Abstract: There is disclosed a conductive ball- or pin-mounted semiconductor packaging substrate having a conductive ball or a conductive pin mounted on a conductive land or through-hole of the semiconductor packaging substrate, wherein the conductive ball or the conductive pin is electrically connected with the conductive land or through-hole through a reflow of a conductive bonding material comprising, at least, a low-melting point lead-free SnBi-based solder and a thermosetting adhesive resin exhibiting fluxing effects.

Abstract: The invention provides a water-soluble preflux that can solve problems with a soldering land array having a narrow spacing in that fused solder is likely to cause soldering bridges with defective soldering, a printed circuit board with its film formed thereon, and a surface treatment process for a metal in that circuit. The water-soluble preflux comprises given two different benzimidazoles compound and an iodine-based compound optionally with an amino acid, etc. The invention provides a printed circuit board with a film of that preflux formed thereon, and a surface treatment process for the metal in that circuit.

Abstract: The invention provides a water-soluble prefluxe that can solve problems with a soldering land array having a narrow spacing in that fused solder is likely to cause soldering bridges with defective soldering, a printed circuit board with its film formed thereon, and a surface treatment process for a metal in that circuit. The water-soluble preflus comprises given two different benzimidazoles compound and an iodine-based compound optionally with an amino acid, etc. The invention provides a printed circuit board with a film of that preflux formed thereon, and a surface treatment process for the metal in that circuit.

Abstract: There is provided a soldering flux for circuit board, which is designed to be employed on an occasion of soldering electronic parts on a circuit board, the soldering flux being free from any organic solvent which may become a cause for contaminating air atmosphere and being capable of providing an excellent insulating property. This soldering flux comprises; a rosin-based modified resin having an acid value of not less than 100, a nondissociative activator formed of a nondissociative halogenide, and an aqueous solvent containing a volatile basic agent. There is also provided a circuit board having a flux film formed from such a soldering flux.