JPS6356437A - Preparation of fiber reinforced synthetic resin molded article - Google Patents

Abstract

PURPOSE:To obtain a fiber reinforced synthetic resin molded article excellent in strength and a heat insulating property, by forming a fiber reinforced synthetic resin outer layer by spraying a foamable synthetic resin and a reinforcing fiber to the surface and peripheral part of a reinforcing body. CONSTITUTION:A reinforcing body 5 is pressed at such a stage that a foamable synthetic resin layer 3 for forming an inner layer 4 is not almost foamed. The foamable synthetic resin layer is foamed and cured in a pressed state to form the fiber reinforced synthetic resin inner layer 4, and the reinforcing body 5, the fiber reinforced synthetic resin inner layer 4 and a main body 2 are integrally fixed. Next, a foamable synthetic resin and a reinforcing fiber are sprayed to at least the surface and peripheral part 7 of the reinforcing body 5 to form a fiber reinforced foamable synthetic resin layer 8 which is, in turn, foamed and cured to form a fiber reinforced synthetic resin outer layer 9.

Description

Detailed Description of the Invention (Industrial Application Field) Regarding the method for producing the Fi fiber reinforced synthetic resin molded product of the present invention,
In particular, it relates to fiber-reinforced synthetic resin molded products such as bathtubs, containers, and septic tanks that have strong strength and insulation properties.

(Prior art) Conventionally, there are press molding, hand lay-up molding, spray-up molding, and other molding methods for am-reinforced synthetic resin (hereinafter abbreviated as rFRPJ). , septic tanks, etc. are molded, but such molded products that receive a large load on the bottom of the molded product are, for example, when molding a stepped bathtub as shown in FIG. 1 by the spray-up molding method, as shown in FIG. and as shown in Figure 5,
A gel coat layer 1' is formed on mold M', and glass fiber and unsaturated polyester resin are sprayed onto the gel coat layer 1' to form a main body 2' made of M-fiber reinforced synthetic resin. In the example shown in Fig. @1, the reinforcing body 5' made of a plate-shaped body is attached to the part K of the FiF, for example, but in order to do so, a through hole 10' with a diameter of 5 to 10% is made in the reinforcing body in advance.
% pitch, and press it onto the newly sprayed synthetic resin 3', and further form a synthetic resin layer 8' again, so that the reinforcing body DA is sandwiched between the synthetic resin layers 3' and 8'. Instead, it is attached to the main body 2' by hardening the integral part.

(Problems with the prior art) However, in the conventional method described above, since the main body is formed of FRP, the surface opposite to the surface in contact with the gel coat layer 1' is normally In many cases, the surface is not flat, and even if the synthetic resin layer 3' formed thereon is applied to a substantially uniform thickness, many cavities 6' are formed between it and the lower surface of the reinforcing body 5'. . On the other hand, even if it is formed flat,
As shown in FIG. 5, if a reinforcing lip 11' is formed on the surface of the main body 2', the formation of a cavity 6' is unavoidable, and the cavity The reinforcing effect of the reinforcing body 5' is reduced, and when an external force is applied to the hollow portion, it becomes lumpy, which is a big disadvantage in terms of quality.

(Means for Solving the Problems) The purpose of the present invention to solve the above problems is that when manufacturing a fiber-reinforced synthetic resin molded product, after molding a fiber-reinforced synthetic resin body, Spray foamable synthetic resin and reinforcing fibers on the surface to form a fiber-reinforced synthetic resin inner layer,
Pressing and attaching a reinforcing body onto the fiber-reinforced synthetic resin inner layer,
A method for manufacturing a fiber-reinforced synthetic resin molded article, comprising spraying a foamable synthetic resin and reinforcing fibers onto at least the surface of a reinforcing body and the surrounding area of the reinforcing body to form a fiber-reinforced synthetic resin outer layer. Exists.

The reinforcing body in the present invention is a plate-shaped, lattice-shaped, or rod-shaped one that takes into account the shape of the part of the main body to be reinforced and the degree of reinforcement, and the material thereof can be wood, plywood, or particle board. , iron, aluminum, and other suitable materials can be selected and used.

When a plate-like structure is used, it is preferable to have nine through holes in the plate surface so that the inner and outer layers of the fiber-reinforced synthetic resin can exert an anchoring effect when attached to the main body.

Also, the parts of the main body that should be reinforced are not necessarily the parts where the load is the greatest.

As the foamable synthetic resin in the present invention, a synthetic resin that has excellent adhesion to the synthetic resin forming the main body and a synthetic resin mixed with commonly used additives such as a foaming agent are used. Foams that are often formed include polyester resin foams, polyurethane resin foams, etc., and those that form so-called rigid foams are used.

Examples of reinforcing tal in the present invention include inorganic or organic fibers such as glass fibers, vinylon fibers, and Tetron fibers, and the fiber length is preferably about 10% to 35%, but less than 10%. If the reinforcing effect is insufficient,
If it exceeds 35%, the movement of fibers tends not to follow the movement of resin during foaming.

The mixing ratio of the foamable synthetic resin and the reinforcing fibers in the present invention cannot be determined unconditionally depending on the type and length of the synthetic resin and the fibers, but it is usually 100 parts by weight of the synthetic resin to 1 part of the fibers.
The amount is preferably about 0 to 60 parts by weight.

In the present invention, as a method of spraying foamable synthetic resin and reinforcing fibers onto the surface of the main body to form a fiber-reinforced synthetic resin inner layer or outer layer, a known apparatus used for spray-up molding can be used as is. As the resin is ejected from the nozzle at a predetermined pressure, the fibers cut near the nozzle are scattered by the rush of the ejected resin or by the flow of pressurized gas prepared separately. Adjustment and movement of the nozzle distance may be performed manually, mechanically, or by an industrial robot. Further, all of this operation may be performed in a vacuum chamber.

In the invention 1c, the fiber-reinforced synthetic resin inner layer is provided at a predetermined location for attaching the reinforcing body, as shown in FIG.
b) As shown in K, the reinforcing body 5 is pressed when the foamable synthetic resin R3 for forming the inner layer 4 is substantially unfoamed. The means for suppressing may be a suitable weight, or a mechanical force such as a hydraulic cylinder may be used. In this suppressed state, the foamable synthetic resin layer 3 is foamed and hardened. The reinforcing synthetic resin inner layer 4 is made up of a reinforcing body 5 and a fiber-reinforced composite, as shown in Figure (b). , the resin inner layer 4 and the main body 2 are integrally fixed. The foaming is free foaming, and the secondary foaming is allowed to protrude around the reinforcing body 5 or over the through hole 10 of the reinforcing body 5 as shown in FIG. 2 (4) K. It should be noted that there is no problem even if the foamable synthetic resin layer 3Fi and the reinforcing body 5 start foaming before or after the start of pressing.

Next, at least the surface of the reinforcing body 50 and the peripheral part 7 of the reinforcing body 5 are sprayed with a foamable synthetic resin and reinforcing fibers to form a fiber-reinforced foamable synthetic resin layer 8, and the layer 8 is foamed and hardened. The fiber-reinforced synthetic resin outer layer 9 may be formed using the following steps.

(Function) When the surface of the main body to which the reinforcing body is attached is not flat, or when a surface reinforcing lip is formed on the main body 2, the gap between the lower surface of the reinforcing body 5 and the surface of the main body 2 The foamable synthetic resin layer 3 foams and fills the cavity 6 formed in the cavity 6 .

(Example) First, the spray-up molding method is used, and the bathtub molding process is as shown in Figure 1! Gel coat layer 1 (see Figure 2) is formed on the MM, and then unsaturated polyester resin and glass fiber are sprayed to form a layer made of fiber-reinforced synthetic resin. Thereafter, it was completely cured and a main body 2 made of fiber-reinforced synthetic resin was molded.

Next, with the main body 2 attached to the mold MK, the spray-up device used for molding the main body 2, that is, a spray nozzle, a resin liquid pressure feeding device, a cutter, a roving feeding device, etc., is sprayed. This method uses a device (none of which is shown) that has exactly the same function as the device, as well as a group of devices such as an industrial robot, an overhead crane, and a control panel for mechanically operating this process. A foamable synthetic resin layer 3 is formed by spraying a mixed liquid mainly consisting of a foaming agent and glass fibers whose cutting length is adjusted to 32% on the surface of the deepest part F of the bathtub, and then a foamable synthetic resin layer 3 is formed on the layer 3. It is made of plywood and has a large number of through holes 10 with a diameter of 5 to 10% at a pitch of 200 to 300%. The reinforcing body 5 thus provided was pressed and attached using a presser (not shown) using an air cylinder. The initial state at this time is shown in FIG.
Similar irregularities were formed on the surface of the foamed synthetic resin layer 30, and many cavities 6 were formed between the surface of the foamable synthetic resin layer 30 and the lower surface of the reinforcing body 5. As shown in the figure, the inside of the fiber-reinforced foamed synthetic resin is @4, and the cavity is #6.
-iThe inner layer 4 resulted in a completely filled structure. Next, on the surface of the reinforcing body 50 and the peripheral part 7 of the reinforcing body 5,
A foamable synthetic resin layer 8 was formed using the same materials and equipment as in the case of forming the fiber-reinforced foamed synthetic resin inner layer 4, and the layer 8 was foamed and cured to form a wIt fiber-reinforced π-pond synthetic resin outer layer 9. . In this way, the outer layer 9 and the inner layer 4 are completely bonded and integrated at the through hole 10 of the reinforcing body 5 and the periphery of the reinforcing body 5, and one reinforcing body 5 is fixed to the main body 2. During this period, the time required from the formation of the inner layer 4 to the formation of the outer layer 9 is on average 6 to 10 minutes.

(Comparative example) The inner and outer layers are formed using non-foaming fiber-reinforced synthetic resin,
A bathtub was molded in the same manner as in the example except that the reinforcing body had a pitch of through holes of 50% to 100%. The average time required from forming the inner layer to forming the outer layer is 1 hour to 2 hours, and there are many cavities between the main body and the reinforcing body, and the strength of the attachment of the reinforcing body to the main body is insufficient. Met.

(Effects) The method for producing a fiber-reinforced synthetic resin molded article of the present invention includes molding a fiber-reinforced synthetic resin main body, and then spraying a foamable synthetic resin and reinforcing fibers onto the surface of the main body to form a fiber-reinforced synthetic resin inner layer. At the same time, the reinforcing body is attached by pressing it onto the inner layer, so even if the surface of the main body is not flat or there is a reinforcing lip protruding from the surface of the main body, the reinforcing body can be attached easily. The cavity formed between the inner layer and the main body is filled with the synthetic resin and fibers foamed during the foaming process of the inner layer, and if the reinforcing body has through holes etc., the anchoring effect will increase, and the reinforcing body Since it is firmly attached to the main body and the thickness of the reinforcing portion is increased, the quality is improved and the main body is also provided with a heat insulating effect. Also, compared to using non-foamed synthetic resin,
The short curing time reduces mold residence time in the manufacturing process, improving productivity.

[Brief explanation of drawings]

Figure 1 is a front cross-sectional view showing an embodiment of the manufacturing method of the present invention, and Figure 2 is an enlarged cross-sectional view of the main part showing the process in the manufacturing method of the present invention. Figures 4 and 5 show the state immediately after forming the resin inner layer; @) shows the state in which the fiber-reinforced synthetic resin inner layer has been foamed and hardened; Figures 4 and 5 show the conventional example, corresponding to Figure 2 (A). FIG. 4 shows a case where the surface of the main body is uneven, and FIG. 5 shows a case where there is a reinforcing lip on the surface of the main body. 1 Nigel coat layer, 2: main body, 3: foamable synthetic resin layer,
4: Fiber-reinforced synthetic resin inner layer, 5: Reinforcement body, 6: Cavity, 7
: Peripheral part of reinforcing body 5, 8: Foaming synthetic resin layer, 9: &l
Illization synthetic resin outer layer, 10: Through hole, M: Mold procedure? City Official Book (Method)” November 27, 1986

Claims (1)

[Claims] 1. When manufacturing a fiber-reinforced synthetic resin molded product, after molding a fiber-reinforced synthetic resin main body, foamable synthetic resin and reinforcing fibers are sprayed onto the surface of the main body to form a fiber-reinforced synthetic resin inner layer, A reinforcing body is pressed and attached onto the fiber-reinforced synthetic resin inner layer, and a foamable synthetic resin and reinforcing fibers are sprayed on at least the surface of the reinforcing body and the surrounding area of the reinforcing body to form a fiber-reinforced synthetic resin outer layer. A method for producing a fiber-reinforced synthetic resin molded article.