| abstract |
The present invention uses a flux which contains a rosin, a rosin amine, one or more types of organic sulfonic acid selected from the group consisting of an alkane sulfonic acid, an alkanol sulfonic acid, and an aromatic sulfonic acid, a thixotropic agent, and a solvent, wherein: the rosin content is 5-50 mass%, inclusive, of the total amount (100 mass%) of the flux; the rosin amine content is 5-30 mass%, inclusive, of the total amount (100 mass%) of the flux, the organic sulfonic acid content is 0.2-10 mass%, inclusive, of the total amount (100 mass%) of the flux, and the proportion (mass ratio) of the rosin amine content to the organic sulfonic acid content is 3.33-10, inclusive. |