JPH11300781A - Molding method for resin and mold equipment for molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a molding method for a resin wherein after the resin for molding is supplied into a cavity and molded, a first mold and a second mold are separated and a cured material of the resin for molding is removed and formed and wherein the cured material of the resin for molding can be removed in a joined state and is hardly left in the mold, and mold equipment for molding which allows removal of the cured material of the resin for molding in the joined state and makes the cured material hardly left in the mold. SOLUTION: A counter plunger 18 is provided beforehand so that it is opposed to an injection plunger 17, on the other side of a face whereon a first mold 11 and a second mold 12 come into contact with each other. After the injection plunger 17 and the counter plunger 18 are separated from a cured material B of resin for molding in a state wherein the first mold 11 and the second mold 12 are brought into contact with each other, the first mold 11 and the second mold 12 are separated and the cured material B of the resin for molding is removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin molding method for molding by transfer molding, and a molding die apparatus used for the resin molding method.

[0002]

2. Description of the Related Art As a method for encapsulating electronic parts and manufacturing tableware and the like, a method of molding by transfer molding using a molding resin such as an epoxy resin is widely used.

As a method of molding by the transfer molding, for example, as shown in FIG. 4 (a), a first mold 31 and a first mold 31 are disposed so as to face the first mold 31. Second mold 32 formed so as to be able to contact and separate from 31
And a resin molding cavity 33 formed between the first mold 31 and the second mold 32 when they are brought into contact with each other.
A pot 36 for storing a molding resin A to be supplied to the cavity 33; an injection plunger 37 slidably provided with respect to the pot 36;
6 and the cavity 33, and a molding die apparatus having a transfer passage 34 for transferring the molding resin A from the pot 36 to the cavity 33 is used.

After mounting a lead frame 39 on which component elements are mounted as necessary, the first mold 31 and the second mold 32 are brought into contact with each other, and then the molding resin A stored in the pot 36 is formed. Is extruded by the injection plunger 37 and supplied into the cavity 33, and then the molding resin in the cavity 33 is heated and cured by the first mold 31 and the second mold 32. Next, as shown in FIG.
The first and second molds 32 are separated from each other to cure the molding resin B
The molding is performed by a method of taking out.

In the second mold 32, an eject pin 35 for peeling off the cured product B of the molding resin from the second mold 32 is provided so as to protrude into the cavity 33, as shown in FIG. When the molding resin A is supplied into the cavity 33 as shown in FIG.
When hardening, the eject pin 35 is disposed so as to be flush with the bottom surface of the cavity 33, and FIG.
When taking out the cured product B of the molding resin as shown in FIG. 1, the ejected pin 35 is pressed by the eject pin 35 so that the eject pin 35 projects into the cavity 33 and the cured product B is removed from the second mold. 32 to be taken out.

[0006] The above cured product B is supplied to the cavity 33
, The cured product B cured in the portion of the transfer passage 34, and the cured product B cured of the molding resin remaining in the pot 36 are in a connected state. By pressing the cured product B cured in the cavity 33 with the eject pin 35, the cured product B can be taken out in a connected state.

However, when the molding resin A having a high adhesive strength is used, when the cured product B is pressed by the eject pin 35, a crack occurs in the cured product B and the inside of the pot 36 or the like is generated. In some cases, part of the cured product B remained. In this case, the molding resin A becomes difficult to be sent to the cavity 33 at the time of subsequent molding, which may cause a problem that the quality of a molded product obtained thereafter deteriorates. There is a need for a resin molding method that can be taken out and hardly causes the cured product B to remain in the mold.

For this reason, for example, Japanese Patent Application Laid-Open No. 2-266907
As described in No. 2, after separating the injection plunger from the cured product of the molding resin in a state where the first mold and the second mold are in contact with each other, the first mold and the second mold And a method of taking out the cured product of the molding resin by separating the first mold and the second mold in a state where the injection plunger is in contact with the cured product of the molding resin. Separating the injection plunger and the cured resin of the molding resin at the same time as separating the first mold and the second mold by separating the cured resin of the molding resin from the cured resin of the molding resin. For example, a method of taking out a cured product of a molding resin by using the method has been studied.

However, in any of these methods, the cured product may remain in the mold, and a resin molding method in which the cured product is less likely to remain in the mold is desired.

[0010]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to make a molding resin stored in a pot compatible with a first mold. After the second mold is brought into contact with the cavity and formed by extruding and supplying with the injection plunger into the cavity formed therebetween, the first mold and the second mold are separated from each other. This is a resin molding method in which a cured product of the molding resin is taken out and molded, and the cured product obtained by curing the molding resin can be taken out in a connected state, and the cured product is less likely to remain in the mold. To provide. Another object of the present invention is to provide a molding die apparatus which can be used in this resin molding method and can take out a cured product obtained by curing a molding resin in a connected state, and the cured product hardly remains in a mold.

[0011]

According to a first aspect of the present invention, there is provided a resin molding method comprising the steps of:
After the first mold and the second mold are extruded and supplied by an injection plunger into a cavity formed between the first mold and the second mold when they are brought into contact with each other, the first mold and the second mold are formed. In a resin molding method of separating a mold and taking out a cured product of a molding resin and molding, a method of separating a first mold and a second mold and taking out a cured product of the molding resin is a first metal mold. A plunger is provided so as to face the injection plunger with the surface where the mold and the second mold abut, and molding is performed with the first mold and the second mold in contact with each other. After the injection plunger and the plunger are separated from the cured resin, the first mold and the second mold are separated from each other to take out the cured molding resin.

[0012] The resin molding method according to claim 2 of the present invention comprises:
2. The resin molding method according to claim 1, wherein the injection mold and the plunger are separated from the cured product of the molding resin while the first mold and the second mold are in contact with each other. A method of taking out the cured product of the molding resin by separating the mold and the second mold, the injection plunger and the injection mold from the cured product of the molding resin in a state where the first mold and the second mold are in contact with each other. After separating the plunger, the injection plunger and the plunger are brought into contact with the cured product of the molding resin, and then the first die and the second die are separated from each other. The method is characterized in that the upper plunger of the pair of plungers is separated from the cured product of the molding resin to take out the cured product of the molding resin.

According to a third aspect of the present invention, there is provided a molding die apparatus, comprising: a first die; a second die disposed so as to be able to contact and separate from the first die; A cavity formed between the two molds when they are brought into contact with each other, and a cavity formed between them when the first mold and the second mold are brought into contact with each other. A transfer passage for supplying resin for use, an eject pin protrudably provided in the cavity, and an opening arranged on the first mold so as to open on a surface where the first mold and the second mold abut. And a pot capable of storing a molding resin, and slidably provided on an inner wall surface of the pot, and by pressurizing the molding resin in the pot, a molding resin is formed in a cavity through a transfer passage. And an injection plunger capable of supplying the cured product of the molding resin by separating the first mold and the second mold. In a molding die device formed so as to be able to be taken out, the molding die device is formed at a portion facing the injection plunger across a surface where the first die and the second die abut, and slides with the second die. The plunger is also provided freely, and the first mold and the second mold are brought into contact before the first mold and the second mold are separated and the cured product of the molding resin is taken out. After the injection plunger and the counter plunger are separated from the cured product of the molding resin in this state, the first mold and the second mold are formed to be separated from each other.

According to a fourth aspect of the present invention, there is provided a molding die apparatus according to the third aspect, wherein the first mold and the second mold are brought into contact with each other. After the injection plunger and the plunger are separated from the cured product, the injection plunger and the plunger are brought into contact with the cured product of the molding resin, and then the first die and the second die are separated. It is characterized by being formed as follows.

The portion of the surface of the injection plunger that comes into contact with the cured product of the molding resin and the portion that faces the injection plunger are easily shaved by the pressure at the time of extruding the molding resin and are easily roughened. It is considered that the adhesive strength to the cured product of the molding resin is higher than that of the portion or the portion of the transfer passage. Therefore, in the case of the conventional method, when the cured product of the molding resin is taken out by pressing with an eject pin, there is a large difference depending on the position of the difficulty in peeling, and a portion that is quickly peeled off and a portion that is difficult to be peeled off are generated. It is considered that a bending force is applied to the cured product and cracks occur between the injection plunger and the transfer passage.

However, as in the present invention, the plunger is provided so as to face the injection plunger, and after separating the injection plunger and the plunger from the cured product of the molding resin, the first mold is formed. In the case of the method of separating the injection plunger and the second mold from the second mold, since the part of the injection plunger and the counter plunger having a high adhesive strength is peeled off first, when the hardened material is pressed with the eject pin, it is difficult to peel off. The difference becomes smaller. Therefore, cracks are less likely to occur in the middle of the cured product, and the cured product is less likely to remain in the mold.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A resin molding method and a molding die apparatus according to the present invention will be described with reference to the drawings. 1 and 2
FIG. 1 is a cutaway front view illustrating an embodiment of a resin molding method and a molding die apparatus according to the present invention. FIG. 3 is a resin molding method and a molding die apparatus according to the present invention. It is the front view which showed and fractured and demonstrated other Embodiment of this invention.

In one embodiment of the resin molding method according to the present invention, a molding die apparatus as shown in FIG. 2 (a molding die apparatus according to claim 3 of the present invention) is used. This molding apparatus is a molding apparatus including a first mold 11 and a second mold 12 disposed to face the first mold 11.
The second mold 12 is disposed so as to be able to contact and separate from the first mold 11, and the first mold 11 and the second mold 12 are
A heater and a temperature sensor (both not shown) are provided inside or outside so that the temperature can be adjusted. When the first mold 11 and the second mold 12 are brought into contact with each other, a cavity 13 for molding resin and a transfer cavity for supplying molding resin A to the cavity 13 are provided therebetween. Passage 1
4 are formed. An eject pin 15 is provided on the second mold 12 so as to protrude into the cavity 13.

A pot 16 is disposed in the first mold 11 so as to open on a surface that comes into contact with the second mold 12, and the pot 16 is slidably injected into the inner wall surface of the pot 16. A plunger 17 is provided. And the second mold 12
Is provided with a plunger 18 at a position facing the injection plunger 17 with a surface in contact with the first mold 11, and the plunger 18 is slidable with the second mold 12. It is provided in.

When molding is to be started, if necessary, a lead frame in which component elements such as a capacitor element and a semiconductor element are mounted at predetermined positions is inserted into the first mold 1.
It is mounted between the first mold 12 and the second mold 12. Next, the pot 16
The molding resin A is liquefied by storing and heating the solid molding resin A therein, and then extruded by the injection plunger 17 as shown in FIG.
4, the molding resin A is supplied to the cavity 13. At this time, the plunger 18 is connected to the first mold 11.
The molding resin A is supplied at a position close to the position and at a position where the transfer passage 14 is not closed.

Before supplying the molding resin A to the cavity 13, the plunger 18 is raised until it contacts the first mold 11 to close the transfer passage 14. By pressing the molding resin A between the plungers 18 to reduce the air inside the molding resin A, the plungers 18 are separated from the first mold 11 and can pass through the transfer passage 14. In the way
The molding resin A may be supplied to the cavity 13. In this case, air bubbles are less likely to be generated inside the obtained molded product, which is preferable.

Next, after heating for a predetermined time to cure the molding resin A, the first mold 11 and the second mold 12 are separated from each other, and then pressurized by the eject pin 15 to cure the molding resin A. The molding is performed by a method of taking out B. At this time, before the first mold 11 and the second mold 12 are separated from each other and the cured product B of the molding resin is taken out, as shown in FIG. After the injection plunger 17 and the plunger 18 are separated from the cured product B of the molding resin in a state where the mold 12 is in contact with the mold 12, as shown in FIG. It is important that the cured product B of the molding resin is taken out by separating the first mold 12 from the second mold 12.

With the first mold 11 and the second mold 12 in contact with each other, the injection plunger 1
7 and the plunger 18 are separated from each other.
1 and the second mold 12 are separated from each other to cure the molding resin B
When the resin is taken out, cracks are less likely to occur in the cured product B, and the cured product is less likely to remain in the mold. This is a portion of the surface of the injection plunger 17 that comes into contact with the cured product B of the molding resin and a portion that faces the injection plunger (in the case of the present invention, the surface of the plunger 18; the conventional method shown in FIG. 4). In the case of, the part of the second mold 32) is easily shaved and roughened by the pressure at the time of extruding the molding resin A, and therefore, compared with the part of the cavity 13 and the part of the transfer passage 14, It is considered that the adhesive strength between the resin for use and the cured product B is high. Therefore, in the case of the conventional method, when the cured product B of the molding resin is taken out by pressing with the eject pin 15, there is a large difference depending on the position of difficulty in peeling,
It is considered that since a portion that peels off quickly and a portion that does not easily peel off occur, a bending force is applied to the cured product B of the molding resin, and a crack is generated between the injection plunger 17 and the transfer passage.

However, as in the present invention, the plunger 18 is provided so as to face the injection plunger 17, and after the injection plunger 17 and the plunger 18 are separated from the cured product B of the molding resin. In the case of the method in which the first mold 11 and the second mold 12 are separated from each other, the portions of the injection plunger 17 and the plunger 18 having a high adhesive force are peeled off first, so that the cured product B
When the pressure is applied, the difference in the difficulty of peeling is reduced. Therefore, cracks are less likely to occur in the middle of the cured product B, and the cured product B is less likely to remain in the mold.

A step of separating the injection plunger 17 and the plunger 18 from the cured product B of the molding resin while the first mold 11 and the second mold 12 are in contact with each other;
As shown in FIG. 3A, during the step of separating the first mold 11 and the second mold 12 to take out the cured product B of the molding resin, the injection plunger 17 and the paired plunger 18 are moved. After being brought into contact with the cured product B of the molding resin again, the first mold 1
At the same time that the first and second molds 12 are separated from each other, the injection plunger 17 (the upper plunger of the injection plunger 17 and the paired plunger 18 in this embodiment) is also cured with the molding resin. The cured product B of the molding resin may be taken out by separating from the product B and then applying pressure by the eject pin 15.

When the cured product B of the molding resin is taken out by applying pressure with the eject pin 15, the plunger 18
If (the lower plunger of the injection plunger 17 and the counter plunger 18 in this embodiment) is also pressed to take out the cured product B of the molding resin,
Since the force for peeling the cured product B of the molding resin is equalized, the cured product B of the molding resin is less likely to be cracked, and the cured product is less likely to remain in the mold, which is preferable. In this case, the plunger 18 and the eject pin 1
When 5 is simultaneously pressed after abutting on the cured product B of the molding resin, the stress applied to the cured product B is stabilized, so that the cured product B of the molding resin is less likely to be cracked, which is preferable.

The plunger 18 (the injection plunger 17 and the plunger 1 in this embodiment)
In the case of the method of taking out the cured product B of the molding resin by pressurizing even the lower plunger 8 of FIG.
7 (in the case of this embodiment, the upper plunger of the injection plunger 17 and the counter plunger 18) also contacts the cured product B of the molding resin and then the counter plunger 1
8 and the eject pin 15, it is possible to stabilize the pressing force of the plunger 18 by partially receiving it by the injection plunger 17, so that the cured product B of the molding resin is particularly cracked. This is preferable because it is difficult to perform.

Examples of the molding resin A used in the present invention include a columnar resin having a cross section substantially similar to the shape of the opening of the pot 16, a resin granulated, and a pulverized resin. In the case of granulated resin, the resin can be housed in pots 16 of various sizes and molded.
Since it is excellent in versatility and contains less fine particles than the pulverized resin, it is preferable that the fine particles do not easily scatter and stain the periphery of the molding die apparatus. As the size of the granular resin, a resin having an average particle size of about 0.3 to 1 mm is preferable because of excellent storability.

As described above, in the case of the molding resin A in which a gap is formed between the resins when stored in the pot 16 such as a granular resin or a crushed resin, as described above, the molding plunger 17 is paired with the injection plunger 17. It is preferable to supply the resin to the cavity 13 after the air inside the molding resin A is reduced by pressurizing the molding resin A between the plungers 18.

The material of the molding resin A is not particularly limited, and various materials such as a thermosetting resin such as an epoxy resin and a thermosetting resin blended with an inorganic filler and the like can be used. . When heating and curing the molding resin A, the temperatures of the first mold 11 and the second mold 12 are appropriately adjusted and heated in accordance with the curing temperature of the molding resin used.

[0031]

According to the resin molding method of the present invention, a pair of plungers is provided so as to face an injection plunger with a surface where a first mold and a second mold abut against each other. After the injection plunger and the plunger are separated from the cured product of the molding resin in a state where the molding resin is brought into contact with the second mold, the molding resin is separated by separating the first mold and the second mold. In this case, the cured product of the molding resin is hardly left in the mold.

The molding die apparatus according to the present invention is formed at a portion facing the injection plunger with a surface where the first die and the second die abut, and slidable with the second die. The first mold and the second mold are brought into contact with each other before the first mold and the second mold are separated and the cured product of the molding resin is taken out. After the injection plunger and the counter plunger are separated from the cured product of the molding resin in the inclined state, the first mold and the second mold are formed so as to be separated from each other. It becomes a molding die apparatus that is difficult to remain in the die.

[Brief description of the drawings]

FIG. 1 is a cutaway front view for explaining one embodiment of a resin molding method and a molding die apparatus according to the present invention.

FIG. 2 is a cutaway front view for explaining one embodiment of a resin molding method and a molding die apparatus according to the present invention.

FIG. 3 is a cutaway front view for explaining another embodiment of the resin molding method and the molding die apparatus according to the present invention.

FIG. 4 is a cutaway front view for explaining a conventional resin molding method and a molding die apparatus.

[Explanation of symbols]

 11, 31 First mold 12, 32 Second mold 13, 33 Cavity 14, 34 Transfer passage 15, 35 Eject pin 16, 36 Pot 17, 37 Inject plunger 18 Plunger A Molding resin B Curing Stuff

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI H01L 21/56 H01L 21/56 T // B29L 31:34

Claims (4)

[Claims] 1. A molding resin housed in a pot is extruded by an injection plunger into a cavity formed between a first mold and a second mold when the first mold and the second mold are brought into contact with each other. In the resin molding method in which the first mold and the second mold are separated from each other and then the cured product of the molding resin is taken out and molded, the first mold and the second mold are separated from each other. The method of taking out the cured product of the molding resin is to provide a pair of plungers so as to face the injection plunger with the surface where the first mold and the second mold abut, sandwiching the first mold. After separating the injection plunger and the counter plunger from the cured product of the molding resin while the mold and the second mold are in contact with each other, the first mold and the second mold are separated from each other for molding. A resin molding method, which is a method of taking out a cured product of a resin. 2. An injection plunger and a plunger are separated from a cured product of a molding resin in a state where the first mold and the second mold are in contact with each other, and then the first mold and the second mold are separated. The method of taking out the cured resin of the molding resin by separating the mold is to separate the injection plunger and the counter plunger from the cured resin of the molding resin with the first mold and the second mold in contact with each other. After that, the injection plunger and the plunger are brought into contact with the cured product of the molding resin, and then the first mold and the second mold are separated from each other. The resin molding method according to claim 1, wherein the upper plunger is also separated from the cured product of the molding resin to take out the cured product of the molding resin. 3. A first mold, a second mold disposed so as to be able to contact and separate from the first mold, and a first mold and a second mold when the first mold and the second mold are brought into contact with each other. A cavity formed between the first mold and the second mold when the first mold and the second mold are brought into contact with each other, and a transfer passage for supplying molding resin to the cavity; An eject pin provided to be protrudable into the tee, a pot arranged in the first mold so as to open on a surface where the first mold and the second mold come into contact, and a pot capable of storing molding resin, An injection plunger slidably provided on the inner wall surface of the pot and capable of supplying the molding resin to the cavity via a transfer passage by pressing the molding resin in the pot; Molding metal formed so that the cured product of molding resin can be taken out by separating the mold from the second mold The mold device further includes a pair plunger formed at a portion facing the injection plunger with a surface where the first mold and the second mold abut on each other and slidably provided with the second mold. Before the first mold and the second mold are separated from each other to take out the cured product of the molding resin, the first mold and the second mold are brought into contact with each other from the cured product of the molding resin. A molding die apparatus, wherein the first die and the second die are formed to be separated after the injection plunger and the plunger are separated from each other. 4. The injection plunger and the plunger are separated from the cured product of the molding resin while the first die and the second die are in contact with each other. 4. The molding die apparatus according to claim 3, wherein the first die and the second die are formed so as to abut against a cured product of the molding resin.