# US 4,395,441 A · Method of coating liquid penetrable articles with polymeric dispersions > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,395,441 A - Document ID: US4395441A - Status: Granted - Kind: A - Application number: 06/285,860 - Filed: 1981-07-22 - Granted: 1983-07-26 - Earliest claimed: 1978-08-15 - Inventors: Robert G. Farnam - Web page: https://patentgrep.com/patent/US4395441A ## CPC - F16J 15/108: {Special methods for making a non-metallic packing} - B05D 3/0218: {Pretreatment, e.g. heating the substrate} - B05D 3/0227: {with IR heaters} - B05D 3/0254: {After-treatment} - B05D 3/0263: {with IR heaters} - B05D 2401/20: Aqueous dispersion or solution - F16J: PISTONS {(specially adapted for dampers F16F9/32)}; CYLINDERS; SEALINGS - B05D: PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL (conveying articles or workpieces through baths of liquid B65G, e.g. B65G49/02) ## Abstract A liquid penetrable material such as a compactible gasket material is coated with a liquid dispersion of polymer or polymers, by first preheating the liquid penetrable material to a temperature sufficient to prevent any substantial penetration of liquid into the material when the material at the preheated temperature is coated with the liquid dispersion of polymer or polymers. The preheated material is then coated with the liquid dispersion of polymer or polymers in an amount sufficient to form a fluid-impermeable barrier over the material and the coated material is supported on a plurality of support members through a drying section until the coating is in a tack-free condition. After drying the material to a tack-free condition, it is supported on a conveyor through a curing station to cure the coating. Thereafter the material is delivered by suitable conveyors to an inspection and packaging station, but may be passed en route through another coating station, this time to receive a suitable release coating. In a specific embodiment of the invention, the gasket is supported through the drying section on a plurality of continuous elastomeric cords. ## Claims ### Claim 1 A method of coating a liquid-penetrable material with a liquid dispersion of a polymer, comprising: preheating said liquid-penetrable material to a temperature sufficient to prevent any substantial penetration of liquid into said material when said material, at said preheated temperature, is contacted with a liquid dispersion of a polymer; coating a major surface of said preheated material while at said temperature with a liquid dispersion of a curable polymer; supporting the coated, liquid-penetrable material on a plurality of elastomeric elongated support members while said coating is dried to a substantially tack-free condition; and curing said coating to form a polymer-coated article. ### Claim 2 (depends on 1) A method as defined in claim 1 wherein said liquid-penetrable material is gasket material. ### Claim 3 (depends on 1) A method as defined in claim 1 wherein said liquid dispersion of a polymer is a water dispersion of a polymer and wherein said water penetrable material is preheated to and maintained at a temperature of at least 125.degree. F. prior to coating. ### Claim 4 (depends on 1) A method as defined in claim 1 wherein said liquid-penetrable material is preheated to and maintained at a temperature between about 125.degree. F. and 250.degree. F. prior to coating. ### Claim 5 (depends on 1) A method as defined in claim 1 wherein said liquid-penetrable material is preheated to and maintained at a temperature of at least 150.degree. F. prior to coating. ### Claim 6 (depends on 1) A method as defined in claim 1 wherein said elastomeric support members comprise a plurality of spaced polyurethane cords. ### Claim 7 A method of coating a liquid-penetrable material with a liquid dispersion of a polymer, comprising: preheating said liquid-penetrable material to a temperature sufficient to prevent any substantial penetration of liquid into said material when said material, at said preheated temperature, is contacted with a liquid dispersion of a polymer; maintaining said preheated material at a temperature sufficient to prevent any substantial penetration of liquid into said material when said material is contacted with a liquid dispersion of a polymer, until immediately prior to coating said material with a liquid dispersion of a polymer; coating said preheated material with a liquid dispersion of a curable polymer in an amount sufficient to form a fluid impermeable barrier over said material after curing said coating; supporting said coated material on a plurality of gasket suspension members through a drying station said suspension members having a material contact area sufficiently small that any depressions made in the polymer coating are healed over during curing; drying said coated material at said drying station in an amount sufficient to provide a tack-free polymer coating on said material; and curing said polymer coating. ### Claim 8 (depends on 7) A method as defined in claim 7 wherein said gasket suspension members in said drying station comprise elastomeric cords. ### Claim 9 (depends on 8) A method as defined in claim 8 wherein said elastomeric cords are polyurethane cords. ### Claim 10 (depends on 7) A method as defined in claim 7 wherein said liquid-penetrable material is gasket material. ### Claim 11 (depends on 7) A method as defined in claim 7 wherein said liquid dispersion of a polymer is a water dispersion of a polymer and wherein said water penetrable material is preheated to and maintained at a temperature of at least 135.degree. F. prior to coating. ### Claim 12 A method of coating a liquid-penetrable material with a liquid dispersion of a polymer, comprising: preheating said liquid-penetrable material to a temperature sufficient to prevent any substantial penetration of liquid into said material when said material, at said preheated temperature, is contacted with a liquid dispersion of a polymer; coating a major surface said preheated material while at said temperature with a liquid dispersion of a curable polymer; supporting the coated, liquid-penetrable material on a plurality of support members while said coating is dried to a substantially tack-free condition; and curing said coating to form a polymer-coated article. ### Claim 13 (depends on 12) A method as defined in claim 12 wherein said liquid-penetrable material is gasket material. ### Claim 14 (depends on 12) A method as defined in claim 12 wherein said liquid dispersion of a polymer is a water dispersion of a polymer and wherein said water penetrable material is preheated to and maintained at a temperature of at least 125.degree. F. prior to coating. ### Claim 15 (depends on 12) A method as defined in claim 12 wherein said liquid-penetrable material is preheated to and maintained at a temperature between about 125.degree. F. and 250.degree. F. prior to coating. ### Claim 16 (depends on 12) A method as defined in claim 12 wherein said liquid-penetrable material is preheated to and maintained at a temperature of at least 150.degree. F. prior to coating. ### Claim 17 (depends on 12) A method as defined in claim 12 wherein said support members comprise a plurality of spaced polyurethane cords. ### Claim 18 A method of coating a liquid-penetrable material with a liquid dispersion of a polymer, comprising: preheating said liquid-penetrable material to a temperature sufficient to prevent any substantial penetration of liquid into said material when said material, at said preheated temperature, is contacted with a liquid dispersion of a polymer; maintaining said preheated material at a temperature sufficient to prevent any substantial penetration of liquid into said material when said material is contacted with a liquid dispersion of a polymer, until immediately prior to coating said material with a liquid dispersion of a polymer; coating a major surface of said preheated material with a liquid dispersion of a curable polymer in an amount sufficient to form a fluid impermeable barrier over said material after curing said coating; supporting said coated material on a plurality of suspension members through a drying station said suspension members having a material contact area sufficiently small that any depressions made in the polymer coating are healed over during curing; drying said coated material at said drying station in an amount sufficient to provide a tack-free polymer coating on said material; and curing said polymer coating. ### Claim 19 (depends on 18) A method as defined in claim 18 wherein said gasket suspension members in said drying station comprise elastomeric cords. ### Claim 20 (depends on 19) A method as defined in claim 19 wherein said elastomeric cords are polyurethane cords. ### Claim 21 (depends on 18) A method as defined in claim 18 wherein said liquid-penetrable material is gasket material. ### Claim 22 (depends on 18) A method as defined in claim 18 wherein said liquid dispersion of a polymer is a water dispersion of a polymer and wherein said water penetrable material is preheated to and maintained at a temperature of at least 135.degree. F. prior to coating. ### Claim 23 A method of coating a water-penetrable gasket material of the type comprising particulate material bound by an elastomer with a water dispersion of a polymer comprising: pre-heating said water-penetrable material to a temperature sufficient to prevent any substantial penetration of water into said material when said material, at said pre-heated temperature, is contacted with a water dispersion of a polymer; contacting a major surface of said pre-heated material while at said temperature with a water dispersion of a curable polymer; conveying said polymer contacted material to a drying station immediately after said polymer contact to prevent prolonged contact with said water so that said water does not substantially penetrable said pre-heated material; drying said coating; and curing said coating to form a polymer-coated article. ### Claim 24 (depends on 23) A method as defined in claim 23 wherein said water-penetrable material is preheated to and maintained at a temperature of at least 125.degree. F. prior to coating. ### Claim 25 (depends on 23) A method as defined in claim 23 further including supporting said water-penetrable material, after coating with said water dispersion, on raised support members contacting only one major surface of said coated material to convey the water dispersion coated material through a drying station such that said raised support members contact 30% or less of one major surface of said water-penetrable material while supporting said water-penetrable material substantially horizontally through said drying station. ### Claim 26 A method of coating a water-penetrable gasket material of the type comprising particulate material bound by an elastomer with a water dispersion of a polymer, comprising: preheating said water-penetrable material to a temperature sufficient to prevent any substantial penetration of water into said material when said material, at said preheated temperature, is contacted with a water dispersion of a polymer; maintaining said preheated material at a temperature sufficient to prevent any substantial penetration of water into said material when said material is contacted with a water dispersion of a polymer, until immediately prior to coating said material with a water dispersion of a polymer; contacting a major surface of said preheated material with a water dispersion of a curable polymer in an amount sufficient to form a fluid impermeable barrier coating over said material after curing said coating; conveying said coated material to a drying station immediately after contacting said material with said water dispersed polymer so that the water portion of the water dispersed polymer does not substantially penetrate the preheated material and to permit the water to be driven away from said preheated material as a result of the preheating; supporting said coated material on a plurality of raised gasket suspension members through the drying station in an amount sufficient to provide a tack-free polymer coating on said material, said suspension members having a material contact area sufficiently small that any depressions made in the polymer coating are healed over during curing; and curing said polymer coating. ### Claim 27 (depends on 26) A method as defined in claim 26 wherein said water-penetrable material is preheated to and maintained at a temperature of at least 135.degree. F. prior to coating. ### Claim 28 A method of coating a relatively flat, water penetrable gasket member composed of fibers and/or particulate, bound together by elastomer, said method comprising conveying said member flat-wise and successively through a pre-heating station, a coating station, a drying station, and a curing station, coating the member at the coating station with a water suspension of a curable polymer, applying at least 130.degree. F. preheat to the member as it is conveyed through the preheat station to prevent any substantial penetration of water into said preheated gasket member when said gasket member is contacted with a water suspension of a polymer, circulating air rapidly over the member as it leaves the coating station and while in the drying station to effectively dry the applied coating, controlling the amount of heat applied to the member in the pre-heat station and the speed at which the member is moved through the four stations so that the member when it reaches the coating station is not hot enough to cause curdling or coagulation of the coating material and so that the member after passing through the drying station and entering into the curing station does not blister, and then curing the coating. ### Claim 29 (depends on 28) The method as set forth in claim 28 in which the water suspension of the polymer comprises an emulsified reactive resin modified with synthetic elastomer latex. ### Claim 30 (depends on 28) The method as set forth in claim 28 in which the amount of pre-heat applied to the member in the pre-heat station is in the range between 130.degree. F. and 250.degree. F. and is sufficient to produce residual heat within the member as it passes through the coating station to prevent substantial penetration of the water in the polymer suspension into the gasket member, and to cause the polymer to be deposited on the surface of the gasket member as much of the water of the suspension is substantially instantaneously evaporated by the residual heat in gasket member. ### Claim 31 (depends on 28) A method as defined in claim 28 further including supporting said liguid-penetrable material, after coating with said liquid suspension, on raised support members contacting only one major surface of said coated material to convey the liquid suspension coated material through a drying station such that said raised support members contact 30% or less of one major surface of said liquid-penetrable material while supporting said liquid-penetrable material substantially horizontally through said drying station. ### Claim 32 (depends on 28) A method as defined in claim 28 including drying said liquid suspended coating for less than two minutes prior to curing said coating. ### Claim 33 (depends on 32) A method as defined in claim 32 wherein said coating is dried for one minute or less prior to curing said coating. ### Claim 34 (depends on 31) A method as defined in claim 31 wherein said raised support members include a plurality of rigid support members comprising two legs having an included angle therebetween of less than 180.degree., said two legs joining to form an elongated apex lying in a substantially horizontal plane when traveling through said drying station said apex including thereon a plurality of liquid-penetrable material support members. ### Claim 35 A method of fabricating gaskets and the like which comprises the steps of die cutting liquid penetrable compactible elastomeric material to a desired shape; heating said die cut material to a temperature of about 130.degree. to 250.degree. F. to substantially dehydrate the material; coating said material while at said temperature with a curable polymer dissolved or dispersed in a liquid which vaporizes within said 130.degree. to 250.degree. F. range, whereby the liquid is unable to substantially penetrate the material and the material is left with the polymer coating; and curing the coating. ### Claim 36 A method of coating a relatively flat, water penetrable, gasket member composed of fibers and/or particulate, bound together by an elastomer, said method comprising conveying said member flatwise to a coating station; heating said member prior to reaching the coating station and applying a coating to at least one side thereof, with the coating comprising a water suspension of a curable polymer, whereby the residual heat in said member as it passes through the coating station prevents substantial penetration of the water in the polymer suspension into the gasket member, and causes the polymer to be deposited on the surface of the gasket member as much of the water in the suspension is substantially instantaneously evaporated; and thereafter curing the coating. ### Claim 37 (depends on 36) A method as defined in claim 36 wherein the coating is simultaneously applied to both sides of the gasket member as it passes through the coating station. ### Claim 38 (depends on 36) A method as defined in claim 36 wherein the gasket member after coating is subjected to a further drying step after said substantially instantaneous evaporation and before curing.