Spray application of coating compositions utilizing induction and corona charging means
US4266721A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 17, 1979 |
| Grant date | May 12, 1981 |
| Priority date | — |
| Expiry date | Sep 17, 1999 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB05B5/043
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Disclosed is a spray gun having a gas nozzle and a fluid nozzle, each of the nozzles being in cooperative spatial relationship with the other to cause a fluid stream issuing from the fluid nozzle to be atomized and sprayed as fluid particles by gas issuing from the gas nozzle. In a preferred embodiment the fluid nozzle orifice has therein an axially disposed rod to increase surface area from which the fluid particles can be found, the rod being a corona discharge electrode of a first polarity. The spray gun additionally has an induction charging electrode of a second polarity opposite the first polarity and disposed adjacent the gas and fluid nozzles, the induction charging electrode defining a charging zone wherein an electrostatic charge is imparted to atomized electrically-chargeable fluid particles. Relatedly disclosed is a method of applying a liquid coating composition having an electrical conductivity of less than about 0.06 .mu.mho/cm to a workpiece through utilization of both corona and induction charging in a spray gun.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.