JP5837010B2 - Resin sealing method for electronic parts - Google Patents

Description

The invention, for example, relates to a resin sealing method for sealing electronic parts such as a capacitor element with a thermosetting resin composition.

Conventionally, for example, electronic parts such as capacitor elements have been sealed with a synthetic resin for the purpose of moisture proofing, insulation, and prevention of deterioration.
As such a resin sealing method, for example, in Patent Document 1, as shown in FIG. 9, first, a case body 110 made of a thermoplastic resin is prepared, and terminal leads 104 and 104 are connected in the case body 110. The capacitor element 102 is put in, and then the liquid thermosetting resin 120 is filled in the gap between the case body 110 and the capacitor element 102 and cured, so that the case body 110 and the capacitor element 102 are cured. And the capacitor element 102 is resin-sealed.

Japanese Patent Laid-Open No. 3-156909

  However, in the capacitor 100 obtained by the conventional resin sealing method as described above, the case body 110 is made of “thermoplastic resin”, whereas the resin filled in the case body 110 is “thermosetting resin”. The materials of the two resins are different.

  Therefore, depending on the combination of the resins, the adhesiveness between the thermoplastic resin and the thermosetting resin is insufficient, and a gap is formed between the two, and moisture penetrates through the gap to deteriorate the internal capacitor element 102. There was a risk of it.

In addition, the time required to cure the thermosetting resin filled in the case main body 110 requires several hours and a considerable time, so that the production efficiency is low.
Furthermore, in the resin sealing method as described above, it is necessary to fill the case main body 110 with the thermosetting resin 120 in a state where the terminal leads 104 and 104 connected to the capacitor element 102 are held and the capacitor element 102 is suspended in the air. However, when the terminal leads 104 and 104 are soft and have a possibility of breakage, the resin sealing method for suspending the capacitor element 102 in this way cannot be employed.

As described above, since the conventional resin sealing method has many problems, a further resin sealing method is actually required.
In view of such circumstances, the present invention can reliably perform resin sealing of electronic components in a short time, and does not need to hold the terminal lead and suspend it even if it has a terminal lead. It aims at providing the resin sealing method of components.

The present invention was invented to solve the problems in the prior art as described above,
The resin sealing method of the electronic component of the present invention is:
A resin sealing method for electronic components,
By pressing and heating a thermosetting resin composition that is solid at room temperature, a bottom surface side holding member that holds the bottom surface side of the electronic component and a top surface side holding member that holds the top surface side of the electronic component. Forming so as not to be completely cured;
Sandwiching the electronic component between the bottom-side holding member and the top-side holding member obtained in the step of molding so as not to be completely cured, and placing the electronic component in an internal space of a mold;
After the step of placing in the inner space of the mold, the mold is closed, and the same material as the thermosetting resin composition forming the bottom surface side holding member and the upper surface side holding member in the inner space of the mold Injecting a molten thermosetting resin composition, and covering the bottom side holding member and the top side holding member sandwiching the electronic component with a molten thermosetting resin composition;
The molten thermosetting resin composition, the bottom-side holding member, and the top-side holding member that are introduced in the coating step are integrated in the mold and completely cured, and are integrated around the electronic component. Forming a thermosetting resin coating layer;
It is characterized by having at least.

With such a method, since the electronic component is sealed only with the thermosetting resin composition, the electronic component can be reliably sealed integrally.
In addition, the bottom side holding member and the top side holding member are prepared in advance, and after sandwiching the electronic component between the bottom side holding member and the top side holding member, the molten thermosetting resin composition is allowed to flow. Therefore, the entire electronic component can be reliably coated with the thermosetting resin composition.

  Further, since the thermosetting resin composition and the melt thermosetting resin composition forming the bottom side holding member and the top side holding member are the same material, they are reliably integrated in the mold, and the electronic component The reliability such as moisture prevention, insulation, and prevention of deterioration in the sealing of the resin can be further enhanced.

Moreover, the resin sealing method of the electronic component of the present invention is as follows.
A resin sealing method for electronic components,
Molding the bottom-side holding member that holds the bottom side of the electronic component so as not to be completely cured by pressurizing and heating a solid thermosetting resin composition at room temperature; and
Placing the electronic component on the bottom-side holding member obtained in the step of molding so as not to be completely cured, and placing the electronic component in an internal space of a mold; and
After the step of disposing in the inner space of the mold, the mold is closed, and the thermosetting resin of the same material as the thermosetting resin composition that forms the bottom surface holding member in the inner space of the mold Flowing the composition and completely covering the electronic component placed on the bottom-side holding member together with the bottom-side holding member with the melt thermosetting resin composition;
The molten thermosetting resin composition and the bottom-side holding member introduced in the coating step are integrated in the mold and completely cured, and the thermosetting resin is integrated around the electronic component. Forming a coating layer;
It is characterized by having at least.

With such a method, since the electronic component is sealed only with the thermosetting resin composition, the electronic component can be reliably sealed integrally.
In addition, since the bottom-side holding member is prepared in advance and the molten thermosetting resin composition is allowed to flow after the electronic component is placed on the bottom-side holding member, the entire electronic component is surely secured. It can be coated with a thermosetting resin composition.

  Furthermore, since the thermosetting resin composition and the melt thermosetting resin composition that form the bottom-side holding member are the same material, both are reliably integrated in the mold, and moisture-proofing in sealing of electronic components, Reliability such as insulation and prevention of deterioration can be further improved.

Moreover, the resin sealing method of the electronic component of the present invention is as follows.
The melting temperature of the molten thermosetting resin composition is in the range of 50 to 130 ° C.
If it is in the range of such melting temperature, there is no possibility that an electronic component may be broken by heat, and the resin sealing of an electronic component can be performed reliably with a high yield.

Moreover, the resin sealing method of the electronic component of the present invention is as follows.
The thermosetting resin contained in the molten thermosetting resin composition and the thermosetting resin composition that is solid at room temperature is an epoxy resin.
With such a thermosetting resin composition, it is possible to improve reliability such as moisture proofing, insulation and prevention of deterioration particularly in sealing of electronic parts.

Moreover, the resin sealing method of the electronic component of the present invention is as follows.
The thickness of the bottom surface of the bottom surface holding member is positioned substantially at the center of the sealed thermosetting resin composition when the electronic component is sealed with the thermosetting resin composition in the mold. The inner space of the mold is set according to the height of the electronic component and the height of the electronic component.

  In this way, if the thickness of the bottom surface of the bottom surface holding member is set, the layer thickness of the thermosetting resin composition covering the electronic component can be made substantially the same in at least the height direction. Without being biased to one side, it can be surely positioned substantially in the center and the product quality can be kept constant.

Moreover, the resin sealing method of the electronic component of the present invention is as follows.
In the step of molding so as not to be completely cured by pressurizing and heating the solid thermosetting resin composition at room temperature,
At least the pressure applied to the solid thermosetting resin composition at normal temperature is in the range of 5 to 300 MPa, and the temperature is in the range of 20 to 120 ° C.

  If it is in the range of such pressurization pressure and heating temperature, a powdery thermosetting resin composition will not be hardened completely. That is, since the powdery thermosetting resin composition is molded in an incompletely cured state, the subsequent integration with the molten thermosetting resin composition is ensured, and the electronic component is reliably resinated. It can be sealed.

Moreover, the resin sealing method of the electronic component of the present invention is as follows.
The electronic component is a capacitor element.
In this way, since the moisture resistance, insulation, prevention of deterioration and the like are required with high accuracy in the case of the capacitor element, the resin sealing method of the present invention can be suitably used.

According to the present invention, by using a solid thermosetting resin composition in an incompletely cured state and a molten thermosetting resin composition in the same material as the thermosetting resin composition and in a molten state, The resin of the electronic component that can be reliably sealed in a short time, and does not need to hold the terminal lead and hang it even if it has a terminal lead. A sealing method can be provided.

FIG. 1 is a schematic view of a resin-encapsulated electronic component obtained by encapsulating an electronic component by the resin sealing method of the present invention. FIG. 2 is a process diagram illustrating a manufacturing process of the bottom-side holding member. FIG. 3 is a process diagram showing a manufacturing process of the upper surface side holding member. FIG. 4 is a process diagram showing a resin sealing process in the first embodiment of the resin-encapsulated electronic component. FIG. 5 is a process diagram showing a resin sealing process in the first embodiment of the resin-encapsulated electronic component. FIG. 6 is a process diagram showing a resin sealing process in the second embodiment of the resin-encapsulated electronic component. FIG. 7 is a process diagram showing a resin sealing process in the second embodiment of the resin-encapsulated electronic component. FIG. 8 is a schematic view showing another form of the bottom side holding member. FIG. 9 is a schematic view of a capacitor formed by sealing a capacitor element by a conventional resin sealing method.

Hereinafter, embodiments of the present invention will be described in more detail based on the drawings.
The present invention is a resin sealing method for sealing an electronic component such as a capacitor element with a thermosetting resin composition.

<Resin encapsulated electronic component 10>
As shown in FIG. 1A, a resin-encapsulated electronic component 10 formed by encapsulating an electronic component by the resin-encapsulating method of the present invention is a substantially rectangular parallelepiped, and the internal structure thereof is shown in FIG. 1A is a cross-sectional view taken along line AA in FIG. 1A, and the thermosetting resin coating layer 14 covers the internal electronic component 12 without a gap.

At this time, the thermosetting resin coating layer 14 covering the periphery of the electronic component 12 is provided with a similar thickness at least above and below the electronic component 12.
The resin-encapsulated electronic component 10 is not limited to a substantially rectangular parallelepiped, and may take any form. However, since it is assumed that the resin-encapsulated electronic component 10 is fixed to a substrate or the like, it is preferable that the resin-encapsulated electronic component 10 has a good stability as shown in FIG.

With this structure, the internal electronic component 12 can be moisture-proof, insulated, and prevented from deterioration by the thermosetting resin coating layer 14.
The electronic component 12 is not particularly limited, and examples thereof include a capacitor element, a coil, and a circuit board. In particular, this structure is suitable because the capacitor element particularly requires the above-described effects such as moisture prevention, insulation, and prevention of deterioration.

When the electronic component 12 is a capacitor element, a terminal lead is usually connected to the capacitor element, but the connection position of the terminal lead is various, and its form is widely known. It is not specifically shown in the book.
Next, a specific resin sealing method of the electronic component 12 in the resin-encapsulated electronic component 10 thus configured will be described.

<Resin sealing method of electronic component 12>
First, a method for manufacturing the bottom surface side holding member 30a that holds the bottom surface side of the electronic component 12 will be described.

  As shown in FIG. 2A, a thermosetting resin composition 30 that is solid at room temperature is accommodated in molds 20 and 22 prepared in advance. The molds 20 and 22 are formed by attaching the inverted shape of the bottom surface side holding member 30a. The term “solid at normal temperature” means that it can be handled as a solid at 20 ° C. and is not liquid. A thermosetting resin composition that is solid at room temperature usually has a granular shape such as a pellet shape, a tablet shape, a flake shape, or a powder shape from the viewpoint of ease of handling and the like.

  Next, as shown in FIG. 2 (b), the molds 20 and 22 are closed, and the solid thermosetting resin composition 30 is pressurized and heated at the normal temperature inside. At this time, the pressure and temperature applied to the powdery thermosetting resin composition 30 are usually in the range of 5 to 300 MPa, preferably in the range of 5 to 200 MPa, and the temperature is usually 40 to 50 ° C. Within the range, preferably within the range of 45-50 ° C.

By setting the pressure and temperature within such a range, the thermosetting resin composition 30 can be molded so as not to be completely cured.
And as shown in FIG.2 (c), the bottom face side holding member 30a which consists of the thermosetting resin composition 30 shape | molded so that it may not harden | cure completely is obtained by opening the metal mold | dies 20 and 22.

Next, the upper surface side holding member 50a that holds the upper surface side of the electronic component 12 is manufactured in the same manner as the bottom surface side holding member 30a.
First, as shown in FIG. 3A, a thermosetting resin composition 50 that is solid at room temperature is accommodated in molds 40 and 42 prepared in advance. The molds 40 and 42 are formed by inverting the upper surface side holding member 50a.

  Next, as shown in FIG. 3B, the molds 40 and 42 are closed, and the solid thermosetting resin composition 50 is pressurized and heated at the normal temperature inside. At this time, the pressure and temperature applied to the thermosetting resin composition 50 are usually in the range of 5 to 300 MPa, preferably in the range of 5 to 200 MPa, and the temperature is usually in the range of 20 to 120 ° C. Preferably it exists in the range of 40-50 degreeC.

By setting the pressure and temperature within such a range, the thermosetting resin composition 50 can be molded so as not to be completely cured.
In the present specification, the “not completely cured” state means that the thermosetting resin contained in the thermosetting resin composition is not completely cured. It refers to a state where it can be molded integrally with the melt thermosetting resin composition.

  And as shown in FIG.3 (c), by opening the metal mold | die 40,42, the upper surface side holding member 50a which consists of the thermosetting resin composition 50 shape | molded so that it may not harden | cure completely is obtained.

Here, it is preferable that the thermosetting resin compositions 30 and 50 used when molding the bottom surface holding member 30a and the top surface holding member 50a are the same.
The thermosetting resin compositions 30 and 50 are, for example, a curing agent, a filler, and, if necessary, a curing accelerator and other additives added to the thermosetting resin and mixed, and this is kneaded with a heating roll. Then, it can be manufactured by cooling and pulverizing. Moreover, after cooling, it may be made into a desired shape and further subjected to a treatment such as classification as necessary.

  Examples of the thermosetting resin include epoxy resins, thermosetting urethane resins, diallyl phthalate resins, alkyd resins, unsaturated polyester resins, phenol resins, urea resins, melamine resins, and benzoguanamine resins. Among these thermosetting resins, epoxy resins are preferable from the viewpoint of sealing performance of electronic components.

  Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, orthocresol novolak type epoxy resin, polyfunctional type epoxy resin, and the like. Glycidyl ether type epoxy resin, naphthalene skeleton-containing epoxy resin, naphthalene skeleton-containing novolak type epoxy resin, biphenyl skeleton-containing epoxy resin, dicyclopentadiene skeleton-containing epoxy resin, alicyclic epoxy resin, and the like. Among these epoxy resins, orthocresol novolac type epoxy resins are preferable from the viewpoint of moldability and the like.

  In addition, since the thermosetting resin composition used in the present invention is solid at normal temperature, the epoxy resin may be solid at normal temperature, typically in a state where crystals are formed at normal temperature. On the other hand, in the present invention, the thermosetting resin composition is preferably solid at room temperature.

  As the curing agent, when the thermosetting resin is an epoxy resin, for example, amines such as diaminodiphenylmethane, diaminodiphenylsulfone, m-phenylenediamine; phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, anhydrous Examples thereof include acid anhydrides such as tetrahydrophthalic acid; phenol resins such as phenol novolac resin and aralkylphenol resin. Among these curing agents, phenol novolac resins are preferable from the viewpoints of moldability, heat resistance, and moisture resistance.

The chemical equivalent ratio of the curing agent to the epoxy resin (curing agent / epoxy resin) is preferably in the range of 0.5 to 1.5, and more preferably in the range of 0.7 to 1.2.
Examples of the curing accelerator include 2-ethyl-4-methylimidazole, 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2. -Phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2 -Undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2'-methylimidazolyl- (1 ')]-ethyl-s-triazine, 2 , 4-Diamino-6- [2'-undecylimidazoli -(1 ')]-ethyl-s-triazine, 2,4-diamino-6- [2'-ethyl-4'-methylimidazolyl- (1')]-ethyl-s-triazine, 2,4-diamino -6- [2'-methylimidazolyl- (1 ')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl -4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline, 2-Phenylimidazoline, 2,4-diamino-6-vinyl-s-triazine, 2,4-diamino-6-vinyl-s-triazine isocyanuric acid adduct Imidazole compounds such as 2,4-diamino-6-methacryloyloxyethyl-s-triazine, epoxy-imidazole adduct, epoxy-phenol-borate ester compound; 3- (3,4-dichlorophenyl) -1,1- Urea compounds such as dimethylurea; 1,8-diaza-bicyclo [5,4,0] undecene-7, cyclo (5,4,0) undecene-7, triethylenediamine, tri-2,4,6-dimethylamino Tertiary amines such as methylphenol; phosphorus compounds such as triphenylphosphine, tetraphenylphosphonium tetraphenylborate, tetra-n-butylphosphonium-o, o-diethylphosphorodithioate; quaternary ammonium salts, organometallic salts, etc. Is mentioned. Among these curing accelerators, an imidazole compound is preferable from the viewpoint of curing speed.

The curing accelerator is preferably blended in the range of 0.1 to 20 parts by weight, more preferably 0.5 to 10 parts by weight with respect to 100 parts by weight of the epoxy resin.
Examples of the filler include inorganic fillers such as silica, alumina, zirconia, titanium oxide, calcium carbonate, aluminum nitride, magnesium hydroxide, talc, mica, and clay; and organic fillers such as rubber and nylon. .

The filler is preferably blended in the range of 100 to 1000 parts by weight, more preferably 300 to 1000 parts by weight, with respect to 100 parts by weight of the epoxy resin.
Examples of other additives include a colorant, a release agent, and a coupling agent.

  The bottom-side holding member 30a and the top-side holding member 50a manufactured in this way may be in the same form, but depending on the position of the gate in the inner space of the molds 60 and 62, etc. It is preferable to adjust the thickness t1 of the member 30a and the thickness t2 of the upper surface side holding member 50a.

  The reason for this is that in the resin sealing step described later, the electronic component 12 is sandwiched between the bottom surface side holding member 30a and the top surface side holding member 50a, and the periphery thereof is further covered with the melt thermosetting resin composition 70. Therefore, when the resin-encapsulated electronic component 10 is completed, the thickness of the thermosetting resin coating layer 14 covering the electronic component 12 is made equal on the upper and lower sides of the electronic component 12.

Next, a resin sealing method of the electronic component 12 using the bottom surface side holding member 30a and the top surface side holding member 50a obtained in the above process will be described.
As shown in FIG. 4A, the electronic component 12 is sandwiched between the bottom surface side holding member 30a and the top surface side holding member 50a.

  As shown in FIG. 4B, this is disposed in the internal space 64 of the molds 60 and 62, and the molds 60 and 62 are closed as shown in FIG. 4C. At this time, the inner space 64 of the molds 60 and 62 is preferably set to be slightly larger than the bottom surface side holding member 30a and the top surface side holding member 50a with the electronic component 12 interposed therebetween.

  The gap widths t3 and t4 between the left and right end portions of the internal space 64 and the left and right end portions of the bottom surface side holding member 30a and the top surface side holding member 50a sandwiching the electronic component 12 are preferably 0.5 to 2.0 mm. Is preferably set to about 0.5 to 1.0 mm.

  If the left and right gap widths t3 and t4 are set in this way, the movement of the bottom surface side holding member 30a and the top surface side holding member 50a sandwiching the electronic component 12 in the internal space 64 of the molds 60 and 62 is greatly limited. Therefore, position fixing in the internal space 64 can be substantially eliminated.

  The gap width t5 between the upper end of the internal space 64 and the upper end of the bottom holding member 30a and the top holding member 50a sandwiching the electronic component 12 is 0.5 to 2.0 mm, preferably 0. It is preferable to make it about 5-1.0 mm.

  Thus, if the gap widths t3, t4, and t5 are set as shown in FIG. 4C, the fluidity inside the molds 60 and 62 of the later-described molten thermosetting resin composition 70 can be improved. In addition, since the bottom surface side holding member 30a and the top surface side holding member 50a sandwiching the electronic component 12 are greatly restricted in movement of the molds 60 and 62 in the internal space 64, the position in the internal space 64 can be fixed. It can be substantially unnecessary.

  The height h1 of the internal space 64 may be set according to the total thickness of the height h2 of the electronic component 12, the thickness t1 of the bottom surface holding member 30a, and the thickness t2 of the top surface holding member 50a. What is necessary is just to change a design suitably according to the form and magnitude | size of the components 12. FIG.

  Next, as shown in FIG. 5 (a), the bottom-side holding member 30a and the top-side holding member in which the molten thermosetting resin composition 70 is caused to flow into the clamped dies 60 and 62 and the electronic component 12 is sandwiched therebetween. 50 a is coated with the melt thermosetting resin composition 70.

  The temperature and pressure when the molten thermosetting resin composition 70 is allowed to flow into the molds 60 and 62 are usually in the range of 100 to 150 ° C., preferably in the range of 110 to 130 ° C., and the pressure is Usually, it is in the range of 10 MPa to 50 MPa, preferably in the range of 10 MPa to 20 MPa.

Here, the molten thermosetting resin composition 70 that has flowed into the molds 60 and 62 is made of the same material as the thermosetting resin compositions 30 and 50 that are solid at room temperature.
And as shown in FIG.5 (b), the bottom surface side holding member 30a, the upper surface side holding member 50a, and the melt | fusion thermosetting resin composition 70 are carried out by the temperature and inflow pressure which are added to the melt thermosetting resin composition 70. It is first integrated and then fully cured.

Thereafter, when the molds 60 and 62 are opened as shown in FIG. 5C, the resin-encapsulated electronic component 10 in which the electronic component 12 is completely covered with the thermosetting resin coating layer 14 is obtained.
The time required for obtaining the resin-encapsulated electronic component 10 after setting the sandwiched article sandwiching the electronic component 12 between the bottom-side holding member 30a and the top-side holding member 50a in the molds 60 and 62, that is, the cycle time Is about 3 to 10 minutes.

  Therefore, the resin sealing method of the present invention requires only a short time compared to the resin sealing method that takes several hours to cure the resin sealing, as in the prior art described in the background art section, and dramatically The manufacturing cycle can be improved.

  In addition, although resin compositions having different properties of solid and molten are used, since they are thermosetting resin compositions of the same material, both can be reliably integrated, and resin sealing of the electronic component 12 can be achieved. It can be done reliably.

Next, a method different from the resin sealing method described above will be described.
The resin sealing method shown in FIGS. 6A to 7C is basically the same as the resin sealing method shown in FIGS. 4A to 5C, and therefore has the same configuration. The same reference numerals are assigned to the members, and detailed descriptions thereof are omitted.

The resin sealing method shown in FIGS. 6A to 7C is different from the resin sealing method described above in that only the bottom surface side holding member 30a is used and the top surface side holding member 50a is not used. Yes.
In this resin sealing method, first, as shown in FIG. 6 (a), the electronic component 12 is placed on the bottom-side holding member 30a, and this is performed as shown in FIG. 6 (b). It arrange | positions in the interior space 64 of 60 and 62, and the metal mold | dies 60 and 62 are closed as shown in FIG.6 (c).

  7A, the molten thermosetting resin composition 70 is caused to flow into the internal space 64 of the molds 60 and 62, and the bottom-side holding member 30a and the electronic component 12 are fused with the molten thermosetting resin. Coat with composition 70.

  The temperature and pressure when the molten thermosetting resin composition 70 is allowed to flow into the molds 60 and 62 are usually in the range of 100 to 150 ° C., preferably in the range of 110 to 130 ° C., and the pressure is Usually, it is in the range of 10 MPa to 50 MPa, preferably in the range of 10 MPa to 20 MPa.

  Then, as shown in FIG. 7 (b), the bottom-side holding member 30a and the molten thermosetting resin composition 70 are first integrated by the temperature and pressure applied to the molten thermosetting resin composition 70, and then Fully cured.

Further, when the molds 60 and 62 are opened as shown in FIG. 7C, the resin-encapsulated electronic component 10 in which the electronic component 12 is completely covered with the thermosetting resin coating layer 14 is obtained.
As described above, the resin sealing method of the electronic component 12 of the present invention and the resin-encapsulated electronic component 10 formed by sealing the electronic component 12 by this resin sealing method have been described, but the present invention is limited to the above-described method. However, various modifications are possible without departing from the scope of the present invention.

  For example, instead of the above-described bottom surface side holding member 30a, the bottom surface side holding member 30b shown in FIG. 8A may be configured to only support the bottom surface of the electronic component 12, or as shown in FIG. 8B. It is good also as a form which covers to the upper surface vicinity of the electronic component 12 like the bottom face side holding member 30c.

  Further, in the present specification, when the molten thermosetting resin composition 70 is caused to flow into the molds 60 and 62, the gate position for allowing the molten resin to flow into the molds 60 and 62 from above is described. There is no particular limitation, and for example, a side gate or a plurality of gates may be used.

  The molds 60 and 62 may be in the form of taking one resin-encapsulated electronic component 10 or taking many pieces, and it is obvious that the design can be appropriately changed according to the production cycle.

  Further, when the electronic component 12 is provided with a lead terminal (not shown), a lead terminal groove (not shown) is formed in the mold 60, 62, and the mold 60, 62 is attached to the mold 60, 62. When closed, the lead terminals (not shown) may be sandwiched between the upper and lower dies 60 and 62 without any gap, and a technique that can be generally known by those skilled in the art may be employed.

  The apparatus used in the resin sealing method of the present invention is a resin sealing with the resin composition of the electronic component by performing transfer molding and injection molding with a transfer molding machine, injection molding machine, etc. using the above-mentioned mold. Is possible.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.

[Example 1]
The resin sealing of the capacitor element was performed using the resin sealing method of the present invention shown in FIGS. 4 (a) to 5 (c).
First, as shown in FIG. 4A, the capacitor element was sandwiched between a bottom surface holding member 30a and a top surface holding member 50a prepared in advance to form a sandwiching body. The capacitor element is formed by connecting two lead terminals at one end, and a groove for a lead terminal is formed in the bottom-side holding member 30a and the top-side holding member 50a. Is projected outward from the bottom surface side holding member 30a and the top surface side holding member 50a.

The bottom side holding member 30a and the top side holding member 50a are formed by pressurizing a powdered thermosetting resin composition to 180 MPa and heating to 45 ° C. in a mold. It is not cured.
Table 1 shows the composition of the thermosetting resin composition that is solid at room temperature.

Further, the thickness t1 of the bottom surface side holding member 30a was 9 mm, the thickness t2 of the top surface side holding member 50a was 7 mm, and the height h2 of the capacitor element was 11.5 mm.
Next, the sandwiched body was placed in the internal space 64 of the molds 60 and 62 as shown in FIG. 4B, and the molds 60 and 62 were closed as shown in FIG. 4C. Relief grooves for lead terminals are formed in the molds 60 and 62 so that the lead terminals are not crushed by the molds 60 and 62 when the molds 60 and 62 are closed.

  The height h1 of the inner space 64 of the molds 60 and 62 is 18 mm, the left gap width between the inner space 64 and the sandwiching body is 0.5 mm, the right gap width between the inner space 64 and the sandwiching body is 0.5 mm, The upper gap width between the internal space 64 and the sandwiching body was 0.5 mm.

  In this state, the 90 ° C. molten thermosetting resin composition 70 was caused to flow into the internal space 64 of the molds 60 and 62 heated to 120 ° C. as shown in FIG. The composition of the molten thermosetting resin composition 70 is the same as the powdery thermosetting resin composition obtained by molding the bottom surface side holding member 30a and the top surface side holding member 50a.

  Next, as shown in FIG. 5B, the molten thermosetting resin composition 70, the bottom surface side holding member 30a and the top surface side holding member 50a in the molds 60 and 62 are melted and integrated, and then completely Cured.

Then, as shown in FIG. 5C, by opening the molds 60 and 62, a capacitor in which the capacitor element was completely covered with the thermosetting resin coating layer 14 was obtained.
The capacitor obtained by the resin sealing method of this example was left in a space at a temperature of 23 ° C. and a humidity of 50% for 24 hours, and then a continuity test of this capacitor was performed. As a result, reliable conduction was confirmed.
It was also confirmed that there was no evidence of water immersion and no deterioration of the capacitor.

[Example 2]
Resin sealing of the capacitor element was performed using the resin sealing method of the present invention shown in FIGS. 6 (a) to 7 (c).

  First, as shown to Fig.6 (a), the capacitor | condenser element was mounted on the bottom face side holding member 30a prepared previously, and the mounting body was formed. The capacitor element has two lead terminals connected to one end.

The bottom-side holding member 30a is formed by pressing a powdery thermosetting resin composition to 180 MPa and heating to 45 ° C. in a mold, and is not completely cured. is there.
The composition of the thermosetting resin composition that is solid at room temperature is shown in Table 2.

Furthermore, the thickness t1 of the bottom-side holding member 30a was 9 mm, and the height h2 of the capacitor element was 11.5 mm.
Next, the mounting body was placed in the internal space 64 of the molds 60 and 62 as shown in FIG. 6B, and the molds 60 and 62 were closed as shown in FIG. 6C. Relief grooves for lead terminals are formed in the molds 60 and 62 so that the lead terminals are not crushed by the molds 60 and 62 when the molds 60 and 62 are closed.

  The height h1 of the inner space 64 of the molds 60 and 62 is 18 mm, the left gap width between the inner space 64 and the mounting body is 0.5 mm, and the right gap width between the inner space 64 and the mounting body is 0. The gap width of the upper part of 5 mm and the internal space 64 and the mounting body was 0.5 mm.

  In this state, the 90 ° C. molten thermosetting resin composition 70 was caused to flow into the internal space 64 of the molds 60 and 62 heated to 120 ° C. as shown in FIG. The composition of the molten thermosetting resin composition 70 is the same as the powdery thermosetting resin composition obtained by molding the bottom-side holding member 30a.

Next, as shown in FIG. 7B, the melt thermosetting resin composition 70 and the bottom-side holding member 30a in the molds 60 and 62 were melted and integrated, and then completely cured.
And as shown in FIG.7 (c), the capacitor | condenser element completely covered with the thermosetting resin coating layer 14 was obtained by opening the metal mold | die 60,62.

The capacitor obtained by the resin sealing method of this example was left in a space at a temperature of 23 ° C. and a humidity of 50% for 24 hours, and then a continuity test of this capacitor was performed. As a result, reliable conduction was confirmed.
It was also confirmed that there was no evidence of water immersion and no deterioration of the capacitor.

[Comparative Example 1]
In the resin sealing method shown in the first embodiment, as shown in FIG. 4A, the capacitor element is sandwiched between the bottom-side holding member 30a and the top-side holding member 50a prepared in advance to form a sandwiched body. Then, it is arranged in the inner space 64 of the molds 60 and 62 heated to 120 ° C., and the molten thermosetting resin composition 70 at 90 ° C. is allowed to flow, but a sandwich is formed and heated to 120 ° C. After being placed in the inner space 64 of the molds 60 and 62, it was confirmed whether or not the capacitor element could be sealed without allowing the molten thermosetting resin composition 70 to flow.

  As a result, since the sandwiching body is only disposed in the internal space 64 of the molds 60 and 62, when the molds 60 and 62 are opened, the bottom surface side holding member 30a and the top surface side holding member 50a are melted and integrated to be cured. However, a capacitor covered with a thermosetting resin coating layer with voids was obtained.

The capacitor obtained by the resin sealing method of this comparative example was left in a space at a temperature of 23 ° C. and a humidity of 50% for 24 hours, and then a continuity test of this capacitor was performed. It was.
In addition, traces of water immersion were confirmed in some of the capacitors.

DESCRIPTION OF SYMBOLS 10 ... Resin sealing electronic component 12 ... Electronic component 14 ... Thermosetting resin coating layer 20 ... Mold 22 ... Mold 30 ... Powdery thermosetting resin composition 30a ... Bottom side holding member 30b ... Bottom side holding member 30c ... Bottom side holding member 40 ... Mold 42 ... Mold 50 ... Powdered thermosetting resin composition 50a ... Side holding member 60 ... Mold 62 ... Mold 64 ... Internal space 70 ... Melt thermosetting resin composition t1 ·· Thickness of bottom side holding member t2 ·· Thickness of top side holding member t3 ·· Left gap width t4 ·· Right gap width t5 ·· Upper gap width h1 ·· Inner space height h2 ·· Electronic component height 100 ··· Capacitor 102 ··· Capacitor element 104 · ..Terminal lead 110 ... Case body 120 ... thermosetting resin

Claims (7)

A resin sealing method for electronic components,
By pressing and heating a thermosetting resin composition that is solid at room temperature, a bottom surface side holding member that holds the bottom surface side of the electronic component and a top surface side holding member that holds the top surface side of the electronic component. Forming so as not to be completely cured;
Sandwiching the electronic component between the bottom-side holding member and the top-side holding member obtained in the step of molding so as not to be completely cured, and placing the electronic component in an internal space of a mold;
After the step of placing in the inner space of the mold, the mold is closed, and the same material as the thermosetting resin composition forming the bottom surface side holding member and the upper surface side holding member in the inner space of the mold Injecting a molten thermosetting resin composition, and covering the bottom side holding member and the top side holding member sandwiching the electronic component with a molten thermosetting resin composition;
The molten thermosetting resin composition, the bottom-side holding member, and the top-side holding member that are introduced in the coating step are integrated in the mold and completely cured, and are integrated around the electronic component. Forming a thermosetting resin coating layer;
A resin sealing method for electronic parts, comprising: A resin sealing method for electronic components,
Molding the bottom-side holding member that holds the bottom side of the electronic component so as not to be completely cured by pressurizing and heating a solid thermosetting resin composition at room temperature; and
Placing the electronic component on the bottom-side holding member obtained in the step of molding so as not to be completely cured, and placing the electronic component in an internal space of a mold; and
After the step of disposing in the inner space of the mold, the mold is closed, and the thermosetting resin of the same material as the thermosetting resin composition that forms the bottom surface holding member in the inner space of the mold Flowing the composition and completely covering the electronic component placed on the bottom-side holding member together with the bottom-side holding member with the melt thermosetting resin composition;
The molten thermosetting resin composition and the bottom-side holding member introduced in the coating step are integrated in the mold and completely cured, and the thermosetting resin is integrated around the electronic component. Forming a coating layer;
A resin sealing method for electronic parts, comprising:   3. The resin sealing method for an electronic component according to claim 1, wherein a melting temperature of the molten thermosetting resin composition is in a range of 50 to 130 ° C. 4.   The resin for electronic parts according to claim 1, wherein the thermosetting resin contained in the molten thermosetting resin and the thermosetting resin composition that is solid at room temperature is an epoxy resin. Sealing method.   The thickness of the bottom surface of the bottom surface holding member is positioned substantially at the center of the sealed thermosetting resin composition when the electronic component is sealed with the thermosetting resin composition in the mold. 5. The resin sealing method for an electronic component according to claim 1, wherein the method is set according to a height of an internal space of the mold and a height of the electronic component. In the step of molding so as not to be completely cured by pressurizing and heating the solid thermosetting resin composition at room temperature,
The pressure applied to the thermosetting resin composition that is solid at least at the normal temperature is in the range of 5 to 300 MPa, and the temperature is in the range of 20 to 120 ° C. Resin sealing method for electronic parts.   The resin sealing method for an electronic component according to claim 1, wherein the electronic component is a capacitor element.

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