Browse Prior Art Database

Powder-Coating Method for Carrier

IP.com Disclosure Number: IPCOM000041603D
Original Publication Date: 1984-Feb-01
Included in the Prior Art Database: 2005-Feb-02
Document File: 1 page(s) / 12K

Publishing Venue

IBM

Related People

Meyer, TR: AUTHOR

Abstract

Electrophotographic carrier is currently coated by suspending the steel shot substrate in a fluidizing air stream. The coating material is applied as a liquid suspension sprayed into the moving bed of shot. Polymerizing and sintering of the coating material is then performed in conveyorized ovens. During this "curing" process the carrier beads fuse into "bricks" that must be fragmented back into individual carrier beads. The proposed coating method eliminates many of the problems of the above-mentioned process. Additionally, less time, energy and direct labor are required. In the proposed process the coating material is in the form of a dry, finely divided powder. This powder is fluidized by a low velocity air stream introduced through an air distributor plate at the bottom of the fluidizing chamber.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 55% of the total text.

Page 1 of 1

Powder-Coating Method for Carrier

Electrophotographic carrier is currently coated by suspending the steel shot substrate in a fluidizing air stream. The coating material is applied as a liquid suspension sprayed into the moving bed of shot. Polymerizing and sintering of the coating material is then performed in conveyorized ovens. During this "curing" process the carrier beads fuse into "bricks" that must be fragmented back into individual carrier beads. The proposed coating method eliminates many of the problems of the above-mentioned process. Additionally, less time, energy and direct labor are required. In the proposed process the coating material is in the form of a dry, finely divided powder. This powder is fluidized by a low velocity air stream introduced through an air distributor plate at the bottom of the fluidizing chamber. The steel shot substrate, possibly preheated, would be sprinkled into the fluidized coating powder from above. The temperature of the shot would be maintained at a level above the melting point of the coating powder by radio frequency energy supplied by coils around the outside of the fluidizing chamber (inductive heating). As the heated shot passes through the bed of fluidized powder, powder coming into contact with the shot fuses to the shot surface. An unheated zone at the bottom of the fluidized bed would allow time for the shot to cool before landing upon the air distributor plate. The coated shot would be continuously removed f...