The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 13, 2007
Filed:
May. 12, 2006
Masaaki Yoshikawa, Sagamihara, JP;
Haruo Aoyama, Sagamihara, JP;
Hirotaka Tanaka, Sagamihara, JP;
Nippon Metal Industry Co., Ltd., Tokyo, JP;
Abstract
An Sn—Zn lead-free solder alloy according to the present invention is constructed in a manner such that it is an Sn-based solder alloy indispensably containing 6 to 10 wt % zinc at least and further containing 0.0015 to 0.03 wt % magnesium and 0.0010 to 0.006 wt % aluminum. Upon preservation of solder paste not only under refrigeration but also at a room temperature or higher, the inside of solder particle is protected by the protective magnesium/aluminum oxide film formed on the solder particle surface, and a reaction between zinc and an activator is suppressed, so that preservation stability is improved, and at the elevated temperature during soldering, the solder alloy enters a state where said protective oxide film is easily destroyed, so that good wettability is held.