JPH03247421A - Production of compositely sandwiched mold excellent in design property - Google Patents

Abstract

PURPOSE:To efficiently obtain a compositely sandwiched mold which is lightweight and high in strength and rigidity and excellent in design properties by providing a patterned and/or colored member in a range of the whole surface or partially around the core material or reinforcing fiber or between the reinforcing fiber layers and integrally molding the member, the core material and the reinforcing fiber with transparent thermosetting resin. CONSTITUTION:Reinforcing fiber 22 is provided around the core material 21 to form a preform, and pattern member 23 is partially placed on the reinforcing fiber 22. A suitable pattern 24 is fitted to the pattern member 23 and coloring different from the color of the pattern member 23 is performed. The preform with the pattern member 23 fixed thereto is filled into the cavity 2 of a mold and this mold is closed. Transparent thermoplastic resin is introduced into the cavity 2 from an introduction port 4 of resin. This resin is introduced in a degree such as thermosetting resin is finely overflowed from a discharge port 5 of overflow. The mold 1 is held at the temp. preferable to cure the thermosetting resin for a prescribed time. The thermosetting resin in the cavity 2 is cured to integrally mold the core material 21, reinforcing fiber 22 and the pattern member 23. The obtained compositely sandwiched molded form is taken out from the mold 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a composite sandwich molded product that is lightweight, has high strength and rigidity, and has an excellent design.

[Prior art] Conventionally used methods to improve the design of composite sandwich molded products having a fiber-reinforced resin layer on the outside of the core material include (a) painting the surface of the molded product (painting method); ).

(b) Applying a patterned and/or colored film to the surface of the molded product (film application method).

(1) Adding pigment to thermosetting resin to add color to the resin (dispersion method).

(1) Painting internal members, such as foam core materials, or using colored core materials and reinforcing the outside with transparent fibers (internal coloring method)
.

(E) Combining reinforcement 1iAM of different colors, such as black carbon fiber and yellow aramid fiber, to weave a pattern (
hybrid fiber method).

etc. are used alone or in combination of two or more.

[Problems to be Solved by the Invention] However, the conventional techniques (a) to (e) above have the following drawbacks. That is, the painting method (a) and the film method (b) require labor and inevitably increase production costs, and have the disadvantage that scratches on the surface of the molded product degrade the design. (2) The doped method is resistant to surface scratches because the resin itself is colored, but it can only be colored in a single color. Furthermore, when changing colors, it is necessary to clean the resin injection system or prepare a resin injection system for each color, making this method unsuitable for high-mix, low-volume production. In the internal coloring method (1), when painting an internal member, a coating film is interposed between the internal member and the thermosetting resin,
It has the disadvantage of lowering the adhesive strength at the interface, and when a colored core material is used, it has the same disadvantages as the above-mentioned doping method when changing the color. Furthermore, because of the need to convey the internal color to the surface layer of the molded product, the reinforcing fibers that can be used are limited to transparent materials, which has the disadvantage of being subject to restrictions in terms of molded product design. In the hybrid fiber method (e), the pattern required for design and the pattern emitted from the reinforcing equipment for strength design may differ, and it usually presents a relatively simple repeating pattern. Expression is difficult.

The present invention has been made to solve the above-mentioned drawbacks.
The purpose of the present invention is to provide a method for efficiently manufacturing a composite sandwich molded product that is lightweight, has high strength and rigidity, and has excellent design.

[I! Means for Solving the Problem] According to the present invention, in order to achieve the above object, reinforcing fibers are arranged around a core material to form a preform, the preform is loaded into a cavity in a mold, After the mold is closed, a curable resin is injected into the cavity and hardened to form the molded product, and the molded product is taken out from the mold. around the material or reinforcing fibers or between the reinforcing fiber layers, over the entire surface or partially, and integrally molding the member, the core material, and the reinforcing fibers with a transparent curable resin. Provided is a method for manufacturing a composite sandwich molded product with an excellent design.

Further, according to the present invention, in the above method, when disposing the patterned and/or colored member around the reinforcing fibers, by disposing a transparent surface material between the member and the cavity surface, Furthermore, a method for manufacturing a composite sandwich molded product with excellent design is provided.

In the method of the present invention, a preform is made by arranging reinforcing fibers around a core material, the preform is mounted in a cavity in a mold, and after the mold is closed, a curable resin is injected into the cavity. In the method of molding by curing and removing the obtained molded product from the mold, the following means are adopted in order to produce a product with excellent design.

That is, according to the method of the present invention, a patterned and/or colored member (hereinafter abbreviated as "pattern member") is arranged around or between the reinforcing fibers, and the pattern is By integrally molding the component, core material, and reinforcing fiber with transparent curable resin, a thin transparent resin layer exists on the surface of the molded product, and the area where the pattern appears in one color is located inside the transparent surface layer of the molded product. As a result, molded products that are resistant to external damage, robust, and have an excellent design are manufactured.

Furthermore, in the above method, it is not necessary to make the surface material transparent in the air, as long as it becomes transparent when embedded in a transparent resin; a typical example of this is glass lIN). By placing it between the inner surfaces of the mold, a thin transparent resin layer is present on the entire surface layer of the molded product, and when the surface material and pattern member are placed inside this layer, the pattern and/or color becomes deeper. be able to. Also, if the surface of the pattern member is smooth, if there is no surface material, the pattern member and the inner surface of the mold will stick together, and the transparent resin will only partially penetrate, which is not aesthetically pleasing. The removal of air bubbles, etc., and the infiltration of the resin are promoted, and as a result, defects such as voids can be removed from the surface, and a molded product with better design can be obtained.

The core material used in the method of the present invention may be any material commonly used for composite sandwich molded products, and foam (plastic foam), balsa wood, and honeycomb skin layer materials are preferable, and foam is particularly easy to obtain at low cost. It is economical, and foams made from foamed polyurethane, phenol, polystyrene, polyethylene, polypropylene, vinyl chloride, and polyimide resins can be used depending on the purpose.

In order to ensure strong adhesion between the core material and the thermosetting resin, it is necessary to roughen the surface of the core material appropriately or to process the surface layer of the foam to allow the resin to penetrate into the interior of the cut cells (anchor effect). method is preferred. It is said that it is preferable for the core material produced by conventional coating methods to have a smooth surface layer because it improves color development, but in the method of the present invention, it is better that the surface layer of the core material is not smooth, and this is a major difference between the two methods. be.

The reinforcing fibers arranged around the core material in the method of the present invention can be made of any material and in any form depending on the purpose, such as transparent glass fibers, carbon fibers, ceramic fibers, aramid fibers, etc. fiber, ultra-high strength polyethylene fiber,
Metal fibers, nylon fibers, polyester fibers, etc., singly or in combination of two or more, arranged in one direction, woven fabrics, non-woven fabrics, mats.

It can be used in the form of a braid or the like.

It is preferable that the reinforcing fibers cover almost the entire circumference of the core material, but depending on the case, they may cover only a part of the core material.

Moreover, it goes without saying that the reinforcing fibers are not limited to one layer, but may be provided in multiple layers.

The size of the preform with reinforcing fibers arranged around the core material,
Although the shape is arbitrary, it is preferable that the molded product has a surface that exhibits design, so the shape of the preform is also preferably one that has at least one flat or curved surface.

As the curable resin, a liquid molding resin is used, and a resin composition that is cured by heating or reaction to become a substantially transparent cured resin, such as an epoxy resin.

Unsaturated polyester resins and other curable resins are used.

The mold is not limited to metal, but can be made of any material such as resin, wood, or ceramic depending on the molding temperature.

The above-mentioned pattern member used in the method of the present invention is preferably made of a thin material such as paper, cloth, net, film, or metal foil, on which patterns and colors can be easily applied. It can be applied by drawing, printing, etc., or the photograph can be used as is. The color can be changed depending on the purpose, such as a uniform color on the entire surface, a printed pattern, or a patterned pattern. Of course, the pattern includes names, initials, etc., but if these patterns are used in a suitable combination, the design will be more excellent.

In addition, by using paper with numbers printed on it, the serial number etc. can be easily embedded, which will not disappear forever and is effective for quality control including the user.

It is desirable to replace pattern materials with colors or designs that dissolve in transparent hardening resin with insoluble ones, but when using them, laminate the pattern materials with a film, etc. to prevent the colors from dissolving. Some effort is needed.

Furthermore, the surface material used in the preferred embodiment of the present invention is required to have the ability to guide the pattern and/or color of the lower pattern member to the surface layer without disturbing it, but it does not necessarily need to be transparent over the entire surface. There may be an opaque part as long as it does not impair the design of the lower part.

Surface materials suitable for the present invention include glass, nylon, polycarbonate, etc., and forms include surface mat (also called pale), single braid, net, knit, and woven fabric, each of which can be used as appropriate for the purpose. Can be used depending on.

In order to sufficiently improve the design of the product according to the present invention, it is desirable that the molded product be free from defects such as voids and insufficient wetting of the resin. It is preferable to evacuate the cavity.In particular, in order to spread the resin to areas with complex curved surfaces and areas that are likely to become dead, it is necessary to inject under vacuum and devise ways to break the vacuum after injection.

[Example] Examples of the method of the present invention will be described in more detail below with reference to the drawings.

Figure 1 shows one implementation of the present invention! ! ie! , which represents the state in which a composite sandwich molded product is manufactured using a mold. Second
The figure is a diagram schematically showing details of the preform and pattern member loaded into the mold cavity of FIG. 1.

In Fig. 1, there are two side structures 1a and lb on the mold, a cavity 2 is formed inside the mold, and the mold mating surface 3 can be sealed in a liquid-tight state using an appropriate sealing method. ing. Usually an O-ring.

A flat gasket etc. is used. The mold 1 has a liquid resin injection port 4. A vent/overflow liquid outlet 5 is provided, each connected to a resin injection device, an overflow pipe, and/or an evacuation device if necessary (all not shown). 21, 22 and 23 in FIG. 1 are a core material, a reinforcing fiber, and a pattern member, respectively.

FIG. 2 shows a preform with a pattern member composed of these. In FIG. 2, reinforcing fibers 22 are arranged around a core material 21 to form a preform.
A pattern member 23 is partially placed on top of the pattern member 2 . A suitable pattern 24 is attached to the pattern member 23, and a color different from that of the pattern member 23 is applied to further enhance the design.

To fix the pattern member 23 to the reinforcing wire N22, methods such as applying or spraying an adhesive on the entire or part of the back surface of the pattern member 23, pasting with an adhesive tape, or attaching with a transparent fiber are used.

In the method of the present invention, after the preform with the pattern member 23 fixed as described above is loaded into the cavity 2 of the mold and the mold is closed, the mold is brought to a predetermined temperature as required, and a transparent resin is poured through the resin injection port 4. Inject thermosetting resin into cavity 2,
The preform and pattern member are wetted with resin, and the resin is injected to the extent that the curable resin slightly overflows from the overflow discharge port 5.

Thereafter, the mold 1 is held at a temperature suitable for curing the curable resin for a predetermined period of time, the curable resin in the cavity 2 is cured, and the core material 21. The reinforcing wire @22 and the pattern member 23 are integrally molded, and the resulting composite sandwich molded product is placed in the mold 1.
Take it out.

It goes without saying that the reinforcing fibers 22 may be laminated not only in one layer, but also in multiple layers of different types in order to obtain desired mechanical properties; an example thereof is shown in FIG.

FIG. 3 shows an example in which the method of the present invention is applied to the production of a cylindrical molded product, showing a longitudinal section during molding. A pattern member 33 is placed over the entire circumference, and a glass fiber braided body 34 is further placed over the pattern member 33. The longitudinal rigidity of the cylindrical molded product is greatly reduced by the unidirectionally arranged carbon fiber sheet material 32 on the inside, and the torsional rigidity is increased by the glass fiber braided body 34 arranged on the outside. expands and contracts in the longitudinal direction of the cylinder, and by pulling it in the longitudinal direction, the inner pattern member 33 is pressed inward and also serves to fix the pattern member 33. In this example,
Since the braided body 34 is made of glass fiber, the pattern and/or color of the pattern member 33 appears on the surface. In some cases, the pattern member 33 can be placed on the outside and the braided body 34 can be placed on the inside as shown in FIG. The material of the pattern member 33 is naturally limited by its surface smoothness, resin permeability, etc.

FIG. 5 shows an example in which a pattern member 35 with a smooth surface such as a film image and poor or no oil permeability is used for a flat molded product. By placing a transparent surface material 36 slightly larger than the size of the pattern member 35, for example, a surface mat made of glass fiber, on the upper side of the pattern member 35, the transparent resin is coated on the upper surface of the pattern member 35, giving it a deep appearance. As the pattern and/or color emerges, the surface material 3
Since the pattern member 35 is sandwiched between 6 and the reinforcing member 37, t! 4. There is no risk of the pattern member 35 moving during the injection of fat, and since there is a surface material 36 on the outside of the pattern member 35, even if the outer surface of the molded product is scratched, the damage will not spread to the inside, creating a durable design. It becomes a molded product.

Note that the material of the pattern member 33 is paper or woven cloth.

When using a material that allows resin to pass through the thickness in the thickness direction, such as a non-woven fabric, it may be placed on the surface layer of the molded product as shown in Figure 4.
It may be placed on the innermost layer as shown in the figure.

When the pattern member 33 is arranged in the innermost layer as shown in FIG. 6, although there are restrictions on the reinforcing fibers 32 and 34 arranged on the outside, since the core material 31 can be wrapped in the pattern member 33,
If the surface of the core material is rough, for example, if the cut surface of the foam foam is exposed, there is a risk that the reinforcing fibers will get caught in the unevenness and the fiber arrangement will be disturbed. The advantage is that the core material can be coated without damaging the fibers. In this case, since the resin has sufficiently penetrated into the pattern member 33, there is no problem with the adhesion between the core material 31 and the reinforcing fibers 32 and 34.

As shown in FIG. 6, if a non-permeable material such as a film is used as the pattern member 33, a core material that dissolves in the resin before the resin hardens, for example, in the case of a combination of polystyrene foam and unsaturated polyester, will not only improve the design but also the core material. It is preferable because it has a resin blocking function for the material.

If you use a pattern material with color blocking ability that does not show the color of the lower side, the color of the reinforcing fibers on the lower side, such as the black of carbon fiber, will not be exposed and the color will be excellent. When placed, the color develops as if pigment were added to the resin.

If a net-like material is used as the pattern member, a grid or striped pattern that is easily erased by painting can be easily realized.

For comparison, FIG. 7 shows an example of a coating method, which is one of the conventional techniques. It can be easily imagined that in products manufactured by conventional painting methods, the coating film 41 is placed on the surface layer of the molded product consisting of the core material 43 and the mN reinforcing layer 42, and is vulnerable to external damage.

Although the above-mentioned embodiments have been explained using closed molds, the method of the present invention can also be applied to cases where essentially open molds are used, such as the vacuum bag method.

The present invention can also be applied to the case where a gel coat is applied to the surface of the mold, and the pattern member may be fixed to the gel coat portion or fixed to the preform side, either method may be used.

[Effects of the Invention] As is clear from the above description, according to the method of the present invention, it is possible to efficiently produce a composite sandwich molded product that is lightweight, has high strength and rigidity, and has an excellent design.

The first advantage is that because the pattern and/or color of the product is placed inside the surface layer of the molded product, one color of the pattern will not be damaged even if there is external damage such as abrasion, resulting in excellent design. That's true. In particular, this effect is further enhanced when a surface material such as glass fiber is coated on the pattern member.

The second point is that the pattern and/or color of the molded product can be changed simply by changing the patterned and/or colored pattern member, requiring only a small amount of additional labor and providing great economic benefits. Furthermore, by covering the entire outer surface of the molded product with the colored pattern member, it is possible to easily create a dyed or printed pattern without a large increase in cost.

The third point is a pattern material with a detailed pattern of 9 colors, such as a photo,
It is possible to easily embed graphics, etc., and to provide a molded product with a new and excellent design, which was difficult to achieve with conventional techniques.

The fourth point is that the applications of molded products to which the present invention can be applied are very wide, and designs suitable for these applications can be provided.

Applications of the molded product according to the present invention include automobile bodies and parts, building materials, furniture, sporting goods, office supplies, parts of home appliances, bags, etc. The method of the present invention is particularly suitable for sports equipment that requires particularly detailed design, such as skis, golf clubs, tennis rackets, bats, surfing boards, sailboards, and their parts (balls, daggers,
skeg, etc.), bicycles, water skis, etc. Fig. 1 is a vertical sectional view during molding showing the concept of the manufacturing method of the present invention, and Figs. 2 and 5 are pattern members.

A sketch showing an example of various arrangements of reinforcing fibers and core materials, and FIGS. 3, 4, and 6 are cross-sectional views showing examples different from FIG. 1. FIG. 7 is a diagram showing a typical example of a product produced by the conventional method.

In the figure, 21.31...core material, 22.32.34
．． 37... Reinforcing fiber, 23.33.35... Pattern member, 25.36... Surface material.

Figure 2 Third figure 6th figure Fourth figure Figure 7 Fifth figure

Claims (2)

[Claims] (1) Reinforcing fibers are arranged around the core material to form a preform, the preform is loaded into a cavity in a mold, the mold is closed, and a curable resin is injected into the cavity and hardened to form the mold. In the method for manufacturing a composite sandwich molded product in which the molded product is taken out of the mold, a patterned and/or colored member is placed over the entire surface around the core material or reinforcing fibers or between the reinforcing fiber layers. fully or partially disposed;
A method for manufacturing a composite sandwich molded product with excellent design, characterized by integrally molding the member, a core material, and reinforcing fibers using a transparent curable resin. (2) The design according to claim (1), wherein when a patterned and/or colored member is arranged around the reinforcing fibers, a transparent surface material is arranged between the member and the cavity surface. A method for producing superior composite sandwich molded products.