Flux-removing aqueous cleaning composition and method of use
US5772789A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 19, 1996 |
| Grant date | Jun 30, 1998 |
| Priority date | — |
| Expiry date | Nov 19, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/0793
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
An aqueous cleaning composition which is capable of removing soldering flux residues, particularly water-soluble flux residues, from a surface of an electronic assembly without leaving significant amounts of white residue on the surfaces of cleaning equipment used in the flux-removal process, contains: (A) a flux-removing portion containing an alkaline salt component composed of at least one potassium salt; and (B) an aqueous portion in which the flux-removing portion is disposed. The composition has a non-potassium alkali metal content of no greater than about 5% by weight. Preferably, the alkaline salt component consists essentially of a potassium salt or mixture of potassium salts, most preferably potassium carbonate or a mixture of potassium carbonate salts. A method of substantially removing soldering flux residues from an electronic assembly surface without leaving significant amounts of white residue on surfaces of cleaning equipment used in the flux-removal method involves applying the aforementioned cleaning composition onto the electronic assembly surface for a period of time sufficient to substantially saponify the flux residues so as to form saponified flux residues, an…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.