Method of dip coating fuser belt using alcohol as a co-solvent

• US 6,511,709 B1
• Filed: 08/15/2001
• Issued: 01/28/2003
• Est. Priority Date: 08/15/2001
• Status: Expired due to Term

• Current Assignee: Lexmark International Incorporated (Ninestar Corporation)
• Original Assignee: Lexmark International Incorporated (Ninestar Corporation)
• Inventors: Nguyen, Dat Quoc, Weisman, Mark Stephen Jr., Srinivasan, Kasturi Rangan, Broce, Scott Moreland, Minor, James Craig, Barnes, Johnathan Lee, Neely, Jennifer Kaye
• Primary Examiner(s): BARR, MICHAEL E
• Application Number:
  US09/930,628
• Time in Patent Office: 531 Days
• Field of Search: 427/430.1, 427/385.5, 427/412.1, 427/407.1
• US Class Current: 427/430.1
• CPC Class Codes: B05D 1/18 performed by dipping
• CPC Class Codes: B05D 5/083 involving the use of fluoropolymers
• CPC Class Codes: G03G 15/2057 relating to the chemical composition of the heat element and layers thereof
• CPC Class Codes: G03G 2215/2016 Heating belt

Abstract

A process for dip coating, particularly vertical dip coating, the topcoat layer onto fuser belts used in electrophotographic processes is disclosed. In this process, a C₁-C₄ alkanol, such as isopropyl alcohol is added to the solvent system for the fluorocarbon topcoat layer. The use of alcohols in this way provides an efficient and effective method and a topcoat layer which is smooth, uniform and has a good finish.

Claims

1. In a method for coating a polyimide film with a fluorocarbon, said film being a continuous belt for a belt fuser, the improvement which comprises dipping said film into an aqueous-based solution which comprises from about 30% to about 50% by weight of said fluorocarbon, and about 7% by weight of a C₁-C₄ alkanol, and drying said fluorocarbon layer.

2. The coating method according to claim 1 wherein the alkanol is selected from methanol, ethanol, butanol, propanol, and mixtures thereof.

3. The coating method according to claim 2 wherein the alkanol is isopropyl alcohol.

4. The coating method according to claim 3 wherein the polyimide film has coated on its outer surface a conductive primer layer.

5. The coating method according to claim 4 wherein the fluorocarbon is a perfluoroalkoxy resin.

6. The coating method according to claim 5 wherein the coating takes place by a vertical dip coating technique.

7. The coating method according to claim 6 wherein the coating solution contains from about 30 to about 34% by weight total solids.

8. The coating method according to claim 6 wherein the fluorocarbon is selected from the group consisting of polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkylvinylether copolymers, and tetrafluoroethylene hexafluoropropylene copolymers.

9. The coating method according to claim 6 wherein the fluorocarbon layer has a thickness of from about 9 to about 15 μ

m.

10. The coating method according to claim 6 wherein the fluorocarbon layer has a roughness (R_Z) of no greater than about 6 μ

m.

11. The coating method according to claim 6 wherein the fluorocarbon material is selected from the group consisting of polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkylvinylether copolymers, and tetrafluoroethylene hexafluoropropylene copolymers and the coating solution contains from about 30% to about 34% by weight total solids.

12. The coating method according to claim 11 wherein the fluorocarbon layer has a thickness of from about 9 to about 15 μ

m and a roughness (R_Z) of no greater than about 6 μ

m.

13. The coating method according to claim 6 wherein the fluorocarbon layer is dried by heating.