JPS59226194A - Production of material for electronic parts - Google Patents

Abstract

PURPOSE:To produce a material for electronic parts which is free from ruggedness and uneven brightness by heating directly a metallic blank wire rod on which a tin or tin-lead alloy plating layer is formed while passing said wire rod in a gaseous cooling atmosphere to melt the plating layer then cooling quickly the same imediately thereafter. CONSTITUTION:A metallic wire or rod 1 on which tin or tin-lead alloy plating is formed by electroplating is passed continuously into a reflow jacket 3 maintained in a gaseous cooling atmosphere 2 kept at <=0 deg.C. At the same time the material is directly heated by subjecting the same to resistance heating by direct conduction of electricity or high frequency heating, etc. to melt the plating layer on the surface. The material is passed in a cooling medium 4 underneath the jacket 3 immediately after melting and is thus quickly cooled.

Description

[Detailed Description of the Invention] This invention is for lead wires or connectors of small resistors, capacitors, etc., network resistance lead wires,! −
Regarding the manufacturing method for electronic component materials used as material thorns, in detail, a metal wire or strip (tape) coated with a tin or tin-lead alloy plating layer is made to run in a cooled gas atmosphere at a temperature below 0°C. At the same time, the present invention relates to the mm6 method for materials for electronic components, which is characterized in that the material is directly heated to melt the plating on the surface and then immediately rapidly cooled.

BACKGROUND ART Electronic component materials, particularly metal wires or strips (tape) of Sn or Sn Pb alloy plated wires used as lead wires, usually require a plating thickness of 2 μm or more.

8n or 8n Pb alloy tapes for electronic parts such as connectors are still subjected to reflow treatment for the purpose of preventing line cracking.

Usually, this reflow treatment is carried out by melting the material in the atmosphere or in the air inside the jacket using a method such as resistance heating. However, if this method is applied to a tape (strip) with a plating thickness of 1.5 to 2 μm or more, the plating sound will flow due to the fluidity of the plating surface, resulting in unevenness in the longitudinal direction and uneven gloss, which is undesirable. Therefore, it has been considered impossible to perform reflow treatment on metal tapes with a plating thickness of 1.5 to 2 microns or more.

Furthermore, when a plated metal wire is subjected to flow treatment as described above, it similarly causes uneven gloss in appearance and unevenness in the direction of the handle, so reflow treatment is generally not performed.

In view of the above-mentioned points, the present inventors investigated a reflow treatment for plated metal wires or strips (tape) that does not cause unevenness in the longitudinal direction or uneven gloss, and as a result, they arrived at this invention. .

That is, as shown in the drawings, the method of the present invention is such that a metal wire or striped material 1 coated with a plating layer by electroplating is continuously exposed to a cooling gas atmosphere 2 of 0°C or less or inside a flow jacket 3. During this passage, the plating is coated and the material is directly heated by resistance heating by direct current to the FC material, or high frequency heating, etc. to melt the plating on the surface of the material, and then the lower part of the reflow jacket is immediately cooled. By performing a reflow process in which the material is passed through a medium 4 and rapidly cooled, the purpose is to obtain a material for electronic components that is free from unevenness in the longitudinal direction and uneven gloss.

Therefore, as the material used to obtain the material for electronic parts by the method of this invention, Ou or Ou alloy is electroplated to a thickness of 0.5 to 13μ, preferably 1.5 to 13μ.
The 18μ coating is subjected to reflow treatment.

In the electroplating coating of Sn and SnPb alloy on the above materials, the clear structure is two-layer plating, the inner layer is a SnPb alloy layer with a lower melting point, and the outer layer is an 8n or Sn layer with a higher melting point. Pb
Preferably, it is an alloy.

Next, in the reflow process for materials with 8n or sn Pb alloy plating, a cooling gas is sent as shown in the figure to create an atmosphere of the gas below 0°C, or when the material is passed through a flow jacket, resistance is increased. This is done by melting the plating layer on the surface of the material by direct heating, high-frequency heating, etc., and then immediately passing it through a cooling medium at the bottom of the reflow jacket to rapidly cool the hot-dip plating. , At this time, resistance heating,
Direct heating of the material by high frequency heating or the like is important, and atmospheric heating of the gas inside the jacket does not achieve the purpose.

Therefore, as the cooling gas to be introduced into the reflow jacket, air at a temperature of 0° C. or lower, hydrogen, forming gas, argon, etc. are suitable.

Further, as the cooling medium provided in the lower part of the jacket, mainly water or water containing a surfactant such as polyethylene glyconone is used.

In addition, in the case of flow treatment of the material plated with 8n*8nPb alloy, flux treatment with an organic acid such as V-conic acid may be performed as a pretreatment.

It is also preferable to immerse the film in a sodium phosphate aqueous solution as a discoloration prevention treatment after the reflow process.

Thus, the method for producing materials for electronic components of the present invention, which involves flow processing as described above, can be carried out as a continuous process, and according to this production method, (1) The detailed reason is still unclear. However, since the outermost surface of the material after reflow treatment is cooled (quickly cooled), the fluidity of the plating layer is low, uneven thickness, and unevenness in the longitudinal direction do not occur, resulting in a smooth surface after reflow treatment. In particular, the same results can be obtained even with a thick plating layer of 1.5 to 18 μm.

+2) Apply the same treatment to the wire as for fil')jfD,
It must be possible to do so.

(3) Since reflow treatment has the effect of preventing oxidation, uneven surface gloss does not occur.

You can get benefits such as:

After cutting, the electronic component materials obtained in this manner can be used as lead wires for small resistors, capacitors, etc., or as connector materials, network resistor lead frame materials, and chips by punching, pressing, etc. It can be used as a cap material for resistors, chip capacitors, etc.

The present invention will be explained below with reference to Examples.

Example 1 A phosphor bronze tape of 9.2 mg (l l ffffw) was subjected to normal alkaline electrolytic degreasing and pickling, and then 240 mg of tinned alkanolsulfonate (trade name As-8*) was applied.
f/1 Lead alkanol sulfonate (m product name As-P*) 409
/II Alkanolsulfonic acid (product-f+A8-A*) 15
0 f/1 additive (product name 518Y*) 80
g/II (However, all product names marked with * are manufactured by Ishihara Sangyo Co., Ltd.) 1 OA/cby/5n-to%P in plating bath
b Alloy plating was applied.

The 8n-Pb plated tape thus obtained was
The reflow process was performed at the same speed as the reflow process.

The reflow treatment was performed by standing an iron pipe with a diameter of 5 cIR and a length of 1 m above cooling water, and passing a current of about 300 to 600 A through the power supply roll on the iron pipe and the power supply roll in the cooling water.

The relationship between the plating thickness of the tape after reflow treatment, the atmosphere inside the pipe, the surface smoothness, and the appearance is as shown in Table 1.

Table 1 Example 2 0, 52 Iffφ iron wire was subjected to alkaline electrolytic degreasing in a 200 f/11 sodium hydroxide solution, and further electrolytically pickled in a sulfuric acid bath. 65%8N85%Pb plating or pure AN plating was performed in a borofluoride bath.

Next, this plated iron wire was subjected to a reflow treatment in the same manner as in Example 1.

Table 2 shows the relationship between the plating thickness of the plated iron wire after this reflow treatment, the atmosphere inside the pipe, the surface smoothness, and the appearance.

In addition, in Example 8 in Table 2, plating treatment was performed in B bath after plating in B bath.

[Brief explanation of drawings]

The drawings are explanatory diagrams of the glue flow treatment process of the present invention. l...Material having Sn or sn Pb alloy plating 2...Cooling gas atmosphere 3...Reflow jacket 4...Cooling medium Patent applicant Sumitomo Electric Industries, Ltd. Agent Patent attorney Kazu1) Akira

Claims (3)

[Claims] (1) A method for producing a material for electronic components, characterized by surrounding a material in which a metal wire or strip is coated with tin or tin-lead alloy 9 and surrounded by a cooling gas atmosphere of 0° C. or lower. (2) The method for producing a material for electronic components according to claim 1, wherein tin or tin-lead alloy plating is applied to a thickness of 0.5 to 18 μm. (3) Production of a material for electronic components according to claim 1, wherein the direct heating of the material having a tin or tin-lead alloy plating in a cooling gas atmosphere is resistance heating or high frequency heating. Law.