US 11,986,910 B2
Flux and solder paste
Kenta Inoue, Tokyo (JP); Nanako Miyagi, Tokyo (JP); Tomoko Nagai, Tokyo (JP); Kazuyori Takagi, Tokyo (JP); and Akiko Takaki, Tokyo (JP)
Assigned to SENJU METAL INDUSTRY CO., LTD., Tokyo (JP)
Appl. No. 18/036,963
Filed by SENJU METAL INDUSTRY CO., LTD., Tokyo (JP)
PCT Filed Nov. 17, 2021, PCT No. PCT/JP2021/042228
§ 371(c)(1), (2) Date May 15, 2023,
PCT Pub. No. WO2022/107805, PCT Pub. Date May 27, 2022.
Claims priority of application No. 2020-192036 (JP), filed on Nov. 18, 2020; application No. 2020-210556 (JP), filed on Dec. 18, 2020; and application No. 2021-090226 (JP), filed on May 28, 2021.
Prior Publication US 2023/0321768 A1, Oct. 12, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. B23K 35/36 (2006.01); B23K 35/362 (2006.01)
CPC B23K 35/3613 (2013.01) [B23K 35/362 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A flux comprising:
a rosin;
a solvent;
a thixotropic agent; and
an activator,
wherein the thixotropic agent includes a polyamide (PA2),
the PA2 is a condensate of an aliphatic carboxylic acid, a hydroxy group-containing aliphatic carboxylic acid, and an aliphatic amine having 3 to 10 carbon atoms,
the aliphatic carboxylic acid includes an aliphatic dicarboxylic acid having 11 to 20 carbon atoms, and
regarding an endothermic amount calculated from a peak area of a differential scanning calorific curve obtained by differential scanning calorimetry, in the PA2, a ratio of an endothermic amount in a range of 50° C. or higher and 190° C. or lower is 90% or more with respect to a total endothermic amount in a range of 50° C. or higher and 200° C. or lower.