, a sizing agent is applied to a large number of pitch fibers immediately after melt-spinning through a spinneret using a spray-type device, and the sizing agent is passed through a first take-up roller to apply a traction force. The material is focused while being applied, and the focusing force is increased by taking it up with a second take-off roller and applying tension.
A method has been proposed for producing long fiber pitch fibers which are subjected to a static eliminator downstream and then stored in a can. In addition, in Japanese Patent Application Laid-open No. 60-252722,
In order to improve the problems of the manufacturing method of Publication No. 59-1724, such as low convergence and wrapping around the roller, a large number of melt-spun pitch fibers were first passed through a first air sucker and converged. Then, after applying a traction force with the first take-up roller whose static electricity has been removed by grounding, tension is applied through the second take-up roller whose electricity has been similarly removed by grounding, and the tension is applied to the first and second rollers. A method for manufacturing long-filament pitch fibers is proposed in which a sizing agent is applied with a spray-type device under tension between the fibers, the fibers are passed through a second roller, and the fibers are pulled by a second air sucker and stored in a can. has been done. In addition, as seen in the conventional proposed method above, in the method for producing long-filament pitch fibers, an air sucker is used in the process of collecting and accommodating a large number of pitch fibers into one strand due to the weak strength of pitch fibers. The air ejector 1 shown in FIG. 6 has conventionally been used as an air suction car.
This air ejector 1 includes a strand introduction part 2 having a strand introduction passage 2a and whose downstream end is formed as a needle part 2b, and a strand coaxially located downstream of the strand introduction passage 2a. A strand conveyance jet section 3 having a conveyance jet passage 3a and whose upstream end 3b surrounds the needle section 2b of the strand introduction section 2 and forms an annular slit 4 therebetween; a manifold section 5 having an annular manifold chamber 5a and an air inlet 5b of the annular manifold chamber 5a, and an annular manifold chamber 5 located around the strand introduction section 2 between the annular manifold chamber 5a and the annular slit 4;
A rectifying section 6 having a rectifying passage 6a that communicates the strand a with the annular slit 4, and a plurality of rectifying plates 6b arranged radially,
The manifold part 5 and the rectifying part 6 are made integrally, and the strand introduction part 2 can be moved up and down by rotating the upper screw mechanism 7 relative to these integral parts, thereby reducing the gap between the annular slits. The width is now adjustable. The strand sent from the strand introduction passage 2a is drawn by the air flow ejected from the annular slit 4, conveyed through the strand conveyance ejection passage 3a, and discharged from the outlet together with the air flow. (Problems to be Solved by the Invention) Among the conventional methods for producing pitch fibers mentioned above,
The proposal in JP-A-59-1724 was published in JP-A-60.
As described in Japanese Patent No. 252722, there were problems in that the resulting pitch fibers had low cohesiveness and were easily wound around the take-up roller. The reason for the low sizing property is that because a spray type sizing agent application device is used, there is a limit to the amount of sizing agent that can be sprayed, and a considerable portion of the sizing agent that is sprayed does not adhere to the pitch fibers. As a result, a sufficient amount of sizing agent is not applied, and in addition, the sizing agent adheres to only about 5% of the sizing agent, which means that the pitch fibers are not sufficiently wetted. It is conceivable that static electricity may be generated due to frictional contact between the roller and the take-up roller. The reason why it tends to wrap around the take-up roller is that the contact angle (wrap angle) to the take-up roller is set large in order to compensate for the poor focusing caused by not applying a sufficient amount of sizing agent, and the static electricity It is thought that this generation makes the running of pitch fibers unstable, and that the use of two take-up rollers doubles the possibility of winding. Furthermore, although the method for producing pitch fibers disclosed in JP-A-60-252722 is aimed at solving the problems of JP-A-59-1724,
In practice, it has been found that it is difficult to improve the cohesiveness of the pitch fibers and to reduce their wrapping around the take-off roller. That is, in this manufacturing method as well, a spray type is used as the sizing agent application device, which basically causes a decrease in the sizing property of the pitch fibers and causes them to wrap around the take-up roller for the same reasons as mentioned above. It is the cause. In addition, this manufacturing method uses a take-up roller whose static electricity is removed by grounding.
Since the sizing agent is applied after passing through the first take-off roller, the pitch fibers pass through the first take-off roller in a dry state, and the frictional contact with the take-off roller causes static electricity to build up. is more likely to occur, and the space between the take-up roller and pitch fibers is in a dry state, so even if the static electricity on the pick-up roller can be removed by grounding, the static electricity on the pitch fibers cannot be removed. By eliminating this, it could hardly be expected to improve the cohesiveness of the pitch fibers or reduce their winding around the take-up roller. Furthermore, two take-off rollers are still used, and the possibility of the pitch fibers getting wrapped around the take-off rollers is doubled. In addition, in this manufacturing method, in addition to using two take-up rollers, two air suction rollers are also used, and each of the two take-up rollers is equipped with a static eliminator (earth). However, there is also the problem that the entire process is quite complicated. The 6th car is also used as an air racing car.
Conventional air ejector 1 explained with reference to the figure
It was found that although the rectifying plate 6b was disposed, the rectifying effect was not sufficient, and the air flow ejected from the annular slit 4 flowed down the strand conveyance ejection passage 3a while forming a spiral flow. For this reason, the tensile force acting on the strand becomes smaller, and it is not possible to apply sufficient peeling force to the pitch fibers that are peeled off from the take-up roller, which causes the pitch fibers to become even more wrapped around the take-up roller. At the same time, the spiral flow generated in the strand transport jetting passage 3a spreads the pitch fibers of the strand, thereby further reducing its convergence. Therefore, an object of the present invention is to provide a method for manufacturing long-filament pitch fibers, which has excellent bundling properties, almost eliminates winding around a take-up roller, and simplifies the entire manufacturing process. It is. Another object of the present invention is that when long fiber pitch fibers are used in a manufacturing process, a spiral air flow is not generated in the strand conveying jet passage, and therefore a large tensile force is exerted on the strands. To provide an air ejector which can act on pitch fibers and which does not damage the convergence of pitch fibers by opening them. (Means for solving the problems) In order to achieve the above object, according to the present invention,
The raw material pitch is melt-spun into a large number of pitch fibers through a bushing, and then brought into contact with a roller-type sizing agent applicator to apply a sizing agent of about 15% or more by weight, and then passed through a sizing device to combine into one strand. The strand is passed through a take-up roller having a plurality of grooves parallel to the axis of rotation on its surface to apply a traction force, and then the strand is passed through an air ejector and stored in a container while being peeled off from the take-up roller. A method for producing long fiber pitch fibers is provided. Further, according to the present invention, in the apparatus for carrying out the method for producing long fiber pitch fibers, the air ejector has a short strand introduction passage and a downstream end is formed as a protruding tip. a protruding rear end that has a strand introduction section that is shaped like a strand, and a strand conveyance ejection passage that extends coaxially with the strand introduction passage on the downstream side thereof, and whose upstream end partially surrounds the protruding tip of the strand introduction passage; an annular manifold chamber located around an intermediate portion of the strand conveyance spout portion and having an air inlet, and an annular manifold chamber located around an upstream portion of the strand conveyance spout portion; Equipped with an adjacent buffer room,
An annular ventilate passageway is formed between the protruding tip end of the strand introduction part and the protruding rear end part of the strand conveyance spouting part, with an inlet part communicating with the buffer chamber and an outlet part facing downstream of the strand conveyance spouting passage. A long-filament Pitch fiber characterized in that a plurality of rectifier plates are arranged radially in the manifold chamber, and a plurality of communication holes are arranged in the partition wall between the buffer chamber and the manifold chamber. Manufacturing equipment is provided. (Example) Preferred embodiments of the present invention will be described below with reference to the drawings. Figures 1 and 2 show the entire process of the method for producing long fiber pitch fibers of the present invention.
Reference numeral 10 in the figure is a bushing for press-extruding and spinning a large number of pitch fibers F by heating and melting petroleum or coal-based raw material pitch. First, downstream of the bushing 10 is a roller type sizing agent applicator 11.
is located, and a concentrator 12 is located further downstream thereof. Therefore, a large number of pitch fibers F spun from the bushing 10 are brought into contact with the roller type sizing agent applicator 11 to be coated with a sizing agent, and then passed through the sizing device 12 and collected into one strand S. The roller type sizing agent application device 11 includes a drive roller 1
An endless belt 11 is placed between 1a and driven roller 11b.
The container 11d containing the sizing agent is wrapped around c.
drive roller 11a.
Dip the side belt part in the sizing agent and remove the driven roller 1.
By pressing the belt portion on the 1b side against the pitch fibers F, the sizing agent carried on the belt surface is transferred to and applied to the pitch fibers F. The drive roller 11a is actively driven by an electric motor (not shown) and its rotational speed can be adjusted, so that the amount of sizing agent applied to the pitch fibers F can be freely adjusted and a desired amount of sizing agent can be applied. It is now possible to apply
The roller-type sizing agent applicator 11 applies a sizing agent of about 15% by weight or more to the pitch fibers. The focuser 12 has a V-shaped focusing groove 12a in the center part.
It is shaped like a drum as a whole, and its surface is made of a material with a low coefficient of friction. A take-up roller 13 is located downstream of the concentrator 12, and an air ejector 14 is further downstream thereof.
and a basket 15 are arranged. Concentrator 1
The strand S made in step 2 is taken up by the take-up roller 13.
The strand S passes through contact with the strand S at a desired angle θ, and at this time a traction force is applied to the strand S. tension roller 1
Strand S passing through 3 is air ejector 14
In this process, a tensile force due to the air flow acts on the strand S, and as a result, the strand S
A peeling force is applied to the take-up roller 13, and the film is peeled off without being wrapped around the take-up roller 13. The strand S passing through the air ejector 14 is stored in a basket 15. The take-up roller 13 is actively driven at a desired rotation speed by an electric motor (not shown), thereby adjusting the spinning speed of the pitch fibers S. On the roller surface of the take-up roller 13,
Preferably, a plurality of grooves 13a are formed in parallel to the rotation axis direction of the roller, so that the strand S can be peeled off from the take-up roller with a small peeling force without weakening the traction force of the take-up roller 13. Also, the take-up roller 13
The surface of the roller is preferably treated with a resin of uniform thickness using, for example, a fluororesin.
As a result, the strand S is further removed from the take-up roller 1.
It is designed so that it can be easily peeled off from 3. According to the above configuration, first, the sizing agent coating device 11
Since I used a roller type one, belt 1
The sizing agent carried by the drive roller 1c directly contacts the pitch fibers F and is applied thereto, and the amount of the sizing agent applied increases or decreases in proportion to the belt speed.
By adjusting the rotation speed of a, the amount of sizing agent applied can be freely adjusted, which was not possible with conventional spray-type sizing agent applicators, for example.
As much as about 15% by weight or more of the sizing agent as described above can be applied. Naturally, applying such a large amount of sizing agent basically greatly helps in improving the sizing properties of the strands S. The roller type sizing agent applying device 11 is arranged so that after applying the sizing agent to a large number of pitch fibers F, the sizing agent is collected into one strand S by a sizing device 12. For this purpose, the concentrator 12
Since the strand S passing through the take-up roller 13 becomes sufficiently wet, static electricity is not generated due to frictional contact therewith, and this also greatly contributes to improving the convergence of the strand. In addition, since a sufficient amount of sizing agent is applied to the strand S as described above, when it comes into contact with the take-off roller 13, the adhesion force with it increases, and as shown in the figure, the contact angle θ with the take-off roller 13 increases. The necessary traction force can be obtained even if the traction force is not large, and because the contact angle is small, the peeling force of the strand S separating from the take-up roller is small, thereby reducing the occurrence of winding around the take-up roller. Further, according to the illustrated embodiment, the plurality of grooves 13a are provided on the roller surface of the take-up roller 13 as described above, so that the strand S can be peeled off from the roller surface with a small peeling force without affecting the traction force applied to the strand S. I'm trying to do it. Therefore,
Even if the strand S is brought into contact with the take-up roller 13 at a large contact angle in order to apply a large traction force, it can be peeled off with a relatively small peeling force.
There is almost no winding around the take-up roller. This can be further ensured by processing the roller surface with resin as described above. As a result, even if the strand S is brought into contact with the strand S at a contact angle of 360 degrees, that is, wrapped around the take-off roller once, it can be easily peeled off without winding around the take-off roller. Next, the detailed structure of the air ejector 14 used in the manufacturing process of the long fiber pitch fiber described above will be explained with reference to FIGS. 3 to 5. The air ejector 14 has a strand introduction passage 20a, and a downstream end thereof has a protruding tip 20.
Strand introduction part 20 formed as b
and a strand conveyance ejection passage 21a located downstream of and coaxially with the strand introduction passage 20a.
and the upstream end is the strand introduction part 2
A strand conveying spout portion 21 formed as a protruding rear end portion 21b partially surrounding the protruding tip portion 20b of No. 0, and an annular manifold chamber 22a located around an intermediate portion of the strand conveying spout portion 21.
and the air inlet 2 of this annular manifold chamber 22a.
2b, and a buffer chamber section 23 having a buffer chamber 23a located around the upstream portion of the strand conveying spout section 21 and adjacent to the annular manifold chamber 22a. The protruding tip portion 20b of the strand introducing portion 20 and the protruding rear end portion 21b of the strand conveyance spouting portion 21 are arranged so that an inlet portion thereof communicates with the buffer chamber 23a and an outlet portion thereof faces toward the downstream side of the strand conveyance spout passage 21a. They are spaced apart from each other to form an annular ventilate passageway 24. Manifold chamber 22a
A plurality of rectifying plates 22c are arranged radially in the buffer chamber 23a and a partition wall 25 having a plurality of communication holes 25a is arranged between the buffer chamber 23a and the manifold chamber 22a. The strand conveying spout passage 21 communicates with the manifold chamber 22a through the ventilate passage 24 and the vent passage 24.
It is connected to a. Preferably, the inner walls of the strand introduction passage 20a and the strand conveyance and ejection passage 21a are resin-processed using, for example, fluororesin. Moreover, the strand conveyance jet passage 21a is tapered so that the cross-sectional area becomes larger as it goes downstream. Also preferably, the strand introduction portion 20 is
It is configured as a movable member attached to the wall of the buffer chamber portion 23 via a screw mechanism 26, and by rotating the screw mechanism 26, the gap width of the annular ventilate passage 24 can be adjusted. There is. In the manifold portion 22, a pair of air inlets 22b are provided facing each other in the radial direction, and the rectifying plate 22c has a tapered trapezoidal shape with an inclined lower edge as shown in the figure, thereby allowing the air to flow through the air. Air introduced from the inlet 22b passes through the space below the lower edge of the rectifying plate 22c and enters the manifold chamber 2.
It is designed to be distributed throughout 2a. Since the air ejector 14 is configured in this way, the air introduced from the air introduction port 22b immediately passes through the rectifying plate 22 when it enters the manifold chamber 22a.
The flow is rectified by c, then enters the buffer chamber 23a through the communication hole 25a, where the flow is calmed down, and in that state is ejected through the annular ventilate passage 24 to the strand conveyance jet passage 21a. Due to the synergistic effect of the rectifying effect in the manifold chamber 22a and the calming effect in the buffer chamber 23a, the air ejected into the strand conveyance ejection passage 21a flows in the axial direction of the passage without almost creating a spiral flow. It becomes like this. As a result, a strong tensile force acts on the strand passing through the strand conveyance jet passage 21a, and the spiral flow does not open the pitch fibers of the strand. Therefore, by using such an air ejector 14, a large peeling force can be applied to the strand S leaving the take-up roller 13, so that the occurrence of winding around the take-up roller 13 can be further reduced. Moreover, the convergence of the strand is not impaired when passing through the air ejector 14, and the convergence can be maintained well. Further, according to this air ejector 14, since the inner walls of the strand introduction passage 20a and the strand conveyance/ejection passage 21a are treated with resin, the sizing agent carried by the strands is difficult to adhere to the inner walls. It becomes difficult for cutting debris from pitch fibers to adhere to the surface, greatly reducing contamination, and eliminating the need for periodic disassembly and cleaning, making maintenance extremely easy. In addition, because it is difficult for resistive substances such as sizing agents and cut scraps of pitch fibers to adhere to the inner wall, the air flow is not disturbed, and a stronger tensile force is applied to the strands, allowing the strands to separate from the take-up roller. Can increase power. Returning again to the overall process shown in FIGS. 1 and 2, as is clear from the above explanation, in the method for producing pitch fibers of the present invention, only one take-off roller is used. It is clear that the occurrence of winding of the pitch fibers around the take-up roller can be reduced more than when a plurality of them are used. Also, since only one air ejector is used in addition to the take-up roller,
This allows the entire manufacturing process to be extremely simplified. Experimental examples for demonstrating the effects of the present invention are shown below. Experimental Example 1-6 Long fiber pitch fibers were produced using the method shown in FIGS. 1 and 2 and according to the conditions shown in Table 1. However, the take-up roller 13 used was one with a diameter of 300 mm whose surface was not treated with resin, and in Experimental Example 1, one without grooves was used, and in Experimental Examples 2-6, one with grooves was used.
The air ejector has a structure shown in FIGS. 3 to 5, and the total length of the strand introduction part 20 and the strand conveyance jet part 21 is
133.5 mm, the diameter of the inlet of the strand introduction passage 20a was 3.2 mm, and the inner walls of the strand introduction passage 20a and the strand conveyance/ejection passage 21a were treated with fluororesin. This air ejector is indicated by a Roman numeral in the section of air ejector types in Table 1. For comparison, a non-grooved take-up roller is used and is designated by a Roman numeral as an air ejector. Experiments using the conventional one shown in Fig. 6, and Fig. 3 - represented by Roman numerals.
An experiment was conducted using the structure shown in FIG. 5 with the rectifying plate 22c removed from the manifold chamber 22a, and these were shown as Comparative Examples 1 and 2, respectively. In all experimental examples and comparative examples, the raw material pitch used was optically isotropic (iso-based) with a benzene insoluble content of 57%, and the sizing agent used was water-insoluble.
It contained 99 parts by weight and 1 part by weight of ethyl alcohol. The results of the above experimental examples and comparative examples are still the same as the first one.
Shown at the bottom of the table. Here, the results are determined by visually checking the quality of the convergence of the obtained strands, and are classified as "worst", "bad",
6: “fairly good”, “good”, “fairly good”, “best”
Shown in stages. As can be seen from the section "Amount of sizing agent applied, weight %" in Experimental Example 1-6, a large amount of sizing agent of 15% by weight or more was applied by using the roller type sizing agent coating device. Therefore, the convergence of the strands ranged from "slightly good" to "best," indicating that the convergence was sufficiently improved. In addition, especially in Experimental Example 2-6 when a grooved one was used as a take-up roller, the strand convergence was "good".
shows "best", and it can be seen that it is further improved. This is thought to be because the peeling from the take-up roller is performed smoothly and the cohesiveness of the strand is not impaired. Furthermore, from the results of Comparative Examples 1 and 2 and the results of Experimental Example 1, it can be seen that the convergence of the strands is also improved by using the air ejector shown in Figures 3 to 5. . As a result, it was confirmed that the air ejector of the present invention hardly generates a spiral air flow, therefore imparts a strong peeling force to the strands, and does not open the pitch fibers. Experimental Example 7-11 The raw material pitch and sizing agent used were Experimental Example 1-6.
However, the take-up roller used was one whose surface was treated with fluororesin. Other conditions and results are shown in Table 2. Experimental example 12-16 The raw material pitch used had a benzene insoluble content of 92.3
%, and is optically anisotropic (meso-based) with a quinoline insoluble content of 41.8%.The components of the sizing agent are 99.5 parts by weight of water and 0.5 parts by weight of surfactant. A roller with the same fluororesin surface treatment as in -11 was used. Other conditions and results are also shown in Table 2. In Experimental Examples 7-11 and 12-16, the convergence of the strands was "fairly good" or "best", indicating that the convergence was significantly improved. This is because the take-up roller is treated with fluororesin.
This is because the strands can now be peeled off from the take-up roller with a smaller force, and as shown in the section "Air ejector air flow rate", this is due to the fact that the strands can be peeled off from the take-up roller with a smaller force compared to Experimental Example 1-6. This can be seen from the fact that the air flow rate of the air ejector can be reduced by about 40%.

【table】

【table】

[Table] (Effects of the Invention) As is clear from the above, according to the method for producing long-filament pitch fibers of the present invention, it is possible to significantly improve the bundling of pitch fibers in the strand, and the strands to the take-up roller It is less likely that the material will become wrapped around the material, and the manufacturing process can be simplified. Furthermore, according to the air ejector of the present invention, almost no spiral air flow is generated, and a large pulling force can be applied to the strand, thus imparting a large peeling force to the strand as it leaves the take-up roller. It is possible to reduce the occurrence of winding and maintain convergence, and also to maintain convergence without opening the pitch fibers in the air ejector.

[Brief explanation of drawings]

FIG. 1 is a schematic side view of the manufacturing process showing an example of the method for manufacturing long fiber pitch fibers according to the present invention, and FIG. 2 is a schematic front view of the manufacturing process shown in FIG. 3 is a longitudinal sectional view of the air ejector used in the manufacturing process shown in FIG. 1, FIG. 4 is a sectional view taken along the - line in FIG. 3, and FIG. FIG. 6 is a longitudinal cross-sectional view of a conventional air ejector. In the figure, reference numerals 10...bushing, 11...roller type sizing agent applicator, 12...concentrator, 13...
Take-up roller, 13a...Groove, 14...Air ejector, 15...Basket (container), 20
... Strand introduction part, 20a ... Strand introduction passage, 20b ... Projection tip, 21 ... Strand transport jetting section, 21a ... Strand transport jetting passage, 21b ... Projection rear end, 22 ... Manifold part, 22a...manifold chamber, 22b...
... Air inlet, 22c... Current plate, 23... Buffer chamber portion, 23a... Buffer chamber, 24... Annular ventilate passage, 25... Partition wall, 25a... Communication hole.

Claims (1)

[Scope of Claims] 1 The raw pitch is melt-spun into a large number of pitch fibers through a bushing, and the fibers are brought into contact with a roller-type sizing agent applicator to apply a sizing agent of about 15% by weight or more, and then passed through a sizing device. The strand is assembled into a single strand, passed through a take-up roller whose surface has a plurality of grooves parallel to the axis of rotation to apply traction, and then passed through an air ejector to be peeled off from the take-up roller while being removed from the container. 1. A method for producing long-filament pitch fibers, characterized in that the fibers are accommodated in a container. 2. The manufacturing method according to claim 1, wherein the take-up roller uses a roller whose surface is treated with resin. 3. The manufacturing method according to claim 1, wherein the air ejector is one that hardly generates a spiral air flow. 4 The raw material pitch is melt-spun into a large number of pitch fibers through bushings, brought into contact with a roller-type sizing agent applicator to apply a sizing agent, passed through a sizing device to gather into one strand, and the strand is taken up by a roller. In an apparatus for manufacturing long-filament pitch fibers, the strand is passed through an air ejector to apply a traction force, and then the strand is stored in a container while being peeled off from a take-up roller.
The air ejector includes a strand introduction portion having a short strand introduction passage and whose downstream end is formed as a protruding tip, and a strand conveying jet extending coaxially with the strand introduction passage downstream of the strand introduction passage. A strand conveying spout portion having a passage and an upstream end formed as a protruding rear end portion partially surrounding the protruding tip portion of the strand introducing portion; and a strand conveying spout portion located around an intermediate portion of the strand conveying spout portion. an annular manifold chamber having an air inlet; and a buffer chamber located around the upstream portion of the strand conveyance spout portion and adjacent to the annular manifold chamber, An annular ventilate passageway is formed between the projecting rear end part and the inlet part communicates with the buffer chamber and the outlet part faces downstream of the strand conveyance and jetting passage, and a plurality of rectifier plates are arranged radially in the manifold chamber. 1. An apparatus for producing long fiber pitch fibers, characterized in that a plurality of communicating holes are arranged in a partition wall between a buffer chamber and a manifold chamber. 5. The manufacturing apparatus according to claim 4, wherein the inner walls of the strand introduction passage and the strand conveyance and ejection passage are processed with resin. 6. The manufacturing apparatus according to claim 4, wherein the strand conveyance and ejection passage has a tapered shape such that the cross-sectional area becomes larger as it goes downstream.