Cleaning process including use of solvating and rinsing agents
US5679175A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 14, 1993 |
| Grant date | Oct 21, 1997 |
| Priority date | — |
| Expiry date | Dec 14, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/0783
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A process for removing soil from a substrate which includes the use of liquid cleaning composition including a solvating agent (for example, a monobasic ester) and a rinsing agent (for example, a perfluorocarbon), the solvating agent having: PA1 (i) a room temperature vapor pressure of no greater than about 40 mm Hg; and PA1 (ii) a solvating strength of no less than about 10; PA1 and the rinsing agent having: PA1 (iii) a room temperature vapor pressure of about 8 mm Hg to about 760 mm Hg; and PA1 (iv) an ozone depleting factor of no greater than about 0.15; wherein the ratio of the vapor pressure of the rinsing agent to the vapor pressure of the solvating agent is at least about 20 and such that, at the boiling temperature of the composition, the vapor space above the boiling composition would include the rinsing agent and be substantially free of the solvating agent, the process including immersing an article (for example, a printed circuit board having thereon solder flux) in the boiling composition, withdrawing the article from the composition and transferring it through the vapor space and into a container of relatively cool liquid rinsing agent from which it is withdrawn and t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.