Cleaning with solvating and rinsing agents
US5716457A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 6, 1995 |
| Grant date | Feb 10, 1998 |
| Priority date | — |
| Expiry date | Jun 6, 2015 |
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 a liquid cleaning composition comprising 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; 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 said rinsing agent to the vapor pressure of said 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 comprise said rinsing agent and be substantially free of said solvating agent, the preferred 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 w…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.