JP3254802B2 - Manufacturing method of FRP - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fiber-reinforced plastic molded article (hereinafter referred to as "FRP") by a pultrusion molding method.
And a method for continuously producing the same.

[0002]

2. Description of the Related Art FRP has many features such as light weight, high strength, and excellent corrosion resistance, and is used in a wide variety of members, such as bathtubs, septic tanks, tanks, as well as automobiles, construction and electrical equipment, as well as housing members. One of the FRP molding methods is a pultrusion molding method.

[0003] The pultrusion molding method is generally a method of impregnating a glass fiber with a thermosetting resin, and then continuously drawing it into a die and shaping and thermosetting to produce an FRP. It has many features such as high productivity
Widely used as structural members such as pipes, angles, channel materials, cable troughs, ladders, and gratings.

In the most common pultrusion molding method, glass fiber rovings are prepared in a roll shape (bobbin) for a predetermined number of rolls, and the glass fiber rovings are drawn out one by one, and each one is separated into an apparatus. And the preform is drawn into the die through several guides provided in the above.

[0005]

However, the above-mentioned general pultrusion method requires a great deal of time and effort for preparation even if one glass fiber roving is passed through several guides. In addition, a number of rovings must be passed through a plurality of defined guides. In addition, since a large number of bobbins wound with rovings are required, a large space is required in the bobbin storage space.

In addition, when glass fiber roving is introduced into a die, there is no lateral constraint, so that a deviation occurs, and the glass content of the obtained molded product tends to be non-uniform depending on locations. There is also.

Further, even in the actual production of FRP, when a plurality of rovings which are continuously transferred are entangled with each other or when the rovings disappear, it is necessary to connect a new roving for each roll. Therefore, troubles occur frequently and work becomes complicated. In particular, in the case of manufacturing a large molded product, it is necessary to use several hundreds of glass fiber rovings, so the situation is more serious, and countermeasures against the above matters are very important issues. ing.

[0008]

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention aims to improve the workability at the time of pultruding and prevent troubles, and to form a high-quality FRP.
An object of the present invention is to provide a method for producing FRP.

The inventor of the present invention has made intensive studies in view of the above problems, and as a result, has used a composite fiber base material in which a roving and a fabric which are aligned in one direction at a predetermined width and a fabric are continuously bonded by a binder. After impregnating the composite fiber substrate with a resin,
It has been found that the above-mentioned problems can be solved if the FRP is continuously manufactured by drawing into a heated die, shaping and curing, and the present invention has been completed.

Next, the present invention will be described in detail.

The composite fiber base material (A) used in the present invention is obtained by bonding a plurality of fiber rovings aligned at a predetermined width to at least one surface of a long fiber fabric so as to be parallel to the long direction. It is the obtained fiber base material.

The composite fiber base material (A) is preferably manufactured continuously as long as possible, and is preferably wound around a bobbin. The length and width are not particularly limited, but are usually 100 to 1000 m in length and about 3 cm to 2 m in width. The thickness is usually 1 to 10 mm. The interval between a plurality of aligned rovings is not particularly limited. For example, 0 (a state in which adjacent rovings are in close contact) to 30
cm, and the impregnation of the thermosetting resin can be performed uniformly.
It is preferable that adjacent rovings are in close contact.

As the structure of the base material (A), a structure in which a fabric is bonded to both surfaces or one surface of a rubbing can be used. Can be used in layers to form a multilayer.

Of course, the fiber base material (A) may be manufactured by selectively adjusting the amounts and ratios of the roving and the fabric, the width and the thickness, etc., according to the specification of the molded article to be obtained. preferable.

As the fabric and roving constituting the substrate (A), any known and commonly used ones can be used. As the substance (fiber) of the base material (A), for example, various organic fibers and inorganic fibers such as glass fiber, carbon fiber, and aramid fiber can be used or used in combination.

The type of fabric and roving fibers in the substrate (A) may be the same or different.
Combinations of fabrics and rovings of different densities can also be used. Among the substrates (A), the most general-purpose one is a substrate obtained by combining a glass fabric and a glass roving and bonding them.

The connection between the fiber fabric and the fiber roving may be a physical connection by a method of sewing the fabric by roving, but a bonding by an adhesive is more preferable. For example, a fiber roving to which a thermosetting resin is adhered may be used. There is a method in which a heat-cured adhesive is adhered to a fabric, or a roving to which a thermoplastic resin is adhered is adhered to a fiber fabric to be thermally fused.

Examples of the type of fiber fabric constituting the base material (A) (form), either cross, net or the like can be used. Among them, cloths and nets are selected because they can restrain the lateral deviation of the roving constituting the base material (A) and can be used continuously for a longer time .

In the present invention, after the base material (A) is continuously impregnated with the thermosetting resin, the base material (A) is squeezed so as to have a predetermined resin adhesion amount if necessary, and is heated in advance. It is drawn into a die and shaped and cured to produce an FRP molded product.
The material and structure of the die and the type of the impregnation bath used at this time are not particularly limited, and any of those conventionally used can be adopted.

In carrying out the pultrusion molding of the present invention, the base material (A) is preformed in accordance with the shape of the molded article to be obtained in a process before and after impregnating it with a thermosetting resin. It is preferable to draw in the die.

In the present invention, as the thermosetting resin for impregnating the base material (A), any known and commonly used thermosetting resin can be used. For example, unsaturated polyester resins, vinyl ester resins, epoxy resins, urea resins, phenol resins And an unsaturated polyester resin is particularly preferable. If necessary, a thermoplastic resin such as a polyvinyl chloride, a polypropylene resin, a polyethylene resin, a nylon resin or the like can be used in combination with the thermosetting resin.

The thermosetting resin may be used by filling it with a filler such as calcium carbonate, aluminum hydroxide, glass powder or the like, or may be added with various additives such as a silane coupling agent and a release agent. Agents may be used in combination. Further, coloring can be performed by adding a pigment.

The conditions for curing the substrate (A) impregnated with the thermosetting resin may be appropriately adjusted depending on the type of the resin, the presence or absence of the filler, and the thickness and shape of the molded article to be obtained. However, the curing conditions when using an unsaturated polyester resin are, for example, at 80 to 150 ° C. for 0.5 to 10 minutes.

In the present invention, not only the molding using only the substrate (A), but also the substrate (A) and the substrate other than the substrate (A) are superposed and then thermoset. It is also possible to adopt a method in which the resin is impregnated and then molded.

Specifically, the fiber base material (A) and a fiber mat having a higher density than the fiber fabric in the base material (A).
Preparative (B) and a combination of, the mat (B) as the center, at least piece outside the fiber base material (A), from superposed so as to be fiber fabric side surface, a thermosetting resin it , And then drawn into a pre-heated die and shaped and cured. By doing so, a molded article having a high density at the center in the cross-sectional shape can be obtained.

According to the present invention, a continuous molded product having a desired sectional shape can be obtained. The long molded product obtained in this manner is cut into a desired length as needed, and used for a desired application.

[0027]

EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

EXAMPLE 1 A continuous glass fiber cloth of 2300 g / km was arranged on one surface of a continuous glass fiber cloth having a width of 266 mm and 200 g / m ² so as to be parallel to the longitudinal direction of the cloth.
The 100 rovings were arranged so that the rovings were in close contact with each other, bonded with a thermosetting resin adhesive, wound up on a bobbin, and a continuous long composite glass fiber base material was obtained. FIG. 1 shows a cross-sectional view of this substrate. By the same operation, another long composite glass fiber substrate wound with the same bobbin was obtained.

A continuous glass fiber swirl mat having a width of 266 mm and a weight of 450 g / m ² was prepared, and the two composite glass fiber substrates obtained above were placed on both outer sides of the mat. Set on the conveying element of the pultrusion molding device so that the cloth side is superimposed on the surface, impregnated in the unsaturated polyester resin bath, squeezed it to the specified resin adhesion amount, preformed, and then unsaturated. The resin impregnated composite glass substrate is drawn into the die set to the curing temperature of the polyester resin, and shaped and heat-cured.
The apparatus was operated so that a series of steps were continuously performed to produce a continuous molded product. FIG. 2 shows a layer cross-sectional view of the obtained molded article, and FIG. 3 shows a shape cross-sectional view thereof.

The space required for preparing the glass fiber base material is to set a total of three bobbins: two bobbins for the composite glass fiber base material and one bobbin for the glass fiber swirl mat. The space required for placing the stand is only required, saving space.Also, the time and effort required to pass a large number of glass fiber rovings through the guide of the transfer device is eliminated. It was much shorter than that.

Further, it is possible to carry out the molding operation smoothly without involving the rovings together, there is almost no trouble at the time of molding, and it is possible to obtain a molded product having a very uniform glass content throughout the whole with high productivity. Was completed. Furthermore, when any of the base materials is consumed and lost during the molding operation, it is sufficient to connect a new base material every three bobbins in a short time. Did not drop much.

Comparative Example 1 A pultrusion apparatus provided with 600 roving conveyance guides (three per roving) was used, and a glass fiber cloth and a glass fiber roving (200) were used.
This is used without bonding with thermosetting resin adhesive,
A molded product was obtained in the same manner as in Example 1 except that a glass fiber swirl mat was used.

The space required for preparing the glass fiber base material is a total of 203 pieces, including 200 roving bobbins, two glass fiber cloth bobbins, and one glass fiber swirl mat bobbin. A space for setting the bobbin was required, and the space was extremely large as compared with the space in the first embodiment. A great deal of time had to be spent preparing a large number of glass fiber rovings through the guides of the conveyor.

Further, the rovings were entangled during the conveyance, and the forming operation could not be carried out smoothly, so that the drawing had to be carried out at a considerably slower speed than in the first embodiment. When trying to obtain a molded article at the same speed as in Example 1,
The rovings were not partially parallel to the longitudinal direction of the molded product, and a molded product having a uniform glass quality in all of the cross-sectional direction and the longitudinal direction could not be obtained. Furthermore, during the molding operation, when any material is consumed and lost, it is necessary to connect the material each time, and it takes a long time, and the productivity of the molded product has been extremely reduced. .

Example 2 The same operation as in Example 1 was carried out, except that only one continuous long composite glass fiber-based bobbin was used as it was.
A molded product was obtained.

The space required for preparing the glass fiber base material only needs to be the size of a stand for setting one bobbin for the composite glass fiber base material, and space can be saved. At the same time, the time and effort of passing a large number of glass fiber rovings, which have been indispensable in the past, through the guides of the transfer device can be omitted, and the preparation time of the device set for molding can be significantly reduced as compared with the conventional case.

In addition, it is possible to carry out the molding operation smoothly without involving the rovings, there is almost no trouble at the time of molding, and it is possible to obtain a molded product having a very uniform glass content throughout with high productivity with high productivity. Was completed. Furthermore, during the molding operation, when the substrate is consumed and lost,
One bobbin had only to be connected to a new substrate, which could be done in a short time, so that the productivity of the molded article was hardly reduced.

[0038]

According to the present invention, since a specific composite fiber base material is used, it is possible to solve many drawbacks which have been an important problem in the conventional pultrusion molding method. That is,
The preparation time for setting the bing in the drawing machine can be shortened, and the number of roving bobbins to be used can be reduced, so that the roving space can be reduced, reducing troubles during molding, simplifying maintenance, and improving the quality of FRP molded products. And so on, and can be expected to greatly contribute to the improvement of the pultrusion molding technology.

[Brief description of the drawings]

FIG. 1 is a sectional view of a substrate used in Example 1.

FIG. 2 is a cross-sectional view of a layered structure of a molded product obtained in Example 1.

FIG. 3 is a cross-sectional view related to the shape of a molded product obtained in Example 1.

[Explanation of symbols]

 1, 1 ', 1 "glass fiber roving 2, 2', 2" glass fiber cloth 3 glass fiber swirl mat

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B29C 70/00-70/88

Claims (2)

(57) [Claims] 1. A long fiber selected from a cloth and a net obtained by bonding a plurality of fiber rovings 1 aligned at least on one surface of a fabric 2 so as to be parallel to the long direction. A method for producing a fiber-reinforced plastic molded article , comprising impregnating a composite fiber base material (A) with a thermosetting resin , drawing it into a heated die, and continuously shaping and thermosetting. . 2. A long fiber selected from a cloth and a net.
At least one side of the fabric 2 is flat
Combine multiple fiber rovings 1 aligned to form a row
Composite fiber base material obtained by the (A), <br/> substrate comprising a fiber mat (B) was centered, the at least single outside the fiber base material (A), the fiber fabric side surface from superposed as it was impregnated with a thermosetting resin, it
It is drawn into a heated die and continuously shaped and heat-hardened.
Fiber-reinforced plastic molded product characterized by
Manufacturing method.