	US 12,220,771 B2
	Flux and solder paste
Tomohiro Yamagame, Tokyo (JP); Shuta Akatsuka, Tokyo (JP); Sakie Okada, Tokyo (JP); Keisuke Shinozaki, Tokyo (JP); and Kenta Inoue, Tokyo (JP)
Assigned to SENJU METAL INDUSTRY CO., LTD., Tokyo (JP)
Appl. No. 18/560,992
Filed by SENJU METAL INDUSTRY CO., LTD., Tokyo (JP)
PCT Filed May 27, 2022, PCT No. PCT/JP2022/021679 § 371(c)(1), (2) Date Nov. 15, 2023, PCT Pub. No. WO2022/255234, PCT Pub. Date Dec. 8, 2022.
Claims priority of application No. 2021-091197 (JP), filed on May 31, 2021.
Prior Publication US 2024/0261908 A1, Aug. 8, 2024
Int. Cl. B23K 35/362 (2006.01); B23K 35/02 (2006.01); B23K 35/36 (2006.01)

CPC B23K 35/3613 (2013.01) [B23K 35/025 (2013.01); B23K 35/362 (2013.01)]

9 Claims

1. A flux comprising: a rosin; a rosin amine; p-toluenesulfonic acid; a thixotropic agent; and a solvent,

wherein a content of the rosin is 5% by mass or more and 50% by mass or less with respect to a total amount (100% by mass) of the flux,

a content of the rosin amine is 5% by mass or more and 30% by mass or less with respect to the total amount (100% by mass) of the flux,

a content of the p-toluenesulfonic acid acid is 0.2% by mass or more and 10% by mass or less with respect to the total amount (100% by mass) of the flux,

a ratio (mass ratio) of the content of the rosin amine to the content of the p-toluenesulfonic acid is 3.33 or more and 10 or less.