JP2012162647A - Fiber-reinforced plastic molded article and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fiber-reinforced plastic molded article which contains at least a glass fiber, and whose cut surface formed by a machining process has smoothness without being coated with a coating material or the like, thereby prevents irregular reflection light rays, and exhibits the substantially same resin color as the color of a pigment incorporated into a matrix resin, and to provide a method for producing the same.SOLUTION: The fiber-reinforced plastic molded article includes a pigment in a matrix resin and is characterized in that its cut surface formed by a machining process has an arithmetic average roughness (Ra) of ≤0.3 μm by being polished or coated with a resin having translucency. The method for producing the molded article is also provided.

Description

  The present invention relates to a fiber reinforced plastic molded article having at least glass fiber as a reinforcing fiber and a pigment in a matrix resin, and without applying paint or the like to the cut surface by machining, white by irregularly reflected light on the cut surface by machining The present invention relates to a fiber reinforced plastic molded article that can prevent the formation of the resin and can obtain almost the same resin color as that of the pigment contained in the matrix resin on the cut surface, and a method for producing the same.

  A fiber-reinforced plastic molded product is obtained by molding using at least one type of reinforcing fiber. Various fibers such as carbon fibers and glass fibers are used as reinforcing fibers, and various plastics have been proposed for plastic parts, mainly thermosetting resins. There are various combinations, and there are fiber-reinforced plastic molded products and methods for producing the same according to the combination.

  Among these combinations, there are particularly many combinations of carbon fibers and glass fibers. Among these, glass fiber has characteristics that are advantageous compared to carbon fiber in terms of impact strength and production cost, although it has a large specific gravity when compared with carbon fiber and does not reach the mechanical properties, especially in terms of elastic modulus. Therefore, it is possible to obtain a fiber-reinforced plastic molded product having a higher value than when both are used alone by combining them so as to compensate for the disadvantages of both.

  For example, as one of the manufacturing methods for providing a rod-like fiber-reinforced plastic molded article having a rectangular cross section with high strength and low cost, carbon fiber is disposed in the outermost layer of the rectangular cross section and glass fiber is disposed in the center of the cross section. Discloses a manufacturing method in which two types of reinforcing fibers are combined and pultruded (see Patent Document 1).

  In addition, as one of methods for providing a bonding structure that can prevent an electrolytic corrosion reaction (galvanic corrosion) between structures in a bonding structure between a carbon fiber reinforced plastic structure and a metal structure, an electrically insulating layer ( For example, a method of manufacturing a carbon fiber reinforced plastic structure including a glass fiber reinforced plastic layer) and bonding it to a metal structure so as to interpose an electrically insulating layer is disclosed (see Patent Document 2).

  In the example of Patent Document 1 described above, a matrix resin directly mixed with a pigment is injected into a resin impregnation tank, and a plurality of types of fibers are impregnated in the resin impregnation tank. A method of manufacturing fiber reinforced plastics that are identical to each other is disclosed. However, when the fiber colors of the plurality of types of reinforcing fibers used are different, for example, by observing the cross section of the rod-like fiber reinforced plastic molded product member according to the example of Patent Document 1, the fiber reinforced plastic layer containing glass fibers and the carbon fibers are In the fiber reinforced plastic layer to be included, since the resin color of each layer looks different, there is a problem that the design property is deteriorated.

  Further, even in a fiber reinforced plastic molded product containing a pigment in a matrix resin, if the smoothness is not sufficiently maintained as shown in FIG. The resin color almost the same as the pigment contained in the matrix resin could not be obtained, and the surface quality after the cutting process was not improved.

  On the other hand, there is a method of obtaining an intended resin color by applying a paint having the same color as the pigment contained in the matrix resin as shown in FIG. However, even if this method is used, it takes time to dry and cure the coating film, and the coating film may be peeled off due to deterioration over time, and the molded product is used in a vacuum or a clean room. In some cases, the use environment may be contaminated by the volatilization of the solvent component from the coating film.

JP 2009-173026 A Japanese Patent Laid-Open No. 11-123765

  Therefore, the object of the present invention is to cut the cut surface of the fiber reinforced plastic molded product without coating it with paint, etc. to prevent irregular reflection light and cut almost the same resin color as the pigment contained in the matrix resin. The object is to provide a fiber-reinforced plastic molded article having improved surface quality.

In order to solve the above problem, that is, the fiber-reinforced plastic molded article of the present invention is
(1) A fiber reinforced plastic molded article including at least glass fiber as a reinforced fiber and a pigment in a matrix resin, wherein the arithmetic average roughness (Ra) at the cut surface of the molded article is 0.30 μm or less. Fiber reinforced plastic molded product.
(2) The fiber-reinforced plastic molded product according to (1), wherein the cut surface is polished.
(3) The fiber-reinforced plastic molded product according to (2), wherein the polishing is wet polishing.
(4) The fiber-reinforced plastic molded article according to any one of (1) to (3), wherein a resin having translucency is applied to the cut surface.
(5) The fiber-reinforced plastic molded product according to any one of (1) to (4), which is a pultruded molded product.
(6) In a method for producing a fiber-reinforced plastic molded article in which at least glass fiber is used as a reinforcing fiber and the matrix resin contains a pigment, the cut surface of the molded article has an arithmetic average roughness (Ra) of 0.30 μm or less. A method for producing a fiber-reinforced plastic molded product.
(7) The method for producing a fiber-reinforced plastic molded article according to (6), wherein the cut surface is polished.
(8) The method for producing a fiber-reinforced plastic molded product according to (7), wherein the polishing is wet polishing.
(9) The method for producing a fiber-reinforced plastic molded product according to any one of (6) to (8), wherein a translucent resin is applied to the cut surface.
(10) The method for producing a fiber-reinforced plastic molded product according to any one of (6) to (9), which is molded by a pultrusion method.
It is.

  According to the present invention, since the cut surface of the fiber reinforced plastic molded article containing at least glass fiber has smoothness, the diffusely reflected light can be prevented and the resin color almost the same as the pigment contained in the matrix resin can be obtained on the cut surface. I can do it.

It is a model perspective view containing the cut surface of the fiber reinforced plastic molded product used for this invention. It is a schematic diagram of the cut surface immediately after trimming of a fiber reinforced plastic molded product. It is a schematic diagram at the time of painting the cut surface of a fiber reinforced plastic molded article with the resin containing a paint or a pigment. (A) It is the schematic diagram after the cut surface grinding | polishing of a fiber reinforced plastics molded product. (B) It is a schematic diagram of the cut surface at the time of apply | coating translucent resin to the cut surface of a fiber reinforced plastics molded product. It is a comparative photograph before and after the grinding | polishing of the cut surface of a fiber reinforced plastic molding.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  The present invention relates to a fiber reinforced plastic molded article 20 formed by combining one or more kinds of reinforcing fibers including at least glass fibers. The fiber reinforced plastic molded article 20 is composed of a fiber reinforced plastic layer 1 containing reinforced fibers other than glass fibers and a glass fiber reinforced plastic layer 2. For example, as shown in FIG. It can be set as the structure pinched | interposed with the fiber reinforced plastic layer 1. FIG. The type of reinforcing fiber other than glass fiber is not particularly limited, for example, roving composed of high strength, high elastic modulus reinforcing fiber such as carbon fiber, aramid fiber, vinylon fiber, alumina fiber, silicon carbide fiber, etc., or a combination thereof. , Cloth, mat, non-woven fabric, and the like. These can be used alone or in combination. Further, the fiber length is not particularly limited, and either continuous fiber or discontinuous fiber may be used. Especially, carbon fiber is suitable as a reinforced fiber which can express light weight, high strength, and high elasticity, and polyacrylonitrile (PAN) type | system | group carbon fiber and pitch type | system | group carbon fiber can be used.

  The laminated structure of the fiber reinforced plastic molded product 20 used in the present invention is such that the reinforcing fiber contained in each reinforcing fiber plastic layer is either glass fiber or reinforcing fiber other than glass fiber as shown in FIGS. As long as it is a single type of fiber that is uniformly dispersed in each layer, the fiber direction, fiber volume content, thickness, etc. of each reinforcing fiber plastic layer are not particularly limited. When a fiber reinforced plastic molded product is used as a structural member that undergoes bending deformation due to external force, it is necessary to arrange fibers with high tensile modulus in order from the outer layer in the same direction within the layer. It is preferable in that the amount of deformation due to can be suppressed. In addition, it is preferable that the reinforcing fiber plastic layers in the cross section of the reinforced fiber plastic molded product are arranged so as to be symmetrical in the vertical and horizontal directions because warpage of the fiber reinforced plastic molded product due to the cross sectional shape can be suppressed.

  It is also preferable to take a structure in which the outer periphery of the laminated fiber-reinforced plastic molded product is covered with a functional material in terms of increasing the surface electrical resistance of the molded product and imparting insulation properties. It does not specifically limit as a functional material, It is preferable also from a manufacture surface to use a fabric. The fiber used for the fabric is not particularly limited as long as it is a thermoplastic synthetic fiber that has a relatively high electrical resistance. From the viewpoint of cost and versatility, polyester-based, polyamide-based, polyolefin-based, polyimide-based, poly-aramid-based, etc. Fiber is preferably used.

  When a thermosetting resin is used as the matrix resin of the fiber-reinforced plastic molded product used in the present invention, the type of the thermosetting resin is cured by heat or external energy such as light or electron beam, and at least partially. If it is resin which forms hardened | cured material in particular, it will not specifically limit, Thermosetting resins, such as an epoxy resin, unsaturated polyester resin, vinyl ester resin, a phenol resin, are used suitably.

  Further, when a thermoplastic resin is used as the matrix resin of the fiber reinforced plastic molded product used in the present invention, the type of the thermoplastic resin is not particularly limited, and polyester such as polyethylene terephthalate resin, polybutylene terephthalate resin, and liquid crystal polyester resin is used. In addition to polyolefin resins such as resin, polyethylene resin, polypropylene resin and polybutylene resin, polyoxymethylene resin, polyamide resin, polycarbonate resin, polystyrene resin, styrene / acrylonitrile copolymer resin, acrylonitrile / butadiene styrene copolymer resin, Acrylate / styrene / acrylonitrile copolymer resin, polymethylene methacrylate resin, polyvinyl chloride resin, polyphenylene sulfide resin, polyphenylene ether resin Polyimide resin, polyamideimide resin, polyetherimide resin, polysulfone resin, polyethersulfone resin, polyetherketone resin, polyetheretherketone resin, etc. can be used, especially polypropylene resin, polyolefin resin, polyamide resin, polycarbonate resin Are preferably used. These copolymers, modified products and blended resins of two or more types can also be used. Further, in order to further improve the impact resistance, a resin obtained by adding an elastomer or a rubber component to the above resin can also be used.

  The pigment mixed in the matrix resin used in the fiber reinforced plastic layer containing glass fiber is not particularly limited, but in order to improve the surface quality, the resin color of the fiber reinforced plastic layer containing the reinforced fiber used in combination It is preferable to use a pigment capable of obtaining the same color. For example, when the reinforcing fiber used in combination is carbon fiber, the resin color of the fiber reinforced plastic layer containing carbon fiber is black, so it is mixed in the matrix resin used for the fiber reinforced plastic layer containing glass fiber. It is desirable to use a pigment that develops black color.

  As a method for molding a fiber reinforced plastic molded product according to the present invention, for example, a hand lay-up method, an autoclave method, a pultrusion molding method, and the like can be molded by any of general fiber reinforced plastic molded product molding methods, It is particularly preferable to use the pultrusion method from the viewpoint of shape and cost in the fiber reinforced plastic molded product as mentioned in the examples.

The polishing machine applied to the wet polishing of the fiber reinforced plastic molded article according to the present invention is not particularly limited, but it is desirable that the apparatus can sufficiently wash away the processing powder generated during polishing when water is supplied. Further, polishing conditions such as polishing time and grain size of the polishing paper are not particularly limited, but the surface roughness after polishing has an arithmetic average roughness (R _a ) based on JISB 0651 (2001) of 0.3 μm or less, preferably 0. It is desirable to set the conditions appropriately so as to be 2 μm. When the arithmetic average roughness exceeds 0.3 μm, it is about the same as the visible light short wavelength (380 nm), and the scattering of light at the cut surface increases, which is not preferable in that the glass fiber reinforced plastic layer looks white. Further, the lower the arithmetic mean roughness, the smoother the surface, so the lower limit value is not particularly specified, but is preferably about 0.003 μm.

  The resin applied to the fiber-reinforced plastic molded product according to the present invention to improve the smoothness of the cut surface by machining is not particularly limited as long as it is transparent and translucent, but is easy to apply. In addition, it is desirable that the applied resin has a short curing time.

  The present invention will be described more specifically with reference to the following examples. However, the following examples are not intended to limit the present invention in any way, and modifications within the scope of the present invention may be made without departing from the spirit of the present invention. It is a range.

Example 1
As a reinforcing fiber combined with glass fiber (glass fiber strand manufactured by Central Glass Co., Ltd., ERS2310-821), PAN-based carbon fiber (carbon fiber “Torayca” (registered trademark) S300-48K and T700SC-24K strand manufactured by Toray Industries, Inc.) ), A vinyl ester resin mixed with carbon black as a pigment was used as a matrix resin, and a fiber-reinforced plastic molded product was molded by a pultrusion molding method.

  As a specific procedure, the above fiber base material is simultaneously immersed in an uncured thermosetting resin mixed with a curing agent, and the fiber base material is distributed by type and excessively impregnated through a squeeze. After scraping, it is heated and cured while passing through a mold space whose central part in the molding direction is held at 145 ° C., and continuously pulled out to obtain a rod shape having a rectangular cross section with a width of 20 mm and a height of 9 mm. A fiber-reinforced plastic molded product was obtained. Under the present circumstances, in the cross section of the rod-shaped member after shaping | molding, the single kind of fiber was disperse | distributed uniformly in each reinforcement fiber plastic layer.

  The rod-like fiber reinforced plastic molded product was cut with a diamond cutter so that the angle formed with the fiber orientation direction was 90 °. Looking at the cut surface, the resin color of the fiber reinforced plastic layer containing glass fibers was white.

  The obtained rod-shaped fiber-reinforced plastic molded product was further cut into a length of 10 to 20 mm in the longitudinal direction, and the cut surface of the molded product 20 was refined by a wet automatic disk polishing machine Refine Polisher, HV (model) : RPO-228KR). As the polishing paper used for wet polishing, a carbomac paper made by Refine Tech Co., Ltd. having a particle size P of 400 was selected, and the polishing paper was affixed to a polishing disk. The cut surface was polished by rotating the polishing disc with the abrasive paper affixed at 200 rpm and pressing the cut surface against the disc for 30 seconds.

The surface roughness of the cut surface of the molded body after polishing was measured using a surface roughness profile measuring machine “Surfcom” (trademark registered) 480A manufactured by Tokyo Seimitsu Co., Ltd. based on JIS B 0651 (2001). The arithmetic average roughness (R _a ) was 0.217 μm.

  It was confirmed that the resin color of the cut surface in this molded product was a substantially uniform black pigment resin color including the glass fiber layer.

(Example 2)
On the cut surface of the fiber reinforced plastic molded product 20 obtained by the same material and molding method as in Example 1, a water-soluble synthetic resin paint Mr. Super clear (glossy) was sprayed. When the surface roughness of the cut surface after spraying this paint was measured based on JISB 0651 (2001), the arithmetic average roughness (R _a ) was 0.201 μm. It was confirmed that the resin color of the cut surface in this molded body was a substantially uniform black pigment resin color including the glass fiber layer.

(Example 3)
A fiber-reinforced plastic molded article was obtained in the same manner as in Example 1 except that the abrasive paper was a carbomac paper having a particle size P of 800 and was affixed to a polishing disk for polishing. When the surface roughness of the cut surface of the obtained molded product was measured in the same manner as in Example 1, the arithmetic average roughness (R _a ) was 0.14 μm. It was confirmed that the resin color of the cut surface in this molded body was a substantially uniform black pigment resin color including the glass fiber layer.

(Comparative Example 1)
The rod-shaped fiber reinforced plastic molded product obtained by each molding method of Examples 1 to 3 was further applied to the cut surface of the fiber reinforced plastic molded product 20 cut to a length of 10 to 20 mm in the longitudinal direction. A fiber-reinforced plastic molded article not subjected to any of the surface treatment methods of Examples 1 to 3 was obtained. When the surface roughness of these cut surfaces was measured based on JISB 0651 (2001), the arithmetic average roughness (R _a ) was 0.534 μm. When the resin color of the cut surface in this molded body was observed, as shown in FIG. 5, the resin color of the glass fiber layer was white, and the molded member had a large contrast with the black color of the carbon fiber layer.

(Comparative Example 2)
The cut surface of the fiber-reinforced plastic molded product 20 obtained by the molding method of Example 1 is the same as the polishing machine used in Examples 1 and 3, and polishing paper having a particle size P of 220 is polished. It was affixed to the disk for rotation, rotated at 100 rpm, and the cut surface was pressed against the disk for 300 seconds for polishing. When the surface roughness of the cut surface after polishing was measured in the same manner as in Example 1 based on JIS B 0651 (2001), the arithmetic average roughness (R _a ) was 0.48 μm. When the resin color of the cut surface in this molded body was observed, as shown in FIG. 5, the resin color of the glass fiber layer was white, and the molded member had a large contrast with the black color of the carbon fiber layer.

  The above Examples 1 to 3 and Comparative Examples 1 and 2 are summarized as shown in Table 1.

  INDUSTRIAL APPLICABILITY The present invention may be widely used when a particularly high design property is required among fiber reinforced plastics including glass reinforced fibers used in automobile and airplane parts, industrial machine parts, and the like.

1 Fiber reinforced plastic layer
2 Glass fiber reinforced plastic layer 3 Cut surface 4 Paint 5 Cut surface after polishing 6 Translucent resin 20 Fiber reinforced plastic molded product

Claims (10)

A fiber reinforced plastic characterized in that, in a fiber reinforced plastic molded article containing at least glass fiber as a reinforced fiber and containing a pigment in a matrix resin, the arithmetic average roughness (Ra) on the cut surface of the molded article is 0.30 μm or less. Molding. 2. The fiber-reinforced plastic molded product according to claim 1, wherein the cut surface is polished. The fiber-reinforced plastic molded article according to claim 2, wherein the polishing is wet polishing. 4. The fiber-reinforced plastic molded product according to claim 1, wherein a translucent resin is applied to the cut surface. The fiber-reinforced plastic molded product according to any one of claims 1 to 4, which is a pultruded product. In a method for producing a fiber-reinforced plastic molded article comprising at least glass fiber as a reinforcing fiber and a pigment in a matrix resin, the cut surface of the molded article has an arithmetic average roughness (Ra) of 0.30 μm or less. Manufacturing method of fiber reinforced plastic molded product. The method for producing a fiber-reinforced plastic molded product according to claim 6, wherein the cut surface is polished. The method for producing a fiber-reinforced plastic molded product according to claim 7, wherein the polishing is wet polishing. The method for producing a fiber-reinforced plastic molded product according to any one of claims 6 to 8, wherein a translucent resin is applied to the cut surface. The method for producing a fiber-reinforced plastic molded product according to any one of claims 6 to 9, which is formed by a pultrusion method.

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