JPH05261744A - Method and apparatus for producing molded product having interior object sealed therein - Google Patents

Abstract

PURPOSE:To strongly and closely seal a film like interior object in a molded product at a specified position. CONSTITUTION:A pinch-off groove 6b and a material sump groove 6c are formed to the outer periphery of the cavity 6a of a first mold 6 and the fine groove 6d allowing the cavity 6a to communicate with the pinch-off groove 6b and the material sump groove 6c is formed. When internal pressure is applied to the curable molding material received in the cavity 6a, said pressure escapes to the pinch-off groove 6b or the material sump groove 6c through the fine groove 6d.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing a molded product containing an interior product such as a film.

[0002]

BACKGROUND ART With the recent miniaturization and thinning of electronic parts,
There is a demand for a technique for accurately coating these electronic components with an outermost thin film. As an example, as shown in FIGS. 9 and 10, a thickness of 1.8 mm to 4.
The printed board 5 is attached to the molded product 52 of a rubber sheet having a thickness of about 0 mm.
In the case of enclosing 0, for example, there is a method in which a molded product of the upper surface portion 52a and a lower surface portion 52a of the molded product 52 is manufactured, and the molded product is sandwiched and fixed with an adhesive or the like. However, in this method, the manufacturing process is complicated, the printed board 50 is peeled off due to the change in the outer shape of the molded product 52, or the watertightness (airtightness) is not sufficient, so that the printed board 50 is deteriorated due to invading water or the like. There is a problem.

From the above, the present inventor first crimps the upper and lower molds with the printed circuit board 50 sandwiched between them when the thermosetting molding material in the cavities of the upper and lower molds is in an unvulcanized state.
After that, by curing the thermosetting molding material,
A method of enclosing the printed circuit board 50 in a thin-walled molded product has been proposed (Japanese Patent Application No. 3-112270). By this method, the adhesion, adhesion strength, etc. between the printed circuit board 50 and the molded product are remarkably improved, but when mass-producing the molded product, the quality stability becomes a problem.

That is, as shown in FIG. 7, the upper and lower molds 60,
When the thermosetting molding material 70, 70 is loaded into the cavities 60a, 61a of the mold 61 through a pot mold (not shown), the thermosetting molding material (tablet) may be loaded depending on the loading amount of the thermosetting molding material (tablet). The molding material 70, 70 is molded in a state of being raised above the plane of the upper and lower molds 60, 61. The thermosetting molding material leaked from the cavities 60a and 61a is received by the cutting grooves 60b and 61b and the material collecting grooves 60c and 61c.

The thermosetting molding materials 70, 70 of the cavities 60a, 61a are in an unvulcanized state, and the cutting groove 60b,
After removing the thermosetting molding material leaked in 61b, as shown in FIG. 8, the thermosetting molding material 7 of the lower mold 61 is removed.
Printed circuit board 50 is placed on top of
Crimp.

At this time, a large pressing force is applied to the thermosetting molding material in the mold cavity, and the raised portions of the thermosetting molding material described above are cut grooves 60b and 61b formed on the outer periphery of the cavity and the material. At the same time when the thermosetting molding material leaks into the reservoir grooves 60c and 61c, the thermosetting molding material in the cavity also moves in a complicated manner. Therefore, when the thermosetting molding material is cured to form a product, the printed circuit board, which is an interior product, is deformed or the printed circuit board is displaced, and in an extreme case, it is connected to the printed circuit board 50. The contact fitting 51 may be deformed or broken.

Also, using an automatic press-fitting molding machine, the upper and lower molds 6
There is also a method in which the cavities 60a and 61a of 0 and 61 are filled with an accurate amount of the thermosetting molding material to prevent the above-mentioned raised portion from occurring. However, even in this case, when the printed circuit board 50 is sandwiched and pressure-bonded, the thermosetting molding material corresponding to the volume of the printed circuit board 50 leaks from the cavity, and the thermosetting molding material moves due to the leakage. Problem arises. A method of subtracting a thermosetting molding material in an amount equal to the volume of the printed circuit board 50 and loading it in the cavity is also conceivable, but it is difficult to adjust the loading amount, and the adhesiveness decreases due to insufficient loading of the thermosetting molding material. There are problems such as occurrence of.

[0008]

SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a manufacturing method for accurately enclosing an interior product in a predetermined position of a molded product and firmly adhering the interior product and the molded product together with the manufacture thereof. The purpose is to provide a device.

[0009]

The first means of the present invention adopted to solve the above-mentioned problems is to load the thermosetting molding material into the cavities of the first mold and the second mold, respectively. After interposing an interior product between thermosetting molding materials, the two dies are thermocompression bonded to each other, and the thermosetting molding material is integrated and cured. The mold and / or the second mold is provided with a pressure relief portion, and when the thermosetting molding material is in a non-vulcanized state before being cured, the thermosetting molding material is provided with an interior part to interpose the first part. The mold and the second mold are pressure-bonded to each other, and the pressure applied to the thermosetting molding material at this time is released to the outside of the cavity through the pressure relief portion. The second means of the present invention is that the thermosetting molding material is silicone rubber and the mold temperature is 100 ° C.
It is characterized in that it is ˜160 ° C. A third means of the present invention is characterized in that the molded product is band-shaped and the interior product is a film. The fourth means of the present invention is to load the thermosetting molding material into the cavities of the first mold and the second mold, respectively, and to interpose the interior article between the thermosetting molding materials, and In a device for manufacturing a molded product in which a mold is thermocompression-bonded, and a thermosetting molding material is integrated and cured, an interior product is enclosed, and both molds are thermocompressed to the first mold and / or the second mold. At this time, a pressure relief portion is provided for escaping the pressure applied to the thermosetting molding material in the cavity to the outside of the cavity. A fifth means of the present invention is characterized in that the pressure relief portion is a fine groove that communicates the mold cavity with a groove portion formed on the outer periphery of the cavity. A sixth means of the present invention is characterized in that the pressure relief portion is a narrow groove that communicates the mold cavity with the outside of the mold.

[0010]

EXAMPLES Next, examples of the present invention will be described in the case of manufacturing the molded product shown in FIGS. 9 and 10, specifically, a rubber watch band enclosing a printed circuit board. FIG. 1 shows an automatic press-fitting molding machine used in this embodiment, which includes a press-fitting cylinder-1, a pot portion 2, a distribution board 3,
A mold clamping cylinder-4 is provided. Press-fit cylinder-1
The pot portion 2 and the mold clamping cylinder 4 are connected by a tie bar 5, and the pot portion 2 and the distribution board 3 are connected by a flange 8.

A first mold 6 as an upper mold and a second mold 7 as a lower mold are mounted on a base 4a of the mold clamping cylinder-4.
By raising the mold clamping cylinder-4, these molds 6 and 7 are pressed onto the lower surface of the distribution board 3. The chamber 2a of the pot portion 2 is loaded with a thermosetting molding material 10 (pallet), and the thermosetting molding material 10 is pressed down by the pressing portion 1a of the press-fitting cylinder-1 so that the gate 9 and the distribution board. It is loaded into the cavities of the upper and lower molds 6 and 7 via the branch path 3a of 3. A release film made of fluorine resin or the like is formed on the lower surface of the distribution board 3 so that the thermosetting molding material in the mold cavity will not adhere to it.

Next, as shown in FIG. 2, the printed circuit board having the contact point 11a as shown in FIG. 3 on the thermosetting molding material 10 of the second mold 7 with the first mold 6 facing downward. 1
In the state where 1 is placed, both molds 6 and 7 are pressure-bonded, the thermosetting molding materials 10 and 10 are integrated, and then cured.

The first mold 6 and the second mold 7 are formed with cavities 6a, 7a corresponding to the band shape to be molded,
The cutting grooves 6b and 7b and the material collecting grooves 7c and 7 are provided on the outer periphery thereof.
c is formed. The thermosetting molding materials 10 and 10 leaking from the cavities when the molds 6 and 7 are pressure-bonded are collected in the bite grooves 6b and 7b and the material pool grooves 6c and 7c, and after hardening, the bite grooves 6b and 7b are cured. At, the leaked part is cut and removed.

FIG. 4 shows a plan view of the first die 6.
The tip of the cavity 6a of the first mold 6 is formed with a thin groove 6d which connects the cavity 6a with the cutting groove 6b and the material collecting groove 6c. Although not shown, a fine groove is similarly formed in the cavity 7a of the second mold 7. Therefore, when the two molds 6 and 7 are pressure-bonded, the pressure applied to the thermosetting molding materials 10 and 10 in the cavity is a narrow groove 6d (the narrow grooves of the upper and lower molds are combined to form a thin hole). ) Escape to the outside of the cavity. That is, the thermosetting molding material 1 corresponding to the volume of the printed circuit board 11
A part of 0 and 10 will flow out into the biting grooves 6b and 7b and the material collecting grooves 6c and 7c through the narrow groove 6d.

The narrow groove 6d has a depth of 0.2 mm to 0.
The width is 3 mm and the width is 1 to 1.5 mm, and the optimum size is selected in consideration of the volume of the cavity 6a, the viscosity of the thermosetting molding material 10, and the like. If the narrow groove 6d is too large, the thermosetting molding material flows out rapidly, so that the thermosetting molding material 10 in the cavity 6a also moves largely in the narrow groove direction, and the printed circuit board 11 is likely to be displaced. In addition, narrow groove 6d
If is too small, the pressure applied to the thermosetting molding material 10 in the cavity 6a cannot be sufficiently released, so that the printed circuit board 11 is displaced and deformed as in the conventional case.

5 and 6 show another embodiment of the present invention. In this embodiment, for example, a material collecting groove 20 having a volume capable of accommodating the thermosetting molding material leaking from the cavity 7a is formed in the direction of the tip of the cavity 7a of the second mold 7 serving as the lower mold. A narrow groove 21 is formed which extends from the cavity 7a to the outside of the mold through the material pool groove 20. Further, as shown in FIG. 6, the first mold 6 is also formed with a narrow groove 21a corresponding to the narrow groove 21 and extending through the cavity 6a and the outside of the mold. In this embodiment, the material collecting grooves 6c and 7c on the outer periphery of the cavity are omitted, and only the cutting grooves 6b and 7b are formed.

In the case of the above-described embodiment, the thermosetting molding material leaked from the cavities 6a and 7a when the two dies 6 and 7 are pressure-bonded to each other from the small holes formed by the fine grooves 21 and 21a to the material collecting groove. 20 and the internal pressure of the cavity escapes through the small holes to the outside of the mold.

In the above-described embodiment, a pressure relief thin groove is formed at the tip of the mold cavity, but since this cavity has a band shape, it is thermosetting when internal pressure is applied. This is because the material tends to move in the cavity length direction. Therefore, the narrow groove may be formed at an optimum position according to the shape of the cavity. The narrow groove may be provided in either the first mold or the second mold.

The thermosetting molding material 10 is specifically a thermosetting rubber such as silicone rubber or a thermosetting resin such as epoxy resin, phenol resin or silicone resin.
The printed circuit board 11 is a polyimide resin film having a thickness of 0.1 mm, and a circuit such as an antenna circuit is printed on the surface thereof. The wall thickness of the molded product molded in this example is 1.8 mm to 4.0 mm. Further, the heating temperature of the pot portion 2 of this embodiment is 100 degrees or less.

According to the present invention, when the thermosetting molding material 10 loaded in both molds 6 and 7 is in an unvulcanized state, the thermosetting molding material 10 loaded in the second mold cavity 7a is The printed circuit board 11 is placed on and the two molds 6 and 7 are pressure-bonded to each other so that the thermosetting molding material of the mold is integrated and cured.

In this case, the heating temperature of the first mold 6 and the second mold 7 is 100 ° C to 160 ° C, preferably 130 ° C to 15 ° C.
It is 5 ° C. Generally, the thermosetting molding material 10 is made of silicone.
In the case of rubber, the optimum vulcanization temperature is about 170 ° C. However, according to the experiment of the inventor, the mold temperature is 170 ° C.
When heated up to this point, the adhesiveness between the cured silicone rubber and the printed circuit board 11 is poor, and for example, a gap may occur between the cured silicone rubber and the printed circuit board 11. Table 1 shows
The results are obtained by investigating the adhesiveness between the cured silicone rubber and the printed circuit board (the substrate material is a polyimide resin film) and the economical efficiency as a rubber molded product by variously changing the mold temperature.

[0022]

[Table 1] Evaluation X: Very good Y: Good Z: Poor

As is clear from the above table, the adhesiveness between the silicone rubber and the printed circuit board is such that the mold temperature is 150 ° C to 1 ° C.
55 ° C is the best. At 100 ° C. to 140 ° C., the printed circuit board was wavy or some of the silicone rubber contained air bubbles, but there was no problem in terms of adhesion. When the mold temperature was 160 ° C., a slight non-adhered portion was observed, but if it is negligible, it can be put to practical use. If the temperature exceeds 170 ° C., the non-adhesive portion increases and it cannot be put to practical use. The term "adhesion" as used herein means that the contact surface between the silicone rubber and the printed circuit board is completely adhered to each other without forming voids, and the printed circuit board is integrated with the silicone rubber so that the printed circuit board cannot be pulled out from the silicone rubber. It is fixed to.

The economical efficiency in Table 1 is a practical manufacturing time for manufacturing a molded product. Mold temperature is 150 ℃
When the temperature is ˜155 ° C., the vulcanization time of the silicone rubber is within 10 minutes, and the production is extremely efficient. When the mold temperature is 130 ° C. to 140 ° C., the vulcanization time is 20 minutes or less, which is slightly slower, but it can be put to practical use. However, when the temperature is 120 ° C. or lower, a vulcanization time of 20 minutes or more is required, which is not practical. Further, if the mold temperature is 170 ° C. or higher, it is uneconomical because the mold temperature must be cooled to about 170 ° C. at which the adhesion is good. However, if economy is ignored, as long as the above-mentioned adhesion can be secured,
The mold temperature may be 0 ° C. or lower or 170 ° C. or higher.

When the interior product lacks affinity for the thermosetting molding material 10 in the unvulcanized state, an adhesive having an affinity for the thermosetting molding material is applied to the surface of the interior product, You may perform required surface treatment.

In the above-mentioned embodiment, the molded product of the watch band is explained as an example, but a flexible printed circuit board in which electronic parts are incorporated may be enclosed in another band-shaped molded product. Further, as another application example, it is also suitable for accurately and watertightly encapsulating a film-shaped or piece-shaped material in a molded product. The shape of the molded article of the present invention is arbitrary,
The configuration of the mold and the like is also changed according to the shape of the molded product. In addition, the configuration of the illustrated mold is for convenience of explaining the present invention, and can be arbitrarily changed as necessary.

[0027]

According to the present invention described above, in encapsulating an interior product in a molded product, when the thermosetting molding material is in an unvulcanized state, the interior product is encapsulated and the thermosetting molding material adheres. Of the thermosetting molding material is released to the outside of the cavity when the metal mold is pressed and the mold is pressed, so that the interior product is firmly deformed and positioned at a predetermined position. Enclosed in close contact.

[Brief description of drawings]

FIG. 1 is a schematic view of an automatic press-fitting molding machine used in an example of the present invention.

FIG. 2 is a schematic cross-sectional view of a first mold and a second mold for explaining an embodiment of the present invention.

FIG. 3 is a schematic view of a printed circuit board used in an example of the present invention.

FIG. 4 is a schematic plan view of a first mold showing an embodiment of the present invention.

FIG. 5 is a schematic plan view of a second mold showing another embodiment of the present invention.

6 is a schematic plan view of a first mold corresponding to the second mold shown in FIG.

FIG. 7 is a schematic sectional view of a mold for explaining a conventional method.

FIG. 8 is a schematic sectional view of a mold for explaining a conventional method.

FIG. 9 is a schematic plan view of a molded product molded in the example of the present invention.

FIG. 10 is a schematic cross-sectional view of the molded product shown in FIG.

[Explanation of symbols]

 6 First mold 6a First mold cavity 6b Eating groove 6c Dough collecting groove 6d Pressure relief fine groove 7 Second mold 7a Second mold cavity 7b Eating groove 7c Dough collecting groove 11 Printed board 20 Dough collecting Groove 21 Fine groove 21a Fine groove

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Claims (6)

[Claims] 1. A thermosetting molding material is loaded into each of the cavities of the first mold and the second mold, and an interior article is interposed between both thermosetting molding materials, and then the two molds are heated and pressure bonded. In the method for producing a molded product that encloses an interior product in which a thermosetting molding material is integrated and cured, a pressure relief portion is provided in the first mold and / or the second mold, and the thermosetting molding is performed. When the material is in an unvulcanized state before it is cured, the thermosetting molding material is pressure-bonded to the first mold and the second mold with the interior parts interposed, and the pressure applied to the thermosetting molding material at this time. A method for manufacturing a molded article in which an interior product is enclosed, characterized in that the pressure product is released to the outside of the cavity via the pressure relief portion. 2. The method for producing a molded article enclosing an interior product according to claim 1, wherein the thermosetting molding material is silicone rubber and the mold temperature is 100 ° C. to 160 ° C. 3. The method for producing a molded product encapsulating an interior product according to claim 1, wherein the molded product has a band shape and the interior product is a film. 4. A thermosetting molding material is loaded into each of the cavities of the first mold and the second mold, an interior article is interposed between the thermosetting molding materials, and then the two molds are heated and pressure bonded. Then, in a molding product manufacturing apparatus that encapsulates an interior product that integrally cures a thermosetting molding material, in a cavity when the two molds are thermocompression bonded to the first mold and / or the second mold. An apparatus for manufacturing a molded product in which an interior product is enclosed, characterized in that a pressure relief portion is provided to release the pressure applied to the thermosetting molding material to the outside of the cavity. 5. The molded article in which the interior component is enclosed according to claim 4, wherein the pressure relief portion is a narrow groove that communicates the mold cavity with a groove portion formed on the outer periphery of the cavity. Manufacturing equipment. 6. The apparatus for manufacturing a molded product enclosing an interior product according to claim 4, wherein the pressure relief portion is a narrow groove that communicates the mold cavity with the outside of the mold.