# US 10,441,971 B2 · Process for coating a substrate body > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,441,971 B2 - Document ID: US10441971B2 - Status: Granted - Kind: B2 - Application number: 15/503,588 - Filed: 2015-08-05 - Published: 2017-08-17 - Granted: 2019-10-15 - Earliest claimed: 2014-08-14 - Assignees: Umicore AG & Co. KG - Applicants: Umicore AG & Co. KG - Inventors: Stéphane Masson - Web page: https://patentgrep.com/patent/US10441971B2 ## CPC - B05D 7/22: to internal surfaces, e.g. of tubes - B01J 35/19: {Catalysts containing parts with different compositions} - B01J 35/56: Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional [3D] monoliths - B01J 37/0215: {Coating} - B01J 37/0246: {Coatings comprising a zeolite} - B01J 37/0248: {Coatings comprising impregnated particles} - B05C 3/02: the work being immersed in the liquid or other fluent material - B05C 7/04: the liquid or other fluent material flowing or being moved through the work; the work being filled with liquid or other fluent material and emptied - B05D 1/18: performed by dipping - C04B 38/0006: {Honeycomb structures (from one or more corrugated sheets by winding or stacking C04B38/0083)} - C04B 38/0012: {characterised by the material used for sealing or plugging (some of) the channels of the honeycombs} - F01N 3/0222: {the structure being monolithic, e.g. honeycombs} - F01N 3/28: Construction of catalytic reactors - B05D 2254/04: Applying the material on the interior of the tube - B05D 2259/00: Applying the material to the internal surface of hollow articles other than tubes - F01N 2230/06: Spark arresters - F01N 2510/06: for exhaust purification, e.g. catalytic reaction - B05D: PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL (conveying articles or workpieces through baths of liquid B65G, e.g. B65G49/02) - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS - B05C: APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL (spraying apparatus, atomising apparatus, nozzles B05B; plant for applying liquids or other fluent materials to objects by electrostatic spraying B05B5/08) - C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE - F01N: GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES (arrangements in connection with gas exhaust of propulsion units in vehicles B60K13/00; combustion-air intake silencers specially adapted for, or arranged on, internal-combustion engines F02M35/00; protecting against, or damping, noise in general G10K11/16) ## Abstract A method of catalytically coating a honeycomb monolith, in particular a so-called flow-through monolith, is featured. The process involves quite precisely coating the monolith with a method that uses an indirect coating via a displacement body. The method included controlling the process by monitoring certain measures and controlling the liquid coating medium feed as to limit bubble formation in the liquid coating medium. ## Claims ### Claim 1 A process for applying a washcoat, with a liquid coating medium, to an exhaust gas purification substrate, the substrate having a support body with two end faces and an axial length traversed from the first end face to the second end face by a multiplicity of channels, the process comprising supplying the liquid coating medium to the substrate with a liquid supply apparatus that comprises a cylinder containing a displacement liquid and a piston, wherein the displacement liquid in the cylinder communicates with a tank, an interior of the tank having a displacement body arranged in such a way that, when the piston is moved, the displacement body is moved proportionally by the displacement liquid, and the tank communicates with a coating device for the substrate, wherein the displacement body acts on the liquid coating medium, with the result that movement of the displacement body brings about a proportional change in the level of liquid coating medium in the coating device, wherein movement of the piston, which leads to an adjustment in the displacement body, is controlled by a control unit that is configured to limit piston velocity as to avoid generation of bubbles in the washcoat. ### Claim 2 (depends on 1) The process according to claim 1, wherein the control unit is configured to limit the velocity of the piston during a movement that leads to a deflation adjustment in the displacement body, and to limit the velocity of the piston during that movement to between 0.01-3 m/s. ### Claim 3 (depends on 2) The process according to claim 2, wherein the viscosity of the liquid coating medium is between 2-200 mPa*s. ### Claim 4 (depends on 2) The process according to claim 2, wherein the control unit controls piston movement during a backstroke movement such that the piston is accelerated at initiation of the backstroke movement and decelerated at an end region of the backstroke movement. ### Claim 5 (depends on 1) The process according to claim 1, wherein the control unit is configured to limit the velocity of the piston during a backstroke movement that leads to a deflation adjustment in the displacement body, and to control the backstroke movement such that the piston is first accelerated and then decelerated to an end of the backstroke movement. ### Claim 6 (depends on 1) The process according to claim 1, wherein the process includes monitoring a sensor that is used to control the velocity of the piston, wherein the sensor is selected from the group consisting of: a pressure sensor, an optical sensor, a conductivity sensor, and a vibration sensor. ### Claim 7 (depends on 1) The process according to claim 1, wherein the velocity of the piston is controlled during a backstroke movement of the piston. ### Claim 8 (depends on 1) The process according to claim 1, wherein the control unit controls piston movement to have a Gaussian distribution velocity curve profile during a backstroke movement. ### Claim 9 (depends on 1) The process according to claim 1, wherein the control unit is configured to limit piston velocity during a movement of the piston leads to a deflation adjustment in the displacement body. ### Claim 10 (depends on 9) The process according to claim 9, wherein the piston generates deflation adjustment in the displacement body during a backstroke. ### Claim 11 (depends on 1) The process according to claim 1, wherein the liquid supply apparatus further comprises a pressure sensor adapted to detect pressure discontinuities in the tank, and the control unit is configured to limit the velocity of the piston based on detection of pressure discontinuities by the pressure sensor. ### Claim 12 (depends on 1) The process according to claim 1, wherein the control unit is configured to execute in-process-control of the movement of the piston, such that the limitation on piston velocity is adjusted over a production campaign based on changes to the viscosity of the liquid coating medium over the production campaign. ### Claim 13 A coating process for applying a liquid coating medium with a liquid coating apparatus, to form a washcoat on an exhaust gas purification substrate, the substrate having a support body with two end faces and an axial length that is traversed from the first end face to the second end face by a multiplicity of channels, wherein the coating apparatus comprises: a cylinder comprising a piston and a displacement liquid; a tank storing the liquid coating medium, an interior of the tank having a displacement body that is movable by the displacement liquid in the cylinder; a coating device adapted for receiving an exhaust gas purification substrate, the coating device being in communication with the tank for directing liquid coating medium from the tank to channels of the exhaust gas purification substrate, wherein the coating apparatus is adapted such that movement of the piston causes a movement of the displacement liquid, with movement of the displacement liquid causing an adjustment in the displacement body, with adjustment of the displacement body causing a proportional change in a level of liquid coating medium in the coating device, the coating process comprising: controlling a backstroke movement of the piston by a control unit configured to limit a velocity of the piston during the backstroke movement as to avoid generation of bubbles in the liquid coating medium stored in the tank. ### Claim 14 (depends on 13) The coating process according to claim 13, wherein the velocity of the piston during the backstroke movement is controlled to be between 0.01-3 m/s, the backstroke movement causing a deflation adjustment in the displacement body. ### Claim 15 (depends on 14) The coating process according to claim 14, wherein the viscosity of the liquid coating medium is between 2-200 mPa*s. ### Claim 16 (depends on 13) The coating process according to claim 13, wherein the velocity of the piston during the backstroke movement is controlled such that the piston is accelerated at a beginning of the backstroke movement and decelerated at an end of the backstroke movement, with the backstroke movement causing a deflation adjustment in the displacement body. ### Claim 17 (depends on 13) The coating process according to claim 13, further comprising monitoring a sensor for controlling the velocity of the piston during the backstroke movement, the sensor being selected from the group consisting of: a pressure sensor, an optical sensor, a conductivity sensor, and a vibration sensor. ### Claim 18 (depends on 14) The coating process according to claim 14, wherein the control unit controls piston movement during backstroke movement such that the piston is accelerated at initiation of the backstroke movement and decelerated at an end region of the backstroke movement. ### Claim 19 (depends on 13) The coating process according to claim 13, wherein the control unit controls piston movement to have a Gaussian distribution velocity curve profile during the backstroke movement. ### Claim 20 (depends on 13) The coating process according to claim 13, wherein the backstroke movement of the piston leads to a deflation adjustment in the displacement body. ### Claim 21 (depends on 13) The coating process according to claim 13, wherein the coating apparatus further comprises a pressure sensor adapted to detect pressure discontinuities in the tank, and the coating process further comprises limiting the velocity of the piston during the backstroke movement based on detection of pressure discontinuities by the pressure sensor. ### Claim 22 (depends on 13) The coating process according to claim 13, wherein the control unit is configured to execute in-process-control of the movement of the piston, such that the limitation on piston velocity is adjusted over a production campaign based on changes to the viscosity of the liquid coating medium over the production campaign.