Browse Prior Art Database

Electrophoretic Coating of Wires

IP.com Disclosure Number: IPCOM000090954D
Original Publication Date: 1969-Aug-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 3 page(s) / 52K

Publishing Venue

IBM

Related People

Damm, EP: AUTHOR [+2]

Abstract

A metal wire is continuously encapsulated in an insulative sheath by this apparatus, drawing A. Multiple wires are similarly encased in a sheath by the variant shown in drawing B. The latter multiwire arrangement is useful for example as a transmission medium for high-frequency electrical signals.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 53% of the total text.

Page 1 of 3

Electrophoretic Coating of Wires

A metal wire is continuously encapsulated in an insulative sheath by this apparatus, drawing A. Multiple wires are similarly encased in a sheath by the variant shown in drawing B. The latter multiwire arrangement is useful for example as a transmission medium for high-frequency electrical signals.

Guide sleeve 1, drawing A, receives wire 2 and guides it through a section D of fluid in bath 3. The latter is a part of electrophoretic coating apparatus 4. The insulative sheath is formed by electrophoretic deposition from bath 3. Sleeve 1 is made of polytetrafluoroethylene or like material. This material has a low coefficient of friction, which operates to ease passage of wire 2, and has a low critical surface tension, 16-19 dynes per cm, which acts to prevent bath fluid from contacting wire 2 within sleeve 1. By excluding the bath fluid from sleeve 1, the thickness of coating 6 which forms the insulative sheath, assuming a constant rate of delivery of wire 2, becomes an exclusive function of the distance D traversed by the wire in passing from exit end 7 of sleeve 1 to the surface of bath 3 at 8, i.e., an exclusive function of bath level.

Voltage V applied through switch S and wipe member W across the outer electrode represented by conductive inner lining 5 of tank 4 and the inner electrode represented by wire 2 causes a polymer coating to deposit upon the length D of wire which is in contact with bath 3. The thickness of the coating is determined by the duration of exposure of any section of wire 2. To ensure uniform and symmetric coating, wire 2 is reeled through bath 3 at constant speed and in constant alignment with the axis of electrode 5 while it receives the coating. For this purpose the exit end 7 of sleeve 1 is mounted in a positioning frame 9, drawing B...