Patent GB-684081-A (GB)
Title: Improvements in or relating to solder flux compositions
IPC: B23K35/36
Filed: 1947-07-28
Abstract: Addition compounds are prepared by reacting an organic compound containing amino and alcoholic hydroxyl groups and at least two carbon atoms with a boro-fluoridic compound such as BF3, hydrofluoboric acid and heavy metal fluoborates, e.g. cadmium, zinc, tin or lead fluoborates.  Specified amino hydroxy compounds are mono-, di- and tri-ethanolamines, diethylaminoethanol, mono- and triisopropanolamines, hydroxyethyl ethylene diamine and N-phenyl diethanolamine; mixtures of the amino hydroxy compounds may be used. The reagents may be used in equimolecular proportions as in making boron trifluoridetriethanolamine or excess of either reactant may be used; a preferred addition compound is obtained by the combination of hydrofluoboric acid and a heavy metal fluoborate with the aminohydroxy compound.  The addition compounds are preferably made by adding the borofluoridic compound to excess of the amino hydroxy compound whereby a solution of the addition compound is obtained. The addition compounds are used as or in solder fluxes (see Group II). A specified flux is a 10 per cent solution in triethanolamine of the addition compound of hydrofluoboric acid and triethanol amine and another is composed of 12 grams hydrofluoboric acid, 8 grams cadmium fluoborate and 100 grams triethanolamine.  Specification 684,082, [Group II], is referred to.  The samples furnished under Sect. 2 (5) are addition compounds prepared by bubbling BF3 through liquid carbamyl-bis-aminoethylethanolamine, 1-hydroxyethyl diethylene triamine, 1 - hydroxyethyl - 2 - heptadecenyl glyoxalidine and alpha-methyl benzyl monoethanolamine respectively until no further increase in weight is observed.  Carbamyl-bis-aminoethyl ethanolamine is prepared by reacting urea with two mols. of aminoethyl ethanolamine at about 150 DEG  C.ALSO:A solder flux comprises an addition compound formed by reacting an organic compound containing amino and alcoholic hydroxyl groups and at least two carbon atoms with a boro-fluoridic compound such as BF3, hydrofluoboric acid and heavy metal fluoborates, e.g. cadmium, zinc, tin or lead fluoborates. Specified amino hydroxy compounds are mono-, di- and triethanolamines, diethylaminoethanol, mono- and triisopropanolamines, hydroxyethyl ethylene diamine and N-phenyl diethanolamine; mixtures of the amino hydroxy compounds may be used. The addition compound may consist of the two reagents combined in equimolecular proportions as in triethanolamine p  - boron trifluoride or excess of either reactant may be present; a preferred addition compound is obtained by the combination of hydrofluoboric acid and a heavy metal fluoborate with the amino hydroxy compound. The addition compound may be used as a flux alone or in conjunction with a flux vehicle or carrier such as water, alcohol or excess of the amino hydroxy compound, and with other flux ingredients such as zinc, cadmium, tin, lead and other heavy metal fluorides, and plasticisers such as mineral jelly, stearic acid, oleic acid and paraffin; there may also be present boro-fluoridic addition compounds of non-hydroxylic polyamines. The fluxes are preferably made by adding the borofluoridic compound to excess of the amino hydroxy compound whereby a solution of the flux results.  The fluxes may be used in the soldering of aluminium and its alloys, iron, copper, nickel, brass, certain steels and magnetic iron base alloys containing aluminium; soft solders and "hot plate" soldering methods may be used.  A specified flux is a 10 per cent solution in triethanolamine of the addition compound of hydrofluoboric acid and triethanolamine and another is composed of 12 grams hydrofluoboric acid, 8 grams cadmium fluoborate and 100 grams triethanolamine. Specification 684,082 is referred to.  The samples furnished under Sect. 2 (5) are addition compounds formed by bubbling BF3 through liquid carbamylbisaminoethyl-ethanolamine, 1-hydroxyethyl diethylene triamine, 1-hydroxyethyl-2-heptadecenyl glyoxalidine and alpha-methyl-benzyl monoethanolamine respectively until no further increase in weight is observed.