JP2006111737A - Method for producing fiber-reinforced composite material and fiber-reinforced composite material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a fiber-reinforced composite material having a smooth surface with excellent heat resistance and solvent resistance in a short time. <P>SOLUTION: The method for producing the fiber-reinforced composite material comprises pouring the following constituent element [C] into a mold in which the following constituent elements [A] and [B] are set to impregnate the constituent element [A] with the constituent element [C], curing the product and releasing the mold from the molded product: [A] a reinforcing fiber base material; [B] a thermosetting resin sheet and [C] a liquid thermosetting resin composition. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is a molding method in which a liquid thermosetting resin is injected into a mold in which a reinforcing fiber base is set, and the reinforcing fiber base is impregnated and cured, and then the molded product of the fiber reinforced composite material is demolded. The present invention relates to a production method for obtaining in a short time a fiber-reinforced composite material having a smooth surface such that a mapping is clearly projected in a resin transfer molding method (hereinafter referred to as RTM method).

  Fiber reinforced composites consisting of reinforcing fibers such as glass fibers, carbon fibers, aramid fibers, alumina fibers, and boron fibers, and cured products of thermosetting resins such as unsaturated polyester resins, vinyl ester resins, epoxy resins, and phenol resins Since the material is lightweight and has excellent mechanical properties such as strength and elastic modulus, it is used in many applications such as aircraft members, automobile members, railway vehicle members, ship members, and sports equipment.

  As a method for producing a fiber reinforced composite material, a hand lay-up method, a filament winding method, a pultrusion method, an RTM method, a method using a prepreg which is a sheet-like intermediate base material in which a reinforced fiber is impregnated with a matrix resin are known. Yes. Among these manufacturing methods, the RTM method has attracted attention because it has an advantage that a large member having a complicated shape can be formed in a short time.

  However, in the RTM method, in the obtained fiber reinforced composite material, surface unevenness according to the unevenness of the reinforcing fiber base to be used occurs, so that there is a problem that a smooth surface where the mapping is clearly projected cannot be obtained. there were. For this reason, when applying a molded product obtained by the RTM method to an outer plate member that is often seen directly by the user and that requires design properties, in particular, an automobile outer plate member such as a hood, a roof, or a trunk lid, Since the process of polishing the surface of the fiber reinforced composite material and reducing the surface roughness is newly required, the time required for the entire process from molding to finishing is not substantially shortened, and the molding process is an advantage of the RTM method. The effect of shortening the time was not obtained.

  The following techniques are known as methods for obtaining a fiber-reinforced composite material having a smooth surface by the RTM method.

  As a first method, there is a method using a gel coat. In this method, a liquid resin composition (gel coat) composed of an unsaturated polyester resin, a vinyl ester resin or the like is applied and cured to a predetermined thickness on a mold to form a resin layer (gel coat layer). Thereafter, a fiber reinforced base material is laminated and the RTM method is performed (for example, refer to Patent Documents 1 and 2). In this method, by forming a gel coat layer on the surface of the fiber reinforced composite material, surface irregularities are reduced, and a relatively smooth surface can be obtained. However, since this method usually requires several tens of minutes to several hours to apply and cure the gel coat, the effect of shortening the molding time is little compared to the method of polishing the surface of the fiber-reinforced composite material and reducing the surface roughness. It was not.

Another method is to use a sheet of thermoplastic resin. In this method, a surface layer having a shape that can be brought into close contact with the mold surface is prepared in advance using a thermoplastic resin sheet, and after setting the surface layer material in the mold, the reinforcing fiber base material is laminated and the RTM method is performed. (For example, refer to Patent Documents 3 and 4). In this method, by forming a resin layer made of a thermoplastic resin on the surface of the fiber reinforced composite material, surface irregularities are reduced, and a relatively smooth surface can be obtained. In addition, it can be molded in a short time. However, in this method, since a thermoplastic resin sheet is used, there is another problem that it is difficult to select a material having both heat resistance and solvent resistance.
JP-A-8-207149, page 2 JP 2003-48263 A, page 2 JP 7-214677 A, page 3 JP 2001-288230 JP, page 2

  An object of the present invention is to provide a production method for obtaining a fiber-reinforced composite material having a smooth surface and excellent heat resistance and solvent resistance in a short time.

In order to solve the above problems, the present invention has the following configuration. That is, the component [C] is injected into a mold in which the following components [A] and [B] are set, impregnated and cured in the component [A], and then the molded product is demolded. An object of the present invention is to provide a method for producing a fiber-reinforced composite material.
[A] Reinforcing fiber substrate [B] Thermosetting resin sheet [C] Liquid thermosetting resin

  By using the RTM method in which a thermosetting resin sheet is placed on the surface of a reinforced fiber composite material, a reinforced fiber composite material having a smooth surface can be obtained in a short time, and efficient parts such as automotive outer panels are required. It can be manufactured well. Moreover, since a thermosetting resin sheet is used, a surface excellent in heat resistance and solvent resistance can be obtained.

  The inventors focused on the fact that the cured product of the thermosetting resin is excellent in heat resistance and solvent resistance, and formed a resin layer composed of the cured product of the thermosetting resin on the surface of the fiber reinforced composite material, and smoothed the surface. Furthermore, it was considered to obtain a surface excellent in heat resistance and solvent resistance. Furthermore, in order to realize the molding in a short time, the inventors have conceived a method of setting a sheet of thermosetting resin in the RTM method. In this method, since the thermosetting resin can be set in the mold in a short time, the molding time can be greatly reduced as compared with the method of polishing the surface of the fiber reinforced composite material and the method of using gel coat. Moreover, by using a sheet of thermosetting resin, setting to a mold having a complicated shape is facilitated.

  As the reinforcing fiber applied to the present invention, glass fiber, carbon fiber, aramid fiber, alumina fiber, boron fiber and the like are used. Among these, carbon fibers are preferably used because they have excellent characteristics of high strength and high elastic modulus while being lightweight.

  As the reinforcing fiber base material in the present invention, woven fabrics, blades, mats, etc. of reinforcing fibers are used, and these are laminated, shaped, and fixed in form by means such as adhesives and stitches to form a preform. Those are also preferably used.

  The thermosetting resin sheet in this invention is used in order to form the resin layer which consists of hardened | cured material on the surface of a fiber reinforced composite material, and to obtain a smooth surface.

  As the thermosetting resin in the thermosetting resin sheet applied to the present invention, unsaturated polyester resin, vinyl ester resin, epoxy resin, phenol resin, and the like are used. Among them, an epoxy resin is preferably used because the curing shrinkage is small and the molded product is less likely to warp. Moreover, when using an epoxy resin in combination with a carbon fiber, there also exists an advantage that adhesiveness with a carbon fiber is excellent.

  As the epoxy resin in the thermosetting resin sheet applied to the present invention, an epoxy resin having an average of 2 or more epoxy groups per molecule is preferably used. Specific examples include bisphenol A type epoxy resin, bisphenol F type epoxy resin, novolac type epoxy resin, cresol novolac type epoxy resin, aminophenol type epoxy resin, triphenylglycidyl ether methane, tetraglycidyl diaminodiphenylmethane, tetraglycidyl metaxylenediamine. And tetraphenylglycidyl ether ethane. Especially, since the hardened | cured material which is excellent in the balance of heat resistance and toughness is obtained, a bisphenol A type epoxy resin and a bisphenol F type epoxy resin are used preferably.

  Curing agents to be combined with the epoxy resin in the thermosetting resin sheet applied to the present invention include addition curing agents such as polyamines, hydrazides, dicyandiamides, acid anhydrides and phenols, anionic polymerization curing agents such as tertiary amines, 3 A cationic polymerization curing agent such as boron fluoride is used. Among these, dicyandiamide is preferably used because it has appropriate storage stability and curability.

  When the thermosetting resin sheet applied to the present invention contains an epoxy resin, a curing catalyst can also be used. As the curing catalyst, an imidazole-based curing catalyst or a urea-based curing catalyst is used. Especially, since it has moderate storage stability and curability, 3-phenyl-1,1-dimethylurea, 3- (3,4-dichlorophenyl) -1,1-dimethylurea (DCMU), 3- (3 Urea-based curing catalysts such as chloro 4-methylphenyl) -1,1-dimethylurea and 2,4-toluenebis (dimethylurea) are preferably used.

  In the thermosetting resin sheet applied to the present invention, a thermoplastic resin can be blended because it has an appropriate tack and can be easily set in a mold. As the thermoplastic resin, polyethylene oxide, polymethyl methacrylate, polyvinyl formal, polysulfone, polyethersulfone, polyetherimide and the like are preferably used.

  Moreover, in the thermosetting resin sheet applied to this invention, since it has moderate thixotropy and can suppress an excessive flow, an inorganic filler can be mix | blended. As the inorganic filler, calcium carbonate, clay, talc, silica, wollastonite and the like are preferably used.

  In the thermosetting resin sheet applied to the present invention, since the sheet can have an appropriate strength, woven fabrics such as glass fibers, polyesters, and polyamides, knitted fabrics, and nonwoven fabrics can be used as the carrier. Specifically, a woven fabric, a knitted fabric, or a nonwoven fabric that is completely impregnated with a thermosetting resin or partially impregnated into a sheet shape can be used.

  In the thermosetting resin sheet applied to the present invention, the thickness is preferably in the range of 50 to 800 μm, and if it is thinner than 50 μm, a smooth surface may not be obtained. In addition, if it is thicker than 800 μm, the feature of the fiber-reinforced composite material that it is lightweight may be impaired.

  The liquid thermosetting resin applied to the present invention is used as a matrix resin for a fiber-reinforced composite material.

  As the liquid thermosetting resin applied to the present invention, unsaturated polyester resin, vinyl ester resin, epoxy resin, phenol resin, etc. are used, but because of excellent adhesion with the above-mentioned thermosetting resin sheet, It is preferable to use the same type of thermosetting resin as the thermosetting resin sheet. Alternatively, it is preferable to select a combination that can form a covalent bond. Of these, an epoxy resin having excellent adhesion to carbon fibers is preferably used.

  As the epoxy resin in the liquid thermosetting resin applied to the present invention, it is preferable to use one having an average of two or more epoxy groups per molecule. Specific examples include bisphenol A type epoxy resin, bisphenol F type epoxy resin, novolac type epoxy resin, cresol novolac type epoxy resin, aminophenol type epoxy resin, triphenylglycidyl ether methane, tetraglycidyl diaminodiphenylmethane, tetraglycidyl metaxylenediamine. And tetraphenylglycidyl ether ethane. Especially, since the hardened | cured material which is excellent in the balance of heat resistance and toughness is obtained, a bisphenol A type epoxy resin and a bisphenol F type epoxy resin are used preferably.

  Curing agents combined with epoxy resins in the liquid thermosetting resin sheet applied to the present invention include addition curing agents such as polyamines, hydrazides, dicyandiamides, acid anhydrides and phenols, and anionic polymerization curing agents such as tertiary amines. A cationic polymerization type curing agent such as boron trifluoride is used.

  As a mold applied to the present invention, a sealed mold in which a cavity is surrounded only by a rigid material or an open mold in which a cavity is surrounded by a rigid material and a bagging film can be used.

  As the material of the mold applied to the present invention, carbon steel, alloy steel, cast iron, aluminum, aluminum alloy, nickel alloy and other metals, FRP (Fiber Reinforced Plastic), wood and the like can be used. Moreover, as a material for the bagging film used in the open type, polyamide, polyester, silicone, or the like can be used.

  In the present invention, as a first method for setting the reinforcing fiber base of the component [A] and the thermosetting resin sheet of the component [B] in the mold, after setting the thermosetting resin sheet in the mold, The method of laminating a reinforcing fiber substrate is mentioned. This method has an advantage that the thermosetting resin sheet can be easily set in a mold having a complicated curved surface.

  In the present invention, as another method of setting the reinforcing fiber base material of the component [A] and the thermosetting resin sheet of the component element [B] in the mold, the thermosetting resin sheet is provided on at least one side of the reinforcing fiber base material. There is a method in which after preparing a pre-laminated body having laminated layers, the pre-laminated body is set in a mold. This method has an advantage that the working time on the mold can be shortened as compared with the method of laminating the reinforcing fiber base after setting the thermosetting resin sheet in the mold. In the RTM method, the production amount of the fiber reinforced composite material is determined by an amount obtained by multiplying the “production amount per mold” by the “number of molds”. Therefore, by shortening the working time on the mold, “1 The production amount per mold ”can be increased, and as a result, the production amount of the fiber-reinforced composite material can be increased.

  In the present invention, an adhesive material such as a tack fire can be used in order to fix the reinforcing fiber bases and improve the handleability. Further, in order to fix the reinforcing fiber base and the thermochemically-resin film and improve the handleability, a thermosetting resin sheet having a tack or an adhesive material such as a tack fire can be used.

  In the present invention, the reinforcing fiber base material and the thermosetting resin sheet are set in the mold, and then the mold is closed. When using a sealed mold, clamp the upper mold and lower mold with bolts, clamps, etc., or attach the upper mold and lower mold to the press and clamp the upper mold and lower mold with the press pressure. Close the mold by the method. In the case of using an open mold, the mold made of a rigid material and the bagging film are closed by a method using a sealing material or the like.

  In the present invention, after the mold is closed, the liquid thermosetting resin of the component [C] is injected into the mold.

  In the present invention, the time for starting the injection of the liquid thermosetting resin is within 30 minutes from the time when the thermosetting resin sheet is set in the mold in order to realize molding in a short time. Is preferred. In the present invention, the time for starting the injection refers to the time for the liquid thermosetting resin to start flowing into the mold.

  Further, in the present invention, in order to obtain a fiber-reinforced composite material having a particularly smooth surface, after the thermosetting resin sheet is set in a mold, the glass transition temperature (Tg) of the thermosetting resin sheet is the following condition ( It is preferable to start injection of the liquid thermosetting resin into the mold in a state satisfying 5). If the Tg of the thermosetting resin sheet satisfies the following condition (5), the thermosetting resin sheet has sufficient rigidity, and surface irregularities are generated due to curing shrinkage of the liquid thermosetting resin. It can be suppressed more effectively.

Tg ≧ Tm (MAX) -30 (5)
Tg: Glass transition temperature (° C.) of component [B]
Tm (MAX): Maximum mold temperature (° C)
Here, whether the Tg of the thermosetting resin sheet satisfies the above condition (5) is determined by the following method. A thermosetting resin sheet is set on the mold so as to have a thickness of about 2 mm. While controlling the mold temperature according to the molding conditions, the thermosetting resin sheet is sampled every arbitrary time, and Tg is measured. At this time, a thermocouple is attached near the center of the lower mold, the mold temperature is measured, and the maximum mold temperature (Tm (MAX)) is obtained. The time when the thermosetting resin sheet is set in the mold is set to 0 (minutes), and the measured Tg is plotted against the sampling time to create a time-Tg curve, and Tg satisfies the above condition (5). The minimum time t (minutes) required for Thereafter, when the same molding conditions are used, it is determined that Tg satisfies the above condition (5) if t (minutes) or more has elapsed since the thermosetting resin sheet was set in the mold.

  Here, Tg of a thermosetting resin sheet is measured based on SACMA SRM 18R-94 using a viscoelasticity measuring apparatus. However, the measurement is performed in the Rectangular Torsion mode, the measurement frequency is 1 Hz, and the temperature increase rate is 5 ° C./min. In the obtained temperature-storage modulus curve, the intersection of the tangent in the glass region and the tangent in the transition region from the glass region to the rubber region is obtained, and the temperature of this intersection is defined as the glass transition temperature.

  In the present invention, the mold temperature can be maintained at a constant temperature, or a combination of temperature increase, temperature decrease, and constant temperature can be combined. In particular, the temperature raising and lowering steps of the mold can be omitted, and molding in a short time can be realized, so that the entire temperature is maintained at Tm ± 10 ° C. with respect to the specific temperature Tm included in the range of 60 to 180 ° C. It is preferable to do. When Tm is lower than 60 ° C., the heat resistance of the cured product obtained by curing the thermosetting resin sheet and the liquid thermosetting resin may be insufficient. On the other hand, if Tm is higher than 180 ° C., the viscosity of the liquid thermosetting resin increases rapidly, and an unimpregnated part may be formed in the fiber-reinforced composite material.

In the present invention, the time required for the injection and the time from the start of injection to the start of demolding can sufficiently secure the time required for injection, and a relatively large fiber-reinforced composite material can be formed. Therefore, the following conditions (6) to (8) are satisfied in a state where the mold temperature is maintained at Tm ± 10 ° C. with respect to the specific temperature Tm included in the range of 60 to 180 ° C. It is preferable that ti ≧ 10 (6)
tm ≦ 60 (7)
1 <tm / ti ≦ 6.0 (8)
ti: Time from the start of injection to the end of injection (minutes)
tm: Time (minutes) from the start of injection to the start of demolding of the molded product.

  Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. The main data of Examples and Comparative Examples are summarized in Table 1.

The materials used in Examples and Comparative Examples are as follows.
1. Carbon fiber fabric The reinforcing fiber base material of the constituent element [A] suitable for the present invention is carbon fiber fabric CO6343B (product number, “Torayca” T300-3K used, 198 g / m ² per unit weight, manufactured by Toray Industries, Inc.) Was used.
2. Thermosetting resin sheet “Epicoat” (registered trademark) 828 (bisphenol A type epoxy resin, Japan Epoxy Resin Co., Ltd.) 100 parts by weight, “Admafine” (registered trademark) SO-C5 (spherical silica particles, granules) Diameter 1.3-2.0 μm, Admattex Co., Ltd.) 95 parts by weight, Dicy7 (Dicyandiamide, curing agent, Japan Epoxy Resin Co., Ltd.) 4.2 parts by weight, DCMU-99 (Part No. 3- ( 3,4-dichlorophenyl) -1,1-dimethylurea, curing catalyst, manufactured by Hodogaya Chemical Co., Ltd.), 3 parts by weight, “Vinylec K” (registered trademark) (polyvinyl formal, thermoplastic resin, Chisso Corporation) (Product) 10 parts by weight was added to MEK and mixed to prepare a resin varnish. After this is well dispersed using a three-roll (EXAKT80, manufactured by EXAKT), it is thick on the release paper using a small applicator (model number 350FA B type, film thickness 600 μm, manufactured by Coating Tester Co., Ltd.). Filming was performed on a 600 μm sheet. Next, the sheet was left to stand for 7 hours under reduced pressure in a vacuum dryer set at 30 ° C. for 30 minutes in a hot air dryer at 55 ° C. and dried for 7 hours, and then the sheet was peeled off from the release paper. A thermosetting resin sheet was prepared. The thickness of the thermoplastic resin sheet after drying was 350 μm.
3. Liquid thermosetting resin “Epicoat” (registered trademark) 828 (bisphenol A type epoxy resin, manufactured by Japan Epoxy Resins Co., Ltd.) is added to “Cureazole” (registered trademark) 2E4MZ (2-ethyl-4-methylimidazole). 3 parts by weight of an anionic polymerization type curing agent, manufactured by Shikoku Chemicals Co., Ltd.) was added and stirred well to prepare a liquid thermosetting resin.
4). Gel coat NR-AC0001P (product number, acrylic resin gel coat, manufactured by Toago Material Technology Co., Ltd.) was used as the gel coat of the comparative example.

Next, measurement methods in Examples and Comparative Examples are shown below.
1. Surface Roughness Measurement A fiber reinforced composite material obtained by molding was cut into a size of 5 cm in length and 2 cm in width using a diamond cutter to prepare a sample. A surface roughness profile was obtained using a contact-type surface roughness meter, Surfcorder SE3400 (manufactured by Kosaka Laboratory Ltd.) at any five locations of the sample. At this time, the direction of measurement was made different. The surface unevenness profile was enlarged and output so that the height of the unevenness could be recognized sufficiently. Next, as shown in FIG. 1, the height R from the concave portion to the convex portion of the unevenness was measured at three places for each profile, a total of 15 places, and an average value was calculated.
2. Measurement of glass transition temperature (Tg) of thermosetting resin sheet A thermosetting resin sheet was set on a mold so as to have a thickness of about 2 mm, and cured under predetermined conditions to prepare a sample. Next, Tg was measured based on SACMA SRM 18R-94 using a viscoelasticity measuring device. However, the measurement was performed in the Rectangular Torsion mode, the measurement frequency was 1 Hz, and the temperature elevation rate was 5 ° C./min. In the obtained temperature-storage modulus curve, the intersection of the tangent in the glass region and the tangent in the transition region from the glass region to the rubber region was determined, and the temperature at this intersection was taken as the glass transition temperature.
3. Chemical resistance test of fiber reinforced composite material After dropping a few drops of methyl ethyl ketone, ethanol, toluene, and methylene chloride on the surface of the fiber reinforced composite material using a pipette, wipe with a cloth, before dropping the solvent, and after dropping. The state of the surface of was observed. When the solvent resistance is inferior, when the cloth is wiped off with a cloth, the resin component tends to spread to the surroundings. Therefore, whether the solvent resistance is good or not is determined based on whether such a tendency is observed.
(Comparative Example 1)
A fiber reinforced composite material was molded using only a reinforcing fiber base and a liquid thermosetting resin without using a thermosetting resin sheet, and various measurements were performed. First, carbon fiber fabrics CO6343B and 4ply cut so that each side is a square with a side of 300 mm parallel to either warp or weft are laminated on a mold maintained at 100 ° C., and then a peel ply and a resin distribution medium A certain nylon net was laminated. Next, bagging was performed using a nylon film and the pressure was reduced to [atmospheric pressure-0.1] (MPa) using a vacuum pump, and then a liquid thermosetting resin was injected. The injection was completed 5 minutes after the start of injection, and demolding was started 25 minutes after the start of injection to obtain a fiber-reinforced composite material. During molding, the mold temperature was kept at 100 ° C. The time (molding time) from the start of setting of the carbon fiber fabric to the mold until the completion of the demolding was 40 minutes, which was a sufficiently short time.

It was found that the surface roughness of the fiber reinforced composite material was 1.6 μm, which was not smooth.
Example 1
Using a thermosetting resin sheet, a fiber reinforced composite material was molded, and various measurements were performed. First, a square thermosetting resin sheet having a side of 300 mm was set in a mold maintained at 100 ° C. Thereafter, a fiber-reinforced composite material was obtained in the same procedure as in Comparative Example 1. However, injection was started 10 minutes after setting the thermosetting resin sheet. The Tg of the thermosetting resin sheet after curing at 100 ° C. for 10 minutes was 25 ° C., which was lower than Tm (MAX) −30 = 70 (° C.). In addition, the time (molding time) from the start of setting of the thermosetting resin sheet to the mold until the completion of demolding was 52 minutes, which was a sufficiently short time.

The results of the solvent resistance test of the fiber reinforced composite material were all good. Further, the surface roughness of the fiber reinforced composite material was 0.80 μm and was sufficiently smooth.
(Example 2)
Using a thermosetting resin sheet, a fiber reinforced composite material was molded, and various measurements were performed. First, a square thermosetting resin sheet having a side of 300 mm was set in a mold maintained at 100 ° C. Thereafter, a fiber-reinforced composite material was obtained in the same procedure as in Comparative Example 1. However, injection was started 40 minutes after setting the thermosetting resin sheet. The Tg of the thermosetting resin sheet after curing at 100 ° C. for 40 minutes was 82 ° C., which exceeded Tm (MAX) −30 = 70 (° C.). Moreover, the time (molding time) from the start of setting of the thermosetting resin sheet to the mold until the completion of demolding was 72 minutes, which was a sufficiently short time.

The results of the solvent resistance test of the fiber reinforced composite material were all good. Further, the surface roughness of the fiber reinforced composite material was 0.64 μm and was sufficiently smooth.
(Example 3)
Using a thermosetting resin sheet, a fiber reinforced composite material was molded, and various measurements were performed. First, a 300 mm square thermosetting resin sheet and carbon fiber fabric CO6343B, 4ply cut so that each side becomes a 300 mm square parallel to either warp or weft, are pre-laminated. The body was made. Next, a pre-laminated body was set in a mold maintained at 100 ° C. so that the thermosetting resin sheet was in contact with the mold surface, and then a fiber-reinforced composite material was obtained in the same procedure as in Comparative Example 1. However, injection was started 40 minutes after setting the preliminary laminate. The Tg of the thermosetting resin sheet after curing at 100 ° C. for 40 minutes was 82 ° C., which exceeded Tm (MAX) −30 = 70 (° C.). Further, the time (molding time) from the start of setting of the pre-laminated body to the mold until the completion of demolding was 67 minutes, which was a sufficiently short time.

  The results of the solvent resistance test of the fiber reinforced composite material were all good. Further, the surface roughness of the fiber reinforced composite material was 0.66 μm and was sufficiently smooth.

  Comparative Example 2 Gelcoat NR-AC0001P was uniformly applied to a thickness of 350 μm on a mold maintained at 60 ° C., and then allowed to stand for 60 minutes to cure the gelcoat. It took 10 minutes to apply the gel coat. After the mold temperature was raised to 100 ° C. over 20 minutes, a fiber-reinforced composite material was obtained in the same procedure as in Comparative Example 1. The time (molding time) from the start of application of the gel coat to the mold until the completion of demolding was 115 minutes, which was not a short time.

  The surface roughness of the fiber reinforced composite material was 1.20 μm and was relatively smooth.

By the production method of the present invention, a fiber reinforced composite material having a smooth, heat-resistant, and solvent-resistant surface can be molded in a short time, and automobiles that are often seen directly by the user and require designability It can use suitably for manufacture of outer plate members, such as an outer plate.

It is a profile of the surface unevenness | corrugation by a contact-type surface roughness meter used when calculating surface roughness.

Claims (15)

The component [C] is injected into a mold in which the following components [A] and [B] are set, and after impregnating and curing the component [A], the molded product is demolded. A method for producing a fiber-reinforced composite material.
[A] Reinforcing fiber substrate [B] Thermosetting resin sheet [C] Liquid thermosetting resin composition The method for producing a fiber-reinforced composite material according to claim 1, wherein the component [B] has a thickness in the range of 50 to 800 µm. The manufacturing method of the fiber reinforced composite material in any one of Claim 1 or 2 in which component [B] contains an epoxy resin. The manufacturing method of the fiber reinforced composite material of Claim 3 in which a component [B] contains a bisphenol A type epoxy resin or a bisphenol F type epoxy resin. The manufacturing method of the fiber reinforced composite material in any one of Claims 1-4 in which structural element [B] contains a thermoplastic resin. The manufacturing method of the fiber reinforced composite material in any one of Claims 1-5 in which component [B] contains the support body which consists of at least 1 sort (s) chosen from the group which consists of a textile fabric, a knitted fabric, and a nonwoven fabric. Component [A] contains carbon fiber, The manufacturing method of the fiber reinforced composite material in any one of Claims 1-6 characterized by the above-mentioned. Component [C] contains an epoxy resin, The manufacturing method of the fiber reinforced composite material in any one of Claims 1-7 characterized by the above-mentioned. Before setting component [A], [B] in a type | mold, the preliminary | backup laminated body which laminated | stacked component [B] on the at least single side | surface of component [A] is produced in any one of Claims 1-8. The manufacturing method of the fiber reinforced composite material of description. The method for producing a fiber-reinforced composite material according to any one of claims 1 to 8, wherein the constituent element [A] is set after the constituent element [B] is set in the mold. The method for producing a fiber-reinforced composite material according to any one of claims 1 to 10, wherein the injection of the component [C] into the mold is started within 30 minutes after the component [B] is set in the mold. After setting the component [B] in the mold, the injection of the component [C] into the mold is started in a state where the glass transition temperature (Tg) of the component [B] satisfies the following condition (1) Item 12. A method for producing a fiber-reinforced composite material according to any one of Items 1 to 11.
Tg ≧ Tm (MAX) -30 (1)
Tg: Glass transition temperature (° C.) of component [B]
Tm (MAX): Maximum mold temperature (° C) Tm ± with respect to a specific temperature Tm included in the range of 60 to 180 ° C. throughout the entire process from the start of setting of the components [A] and [B] to the completion of demolding of the molded product. The method for producing a fiber-reinforced composite material according to any one of claims 1 to 12, wherein the mold temperature is maintained at 10 ° C. The manufacturing method of the fiber reinforced composite material of Claim 13 which satisfy | fills the following conditions (2)-(4).
ti ≧ 10 (2)
tm ≦ 60 (3)
1 <tm / ti ≦ 6.0 (4)
ti: Time from the start of injection to the end of injection (minutes)
tm: Time from the start of injection to the start of demolding the molded product (minutes) The fiber reinforced composite material manufactured using the method in any one of Claims 1-14.

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