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:
Jul. 07, 2015
Filed:
Dec. 12, 2007
Yuji Kawamata, Haga-gun, JP;
Takashi Hagiwara, Moka, JP;
Hiroyuki Yamada, Obu, JP;
Kazuyuki Hamamoto, Gamagori, JP;
Yuji Kawamata, Haga-gun, JP;
Takashi Hagiwara, Moka, JP;
Hiroyuki Yamada, Obu, JP;
Kazuyuki Hamamoto, Gamagori, JP;
Senju Metal Industry Co., Ltd., Tokyo, JP;
Denso Corporation, Kariya-shi, JP;
Abstract
A soldering flux which is suitable as a no-clean post flux in flow soldering and which can prevent the formation of whiskers which tends to occur when soldering electronic parts to a printed circuit board using a lead-free solder (such as Sn-3.0Ag-0.5Cu) having a higher Sn content and a higher melting point than the eutectic solder contains, in addition to a rosin as a base resin and an activator, 0.2-4 mass % of at least one compound selected from acid phosphate esters and derivatives thereof. The formation of whiskers can be more effectively prevented by carrying out soldering in a nitrogen atmosphere.