Method of applying surface hydrophilic treatment to heat-transfer tube
US5445682A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 7, 1994 |
| Grant date | Aug 29, 1995 |
| Priority date | — |
| Expiry date | Jul 7, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49391
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method of applying a surface hydrophilic treatment to a heat-transfer tube with a good productivity, which obtains an excellent surface hydrophilic property not deteriorated for a long term. The method includes the steps of: heating a copper or copper alloy heat-transfer tube for 5 to 10 min at a temperature ranging from 250.degree. to 350.degree. C. in an atmosphere mainly containing an inert gas; and applying corona discharge or plasma discharge to the copper or copper alloy heat-transfer tube. To prevent the coloring, the atmosphere preferably contains O.sub.2 in a concentration of 3% or less and CO in a concentration of 1 to 5%, the balance being an inert gas.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.