JP2008254275A - Injection molded article and injection molding method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an injection molded article and its manufacturing method which can obtain miniaturization of the injection molding and prevent splash and dropout of scrap of a glass filler. <P>SOLUTION: The injection molded article is composed of a lead frame 1 and a resin made reflective frame 3 formed in the lead frame 1, the reflective frame 3 has a reflecting surface 3a equipped with an opening part, a gate 3b to be traces of a resin inlet on the back surface side of the reflecting surface 3a is projected, a dent 3c for surrounding the periphery is formed on the gate 3b, and a coating resin 4 for coating the gate 3b is filled in the dent part 3c. Therefore, the injection molded article can be miniaturized and splash and dropout of scrap of the glass filler can be prevented. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an injection-molded article and an injection-molding method, and more particularly to an injection-molded article and an injection-molding method that are effective as a gate mark processing of a gate cutting part.

  As a conventional injection molded product, there is a lead frame manufactured by punching, in which a cup portion is resin-molded by an insert mold (see, for example, Patent Document 1). In addition, as a conventional injection molding method, there is a method in which injection molding is performed using a pin gate, and a recess is provided in a gate cutting portion of an injection molded product so as to accommodate a protrusion of the gate (for example, see Patent Document 2). ).

FIG. 3 is a sectional view showing an LED package as a conventional injection molded product.
In FIG. 3, a cup portion 103 is formed at the center of the resin upper portion 102 formed on the upper surface of the LED lead frame 101 manufactured by punching. A part of the die pad portion 105 and the inner lead portion 106 is exposed at the bottom portion 104 of the cup portion 103.

  There is an LED package in which a resin lower portion 107 is formed on the lower surface of the LED lead frame 101 and a shear mark protrusion 109 remains in the vicinity of the resin injection port 108 (gate port).

FIG. 4 is a cross-sectional view showing a conventional injection molding method. 4 (a) and 4 (b), the lead frame 101 is placed on a molding frame (not shown), and the resin forming the reflection frame 103 is filled from the gate side (part A) (FIG. 4 ( a)). Next, after the resin is cured, the gate 103b is sheared so as not to protrude from the surface of the reflection frame 103, and an injection-molded product having a recess 103c surrounding the periphery is formed on the gate 103b (FIG. 4 ( b)). Some are injection-molded by the method described above.
JP 2006-253344 A (page 4, FIG. 4) JP 04-45911 (2nd page)

  However, in response to the market demands for high miniaturization and high-density mounting, in the conventional injection molded product, it is necessary to reduce the thickness of the injection molded product in order to secure a recess for accommodating the gate shearing portion. However, when the wall thickness is reduced, a through hole is formed, and there is a limit to reducing the wall thickness in an injection molded product such as an electronic component that cannot form the through hole.

  In addition, there is a method of crushing the gate shearing part with a punch or the like to crush the gate shearing part to suppress the protruding amount of the gate shearing part, but glass filler scraps contained in the injected resin are scattered or lump There is a problem of falling off.

  Further, in the conventional method of manufacturing an injection molded product, the depth of the recess is made larger than the height of the remaining gate, so that the depth of the recess is set to 0. 0 mm when the thickness of the injection molded product is 0.2 mm or less. If it is deeper than 1 mm, the fluidity of the resin material becomes extremely poor, and injection molding becomes difficult. Further, when the depth of the recess is 0.1 mm or less, there is a problem that the height of the remaining gate becomes larger than the depth of the recess.

  The present invention is intended to solve the above-described conventional problems, and provides an injection molded product that reduces the size of an injection molded product and prevents scattering of glass filler debris and lumps, and a method for manufacturing the same. For the purpose.

  In order to solve the above-described conventional problems, an injection molded product of the present invention includes a lead frame and a resin reflecting frame formed on the lead frame, and the reflecting frame has a reflecting surface having an opening. A gate which is a trace of the resin injection port is projected on the back side of the reflecting surface, and a recess is formed around the gate, and the recess is filled with a coating resin covering the gate. .

  In addition, the method for manufacturing an injection molded product of the present invention includes a step of placing a lead frame made of a metal plate material on a molding frame, filling a resin forming a reflection frame from the gate side, and a gate that becomes a trace of the resin A step of forming a reflection frame with a recess and surrounding the periphery of the gate and a reflective surface having an opening on the back side of the gate, curing the resin and then shearing the gate to form a reflective frame, It comprises a step of hitting the top of the head and crushing the gate, and a step of filling the recess with a coating resin to cover the gate.

  According to such a configuration, it is possible to reduce the size of the injection-molded product, and to prevent the glass filler waste from being scattered and the lump falling off.

  As described above, according to the manufacturing method for preventing filler falling off around the gate according to the present invention, it is possible to ensure high quality against problems such as glass filler adhesion and dropping even in a package produced from a resin containing glass filler. Can do. In addition, the deterioration of the package can be locally prevented by adding an antioxidant to the resin filling the gate portion. Moreover, the strength of the package can be increased by filling the gate portion with a strength that is inferior to that of other portions because the thickness is thin and the shape is uneven, thereby filling the potting material or the adhesive.

Embodiments of the present invention will be described below with reference to the drawings.
(Embodiment 1)
FIG. 1 is a cross-sectional view of an optical semiconductor device package as an injection molded product according to the present invention.
In FIG. 1, 1 is a lead frame formed by etching or pressing a metal plate material into a predetermined shape, and 2 is a light emitting element mounting portion on which a light emitting element (not shown) is mounted. The lead frame 1 is formed with a reflective frame 3 made of a thermoplastic resin, and the reflective frame 3 has a reflective surface 3a.

  The reflective frame 3 has a protruding gate 3b that is a trace of the injection of the thermoplastic resin, and a recess 3c that surrounds the periphery of the gate 3b. Further, the depression 3c is filled with a coating resin 4 made of an epoxy resin that covers the gate 3b.

  According to such a configuration, even in a package produced from a resin containing a glass filler, high quality can be ensured against problems such as glass filler adhesion and dropping.

  Next, the manufacturing method of the package for optical semiconductor devices of this embodiment is demonstrated using sectional drawing along process flow. FIG. 2 is a cross-sectional view taken along the process flow of the method for manufacturing an optical semiconductor device package according to the present embodiment.

  For example, a lead frame 1 formed by etching or pressing a metal plate material made of copper or a copper alloy is placed on a molding frame (not shown), and the reflection frame 3 is mounted from the gate side (A part). After filling the resin to be formed and curing the resin, the gate 3b is sheared to form the reflective frame 3 having the reflective surface 3a (FIG. 2a).

At this time, the gate 3b which becomes the trace of the filled resin protrudes on the gate side (A portion), and further, the gate 3b is formed with a hollow portion 3c surrounding the periphery.
The lead frame 1 is subjected to functional plating such as silver, gold, or palladium according to the purpose.

  Next, the top of the head is crushed by hitting the gate 3b with a jig or other tool such as a punch (FIG. 2B). At this time, it is preferable that the height of the gate 3b be smashed so that the gate 3b is not struck more than the bottom surface of the recessed portion 3c and is placed inside the uppermost surface of the recessed portion 3c. Further, an air blow or the like may be provided in order to remove glass filler debris and lump contained in the resin filled after crushing.

  Next, the recess 3c is filled with a coating resin 4 made of an epoxy resin to cover the gate 3b (FIG. 2C). At this time, the coating resin 4 is desirable because the epoxy resin is excellent in workability and mechanical / electrical characteristics, but is not limited to the epoxy resin. In particular, an epoxy potting material that has high thermal conductivity, adhesion to a resin package, and high heat resistance and quick curing time is preferable. Further, for the purpose of preventing deterioration of the package and increasing strength, an additive such as an antioxidant may be mixed in the potting material / adhesive.

  According to this Embodiment comprised as mentioned above, while being able to achieve size reduction of an injection molded product, scattering of the waste of a glass filler and drop-off | omission of a lump can be prevented.

  Moreover, in this Embodiment, although resin which comprises the reflective frame 5 was demonstrated as a thermoplastic resin, it is not restricted to this, For example, it is also possible to use a thermosetting resin, a silicone resin, etc. of a synthetic resin. .

  The injection-molded article and the injection-molding method of the present invention are useful for processing a gate mark of a gate cutting part.

Sectional drawing of the package for optical semiconductor devices in Embodiment 1 of this invention Sectional drawing along the process flow of the package for optical semiconductor devices in Embodiment 1 of this invention Cross-sectional view of a conventional injection molded product Sectional view along the process flow of conventional injection molded products

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,101 Lead frame 2 Light emitting element mounting part 3, 103 Reflective frame 3a Reflective surface 3b, 103b Gate 3c Depressed part 4 Coating resin 103c Depressed part

Claims (2)

A lead frame,
It consists of a resin-made reflective frame formed on the lead frame,
The reflective frame has a reflective surface with an opening,
A gate that becomes a trace of the resin injection port is projected on the back side of the reflection surface,
The gate is formed with a recess surrounding the periphery,
An injection-molded product in which the hollow portion is filled with a coating resin that covers the gate. A step of placing a lead frame made of a metal plate material on a molding frame and filling a resin that forms a reflection frame from the gate side;
A recess that protrudes from the gate that becomes the trace of the resin and surrounds the periphery of the gate is formed, and a reflective surface having an opening on the back side of the gate is formed, and after the resin is cured, the gate is sheared and reflected. Forming a frame;
Hitting the top of the gate and crushing the gate;
A method of manufacturing an injection-molded article, comprising: filling the recess with a coating resin to cover the gate.

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