JPH077246A - Manufacture of in-molded product containing electronic component constituting material - Google Patents

Abstract

PURPOSE:To scarcely cause a surface void, an inner void and damage of an electronic component when an in-molded product containing an electronic component constituting material is manufactured by altering mixture of thermosetting resin, to obtain an excellent in-molded product and to further relatively simply prevent occurrence of such malfunction without necessity of many experiments. CONSTITUTION:A method for manufacturing an in-molded product containing an electronic component constituting material has the steps of laminating fiber- reinforced resin prepregs 4 on peripheries of electronic component constituting materials 2, 3, heating them and pressuring them, and comprises the step of regulating the quantity of resin which flows out from the prepregs while pressurizing to 3-35wt.% of a ratio (resin flow rate) of the quantity of the resin to the weight of the prepreg before pressurizing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an in-molded product with a built-in electronic component structure, and more particularly, to combine electronic components such as ICs and to provide one or more functions such as oscillation, reception, calculation and storage. The present invention relates to a manufacturing method suitable for use in the manufacture of an in-mold product with a built-in electronic component structure, which is obtained by in-molding (embedding) a developed structure (hereinafter referred to as an electronic component structure) in a long fiber reinforced resin.

[0002]

2. Description of the Related Art As a method for fixing electronic parts such as ICs in electric / electronic devices, bolts are used for nuts in bosses which are preformed on the inner surface of the housing of a device of a printed wiring board on which ICs are mounted. Fixing method (hereinafter referred to as bolt fixing method), a method of adhering the IC module to the inner surface of the housing of the device with an adhesive (hereinafter referred to as adhesive fixing method), forming a recess in the inner surface of the device housing in advance,
A method in which an IC module coated with an adhesive is mounted in the recess and heat-welded (hereinafter referred to as heat-welding fixing method) is used. As the housing material of the above-mentioned equipment, resins such as ABS resin and vinyl chloride resin, and glass fiber reinforced resin (F
RP) is commonly used.

However, the above fixing method has the following problems. That is, in the bolt fixing method, at least a space necessary for fixing the printed wiring board needs to be provided between the board and the housing, so that it is difficult to make the device compact. On the other hand, in the adhesive fixing method and the heat-welding fixing method, it is easy to make the device compact because the space required for fixing is small, but when the housing bends
Due to the difference in elastic modulus between parts such as IC and the housing material, stress acts in the vicinity of the fixed part (adhesive part or heat-welded part), and there is a problem that peeling of parts and cutting of IC lead wires are likely to occur. . Furthermore, in any of the above fixing methods, it is necessary to coat the module surface with a sealing resin in order to protect the IC and the IC lead wires from moisture such as moisture, corrosive gas, chemicals and the like. Further, at least the housing molding process and the mounting substrate fixing process are required, and the number of manufacturing processes is large.

Therefore, studies have been made to solve the above problems, and as a result, an electronic component component-containing in-mold product in which the electronic component component is integrally molded in a long fiber reinforced resin layer and incorporated therein. Has been proposed (Japanese Patent Application No. 3-
No. 345181). Such an in-molded product is obtained by laminating fiber-reinforced resin prepregs obtained by impregnating reinforced long fibers with a thermosetting resin on both sides or one side (around) of an electronic component composition, and heating with a heated mold. It is manufactured by a method of pressing with a mold (compression molding). At this time, the fiber reinforced resin prepreg is compressed and hardened while incorporating the electronic component component into a long fiber reinforced resin layer. This long fiber reinforced resin layer contains reinforced long fibers and resin.

FIG. 1 shows an example of the manufacturing situation of the in-molded product, and FIG. 2 shows an example of the in-molded product. In FIGS. 1 and 2, reference numeral 2 denotes a printed wiring board, 3 denotes an electronic component such as an IC mounted on the substrate 2, and these two components constitute an electronic component structure. 2 and 4 are long fiber reinforced resin prepregs, 5 is an upper mold, 6 is a lower mold, and 1 is a long fiber reinforced resin layer.

According to the in-mold product with a built-in electronic component structure, the housing can be made small so that the device can be easily made compact. Moreover, since the device is hard to bend and has excellent strength, it is possible to peel off the component and prevent the IC lead wire from being peeled off. Cutting is unlikely to occur, and since the electronic component component can be manufactured by in-molding it in the long fiber reinforced resin layer and integrally molding it into a housing shape, the manufacturing process is basically greatly reduced.

[0007]

However, in the conventional method for manufacturing an in-molded electronic component component, the above method is optimal when the composition of the thermosetting resin (molding material) is changed according to various requirements. There is a problem that it is necessary to search for such in-mold integral molding conditions each time.

In other words, there are various requirements for in-mold products with built-in electronic component components, and these requirements are often met by blending a thermosetting resin (molding material) to satisfy these requirements. However, in such a case, by simply changing the composition of the thermosetting resin, the occurrence of surface voids or the like of the molded product (in-mold product) changes every time the composition is changed, causing a problem that the surface quality deteriorates, The difficulty of destroying the built-in electronic components may change, resulting in damage to the electronic components. Therefore, in order to prevent such a problem, each time the composition of the thermosetting resin is changed, optimum in-mold integral molding conditions for the compounded resin may be applied. It is necessary to conduct a large number of experiments by using molding conditions (heating temperature in the mold, pressurizing speed, pressure, etc.) as parameters, and to search for optimum molding conditions. Therefore, the search requires a lot of time and materials. In addition, there is a problem that a large amount of experimental molding cost is required.

The present invention has been made by paying attention to such a situation, and an object thereof is to solve the problems of the above-mentioned prior art and to change the composition of the thermosetting resin to build the electronic component constituent. When manufacturing an in-molded product, it is difficult for the occurrence of defects such as deterioration of surface quality and destruction of electronic parts due to the occurrence of surface voids, and an in-molded product with a built-in electronic component composition that does not have such a problem is obtained, and An object of the present invention is to provide a method for manufacturing an in-mold product with a built-in electronic component structure, in which the occurrence of defects can be relatively easily achieved without requiring a large number of experiments as in the case of the conventional technique. .

[0010]

In order to achieve the above object, the method of manufacturing an in-molded electronic component component-embedded product according to the present invention has the following configuration. That is, in the manufacturing method according to claim 1, an electronic component structure in which a fiber-reinforced resin prepreg in which thermosetting resin is impregnated into reinforcing long fibers is laminated on one side or both sides of the electronic component structure, and then heated and pressed. In the method for manufacturing a product-embedded in-molded product, the weight of the resin flowing out of the prepreg during the pressing is ratio of the weight of the resin to the prepreg weight before pressing (hereinafter,
The resin flow rate) is adjusted to 3 to 35 wt%, which is a method for manufacturing an in-mold product with a built-in electronic component component.

According to a second aspect of the present invention, the resin weight flowing out of the prepreg is adjusted by adjusting the fluidity of the resin in the prepreg. It is a manufacturing method.
The manufacturing method according to claim 3, wherein the weight of the resin flowing out from the prepreg is adjusted by preheating the prepreg before the heating and pressing to adjust the fluidity of the resin in the prepreg. It is a method of manufacturing an in-mold product with a built-in component composition.

[0012]

As described above, in the method for manufacturing an in-mold product with a built-in electronic component structure according to the present invention, the weight of the resin flowing out from the prepreg during the pressurization after laminating the fiber reinforced resin prepreg is 3 to 35 wt at a resin flow rate. %, So even if the thermosetting resin composition is changed due to this adjustment of the resin flow rate, problems such as surface voids, internal voids, and destruction of electronic parts will occur. Is less likely to occur,
An in-mold product with a built-in electronic component structure that does not have such a problem can be obtained, and the occurrence of such a problem can be relatively easily achieved without requiring many experiments.

That is, an experiment for manufacturing an in-molded electronic component component was conducted under various conditions. As a result, when the resin flow rate during pressurization after prepreg lamination was adjusted to 3 to 35 wt%, thermosetting It is possible to produce good in-mold products with built-in electronic component components without the occurrence of surface voids, internal voids, and destruction of electronic parts, regardless of the composition of the resin. It was The present invention has been completed based on such findings, and therefore, according to the present invention, even when the composition of the thermosetting resin is changed, the occurrence of surface voids, the generation of internal voids, the destruction of electronic parts, etc. It is possible to obtain an in-mold product with a built-in electronic component component that is less likely to cause a problem and does not have such a problem.

Since the resin flow rate can be easily adjusted, it can be realized by changing the conditions such as the pressurizing temperature when manufacturing the in-molded product. Alternatively, conditions such as pressurizing temperature at which the resin flow rate is 3 to 35 wt% are obtained by a simple preliminary experiment before manufacturing the in-molded product,
It can be realized by applying the conditions when manufacturing the in-molded product. Therefore, without requiring a large number of experiments, the resin flow rate can be adjusted and the occurrence of the problem can be prevented relatively easily.

In the method for producing an in-mold product according to the present invention, the resin flow rate adjusted as described above is 3 to 35 wt%.
If less than 3 wt%, surface voids and electronic parts may be destroyed by blending thermosetting resin, and if it exceeds 35 wt%, internal voids may be produced by blending thermosetting resin. Because there is.

The reason why problems tend to occur when the resin flow rate is as low as less than 3 wt% or as high as more than 35 wt% will be described below. When the resin flow rate is low, that is, when the fluidity of the molten resin is low, the resin does not flow to the surface of the molded product and a void is generated on the surface. Further, when the fluidity of the molten resin is low as described above, the molten resin cannot flow around the electronic component, and the pressure is applied only in the direction in which the pressure is applied, the stress of the component is concentrated, and the electronic component is concentrated. Parts may be destroyed. On the other hand, when the resin flow rate is high, that is, when the fluidity of the molten resin is high, the pressure applied to the molten resin portion does not increase, so that bubbles do not escape from the clearance between the cavity mold and the core mold to the outside of the mold, and voids are formed. It remains inside. Alternatively, it is also considered that the pressure applied to the molten resin portion does not increase, so that bubbles grow and light scattering increases.

The resin flow rate can be adjusted by adjusting the fluidity of the resin in the prepreg, or by preheating the prepreg before the heating and pressing to adjust the fluidity of the resin in the prepreg. Can be done by

The resin flow rate and the fluidity of the resin in the prepreg can be changed by changing the amount of the resin in the fiber reinforced resin prepreg (that is, the impregnation rate of the resin with respect to the reinforcing fiber) and the pressure applied during the production of the in-molded product. Can be changed freely. Regarding the applied pressure (molding pressure) when manufacturing in-molded products, if the pressure is set too high, electronic parts may be destroyed. Therefore, the molding pressure is 10 kg / cm ²
The following is desirable.

[0019]

Example: An epoxy resin is used as a thermosetting resin, a glass fiber non-woven fabric is used as a reinforcing long fiber, and a fiber reinforced resin prepreg is prepared by impregnating this epoxy resin into a glass fiber non-woven fabric, which is preheated at 90 ° C. Then, they are laminated on both sides of the electronic component composition, and then heated by a mold having a mold temperature of 160 ° C. and pressed with a surface pressure of 5 kgf / cm ² by the mold to obtain an in-mold product with a built-in electronic component structure. As fabricated, the resin flow rate during pressurization was measured. here,
The preheating time of the prepreg was changed as a parameter.
This is because the resin flow rate is changed depending on the preheating time.

The thus obtained in-mold product with built-in electronic component composition was examined by an optical microscope for the presence of surface voids and internal voids, and was also examined by soft X-rays for the destruction of electronic components. . The results are shown in Table 1.
Shown in. The resin flow rate varies depending on the preheating time of the prepreg. When the resin flow rate is 2 wt%, surface voids and electronic parts are destroyed, and when the resin flow rate is 40 wt%, internal voids are generated. Occurrence is recognized.
On the other hand, when the resin flow rate was 5 wt% and 30 wt%, generation of surface voids and internal voids and destruction of electronic parts were not observed.

[0021]

[Table 1]

[0022]

According to the method of manufacturing an in-molded product with a built-in electronic component according to the present invention, when the in-molded product with a built-in electronic component is manufactured by changing the composition of the thermosetting resin, the surface due to the generation of surface voids Deterioration of properties, occurrence of internal voids, and occurrence of defects such as destruction of electronic components are unlikely to occur, and an in-mold product with a built-in electronic component component that does not have such defects is obtained, and the occurrence of such defects is prevented by conventional methods. There is an effect that it becomes possible to carry out relatively easily without requiring a large number of experiments as in the case of the method for manufacturing an in-molded electronic component component. Also, like the conventionally proposed in-molded electronic component component built-in product, as compared with the conventional electronic component fixing method, it is easy to be made compact, is not easily bent, and is excellent in strength and strong,
Furthermore, it also has the effect that the number of manufacturing steps can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an example of a manufacturing situation of an in-molded product with a built-in electronic component structure.

FIG. 2 is a side sectional view showing an example of an in-mold product with a built-in electronic component structure.

[Explanation of symbols]

1--long fiber reinforced resin layer, 2--printed wiring board, 3--electronic component, 4--long fiber reinforced resin prepreg sheet, 5--upper mold, 6--lower mold.

Claims (3)

[Claims] 1. An in-mold product with a built-in electronic component component, comprising laminating a fiber-reinforced resin prepreg in which a thermosetting resin is impregnated into reinforcing long fibers on one side or both sides of the electronic component component, and then heating and pressing the laminate. In the manufacturing method, the weight of the resin flowing out from the prepreg during the pressurization is adjusted to 3 to 35 wt% in terms of the ratio of the weight of the resin to the weight of the prepreg before pressurization. Manufacturing method. 2. The method for manufacturing an in-mold product with a built-in electronic component structure according to claim 1, wherein the weight of the resin flowing out from the prepreg is adjusted by adjusting the fluidity of the resin in the prepreg. 3. The electronic component component built-in according to claim 1, wherein the weight of the resin flowing out from the prepreg is adjusted by preheating the prepreg before the heating and pressing to adjust the fluidity of the resin in the prepreg. In-mold product manufacturing method.