JP4829865B2 - Manufacturing method of long fiber reinforced thermoplastic resin pellets - Google Patents

Description

  The present invention relates to a method for producing a twisted long fiber reinforced thermoplastic resin pellet using a reinforcing fiber bundle continuously drawn from a wound body.

  Long fiber reinforced thermoplastic resin pellets (hereinafter also simply referred to as long fiber reinforced resin pellets) are used as raw materials for injection molding. The long fiber reinforced resin pellet has excellent mechanical strength compared to the short fiber reinforced resin pellet because the pellet length (for example, about 3 to 10 mm) is almost the same as the fiber length.

  For the production of long fiber reinforced resin pellets, a wound body (roving package) formed by winding a reinforcing fiber bundle (roving) formed by bundling a large number of reinforcing single fibers (filaments) is used. And as a manufacturing method of this long fiber reinforced resin pellet, the drawing method which does not twist, and the drawing method which performs twist are known.

  The drawing method without twisting is to continuously introduce the reinforcing fiber bundle drawn from the wound body into the impregnation die, impregnate the reinforcing fiber bundle with the molten thermoplastic resin, and impregnate the resin from this impregnation die. In this method, long fiber reinforced resin strands composed of reinforcing fiber bundles are continuously taken out, and the long fiber reinforced resin strands are cut into a predetermined length to produce long fiber reinforced resin pellets. FIG. 6 is a schematic diagram showing long fiber reinforced resin pellets obtained by a drawing method without twisting.

  Further, the drawing method for twisting is performed by continuously introducing the reinforcing fiber bundle drawn from the wound body into the impregnation die, impregnating the molten fiber bundle with the molten thermoplastic resin, and downstream of the impregnation die. From the resin-impregnated reinforcing fiber bundle to which the twist is applied to the resin-impregnated reinforcing fiber bundle continuously passing through the impregnation die by a twisting machine such as a twisting roller provided on the side, and the twist is applied from the impregnation die The long fiber reinforced resin strand is continuously taken out, and the long fiber reinforced resin strand is cut into a predetermined length to produce a long fiber reinforced resin pellet. FIG. 5 is a schematic view showing long fiber reinforced resin pellets obtained by a drawing method for twisting.

  By the way, when a long fiber reinforced resin pellet is manufactured using a reinforcing fiber bundle continuously drawn from the wound body, the reinforcing fiber bundle of the wound body after use and the reinforcing fiber of the new wound body are used. It is necessary to join the bundles so that the reinforcing fiber bundles can be continuously supplied over a long period of time.

  Japanese Patent Laid-Open No. 6-114832 discloses that when producing a long fiber reinforced resin pellet by the above-described drawing method without twisting, the end portion of the reinforcing fiber bundle of the end-of-use wound body and a new wound body The reinforcing fiber bundle of the end-of-use winding and the reinforcing fiber bundle of the new winding are formed by superimposing the reinforcing fiber bundle on the first end portion and interlacing the overlapped portions with an air splicer. There has been proposed a method for producing long fiber reinforced resin pellets that are joined together (first prior art).

  However, in the first prior art described above, the amount of fibers in the joint portion (seam) between the reinforcing fiber bundle of the end-of-use wound body and the reinforcing fiber bundle of the new wound body is the amount of the reinforcing fiber bundle. The fiber amount is doubled, and the thickness of the spliced portion becomes larger than the thickness of the original reinforcing fiber bundle. For this reason, when producing a long fiber reinforced resin pellet having a fiber content of about 30% or more, the joining portion is easily caught by the die nozzle of the impregnation die, and the reinforcing fiber bundle is easily disconnected at a high production speed. There's a problem.

  Japanese Patent Application Laid-Open No. 2003-301340 proposes a method for joining fiber bundles together (second prior art). Each fiber bundle is formed by bundling a large number of single fibers (filaments). FIG. 7 is a schematic diagram for explaining the second prior art.

  The method according to the second prior art will be described. As shown in FIG. 7, after one fiber bundle X1 and the other fiber bundle X2 are aligned so as to overlap each other, the fiber bundle X1 is halved to form a yarn Y1 ′ and a yarn Y1. Further, the fiber bundle X2 is halved to form the yarn Y2 and the yarn Y2 ′. Next, the yarn Y1 ′ and the yarn Y2 are overlapped, and the yarn Y1 and the yarn Y2 ′ are overlapped. Then, with the air splicer, Y1 ′ and Y2 are entangled to form the entangled portion Z1, and Y1 and Y2 ′ are entangled to form the entangled portion Z2. In this case, the entangled portions Z1 and Z2 are formed at different positions in the fiber bundle longitudinal direction.

However, in the second prior art described above, the amount of fibers in the (Z1 + Y1) portion composed of the entangled portion Z1 and the yarn Y1 is 1.5 times the amount of fibers in the fiber bundle X1, and the thickness of the (Z1 + Y1) portion is It becomes larger than the thickness of the original fiber bundle X1. Similarly, the amount of fibers in the (Z2 + Y2) portion composed of the entangled portion Z2 and the yarn Y2 is 1.5 times the amount of fibers in the fiber bundle X2, and the thickness of the (Z2 + Y2) portion is that of the original fiber bundle X + 2. It becomes larger than the thickness. For this reason, when a long fiber reinforced resin pellet having a high fiber content is manufactured using the reinforcing fiber bundle spliced by the second conventional technique, the splicing having the (Z1 + Y1) portion and the (Z2 + Y2) portion. There is a problem that the portion is easily caught by the die nozzle of the impregnation die.
Japanese Patent Laid-Open No. 6-114732 (paragraph [0009]) JP 2003-301340 A (paragraph [0011], FIG. 1)

  Therefore, the object of the present invention is to use a reinforcing fiber bundle that is continuously drawn from a wound body, and to produce a long fiber reinforced thermoplastic resin pellet by a twisting method for twisting. The joint portion between the reinforcing fiber bundle of the body and the reinforcing fiber bundle of the new wound body can be passed through the die nozzle of the impregnation die at a high production rate without causing disconnection of the reinforcing fiber bundle. An object of the present invention is to provide a method for producing a long fiber reinforced thermoplastic resin pellet.

  In order to solve the above problems, the present invention takes the following technical means.

  According to the first aspect of the present invention, the reinforcing fiber bundle drawn from the wound body is continuously introduced into the impregnation die, the molten fiber bundle is impregnated with the molten thermoplastic resin, and the downstream side of the impregnation die A long fiber comprising a resin-impregnated reinforcing fiber bundle to which a twist is imparted to the resin-impregnated reinforcing fiber bundle continuously passing through the impregnation die by a twisting machine provided on the impregnation die In the method of continuously taking up the reinforced resin strands and pelletizing the long fiber reinforced resin strands to produce the long fiber reinforced thermoplastic resin pellets, the end portion of the reinforcing fiber bundle of the end-of-use wound body and a new winding For both the body reinforcing fiber bundle and the starting end part, respectively, a part of the reinforcing fiber bundle is removed to form a fiber amount half-end portion of which the fiber amount is about half of the original amount. The fiber amount half-ends are entangled at one or more places in the longitudinal direction, and further, at one or more places in the longitudinal direction in the fiber amount non-reducing end portion following the fiber half-end part in the new wound body Then, by reinforcing the reinforcing fibers with the air splicer, the reinforcing fiber bundle of the end-of-use wound body and the reinforcing fiber bundle of the new wound body are joined together, and the reinforcing fiber bundle is continuous. It is a manufacturing method of the long fiber reinforced thermoplastic resin pellet characterized by supplying.

  According to a second aspect of the present invention, in the method for producing a long fiber reinforced thermoplastic resin pellet according to the first aspect, an adhesive is further applied to the entangled portion entangled by an air splicer, and a reinforcing fiber bundle is used as the adhesive. The same resin as the thermoplastic resin to be impregnated is used.

  According to the method of the present invention, when a long fiber reinforced thermoplastic resin pellet is produced by a drawing method in which twisting is performed using a reinforcing fiber bundle continuously drawn from the wound body, the wound body is used up. The joint portion between the reinforcing fiber bundle and the reinforcing fiber bundle of the new wound body is cut off of the reinforcing fiber bundle or the clogging of the fluff to the die nozzle that will cause the production stop after passing through the die nozzle of the joint portion. Without causing any problems, the die nozzle of the impregnation die can be passed at a high production rate, and the productivity of the long fiber reinforced thermoplastic resin pellets can be improved.

  FIG. 1 is a diagram showing a configuration of a long fiber reinforced thermoplastic resin pellet manufacturing apparatus for carrying out the manufacturing method of the present invention.

  As shown in FIG. 1, the reinforcing fiber bundle 2 drawn out from the wound body 1 is provided with a pair of heating rollers 6A and 6B in which a plurality (three in the example of FIG. 1) are aligned. It is led to the preheating heating device 5. The reinforcing fiber bundle 2 is guided into the impregnation die 7 while being heated by the preheating heating device 5. The impregnation die 7 is continuously supplied with a molten resin (molten thermoplastic resin) 3 from an extruder 10 incorporating a screw 11. In the impregnation die 7, a plurality of impregnation rollers 9 for impregnating the reinforcing fiber bundle 2 with the molten resin 3 are arranged. A die nozzle 8 is attached to the outlet of the impregnation die 7 to determine the wire diameter of the long fiber reinforced resin strand 4 having a circular cross section made of a fiber bundle for reinforcing resin impregnation with a twist.

  The reinforcing fiber bundle 2 is impregnated with the molten resin while passing through the impregnation die 7 to form a resin impregnated reinforcing fiber bundle. The resin impregnated reinforcing fiber bundle is twisted by twisting rollers 13A and 13B as twisting machines provided on the downstream side of the impregnation die 7. And the long fiber reinforced resin strand 4 which consists of the fiber bundle for resin impregnation reinforcement | strengthening to which twist was provided is continuously taken out from the impregnation die | dye 7 by the twist rollers 13A and 13B.

  The high-temperature long fiber reinforced resin strand 4 drawn from the die nozzle 8 of the impregnation die 7 is cooled and hardened by the cooling water tank 12 and guided to the twisting rollers 13A and 13B. Then, the long fiber reinforced resin strand 4 guided to the downstream side of the twisting rollers 13A and 13B is cut into a predetermined length by the pelletizer 14 to be a long fiber reinforced resin pellet.

  2 is an explanatory diagram of the twisting roller shown in FIG. 1, and FIG. 3 is a diagram for explaining the twisting angle of the twisting roller shown in FIG.

  As shown in FIG. 2, the pair of twisting rollers 13A and 13B holds the respective rotation axes on parallel planes (horizontal planes), and reinforced long fibers from the upstream side in a state where the rotation axes intersect each other. The resin strands 4 are arranged so as to face each other. That is, the rotation axis of the upper twisting roller 13A and the rotation axis of the lower twisting roller 13B in FIG. 2 are opposite to each other in the direction opposite to the take-up direction of the long fiber reinforced resin strand 4 in plan view. The angle is set to be deviated by a predetermined angle (twisting angle θ).

  As shown in FIG. 3, the twisting angle θ of the twisting roller 13A is an angle formed by a line perpendicular to the rotational axis a of the twisting roller 13A and the take-up direction of the long fiber reinforced resin strand 4 in plan view. The twist angle of the lower twist roller 13B is the same as the twist angle θ of the upper twist roller 13A.

  By the way, as a method of pulling out (feeding out) the reinforcing fiber bundle from the wound body, there are an outside method and an inside method. The outside method is a method of pulling out the reinforcing fiber bundle from the outer peripheral side of the wound body while rotating the wound body. On the other hand, the internal arrangement method is a method in which the reinforcing fiber bundle is pulled out from the circumferential side of the wound body with the wound body placed on a certain object. There is also a method of pulling out the reinforcing fiber bundle from the outer periphery side of the wound body with the wound body placed on a certain object. In the manufacturing apparatus shown in FIG. 1, the wound body 1 is a wound body obtained by winding up the reinforcing fiber bundle 2 in an uncentered cylindrical shape, and the reinforcing fiber bundle 2 is pulled out from the inner peripheral side of the wound body 1. Employs the interior method.

  FIG. 4 is a diagram for explaining the production method according to the present invention, and is a schematic diagram for explaining a method for joining reinforcing fiber bundles together.

  In the production method of the present invention, when joining the reinforcing fiber bundle A of the end-of-use wound body and the reinforcing fiber bundle B of the new wound body, at the end portion of the reinforcing fiber bundle A on the end-of-use side Then, a part of the reinforcing fiber bundle A is cut off with scissors or the like to form a fiber amount half-end A1 having a predetermined length with a fiber amount approximately half of the original. Further, at the starting end portion of the new-side reinforcing fiber bundle B, a part of the reinforcing fiber bundle B is cut off with scissors or the like, and the fiber amount half-end B1 of a predetermined length whose fiber amount is about half of the original length. Form. In addition, the length of fiber amount half-end part A1, B1 is the range of about 50-150 mm. The lengths of the fiber amount half-ends A1 and B1 are about 50 mm in the case of reinforcing fibers that are easy to be entangled, and about 100 to 150 mm in the case of reinforcing fibers that are difficult to be entangled.

  Next, both the fiber half-ends A1 and B1 are arranged so as to overlap each other, and the fiber half-ends A1 and B1 are entangled at one or more places in the longitudinal direction by an air splicer. C1 is formed. In the example of FIG. 4, the entangled part C1 is formed in two places. Therefore, the fiber amount of the entangled portion C1 is substantially the same as the original fiber amount (original fiber amount) of the reinforcing fiber bundles A and B, and the thickness of the seam between the fiber amount half-end portions A1 and B1 is reinforced. The fiber bundles A and B can be made substantially the same as the thickness.

  Further, at the fiber non-reducing end (the original reinforcing fiber bundle part not reducing the fiber amount) B2 following the fiber half half end B1 on the new side, reinforced by an air splicer at one or more points in the longitudinal direction. The fibers for use are entangled to form an entangled portion C2. In the example of FIG. 4, the entanglement part C2 is formed in two places. By forming the entangled portion C2, it is possible to prevent the reinforcing fiber of the fiber amount non-reduced end B2 from being scattered during the introduction to the impregnation die and to prevent the joint portion from being cut. Moreover, the thickness of the entangled portion C2 is substantially the same as the thickness of the reinforcing fiber bundles A and B. The fiber amount non-reduced end A2 following the end-of-use fiber amount half-end A1 is pulled from the impregnation die while being twisted, so that it will be caught by the die nozzle even if pulled from the downstream side. There is no. Therefore, it is not necessary to form an entangled portion at the fiber amount non-reduced end A2. After entanglement by the air splicer, the reinforcing fiber bundle B on the new side is separated from the reinforcing fiber portion (indicated by reference numerals X and Y in FIG. 4) so that it does not catch on the die nozzle. Therefore, remove with scissors. Note that, instead of cutting, the reinforcing fiber portions X and Y in which the separation occurs are bonded and fixed using an adhesive made of the same type of resin as the thermoplastic resin impregnated in the reinforcing fiber bundles A and B. You may make it do.

  In this way, the entangled portion C1 and the entangled portion C2 are formed by the air splicer in the joint portion, and the reinforcing fiber bundle A on the end-of-use side and the reinforcing fiber bundle B on the new side are made thicker. The reinforcing fiber bundles A and B are spliced so as to be approximately the same in thickness. Therefore, the joining portion is not caught by the die nozzle. Therefore, the joining portion can be passed through the die nozzle at a high production rate without causing disconnection of the reinforcing fiber bundle.

  In addition, the entangled portion C2 is formed at the fiber amount non-reducing end portion B2 of the reinforcing fiber bundle B on the new side at the joining portion. Therefore, the fiber portion non-reducing end portion B2 is not broken and the spliced portion is not cut off while the spliced portion is guided to the impregnation die through the bent pass line. Therefore, the joining portion can be passed through the die nozzle at a high production speed without causing a situation that the reinforcing fiber bundle B on the new side does not reach the impregnation die.

  In addition, the fiber bundle for reinforcing resin impregnation is pulled out from the die nozzle while being twisted by a drawing method for performing twisting. Therefore, the fluff generated when the splicing part passes through the die nozzle can be pulled out from the die nozzle. Therefore, after passing through the die nozzle of the joining portion, there is no possibility of causing a production stop due to clogging of the fuzz to the die nozzle.

  When joining the reinforcing fiber bundles in the production method of the present invention, the same resin as the thermoplastic resin impregnated in the reinforcing fiber bundles A and B is applied to the entangled portions C1 and C2 as an adhesive. You may do it. Thereby, the die nozzle can be passed through the die nozzle at a high production speed without causing the disconnection of the reinforcing fiber bundle and the like more reliably.

  Next, examples of the present invention will be described. Using the reinforcing fiber bundle in which the seam portion was formed, a production experiment of long fiber reinforced resin pellets was performed using the manufacturing apparatus shown in FIG. 1, and the method for joining the reinforcing fiber bundles was evaluated. A glass fiber bundle was used as the reinforcing fiber bundle. The composition of the glass fiber bundle per one is a glass fiber diameter (filament diameter) of 17 μm and a weight of 2400 g / km.

  [Example 1] Experimental conditions were: glass fiber bundle: 3, production rate (take-off rate): 80 m / min, thermoplastic resin: polypropylene, fiber content: about 70%, twist angle θ of the twisting roller (FIG. 3) Reference): 17.5 °. The splicing method is such that the length of the fiber half-ends A1 and B1 is about 150 mm, the fiber half-ends A1 and B1 are formed with four interlaced parts, and the fiber side non-reducing end B2 on the new side. About, it was set as the method of forming one place entanglement part. For each experiment, one of the three glass fiber bundles was spliced by the above method. Experiments using these three glass fiber bundles were carried out 10 times.

  As a result, the joint part passed through the die nozzle in all 10 times. Fluff generated when the splicing portion passes through the die nozzle was pulled out while being twisted from the die nozzle. As a result, even after passing through the die nozzle of the spliced portion, it was possible to continue to produce the long fiber reinforced resin pellets satisfactorily.

  [Example 2] The experimental conditions were: glass fiber bundle: 3, production speed (take-off speed): 80 m / min, thermoplastic resin: polypropylene, fiber content: about 70%, twist angle θ of twisting roller: 17. The angle was 5 °. The splicing method is such that the length of the fiber half-ends A1 and B1 is about 150 mm, the fiber half-ends A1 and B1 are formed with four interlaced parts, and the fiber side non-reducing end B2 on the new side. In the method, one entangled portion was formed, and a liquid polypropylene resin as an adhesive was applied to the four entangled portions in the form of a thin film and cured. For each experiment, one of the three glass fiber bundles was spliced by the above method. Experiments using these three glass fiber bundles were carried out 10 times.

  As a result, in the same manner as in Example 1, the splicing part passes through the die nozzle after all 10 times, and after the die nozzle of the splicing part passes through, the continuous fiber reinforced resin pellets are manufactured satisfactorily. I was able to.

  [Comparative Example 1] The experimental conditions were: glass fiber bundle: 3, production rate: 5 m / min, thermoplastic resin: polypropylene, fiber content: about 70%, twist angle θ of twisting roller: 17.5 ° . The joining method was a method in which the ends of the glass fiber bundles to be joined were entangled with an air splicer with the same thickness. For each experiment, one of the three glass fiber bundles was spliced by the above method. Experiments using these three glass fiber bundles were performed four times.

  As a result, the splicing part passed through the die nozzle in two of the four experiments. Disconnection occurred in the remaining two times. Even when the splicing part passes through the die nozzle, a large amount of fluff is present in the die nozzle, that is, in any of the two experiments, the production cannot be continued after the splicing part has passed through the die nozzle.

  [Comparative Example 2] The experimental conditions were: 3 glass fiber bundles, production rate: 80 m / min, thermoplastic resin: polypropylene, fiber content: about 70%, twist angle θ of twisting roller: 17.5 ° . The splicing method is such that the length of the fiber half-ends A1 and B1 is about 150 mm, the fiber half-ends A1 and B1 are formed with four interlaced parts, and the fiber side non-reducing end B2 on the new side. The method of not forming the entangled part was used. For each experiment, one of the three glass fiber bundles was spliced by the above method. Experiments using these three glass fiber bundles were performed three times.

  As a result, in the middle of the three times, while the spliced part was led to the impregnation die through the pass line, the fiber side non-reducing end B2 on the new side was scattered and the spliced part was cut. .

  [Comparative Example 3] The experimental conditions were: glass fiber bundle: 1, production rate: 10 m / min, thermoplastic resin: polypropylene, fiber content: about 30%, twist angle θ of twisting roller: 0 ° (no twist) It was. The splicing method is such that the length of the fiber half-ends A1 and B1 is about 150 mm, the fiber half-ends A1 and B1 are formed with four interlaced parts, and the fiber side non-reducing end B2 on the new side. About, it was set as the method of forming one place entanglement part. In each experiment, one glass fiber bundle was spliced by the above method. Experiments using these glass fiber bundles were performed three times.

  As a result, the joint portion passed through the die nozzle after all three times. However, a large amount of fluff in the die nozzle, that is, in any of the three experiments, the production could not be continued after passing through the die nozzle in the joint portion.

  [Comparative Example 4] The experimental conditions were: glass fiber bundle: 1, production rate: 10 m / min, thermoplastic resin: polypropylene, fiber content: about 30%, twist angle θ of twisting roller: 0 ° (no twist) It was. The splicing method is such that the length of the fiber half-ends A1 and B1 is about 150 mm, the fiber half-ends A1 and B1 are formed with four interlaced parts, and the fiber side non-reducing end B2 on the new side. The method of not forming the entangled part was used. In each experiment, one glass fiber bundle was spliced by the above method. Experiments using these glass fiber bundles were performed three times.

  As a result, in the middle of the three times, while the spliced part was led to the impregnation die through the pass line, the fiber side non-reducing end B2 on the new side was scattered and the spliced part was cut. .

  [Comparative Example 5] The experimental conditions were: glass fiber bundle: 2, production rate: 5 m / min, thermoplastic resin: polypropylene, fiber content: about 50%, twist angle θ of twisting roller: 0 ° (no twist) It was. The splicing method is such that the length of the fiber half-ends A1 and B1 is about 150 mm, the fiber half-ends A1 and B1 are formed with four interlaced parts, and the fiber side non-reducing end B2 on the new side. About, it was set as the method of forming one place entanglement part. For each experiment, one of the two glass fiber bundles was spliced by the above method. Experiments using these two glass fiber bundles were performed three times.

  As a result, the joint portion passed through the die nozzle after all three times. However, a large amount of fluff in the die nozzle, that is, in any of the three experiments, the production could not be continued after passing through the die nozzle in the joint portion.

  [Comparative Example 6] The experimental conditions were: glass fiber bundle: 3, production rate: 5 m / min, thermoplastic resin: polypropylene, fiber content: about 70%, twist angle θ of twisting roller: 0 ° (no twist) It was. The splicing method is such that the length of the fiber half-ends A1 and B1 is about 150 mm, the fiber half-ends A1 and B1 are formed with four interlaced parts, and the fiber side non-reducing end B2 on the new side. About, it was set as the method of forming one place entanglement part. For each experiment, one of the three glass fiber bundles was spliced by the above method. Experiments using these three glass fiber bundles were performed three times.

  As a result, the joint portion passed through the die nozzle after all three times. However, a large amount of fluff in the die nozzle, that is, in any of the three experiments, the production could not be continued after passing through the die nozzle in the joint portion.

It is a figure which shows the structure of the manufacturing apparatus of the long fiber reinforced thermoplastic resin pellet for enforcing the manufacturing method of this invention. It is explanatory drawing of the twist roller shown in FIG. It is a figure for demonstrating the twist angle of the twist roller shown in FIG. It is a figure for demonstrating the manufacturing method by this invention, Comprising: It is a schematic diagram for demonstrating the method of splicing reinforcement fiber bundles. It is a schematic diagram which shows the long fiber reinforced resin pellet obtained by the drawing method which performs twisting. It is a schematic diagram which shows the long fiber reinforced resin pellet obtained by the drawing method which does not twist. It is a schematic diagram for demonstrating the 2nd prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Rolled body 2 ... Reinforcing fiber bundle 3 ... Molten resin 4 ... Long fiber reinforced resin strand 5 ... Preheating heating device 6A, 6B ... Heating roller 7 ... Impregnation die 8 ... Die nozzle 9 ... Impregnation roller 10 ... Extruder DESCRIPTION OF SYMBOLS 11 ... Screw 12 ... Cooling water tank 13A, 13B ... Twist roller 14 ... Pelletizer A, B ... Reinforcing fiber bundle A1, B1 ... Fiber amount half end A2, B2 ... Fiber amount non-reduced end C1, C2 ... Interlaced part

Claims (2)

The reinforcing fiber bundle drawn from the wound body is continuously introduced into the impregnation die and impregnated with the molten thermoplastic resin in the reinforcing fiber bundle, and by a twister provided on the downstream side of the impregnation die The fiber-impregnated reinforcing fiber bundle passing continuously through the impregnation die is twisted, and the continuous fiber-reinforced resin strand composed of the resin impregnated reinforcing fiber bundle to which the twist is applied from the impregnation die is continuously provided. In a method for producing a long fiber reinforced thermoplastic resin pellet by taking, pelletizing the long fiber reinforced resin strand,
For both the end portion of the reinforcing fiber bundle of the end-of-use wound body and the beginning end portion of the reinforcing fiber bundle of the new wound body, a part of the reinforcing fiber bundle is removed to obtain the original fiber amount. A half-end portion of the fiber amount that is about half is formed, and the half-end portion of the fiber amount is entangled at one or more places in the longitudinal direction by an air splicer, and further, the half-end portion of the fiber amount in the new wound body In the non-reducing end portion of the fiber amount, the reinforcing fiber bundle of the end-of-use wound body and the new winding are entangled with each other by an air splicer at one or more locations in the longitudinal direction. A method for producing a long fiber reinforced thermoplastic resin pellet, comprising joining a body reinforcing fiber bundle and continuously supplying the reinforcing fiber bundle. The long fiber according to claim 1, wherein an adhesive is further applied to the entangled portion entangled by an air splicer, and the same resin as the thermoplastic resin impregnated in the reinforcing fiber bundle is used as the adhesive. A method for producing reinforced thermoplastic resin pellets.

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