# US 8,540,351 B1 · Deflection plate for liquid jet printer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,540,351 B1 - Document ID: US8540351B1 - Status: Granted - Kind: B1 - Application number: 13/411,684 - Filed: 2012-03-05 - Published: 2013-09-05 - Granted: 2013-09-24 - Earliest claimed: 2012-03-05 - Assignees: Milliken & Company - Applicants: Franklin S. Love, III; Jeffrey J. Lillie; Daniel T. McBride; Rajib Mondal; Robert M. MacMeccan - Inventors: Franklin S. Love, III; Jeffrey J. Lillie; Daniel T. McBride; Rajib Mondal; Robert M. MacMeccan - Web page: https://patentgrep.com/patent/US8540351B1 ## CPC - B41J 2/07: characterised by jet control (B41J2/205 takes precedence) - B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS ## Abstract A liquid jet printing apparatus is provided having a nozzle for emitting a stream of liquid droplets toward a substrate, a charging section for providing an electrical charge to liquid droplets and a pair of electrically conductive deflecting plates for deflecting the liquid droplets to a desired location on the substrate, wherein the inside face of the deflecting plates is provided with dielectric layer to minimize problems associated with liquid droplets collecting and coalescing on the deflecting plates. ## Claims ### Claim 1 An apparatus for printing on a substrate, comprising: (a) a nozzle capable of emitting a stream of individual droplets of liquid toward the substrate; (b) a droplet charging section capable of providing an electrical charge to the droplets; (c) a pair of electrically conductive deflecting plates for creating an electrical field capable of deflecting the droplets to a desired location of the substrate, wherein each of the plates has an interior side facing the path of the stream of individual droplets of liquid, and wherein an outer layer of the interior side of at least one of the deflecting plates is a dielectric. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the dielectric outer layer is selected from the group consisting of dielectric coatings and metal oxides grown on the surface of the deflecting plate. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the interior sides of both deflecting plates have a dielectric outer layer. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the dielectric outer layer is a polymer. ### Claim 5 (depends on 4) The apparatus of claim 4, wherein the dielectric polymer is selected from the group consisting of poly(p-xylylene) polymers, silicone polymers, polyurethanes, epoxy polymers, polyolefins, and polyacrylates. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the dielectric outer layer is selected from the group consisting of poly(p-xylylene), poly(3-chloro-p-xylylene) and poly(3,6-dichloro-p-xylylene). ### Claim 7 (depends on 6) The apparatus of claim 6, wherein the dielectric outer layer is applied by vapor deposition. ### Claim 8 (depends on 1) The apparatus of claim 1, wherein the dielectric outer layer has a dielectric strength of greater than 500 V/mil. ### Claim 9 (depends on 1) The apparatus of claim 1, wherein the dielectric outer layer has a thickness of 100 nm to 0.1 mm. ### Claim 10 (depends on 1) The apparatus of claim 1, further comprising a hydrophobic film overlaying the dielectric outer layer, wherein the contact angle between water and the hydrophobic film is 85° or greater. ### Claim 11 (depends on 1) The apparatus of claim 1, further comprising a hydrophobic film overlaying the dielectric outer layer, wherein the hydrophobic film is selected from the group consisting of functionalized and unfunctionalized polyolefins, polytetrafluoroethylenes, glass, quartz, epoxies, polyacrylates, and polyurethanes. ### Claim 12 (depends on 1) The apparatus of claim 1, further comprising a hydrophobic film overlaying the dielectric outer layer, wherein the hydrophobic film comprises fluoroalkyl acrylate copolymer and fumed silica. ### Claim 13 (depends on 12) The apparatus of claim 12, wherein the hydrophobic film further comprises a crosslinkable polymer and a crosslinking agent. ### Claim 14 (depends on 1) The apparatus of claim 1, wherein the dielectric outer layer is selected from the group consisting of oxides of Al, Ti, Ta, Nb, Zr, Hf, W, Si and perovskites. ### Claim 15 (depends on 14) The apparatus of claim 14, wherein the deflecting plates are aluminum and the dielectric outer layer is Al2O3 formed by etching the deflecting plate and growing the Al2O3 on the etched surface. ### Claim 16 (depends on 14) The apparatus of claim 14, further comprising a hydrophobic film overlaying the dielectric outer layer, wherein the contact angle between water and the hydrophobic film is 85° or greater. ### Claim 17 (depends on 1) The apparatus of claim 1, wherein the dielectric outer layer is hydrophobic with a contact angle between water and the dielectric layer of 85° or greater. ### Claim 18 (depends on 1) The apparatus of claim 1, wherein the liquid is aqueous and comprises a colorant selected from the group consisting of acid dyes, disperse dyes and reactive dyes. ### Claim 19 A method of printing on a substrate, comprising the steps of: (a) emitting a stream of individual droplets of liquid toward the substrate with a nozzle; (b) providing an electrical charge to the droplets; (c) deflecting the droplets to a desired location of the substrate, using a pair of electrically conductive deflecting plates capable of creating an electrical field, wherein each of the plates has an interior side facing the path of the stream of individual droplets of liquid, and wherein an outer layer of the interior side of at least one of the deflecting plates is a dielectric. ### Claim 20 (depends on 19) The method of claim 19, wherein the interior sides of both deflecting plates have a dielectric outer layer. ### Claim 21 (depends on 20) The method of claim 20, wherein the dielectric outer layer is selected from the group consisting of dielectric polymer coatings and metal oxides. ### Claim 22 (depends on 21) The method of claim 21, further comprising a hydrophobic film overlaying the dielectric outer layer, wherein the contact angle between water and the hydrophobic film is 85° or greater.