Subliming solder flux composition
US5296046A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 16, 1993 |
| Grant date | Mar 22, 1994 |
| Priority date | — |
| Expiry date | Aug 16, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K3/3489
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A fluxing composition for soldering metals together, contains a carrier solvent, an oxide removing agent, and a nitrogen liberating compound. The oxide removing agent sublimes at or below the temperature at which the metals are soldered together. The nitrogen liberating compound sublimes or decomposes at below the temperature at which the metals are soldered together in order to provide a blanket of inert gas over the metals being soldered. The oxide removing agent is 2-amino-isophthalic acid, 5-amino-isophthalic acid, isophthalic acid, ammonium fluoborate, or ammonium salicylate. The compound that liberates nitrogen upon heating is 1,2-benz-3,4-anthraquinone, 1,2-benz-9,10-anthraquinone, 5,6-chrysoquinone, 6,12-chrysoquinone, 2,3-benzanthraquinone, 2-amino-isophthalic acid, 5-amino-isophthalic acid, or 5-isoquinoline carboxylonitrile. Electronic components are soldered to a circuit board by applying the fluxing composition to the circuit board. The fluxing composition, the component and the circuit board are heated to a temperature sufficient to cause the activator to react with metal oxides on either the component or the circuit board and to sublime, and also to a temperature to …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.