	US 7,575,150 B2
	Flux composition for solder, solder paste, and method of soldering
Shun Saito, Chita-Gun (Japan); Katsumi Nakasato, Handa (Japan); Yukihiro Kato, Chita-Gun (Japan); and Isao Nakata, Obu (Japan)
Assigned to NOF Corporation, Tokyo (Japan)
Filed on Sep. 24, 2007, as Appl. No. 11/860,395.
Application 11/860395 is a division of application No. 10/491011, abandoned, previously published as PCT/JP02/09946, filed on Sep. 26, 2002.
Claims priority of application No. 2001-295165 (JP), filed on Sep. 26, 2001; application No. 2002-016301 (JP), filed on Jan. 25, 2002; application No. 2002-016302 (JP), filed on Jan. 25, 2002; application No. 2002-093702 (JP), filed on Mar. 29, 2002; and application No. 2002-097483 (JP), filed on Mar. 29, 2002.
Prior Publication US 2008/0073414 A1, Mar. 27, 2008
Int. Cl. B23K 31/02 (2006.01)

U.S. Cl. 228—180.22 [228/207; 228/223; 228/224; 228/248.1]

15 Claims

1. A method of soldering comprising the steps of:

(A) providing a flux composition on an electrode portion of a substrate,

said flux composition comprising at least one compound having at least one blocked carboxyl group selected from the group consisting of:

compound (Y) obtained by reaction of a carboxylic acid anhydride compound and a hydroxy vinyl ether compound, and

compound (Z) obtained by reaction of an acid anhydride and a polyhydric alcohol, followed by addition polymerization with a divinyl ether compound,

wherein said flux composition is free from a compound having two or more reactive functional groups in a molecule capable of forming chemical bonds with carboxyl groups, and

wherein said flux composition is non-curing;

(B) providing a solder bumped electronic component;

(D1) subjecting the substrate with the electronic component obtained in step (C) to reflow for mounting.