JP5311444B2 - Manufacturing method of resin prepreg, fiber sheet for resin prepreg, resin prepreg and composite material thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a resin prepreg in which an industrial-quality thermoplastic resin prepreg can be produced in a simple production apparatus and in a short production time, the thermoplastic resin prepreg being excellent in the resin impregnation state, the homogeneity of reinforced fiber orientation, and the adhesion state between resin and reinforcing fiber. <P>SOLUTION: A carbon fiber sheet 1 is subjected to sewing by a heat-resistant thread 2 with a predetermined seam length, sewing length, and sewing interval in the direction perpendicular to the fiber direction. Then, the sewn carbon fiber sheet is immersed in acetone to remove a sizing agent and a coupling agent on the surface of the fiber bundle to obtain a continuous reinforced fiber sheet 10. Optionally, a coupling agent to improve the adhesion between fiber and resin is added to the fiber surface. Then, the continuous reinforced fiber sheet 10 and a polycarbonate sheet 4 are laminated, heated and pressurized, thereby pressure-impregnating the polycarbonate resin between the fibers to obtain a polycarbonate-carbon fiber prepreg. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a method for producing a resin prepreg, a fiber sheet for resin prepreg, a resin prepreg, and a composite material thereof. More specifically, a thermoplastic resin prepreg having excellent industrial quality in the impregnation state of the resin, the uniformity of the reinforcing fiber orientation and the adhesive state of the resin and the reinforcing fiber is manufactured with a simple manufacturing facility and in a short manufacturing time. It is possible to secure the handling of the opened dry reinforcing fiber sheet and impregnate the resin when laminating a plurality of dry reinforcing fiber sheets and then impregnating the thermosetting resin by RTM (= Resin Transfer Molding) The present invention relates to a method for producing a thermosetting resin prepreg capable of achieving improvement in property, a fiber sheet for resin prepreg, a resin prepreg, and a composite material thereof.

  Engineering plastics, which are thermoplastic resins, are highly recyclable, have high dimensional accuracy, and have excellent material properties such as high impact resistance, and are inexpensive, and their applications are automobiles, electrical equipment, optical equipment, IT-related And so on. As the name suggests, a thermoplastic resin can be melted by heating and the shape thereof can be easily deformed. Therefore, a molded product is generally manufactured by heating and rolling. On the other hand, the rigidity of a thermoplastic resin alone is lower than that of a metal / non-metallic material, and the rigidity can be improved to a level that can be used as a structural material by combining with a reinforcing fiber. Such a thermoplastic resin composite material, for example, compared to an epoxy resin composite material used in aircraft, if the same reinforcing fiber is used together, it has better strength and rigidity, but better recycling It becomes the composite material which has property. However, the thermoplastic resin has a high viscosity even when heated and melted due to its polymer structure. For example, polycarbonate and acrylonitrile butadiene styrene resin (hereinafter referred to as “ABS”) have high impact resistance in correlation with the high viscosity. Get higher. For this reason, the production of a thermoplastic resin composite material in which a continuous reinforcing fiber is impregnated with a thermoplastic resin is carried out with simple equipment, compared with the case of using a resin having an extremely low viscosity such as epoxy. It is not easy because it is difficult to ensure industrial quality. For this reason, the distribution of short fiber reinforced type and long fiber reinforced type composite materials produced by chopping glass fibers and carbon fibers and mixing them with thermoplastic is currently common.

  However, with respect to the method for producing a continuous fiber reinforced thermoplastic resin composite material, various production techniques have already been developed and numerous patents have been established. In general, a composite material structure manufactured using a thermoplastic resin and continuous reinforcing fibers is manufactured using a thermoplastic resin prepreg as an intermediate material. The reason for this is that it is possible to meet the rigidity requirement by manufacturing a prepreg laminate for the rigidity requirement of the structure to which the composite material is applied, that is, the composite material by prepreg can be designed. Is mentioned. A thermoplastic resin prepreg is generally produced in a sheet form by impregnating a continuous reinforcing fiber with a thermoplastic resin and aligning them in one direction. A plurality of the prepregs are stacked while changing the fiber direction, heated to melt the resin, and then pressurized to produce a composite material.

  As for existing patents relating to thermoplastic resin composite materials, there are those relating to the production of thermoplastic resin prepregs and methods for producing thermoplastic resin composite material structures using these prepregs. A general thermoplastic resin prepreg is manufactured by laminating a resin sheet on a continuous fiber sheet that is aligned in one direction, and melting the resin while applying tension to the fiber sheet so that the alignment (orientation) of the fiber bundle is not disturbed. The resin is melted by heating to a temperature higher than that, and the fiber sheet is impregnated with resin by pressurization. Here, the superiority or inferiority of the industrial quality of the thermoplastic resin prepreg is determined by the difference in the production method. Specifically, the industrial quality of the prepreg production is evaluated by evaluating the impregnation state of the resin (the presence or absence of voids), the uniformity of the reinforcing fiber orientation, and the adhesion state of the resin and the reinforcing fiber.

  In the polycarbonate and the like used for the thermoplastic resin prepreg of the examples of the present invention described later, the resin viscosity and the mechanical properties of the resin are correlated. For example, the high impact resistance, which is also a characteristic of polycarbonate, is proportional to the high viscosity. Such a resin has a high viscosity even when heated to a molding temperature recommended by the manufacturer. For example, impregnation of a fiber bundle of polycarbonate is extremely difficult as compared with an epoxy resin or the like. For this reason, while it is excellent in mechanical characteristics, when manufacturing a prepreg with a thermoplastic resin with high viscosity, the industrial quality of the prepreg is established by the manufacturing method concerning various patents.

  As for the related art relating to the production of a thermoplastic resin prepreg, for example, a method of aligning fibers while applying tension and impregnating the resin with reinforcing fibers on the tape (see, for example, Patent Document 1), reinforcing a metal plate. A method in which fibers and a thermoplastic resin are wound and hot-pressed (for example, see Patent Document 2), a method in which a resin is powdered and impregnated into the fiber (for example, see Patent Document 3), a fiber-reinforced reinforcing fiber sheet A method in which a thermoplastic resin nonwoven fabric made of thermoplastic resin fibers is stacked and heated while being heated (see, for example, Patent Document 4), and reinforcing fibers and matrix fibers made of thermoplastic resin are mixed while being opened. Then, this is spread into a sheet and heated and fused to produce a prepreg (see, for example, Patent Document 5), and the reinforcing fibers are aligned in one direction to form a sheet. Method of the reinforcing fiber sheet is attached to and introduced into the processing bath containing the thermoplastic resin resin (e.g., see Patent Document 6.), And the like.

  As a general thermoplastic resin prepreg manufacturing method, when thermoplastic resin is heated and melted and pressurized and impregnated into continuous fibers, if the viscosity of the resin is high, the line speed during production is slowed down and sufficient resin impregnation It is necessary to secure time, and when the resin viscosity is extremely high, impregnation failure occurs, and the prepreg contains many voids. In order to shorten the line speed, if the pressure pressure is increased at a stretch to increase the resin impregnation speed, the interval between some of the aligned continuous fibers increases, resulting in a decrease in the quality of the prepreg. . Further, in this manufacturing method, it is necessary to apply high tension to the fiber bundle in order to keep the continuous fibers aligned during pressure impregnation, and cutting is particularly likely to occur in high-rigid fibers such as carbon fibers. Furthermore, since the resin is impregnated while applying a high tension, the cost of equipment during prepreg production is increased. On the other hand, if the viscosity of the resin at the time of melting is low, impregnation is possible at a high speed, but a resin rich in resin fluidity has a low molecular weight, and the mechanical properties of the resin itself are lowered. For this reason, the low-viscosity thermoplastic resin composite material has lower mechanical properties than the high-viscosity resin. In addition, the method of impregnating the powdered thermoplastic resin by adhering it to the reinforcing fiber sheet makes it difficult to produce the thermoplastic resin in a homogeneous powder form, resulting in an increase in the cost of the base material. It is also difficult to adjust the adhesion amount of the resin. The manufacturing method that requires the thermoplastic resin to be fibrous is similarly expensive in terms of cost. The method of making a thermoplastic resin into a solution and impregnating the reinforcing fiber material has a problem that the types of resins and solvents that can be used are limited, and further includes a thermoplastic resin in a state where tension is applied to the reinforcing fiber sheet. Therefore, a production line in which resin impregnation is performed by immersing in a treatment bath of the solution to be used is necessary, and similarly, the cost of the equipment is unavoidable.

  In continuous reinforcing fiber sheets such as glass fiber and carbon fiber, sizing treatment is applied to the fiber substrate in the manufacturing process for the purpose of improving the convergence and handling of single fibers and maintaining the orientation of the fiber sheet during transportation. It has been subjected. Control of the adhesion interface is important for improving the adhesion between the resin that is the base material of the composite material and the reinforcing fibers. Control of this interface refers to the formation of a chemical bond between the adhesive surface of the resin and the reinforcing fiber, improvement of the wettability of the resin to the fiber surface, improvement of the compatibility between the fiber surface and the resin, and the like. Since the control of these interfaces is performed by a coupling agent, a general continuous reinforcing fiber sheet is chemically treated with a sizing agent and a coupling agent. (Coupling agent: A chemical substance that has the effect of improving mechanical strength by reacting or interacting with both the filler of the composite material and the resin)

  On the other hand, details of the fiber surface treatment of the commercially available reinforcing fiber sheet have not been disclosed, and the interface control effect between the thermoplastic resin and the reinforcing fiber brought about by the coupling agent is unknown to many users. In the case of a reinforced fiber and a thermoplastic resin to which a general coupling agent for epoxy resin is added, the adhesiveness may deteriorate in some cases. Moreover, the handling property of the fiber sheet from which the fiber has been opened by removing the sizing agent is extremely deteriorated. On the other hand, in order to improve the adhesion between the thermoplastic resin and the reinforcing fiber, the resin / fiber bonding area is increased as much as possible during the resin impregnation, and a high-viscosity resin is fed into the fiber bundle to surround each filament. It is important to feed resin into the tank. For this reason, it is effective to perform fiber impregnation by opening the fiber bundle group of the reinforcing fiber sheet. However, when the resin viscosity is high, the interval between some of the aligned continuous fibers is widened. Reduce the quality of the prepreg. In the case of unopened fibers, the efficiency of impregnation is deteriorated. As a result, impregnation failure occurs and mechanical properties are deteriorated.

  For the above reasons, in the production of thermoplastic resin composites with high mechanical properties, a high-viscosity resin is impregnated reliably and quickly without disturbing the fiber orientation in the opened continuous strong fiber sheet. Therefore, it is considered effective to apply a method for producing a thermoplastic resin prepreg. For a method of opening the reinforcing fiber bundle and impregnating the thermoplastic resin with the thermoplastic fiber bundle, a method of opening the bundled fiber bundle by mechanical impact and then impregnating the molten thermoplastic resin (see, for example, Patent Document 8). ), And a method of impregnating the spread fiber sheet by assembling and impregnating a thermoplastic resin sheet in a hot melt state after opening and closing the bundle group that is fed into a sheet shape (for example, patent document) 9) is known. However, in any of the methods, it is necessary to apply excessive tension to the continuous fiber sheet as a solution to the extreme deterioration of the handleability of the reinforcing fiber sheet after opening and the maintenance of the uniformity of fiber orientation during resin impregnation. In addition, the equipment becomes complicated and expensive.

  As described above, the industrial quality of a thermoplastic resin prepreg is evaluated by examining the impregnation state of the resin (the presence or absence of voids), the uniformity of the reinforcing fiber orientation, the adhesive state of the resin and the reinforcing fiber, and the like. . In addition, in order to reduce the cost of materials, it is easy to use low-cost base materials that can be used for currently available thermoplastic resin prepregs, such as resin sheets and general continuous reinforcing fiber sheets. It is indispensable to manufacture with the equipment. Therefore, if it is possible to provide a method for producing a wide range of thermoplastic resin prepregs with good industrial quality in a short production time and without the cost of facilities and base materials, a composite material using this prepreg can be manufactured at a low cost. As a material with excellent performance, it can be expected to be used in the fields of automobiles, architecture, aircraft, etc.

By the way, as a result of recent research on laminated composite structures made of thermosetting resins such as epoxy and carbon fibers, which are common in composite structures, the strength increases as each layer of the laminated structure is thinned. From the experimental results, it is clear that a laminated composite material with a thin layer has been developed. As a method of reducing the thickness of one layer, in order to make a prepreg thin, a reinforcing fiber bundle was opened and thinned in a direction perpendicular to the fiber (reducing the amount of fibers per unit area). It is common for sheets to be used.
In recent years, RTM (resin-impregnated molding method) has been actively researched and developed as a low-cost composite structure molding method, and the laminated composite structure is composed of a plurality of dry reinforcing fiber sheets that are not impregnated with resin at all. Then, it is manufactured by a method in which a thermosetting resin is impregnated and then heated to cure the resin. In the case of such a manufacturing method, in order to reduce the thickness of the laminated composite material, it is considered that a fiber opening process is performed to make the dry reinforcing fiber sheet thinner. However, the opened fiber sheet has extremely poor handling properties and is not suitable for transportation. Further, when a composite material structure is manufactured by laminating dry fiber sheets whose thickness is reduced by opening the fiber, it is necessary to increase the number of layers in order to secure the thickness of the composite material. On the other hand, in laminated composite materials, reinforcing fiber sheets are generally laminated while changing the fiber direction, and it is known that the difference in fiber orientation angle for each layer prevents impregnation of resin. For this reason, in order to manufacture a laminated composite structure having a reduced thickness by RTM, securing the handling property of the opened reinforcing fiber sheet and improving the resin impregnation property become problems.

Japanese Patent Laid-Open No. 63-027208 Japanese Patent Application Laid-Open No. 07-308991 Japanese Patent Laid-Open No. 17-239843 Japanese Patent Laid-Open No. 15-165851 Japanese Patent Laid-Open No. 06-322159 JP-A-17-255927 Japanese Patent Laid-Open No. 06-116851 Japanese Patent Laid-Open No. 17-029912

As described above, in order to obtain a thermoplastic resin prepreg having excellent industrial quality in the resin impregnation state, the uniformity of the reinforcing fiber orientation and the adhesion state between the resin and the reinforcing fiber, the production of the conventional thermoplastic resin prepreg In technology, the process of processing a thermoplastic resin into a special form such as powder or fiber in advance, equipment that applies high tension to the reinforcing fiber, equipment that impregnates the resin while applying high tension after opening the reinforcing fiber Alternatively, complicated equipment for immersing the fiber sheet in the solution bath of the thermoplastic resin is required, and as a result, there is a problem that the cost is increased. In terms of production time, the conventional thermoplastic resin prepreg production technique requires a sufficient resin impregnation time.
On the other hand, in order to obtain a thermosetting resin prepreg by laminating a plurality of thin dry reinforcing fiber sheets, impregnating the thermosetting resin with RTM, and then curing the thermosetting resin by heating. Ensuring the handleability of the fine dry reinforcing fiber sheet and improving the resin impregnation are problems.
Accordingly, the object of the present invention has been devised in view of the above circumstances, and with a simple manufacturing facility and in a shorter manufacturing time than conventional ones, the impregnation state of the resin, the uniformity of the reinforcing fiber orientation, and the resin and the reinforcing fiber Can produce a thermoplastic resin prepreg with excellent industrial quality in the adhesive state of the above, and after the lamination of a plurality of dry reinforcing fiber sheets, the dry opened fiber when impregnated with a thermosetting resin by RTM It is providing the manufacturing method of the thermosetting resin prepreg which can achieve the ensuring of the handleability of this reinforced fiber sheet, and the improvement of resin impregnation, the fiber sheet for resin prepregs, the resin prepreg, and its composite material.

  In one aspect of the present invention, a generally circulated thermoplastic resin sheet (film) is superposed on the fiber sheet that is generally distributed, after the stitching process and the fiber opening process described below are performed, and then heated. -A thermoplastic resin prepreg is manufactured by impregnating the resin sheet by pressurization.

  The fiber sheet used in the method for producing the thermoplastic resin prepreg is not subjected to fiber surface treatment with a specific sizing agent or coupling agent. For example, for an epoxy resin which is a general continuous reinforcing fiber sheet Those subjected to the above chemical treatment may be used. As the fiber itself, a sheet formed by aligning carbon fiber, glass fiber, ceramic fiber, aramid fiber and the like in one direction is used. Assuming that the direction perpendicular to the direction in which the fibers are aligned is the width direction, the length in the width direction is not particularly limited because it is essentially attributable to the production method of the present invention, and the hot used for prepreg production. Any length may be used as long as it is smaller than the size of a hot plate such as a press.

  First, a stitching process is performed on the fiber sheet. For example, an industrial sewing machine is used as an apparatus used for performing the suturing process. The sewing thread used for the stitching process is not particularly limited, but a heat-resistant thread having a heat resistance equal to or higher than the melting temperature of the resin is used in a heating / pressurizing process in which a thermoplastic resin is melted and impregnated between fibers. It is desirable to do. The heat-resistant yarn (suture) is preferably made of high-strength fiber because it plays the role of maintaining the fiber orientation during resin impregnation by heating and pressing. In addition, since a gap is formed at a place where the suture thread passes through the continuous reinforcing fiber sheet subjected to the stitching process, it is desirable that the diameter of the suture thread is thin in terms of material strength. The stitching method, stitch length, and stitch interval during the suturing process are not particularly defined.

  However, in the fiber sheet subjected to the suturing process, the region where the suture thread passes through the fiber sheet is an inflow path of the molten resin into the fiber bundle. In the present invention, when the resin viscosity is extremely high, or when the resin impregnation is performed below the molding temperature recommended by the manufacturer for each resin, or when the resin impregnation speed is increased, the suture thread (sewing thread) ), The stitching method, the stitch length, and the stitching interval can be adjusted to improve the resin impregnation property.

  Next, the fiber sheet subjected to the stitching process is subjected to a fiber opening process. The fiber opening treatment refers to fiber opening and removal of a coupling agent or sizing agent that does not provide an interface control effect for the thermoplastic resin to be impregnated into the continuous reinforcing fiber sheet. . The method for the fiber opening treatment is not particularly specified, but the fiber bundle is sufficiently opened and the fiber surface coupling agent and sizing agent can be removed. Although the effect of maintaining the handling property and the uniformity of fiber orientation by the sizing agent is lost by this fiber opening treatment, the above-described suture instead provides the same effect. As a result of this opening process, the thermoplastic resin flows around each filament, whereby the adhesion between the fiber and the resin is improved by a physical effect. In order to further improve the adhesion, a coupling agent capable of obtaining an interface control effect is adhered to the fiber surface with respect to the thermoplastic resin sheet and the fiber sheet to be impregnated. In the present invention, the chemical treatment and the opening treatment are collectively referred to as “opening treatment on the fiber sheet”, and the “opening treatment” described in the above-mentioned claims includes the fiber sheet and the thermoplastic resin. In order to improve the physical and chemical adhesion with the fiber sheet.

  After the thermoplastic resin sheet is disposed only on one side or both sides of the continuous reinforcing fiber sheet subjected to the stitching process and the fiber opening process, the laminate is heated at a temperature higher than the melting temperature of the thermoplastic resin. After the resin is melted, a thermoplastic resin prepreg is manufactured by pressurizing and impregnating the resin and cooling. This thermoplastic resin prepreg manufacturing apparatus includes preheating means for preheating the laminate to a temperature higher than the melting temperature of the thermoplastic resin, and pressurizing to press the preheated laminate to form a thermoplastic resin prepreg. It may be composed of means. As a manufacturing apparatus that satisfies this condition, a simple hot press can be employed.

  In the method for producing the thermoplastic resin prepreg of the present invention, it is not particularly necessary to give tension or the like for maintaining the fiber orientation to the continuous reinforcing fiber sheet. The stitching process suppresses disturbance of fiber orientation and promotes inflow of resin. In addition, treatment such as fiber opening also promotes the inflow of the resin and, in addition, improves the adhesion between the fiber and the resin physically and chemically. In the present invention, the basis that the thermoplastic resin prepreg having excellent industrial quality is obtained at low cost is based on the simplicity of the manufacturing apparatus used.

  On the other hand, as described above, the fiber sheet needs to be subjected to a stitching process, a fiber opening process, and the like, and there is a concern about an increase in cost due to this. However, the suturing process can be performed very easily with an industrial sewing machine or the like, and existing techniques can also be applied to the process such as opening. Accordingly, even when the continuous reinforcing fiber sheet according to the present invention is mass-produced, the problem of cost is considered to be very easy to solve because the fiber orientation is disturbed by the stitching process during the transportation of the fiber sheet. It is done. For this reason, as will be apparent from the embodiments of the present invention to be described later, there is no particular need for equipment for continuously performing the fiber opening treatment and the resin impregnation manufacturing process.

  Furthermore, the present inventors have found that the stepwise pressurization method is effective for impregnating the fiber sheet with a thermoplastic resin such as polycarbonate, through research efforts up to the invention of the above production method. It was. In this stepwise pressurization method, in order to suppress disturbance of the fiber orientation as much as possible, the molten thermoplastic resin is stepped from a low pressure to a high pressure step by step at a certain time interval. This is a method for producing a thermoplastic resin prepreg that slowly and surely flows into the fiber bundle. In particular, when the thermoplastic resin has a low molecular weight and a low viscosity at the time of melting, only this stepwise pressurization method is applied, so that a fiber sheet that has only been subjected to a treatment such as opening is also excellent in thermoplasticity. It has been confirmed in the literature (Evaluation of mechanical properties of carbon fiber unidirectional reinforced polypropylene, Vol. 32, No. 4 of the Japan Society for Composite Materials) that resin prepreg can be obtained. However, it can be inferred that there is a limit to shortening the manufacturing time of the prepreg only by applying the stepwise pressurization method. That is, if the applied pressure is increased in a short time, the resin is rolled on the surface of the fiber sheet before the resin flows into the fiber bundle, and the orientation of the opened fiber sheet is disturbed. However, in the production of a prepreg made of a reinforced fiber sheet and a thermoplastic resin subjected to a stitching process and a fiber opening process according to the present invention, by applying this stepwise pressing method, the resin is made into a fiber without disturbing the fiber orientation. The effect of impregnating in between can be supplementarily provided, and as a result, the production time of the prepreg can be shortened. Accordingly, such a manufacturing method is also included in the above claims.

  From the above, according to the method for producing a resin prepreg according to the present invention, the conditions for the stitching process and the fiber opening process applied to the fiber sheet described above and the melting temperature at the time of resin impregnation / maximum value of pressure / pressure increase The molding conditions of the process are optimal according to the mechanical properties such as the properties of the thermoplastic resin sheet and continuous reinforcing fiber sheet used for the thermoplastic resin prepreg (type of resin, type of fiber, etc.), production time, and material strength. You can select conditions.

  Also, a plurality of thermoplastic resin prepregs manufactured according to the present invention are laminated by alternately changing the fiber direction, and the laminate is heated to melt the resin and then pressurized to apply a thermoplastic resin composite material laminate. A board can be manufactured.

  In the above description, a thermoplastic resin is assumed as a matrix resin to be impregnated with pressure between fibers, but is not limited to a thermoplastic resin, and a thermosetting resin prepreg is impregnated and impregnated between fibers with a thermosetting resin. Can be manufactured.

Regarding the production of the thermoplastic resin or the thermosetting resin prepreg, the effects of the invention described below were obtained by subjecting the fiber sheet to a treatment such as stitching and opening.
1. Physical effect (1) By applying a stitching process to the fiber sheet, the fiber sheet orientation disorder after the fiber opening process is suppressed and the fiber orientation disorder during the resin impregnation by pressurization is suppressed. The resin inflow path is given to the fiber sheet.
(2) The fiber sheet is subjected to a treatment such as opening, thereby improving the resin impregnation property of the fiber sheet and improving the adhesion between the fiber and the resin.
2. Economic effect (1) Lowering the cost of resin prepreg by applying a commonly distributed thermoplastic resin sheet or thermosetting resin to a generally distributed fiber sheet (2) Simplifying manufacturing equipment, reducing cost Due to physical and economic effects, the present invention provides an excellent industrial quality thermoplastic resin prepreg or thermosetting resin prepreg with good resin impregnation state, uniformity of reinforcing fiber orientation and good adhesion state between resin and fiber. Can be provided at a low cost. In particular, the thermoplastic resin prepreg obtained by the present invention can be molded into composite structures of various shapes by placing in a mold and hot pressing as in the case of a conventional thermoplastic resin prepreg.

  Hereinafter, the present invention will be described in more detail with reference to embodiments shown in the drawings. Note that the present invention is not limited thereby.

  A carbon fiber unidirectional continuous sheet (SP systems, UT-C400, weight per unit: 400 g / sqm) was cut into a size of 250 mm in the fiber direction and 230 mm in the width direction to obtain a carbon fiber sheet. Next, using a heat-resistant yarn (Kuraray, Vectran, # 50) 2 with an industrial sewing machine (JUKI, DDL-9000S) for the carbon fiber sheet 1, the stitch length is 1.25mm, and the sewing interval (sewing interval) Was 20 mm, and was sutured so as to cross the entire area of 230 mm in width (= stitching length) in a direction perpendicular to the fiber. The way of sewing is lock stitching. Reverse stitching is not performed at the end of the fiber sheet. FIG. 1 shows a carbon fiber sheet 1 subjected to a suturing process. In addition to carbon fibers, it is also possible to use a fiber sheet in which reinforcing fibers such as glass fibers, aramid fibers, or ceramic fibers are aligned in one direction to form a sheet. In addition to Vectran, it is also possible to use a high-strength and high-rigidity heat-resistant yarn such as Nomex, Conex, Pyromex, Lastex, or Zylon.

  Next, the above-mentioned carbon fiber sheet 1 subjected to the suturing treatment is completely immersed in 350 ml of acetone (made by Wako Pure Chemical Industries, reagent special grade) for 60 minutes, once the acetone is completely evaporated, and further in 250 ml of acetone. For 60 minutes to remove the sizing agent and coupling agent on the surface of the fiber bundle. The feature of the treatment such as opening of the carbon fiber sheet using acetone is that the sizing agent and the coupling agent can be removed at the same time, and there is also a degreasing effect. In addition, it is possible to obtain a spread fiber sheet with less fiber fluffing than the mechanical fiber opening. FIG. 2 shows a carbon fiber sheet 3 that has been subjected to a stitching process, a fiber opening process, and the like. By performing the stitching process, the handleability of the carbon fiber sheet 3 is good even after opening, and the orientation of the carbon fiber sheet in one direction is maintained even during resin impregnation. Further, the passage of the suture thread (heat-resistant thread 2) in the carbon fiber sheet 3 becomes a resin inflow path. FIG. 3 is a schematic view of the continuous reinforcing fiber sheet 10 subjected to the stitching process and the fiber opening process according to the present invention. In this example, coupling agents such as silane, titanate, aluminate, zirconate and the like are not attached to the fiber bundle for controlling the adhesion interface between the polycarbonate and the carbon fiber. .

FIG. 4 is an explanatory view showing a method for producing a polycarbonate / carbon fiber prepreg according to an embodiment of the present invention.
Polycarbonate sheet 4 (manufactured by Teijin Chemicals, Panlite film, PC-2151 (clear)) as a thermoplastic resin sheet was cut out to 230 × 140 mm, and this polycarbonate sheet 4 was dried by a constant temperature dryer (110 ° C., 5 hours or more) ). A spacer (dam) 5 made of a thin aluminum plate is placed on a heat-resistant tape (with a width of 230 mm) against a pressure plate mold for molding a thermoplastic resin consisting of an upper heating / pressure plate 6 and a lower heating / pressure plate 7. Affixed and fixed to the lower heating / pressurizing plate 7 with Kapton tape). Next, the continuous reinforcing fiber sheet 10 that has been subjected to the above-described stitching processing and fiber opening treatment is disposed between the spacers 5 and 5 on the lower heating / pressurizing plate 7, and ends thereof are fixed with heat-resistant tape (not shown), A dried polycarbonate sheet 4 was placed thereon. It is understood that this is not a special method, and the polycarbonate sheet 4 is also simply laminated on one side of the continuous reinforcing fiber sheet 10 and is an extremely simple molding method. Moreover, the shaping | molding method (manufacturing method) by FIG. 4 is an example of the manufacturing method of the thermoplastic resin prepreg by the continuous reinforcement | strengthening fiber sheet 10 processed, such as a stitching process and fiber opening concerning this invention. In addition to polycarbonate, vinyl chloride, acrylonitrile butadiene styrene resin (ABS), polyethylene, polypropylene, polyamide, polyacetal, polybutylene terephthalate, polyimide, polyphenylene sulfide, polyether sulfone, or polyether ether ketone are used as the thermoplastic resin. Is possible.

  A hot press (manufactured by Toyo Seiki, mini-test press MP-S) as preheating means and pressurizing means was preheated to a molding temperature of 310 ° C. Next, a pressure plate mold for molding in which the polycarbonate sheet 4 was laminated on the continuous reinforcing fiber sheet 10 was placed in a hot press, and preheating was performed for 10 minutes. After the preheating, the continuous reinforcing fiber sheet 10 was impregnated with the polycarbonate sheet 4 by pressurization by a stepwise pressurization method. Regarding the pressure increase rate, the intervals of the pressure increase time were both 2 min. It should be noted that since the pressure increase is measured by a timer and the pressure is increased manually, a slight variation occurs in the pressure increase process. After the pressure was increased to 1.75 MPa, the hot press heating panel was switched off and the air was naturally cooled to 190 ° C. while maintaining the pressure level. When the temperature dropped to 190 ° C, it was further cooled to 120 ° C using the water-cooling function of the hot press and depressurized for demolding. A polycarbonate / carbon fiber prepreg (average thickness: 0.4 mm) was obtained by the molding method described above. The polycarbonate / carbon fiber prepreg as the thermoplastic resin prepreg obtained by the method of the present invention had no impregnation failure and no significant disturbance in fiber orientation, and was a good molded product. FIG. 5 shows the obtained polycarbonate / carbon fiber prepreg. FIG. 6 is an enlarged view of the obtained polycarbonate / carbon fiber prepreg. In this polycarbonate / carbon fiber prepreg, no large voids are particularly seen, and it can be confirmed that the polycarbonate / carbon fiber prepreg is in a good molded state. FIG. 7 shows a photomicrograph of the vicinity of the suture thread when the polycarbonate / carbon fiber prepreg is torn along the fiber direction. It can be seen that there is no impregnation failure around the suture.

Moreover, FIG. 8 is explanatory drawing which shows the pressurization process which impregnates a continuous reinforcing fiber sheet with resin. In Process 1, preheating is performed for 10 minutes, and then the pressurization interval is maintained at 2 min., Up to 0.25 MPa in increments of 0.0625 MPa, 0.25 to 0.75 MPa in increments of 0.125 MPa, and 0.75 to 1.75 MPa in increments of 0.25 MPa. This is a pressurizing process in which pressure is increased in 11 steps (total pressurization time = 32 min.).
Process 2 is a pressurizing step in which preheating is performed for 5 minutes, and then the pressure increase interval is maintained at 1 min., And pressure is increased in 9 steps of 0.125 MPa up to 0.75 MPa and 0.25 to 1.75 MPa in increments of 0.25 MPa ( Pressurization total time = 14 min.).
Process 3 is a pressurizing step in which preheating is performed for 3 minutes, and then the pressure increase interval is maintained at 1 min., And pressure is increased in 7 steps of 0.125 MPa up to 0.25 MPa and 0.25 to 1.75 MPa in 0.25 MPa steps ( Pressurization total time = 10 min.).

With respect to the polycarbonate / carbon fiber prepreg obtained by impregnating the polycarbonate sheet 4 into the continuous reinforcing fiber sheet 10 subjected to the stitching process at a stitching interval of 20 mm by the process 1, the molded state of the resin and the reinforcing fiber is used. Was confirmed to be good.
Further, the polycarbonate / carbon fiber prepreg obtained by impregnating the polycarbonate sheet 4 into the continuous reinforcing fiber sheet 10 subjected to the stitching process at a stitching interval of 10 mm by the process 2 is also used for the resin and the reinforcing fiber. It was confirmed that the molding state was good.
Further, with respect to the polycarbonate / carbon fiber prepreg obtained by impregnating the polycarbonate sheet 4 into the continuous reinforcing fiber sheet 10 subjected to the stitching process at a stitching interval of 10 mm by the process 3, the resin and the reinforcing fiber are also mixed. It was confirmed that the molding state was good.
However, in the same process 3, when the continuous reinforcing fiber sheet 10 subjected to the stitching process with the stitching interval extended to 20 mm was impregnated with the polycarbonate sheet 4, the molding state of the resin and the reinforcing fiber was poorly impregnated. .
Therefore, from the above test results, regarding the influence of the pressurization time and stitching interval on the molding of the resin and the reinforcing fiber, if the stitching interval is small, the impregnation property of the resin to the reinforcing fiber is improved, and if the pressurizing speed is slow, the reinforcing fiber It is considered that the impregnation property of the resin with respect to is improved.

  FIG. 9 is a graph showing the results of a static tensile test of the polycarbonate / carbon fiber prepreg according to the present invention. The specimen 1-3 (Specimen1-3) is a polycarbonate / carbon fiber prepreg obtained by impregnating the polycarbonate sheet 4 with the continuous reinforcing fiber sheet 10 having a stitching interval of 20 mm by the process 1 described above. This tensile test was performed by pulling a test piece of 180 mm × 25 mm × 3.5 mm with a tester at a test speed of 0.5 mm / min. Further, as a comparative example, a polycarbonate resin simple substance (PC) and an epoxy resin simple substance (Epoxy) were subjected to a tensile test under the same conditions. FIG. 9 shows a stress-strain curve at that time. As can be seen from this figure, the polycarbonate / carbon fiber prepreg according to the present invention has extremely high tensile strength and rigidity as compared with the polycarbonate resin alone.

  FIG. 10 is a graph showing the results of a compression test of a polycarbonate / carbon fiber prepreg according to the present invention. The specimen is a polycarbonate / carbon fiber prepreg obtained by impregnating the continuous reinforcing fiber sheet 10 having a stitching interval of 20 mm with the polycarbonate sheet 4 in the same manner as in FIG. The test was conducted by compressing a test piece of 80 mm × 25 mm × 3.5 mm with a tester at a test speed of 0.5 mm / min. In addition, as a comparative example, a compression test was performed under the same conditions for an epoxy / carbon fiber prepreg obtained by impregnating the continuous reinforcing fiber sheet 10 with an epoxy resin. FIG. 10 shows a stress-time curve at that time. As can be seen from this figure, in the polycarbonate / carbon fiber prepreg according to the present invention, sequential failure occurs, the compressive strength is higher than that of the epoxy / carbon fiber prepreg, and the energy absorption by the failure is also large.

  FIG. 11 is a graph showing the results of a bending test of the polycarbonate / carbon fiber prepreg according to the present invention. The specimen is a polycarbonate / carbon fiber prepreg obtained by impregnating the continuous reinforcing fiber sheet 10 having a stitching interval of 20 mm with the polycarbonate sheet 4 in the same manner as in FIG. In addition, in accordance with JIS K7074, the test is performed by applying a load (three-point bending) to one point of a 180 mm x 15 mm x 3.5 mm test piece simply supported at both ends, or a load (four-point bending) at two points. ) And bending at a test speed of 5 mm / min. FIG. 11 shows a stress-displacement curve at that time. As can be seen from the figure, in the polycarbonate / carbon fiber prepreg according to the present invention, sequential breakage occurs, and energy absorption due to breakage is large as in the compression test. The three-point bending strength and the four-point bending strength of the polycarbonate / carbon fiber prepreg according to the present invention were 561 MPa and 484 MPa, respectively.

  FIG. 12 is a photograph showing an observation result after a falling weight impact test of the polycarbonate / carbon fiber prepreg according to the present invention. As in FIG. 9, the specimen is a polycarbonate / carbon fiber prepreg obtained by impregnating the continuous reinforcing fiber sheet 10 having a stitching interval of 20 mm by the process 1 with the polycarbonate sheet 4. The test was performed by dropping a predetermined weight from a predetermined height on a test piece of 80 mm × 50 mm × 3.5 mm in accordance with JIS K7089. FIG. 12 shows the deformation state on the front and back surfaces of the polycarbonate / carbon fiber prepreg according to the present invention after each (energy conversion: 12J, 36J, 70J) impact test. As a comparative example, FIG. 13 shows the deformation state of the front and back surfaces of the epoxy / carbon fiber prepreg obtained by impregnating the above-mentioned continuous reinforcing fiber sheet 10 with an epoxy resin after 62.5 J drop weight impact is applied. It was. As can be seen from these figures, in the polycarbonate / carbon fiber prepreg according to the present invention, the amount of deformation of the front and back surfaces increases in proportion to the applied energy at the location where the impact is applied, but the front and back surfaces penetrate. Not as big as the deformation. For example, even at a location where a large energy of 70 J is applied, the deformation has not reached such a great extent that the front and back surfaces penetrate. On the other hand, in the case of an epoxy / carbon fiber prepreg, the front and back surfaces of the epoxy / carbon fiber prepreg are greatly deformed so that the front and back surfaces almost penetrate.

  FIG. 14 is a graph showing the load / energy history during each (energy conversion: 12J, 36J, 70J) impact test.

FIG. 15 is a photograph showing an internal observation result of a polycarbonate / carbon fiber prepreg obtained by applying the method for producing a resin prepreg of the present invention to a high-strength / high-elasticity carbon fiber.
In this figure, unidirectional carbon fiber substrate T800SC (SARTEX, 24K) is used as the carbon fiber, and after the above-described stitching treatment and fiber opening treatment, the polycarbonate resin is pressure impregnated by two different molding processes. FIG. 15 (a) shows the results of internal observation of the polycarbonate / carbon fiber prepreg at the time when the final pressure was 7 MPa, the total pressurization time was 10 min., And the molding temperature was 270 ° C. (B) is an internal observation result of a polycarbonate / carbon fiber prepreg by a molding process of final ultimate pressure = 2 MPa, total pressure time = 10 min., Molding temperature = 310 ° C.
The impregnation state of the polycarbonate / carbon fiber prepreg by the former molding process was good, but the resin impregnation state of the polycarbonate / carbon fiber prepreg by the latter molding process was not so good because there was an unimpregnated part. From these results, it was found that the impregnation state of the resin changed greatly by changing the conditions of the molding process. Therefore, it is considered that adjustment of the molding process conditions is necessary if the manufacturer and molding apparatus of the material used are different.

FIG. 16 is a graph showing the influence of the applied pressure and molding temperature on the thickness of the resin prepreg. As the carbon fiber, a unidirectional carbon fiber substrate T800SC (manufactured by SARTEX, 24K) was used as in FIG. 15, and polycarbonate was used as a resin to be impregnated into the carbon fiber under pressure. FIG. 16 (a) shows the correlation between the applied pressure (final ultimate pressure) when the molding temperature is maintained at 270 ° C. and the thickness of the obtained resin prepreg (polycarbonate / carbon fiber prepreg). 3 shows the correlation between the molding temperature and the thickness of the obtained resin prepreg while changing the applied pressure from 3 MPa to 7 MPa. The carbon fiber used was a unidirectional carbon fiber substrate T800SC (SARTEX, 24K).
From FIG. 16 (a), when the molding temperature is constant, the thickness tends to decrease as the applied pressure increases. On the other hand, from (b), when the pressing force is constant, the thickness tends to decrease as the molding temperature rises.

  In order to clarify the effect of the present invention from another point of view, as a comparative product, the same carbon fiber sheet was not subjected to a stitching process but only subjected to a fiber opening treatment or the like with acetone, and a prepreg was molded in exactly the same manner. FIG. 17 shows the carbon fiber sheet that has been subjected to the above-described opening process using acetone. FIG. 18 is a polycarbonate / carbon fiber prepreg manufactured using a carbon fiber sheet that has been subjected only to the fiber opening treatment and the like. In the polycarbonate / carbon fiber prepreg using the continuous reinforcing fiber sheet that has been subjected to the stitching treatment and the fiber opening treatment shown in FIG. 5-7, it can be observed that both surfaces are sufficiently impregnated with the resin. In the polycarbonate / carbon fiber prepreg shown in a), many unimpregnated regions of the resin can be observed on one side, and it can be seen that poor impregnation occurs. In addition, the enlarged photograph shown in FIG. 18B clearly shows that the unimpregnated carbon fiber is popping out. The reason for this difference in resin impregnation results is that in the case of continuous reinforcing fiber sheets that have been subjected to stitching treatment and fiber opening treatment, the resin impregnation is promoted by securing the inflow path of the thermoplastic resin by the stitching treatment. Yes, this implementation result is an example that clearly shows the effect of the present invention.

  Next, the obtained polycarbonate / carbon fiber prepreg is cut into a size of 200 × 200 mm in a mold for forming a laminate, and this is angularly oriented at 0/90/90/0/0/90/90/0. Laminated. At the same time, one polycarbonate sheet of the same size as the polycarbonate / carbon fiber prepreg was laminated on the surface. The prepreg and the mold on which the polycarbonate sheet was placed were placed in a hot press set at a hot platen temperature of 310 ° C., which was the same as that for molding the polycarbonate / carbon fiber prepreg. Preheating was performed at a temperature of 310 ° C. for 10 minutes, and the pressure increase rate was increased to 4 MPa by 1 MPa at intervals of 1 min. Next, the pressure was increased by 2 MPa at intervals of 1 min. After increasing the pressure to 10 MPa, the hot press hot platen was switched off and the air was naturally cooled to 190 ° C. while maintaining the pressure value. When the temperature dropped to 190 ° C., it was further cooled to 110 ° C. using the water-cooling function of the hot press and depressurized for demolding. By the above molding method, a polycarbonate / carbon fiber orthotropic composite laminate (average thickness 3.5 mm) was obtained. FIG. 19 shows a photograph of the appearance of the laminate. No significant disturbance in fiber bundle orientation or poor impregnation is observed. FIGS. 20 (a) to 20 (d) show photographs taken with an optical microscope of cut specimens made by cutting the molded laminate and polishing the cut surfaces. FIG. 20 (a) shows a cross-sectional view of a laminate including different fiber orientations, but no voids or the like are seen, and it can be seen that resin impregnation is performed reliably. 20 (b) to 20 (c) are enlarged views of the cross sections of the respective layers, and it can be seen that the resin flows and adheres around the respective fibers. FIG. 20 (d) is a cross-sectional photograph of the periphery of the suture, and it can be seen that there are no voids or the like around the suture and the resin is sufficiently impregnated. From the above, since the impregnation state of the resin is good and the fiber orientation is not particularly disturbed, it is considered that the present composite material can be used satisfactorily as an industrial material.

  The main equipment used to obtain this polycarbonate / carbon fiber reinforced composite laminate is a commercial industrial sewing machine and hot press, including the production of prepregs. It has been proved that it can be obtained. In addition, prepreg manufacturing time can be controlled by optimizing the stitching method and stepwise pressurization method, and a large area prepreg can be manufactured at once with a large hot press. I can do it. From this, it is considered that the production amount of the composite material laminate per unit time can be easily increased.

  However, it was confirmed that a crack in the layer partially occurred inside the laminated board of this example. This is considered to be because the annealing treatment for removing the thermal residual stress of the thermoplastic resin was not carried out in this embodiment for the cooling treatment of the polycarbonate resin molded product. Therefore, it is particularly added that the method of obtaining a good molded product by optimizing the annealing treatment method is also one of the present inventions.

  In Example 1 above, polycarbonate / carbon fiber prepreg, which is a thermoplastic resin prepreg, is produced by the production method of the present invention using polycarbonate sheet 4 which is a thermoplastic resin as a matrix resin to be impregnated between the fibers of carbon fiber sheet 1. An example of producing a thermosetting resin as a matrix resin, such as an epoxy resin, a phenol resin, an unsaturated polyester resin, a urethane resin, a urethane acrylate resin, a vinyl ester resin, a cyanate ester resin, a phenoxy resin, It is also possible to produce a thermosetting resin prepreg by the production method of the present invention using an alkyd resin, a maleimide resin, or a thermosetting resin in which these are mixed. Examples of a method for producing an ultraviolet curable resin laminated composite structure using an ultraviolet curable resin as a matrix resin will be described below. The ultraviolet curable resin can be impregnated with resin at room temperature, and the resin is cured by ultraviolet irradiation. Therefore, similar to the method for producing the thermoplastic resin prepreg shown in Example 1, it is possible to produce a composite material structure quickly with extremely simple equipment.

  As a method for producing a laminated composite material structure using an ultraviolet curable resin as a matrix, it is not necessary to heat the resin during resin impregnation. That is, the resin is pressure-impregnated at room temperature using a hand roller or a press machine, for example, by applying a gel-like ultraviolet curable resin to a continuous reinforcing fiber sheet that has been treated such as sewing and opening. At this time, the impregnating property is improved by maintaining the fiber orientation of the suture and also the region of the suture as a resin inflow path even for an ultraviolet curable resin having a high viscosity. Further, by opening the fiber bundle, the resin flows into the periphery of the fiber bundle to improve the adhesiveness. By selecting a resin that cures in response to ultraviolet rays of a certain wavelength, there is no restriction on the working environment. The reinforced fiber sheet is dry, and the management cost can be kept lower than that of the prepreg by storing the resin in a tube or the like. In this way, a wet (resin is uncured) UV curable resin prepreg is produced. After laminating a plurality of the prepregs, pressurization is performed at room temperature using a hand roller or a press, and air between layers is expelled and adhered. Finally, by irradiating ultraviolet rays to cure the resin, an ultraviolet curable resin laminated composite structure can be manufactured very quickly and at low cost.

The present invention relates to a method for producing a resin prepreg using a thermoplastic resin or a thermosetting resin and a continuous reinforcing fiber sheet. More specifically, the present invention relates to a method for producing a resin prepreg that can be molded at low cost without using special equipment by a continuous reinforcing fiber sheet subjected to a stitching process, a fiber opening process, and the like.
The thermoplastic resin prepreg or the composite material formed by the thermosetting resin prepreg obtained in the present invention can be used as an automobile material, a building material, an aircraft material, an electrical material, or the like.
Furthermore, specific industrial applicability is described. In particular, in the case of the polycarbonate carbon fiber reinforced composite material obtained in the examples of the present invention, the polycarbonate resin as one of the base materials is extremely excellent in impact resistance, lightweight, excellent in weather resistance and dimensional accuracy, and It is a low-cost engineering plastic that can be recycled. For this reason, it can be applied to automobile bumpers. Furthermore, depending on the type of reinforcing fiber such as carbon fiber for composite materials used in aircraft, the rigidity can be increased to the level of aluminum, and it can be applied as a structural member that can recycle transportation equipment including automobiles. . In addition, since the resin is excellent in impact resistance, it can be applied to a debris bumper of a space structure, an anti-shock structure such as a bulletproof shield, an outer wall such as a shelter, and a structural material such as a safe.

It is a photograph which shows the carbon fiber sheet to which the suturing process concerning this invention was given. It is a photograph which shows the continuous reinforcement fiber sheet in which the stitching process and the fiber opening process, etc. according to the present invention were performed. It is explanatory drawing which shows the continuous reinforcement fiber sheet | seat in which the sewing process and opening process, etc. which concern on this invention were given. It is explanatory drawing which shows an example of the equipment which enforces the manufacturing method of the polycarbonate * carbon fiber prepreg which is an Example of this invention. It is a photograph which shows the polycarbonate carbon fiber prepreg obtained with the manufacturing method of the resin prepreg of this invention. It is an enlarged photograph around the suture thread of the polycarbonate carbon fiber prepreg obtained in the example of the present invention. It is a microscope picture which shows the suture periphery of a polycarbonate carbon fiber prepreg obtained with the manufacturing method of this invention, and a suture periphery periphery. It is explanatory drawing which shows the pressurization process which pressurizes and impregnates a continuous reinforcement fiber sheet with resin. It is a graph which shows the result of the static tensile test of the polycarbonate carbon fiber prepreg concerning the present invention. It is a graph which shows the result of the compression test of the polycarbonate carbon fiber prepreg which concerns on this invention. It is a graph which shows the result of the bending test of the polycarbonate carbon fiber prepreg which concerns on this invention. It is a photograph which shows the observation result after the falling weight impact test of the polycarbonate carbon fiber prepreg according to the present invention. It is a photograph which shows the deformation | transformation state after a falling weight impact test of 62.5J about the epoxy carbon fiber prepreg which impregnated the said continuous reinforcement fiber sheet with the epoxy resin. It is a graph which shows the load and energy log | history at the time of each (energy conversion: 12J, 36J, 70J) impact test. It is a photograph which shows the internal observation result of the polycarbonate carbon fiber prepreg obtained by applying the manufacturing method of the resin prepreg of this invention to high strength and highly elastic carbon fiber. It is a graph which shows the influence which pressurization force and molding temperature have on the thickness of a resin prepreg. It is a photograph which shows the carbon fiber sheet to which only the fiber-opening process was performed in order to compare a polycarbonate and carbon fiber prepreg obtained by the Example of this invention, and a shaping | molding state. It is a photograph which shows what produced the prepreg by the same resin impregnation method with the carbon fiber sheet and polycarbonate sheet of only the fiber opening process (a lot of unimpregnated parts generate | occur | produced). It is an external appearance photograph which shows the polycarbonate and carbon fiber orthotropic composite-material laminated board manufactured by laminating | stacking the polycarbonate and carbon fiber prepreg obtained in the Example of this invention, and heating and pressurizing. It is a microscope picture which shows the cross-sectional part of the polycarbonate carbon fiber orthotropic composite material laminate obtained in this example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Carbon fiber sheet 2 Heat resistant thread 3 Carbon fiber sheet processed by stitching and fiber opening 4 Polycarbonate sheet 5 Spacer 6 Upper heating / pressurizing plate 7 Lower heating / pressurizing plate 10 Continuous reinforcing fiber sheet

Claims (29)

A method for producing a resin prepreg comprising pressurizing and impregnating a matrix resin between fibers of a fiber sheet, wherein the fiber sheet is a sheet formed by aligning reinforcing fibers in one direction. On the other hand, a continuous reinforcing fiber sheet is obtained by performing a suturing process in which a sewing thread is sewn in a direction crossing the fiber orientation, and then performing a fiber opening process for removing the drug applied to the fiber and opening the fiber bundle. A method for producing a resin prepreg characterized by the above.   The resin prepreg according to claim 1, wherein in the fiber opening treatment, a coupling agent capable of obtaining an interface control effect is newly attached to the fiber surface in order to improve the adhesion between the fiber sheet and the matrix resin. Method. It said fibers of the reinforcing fiber sheets, manufacturing method of the resin prepreg according to claim 1 or 2 is selected from carbon fibers, glass fibers, aramid fibers, or ceramic fibers. The continuous reinforcing fiber sheet is a continuous fiber sheet for resin reinforcement that is combined with a thermoplastic resin, a thermosetting resin, or a mixed resin of a thermoplastic resin and a thermosetting resin and used as a reinforcing substrate. The manufacturing method of the resin prepreg of any one of 1-3 . The continuous reinforcing fiber sheet, a resin according to any one of claims 1 to 4 wherein the suture processed by sutures having high heat resistance than the melting point of the matrix resin is a continuous fiber sheet for reinforcing resins subjected A method for producing a prepreg. The sutures, Nomex (registered trademark), Conex ®, Pyro Mex ®, Las Tex (registered trademark), Zylon (registered trademark), or Vectran high strength and high selected from (R) The method for producing a resin prepreg according to claim 5, wherein the resin prepreg is a rigid heat-resistant yarn. The continuous reinforcing fiber sheet sews the heat-resistant yarn in a direction crossing the fiber orientation direction by a stitch length, a stitching length, and a stitching interval determined according to the viscosity of the matrix resin and the impregnation time of the resin. method for producing a resin prepreg according to any one of sewing processes from claim 1 which is a continuous fiber sheet for reinforcing resins subjected 6. The continuous reinforcing fiber sheet is a continuous fiber sheet for resin reinforcement that maintains handling properties even after removing a sizing agent that prevents the fibers from being loosened by performing the stitching process. method for producing a resin prepreg according to any one of claims. When the continuous reinforcing fiber sheet is subjected to the suturing treatment, when the matrix resin is pressure-impregnated, the fiber orientation of the opened fiber sheet is suppressed, and the stitched portion becomes a resin inflow path. method for producing a resin prepreg according to any one of the resin reinforced improve the impregnation of the resin continuous fiber sheet in which claims 1 to 8 by. The continuous reinforcing fiber sheet has an interface control on the fiber surface in order to improve the adhesion and wettability according to the matrix resin to be impregnated in the fiber opening treatment after the stitching treatment is performed. the method of manufacturing a resin prepreg according to any one of claims 1 to 9 coupling agent effect is obtained is a resin reinforcing continuous fiber sheet added. 11. The resin according to claim 10, wherein as the coupling agent, any coupling agent selected from silane, titanate, aluminate, and zirconate is added to the fiber surface according to the resin to be impregnated. A method for producing a prepreg. 12. The matrix resin is a thermoplastic resin sheet , the thermoplastic resin sheet is disposed on one or both sides of the continuous reinforcing fiber sheet, the resin sheet is heated and melted, and pressure impregnated between fibers. The manufacturing method of the resin prepreg of any one of these.   When the thermoplastic resin sheet is disposed on one or both sides of the continuous reinforcing fiber sheet and the resin sheet is heated and melted and pressure impregnated between the fibers, the pressure is increased by increasing the viscosity of the resin and The method for producing a resin prepreg according to claim 12, wherein the method is performed stepwise at a timing corresponding to the conditions of the stitching process and the fiber opening process of the reinforcing fiber sheet.   Claims: The thermoplastic resin sheet is disposed on one or both sides of the continuous reinforcing fiber sheet, the resin sheet is heated and melted and subjected to pressure impregnation, and then the formed product is annealed by an optimum method. Item 14. A method for producing a resin prepreg according to Item 12 or 13. The thermoplastic resin is any one of vinyl chloride, acrylonitrile butadiene styrene resin (ABS), polyethylene, polypropylene, polyamide, polyacetal, polycarbonate, polybutylene terephthalate, polyimide, polyphenylene sulfide, polyethersulfone, or polyetheretherketone. method for producing a resin prepreg according to any one of certain claims 12 14. The matrix resin is a thermosetting resin , and the thermosetting resin is press-fitted into the continuous reinforcing fiber sheet subjected to the stitching process and the fiber opening process to impregnate and cure between the fibers. method for producing a resin prepreg according to any one of 1 to 11. The matrix resin is a thermosetting resin , and the thermosetting resin is vacuum-pressed into the continuous reinforcing fiber sheet subjected to the stitching process and the fiber opening process to impregnate and cure between the fibers. Item 17. A method for producing a resin prepreg according to Item 16 . The thermosetting resin may be epoxy resin, phenol resin, unsaturated polyester resin, urethane resin, urethane acrylate resin, vinyl ester resin, cyanate ester resin, phenoxy resin, alkyd resin, maleimide resin, or a mixture of these. The method for producing a resin prepreg according to claim 16 or 17 , which is any one of curable resins. When the matrix resin is an ultraviolet curable resin and the continuous reinforcing fiber sheet is impregnated with the ultraviolet curable resin as a matrix resin by applying the stitching treatment, the fiber orientation of the opened fiber sheet is disturbed. The method for producing a resin prepreg according to any one of claims 1 to 11, wherein the resin prepreg is a continuous fiber sheet for reinforcing an ultraviolet curable resin that is suppressed and has a stitched portion as a resin inflow path to improve the impregnation property of the resin. A fiber sheet that is formed by aligning reinforcing fibers in one direction to form a sheet, and that opens the fiber bundle by removing the agent applied to the fiber and stitching the sewing thread in a direction that intersects the fiber orientation. A continuous reinforcing fiber sheet is obtained by performing the treatment, and the continuous reinforcing fiber sheet is stitched in a direction crossing the fiber orientation with a thread having heat resistance than the matrix resin of the prepreg by the stitching process. Fiber sheet for resin prepreg. Suture portion into which the yarn passes through between the fibers, by a flowing path of the matrix resin, resin prepreg fiber sheet according to claim 20 for improving the impregnation of the matrix resin. The yarn is high strength and high selected from Nomex (registered trademark), Conex (registered trademark), Pyromex (registered trademark), Lastex (registered trademark), Zylon (registered trademark), or Vectran (registered trademark). The fiber sheet for resin prepreg according to claim 20 or 21 , which is rigid. The fiber sheet, carbon fiber, fiber sheet resin prepreg according to any one of claims 20 to 22 glass fibers, a reinforcing fiber selected from among aramid fibers, or ceramic fibers. Said fiber sheet, a thermoplastic resin, thermosetting resin, according to claim 20 for use as an ultraviolet curable resin or composite is reinforced base of a resin selected from a resin mixture of a thermoplastic resin and a thermosetting resin, resin prepreg fiber sheet according to any one of to 23. To maintain the handling properties even after the removal of the sizing agent to prevent Keru loose fibers, according to any one of claims 20 to 24 which is sewn in a direction intersecting the orientation of the fibers in the yarn Fiber prepreg fiber sheet. A resin prepreg obtained by impregnating a fiber resin sheet for resin prepreg according to any one of claims 21 to 25 with a matrix resin. 27. The resin prepreg according to claim 26, wherein the matrix resin is any one of a thermoplastic resin, a thermosetting resin, and an ultraviolet curable resin. A composite material obtained by laminating a plurality of the resin prepregs according to claim 26 or 27 and pressurizing the composite material. 29. The composite material according to claim 28, wherein the lamination of the resin prepreg is formed by laminating the resin prepreg by alternately changing the angular orientation.