JP2000263668A - Sandwiched panel made of frp and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain high mechanical physical properties by incorporating a hollow box-like material in a gap. SOLUTION: The sandwiched panel 1 contains a hollow box-like material 4 in the panel formed of upper and lower plates 2 and ribs 3. The ribs 3 may be integrally molded with a sidewall of the material 4. A material of a rib structure 3 can be formed of an FRP, a metal, timber or the like, and the material 4 is formed of a thermoplastic resin or a thermosetting resin. The method for manufacturing the panel comprises the steps of disposing reinforcing fiber on a mold, disposing the box-like material wound with the fiber on the mold, disposing the fiber, then covering the entirety with a vacuum film base material, then evacuating in vacuum therein, pouring the resin, and impregnating the fiber with the resin. Thus, since the material is contained in the gap between both the plates, the material is functioned as a core material and/or the rib, and hence light weight properties can be maintained while assuring the entire mechanical properties high.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a sandwich panel made of FRP and a method of manufacturing the same, and more particularly to a lightweight and low-cost sandwich panel made of FRP and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, sandwich panels used as various structures have a structure in which, for example, a foam or a heat insulating material is used for a core, and the core is sandwiched between metal plates or wooden plates. However, when a metal plate is used, the rigidity and strength are high, but the weight is heavy and the assembly takes time. On the other hand, when a wooden board is used, it is lightweight but has low rigidity and strength when used as a structure, and it is difficult to use as a structure. .

[0003] In order to solve these drawbacks, there have been proposed FRP plates having higher specific strength and specific elastic modulus than metals, particularly CFRP plates using carbon fibers.

[0004]

[0005] FRP sandwich panels are used in various fields, particularly in civil engineering and construction materials, because of their light weight, high strength and high rigidity. Foams are commonly used as core materials in sandwich panels.
Generally, organic foams such as urethane foam, polystyrene foam, and phenol foam are widely used as the core material, but all of these foam materials need to be manufactured using a mixture of a polymer and a foaming agent as a raw material. As a result, manufacturing costs are high, which has increased the manufacturing costs of sandwich panels.

In particular, in recent years, low-cost and high-strength F
Vacuum RT attracting attention as a molding method that can produce RP
M method (Resin Transfer Moldin)
In order to use g), the core material must be able to withstand the pressure of vacuum, and in order to obtain high compressive strength, the density of the core material must be high. In addition, the cost was higher and the weight was higher. Therefore, as a result, even if a low cost method is used as a molding method, the manufacturing cost of the sandwich panel using the same is high due to the high price of the core material.

An object of the present invention is to manufacture a lightweight FRP sandwich panel having sufficiently high mechanical properties at a low cost, and particularly to a FRP sandwich panel suitable for building materials such as roofing materials.
An object of the present invention is to provide an RP sandwich panel and a method of manufacturing the same.

[0007]

In order to solve the above-mentioned problems, a sandwich panel made of FRP according to the present invention comprises a pair of plates including FRP disposed at least on one side thereof with a gap, and a rib for joining the two plates to the gap. An FRP sandwich panel in which a structure is interposed, wherein a hollow box-like material is included in the gap.

As the material of the rib structure, FRP, metal, wood or the like can be used, and it is preferable that the rib structure is arranged and incorporated at the same time as the molding of the pair of plates.

The size of the gap between the pair of plates may be substantially constant in the direction in which the plates extend, or may vary.

The plate itself may have a simple flat plate shape. For example, at least one of the plates has a folded plate shape in which peaks and valleys are alternately arranged. You can also. The peaks and / or valleys may be linearly extended in a certain direction, or may be three-dimensionally formed in a pyramid shape or the like.

The rib structure can have various cross-sectional shapes, but can also be configured as a truss or ramen structure.

[0012] As the hollow box-shaped material, any of those made of a thermoplastic resin and those made of a thermosetting resin can be used. Reinforcing fibers may be wound around a box made of these resins so that a box made of substantially FRP is formed after the sandwich panel is formed. If grooves are formed on the surface of the box-shaped material, the resin can be diffused during molding. As for the shape of the box-like material, a rectangular shape or a trapezoidal cross-sectional shape can be used.

In the sandwich panel made of FRP according to the present invention, it is preferable that the matrix resin of at least one plate is made of a phenol resin in order to improve fire resistance. Further, a layer made of a refractory material, for example, a refractory material or a refractory paint may be provided on at least one side.

Further, the sandwich panel made of FRP according to the present invention can be suitably used as a building material such as a roof material. At that time, for the entire FRP roofing material or the entire FRP roofing material unit to constitute the roof,
It can be formed in a three-dimensional shape. For example,
A structure in which at least one plate has a polyhedral three-dimensional shape portion or a structure in which at least one plate has a three-dimensional shape portion having a three-dimensional curved surface portion can be employed. Further, a structure having both of these three-dimensionally shaped portions may be adopted.

[0015] In the method for producing a sandwich panel made of FRP according to the present invention, a reinforcing fiber is arranged on a mold, and a hollow box-like material having the reinforcing fiber wound is arranged at a predetermined position on the reinforcing fiber.
After further arranging the reinforcing fibers, the inside covered with the film substrate is evacuated after covering the whole with the film substrate for vacuum,
The method is characterized by injecting a resin and impregnating the reinforcing fibers.

In the sandwich panel made of FRP according to the present invention as described above, a hollow box-like material is included in the gap between the two plates, and this box-like material also functions as a core material and / or a rib. While maintaining the mechanical properties of the entire sandwich panel at a sufficiently high level, the hollow structure can maintain the overall lightness or can be improved compared to other rib structures. The hollow box-shaped article may be a simple resin molded article before the entire sandwich panel is formed, and thus can be manufactured at low cost.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. First, with regard to the basic technical concept of the present invention, the present inventors have conducted intensive studies on the optimum sandwich panel structure for obtaining a low-cost and high-strength rigidity FRP sandwich panel, and as a result, the sandwich panel It has been found that the above-mentioned problem can be solved by using a hollow box-like material in the gap instead of the core material or a part thereof.

The hollow box-shaped material can be used by the most common hand lay-up method as the FRP molding method instead of the core material at the time of molding. Furthermore, in the vacuum forming method, the internal pressure of the hollow box-shaped material may be the same as the normal air pressure, so even when the whole is covered with a vacuum film substrate and formed, the external pressure and the pressure are balanced, so the box It can be molded without crushing the object.

The material of the hollow box-shaped material may be any material. In particular, a material manufactured by injection molding or blow molding using a thermoplastic resin is very advantageous in terms of cost. Further, a hollow box having a desired shape can be easily formed by injection molding or blow molding. Thus, whatever the shape of the sandwich panel, it can be made by changing the shape of the hollow box. For example, even if the size of the gap of the sandwich panel changes, or if one of the plates has a folded plate shape in which peaks and valleys are alternately arranged, it can be easily manufactured.

Although the size of the hollow box-shaped object may be any size, if the volume is too small, the effect of reducing the weight is less likely to be obtained as compared with the foam core, and therefore, 1,000 cm ³
The above are preferably used. If the volume is too large, there is a structural problem. Therefore, the volume is preferably 100,000 cm ³ or less.

When used in place of the foam core, all or a part of the core is formed into a hollow box,
Cost reduction is possible. Depending on the required properties of the sandwich panel in terms of physical properties, it is possible to use wood, concrete, etc. together with the hollow box-like material as the core material.

At least one of the pair of plates forming the sandwich panel of the present invention is a plate containing FRP for weight reduction. The thickness of this plate is preferably 0.6 to 7 mm. If the thickness is less than 0.6 mm, it is difficult to obtain desired strength and rigidity, and there is a high possibility that a flaw that penetrates the plate due to an impact is generated. On the other hand, if it exceeds 7 mm, the strength and rigidity are sufficient, but there is a disadvantage that the weight becomes very heavy.

Depending on various characteristics required for the sandwich panel, a plate having an integral structure of FRP and metal can be used as the plate. Further, for example, of the plates forming the sandwich panel, the lower surface may be formed of FRP, and the upper surface may be formed of a non-combustible material such as metal, concrete, mortar or the like from the viewpoint of fire resistance.

Glass fibers, aramid fibers, carbon fibers and the like are usually used as the reinforcing fibers of FRP. Carbon fiber is most preferred for obtaining a lightweight and high-strength FRP, but a glass fiber / carbon fiber hybrid is also preferred for balancing cost. As the form of the fiber used, cloth, mat, strand, and the like can be suitably used. Further, any kind of carbon fiber may be used in consideration of the high strength and rigidity of the carbon fiber. However, in view of lower cost, it is most preferable to use a so-called large tow carbon fiber.

For example, the number of filaments per carbon fiber yarn is not less than the usual number of 10,000,
000 to 300,000, more preferably 5
The use of tow-like carbon fiber filament yarns in the range of 0000 to 150,000 yarns has better resin impregnation,
It is preferable because it is more excellent in handleability as a reinforcing fiber base material and further in economic efficiency of the reinforcing fiber base material. Also F
Placing a carbon fiber woven fabric on the surface of the RP structure enhances the design of the surface, which is more preferable. In addition, a reinforcing fiber base is formed by laminating a plurality of layers of reinforcing fibers as necessary or according to required mechanical properties and the like, and the reinforcing fiber base is impregnated with a resin. On the reinforcing fiber layer to be laminated, a fiber layer or a fabric layer aligned in one direction can be appropriately laminated, and the fiber orientation direction can be appropriately selected according to the direction of required strength.

As the FRP resin, a vinyl ester resin, an unsaturated polyester resin, a phenol resin and the like are preferably used. Particularly, for building materials and civil engineering materials, phenol resin is used because of its flammability standard. Most preferably used.

As the structure of the sandwich panel, there is a rib structure in which a pair of plates are arranged with a gap therebetween and the upper and lower plates are joined to the gap. Any structure can be used as long as a hollow box-like object exists in the gap. Good. Further, a sandwich panel in which at least one plate has a folded plate shape in which peaks and valleys are alternately arranged is suitably used depending on the application.

As the shape of the pair of plates, a flat plate shape, a corrugated plate shape, or the like can be used depending on the application. In addition to the fact that the interval between the pair of plates is substantially constant, there is no problem even if the interval changes.

The shape of the rib may be a structure in which each of the ribs extends vertically from the pair of plates and connects the pair of plates, or a rib structure of a truss structure or a rigid frame structure may be used.

When the present sandwich panel is used for building materials and the like, a fire-resistant material may be provided on at least one side from the viewpoint of fire resistance. Refractory materials include rock wool molded plate, resin foam, rock wool felt material, ceramic fiber felt material, fire resistant paint,
A foaming paint, a fire-resistant sealant, or the like, or a combination thereof is preferably used.

The method for manufacturing a sandwich panel according to the present invention will be described below in order. (1) Reinforcing fibers are arranged on a mold. At this time, as a method of arranging the reinforcing fibers, there is a method of arranging the fibers as they are on a mold, but it is more preferable to arrange the fibers which have been made into a cloth in advance from the viewpoint of production efficiency.

(2) A hollow box-shaped material wound with reinforcing fibers is arranged in the form of reinforcing fibers. As the hollow box-shaped material, a material formed by blow molding, injection molding, or the like according to a desired shape of the sandwich panel can be used. Reinforcing fibers may be inserted between the hollow box-shaped objects so as to become ribs after resin injection. Instead of inserting the reinforcing fiber, a reinforcing fiber wound around a box may be used as the rib. Depending on the physical properties of the sandwich panel, the core material may be not only a hollow box-shaped material but also an organic foam, wood, concrete or the like in combination with the hollow box-shaped material.

(3) Further, reinforcing fibers to be the upper surface of the sandwich panel are arranged.

(4) The entire molded body is covered with a vacuum film substrate.

(5) The covered interior is evacuated.

(6) A resin is injected into the inside to impregnate the reinforcing fibers. At this time, as an auxiliary means for impregnation, a hollow box-like material or a material obtained by cutting a groove serving as a resin passage on at least one surface of a core material used in combination therewith may be used. In particular, when the size of the molded article is large, such an auxiliary means for resin impregnation is effective.

(7) After the resin is cured, it is released from the mold. Heat may be applied to the curing as needed. Further, after demolding, heat may be further applied as after-curing.

Hereinafter, more specific embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an embodiment of the present invention. The sandwich panel 1 includes a hollow box-shaped object 4 in a sandwich panel formed by upper and lower plates 2 and ribs 3. The rib 3 and the side wall of the hollow box-shaped material 4 may be integrally formed.

FIG. 2 shows another embodiment of the present invention. Sandwich panel 11 shaped like a folded plate
A hollow box 14 is contained in the sandwich panel 11 formed by the upper and lower plates 12 and the ribs 13. The rib 13 and the side wall of the hollow box 14 may be integrally formed.

FIG. 3 shows still another embodiment of the present invention. Upper and lower plates 22 of sandwich panel 21
And the ribs 23, the hollow box-like material 24 and the urethane foam core 25 on one side of the sandwich panel 21
Six layers are formed.

FIG. 4 shows an embodiment of the hollow box-shaped object of the present invention. A groove 32 is formed on the surface (upper and lower surfaces in the illustrated example) of the hollow box 31 shown in FIG. 4, and can function as a resin flow path during molding.

FIG. 5 shows an example in which one of the pair of plates 42a and 42b of the sandwich panel 41 has a folded plate structure, and the gap between both plates changes in the plate extending direction. I have. Reference numeral 43 denotes a rib, and reference numeral 44 denotes a hollow box.
The rib 43 and the side wall of the hollow box-shaped member 44 may be integrally formed.

In the sandwich panel 51 shown in FIG.
A truss structure 53 is provided between the pair of plates 52a and 52b as a rib structure. In addition, an example is shown in which a hollow box-shaped object 54 and a core 55 are provided at appropriate positions inside.

FIG. 7 shows that the sandwich panel 61 can take various shapes as a whole. In the illustrated example, the sandwich panel 61 has a shape in which pyramid-shaped portions 62 are connected.

In particular, the sandwich panel 71 formed into a semicircular shape as shown in FIG. 8 is more suitable for use as a roofing material. 7, reference numeral 72 denotes a pair of plates, 73 denotes a rib, and 74 denotes a hollow box.

As described above, the FRP sandwich panel according to the present invention can take various forms. In particular, it can be made into various forms suitable for building materials such as roofing materials, and as described above, it can be provided with sufficient mechanical properties while being lightweight, and can be manufactured at low cost.

[0047]

As described above, according to the sandwich panel made of FRP and the method of manufacturing the same according to the present invention, a sandwich panel which is low in cost and has sufficient physical properties can be provided.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of an FRP sandwich panel according to an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view of an FRP sandwich panel according to another embodiment of the present invention.

FIG. 3 is a partial cross-sectional view of an FRP sandwich panel according to still another embodiment of the present invention.

FIG. 4 is a perspective view showing an example of a hollow box-shaped object.

FIG. 5 is a partial cross-sectional view of an FRP sandwich panel according to still another embodiment of the present invention.

FIG. 6 is a partial sectional view of an FRP sandwich panel according to still another embodiment of the present invention.

FIG. 7 is a partial perspective view of an FRP sandwich panel according to still another embodiment of the present invention.

FIG. 8 is a perspective sectional view of an FRP sandwich panel according to still another embodiment of the present invention.

[Explanation of symbols]

1, 11, 21, 41, 51, 61, 71 FRP sandwich panel 2, 12, 22, 42a, 42b, 52a, 52b, 7
2 plate 3, 13, 23, 43, 73 rib 4, 14, 24, 44, 54, 74 hollow box 25, 55 core 26 refractory 53 truss structure 62 pyramid

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) E04C 2/20 E04C 2/30 L 2/30 B29C 67/14 L // B29K 61:04 B29L 31:10 F-term (reference) 2E001 DE01 FA16 GA23 GA42 GA48 HD11 HD12 JA29 KA01 2E162 CD05 FA20 GA05 GA07 GB00 4F100 AD11A AK01A AK33A AR00B BA01 BA02 BA10A BA10B DC05A DC07A DG01A DH02A EC182 EH3B12 EJ082 EJ242 EJ082 EJ082 EJ242 EJ242 AD16 AD17 AD18 AG28 AH43 AH47 AR14 HA06 HA09 HA14 HA22 HA33 HA35 HB01 HB11 HC17 HF23 HK16 HK31 HM02 HT26

Claims (17)

[Claims] 1. An FRP sandwich panel in which a pair of plates containing FRP is disposed on at least one side with a gap, and a rib structure for joining the two plates is interposed in the gap. An FRP sandwich panel characterized by being included in a gap. 2. The FRP sandwich panel according to claim 1, wherein the size of the gap is substantially constant in a plate extending direction. 3. The FRP sandwich panel according to claim 1, wherein the dimension of the gap changes in the plate extending direction. 4. The at least one plate is formed in a folded plate shape in which peaks and valleys are alternately arranged.
3. The sandwich panel made of FRP according to any one of 3. 5. The sandwich panel made of FRP according to claim 1, wherein the hollow box-shaped material is made of a thermoplastic resin. 6. The FRP sandwich panel according to claim 1, wherein the hollow box-shaped material is made of a thermosetting resin. 7. The volume of the hollow box-shaped object is 1000 cm ³
The sandwich panel made of FRP according to any one of claims 1 to 4, characterized in that: 8. The method according to claim 1, wherein the matrix resin of at least one of the plates is a phenol resin.
7. The sandwich panel made of FRP according to any one of 7. 9. The carbon fiber as a reinforcing fiber of the FRP of at least one of the plates.
The sandwich panel made of FRP according to any one of the above. 10. The reinforcing fiber having a filament number of 10,
10. It has tow-like carbon fiber filament yarns in the range of 000 to 300,000 yarns.
FRP sandwich panel. 11. The F according to claim 1, wherein the rib structure comprises a truss or a ramen structure.
RP sandwich panel. 12. The FRP sandwich panel according to claim 1, wherein a refractory material is provided on at least one side. 13. The sandwich panel made of FRP according to claim 1, wherein the hollow box-like object is a rectangular parallelepiped. 14. The sandwich panel made of FRP according to claim 1, wherein the cross section of the hollow box-shaped object is trapezoidal. 15. The FRP sandwich panel according to claim 1, wherein a groove is formed on any one surface of the hollow box-shaped material. 16. The F according to claim 1, wherein
FRP roofing material using RP sandwich panels. 17. A reinforcing fiber is placed on a molding die, a hollow box-like material in which the reinforcing fiber is wound is placed at a predetermined position on the reinforcing fiber, and the reinforcing fiber is further placed. A method of manufacturing a sandwich panel made of FRP, comprising: evacuating the inside covered with a film substrate after covering with a material, and injecting a resin to impregnate the reinforcing fibers.