Method for manufacturing carbon fiber sheet molding compound and apparatus for manufacturing carbon fiber sheet molding compound

Abstract

One of the main purposes of the present invention is to provide improvements pertaining to a method for producing a carbon fiber sheet molding compound.　This method for producing a carbon fiber sheet molding compound includes transferring a continuous carbon fiber bundle pulled out from a package to a chopper via a guide tube, performing loosening treatment of the continuous carbon fiber bundle prior to the passage thereof through the guide tube, cutting the continuous carbon fiber bundle by means of the chopper, dropping the chopped carbon fiber bundle thus generated onto a moving carrier film and thereby forming a random mat, and impregnating the random mat with a paste comprising a thermosetting resin composition.

Description

Technical Field

[0001] The present invention mainly relates to a method for manufacturing a carbon fiber sheet molding compound and an apparatus for manufacturing a carbon fiber sheet molding compound. This application claims priority based on Japanese Patent Application No. 2023-2937 filed with the Japan Patent Office on January 12, 2023, and incorporates the content herein by reference.

Background Art

[0002] Carbon fiber reinforced plastic (CFRP) is a composite material using carbon fiber as a reinforcing material. Since CFRP is high-strength and lightweight, in recent years, it has been used for parts of various transportation equipment including automobiles, ships, railway vehicles, manned aircraft, and unmanned aircraft. One of the intermediate materials used for molding CFRP products is carbon fiber sheet molding compound (hereinafter also referred to as "CF-SMC"). CF-SMC is manufactured by forming a random mat with chopped carbon fiber bundles obtained by cutting continuous carbon fiber bundles short, and impregnating the random mat with a paste of a thermosetting resin composition.

[0003] When manufacturing a composite material reinforced with chopped carbon fiber bundles, a technique has been proposed in which the continuous carbon fiber bundle before cutting with a chopper is processed with a roll with protrusions. When the continuous carbon fiber bundle is cut after being loosened by this process, many chopped carbon fiber bundles with a high reinforcing effect and having a bundle size smaller than the bundle size of the continuous carbon fiber bundle before cutting are produced (Patent Document 1). The bundle size of the carbon fiber bundle means the number of carbon fiber filaments constituting the carbon fiber bundle (the same shall apply hereinafter).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

[0005] One of the objectives of the present invention is to provide an improvement to a method for manufacturing carbon fiber sheet molding compounds. Another object of the present invention is to provide an improvement to the apparatus for manufacturing carbon fiber sheet molding compounds. Problems addressed by each embodiment of the present invention may be disclosed explicitly or implicitly herein. [Means for solving the problem]

[0006] According to one aspect of the present invention, a method for producing a carbon fiber sheet molding compound is provided, comprising: sending a continuous carbon fiber bundle drawn from a package through a guide tube to a chopper; loosening the continuous carbon fiber bundle before passing it through the guide tube; cutting the continuous carbon fiber bundle in the chopper and dropping the resulting chopped carbon fiber bundle onto a running carrier film to form a random mat; and impregnating the random mat with a paste made of a thermosetting resin composition.

[0007] According to another aspect of the present invention, a method for manufacturing a carbon fiber sheet molding compound is provided, comprising: sending a continuous carbon fiber bundle drawn from a package to a chopper; loosening the continuous carbon fiber bundle before cutting it in the chopper; dropping the chopped carbon fiber bundle resulting from cutting the continuous carbon fiber bundle in the chopper onto a moving carrier film to form a random mat; and impregnating the random mat with a paste made of a thermosetting resin composition, wherein the distance traveled by the continuous carbon fiber bundle from the loosening treatment to cutting in the chopper is more than 3 m.

[0008] A method for producing a carbon fiber sheet molding compound is provided, comprising: dropping chopped carbon fiber bundles, which are produced by cutting a continuous carbon fiber bundle with a chopper, onto a moving carrier film to form a random mat; impregnating the random mat with a paste made of a thermosetting resin composition; loosening the continuous carbon fiber bundle before cutting with the chopper; and dispersing the chopped carbon fiber bundles with a rotationally driven dispersion roll before dropping them onto the carrier film.

[0009] A method for manufacturing a carbon fiber sheet molding compound is provided, comprising: dropping chopped carbon fiber bundles, which are produced by cutting a continuous carbon fiber bundle with a chopper, onto a running carrier film to form a random mat; impregnating the random mat with a paste made of a thermosetting resin composition; and dividing the space into a plurality of regions along the T direction from which the chopped carbon fiber bundles fall toward the carrier film by at least one partition, wherein the at least one partition is made of metal and grounded.

[0010] According to yet another aspect of the present invention, a manufacturing apparatus for a carbon fiber sheet molding compound is provided, comprising: a chopper positioned above a travel path for a carrier film; a guide tube for passing a continuous carbon fiber bundle through which a continuous carbon fiber bundle is drawn from a package and sent to the chopper; and a bundle loosener positioned upstream of the guide tube for loosening the continuous carbon fiber bundle.

[0011] According to yet another aspect of the present invention, a carbon fiber sheet molding compound manufacturing apparatus is provided, comprising a chopper positioned above a travel path of a carrier film, and a bundle loosener for loosening continuous carbon fiber bundles drawn from a package and sent to the chopper, wherein the distance from the bundle loosener to the chopper along the travel path of the continuous carbon fiber bundles is greater than 3 m.

[0012] According to yet another aspect of the present invention, a carbon fiber sheet molding compound manufacturing apparatus is provided, comprising: a chopper positioned above a travel path of a carrier film; a bundle loosening device for loosening continuous carbon fiber bundles sent to the chopper; and a rotationally driven dispersion roll for dispersing chopped carbon fiber bundles resulting from cutting the continuous carbon fiber bundles in the chopper.

[0013] According to yet another aspect of the present invention, a carbon fiber sheet molding compound manufacturing apparatus is provided, comprising a chopper positioned above a travel path of a carrier film, and at least one partition made of metal and grounded, wherein the at least one partition divides the space into a plurality of regions along the T direction into which chopped carbon fiber bundles, resulting from the cutting of continuous carbon fiber bundles by the chopper, fall toward the travel path. [Effects of the Invention]

[0014] According to a preferred embodiment, improvements are provided to a method or apparatus for manufacturing carbon fiber sheet molding compounds. [Brief explanation of the drawing]

[0015] [Figure 1] Figure 1 shows the configuration of a CF-SMC manufacturing apparatus according to one embodiment. [Figure 2] Figure 2 shows an example of a roll with protrusions. [Figure 3] Figure 3 shows a gear pair consisting of two spur gears that mesh with each other, with a continuous carbon fiber bundle attached to them. [Figure 4] Figure 4 shows the spacing between two gears forming a gear pair widened to allow the splice between continuous carbon fiber bundles to pass through. [Figure 5] Figure 5 shows a bundle loosening device in which only one continuous carbon fiber bundle is processed at a time by a single gear pair. [Figure 6] Figure 6 shows the configuration of the chopper. [Figure 7] FIG. 7 shows an example of a pin roll. [Figure 8] FIG. 8 shows an example of a cage roll and shows the cage roll as viewed from a direction parallel to the rotation axis. [Figure 9] FIG. 9 shows the cage roll of FIG. 8 as viewed from a direction perpendicular to the rotation axis. [Figure 10] FIG. 10 shows a place where a booth is provided and the main part of a pin roll type dispersion roll is arranged therein. The traveling direction of the first carrier film is a direction from left to right within the paper surface. [Figure 11] FIG. 11 shows a place where a booth is provided and the main part of a pin roll type dispersion roll is arranged therein. The traveling direction of the first carrier film is a direction from the back to the front of the paper surface. [Figure 12] FIG. 12 shows a space where chopped carbon fiber bundles generated by cutting a continuous carbon fiber bundle with a chopper fall is partitioned into a plurality of regions along the T direction by a partition arranged below the chopper. The traveling direction of the first carrier film is a direction from the back to the front of the paper surface.

Embodiments for Carrying Out the Invention

[0016] Hereinafter, some embodiments of the present invention will be described with reference to the drawings as appropriate. The dimensional ratios in the drawings are for convenience of explanation and may be different from the actual ones. Also, the same components in the drawings are denoted by the same reference numerals, and the description of overlapping components may be omitted.

[0017] 1. Method and Apparatus for Manufacturing CF-SMC The production of CF-SMC by the production method according to an embodiment of the present invention can be carried out, for example, using a production apparatus having a basic configuration shown in FIG. 1. The CF-SMC production apparatus 70 shown in FIG. 1 includes a bundle loosener BL, a guide tube GT, a guide roll GR, a chopper 1, a first coater 2a, a second coater 2b, and an impregnator 3. Chopper 1 is positioned above the travel path of the first carrier film 51. When the first carrier film 51 travels below chopper 1, its surface is held horizontally. In this specification, the direction perpendicular to the running direction of the first carrier film and horizontal to it may be referred to as the T direction. In Figure 1, the T direction is perpendicular to the plane of the paper.

[0018] A preferred embodiment of the method for manufacturing CF-SMC, using the manufacturing apparatus shown in Figure 1 as an example, is described below. First, the continuous carbon fiber bundle 10 is drawn out from the package P. The package P may or may not use a bobbin. The bundle size of the continuous carbon fiber bundle 10 is usually 12K or larger, but may also be 15K or larger, 18K or larger, 24K or larger, 36K or larger, 40K or larger, 48K or larger, etc. There is no particular upper limit to the bundle size of the continuous carbon fiber bundle 10, but it may be 200K or smaller, 150K or smaller, 100K or smaller, 80K or smaller, 60K or smaller, etc. Here, K is a symbol representing 1000, for example, 12K means 12000, 48K means 48000, and 100K means 100000.

[0019] The continuous carbon fiber bundle 10, drawn from package P, is loosened by a bundle loosening device BL before being passed through guide tube GT. Loosening a carbon fiber bundle means weakening the bonds between the carbon fiber filaments that make up the bundle. In a carbon fiber bundle, the carbon fiber filaments are bonded to each other through a resin called a sizing agent, so the carbon fiber bundle can be loosened by applying mechanical force from the outside to partially break these bonds.

[0020] Chopped carbon fiber bundles obtained by cutting loosened continuous carbon fiber bundles contain more bundles with smaller sizes compared to chopped carbon fiber bundles obtained by cutting the same continuous carbon fiber bundles without loosening them. This is because loosened continuous carbon fiber bundles tend to separate into multiple bundles when cut. As described in the aforementioned Patent Document 1, it is well known among those skilled in the art that finely chopped carbon fiber bundles with smaller bundle sizes provide a higher reinforcing effect when used in CFRP.

[0021] One example of a bundle loosening device may include means for piercing a continuous carbon fiber bundle with protrusions. A typical example of such means is a protruding roll. As shown in Figure 2, the protruding roll 11 is a roll with a number of protrusions 12 arranged on its outer circumference. A preferred example of a protruding roll includes the one described in the aforementioned Patent Document 1. The peripheral speed on the outer circumference of the protruding roll is set to be approximately equal to the feed rate of the continuous carbon fiber bundle, for example, within a range of 0.9 to 1.1 times the feed rate. The angle at which the continuous carbon fiber bundle is gripped on the protruding roll is preferably 30° or more, more preferably 60° or more, and even more preferably 90° or more. Sufficient tension is applied to the continuous carbon fiber bundle so that the protrusions penetrate it reliably.

[0022] The arrangement pattern of the multiple protrusions on the surface of the protruding roll preferably has periodicity in the circumferential and axial directions. The circumferential period is preferably 10 mm or less, more preferably 5 mm or less. The axial period is preferably 5 mm or less, more preferably 3 mm or less. There is no particular lower limit to each period, but it may be, for example, 1 mm or more.

[0023] Multiple continuous carbon fiber bundles can be arranged parallel to each other and fed onto a single protruding roll, allowing for simultaneous loosening. The bundle loosening device may further include means for spreading the continuous carbon fiber bundle upstream or downstream of the means for piercing the continuous carbon fiber bundle with projections. Examples of means for spreading the carbon fiber bundle include spreader rolls and spreader bars.

[0024] An example of a bundle loosening device may have a gear pair consisting of two gears that mesh with each other. The two gears are preferably spur gears. As shown in Figure 3, when a continuous carbon fiber bundle 10 is meshed with a gear pair 14 consisting of two gears 13, 13, it bends with a small radius, so the bonds between filaments mediated by the sizing agent are partially broken and the continuous carbon fiber bundle loosens. The gear pair only needs to rotate passively and does not need to be connected to a power source to rotate actively. This method using a gear pair allows for bending a continuous carbon fiber bundle at a small radius without applying any tension. In other words, it allows for easy loosening of a continuous carbon fiber bundle without the need to introduce a tension application mechanism.

[0025] The material of the two gears constituting a gear pair can be polymer or metal. The tooth height of each gear (the difference between the root radius and the apex radius) may be, for example, 1 to 10 mm, or 2 to 5 mm. The length obtained by dividing the circumference of the apex circle by the number of teeth (the spacing between teeth along the circumference of the apex circle (pitch)) may be, for example, 1 to 10 mm, or 3 to 7 mm. In one example, each gear can have a tooth height of approximately 3.5 mm and a length obtained by dividing the circumference of the apex circle by the number of teeth of approximately 5 mm.

[0026] By splicing the end of a continuous carbon fiber bundle drawn from one package with the beginning of a continuous carbon fiber bundle drawn from the next package to be used, CF-SMC can be continuously manufactured without stopping the line each time a package becomes empty. However, the splice portion between the continuous carbon fiber bundles is thicker than other parts and cannot be engaged with the gear pair. Therefore, in a preferred example, as shown in Figure 4, the distance between the two gears 13, 13 forming the gear pair 14 may be widened only when the splice portion 15 passes through.

[0027] As shown in Figure 5, it is preferable that only one continuous carbon fiber bundle 10 is processed at a time by a single gear pair 14. Therefore, in order to loosen N continuous carbon fiber bundles simultaneously, it is preferable to install at least N gear pairs in the bundle loosening device. In this case, when only the splice portion of one of the N continuous carbon fiber bundles passes through the bundle loosening device at a given time, it is only necessary to widen the distance between the two gears that make up the gear pair processing that continuous carbon fiber bundle.

[0028] One example of a bundle loosening device may loosen a continuous carbon fiber bundle by applying sufficient tension to it and then passing it through a curved path formed using rollers and / or bars. Such a bundle loosening device may also have the effect of spreading the carbon fiber bundle apart.

[0029] Because the space between the downstream end of the guide tube GT and the chopper 1 is limited, installing the bundle loosening device BL there would not only be inconvenient when adjusting, maintaining, and repairing the bundle loosening device, but also make it difficult to adjust, maintain, and repair the chopper. In contrast, there is often ample space upstream of the guide tube GT, so placing the bundle loosening device there makes adjustment, maintenance, inspection, and repair of the bundle loosening device BL much easier. This is extremely important when using a bundle loosening device that engages continuous carbon fiber bundles with gear pairs, and when installing the same number of gear pairs as the number of continuous carbon fiber bundles being processed. Since the process of loosening continuous carbon fiber bundles is unlikely to cause fiber filament breakage, the problem of short carbon fiber filaments agglomerating and becoming cotton-like debris within the guide tube is not exacerbated by installing the bundle loosening device upstream of the guide tube.

[0030] The continuous carbon fiber bundle 10, loosened by the bundle loosening device BL, is sent to the chopper 1 through the guide tube GT. There are no limitations on the material of the guide tube; it may be polymer or metal. The length of the guide tube GT can be appropriately determined depending on the distance from the installation location of the bundle loosening device BL to the chopper 1. In one example, the length of the guide tube may be 3m or more, 5m or more, or 7m or more. This means that the distance traveled by the continuous carbon fiber bundle 10 from when it is loosened by the bundle loosening device BL until it is cut by the chopper 1, in other words, the distance from the bundle loosening device BL to the chopper 1 along the path of the continuous carbon fiber bundle 10, may be more than 3m, more than 5m, or even more than 7m. There is no specific upper limit to the length of the guide tube, but in most cases, 15m or less, or even 10m or less, is sufficient. If the guide tube is longer than necessary, it becomes difficult to clean the inside.

[0031] As shown in Figure 6 as an example, the chopper 1 consists of a receiving roll 22 that also serves as a feed roll, a pinch roll 23, and a cutter roll 24. The outer circumference of the receiving roll 22 is made of rubber. The continuous carbon fiber bundle 10 is cut by being pressed against the receiving roll 22 by a blade 25 attached to the outer circumference of the cutter roll 24. The fiber length of the carbon fibers contained in the chopped carbon fiber bundle 20 is, for example, in the range of 5 to 100 mm, preferably in the range of 5 to 60 mm, and more preferably in the range of 10 to 30 mm.

[0032] The chopped carbon fiber bundles 20, which are created when the continuous carbon fiber bundles 10 are cut by the chopper 1, fall toward the moving first carrier film 51. The fallen chopped carbon fiber bundles 20 form a random mat 30 on the first carrier film 51. Upstream of the point where the chopped carbon fiber bundle 20 falls, a paste 41 of a thermosetting resin composition is applied to the upper surface of the first carrier film 51 by a first coating machine 2a. The viscosity of the paste is preferably adjusted to be in the range of 1 to 30 Pa·s at 25°C. A paste 42 having the same composition as paste 41 is applied to the second carrier film 52 by a second coating machine 2b. The first carrier film 51 and the second carrier film 52 are stacked with the random mat 30 in between, so that the surfaces coated with paste 41 and 42 face each other, thereby forming a laminate 60.

[0033] The laminate 60 is compressed in the impregnation machine 3 and then wound onto a bobbin. In another example, the laminate 60 may be folded and stored in a container. When the laminate 60 is compressed in the impregnation machine 3, the random mat 30 is impregnated with pastes 41 and 42. After impregnation, the paste thickens, completing the CF-SMC. Thickening agents are usually added to pastes 41 and 42 so that the CF-SMC has appropriate tack and firmness. The amount of thickening agent added is adjusted so that pastes 41 and 42 do not thicken too much before impregnation.

[0034] Examples of materials for the first and second carrier films include polyolefins such as polyethylene and polypropylene, polyvinylidene chloride, vinyl chloride, and polyamide. The first and second carrier films may each be multilayer films. The first carrier film and the second carrier film may have a thickness in the range of, for example, 10 μm to 500 μm. The first carrier film and the second carrier film may have a width in the range of, for example, 0.5 m to 1.5 m.

[0035] In one example, a paste made from a thermosetting resin composition may contain a liquid epoxy resin, an epoxy curing agent, a thickener, and optional components. Examples of optional components include low-shrinkage agents, internal release agents, colorants, flame retardants, and antioxidants, as well as modifiers made from rubber, elastomers, or thermoplastic resins. In another example, a paste made of a thermosetting resin composition contains at least one of a vinyl ester resin and an unsaturated polyester resin, together with a reactive diluent, a polymerization initiator, a thickener, and optional components. The reactive diluent is a liquid vinyl compound, examples of which include styrene and various (meth)acrylates. Examples of optional components include polymerization inhibitors, low-shrinkage agents, internal release agents, colorants, flame retardants, and antioxidants, as well as modifiers made of rubber, elastomers, or thermoplastic resins.

[0036] The CF-SMC manufacturing method described above can be further modified as described below. In one modified example, the chopped carbon fiber bundle may be dispersed using a rotationally driven dispersion roll before being dropped onto the first carrier film. The axis of rotation of the dispersion roll is preferably parallel to the T direction. An example of a dispersion roll is a pin roll (also called a spike roll). As shown in Figure 7, the main part 32 of the pin roll 31 has a structure in which multiple pins 34 protrude from the surface of a cylinder 33. The direction of all of the multiple pins 34 is perpendicular to the axis of rotation. The shaft 35 passes through the center of the cylinder 33. When the pin roll 31 is rotated, the pins 34 of the main part 32 strike the chopped carbon fiber bundle.

[0037] Another example of a distributed roll is a cage roll. As shown in an example in Figures 8 and 9, the main part 37 of a cage roll 36 has a structure in which several rods 39 are stretched between a pair of discs 38, 38 that share a rotation axis. The rods 39 can be replaced with rods with a non-round cross-section, such as square or flat bars, or with taut wires. A shaft 40 passes through the center of each disc. When the cage roll rotates, the main rod strikes the chopped carbon fiber bundles.

[0038] A common feature of both pin rolls and cage rolls is that the shape of the main part has n-fold rotational symmetry around the axis of rotation (the central axis of the shaft), where n is a finite integer of 1 or more. Preferably, n is between 3 and 72, but may be 45 or less, 36 or less, or 24 or less. For example, in the pin roll 31 shown in Figure 7, n is 4, and in the cage roll 36 shown in Figures 8 and 9, n is 6. If this feature is present, even rolls other than pin rolls or cage rolls can be used to physically strike the chopped carbon fiber bundles when rotated.

[0039] When chopped carbon fiber bundles are dispersed using a rotating dispersion roll, the physical impact breaks down the chopped carbon fiber bundles into smaller carbon fiber bundles. This effect is more pronounced if the continuous carbon fiber bundles are loosened before being cut with the chopper. On the other hand, physically striking a chopped carbon fiber bundle, in which the bonds between fiber filaments are weakened, easily generates fine carbon fiber dust that can float in the air. To prevent this carbon fiber dust from spreading, it is preferable to provide a booth 43, as shown in Figures 10 and 11, and to place the main part of the dispersion roll 44 inside it, as well as to provide an opening in the ceiling of the booth and guide the chopped carbon fiber bundle to this opening using a chute 45. The arrow X in Figure 10 indicates the direction of travel of the first carrier film 51. The double arrow T in Figure 11 indicates the T direction.

[0040] The width of the booth in the T-direction is preferably narrower than the width of the first carrier film 51, as shown in the example in Figure 11, but it is not limited to this. It is desirable that the ends of the shafts of the dispersion rolls protrude to the outside of the booth through an opening provided in the side wall of the booth (a wall parallel to the direction of travel of the first carrier film). In the example in Figure 11, the bearings 46 that support the dispersion rolls 44 are located outside the booth 43, and substantially only the main part of the dispersion rolls 44 is located inside the booth 43.

[0041] Furthermore, to prevent carbon fiber dust from escaping outside the booth, it is desirable to continuously remove carbon fiber dust from inside the booth using a dust collector while CF-SMC is being manufactured. In the example in Figure 10, carbon fiber dust can be removed from inside the booth 43 using a dust collector 49 connected to the booth 43 via a hose 47. A preferred example of a dust collector, though not limited to the dust collector, is a dust collector equipped with a separator that uses centrifugal force to separate dust from air, i.e., a cyclone dust collector. The suction port connected to the dust collector is preferably provided on either the wall of the booth or inside the booth, or both. If necessary, carbon fiber dust that leaks outside the booth may be removed using a dust collector.

[0042] The following are reasons why the spread of carbon fiber dust should be prevented: Carbon fiber dust can float on air currents and then settle in specific locations, forming cotton-like debris. If this cotton-like debris gets mixed into the random mat, it can cause impregnation problems. Carbon fiber dust can contaminate the mechanical components of SMC manufacturing equipment, potentially disrupting its operation. • Carbon fiber dust worsens the working environment in rooms where SMC manufacturing equipment is installed. Because carbon fiber dust is conductive, it can interfere with the operation of electrical and electronic equipment attached to SMC manufacturing equipment and electrical and electronic equipment used in the room where SMC manufacturing equipment is installed.

[0043] In another modification, as shown in Figure 12, at least one partition 48 positioned below the chopper 1 can divide the space through which the chopped carbon fiber bundles fall, resulting from the cutting of a continuous carbon fiber bundle by the chopper 1, into multiple regions along the T-direction. Preventing the chopped carbon fiber bundles from moving along the T-direction as they fall through this space with the partition is useful in uniformizing the basis weight of the random mat formed on the first carrier film along the T-direction. When the aforementioned dispersion rolls are placed below the chopper, placing a partition below the dispersion rolls can mitigate the adverse effect of the airflow generated by the rotation of the dispersion rolls on the uniformity of the random mat's weight.

[0044] When fibrous dust adheres to a partition due to static electricity, the attached fibrous dust can aggregate and form cotton-like debris. To prevent this, it is desirable to form the partition from metal and to ground it. Preferred examples of metals include aluminum alloys and stainless steel, with aluminum alloys being more preferred due to their high conductivity. When partitions become scratched, fibrous dust can easily get caught in the scratches, which in turn can lead to the formation of cotton-like debris. Since aluminum alloy plates are easily scratched, electroless nickel plating may be applied to increase surface hardness and make them more resistant to scratches.

[0045] 2. Summary of Embodiments In summary, embodiments of the present invention include, but are not limited to, the following. [Embodiment 1] A method for producing a carbon fiber sheet molding compound, comprising: feeding a continuous carbon fiber bundle drawn from a package through a guide tube to a chopper; loosening the continuous carbon fiber bundle before passing it through the guide tube; cutting the continuous carbon fiber bundle in the chopper and dropping the resulting chopped carbon fiber bundle onto a running carrier film to form a random mat; and impregnating the random mat with a paste made of a thermosetting resin composition. [Embodiment 2] The manufacturing method according to Embodiment 1, wherein the loosening process includes piercing the continuous carbon fiber bundle with protrusions. [Embodiment 3] A manufacturing method according to Embodiment 2, wherein a roll with protrusions is used for the loosening process. [Embodiment 4] A manufacturing method according to any one of Embodiments 1 to 3, wherein the loosening process includes bending the continuous carbon fiber bundle. [Embodiment 5] The manufacturing method according to Embodiment 4, wherein the loosening process uses a gear pair consisting of two gears that mesh with each other and may each be a spur gear. [Embodiment 6] A manufacturing method according to any one of Embodiments 1 to 5, wherein the chopped carbon fiber bundle is dispersed by a rotationally driven dispersion roll and then dropped onto the carrier film. [Embodiment 7] A manufacturing method according to Embodiment 6, further comprising providing a booth and arranging the main part of the dispersion roll inside it, and using a chute to guide the chopped carbon fiber bundle into an opening provided in the ceiling of the booth. [Embodiment 8] A manufacturing method according to Embodiment 6 or 7, further comprising dispersing the chopped carbon fiber bundle with the dispersion roll and removing the resulting fiber dust with a dust collector. [Embodiment 9] A manufacturing method according to Embodiment 7, further comprising dispersing the chopped carbon fiber bundle with the dispersion roll and removing the resulting fiber dust with a dust collector, wherein a suction port connected to the dust collector is provided on either the wall of the booth or inside the booth, or both. [Embodiment 10] A manufacturing method according to any one of Embodiments 1 to 9, further comprising dividing the space in which the chopped carbon fiber bundle falls toward the carrier film into a plurality of regions along the T direction by at least one partition. [Embodiment 11] A manufacturing method according to Embodiment 10, wherein at least one partition is made of metal and is grounded. [Embodiment 12] A manufacturing method according to any of Embodiments 1 to 11, wherein the length of the guide tube is 3 m or more, and may be 5 m or more or 7 m or more.

[0046] [Embodiment 13] A method for manufacturing a carbon fiber sheet molding compound, comprising: sending a continuous carbon fiber bundle drawn from a package to a chopper; applying a loosening treatment to the continuous carbon fiber bundle before cutting it in the chopper; dropping the chopped carbon fiber bundle resulting from cutting the continuous carbon fiber bundle in the chopper onto a running carrier film to form a random mat; and impregnating the random mat with a paste made of a thermosetting resin composition, wherein the distance traveled by the continuous carbon fiber bundle from the loosening treatment to cutting in the chopper is more than 3m, more than 5m, or more than 7m. [Embodiment 14] A manufacturing method according to Embodiment 13, wherein the loosening process includes piercing the continuous carbon fiber bundle with protrusions. [Embodiment 15] A manufacturing method according to Embodiment 14, wherein a roll with protrusions is used for the loosening process. [Embodiment 16] A manufacturing method according to any one of Embodiments 13 to 15, wherein the loosening process includes bending the continuous carbon fiber bundle. [Embodiment 17] The manufacturing method according to Embodiment 16, wherein the loosening process uses a gear pair consisting of two gears that mesh with each other and may each be a spur gear. [Embodiment 18] A manufacturing method according to any one of embodiments 13 to 17, wherein the chopped carbon fiber bundle is dispersed by a rotationally driven dispersion roll and then dropped onto the carrier film. [Embodiment 19] A manufacturing method according to Embodiment 18, further comprising providing a booth and arranging the main part of the dispersion roll inside it, and using a chute to guide the chopped carbon fiber bundle into an opening provided in the ceiling of the booth. [Embodiment 20] A manufacturing method according to Embodiment 18 or 19, further comprising dispersing the chopped carbon fiber bundle with the dispersion roll and removing the resulting fiber dust with a dust collector. [Embodiment 21] A manufacturing method according to Embodiment 19, further comprising dispersing the chopped carbon fiber bundle with the dispersion roll and removing the resulting fiber dust with a dust collector, wherein a suction port connected to the dust collector is provided on either the wall of the booth or inside the booth, or both. [Embodiment 22] A manufacturing method according to any one of embodiments 13 to 21, further comprising dividing the space in which the chopped carbon fiber bundle falls toward the carrier film into a plurality of regions along the T direction by at least one partition. [Embodiment 23] The manufacturing method according to Embodiment 22, wherein at least one partition is made of metal and is grounded. [Embodiment 24] A manufacturing method according to any one of Embodiments 13 to 23, wherein the continuous carbon fiber bundle is sent to the chopper through a guide tube, and the continuous carbon fiber bundle is subjected to the loosening treatment before being passed through the guide tube.

[0047] [Embodiment 25] A method for manufacturing a carbon fiber sheet molding compound, comprising: dropping chopped carbon fiber bundles, which are produced by cutting continuous carbon fiber bundles with a chopper, onto a moving carrier film to form a random mat; impregnating the random mat with a paste made of a thermosetting resin composition; loosening the continuous carbon fiber bundles before cutting them with the chopper; and dispersing the chopped carbon fiber bundles with a rotationally driven dispersion roll before dropping them onto the carrier film. [Embodiment 26] A manufacturing method according to Embodiment 25, further comprising providing a booth and arranging the main part of the dispersion roll inside it, and using a chute to guide the chopped carbon fiber bundle into an opening provided in the ceiling of the booth. [Embodiment 27] A manufacturing method according to Embodiment 25 or 26, further comprising dispersing the chopped carbon fiber bundle with the dispersion roll while removing the resulting fiber dust with a dust collector. [Embodiment 28] A manufacturing method according to Embodiment 26, further comprising dispersing the chopped carbon fiber bundle with the dispersion roll and removing the resulting fiber dust with a dust collector, wherein a suction port connected to the dust collector is provided on either the wall of the booth or inside the booth, or both. [Embodiment 29] A manufacturing method according to any one of Embodiments 25 to 28, wherein the loosening process includes piercing the continuous carbon fiber bundle with protrusions. [Embodiment 30] A manufacturing method according to Embodiment 29, wherein a roll with protrusions is used for the loosening process. [Embodiment 31] A manufacturing method according to any one of Embodiments 25 to 30, wherein the loosening process includes bending the continuous carbon fiber bundle. [Embodiment 32] The manufacturing method according to Embodiment 31, wherein the loosening process uses a gear pair consisting of two gears that mesh with each other and may each be a spur gear. [Embodiment 33] A manufacturing method according to any one of embodiments 25 to 32, further comprising dividing the space in which the chopped carbon fiber bundle falls toward the carrier film into a plurality of regions along the T direction by at least one partition. [Embodiment 34] The manufacturing method according to Embodiment 33, wherein at least one partition is made of metal and is grounded.

[0048] [Embodiment 35] A method for manufacturing a carbon fiber sheet molding compound, comprising: dropping chopped carbon fiber bundles, which are produced by cutting a continuous carbon fiber bundle with a chopper, onto a running carrier film to form a random mat; impregnating the random mat with a paste made of a thermosetting resin composition; and dividing the space into a plurality of regions along the T direction from which the chopped carbon fiber bundles fall toward the carrier film by at least one partition, wherein the at least one partition is made of metal and grounded. [Embodiment 36] A manufacturing method according to Embodiment 35, wherein the chopped carbon fiber bundle is dispersed by a rotationally driven dispersion roll and then dropped onto the carrier film. [Embodiment 37] A manufacturing method according to Embodiment 36, further comprising providing a booth in which the main part of the dispersion roll and the at least one partition are placed, and using a chute to guide the chopped carbon fiber bundle into an opening provided in the ceiling of the booth. [Embodiment 38] A manufacturing method according to Embodiment 36 or 37, further comprising dispersing the chopped carbon fiber bundle with the dispersion roll and removing the resulting fiber dust with a dust collector. [Embodiment 39] A manufacturing method according to Embodiment 37, further comprising dispersing the chopped carbon fiber bundle with the dispersion roll and removing the resulting fiber dust with a dust collector, wherein a suction port connected to the dust collector is provided on either the wall of the booth or inside the booth, or both. [Embodiment 40] A manufacturing method according to any one of Embodiments 35 to 39, further comprising applying a loosening treatment to the continuous carbon fiber bundle before cutting it with the chopper. [Embodiment 41] A manufacturing method according to Embodiment 40, wherein the loosening process includes piercing the continuous carbon fiber bundle with a projection. [Embodiment 42] A manufacturing method according to Embodiment 41, wherein a roll with protrusions is used for the loosening process. [Embodiment 43] A manufacturing method according to any one of Embodiments 40 to 42, wherein the loosening process includes bending the continuous carbon fiber bundle. [Embodiment 44] A manufacturing method according to Embodiment 43, wherein the loosening process uses a gear pair consisting of two gears that mesh with each other and may each be a spur gear.

[0049] [Embodiment 45] A manufacturing apparatus for carbon fiber sheet molding compound, comprising: a chopper positioned above the travel path of a carrier film; a guide tube for passing a continuous carbon fiber bundle drawn from a package and sent to the chopper; and a bundle loosener positioned upstream of the guide tube for loosening the continuous carbon fiber bundle. [Embodiment 46] A manufacturing apparatus according to Embodiment 45, wherein the bundle loosening device includes means for piercing the continuous carbon fiber bundle with a projection. [Embodiment 47] A manufacturing apparatus according to Embodiment 46, wherein the bundle loosening device includes a roll with protrusions. [Embodiment 48] A manufacturing apparatus according to any one of embodiments 45 to 47, wherein the bundle loosening device includes means for bending the continuous carbon fiber bundle. [Embodiment 49] A manufacturing apparatus according to Embodiment 48, wherein the bundle loosening device includes a gear pair consisting of two gears that mesh with each other, each of which may be a spur gear. [Embodiment 50] A manufacturing apparatus according to any one of embodiments 45 to 49, further comprising a rotationally driven dispersion roll for dispersing chopped carbon fiber bundles produced by cutting the continuous carbon fiber bundles with the chopper. [Embodiment 51] A manufacturing apparatus according to Embodiment 50, wherein the main part of the dispersion roll is arranged inside a booth, and a chute for guiding the chopped carbon fiber bundle is provided in an opening in the ceiling of the booth. [Embodiment 52] A manufacturing apparatus according to Embodiment 51, wherein a suction port connected to a dust collector is provided on either the wall of the booth or inside the booth, or both. [Embodiment 53] A manufacturing apparatus according to any one of embodiments 45 to 52, wherein at least one partition divides the space into a plurality of regions along the T direction from which the chopped carbon fiber bundles, produced by cutting the continuous carbon fiber bundles with the chopper, fall toward the travel path. [Embodiment 54] The manufacturing apparatus according to Embodiment 53, wherein at least one partition is made of metal and is grounded. [Embodiment 55] A manufacturing apparatus according to any of Embodiments 45 to 54, wherein the length of the guide tube is 3 m or more, and may be 5 m or more or 7 m or more.

[0050] [Embodiment 56] A carbon fiber sheet molding compound manufacturing apparatus comprising a chopper positioned above the travel path of a carrier film, and a bundle loosening device for loosening continuous carbon fiber bundles drawn out of a package and sent to the chopper, wherein the distance from the bundle loosening device to the chopper along the travel path of the continuous carbon fiber bundles is greater than 3m, greater than 5m, or greater than 7m. [Embodiment 57] A manufacturing apparatus according to Embodiment 56, wherein the bundle loosening device includes means for piercing the continuous carbon fiber bundle with a projection. [Embodiment 58] A manufacturing apparatus according to Embodiment 57, wherein the bundle loosening device includes a roll with protrusions. [Embodiment 59] A manufacturing apparatus according to any one of embodiments 56 to 58, wherein the bundle loosening device includes means for bending the continuous carbon fiber bundle. [Embodiment 60] A manufacturing apparatus according to Embodiment 59, wherein the bundle loosening device includes a gear pair consisting of two gears, each of which may be a spur gear that meshes with the other. [Embodiment 61] A manufacturing apparatus according to any one of embodiments 56 to 60, further comprising a rotationally driven dispersion roll for dispersing chopped carbon fiber bundles produced by cutting the continuous carbon fiber bundles with the chopper. [Embodiment 62] A manufacturing apparatus according to Embodiment 61, wherein the main part of the dispersion roll is arranged inside a booth, and a chute for guiding the chopped carbon fiber bundle is provided in an opening in the ceiling of the booth. [Embodiment 63] A manufacturing apparatus according to Embodiment 62, wherein a suction port connected to a dust collector is provided on either the wall of the booth or inside the booth, or both. [Embodiment 64] A manufacturing apparatus according to any one of embodiments 56 to 63, wherein at least one partition divides the space into a plurality of regions along the T direction from which the chopped carbon fiber bundles, produced by cutting the continuous carbon fiber bundles with the chopper, fall toward the travel path. [Embodiment 65] The manufacturing apparatus according to Embodiment 64, wherein at least one partition is made of metal and is grounded. [Embodiment 66] A manufacturing apparatus according to any one of embodiments 56 to 65, further comprising a guide tube for passing a continuous carbon fiber bundle through which the chopper is fed, and wherein the bundle loosening device is positioned upstream of the guide tube.

[0051] [Embodiment 67] A carbon fiber sheet molding compound manufacturing apparatus comprising: a chopper positioned above the travel path of a carrier film; a bundle loosening device for loosening continuous carbon fiber bundles sent to the chopper; and a rotationally driven dispersion roll for dispersing chopped carbon fiber bundles resulting from cutting the continuous carbon fiber bundles in the chopper. [Embodiment 68] A manufacturing apparatus according to Embodiment 67, wherein the dispersion roll is arranged inside a booth, and a chute for guiding the chopped carbon fiber bundle is provided in an opening in the ceiling of the booth. [Embodiment 69] A manufacturing apparatus according to Embodiment 68, wherein a suction port connected to a dust collector is provided on either the wall of the booth or inside the booth, or both. [Embodiment 70] A manufacturing apparatus according to any one of embodiments 67 to 69, wherein the bundle loosening device includes means for piercing the continuous carbon fiber bundle with a projection. [Embodiment 71] A manufacturing apparatus according to Embodiment 70, wherein the loosening device includes a roll with protrusions. [Embodiment 72] A manufacturing apparatus according to any one of embodiments 67 to 71, wherein the loosening process includes means for bending the continuous carbon fiber bundle. [Embodiment 73] A manufacturing apparatus according to Embodiment 72, wherein the loosening device includes a gear pair consisting of two gears that mesh with each other, each of which may be a spur gear. [Embodiment 74] A manufacturing apparatus according to any one of embodiments 67 to 73, wherein at least one partition divides the space in which the chopped carbon fiber bundle falls toward the travel path into a plurality of regions along the T direction. [Embodiment 75] The manufacturing apparatus according to Embodiment 74, wherein at least one partition is made of metal and is grounded.

[0052] [Embodiment 76] A carbon fiber sheet molding compound manufacturing apparatus comprising a chopper positioned above a travel path of a carrier film, and at least one partition made of metal and grounded, wherein the at least one partition divides the space into a plurality of regions along the T direction into which chopped carbon fiber bundles, produced by cutting a continuous carbon fiber bundle in the chopper, fall toward the travel path. [Embodiment 77] A manufacturing apparatus according to embodiment 76, further comprising a rotationally driven dispersion roll for dispersing the chopped carbon fiber bundle. [Embodiment 78] A manufacturing apparatus according to Embodiment 77, wherein the main part of the dispersion roll is arranged inside a booth, and a chute for guiding the chopped carbon fiber bundle is provided in an opening in the ceiling of the booth. [Embodiment 79] A manufacturing apparatus according to Embodiment 78, wherein a suction port connected to a dust collector is provided on either the wall of the booth or inside the booth, or both. [Embodiment 80] A manufacturing apparatus according to any one of embodiments 76 to 79, further comprising a bundle loosening device for loosening the continuous carbon fiber bundle before cutting with the chopper. [Embodiment 81] A manufacturing apparatus according to Embodiment 80, wherein the bundle loosening device includes means for piercing the continuous carbon fiber bundle with a projection. [Embodiment 82] A manufacturing apparatus according to Embodiment 81, wherein the bundle loosening device includes a roll with protrusions. [Embodiment 83] A manufacturing apparatus according to any one of embodiments 80 to 82, wherein the bundle loosening device includes means for bending the continuous carbon fiber bundle. [Embodiment 84] A manufacturing apparatus according to Embodiment 83, wherein the bundle loosening device includes a gear pair consisting of two gears that mesh with each other, each of which may be a spur gear. [Embodiment 85] A manufacturing apparatus according to any of Embodiments 45 to 84, wherein the carbon fiber sheet molding compound is obtained by impregnating a random mat consisting of chopped carbon fiber bundles with a paste consisting of a thermosetting resin composition.

[0053] [Embodiment 86] A manufacturing method according to any one of Embodiments 1 to 44, further comprising: applying a portion of the paste to one side of the carrier film before forming the random mat on the carrier film; overlapping another carrier film, on which the other portion of the paste has been applied to one side, with the random mat in between, on the carrier film to form a laminate; and compressing the laminate for the impregnation. [Embodiment 87] A method for manufacturing carbon fiber sheet molding compound using a manufacturing apparatus according to any of Embodiments 45 to 85.

[0054] 3. Experimental Results The results of the experiments conducted by the inventors are described below. Using a CF-SMC manufacturing apparatus equipped with a disperser positioned above the carrier film's travel path, a chopper positioned above the disperser, multiple guide tubes for passing continuous carbon fiber bundles to the chopper, and a gear pair positioned one at a time upstream of each guide tube, a random mat consisting of chopped carbon fiber bundles was deposited on a carrier film that had not been coated with resin paste. More detailed instructions are provided below.

[0055] Forty packages were prepared, each containing a continuous carbon fiber bundle with 15K filaments wound onto a bobbin. The continuous carbon fiber bundles drawn from each package were passed between two spur gears forming a gear pair, and then sent to a chopper through a single guide tube. Each gear pair consisted of two spur gears, both made of SUS304 stainless steel. The tooth width (length of the teeth in the axial direction of the gear) was 20 mm, the tooth height was 3.4 mm, the diameter of the tooth apex was 48 mm, and the length obtained by dividing the circumference of the tooth apex by the number of teeth was 5.0 mm. No mechanism was provided to actively rotate the spur gears.

[0056] In each gear pair, two spur gears were meshed together with a distance of 46 mm between the axes. The two spur gears rotated passively as a continuous bundle of carbon fibers, which was interlocked between them, was pulled by a chopper. The guide tubes were polyethylene tubes with an outer diameter of 20 mm and an inner diameter of 14 mm, and their lengths ranged from 3 m to 6 m. Therefore, each continuous carbon fiber bundle traveled more than 3 m from the time it was processed by the gear pair until it was cut by the chopper.

[0057] The disperser consisted of two pin rolls, each with a rotation axis parallel to the T-direction. The two pin rolls had the same configuration, with a cylinder diameter of 120 mm and pins arranged on the cylinder surface with diameters and lengths of 3 mm and 20 mm, respectively. The arrangement of pins on the cylinder surface was periodic, and the pin density was 1 cm². 2 The ratio was 0.42 pins per unit. The distance between the rotation axes of the two pin rolls was 150 mm. Both pin rolls of the disperser were rotated so that the pins moved from top to bottom on the side facing the other pin roller. The rotation speed of the two pin rolls was set to be the same.

[0058] Continuous carbon fiber bundles were cut by a chopper to a fiber length of approximately 1 inch (25.4 mm) after cutting, resulting in chopped carbon fiber bundles. The chopped carbon fiber bundles were dispersed using a disperser and dropped onto a carrier film traveling at a linear speed of 5 m / min. The dropped chopped carbon fiber bundles accumulated on the carrier film, forming a random mat. From the random mat, an area of ​​approximately 21 cm x 30 cm deposited near the center line of the carrier film was selected, and the weight of all chopped carbon fiber bundles (more than 300 pieces) contained in that area was measured. The weight-average number of filaments calculated based on this weight measurement was defined as the average number of filaments of chopped carbon fiber bundles in the random mat.

[0059] Table 1 below shows the average number of filaments in chopped carbon fiber bundles in random mats obtained by rotating the pin roll of the disperser at rotational speeds of 800 rpm, 1000 rpm, 1250 rpm, and 1500 rpm. Table 1 also shows the average number of filaments in chopped carbon fiber bundles in random mats formed in the same manner except that continuous carbon fiber bundles were not treated with gear pairs.

[0060] [Table 1]

[0061] Although the present invention has been described above with reference to specific embodiments, each embodiment is presented as an example and does not limit the scope of the present invention. Each embodiment described herein can be modified in various ways within the scope in which the effects of the invention are achieved, and can be combined with features described in other embodiments to the extent that is feasible. [Industrial applicability]

[0062] Carbon fiber sheet molding compounds produced using the manufacturing method or apparatus according to the embodiment can be suitably used in the manufacture of CFRP parts used in various transportation equipment or industrial equipment. Examples of transportation equipment as used herein include, but are not limited to, automobiles, ships, railway vehicles, manned aircraft, and unmanned aircraft. [Explanation of Symbols]

[0063] 1 Chopper 2a First coating machine 2b Second coating machine 3 Impregnation machine 10 Continuous carbon fiber bundles 20 Chopped carbon fiber bundles 30 Random Mats 41, 42 Paste 51 First Carrier Film 52 Second Carrier Film 60 Laminates BL Bundle Loosener GT Guide Tube GR Guide Roll

Claims

1. The process involves cutting a continuous carbon fiber bundle with a chopper to create chopped carbon fiber bundles, which are then dropped onto a moving carrier film to form a random mat. The random mat is impregnated with a paste made of a thermosetting resin composition, The continuous carbon fiber bundle is loosened before being cut by the chopper, The chopped carbon fiber bundles are dispersed by a rotationally driven dispersion roll before being dropped onto the carrier film, Includes, A method for manufacturing a carbon fiber sheet molding compound, wherein the loosening process uses a gear pair consisting of two gears that mesh with each other, each of which may be a spur gear.

2. Setting up a booth and placing the main part of the aforementioned dispersion roll inside it, A chute is used to guide the chopped carbon fiber bundle into an opening provided in the ceiling of the booth, The manufacturing method according to claim 1, further comprising:

3. The manufacturing method according to claim 1, further comprising dispersing the chopped carbon fiber bundle with the dispersion roll and removing the resulting fiber dust with a dust collector.

4. The method further includes dispersing the chopped carbon fiber bundle with the dispersion roll while removing the resulting fiber dust with a dust collector, The manufacturing method according to claim 2, wherein a suction port connected to the dust collector is provided on either the wall of the booth or inside the booth, or both.

5. The manufacturing method according to claim 1, wherein the loosening process includes inserting a projection into the continuous carbon fiber bundle.

6. The manufacturing method according to claim 5, wherein a roll with protrusions is used in the loosening process.

7. The manufacturing method according to claim 1, further comprising dividing the space in which the chopped carbon fiber bundle falls toward the carrier film into a plurality of regions along the T direction by at least one partition.

8. The manufacturing method according to claim 7, wherein at least one of the partitions is made of metal and is grounded.

9. A chopper positioned above the track of the carrier film, A bundle loosening device for loosening continuous carbon fiber bundles sent to the chopper, A rotationally driven dispersion roll for dispersing the chopped carbon fiber bundles produced by cutting the continuous carbon fiber bundles with the chopper, It has, A manufacturing apparatus for carbon fiber sheet molding compound, wherein the bundle loosening device includes a gear pair consisting of two gears that mesh with each other, each of which may be a spur gear.

10. The manufacturing apparatus according to claim 9, wherein the dispersion rolls are arranged inside a booth, and a chute for guiding the chopped carbon fiber bundles is provided in an opening in the ceiling of the booth.

11. The manufacturing apparatus according to claim 10, wherein a suction port connected to a dust collector is provided on either the wall of the booth or inside the booth, or both.

12. The manufacturing apparatus according to claim 9, wherein the bundle loosening device includes means for piercing the continuous carbon fiber bundle with a projection.

13. The manufacturing apparatus according to claim 12, wherein the loosening device includes a roll with protrusions.

14. The manufacturing apparatus according to claim 9, wherein at least one partition divides the space in which the chopped carbon fiber bundle falls toward the travel path into a plurality of regions along the T direction.

15. The manufacturing apparatus according to claim 14, wherein at least one of the partitions is made of metal and is grounded.

16. The manufacturing apparatus according to claim 9, wherein the carbon fiber sheet molding compound is obtained by impregnating a random mat consisting of chopped carbon fiber bundles with a paste consisting of a thermosetting resin composition.

17. Before forming the random mat on the carrier film, a portion of the paste is applied to one side of the carrier film. A laminate is formed by layering another carrier film, on which the other portion of the paste is applied to one side, with the random mat in between, onto the carrier film, and The manufacturing method according to any one of claims 1 to 8, further comprising compressing the laminate for the impregnation.

18. A method for manufacturing a carbon fiber sheet molding compound, using the manufacturing apparatus described in any one of claims 9 to 16.

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