JP2021052121A - Metal strip and method for manufacturing the metal strip - Google Patents

Abstract

To provide a metal strip which has high productivity and an enhanced bonding force with a resin, and a method for manufacturing the metal strip.MEANS FOR SOLVING THE PROBLEM: A metal strip 10 includes a strip-shaped metal base material 12, a plating layer 14 formed on a surface of the metal base material 12, and a rough surface region 16 formed on the metal base material 12. The plating layer 14 is formed on a part of the surface of the metal base material 12. The plating layer 14 is intermittently formed in the length direction of the metal base material 12 by openings 18 of the metal base material 12. A portion of the metal base material 12 on which the plating layer 14 is formed is used as a terminal 22. The rough surface region 16 is a region where the surface roughness of the metal base material 12 is higher than that of a region (an electronic device mounting region 28) other than the rough surface region 16. The rough surface region 16 is a portion of a lead 20 in the metal base material 12, and is formed in a region adjacent to the plating layer 14.SELECTED DRAWING: Figure 1

Description

The present invention relates to a metal strip having a plating layer and a method for producing the metal strip.

Conventionally, a metal strip such as copper has been punched out, and a part of the remaining metal strip has been used as a lead frame for an electronic device. For example, Patent Document 1 below discloses that the peripheral edge of an electronic element in a lead frame is roughened by a laser in order to improve the bonding between the lead frame and the resin.

However, in Patent Document 1, the bonding force between the lead frame and the resin may be weakened in the vicinity of the outer surface of the resin due to environmental factors such as temperature. Further, in order to irradiate a traveling metal strip with a laser in a square shape as in Patent Document 1, it is necessary to irradiate the laser perpendicular to the traveling direction of the metal strip, and the laser irradiation is performed while the metal strip is traveling. Difficult to do and poorly productive.

Japanese Unexamined Patent Publication No. 2018-67600

An object of the present invention is to provide a metal strip having high productivity and an enhanced bonding force with a resin, and a method for producing the metal strip.

The metal strip of the present invention was formed in the boundary region between the strip-shaped metal base material, the plating layer formed in the length direction of the metal base material, and the plating layer in the metal base material. It has a rough surface area.

The method for producing a metal strip of the present invention includes a step of running a strip-shaped metal base material, a step of attaching a masking tape to the running strip-shaped metal base material, and a step of attaching the masking tape of the metal base material. The boundary region between the plating layer and the plating layer in the step of forming the plating layer at a position where the plating layer is not formed, the step of peeling the masking tape from the metal base material on which the plating layer is formed, and the portion of the metal base material where the plating layer is not formed. Is provided with a step of irradiating the surface with a laser to form a rough surface region on the surface of the metal base material.

According to the present invention, by providing a rough surface region in the boundary region between the metal base material and the plating layer, when an electronic element is mounted on a metal strip and sealed with a resin, the rough surface region and the resin can be bonded. Get better.

Since the rough surface region is formed by irradiating the rough surface region while running the metal base material, it is not necessary to stop the metal base material as in the conventional case, and the productivity of the metal strip is good.

It is a perspective view which shows the structure of a metal strip. It is a top view which shows the structure of a metal strip. It is sectional drawing of an electronic device. It is a figure which shows the structure of the metal strip manufacturing apparatus. It is a top view of the metal base material punched out. It is the top view which attached the masking tape to the metal base material. It is a perspective view which formed the plating layer and the rough surface region on the metal base material which was not punched. It is a top view which formed the plating layer and the rough surface region on the metal base material which was not punched.

The metal strip material of the present invention and the method for producing the metal strip material will be described with reference to the drawings.

The metal strip 10 of the present application shown in FIGS. 1 and 2 includes a strip-shaped metal base material 12, a plating layer 14 formed on the surface of the metal base material 12, and a rough surface region 16 formed on the metal base material 12. ..

The metal base material 12 is, for example, a strip (strip) having a width of about 8 to 80 mm and a thickness of about 0.08 to 0.8 mm. The metal base material 12 is made of a copper-based metal. Copper-based metals include pure copper or phosphorus bronze, aluminum bronze, brass, nickel silver, beryllium copper, titanium copper, Corson alloys, white copper, red copper and other copper alloys. Further, the metal base material 12 may be copper-plated on the surface of any metal such as iron or an iron alloy.

The metal base material 12 is punched, and a plurality of openings 18 are formed in the metal base material 12. With this opening 18, the metal substrate 12 includes a lead 20, a terminal 22 connected to the lead 20, and support portions 24a, 24b, 24c for supporting the lead 20 and the terminal 22. The support portions 24a, 24b, and 24c are portions of the metal base material 12 other than the reed 20 and the terminal 22, and the support portions 24a on both sides of the metal base material 12, the support portion 24b at the center of the metal base material 12, and the metal base material 12 It has a support portion 24c that connects the support portions 24a on both sides of the above and the support portion 24b at the center.

The reed 20 includes a mounting area 28 for the electronic element 26 and is sealed with the resin 30 (FIG. 3). There is a space 32 between the leads 20, and the electronic element 26 is mounted on the two leads 20 through the space 32 (FIG. 3). The electronic element 26 may be connected to the lead 20 by various methods such as connection with a conductive adhesive such as silver paste, soldering, or connection with a bonding wire. The terminal 22 is a portion that is not sealed with the resin 30 and is soldered to a circuit such as a printed circuit board. The lead 20 and the terminal 22 face the width direction of the metal base material 12. In this description, the electronic element 26 is a capacitor, a diode, a semiconductor element, or the like in a state before being molded.

The plating layer 14 is formed on a part of the surface of the metal base material 12. Since the metal base material 12 has an opening 18, the plating layer 14 is intermittently formed in the length direction of the metal base material 12. The portion of the metal base material 12 on which the plating layer 14 is formed is used as the terminal 22. In FIGS. 1 and 2, the plating layer 14 is arranged on one surface of the metal base material 12, but the plating layer 14 may be arranged on the other surface, or the plating layer 14 is arranged on both one surface and the other surface. May be. The thickness of the plating layer 14 is about 15 μm or less. Examples of the plating layer 14 include a tin plating layer and a silver plating layer. A plurality of types of plating layers 14 may be laminated.

The rough surface region 16 is a region in which the surface roughness of the metal base material 12 is higher than that of the region other than the rough surface region 16 (the electronic element mounting region 28). The rough surface region 16 is a portion of the reed 20 in the metal base material 12 and is formed in a region adjacent to the plating layer 14. The rough surface region 16 is formed by a plurality of circular depressions. The circular recess is, for example, about 50-100 μm in diameter and about 0.1-5 μm deep. The circular depressions may partially overlap each other.

The end of the rough surface region 16 is preferably formed up to the boundary between the lead 20 and the terminal 22, but the end of the rough surface region 16 should be within a range of 0.5 mm or less from the boundary between the lead 20 and the terminal 22. Just do it.

As shown in FIG. 4, the metal strip 10 manufacturing apparatus 34 includes an apparatus 38 for attaching masking tape 36 to the metal substrate 12, a plating apparatus 40 for forming a plating layer 14 on the metal substrate 12, and a metal substrate 12. A device 42 for peeling the masking tape 38 from the metal base material 12 and a laser device 44 for irradiating the metal base material 12 with the laser L are provided.

The sticking device 38 for sticking the masking tape 36 to the metal base material 12 includes a roll 46 around which the masking tape 36 is wound, and a roll 48 that sandwiches the metal base material 12 and the masking tape 36 together.

As the masking tape 36, for example, a polyester resin or a fluorine resin is used. A silicon-based adhesive layer is provided on the portion of the masking tape 36 to which the metal base material 12 is attached. The thickness of the masking tape 36 is, for example, about 0.05 to 0.1 mm.

While pulling out the masking tape 36 from the roll 46, it synchronizes with the traveling metal base material 12. By sandwiching the metal base material 12 and the masking tape 36 together with the roll 48, the masking tape 36 is attached to the metal base material 12 by the adhesive layer of the masking tape 36.

The plating apparatus 40 forms a plating layer 14 at an exposed position of the metal base material 12. The plating apparatus 40 includes a plating tank 52 in which the plating solution 50 is stored, cathodes 54 upstream and downstream of the plating tank 52, and an anode 56 in the plating solution 50.

The cathode 54 has a roll shape and rotates while being in contact with the metal base material 12. Although the masking tape 36 is attached to the surface of the metal base material 12, the exposed portion of the metal base material 12 comes into contact with the cathode 54 due to vibration during traveling or the like. The anode 56 is a plate-shaped electrode that is not in contact with the metal base material 12 or the like. While the metal base material 12 is running, the metal base material 12 and the plating solution 50 are energized to electrolyze the plating layer 14.

The device 42 for peeling off the masking tape 36 includes a roll 58 for peeling off the masking tape 36 from the metal base material 12 and a roll 60 for winding up the masking tape 58. The masking tape 36 is run toward the roll 60 and wound around the roll 60.

The laser device 44 includes a fiber laser in which the core at the center of the optical fiber is doped with a rare earth element Yb (yttrium), an ultraviolet (UV) laser, a YVO ₄ (neodium: yttrium / vanadium tetroxide) laser, and YAG (yttrium: aluminum). : Garnet) Use a laser device such as a laser. Irradiate the traveling metal base material 12. A high-frequency pulse is applied to the laser apparatus 44 to cause the laser to emit light so that a plurality of laser marks are formed on the metal substrate 12. Two laser devices 44 are provided in order to form the rough surface region 16 on both surfaces of the metal base material 12. The two laser devices 44 are displaced in the traveling direction of the metal base material 12 so that the laser L emitted by one laser device 44 is not irradiated to the other laser device 44.

A laser L absorbing means may be provided on the opposite side of the laser device 44 with respect to the metal base material 12. The metal base material 12 has an opening 18, and when the laser device 44 continuously emits the laser L, the metal base material 12 passes through the opening 18. Therefore, a liquid that absorbs the laser L, a sponge containing the liquid, or the like may be arranged.

The manufacturing apparatus 34 for the metal strip 12 includes a roll 62 around which the metal base material 12 is wound, a roll 64 around which the manufactured metal strip 10 is wound, and a roll 66 which gives a predetermined tension to the metal base material 12. At least, the rotation of the roll 64 that winds up the metal strip 10 causes the metal base material 12 to travel, and the plating layer 14 and the rough surface region 16 are formed during the traveling.

A method for manufacturing the metal strip 10 will be described. (1) A strip-shaped metal base material 12 is prepared. If the metal base material 12 is not a copper-based material, copper plating is applied. As shown in FIG. 5, the metal base material 12 has an opening 18 and a space 32 between the leads 20 formed therein. At the stage of preparing the metal base material 12, the metal base material 12 is washed if necessary. Examples of the cleaning method include cathode electrolytic degreasing and acid immersion. Aqueous sodium hydroxide solution is used for cathode electrolytic degreasing, and sulfuric acid is used for acid immersion.

(2) The masking tape 36 is attached to the metal base material 12. As shown in FIG. 6, a band-shaped masking tape 36 is attached in the length direction of the metal base material 12. The portion to be pasted is other than the portion that becomes the terminal 22. This is because only the portion to be the terminal 22 is exposed to form the plating layer 14.

(3) The plating layer 14 is formed with the masking tape 36 attached to the metal base material 12. The metal base material 12 to which the masking tape 36 is attached is run in the plating solution 50 stored in the plating tank 52. When traveling, the metal base material 12 is brought into contact with the cathode 54, the metal base material 12 and the plating solution 50 are energized, and the plating layer 14 is electrodeposited. The plating layer 14 is formed on an exposed portion of the metal base material 12 without the masking tape 36 attached. Since the exposed portion of the metal base material 12 is intermittently present in the length direction of the metal base material 12 due to the opening 18, the plating layer 14 is intermittently formed in the length direction of the metal base material 12.

(4) Remove the masking tape 36 from the metal base material 12. The metal base material 12 travels straight, while the masking tape 36 travels away from the metal base material 12. Therefore, the masking tape 36 is peeled off from the metal base material 12. The metal base material 12 from which the masking tape 36 has been peeled off is washed and dried.

(5) In the metal base material 12, a rough surface region 16 is formed in a region without the plating layer 14 and in a region adjacent to the plating layer 14. The rough surface region 16 is formed by irradiating a laser. By arranging a plurality of lasers L in the width direction of the metal base material 12 and irradiating them at the same time, the rough surface region 16 is formed while the metal base material 12 is running. The rough surface region 16 is formed intermittently in the length direction of the metal base material 12.

Since the plating layer 14 and the rough surface region 16 are formed while the metal base material 12 is running, the plating layer 14 and the rough surface region 16 are also formed on the support portion 24c.

(6) The metal strip 10 can be manufactured by forming the plating layer 14 and the rough surface region 16, and the metal strip 10 is wound around the roll 64.

In the completed metal strip 10, an electronic element 26 such as a capacitor or a diode is mounted on the lead 20 so as to straddle the space 32, and the electronic element 26 and the lead 20 are resin-sealed (FIG. 3). The resin 30 is provided up to the boundary between the lead 20 and the terminal 22. The region of the reed 20 adjacent to the terminal 22 is a rough surface region 16, and the bondability between the reed 20 and the resin 30 is high. Finally, the electronic device 70 is manufactured by cutting the boundary between the terminal 22 and the support portions 24a on both sides of the metal base material 12.

As described above, in the present application, the region of the lead 20 adjacent to the terminal 22 is set as the rough surface region 16, so that the region 16 has improved bondability with the resin 30. Since the rough surface region 16 is near the outer surface of the resin 30, it is a portion that is easily affected by an external influence such as temperature. However, since the rough surface region 16 enhances the bondability between the reed 20 and the resin 30, it is external. Due to the influence, the resin 30 is hard to come off from the lead 20.

Since the leads 20 and the terminals 22 are oriented in the width direction of the metal base material 12, the rough surface region 16 can be formed in the length direction of the metal base material 12. The rough surface region 16 can be formed while the metal base material 12 is running, and the productivity of the metal strip 10 is good.

Although one embodiment of the present application has been described above, the present application is not limited to the above embodiment. For example, as shown in FIGS. 7 and 8, the plating layer 14 and the rough surface region 16 may be formed on the metal base material 80 that has not been punched, and then punched. A strip-shaped plating layer 14 and a rough surface region 16 are formed in the same direction as the length direction of the metal base material 80.

In addition, the present invention can be carried out in a mode in which various improvements, modifications and changes are made based on the knowledge of those skilled in the art without departing from the gist thereof.

10: Metal strip 12, 80: Metal base material 14: Plating layer 16: Rough surface region 18: Opening 20: Lead 22: Terminals 24a, 24b, 24c: Support portion 26: Electronic element 28: Electronic element mounting area 30 : Resin 32: Space 34: Metal strip manufacturing device 36: Masking tape 38: Masking tape affixing device 40: Plating device 42: Masking tape peeling device 44: Laser device 46, 48, 58, 60, 62, 64, 66: Roll 50: Plating liquid 52: Plating tank 54: Cathode 56: Anosome 70: Electronic device

Claims (6)

A strip of metal substrate and
A plating layer formed so as to face the length direction of the metal base material,
The rough surface region formed in the boundary region between the metal substrate and the plating layer and the rough surface region.
Metal strip with. The metal base material is punched to form leads and terminals connected to the leads.
The metal strip of claim 1, wherein the terminal is a portion having a plating layer. The metal strip material according to claim 2, wherein the plating layer and the rough surface region are intermittently formed so as to face the length direction of the metal base material. The metal strip according to claim 2 or 3, wherein an electronic element mounting region is provided in a portion of the lead other than the rough surface region. The process of running the metal base material of the obi and
The process of attaching masking tape to a traveling strip-shaped metal base material,
A step of forming a plating layer at a position where the masking tape of the metal base material is not attached, and
The process of removing the masking tape from the metal base material on which the plating layer is formed, and
A step of irradiating a boundary region with the plating layer with a laser to form a rough surface region on the surface of the metal substrate in a portion of the metal substrate where the plating layer is not formed.
A method of manufacturing a metal strip equipped with. The method for producing a metal strip according to claim 5, further comprising a step of punching the metal strip to form a lead and a terminal connected to the lead.

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