William R Hendrickson

US Patent:

58173749, Oct 6, 1998

Filed:

May 31, 1996

Appl. No.:

8/656089

Inventors:

Robert H. Detig - Berkeley Heights NJ
William A. Hendrickson - Houlton WI

Assignee:

Electrox Corporation - Newark NJ

International Classification:

B05D 106
B05D 132

US Classification:

427466

Abstract:

Particles are applied to the surfaces of materials, especially in the form of discontinuous or patterned coatings on the surfaces of sheet materials by a process comprising the steps of: a) providing a support, b) placing a bed of non-adhered particles on the support, the particles being capable of being moved by an electric field of less than 100 KV/cm, c) placing a mask with a first and second surface over the bed of non-adhered particles, the mask having holes which pass from the first to the second surface, the first surface facing the bed of non-adhered particles without the mask touching the bed of non-adhered particles, the holes in the mask having a size which would allow passage of individual particles from the bed of non-adhered particles through the holes, d) placing a receptor material capable of at least temporarily retaining an electric charge adjacent to the second surface of the mask, which second surface faces away from the bed of non-adhered particles, e) applying an electrical charge to the receptor material which is at least temporarily retained by the receptor material, f) applying an electrical field between the mask and the support, the electrical field being of at least sufficient strength to cause individual particles from the bed of non-adhered particles to move off the first substrate and impact the mask, g) allowing some of the individual particles which move off of the support to enter the holes in the mask and contact the receptor material, and h) the contract by individual particles to the receptor material causing at least some of the particles contacting the receptor material to adhere to the receptor material at least by charge attraction of the individual particles to charge on the receptor material.