Method of cleaning printed circuit boards using formic acid

摘要: Solder pastes having vehicles including formic acid-soluble organic acids as fluxing agents are described. Fluxing may be compounds of the formula: ##STR1## where R is an electron withdrawing group. In one embodiment, selected from group consisting fluorine, chlorine, bromine, iodine, sulfur, hydroxyl, nitrile, and benzyl. Other suitable formic-acid include, but not limited to, adipic acid, acrylic polyacrylic methacrylic acid polymethacrylic acid. The clean oxides printed circuit boards (PCBs) under assembly then volatilize leaving a residue to cleaned away. cleaning step involves rinsing with No undesired remains indicating that invention effective in boards. Such can used mixed typical solder components, such lead/tin pastes, or applied topically solders, balls; both techniques permit PCBs more easily high quality bonds, little no residue. Malic preferred agent. followed by water rinse.