Harima Chemicals, Incorporated

Takaaki Anada

Kazuki Ikeda

Hisao Irie

Keigo Obata

Takao Takeuchi

Seishi Kumamoto

Shunsuke Ishikawa

Naoya Inoue

Eiichiro Matsubara

Tetsu Ichitsubo

Toshinori Shima

Syunsuke Ishikawa

A flux for soldering used when soldering is performed to a board subjected to electroless nickel plating, the flux containing resin having film forming ability, activator, and solvent, and further containing metallic salt in an amount of 0.1 to 20% by weight of the total amount of flux. The use of this flux suppresses diffusion of nickel solder in soldering portions, and prevents concentration of phosphorous, thereby improving the bonding strength of soldering.

Flux for soldering, soldering method, and printed circuit board

A flux contains resin having film forming ability, activator, solvent and at least one complex selected from silver complex and copper complex. The flux is used when soldering is performed onto a circuit having electroless nickel plating or further having gold plating on the electroless nickel plating. Allowing a barrier layer of silver or copper to deposit on the surfaces of lands suppresses the diffusion of nickel into the melted solder alloy during soldering, and also prevents phosphorous concentration. This improves the bonding strength of soldering and suppresses the reduction deposition of silver and/or copper to portions other than circuit patterns.

Flux for soldering and circuit board

The present invention is a method to manufacture the SnZnNiCu solder powder through liquid quenching atomizing method, and an atomizing temperature is not less than 500&#xb0; C., in particular, not less than 900&#xb0; C. The raw material metal used as raw material of the solder powder comprises 3 to 12% by weight of Zn, 1.0 to 15% by weight of the sum of Cu and Ni, and Sn and inevitable impurities for the rest, to the total amount of raw material. Thereby, high joint strength is achieved and the SnZnNiCu solder powder which can improve joint reliability of solder joint part is provided.

Method of manufacturing the SnZnNiCu solder powder and the SnZnNiCu solder powder

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Kakogawa, Japan

Takaaki Anada