JPH06350232A - In-molded item incorporating electronic component - Google Patents

Abstract

PURPOSE:To enhance the flatness of the surface of an in-molded item by a constitution wherein the compositional object of electronic components comprises a printed board mounting an electronic component and a printed wiring board having rigidity higher than that of the printed board and the warping thereof is eliminated or restrained. CONSTITUTION:In the in-molded item incorporating the compositional object of an electric component molded integrally in a long fiber reinforced resin layer 4, the compositional object comprises a printed board 6 mounting an electronic component 7, and a printed wiring board 5 having rigidity higher than that of the printed board 6. A pattern of communication coil is arranged on the printed wiring board 5 disposed on the outer periphery of the printed board 6. Since the in-molded item is restrained from warping due to the reinforcing effect of the printed wiring board having high rigidity during compression molding, flatness can be improved on the surface of in-molded item.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-mold product having a built-in electronic component structure, and more specifically, a structure that combines electronic components such as ICs and exhibits one or more functions such as oscillation, reception, calculation, and storage. The present invention relates to an in-mold product with a built-in electronic component structure in which a product (hereinafter referred to as an electronic component constituent) is integrally molded and embedded in a long fiber reinforced resin layer.

[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 manufactured by a method in which long-fiber-reinforced resin prepregs obtained by impregnating reinforced long fibers with a resin are laminated on both sides of an electronic component component and compression-molded by a mold at a predetermined temperature and a predetermined surface pressure. It At this time, the long fiber reinforced resin prepreg is compressed and hardened while incorporating the electronic component component into a long fiber reinforced resin layer.

Here, in order to explain the structure of the conventional in-mold product in more detail, a side sectional view of a typical example thereof is shown in FIG. In FIG. 5, 1 is a long fiber reinforced resin layer, 2 is a printed wiring board, 3 is an electronic component such as an IC, and the electronic component 3 is mounted on the printed wiring substrate 2 to form an electronic component component. . That is, the electronic component component is composed of the printed wiring board 2 on which the electronic component 3 is mounted, and the electronic component component is incorporated in the long fiber reinforced resin layer by in-mold integral molding. As described above, in the conventional in-mold product, the electronic component component is the printed wiring board on which the electronic component is mounted, and this is incorporated in the long fiber reinforced resin layer.

According to such an in-mold product having a built-in electronic component structure, the housing can be made small, which facilitates downsizing of the device. Moreover, since the device is hard to bend and has excellent strength, the peeling of the component and the IC lead wire Cutting is less likely to occur, and furthermore, 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, so the manufacturing process is greatly reduced.

[0007]

However, the conventional in-mold products with built-in electronic component components have the following problems. That is, when the in-mold product is manufactured, the compression molding is performed by the mold as described above. The flow of the long fiber reinforced resin during the compression molding, the temperature distribution in the mold, and the molding product (in-mold product) during the mold release There is a problem that warpage (warping) occurs due to the adhesion force and frictional force with the mold, and the flatness (flatness) of the surface of the in-mold product is poor.
Since the in-molded product after compression molding is hard to bend and excellent in strength as described above, it is hard to change the shape. Therefore, the warp once generated can hardly be corrected and the quality of the shape is deteriorated. In addition to this, it becomes a fatal obstacle when the transfer printing is performed on the surface of the in-molded product.

Furthermore, in order to have a communication function, when an external coil (copper wire coil having a covering material, etc.) is attached for communication, the shape of the coil has an influence, and the surface shape of the coil is the surface of the in-molded product. The surface of the in-molded product is poor in flatness due to projection (projection) on the surface, resulting in unevenness. Further, there is also a drawback that voids are generated in the long fiber reinforced resin during compression molding due to decomposition due to deterioration of the coil covering material, moisture absorption, etc., and defective products may be generated due to such voids.

The present invention has been made by paying attention to such a situation, and an object thereof is to solve the problems of the conventional in-molded electronic component component built-in products, and to eliminate warpage or warp. Provides an in-mold product with a built-in electronic component that has a sufficiently small degree of surface smoothness and has excellent surface flatness. Furthermore, even when a communication function is provided, the surface is smooth and flat. In-mold product with built-in electronic component structure that is excellent in moldability and less likely to cause defective molding, that is, molding failure due to deterioration of flatness of surface of in-mold product due to influence of communication coil shape and deterioration of coil coating material. It is an object of the present invention to provide an in-mold product with a built-in electronic component structure that can have a communication function without causing a non-defective product.

[0010]

In order to achieve the above object, the in-molded electronic component component-embedded product according to the present invention has the following configuration. That is, the in-molded product according to claim 1 is an in-molded product with a built-in electronic component structure formed by integrally molding an electronic component composition in a long fiber reinforced resin layer, wherein the electronic component composition is an electronic component. An in-mold product with a built-in electronic component, comprising a printed circuit board on which is mounted and a printed wiring board having higher rigidity than the printed circuit board.

The in-mold product according to claim 2 is the in-mold product with a built-in electronic component structure according to claim 1, wherein a pattern of a communication coil is arranged on the printed wiring board.
The in-molded product according to claim 3 is an in-molded product with a built-in electronic component structure according to claim 1 or 2, which has wiring for electrically connecting the wiring of the printed wiring board and the electronic component. .

[0012]

The in-molded electronic component component according to the present invention is, as described above, an in-molded electronic component component-embedded product obtained by integrally molding the electronic component component in the long fiber reinforced resin layer. Since the electronic component structure includes a printed circuit board on which an electronic component is mounted and a printed wiring board having a rigidity higher than that of the printed circuit board, first, basically, the conventional electronic component structure is used. As in the case of the in-mold product with built-in objects, the electronic parts function, the equipment can be easily made compact, it is hard to bend, and it has excellent strength and strength, and the manufacturing process is greatly reduced. Produce an effect.

Further, since the printed wiring board having the rigidity higher than that of the printed wiring board on which the electronic parts are mounted is provided, warpage during the compression molding is extremely unlikely to occur due to the reinforcing effect of the highly rigid printed wiring board. . That is, in the case of the conventional in-mold product, warping is apt to occur due to the flow of the resin or the like as described above at the time of compression molding by the mold that is performed during its manufacture. In this case, since a high-rigidity printed wiring board is provided, the intermediate molding product and the molded product (in-mold in-mold product) formed during compression molding are reinforced by the printed wiring board and The rigidity is high, so warpage is extremely unlikely to occur during compression molding. Therefore, the in-molded product according to the present invention has no warp or the degree of warping is sufficiently small and the surface of the in-molded product is excellent in flatness.

A pattern of a communication coil may be arranged on the printed wiring board. This can be provided by cutting a coil on the printed wiring board,
Also, no coil coating is required and the coil can be formed without the use of a coating. According to such a coil, the surface shape of the coil is less likely to be reflected on the surface of the in-mold product and unevenness is less likely to occur, as compared with the external coil (a copper wire coil having a covering material or the like) in the conventional in-mold product. Therefore, the flatness of the surface of the in-molded product is less likely to deteriorate due to the influence of the coil shape, and the problem of the occurrence of voids during compression molding due to decomposition of the coil coating material or moisture absorption can be solved.
Therefore, the communication function can be provided without causing a defective molding due to the deterioration of the flatness of the surface of the in-molded product due to the influence of the shape of the communication coil and the deterioration of the coil coating material. In other words, it is possible to obtain an in-mold product with a built-in electronic component in which molding defects are unlikely to occur even when a communication function is provided, and the surface has few irregularities and is excellent in flatness.

The high-rigidity printed wiring board is preferably arranged around the outside of the printed board on which electronic components are mounted. This is because the reinforcing effect of the high-rigidity printed wiring board can be more strongly exerted, the warp amount of the in-molded product is drastically reduced, and the flatness is improved.

The wiring for electrically connecting the wiring of the printed wiring board and the electronic component is not always required, but may be provided.

[0017]

FIG. 1 is a perspective view of an in-mold product with a built-in electronic component structure according to an embodiment of the present invention, and FIG. 2 is a side sectional view (a sectional view taken along line AB in FIG. 1). This in-mold product was manufactured as follows. First, the printed board 6 (board thickness: 0.3 mm) on which the electronic component 7 is mounted and the printed wiring board 5 (board thickness: 1.0 mm) having higher rigidity than the printed board 6 are manufactured. Here, on the printed wiring board 5, the coil was cut and a pattern (not shown) of a communication coil having no coil covering material was arranged. On the other hand, a plurality of long fiber reinforced thermosetting resin prepregs are prepared by impregnating the reinforced long fibers with a thermosetting resin. Next, the printed circuit board 6 and the printed wiring board 5 are connected by wiring,
The prepregs are laminated on both sides of them, set in a mold, and then compression-molded at a predetermined temperature and a predetermined surface pressure. Then, a molded product (in-molded product) is taken out from the mold.

The in-mold product thus obtained is, as shown in FIGS. 1 and 2, an in-mold electronic component component built-in obtained by integrally molding the electronic component component in the long fiber reinforced resin layer 4. The electronic component component is composed of a printed circuit board 6 on which an electronic component 7 is mounted and a printed wiring board 5 having higher rigidity than the printed circuit board 6. Here, a pattern of a communication coil is arranged on the printed wiring board 5. The printed wiring board 5 is arranged around the outside of the printed board 6. That is, this in-molded product is an in-molded product according to the embodiment of the present invention, and corresponds to an example of an in-molded product with a built-in electronic component structure according to claim 2. The dimensions of this in-mold product are: thickness: 2.4 mm, width: 54 mm, length:
It is 86 mm.

On the other hand, an in-mold product with a built-in electronic component structure was manufactured as a comparative example. As shown in FIGS. 3 and 4, the in-molded product according to the comparative example is an in-molded product with a built-in electronic component, which is formed by integrally molding the electronic component in the long fiber reinforced resin layer 4. The electronic component component is a printed wiring board 8 on which an electronic component 7 is mounted.
It consists of The external coils 9 and 10 made of a copper wire coil having a coating material as a communication coil are also incorporated in the long fiber reinforced resin layer 4. The dimensions of the in-molded product are the same as those of the in-molded product according to the above embodiment.

The in-molded product was placed on a flat plate and the gap between the flat plate and the in-molded product was measured. Also, the surface condition of the in-molded product was observed. The maximum value for the gap between this flat plate is the average for the in-mold product according to the comparative example.
While it was 0.65 mm (average value for a large number of sheets), it was 0.60 mm or less in the in-mold product according to the example of the present invention, and the flatness (flatness) of the surface of the in-mold product was excellent.

Further, in the in-molded product according to the comparative example, as shown in FIG. 4, the external coils 9 and 10 made of copper wire coils are used.
The surface shape of No. 3 was reflected on the surface of the in-molded product, and unevenness was generated on the surface. On the other hand, in the in-molded product according to the embodiment of the present invention, such unevenness hardly occurs, the difference between the convex portion slightly generated for some reason and the flat surface portion 11 of the in-molded product surface is 0.05 mm or less. The surface flatness (surface flatness) was excellent.

[0022]

EFFECT OF THE INVENTION The in-molded electronic component component-embedded product according to the present invention has the above-described structure and operates, and solves the problems of the conventional in-molded electronic component component-embedded product. However, due to the reinforcing effect of the high-rigidity printed wiring board, warpage during compression molding of in-mold products is extremely unlikely to occur, so there is no warp or the warpage is sufficiently small that the surface of the in-mold product is flat. It has excellent properties. Further, even when it is provided with a communication function, the surface has few irregularities, the planar smoothness is excellent, and a defective molded product is unlikely to occur. That is, unlike the case of the conventional in-molded product with built-in electronic component components, the flatness of the surface of the in-molded product is deteriorated due to the influence of the shape of the communication coil, and the defective molded product is caused by the deterioration of the coil coating material. Instead, it may have a communication function. Therefore, it becomes possible to improve the quality of the shape such as flatness and flatness, and
The present invention has an effect that it can be preferably used when planar smoothness is required as an in-molded product such as when transfer printing is performed on the surface of the in-molded product.

Further, as in the case of the in-mold product with a built-in electronic component structure of the above-mentioned conventional proposal, compared to the conventional electronic component fixing method, it is easy to be made compact, it is hard to bend, and it is excellent in strength and strong. At the same time, it also has the effect that the manufacturing process can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a perspective view showing an outline of an in-mold product with a built-in electronic component structure according to an embodiment of the present invention.

FIG. 2 is a side sectional view showing the outline of an in-mold product with a built-in electronic component structure according to an embodiment of the present invention.

FIG. 3 is a perspective view showing the outline of an in-mold product with a built-in electronic component structure according to a comparative example.

FIG. 4 is a side sectional view showing an outline of an in-mold product with a built-in electronic component structure according to a comparative example.

FIG. 5 is a side sectional view showing an outline of a conventional 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 layer, 5--printed wiring board, 6--printed board, 7--electronic component, 8--Printed wiring board, 9,10--External coil, 11--Flat part of in-mold product.

Claims (3)

[Claims] 1. An in-mold product with a built-in electronic component structure, which is obtained by integrally molding an electronic component structure in a long fiber reinforced resin layer, wherein the electronic component structure is a printed circuit board on which an electronic component is mounted, An in-mold product with a built-in electronic component, comprising a printed wiring board having higher rigidity than the printed board. 2. The in-mold product with a built-in electronic component structure according to claim 1, wherein a pattern of a communication coil is arranged on the printed wiring board. 3. The in-mold product with a built-in electronic component structure according to claim 1, further comprising a wiring that electrically connects the wiring of the printed wiring board and the electronic component.