Abstract: The invention relates to a composition of matter comprising a soldering flux, wherein the flux consists essentially of a combination of a fluxing agent and a solvent, and wherein the fluxing agent comprises a keto acid such as levulinic acid or acetylbutyric acid. The flux may also comprises an ester acid, or comprises a mixture of the keto acid with the ester acid. The solvent comprises a mixture of a tacky solvent with a non-tacky solvent. The invention also relates to a process comprising soldering at least two surfaces together, each of which comprises a metal area to which solder can adhere by employing the following steps in any order: applying solder to at least one of the metal areas, aligning the metal areas so that they are superimposed over one another, heating at least one of the areas to a temperature that comprises at least the melting temperature of the solder. The last step comprises joining the superimposed areas to one another.