Ternary azeotropic compositions
Abstract
Abstract CERTAIN TERNARY MIXUTRES OF TETRACHLORODIFLUOROETHANE (SYM-, ASYM-, AND MIXTURES THEREOF) ISOPROPANOL AND NITROMETHANE ARE USEFUL AS SOLVENTS TO REMOVE ROSIN FLUXES FROM PRINTED CIRCUIT BOARDS CONTAINING THE SAME. THESE MIXTURES ARE USEFUL NOT ONLY BECAUSE OF THEIR HIGH SOLVENCY CHARACTERISTICS BUT ALSO BECAUSE THEY EXHIBIT ESSENTIALLY THE CONSTANT BOILING CHARACTERISTICS OF A TERNARY AZEOTROPE WHICH IS FORMED BETWEEN THESE COMPONENTS, THEREBY FACILITATING HANDLING AND PURIFICATION OF THE SOLVENT MIXUTRES WITHOUT SIGNIFICANTLY ALTERING THEIR COMPOSITIONS. THE TERNARY MIXTURES DISCLOSED HEREIN EXHIBIT SUBSTANTIALLY HIGHER SOLVENCY CHARACTERISTIS FOR ROSIN FLUXES THAN THE PURE SOLVENTS, TETRACHLORODIFLUOROETHANE, ISOPROPANOL OR NITROMETHANE.
Inventors
- 👤 Oliver A Barton
- 👤 Kevin P Murphy
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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