JPH1177709A - Fiber reinforced resin unit plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make molding possible under low pressure press molding conditions by making a core material structure which is not deformed even when decomposition gas is generated in a rigid expanded plastic material by high temperatures. SOLUTION: A fiber reinforced resin unit plate 1 is formed by a method in which a thermosetting resin is applied on the surface of an expanded plastic material and cured or reinforcing fibers impregnated with the thermosetting resin are laminated on the surface, and the resin is cured and made to be of core material structure 3 which is not deformed even when decomposition gas is generated in the plastic material by high temperatures. An SMC which wraps it is made to be a low viscosity SMC 2 containing at least propylene glycol and dipropylene glycol as the glycol component of an unsaturated polyester resin which is a base resin, and it is press-molded with the use of the core material 3 and the SMC 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a unit plate made of fiber reinforced resin, and more particularly to a unit plate made of fiber reinforced resin having both improved heat insulation and light weight.

[0002]

2. Description of the Related Art Conventionally, there has been known a fiber reinforced resin unit plate enclosing a hard foamed plastic material in which a urethane resin, a phenol resin, or an unsaturated polyester resin is foamed in advance by a fiber reinforced resin layer. Hand lay-up molding method, spray-up molding method, resin transfer molding method or matched die molding method that can be performed under low-temperature and low-pressure conditions so as not to cause decomposition or deformation of the hard foamed plastic material and fiber reinforced resin layer at the time of And the like are known. However, when fabricating a fiber-reinforced resin unit plate using each of these conventional molding methods, there are disadvantages such as a poor working environment and low productivity.

As an alternative to solve the above-mentioned problem, it is recalled that a conventional general SMC is press-formed under high-temperature and high-pressure press forming conditions as the fiber-reinforced resin layer. Table 1 shows the basic composition of the general SMC.

[Table 1]

[0004]

In Table 1, the SMC
Is based on 100 parts by weight of a resin component consisting of 80 parts by weight of an unsaturated polyester resin and 20 parts by weight of a polystyrene resin (low shrinkage resin), and 1 part by weight of t-
129 consisting of butylperoxybenzoate (hardener), 5 parts by weight of zinc stearate (internal release agent), 120 parts by weight of calcium carbonate (filler) and 3 parts by weight of pigment
209 parts by weight of the resin compound is obtained by blending parts by weight of other components. 70% by weight of this resin compound is used as a reinforcing material for roving glass chop fiber 3
What is impregnated at 0 weight percent is the commonly used SMC formulation.

In the above conventional SMC, dipropylene glycol is not contained in the glycol component contained in 80 parts by weight of the unsaturated polyester resin in the basic formulation, and the viscosity is 5 × 10 ⁵ to 10 ×. was 10 ⁵ poise.

However, such a conventional SMC allows a laminated product containing a hard foamed plastic material which has been foamed in advance at 130 ° C. to 150 ° C. and about 50 kg / cm.
Press molding under the high temperature and high pressure press molding conditions of ² ,
a) Decomposition gas is generated in the rigid foamed plastic material due to too high temperature and swelling or other convex deformation is generated in the molded product. b) Deformation or crushing of the rigid foamed plastic material due to too high pressure. And c) due to high viscosity, poor filling may occur.
For this reason, conventionally, there was a problem that SMC as shown in Table 1 above could not be used as it was as a fiber reinforced resin layer to be applied to the hard foamed plastic material, that is, press molding could not be performed.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and the gist of the present invention is as follows. Second, by using SMC that can be molded under low-pressure press molding conditions with a core material structure, it is made of fiber reinforced resin molded using two measures to prevent deformation and crushing of the rigid foamed plastic material. It is on the unit plate.

That is, according to the first aspect of the present invention, the core material is obtained by applying and curing a thermosetting resin on the surface of a hard foamed plastic material, or impregnating the surface of the hard foamed plastic material with a thermosetting resin. Any one of laminated and cured reinforcing fibers, the SMC containing at least propylene glycol and dipropylene glycol as glycol components of the unsaturated polyester resin as the base resin, and at least one surface of the core material The SMC
An object of the present invention is to provide a fiber-reinforced resin unit plate, which is formed by integrally heating and pressing a product in a mold cavity.

According to a second aspect of the present invention, there is provided an unsaturated polyester resin according to the first aspect, wherein the proportion of propylene glycol to dipropylene glycol, which is contained at least as a glycol component, is 35 to 45 mol% to 65 to 55 mol%. The present invention also provides a fiber-reinforced resin unit plate using SMC.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, Table 1 and Table 2 described later
The present invention will be described in detail with reference to FIGS. Table 1 is a basic composition table of SMC, and Table 2 is a summary of Examples and Comparative Examples. FIG. 1 is a cross-sectional view showing an embodiment of a laminate of a core material and SMC in the present invention, FIG. 2 is a perspective view of one embodiment of a fiber-reinforced resin unit plate formed in the same manner, and FIG. FIG. 3 is a sectional view taken along line AA of FIG. 2.

Referring to FIG. 1, the structure of a laminate of the core material and the SMC before molding in the present invention will be described. In FIG. 1, reference numeral 1 denotes a laminate, and the laminate 1 is a laminate in which a core material 3 and a semi-cured SMC 2 are laminated. The core material 3 includes an inner layer 32 made of a hard foamed plastic material and a hardened outer layer 31 covering the surface of the inner layer 32.

The hard foamed plastic material of the inner layer 32 of the core material 3 is formed by foaming any one of urethane resin, phenol resin and unsaturated polyester resin in advance.

The outer layer 31 of the core 3 has two embodiments. As a first type of outer layer 31, after applying a thermosetting resin of any one of urethane resin, phenol resin and unsaturated polyester resin to a thickness of about 1 mm on the surface of an inner layer 32 made of a hard foamed plastic material, It is cured by irradiation and heating.

As a second kind of outer layer 31, a reinforcing fiber is impregnated with a thermosetting resin of urethane resin, phenol resin or unsaturated polyester resin on the surface of an inner layer 32 made of a hard foamed plastic material. The laminated FRP having a thickness of about 1 mm is pressed, heated and cured.

A semi-cured SMC 2 is laminated on both sides of the core material 3. However, the SMC does not necessarily have to be laminated on both sides of the core material, and may be one in which only one surface of the core material is laminated. The formulation of SMC2 used in the present invention is the same as the basic formulation in Table 1 already described in the description of the prior art. However, the feature of the SMC2 used in the present invention is that it contains at least propylene glycol and dipropylene glycol as a glycol component in the unsaturated polyester resin which is the base resin of the SMC2. And the component ratio of dipropylene glycol to 35 to 45 mol% to 65 to 55 mol%. The viscosity of SMC2 used in the present invention is 5 × 10 ^{4 to} 5 × 1.
0 is ⁵ poise, the viscosity is lower than that of the general SMC used the conventional.

Here, an embodiment of a fiber-reinforced resin unit plate obtained by press molding will be described in advance. As shown in FIGS. 2 and 3, the fiber-reinforced resin unit plate 4 has a flat portion 5b of about 1 meter square and a flange 6 having a height of about 5 cm on four sides. The lower side of the foam layer 5c is surrounded by the hardened SMC layer 5a, and the upper side of the foam layer 5c is further surrounded by the hardened SMC layer 5b.

Hereinafter, Examples and Comparative Examples will be described based on Table 2.

[0018]

[Table 2]

<Example 1> The core material was obtained by applying and curing an urethane foam plate for the inner layer and an unsaturated polyester resin for the outer layer. Next, semi-cured S according to the basic formulation
MC was obtained. However, the unsaturated polyester resin, which is the base resin in this SMC, is
The one containing at least propylene glycol and dipropylene glycol and having a component ratio of the propylene glycol to dipropylene glycol of 35 mol% to 65 mol% was used. Next, a fiber mat of continuous strand is arranged in the mold cavity for unit plate molding,
The S was cut into a predetermined size and weighed on the mat.
The MC and the core material were placed on top of each other such that the core material was sandwiched therebetween. Further, the heating conditions for molding were as follows: the upper mold temperature was 145 ° C., the lower mold temperature was 135 ° C., the pressurizing condition was 25 kg / cm ² , and the pressurizing holding time was 5 minutes.

When the fiber-reinforced resin unit plate thus obtained was evaluated, the core material was good without any deformation or destruction such as swelling or crushing, and a desired unit plate could be obtained. Good evaluation is indicated by a circle in Table 2 (the same applies hereinafter). The reason for this is that the outer layer of the core material suppresses the swelling deformation of the urethane foam plate due to high temperature, and the viscosity of the modified SMC used is as low as 5 × 10 ^{4 to} 5 × 10 ⁵ poise. This is considered to be because a pressure as low as / cm ² became possible, and this low pressure prevented crushing deformation or destruction of the urethane foam plate. In this viscosity range, no stickiness remains on the SMC surface,
In addition, the SMC protective film has good releasability,
There is an advantage that the handling characteristics of the MC are improved.

<Example 2>: The only difference from Example 1 was that an outer layer of the core material was obtained by laminating and curing an unsaturated polyester resin FRP, and the others were different from Example 1. The same is true. And the evaluation result was the same as that of Example 1. Therefore, detailed description has been omitted.

<Example 3> The difference from Example 1 is that the unsaturated polyester resin, which is the base resin in the resin compound, contains at least propylene glycol and dipropylene glycol as its glycol components. Example 2 is the same as Example 1 except that the component ratio of glycol to dipropylene glycol was 45 mol% to 55 mol%. And the evaluation result was the same as that of Example 1. Therefore, detailed description has been omitted.

<Example 4> A difference from Example 1 is that first, the outer layer of the core material is made of FRP of unsaturated polyester resin.
Second, the unsaturated polyester resin as the base resin in the resin compound contains at least propylene glycol and dipropylene glycol as its glycol components, and the propylene glycol Example 2 is the same as Example 1 except that a component having a component ratio of 45 mol% to 55 mol% of dipropylene glycol was used. And the evaluation result was the same as that of Example 1. Therefore, detailed description has been omitted.

<Comparative Example 1>: As the core material, there is an inner urethane foam plate as compared with each of the examples, but no outer layer is formed. Next, a semi-cured SMC was obtained according to the basic compounding recipe. However, this SMC does not contain a dipropylene glycol component as a glycol component of a conventional specification product, that is, an unsaturated polyester resin as a base resin. Next, a continuous strand fiber mat is placed in the mold cavity for unit plate molding, cut into a predetermined size on the mat, and weighed, the conventional SMC and the urethane foam board are weighed with the foam board. Were placed on top of each other so as to be sandwiched. Furthermore, the heating conditions for the molding were as follows: the upper mold temperature was 145 ° C, and the lower mold temperature was 1
The temperature was 35 ° C., the pressure was 25 kg / cm ² , and the pressure holding time was 5 minutes.

The fiber-reinforced resin unit plate thus obtained was evaluated. 1) Decomposition gas was generated in the urethane foam plate due to high temperature. As a result, the urethane foam plate was swelled and deformed. 2) The SMC of the conventional specification has a viscosity of 5 × 1
Since the flow rate was as high as 0 ⁵ to 10 × 10 ⁵ poise, the fluidity was poor, and poor filling occurred, which was not good. For 1) and 2), a desired unit plate could not be obtained. Poor evaluation is indicated by a mark x in Table 2 (the same applies hereinafter).

<Comparative Example 2>: The only difference from Comparative Example 1 is that the pressurizing condition was 50 kg / cm ^2, and the other points were the same as Comparative Example 1. As a result of the evaluation, defects 1) and 2) occurred in Comparative Example 1, but in addition, the urethane foam plate was crushed by high pressure and failure of fracture occurred, and a desired unit plate could not be obtained. .

In each of the above examples, a urethane foam plate was used as the hard foamed plastic material used for the inner layer of the core material, and an unsaturated polyester resin was used as the thermosetting resin constituting the outer layer of the core material. The hard foamed plastic material is not limited to this, and may be either a phenolic resin or an unsaturated polyester resin. The thermosetting resin that is a component of the outer layer of the core material may be urethane. Either resin or phenol resin may be used.

[0028]

As described above, in the present invention, the core material is
Apply thermosetting resin to the surface of hard foam plastic material,
The cured resin or the hard foamed plastic material is laminated or cured with a reinforcing fiber impregnated with a thermosetting resin on the surface, and the SMC is made of at least propylene as the glycol component of the unsaturated polyester resin as the base resin. A fiber-reinforced resin, wherein the core material contains glycol and dipropylene glycol and the SMC is superimposed on at least one surface of the core material, and heated and pressed in a mold cavity and integrally molded. By providing a unit plate and a fiber reinforced resin unit plate in which the component ratio of propylene glycol to dipropylene glycol is 35 to 45 mol% to 65 to 55 mol%, A core material structure that does not deform even if decomposition gas is generated in the rigid foam plastic material,
Secondly, since low viscosity SMC can be adopted, molding can be performed under low pressure press molding conditions, so press molding under low pressure conditions is possible, and the work environment is good, productivity is high, and there is no deformation and filling is performed. It is possible to obtain a fiber-reinforced resin unit plate having no defect.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a laminate of a core material and SMC in the present invention.

FIG. 2 is a perspective view showing one embodiment of a fiber-reinforced resin unit plate of the present invention.

FIG. 3 is a sectional view taken along the line AA of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Laminate 2 SMC 3 Core material 31 Outer layer 32 Inner layer 4 Unit plate made of fiber reinforced resin 5a SMC layer 5b SMC layer 5c Foam layer

Claims (2)

[Claims] A core material obtained by applying and curing a thermosetting resin on the surface of a hard foamed plastic material or laminating and curing reinforcing fibers impregnated with a thermosetting resin on the surface of a hard foamed plastic material. And the SMC is
The unsaturated polyester resin which is the base resin contains at least propylene glycol and dipropylene glycol as glycol components, and the core material having at least one surface thereof overlaid with the SMC is heated and heated in a mold cavity. A unit plate made of fiber reinforced resin, which is integrally molded by pressing. 2. The fiber-reinforced resin unit plate according to claim 1, wherein the component ratio of propylene glycol to dipropylene glycol is 35 to 45 mol% to 65 to 55 mol%.