Method of making push button switch covering with protective coating
US6270860A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 25, 1995 |
| Grant date | Aug 7, 2001 |
| Priority date | — |
| Expiry date | Apr 25, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31598
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A push button switch covering member of a silicone rubber is imparted with excellent resistance against stain deposition and abrasive wearing by providing a protective overcoating layer of a urethane resin-based coating composition capable of being cured by forming urethane linkages between isocyanate groups of a polyisocyanate compound and hydroxy groups of a polyhydroxy compound. The coating procedure with the coating composition on the surface of a silicone rubber-made covering member is preceded by a plasma treatment so as to activate the surface resulting in an increased adhesive bonding strength between the silicone rubber body and the coating layer. The improvement is more remarkable when the plasma-activated surface is subjected to a priming treatment with a silane coupling agent and coating with the coating composition is undertaken as soon as possible or within 60 minutes after completion of the plasma treatment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.