JP5540722B2 - Prepreg manufacturing apparatus and manufacturing method - Google Patents

Description

  The present invention relates to an apparatus and a method for manufacturing a prepreg that is a composite material of a reinforcing fiber and a synthetic resin.

  BACKGROUND ART Fiber composite materials obtained by combining reinforced fibers such as carbon fibers, glass fibers, and aramid fibers and various matrix resins are widely used in aerospace and general industrial fields. These fiber composite materials are excellent in mechanical properties, dimensional stability, heat resistance, chemical resistance, weather resistance, and the like. Among these, carbon fiber composite materials are widely used in automotive parts and the like because of their excellent mechanical properties and light weight.

  As the matrix resin, a thermosetting resin such as an epoxy resin, a polyimide resin, or an unsaturated polyester resin is mainly used, but a thermoplastic resin may be used. A prepreg using a thermoplastic resin as a matrix resin has features such as excellent impact resistance, easy storage of the prepreg, further shortening molding time and reducing molding cost.

  As a prepreg manufacturing method using a thermoplastic resin as a matrix resin, a film-like resin is heated and melted to impregnate reinforcing fibers (melt impregnation method), and a powdered resin is reinforced by a fluidized bed method or suspension method. A method of applying and fusing to a fiber (powder method), a method of making a resin into a solution, and removing the solvent after impregnating the reinforcing fiber (solution impregnation method) are known. However, in the melt impregnation method, since the melt viscosity of the resin is high, it is difficult to impregnate the resin uniformly into the carbon fiber. In the powder method, it is difficult to adjust the amount of impregnation of the resin, and in the solution impregnation method, there are problems that the types of resins and solvents that can be used are limited.

  As a prepreg that is an intermediate material of a fiber composite material, a high-quality spread prepreg in which constituent fibers are arranged in parallel and uniformly as much as possible is required. Thermoplastic resins typified by polypropylene and polyamide have a high viscosity compared to the viscosity before thermosetting a thermosetting resin such as an epoxy resin even in a heat-melted state. There is still room for improvement in the uniform impregnation of the resin.

  Patent Documents 1 and 2 describe a method of manufacturing a spread prepreg in which fibers are parallel, thin overall, and the fiber distribution density is continuously uniform.

  However, when trying to open a plurality of bundles by these methods, there is a problem that a good prepreg cannot be obtained. This is considered to be caused by the fact that the flow of airflow is not constant between the case of a single reinforcing fiber bundle and the case of multiple fibers because the airflow that is a fluid is allowed to pass during opening. .

  In Patent Documents 3 to 8, fiber opening by providing an angle between the rollers (Patent Document 3), fiber opening by tapping the fiber and adjusting the tension (Patent Document 4), and the roller in the traveling direction. Opening by a roller such as opening by vibrating in the vertical direction (Patent Document 5), opening by descending airflow (Patent Document 6), opening by water flow (Patent Document 7), etc., Opening by ultrasonic vibration (Patent Document 8) is described.

  However, in any of the methods, there is a problem that the carbon fiber is damaged or fuzzed when the reinforcing fiber is opened, or the carbon fiber is not sufficiently opened and is not quantitative.

  In Patent Document 9, a thermoplastic resin powder is dispersed in an organic solvent such as alcohol or a mixed solvent of an organic solvent and water to form a suspension, and a strand or sheet of carbon fiber is immersed in the suspension, and the resin powder is used as a strand or A method is described in which a thermoplastic resin and carbon fiber strands or sheets are integrated by heating them after they are attached to a sheet to melt the resin. According to Patent Document 9, according to this method, a prepreg in which a resin is impregnated relatively uniformly can be obtained (variation value of impregnated resin amount is 4.2 to 5.0). (The variation value of the amount of impregnated resin is 2.8 to 3.8). However, since this method uses a solvent, a post-process such as a solvent treatment is required.

  Patent Document 10 discloses a fiber opening means for performing fiber opening and widening by bending a plurality of fiber bundles at a predetermined angle on a plurality of fixed rollers and passing under tension, and a rotating body of a resin-impregnated portion. A plurality of drum-shaped scissors rollers are arranged between the two, supplying a fiber sheet, and opening the rotating body at a surface speed higher than the traveling speed of the fiber sheet. Have been described. Here, the traveling speed of the sheet-like material is a take-up speed when the fiber sheet provided with resin in the resin-impregnated portion is taken up by a take-up roller.

  In this method, a fixed roller is used as the opening means, and the surface of the method is preferably a slide that has been subjected to a composite plating treatment in which fine particles of a fluororesin are dispersed in an electroless nickel coating. It is considered that the fiber is opened while suppressing friction between the roller and the fiber bundle as much as possible, and it is mainly the tension that is involved in the fiber opening, so that the fiber opening is insufficient.

  In Patent Document 11, the center axis is disposed between the fiber opening means and the resin impregnated portion in a direction intersecting the reinforcing fiber sheet, and rotates at the peripheral speed Vr in the same direction as the conveying direction of the reinforcing fiber sheet. Is described, and the relationship between the circumferential speed Vr and the conveying speed Vf is set to 0 <Vr / Vf ≦ 0.9, thereby eliminating the meandering and gaps of the reinforcing fibers in the fiber opening and widening. Therefore, there is a description that quality is improved when processed into a prepreg. In this method, since the fibers having disordered orientation are generated in the fiber opening means, the tension of the fiber bundle containing the disordered single fibers is relaxed, and the disorder of orientation is improved by contact with the drive roller and rubbing. .

  In Patent Document 11, the reinforcing fiber bundle is first opened and then brought into contact with a driving roller whose peripheral speed is lower than the conveying speed in order to eliminate meandering and gaps. However, it is difficult to use a driving roller that adjusts the fiber flow disturbed in the fiber-spreading process, even if a driving roller with adjusted peripheral speed is used. Because of contact, there is a problem that cutting and fluffing are likely to occur.

  In Patent Document 12, in a manufacturing apparatus and a manufacturing method for glass long fiber pellets, a pair of upstream rollers (driving rollers) sandwiching the fibers on the upstream side from the opening portion, and fibers positioned on the downstream side from the resin impregnation portion. It describes that a pair of downstream rollers (feed rollers) sandwiching the roller is provided, and the rotational peripheral speeds of the upstream roller and the downstream roller are made equal. An impregnation roller is installed between the upstream roller (drive roller) and the downstream roller (feed roller). The impregnation roller opens fibers and impregnates glass fibers with molten resin, does not include a drive mechanism, and rotates with the flow of the fibers. Therefore, almost no tension is applied to the fiber at the opening portion and the resin impregnation portion between the upstream roller and the downstream roller. As a result, the glass fibers can be easily opened, and a long amount of resin can be impregnated into the glass fibers.

  However, in such a method, there are cases where the gaps are too large, the gaps cannot be made uniform, or the resin is excessively impregnated and voids are generated.

  Patent Document 13 describes that a control plate that suppresses resin accumulation is provided in order to prevent generation of fluff due to resin dripping or the like in the resin-impregnated portion, or poor thickness accuracy. However, although this method suppresses resin accumulation and the occurrence of fluff due to this, it does not suppress the occurrence of fluff, and the occurrence of fluff caused by the resin accumulated on the upper part of the resin reservoir control plate. Until then, there is room for improvement.

Japanese Patent No. 3049225 Japanese Patent No. 3064019 Japanese Patent Publication No.3-331823 Japanese Patent No. 4025820 JP 56-43435 A Special table 2007-518890 JP-A-52-151362 JP-A-1-282362 Japanese Patent Publication No. 4-12894 JP-A-9-111644 JP 2005-325191 A Japanese Patent Laid-Open No. 2001-300935 Japanese Patent Publication No. 2-26845

  An object of the present invention is to provide an apparatus and a method capable of producing a prepreg in which reinforcing fibers are not fuzzy and sufficiently opened.

  In one aspect of the present invention, a prepreg having a high quality and an arbitrary width is continuously impregnated into a reinforced fiber that has been spread with a thermoplastic resin that is in a high-viscosity molten state compared to a thermosetting resin. It is an object to provide an apparatus and a method that can be manufactured.

The apparatus for producing a prepreg of the present invention (Claim 1) uses a guide part for guiding a reinforcing fiber bundle, a comb part for aligning the reinforcing fiber bundle to be conveyed at equal intervals, and a fiber opening roller using a fiber opening roller. In a prepreg manufacturing apparatus having an opening part to be opened and a resin-impregnated part for impregnating a resin while moving the opened reinforcing fibers using a resin-impregnating roller, rotational speed rather smaller than the rotational speed of the resin impregnating rolls, the ratio of the rotational speed of the rotational speed of the open繊用roller and the resin impregnating rolls 55: 100 to 95: in the range of 100, the The diameter of the opening roller is smaller than the diameter of the resin-impregnated roller, and the resin-impregnated portion is configured to move the reinforcing fiber vertically downward .
In the present invention, the “rotation speed” indicates “speed (number of times) of rotation of the roller per unit time”.

  The apparatus for producing a prepreg according to claim 2 is characterized in that, in claim 1, the ratio of the rotation speed of the opening roller and the rotation speed of the resin impregnation roller is in the range of 70: 100 to 90: 100. It is what.

  The prepreg manufacturing apparatus according to claim 3 is characterized in that, in claim 1 or 2, the outer peripheral surface of the opening roller is an uneven surface.

  According to a fourth aspect of the present invention, there is provided the prepreg manufacturing apparatus according to the third aspect, wherein the unevenness treatment is a satin finish treatment.

According to a fifth aspect of the present invention, there is provided the prepreg manufacturing apparatus according to any one of the first to fourth aspects, wherein a plurality of opening rollers are provided .

Prepreg manufacturing apparatus 請 Motomeko 6, in any one of claims 1 to 5, in which reinforcing fibers characterized in that it is a carbon fiber.

A prepreg manufacturing apparatus according to a seventh aspect is the prepreg manufacturing apparatus according to any one of the first to sixth aspects, further comprising a creel stand portion for supplying the reinforcing fiber bundle to the guide portion. A bobbin formed by winding a reinforcing fiber bundle and a braking means for braking the rotation of the bobbin are provided.

The method for producing a prepreg according to the present invention (claim 8 ) uses a guide part for guiding a reinforcing fiber bundle, a comb part for aligning the reinforcing fiber bundles to be conveyed at equal intervals, and a fiber opening roller using a fiber opening roller. In a method for producing a prepreg by a prepreg production apparatus having an opening part to be opened and a resin-impregnated part that is impregnated with a resin while moving the opened reinforcing fibers using a resin impregnating roller, rotational speed of the open繊用roller rather smaller than the rotational speed of the resin impregnating rolls, the ratio of the rotational speed and the rotational speed of the resin impregnating rolls of the open繊用roller 55: 100 to 95: 100 The diameter of the opening roller is smaller than the diameter of the resin-impregnated roller, and the reinforcing fibers are moved vertically downward in the resin-impregnated portion .

The method for producing a prepreg according to claim 9 is characterized in that, in claim 8 , the ratio of the rotation speed of the opening roller and the rotation speed of the resin impregnation roller is in the range of 70: 100 to 90: 100. It is what.

The method for producing a prepreg according to claim 10 is characterized in that, in claim 8 or 9 , the outer peripheral surface of the opening roller is an uneven surface.

The method for producing a prepreg according to claim 11 is characterized in that, in claim 10 , the unevenness treatment is a satin finish treatment .

Method for producing a prepreg 請 Motomeko 12, in any one of claims 8 to 11, wherein the resin is characterized in that a thermoplastic resin.

A prepreg manufacturing method according to a thirteenth aspect is the method according to any one of the eighth to twelfth aspects, further comprising a creel stand portion for supplying a reinforcing fiber bundle to the guide portion. A bobbin formed by winding a reinforcing fiber bundle and a braking means for braking the rotation of the bobbin are provided.

A prepreg manufacturing method according to a fourteenth aspect is characterized in that, in the thirteenth aspect , the tension of the reinforcing fiber bundle unwound from the bobbin is controlled by controlling the braking force by the braking means.

A prepreg manufacturing method according to a fifteenth aspect is characterized in that, in any one of the eighth to fourteenth aspects, the reinforcing fiber is a carbon fiber .

In the present invention, the reinforcing fiber bundle is imparted with appropriate tension to the reinforcing fiber bundle due to the difference in rotation speed between the resin impregnation roller and the opening roller, and appropriate friction is applied to the reinforcing fiber on the surface of the opening roller. By doing so, the reinforcing fiber bundle is opened while preventing scratches and fuzz.
In the present invention, it is necessary that “the rotation speed of the opening roller is smaller than the rotation speed of the resin-impregnated roller”. Therefore, in order to obtain such an effect, the diameter of the opening roller is small. It is preferably smaller than the diameter of the impregnation roller.

  By applying braking to the rotation of the bobbin formed by winding the reinforcing fiber bundle, the reinforcing fiber bundle can be given appropriate friction and opened.

  In the present invention, when the reinforced fiber bundle that has been opened is impregnated with the resin, the traveling direction is preferably set vertically downward.

  In a conventional prepreg manufacturing apparatus, the traveling direction of the reinforcing fiber bundle in the resin-impregnated portion where the resin is impregnated with the opened reinforcing fiber bundle is set to the horizontal direction. Problems such as poor accuracy occur.

  On the other hand, the dripping of the resin in the resin-impregnated portion is prevented by setting the traveling direction of the reinforcing fiber bundle in the resin-impregnated portion to be vertically downward. In addition, the thickness accuracy is improved because the resin is uniformly dispersed on both sides of the reinforcing fiber compared to when the traveling direction is the horizontal direction.

FIG. 1 is a side view schematically showing the entire apparatus from a creel stand of a prepreg manufacturing apparatus of the present invention to a fiber opening device and a resin impregnated portion. FIG. 2 is a plan view schematically showing a creel stand of the prepreg manufacturing apparatus of the present invention. FIG. 3 is a plan view schematically showing a fiber opening device of the prepreg manufacturing apparatus of the present invention.

  Hereinafter, an example of the present invention will be described in detail with reference to the drawings. However, the description does not limit the present invention as long as it does not exceed the gist of the present invention.

  The prepreg manufacturing apparatus of FIG. 1 includes a creel stand 1 having a function of adjusting the tension of a reinforcing fiber bundle, a fiber opening device 2 for opening a reinforcing fiber bundle X drawn from the creel stand 1, and a fiber-reinforced reinforcement. And a laminator (including a resin-impregnated portion) 3 for impregnating the fiber bundle with a matrix resin made of a thermoplastic resin. A plurality of bobbins 4 around which the reinforcing fiber bundle X is wound are attached to the creel stand 1.

  The creel stand 1 is provided with a plurality of rotatable shafts 5, and a bobbin 4 is attached to each shaft 5.

  As this creel stand 1, in order to manufacture a unidirectional reinforcing fiber prepreg, for example, one having a tension adjusting function is preferable. As a method for adjusting the tension, there is a method for adjusting the tension with a movable roller described in Japanese Patent Publication No. 47-771, and an effective peripheral speed of the winding drum according to the tension of the fiber described in Japanese Patent Laid-Open No. 7-53128. And a method of adjusting the tension by changing the tension, a method of adjusting the tension by a pneumatic brake described in Japanese Utility Model Laid-Open No. 50-23445, and the like.

  In this embodiment, each shaft 5 is provided with a pneumatic brake 5a for applying tension to the drawn reinforcing fiber bundle X by braking (braking) the rotation of the shaft 5. The pneumatic brake 5a includes a rotating shaft that is linked to a shaft, a brake pad that is in sliding contact with the shaft, and a pneumatic actuator, and is configured to press the brake pad against the shaft by the pneumatic actuator.

  The air pressure of the actuator of the pneumatic brake 5a is preferably 4 MPa or less, more preferably 3 MPa or less, further preferably 2 MPa or less, particularly preferably 0.5 MPa or more and less than 1.5 MPa, and most preferably 0.7 or more and less than 1.2 MPa. It is a range.

  The reinforcing fiber bundle X drawn out from the creel stand 1 passes through the guide pole 6 of the creel stand 1 and subsequently passes through the guide 7, and further passes through the guide roller 8, and between the reinforcing fiber bundles at the comb portion (comb portion) 9. Are arbitrarily adjusted, and are sent to the fiber-spreading apparatus 2 in an orderly manner in parallel with each other.

  In the fiber opening device 2, the reinforcing fiber bundle travels via a plurality of (three in this embodiment) rollers 10 (10a, 10b, 10c). Each of the rollers 10 has a horizontal roller axis. In FIG. 1, the leading and trailing rollers 10a and 10c are arranged at a relatively high level, and the intermediate roller 10b is arranged at a relatively low level between them. The reinforcing fiber bundle X is hung on the high first roller (the leftmost in FIG. 1) 10a, hung on the low second roller 10b, and then on the high third roller 10c. It has been. Therefore, in a side view, the reinforcing fiber bundle X travels in a V shape. However, a total of three rollers 10 may be disposed on the high-order side, a total of two rollers 10 may be disposed on the low-order side, and the reinforcing fiber bundle X may be run in a zigzag in a W shape in a side view. Further, a larger number of rollers may be arranged. In this embodiment, the reinforcing fibers are run so as to form a V-shaped angle. However, running the reinforcing fibers at such an angle is extremely important for opening by friction. is there. Therefore, in the embodiment shown in FIG. 1, the intermediate roller 10b is disposed at a relatively lower position than the leading and trailing rollers 10a and 10c so that the reinforcing fibers are V-shaped. The roller 10b may be arranged so as to be relatively higher than the first and last rollers 10a and 10c, and is not limited to the embodiment shown in FIG.

  As the material of the opening roller 10, a stainless material is suitable. The surface of the roller 10 is preferably a satin surface in order to improve the smoothness and promote the widening of the fiber bundle and to suppress the occurrence of fluff. In order to prevent wear and to withstand long-term use, it is particularly preferable to perform a satin treatment after the chrome plating is applied to the roll surface.

  The reinforcing fiber bundle X hung on the roller 10c on the most downstream side (the rightmost side in FIG. 1) is then routed vertically downward and introduced into the laminator 3 from the fiber opening device 2. In this laminator 3, a pair of resin impregnating rollers 12 are arranged so that the roller axis is horizontal and the reinforcing fibers opened between them are sandwiched therebetween.

  The wound body of the laminate film 11 is arranged with the axial direction as the horizontal direction, slightly spaced from the resin impregnating rollers 12 and 12. The laminate film 11 unwound from each wound body is supplied between the rollers 12 and 12, and the reinforcing fibers are sandwiched between the laminate films 11 and 11. Further, a matrix resin supplier (not shown) supplies the molten or uncured liquid or powdery matrix resin Y to the portion where the reinforcing fibers between the laminate films 11 and 11 are drawn into the rollers 12 and 12. In this way, the opened reinforcing fiber is impregnated with the matrix resin Y by the laminator 3, and at the same time, sandwiched between the two laminated films 11, and the reinforcing fiber and the matrix resin are combined by the pressure of the roller 12 (nip pressure). To do.

  In this prepreg manufacturing apparatus, the rotation speed of the opening roller 10 is made lower than the rotation speed of the resin impregnation roller 12. Thereby, friction arises between the outer peripheral surface of the roller 10 for fiber opening, and the reinforcing fiber bundle X, and a reinforcing fiber bundle is loosened and opened by this friction. In addition, as above-mentioned, fiber opening is efficiently performed by making the uneven | corrugated surface of the outer peripheral surface of the roller 10 for fiber opening into a satin finish surface especially.

The ratio V ₁₀ / V ₁₂ × 100 (%) of the rotational speed V ₁₀ of the roller 10 to the rotational speed V ₁₂ of the roller ₁₂ is less than 100%, preferably 55 to 95%, particularly preferably 70 to 90%. is there.

When the outer peripheral surface of the roller 10 is an uneven surface, it is preferable that R _max (conforms to JIS B0601-1982) of the uneven surface is 1 to 10 μm, particularly 3 to 7 μm.

  The composite reinforcing fiber-containing prepreg is taken up by the take-up roller 14 through the guide roller 13 together with the laminate films 11 and 11. In a normal case, the laminate film 11 is peeled off and then used for various applications as a reinforced fiber-containing prepreg.

  In addition, it is preferable that the advancing direction of the reinforcing fiber in the vicinity of the roller 12 of the laminator 3 is vertically downward. In particular, it is preferable that the reinforcing fiber proceeds vertically downward in the section from the roller 10 c to the guide roller 13. When the matrix resin Y is a molten thermoplastic resin, the reinforcing fibers pass through the resin impregnation roller 12 from the roller 10c on the most downstream side of the spreader 2 and are impregnated with the resin, and then reach the guide roller 13. It is preferable that the resin is previously cooled to a temperature lower than its softening point and solidified so that the matrix resin and the reinforcing fiber are integrated.

  The unidirectional reinforcing fiber prepreg produced in the present invention is obtained by impregnating matrix resin into the reinforcing fibers arranged and aligned in one direction.

  In the present invention, the reinforced fiber refers to a fiber used for fiber reinforced plastic (FRP). The fiber is not particularly limited as long as it has sufficient strength and length that can be used in the production of a unidirectional prepreg and can be applied to the method of the present invention. For example, carbon fiber, graphite fiber, ceramic Examples include inorganic fibers such as fibers, glass fibers, and alumina fibers, aramid fibers, polyamide fibers, polyimide fibers, polyolefin fibers, polyester fibers, acrylic fibers, vinylon fibers, and organic fibers such as organic natural fibers. Carbon fiber is particularly preferable. Examples of the carbon fiber include polyacrylonitrile (PAN) -based, pitch-based, cellulose-based, and hydrocarbon vapor phase growth systems, and the use of PAN-based or pitch-based is preferable. These fibers may be used as a single type, but may be used as a plurality of types.

  The resin used in the present invention may be either a thermosetting resin or a thermoplastic resin, but is preferably a thermoplastic resin from the viewpoint of performance, storage management, productivity, etc. when it is used as a prepreg. The thermoplastic resin that can be used is not particularly limited. Specifically, polypropylene, polysulfone, polyethersulfone, polyetherketone, polyetheretherketone, polyamide, polyester, polycarbonate, polyetherimide, polyarylene oxide, polyimide, polyamide, Polyamideimide, polyacetal, polyphenylene oxide, polyphenylene sulfide, polyarylate, polyacrylonitrile, polyaramid and the like can be mentioned. Polypropylene, aromatic polyester, aromatic polyamide and aromatic polycarbonate are preferably used. The thermoplastic resin may be used as a single type, or a plurality of types may be used. Moreover, you may contain a well-known additive as needed.

  Hereinafter, Examples and Comparative Examples in which the carbon fiber bundles are opened and resin impregnated by variously changing the rotation speed difference between the roller of the fiber opening part and the roller of the resin impregnated part will be described. It is not limited at all by the example.

  The carbon fiber spread width and prepreg width measurement method and prepreg finish evaluation described in the Examples and Comparative Examples were each performed by the following methods.

[Carbon fiber spread width]
The spread width of the carbon fiber bundle is a measurement value obtained by measuring the width of the carbon fiber bundle after passing through the spread portion using a ruler.

[Prepreg width]
The width of the prepreg is a measurement value obtained by measuring the width of the prepreg after impregnation with a ruler.

[Finish evaluation of prepreg]
The presence or absence of fluffing of the spread part and prepreg and the impregnation state of the resin (whether the fibers are uniformly aligned in one direction) were visually observed and evaluated according to the following criteria.
A: The surface of the prepreg is not fuzzed, and the resin is uniformly impregnated. A: A portion of the surface of the prepreg is fuzzed, but the resin is uniformly impregnated. Δ: The resin is not impregnated. Uniform and defective appearance such as wrinkles on the prepreg surface

Examples 1 and 2 and Comparative Examples 1 and 6
In the apparatus shown in FIG. 1 (however, only one carbon fiber bundle was used), a polypropylene resin manufactured by Sanyo Chemical Industries Ltd., trade name Umex 1010 (softening point 145 ° C.) was melted at 180 ° C. as a matrix resin. Was supplied to the upper side of the laminate film 11. A PITCH carbon fiber dialead manufactured by Mitsubishi Plastics Co., Ltd. was used as the carbon fiber bundle, and a release film / trade name MRF38 manufactured by Mitsubishi Plastics Co., Ltd. was used as the laminate film. The air pressure of the pneumatic brake 5a was set to 1.0 MPa, and the rotational peripheral speed Vs _{12 of} the resin 12 impregnated portion was set to 20 cm / min (rotational speed V ₁₂ = 0.64 times / min). The diameter of the opening roller 10 is 40 mm, and the axial length is 400 mm. The surface of the opening roller 10 is a chrome-plated pear surface. The unevenness of the surface of the opening roller is R _max = 3 to 7 μm, the diameter of the resin impregnation roller 12 is 100 mm, and the axial length is 400 mm.

Open the roller rotational speed _{V 10} of the defibrating unit _V 10 _{/ V 12} × 100% 70% (Example 1), 90% (Example 2), 50% (Comparative Example 6), 100% (Comparative Example 1 The carbon fiber bundle was opened and impregnated with resin, and the evaluation results of the obtained prepreg are shown in Table 1.

[Discussion]
In Examples 1 and 2, the carbon fiber bundle was opened so that the width of the carbon fiber bundle was approximately 2.3 times from 6 mm to 14 mm, and problems such as fuzz that were a problem at the time of opening were observed. Thus, a uniform prepreg was obtained.

Also in Comparative Example 6, it was confirmed that the width of the carbon fiber bundle was opened approximately 6 times from 6 mm to 14 mm as in Example 1. However, under these conditions, the friction applied to the carbon fiber bundle was large, and in some cases, a non-uniform portion due to fluffing at the time of carbon fiber opening was observed.

  In Comparative Example 1, it was confirmed that the width of the carbon fiber bundle was opened approximately 6 times from 6 mm to 11 mm. However, almost no friction was applied to the carbon fiber bundle under these conditions, and the carbon fiber bundle was not sufficiently opened.

Examples 4-7
The peripheral speed _{Vs 12} of the resin impregnating rolls _{12 20cm / min (V 12 =} 0.64 times / min) (Example _{4), 30cm / min (V} 12 = 0.96 times / min) (Example 5 ) 10 cm / min (V ₁₂ = 0.32 times / min) (Example 6) or 50 cm / min (V ₁₂ = 1.59 times / min) (Example 7), and the air pressure of the pneumatic brake is 1. A prepreg was produced in the same manner as in the above example except that 0 MPa and V ₁₀ / V ₁₂ were set to 70%. The evaluation results of the spread width of each prepreg are shown in Table 2.

Comparative Examples 2-5
In Examples 4 to 7, prepregs were produced in the same manner except that Vs ₁₀ was changed so that V ₁₀ / V ₁₂ was 100%. The evaluation results of the spread width of each prepreg are shown in Table 3.

[Discussion]
In Examples 4 and 5, it was confirmed that the prepreg width was 35 mm, the amount of resin impregnation was good, and there were no defects such as voids and fluffing.

  In Example 6, it can be seen that the prepreg width was 27 mm and the carbon fiber bundle was opened. However, the resin impregnation amount of the reinforcing fiber prepreg may not necessarily be sufficient depending on the use because the resin impregnation is largely hindered by the nip pressure under these conditions. In addition, productivity may be insufficient.

  In Example 7, the prepreg width is 23 mm and the spread width is slightly narrow. In such a case, especially when the viscosity of the thermoplastic resin is high, the resin may pass through the resin-impregnated portion before sufficiently impregnating the carbon fiber bundle.

Examples 8-12
In Example 1 (Vs ₁₂ = 20 cm / min, V ₁₀ / V ₁₂ = 70%), the same applies except that the air pressure of the pneumatic brake 5a is 0.5, 1.0, 1.5, 0, or 2 MPa. Reinforcing fiber prepregs were manufactured, and fuzzing and resin impregnation were observed, and the results are shown in Table 4.

[Discussion]
In Examples 8 and 9, the carbon fibers were not fuzzed at the time of opening, and the carbon fibers were regularly arranged with appropriate tension even at the time of resin impregnation, and the fibers were uniformly and sufficiently opened. The finish was also good.

  In Example 10, fluffing and the like were observed in part, but the fibers were uniformly and sufficiently opened, and the finish of the prepreg was good.

  In Example 11, since the air pressure of the pneumatic brake without applying tension was set to 0 MPa, the obtained prepreg had a portion where the resin was not uniformly impregnated.

  In Example 12, since the air pressure of the pneumatic brake was as high as 2.0 MPa, some of the carbon fiber bundles were fluffed at the opened portion, and the prepreg also had a portion where the resin was not sufficiently impregnated.

  As in Examples 8-12, using a creel stand having a tension adjustment function using a pneumatic brake and using pitch-based carbon fiber, the tension adjustment mainly affects fuzzing and resin impregnation, It affects the finish. Using a pneumatic brake makes it easy to adjust the tension.

Examples 13 and 14
A prepreg was produced in the same manner as in Example 1 except that the air pressure of the pneumatic brake was 1.0 MPa and the carbon fiber bundle was 1 (Example 13) or 6 (Example 14). The width of was measured.

  As a result, in Example 13 with one carbon fiber bundle, the width of the prepreg was 35 mm. In Example 14 with six carbon fiber bundles, the width was 190 mm. Compared with the width 35 × 6 = 210 mm width when six open carbon fibers with an opening width of 35 mm are aligned, the width is reduced by about 10%. This is because carbon is used to prevent the occurrence of voids. This is because part of the fiber bundles overlap each other, and the spread width of the carbon fiber bundle is not reduced. From the above results, it was confirmed that even when a plurality of carbon fiber bundles were formed, the fibers were uniformly and sufficiently opened.

  As is clear from the above examples and comparative examples, according to the method and apparatus for producing a prepreg of the present invention, the reinforcing fibers can be sufficiently opened by providing a difference in rotational speed between the opening portion roller and the resin impregnated portion roller. It is possible to obtain a reinforced fiber prepreg which is fine and is impregnated uniformly with a resin. In addition, by adjusting the tension of the reinforcing fiber bundles quantitatively, the carbon fiber bundles are moderately rubbed by using an unevenly-treated opening roller without applying an excessive load to the reinforcing fiber bundles. It can be loosened, and the carbon fiber bundle can be opened well without cutting or fluffing.

  In addition, in the roller of the resin impregnated part after opening the reinforcing fiber bundle, by making the traveling direction of the reinforcing fiber vertically downward, the resin impregnation is uniform and both sides are uniform, and the quality of the opening prepreg Can be obtained without problems such as fluffing.

  Furthermore, according to the manufacturing method and apparatus of the present invention, the same effect can be exhibited regardless of whether the number of reinforcing fiber bundles to be opened is one or plural. This is because the elements related to the opening of the carbon fiber bundle are the rotation speed ratio between the rollers, and preferably the surface of the roller surface and the tension of the carbon fiber bundle by the pneumatic brake. However, it is considered that a constant tension is always applied to each carbon fiber bundle, and a stable spread prepreg can be obtained.

  In the examples, the opened reinforcing fibers are sandwiched between two release films, and impregnated by supplying molten polypropylene resin (trade name Umex 1010) to be combined between the release films. However, the opening device of the present invention is not limited to this method, and a prepreg can be produced in the same manner by an introduction method using another thermoplastic resin such as a powder method or a solution impregnation method.

DESCRIPTION OF SYMBOLS 1 Creel stand 2 Opening device 3 Laminator 4 Reinforcement fiber bobbin 5 Shaft 5a Pneumatic brake 6 Guide pole 7 Guide 8 Guide roller 9 Comb (comb part)
DESCRIPTION OF SYMBOLS 10 Roller of opening part 11 Laminated film 12 Roller of resin impregnation part 13 Guide roller 14 Winding roller X Reinforcement fiber Y Matrix resin

Claims (15)

A guide portion for guiding the reinforcing fiber bundle;
A comb portion for aligning the reinforcing fiber bundles to be conveyed at equal intervals;
An opening part for opening the reinforcing fiber bundle using an opening roller;
In an apparatus for producing a prepreg having a resin-impregnated portion that is impregnated with a resin while moving the opened reinforcing fibers using a resin-impregnating roller,
Rotational speed of the open繊用roller rather smaller than the rotational speed of the resin impregnating rolls, the ratio of the rotational speed and the rotational speed of the resin impregnating rolls of the open繊用roller 55: 100 to 95: 100 The diameter of the opening roller is smaller than the diameter of the resin impregnated roller,
The apparatus for producing a prepreg, wherein the resin impregnated portion is configured to move the reinforcing fiber vertically downward .   2. The prepreg manufacturing apparatus according to claim 1, wherein a ratio of a rotation speed of the opening roller and a rotation speed of the resin impregnation roller is in a range of 70: 100 to 90: 100.   3. The prepreg manufacturing apparatus according to claim 1 or 2, wherein an outer peripheral surface of the opening roller is an uneven surface.   The prepreg manufacturing apparatus according to claim 3, wherein the uneven treatment is a satin finish treatment.   The prepreg manufacturing apparatus according to any one of claims 1 to 4, wherein a plurality of opening rollers are provided. In any one of claims 1 to 5, the manufacturing apparatus of the prepreg, wherein the reinforcing fibers are carbon fibers. In any one of Claims 1 thru | or 6 , the creel stand part for supplying a reinforcing fiber bundle to the said guide part is provided,
The creel stand unit is provided with a bobbin formed by winding a reinforcing fiber bundle, and a braking means for braking the rotation of the bobbin. A guide portion for guiding the reinforcing fiber bundle;
A comb portion for aligning the reinforcing fiber bundles to be conveyed at equal intervals;
An opening part for opening the reinforcing fiber bundle using an opening roller;
In a method for producing a prepreg by a prepreg production apparatus having a resin-impregnated part which is impregnated with a resin while moving the opened reinforcing fiber using a resin impregnation roller,
Rotational speed of the open繊用roller rather smaller than the rotational speed of the resin impregnating rolls, the ratio of the rotational speed and the rotational speed of the resin impregnating rolls of the open繊用roller 55: 100 to 95: 100 The diameter of the opening roller is smaller than the diameter of the resin impregnated roller,
A method for producing a prepreg , wherein the reinforcing fibers are moved vertically downward in the resin-impregnated portion . The method for producing a prepreg according to claim 8 , wherein the ratio of the rotation speed of the opening roller and the rotation speed of the resin impregnation roller is in the range of 70: 100 to 90: 100. The method for producing a prepreg according to claim 8 or 9, wherein an outer peripheral surface of the opening roller is an uneven surface. The method for producing a prepreg according to claim 10, wherein the uneven treatment is a satin finish treatment. The method for producing a prepreg according to any one of claims 8 to 11 , wherein the resin is a thermoplastic resin. In any one of Claims 8 thru | or 12 , the creel stand part for supplying a reinforcing fiber bundle to the said guide part is provided,
A manufacturing method of a prepreg characterized in that a bobbin formed by winding a reinforcing fiber bundle and a braking means for braking the rotation of the bobbin are provided in the creel stand part. 14. The method for manufacturing a prepreg according to claim 13 , wherein the tension of the reinforcing fiber bundle unwound from the bobbin is controlled by controlling the braking force by the braking means. The method for producing a prepreg according to any one of claims 8 to 14 , wherein the reinforcing fiber is a carbon fiber.

Images