# US 5,705,219 A · Method for coating surfaces with finely particulate materials > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,705,219 A - Document ID: US5705219A - Status: Granted - Kind: A - Application number: 08/616,110 - Filed: 1996-03-14 - Granted: 1998-01-06 - Earliest claimed: 1991-04-22 - Assignees: Atotech Deutschland GmbH - Inventors: Jurgen-Otto Besenhard; Olaf Claussen; Hans-Peter Gausmann; Heinrich Meyer; Hartmut Mahlkow - Web page: https://patentgrep.com/patent/US5705219A ## CPC - C25D 5/56: of plastics - B05D 1/18: performed by dipping - B05D 3/005: {Pretreatment for allowing a non-conductive substrate to be electrostatically coated} - C23C 18/1893: {with use of organic or inorganic compounds other than metals, first} - C23C 18/2086: {with use of organic or inorganic compounds other than metals, first} - C23C 18/30: Activating {or accelerating or sensitising with palladium or other noble metal} - H01B 1/22: the conductive material comprising metals or alloys - H01B 1/24: the conductive material comprising carbon-silicon compounds, carbon or silicon - H05K 3/424: {by direct electroplating} - B05D 7/142: {Auto-deposited coatings, i.e. autophoretic coatings} - H05K 2201/0323: Carbon - H05K 2203/122: Organic non-polymeric compounds, e.g. oil, wax or thiol - C25D: PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR - B05D: PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL (conveying articles or workpieces through baths of liquid B65G, e.g. B65G49/02) - C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04) - H01B: CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES (selection for magnetic properties H01F1/00; waveguides H01P {; printed circuits H05K}) - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS ## Abstract A method for coating surfaces of a non-conductor with finely particulate solid particles by substrate-induced coagulation, including the steps of: contacting the non-conductor with a first solution containing a first polar solvent and at least one coagulation initiator comprising high molecular weight material; and, subsequently contacting the non-conductor with a dispersion which contains a second polar solvent and: a) finely particulate solid particles, b) at least one surfactant for preventing the sedimentation of the solid particles, and c) a salt, essentially free of tin ions, for selectively destabilizing the dispersion. ## Claims ### Claim 1 A method of coating a surface of a nonconductor substrate with particulate solid particles by substrate-induced coagulation, comprising steps of: (a) treating the nonconductor substrate with a first solution containing a first polar solvent and at least one coagulation initiator comprising a soluble polymer so that the coagulation initiator adheres to the substrate; and, (b) subsequently coagulating the particulate solid particles on the non-conductor substrate by contacting the substrate treated in step (a) with a dispersion containing a second polar solvent and: i) the particulate solid particles, ii) at least one surfactant for preventing sedimentation of the solid particles prior to the coagulation, and iii) a salt for promoting destabilization of the dispersion during the coagulation, and wherein the first and second polar solvent are the same or different. ### Claim 2 (depends on 1) The method of claim 1, wherein the solid particles are electron-conducting solid particles. ### Claim 3 (depends on 1) The method of claim 1, wherein the solid particles are selected from the group consisting of graphite and carbon black. ### Claim 4 (depends on 2) The method of claim 2, wherein the non-conductor surface is coated with the electron-conducting solid particles in an amount sufficient to permit a subsequent galvanic deposition of metal. ### Claim 5 (depends on 1) The method of claim 1, wherein the soluble polymer is selected from the group consisting of water-soluble proteins and polysaccharides. ### Claim 6 (depends on 1) The method of claim 1, wherein the soluble polymer comprises a natural product or derivative thereof selected from the group consisting of soluble proteins and polysaccharides. ### Claim 7 (depends on 1) The method of claim 1, wherein the soluble polymer is a soluble synthetic polymer. ### Claim 8 (depends on 1) The method of claim 1, wherein the soluble polymer is selected from the group consisting of polyelectrolytes with a positive or negative charge and betaines which simultaneously carry positive and negative charges. ### Claim 9 (depends on 1) The method of claim 1, wherein the surfactant for preventing the sedimentation of the solid particles is selected from the group consisting of anionic, cationic, amphoteric and nonionic surfactants. ### Claim 10 (depends on 1) The method of claim 1, wherein the salt contained in the dispersion is selected from the group consisting of halides, borates, carbonates, nitrates, phosphates, sulfates, acetates and chlorates of inorganic monovalent, divalent and trivalent cations. ### Claim 11 (depends on 1) The method of claim 1, wherein the nonconductor substrate is selected from the group consisting of synthetic resins and composites thereof. ### Claim 12 (depends on 11) The method of claim 11, wherein the synthetic resins are selected from the group consisting of epoxide resins, polyimide resins and polytetrafluoroethylene and the composites are reinforced with glass fibers. ### Claim 13 (depends on 1) The method of claim 1, wherein the solid particles are applied on a wall of an electronic component and comprising an additional step of depositing a metal on the wall after the coagulation of the solid particles. ### Claim 14 (depends on 1) The method of claim 1, wherein the solid particles are applied on a wall of a borehole in a printed circuit board and comprising an additional step of galvanically depositing a metal on the wall after the coagulation of the solid particles. ### Claim 15 (depends on 14) The method of claim 14, wherein the circuit boards are multilayer printed circuit boards. ### Claim 16 (depends on 1) The method of claim 1, wherein the first solution contains a bactericidal substance. ### Claim 17 (depends on 1) The method of claim 1, wherein the step of contacting the nonconductor substrate with the dispersion includes contacting with a dispersion having one of anionic surfactants, cationic surfactants and phase-transfer catalysts as a wetting agent. ### Claim 18 (depends on 1) The method of claim 1, wherein the substrate comprises a copper surface adjacent nonconductor surface and further including a step of treating the nonconductor surface prior to step (b) with a copper (II) solution. ### Claim 19 (depends on 1) The method of claim 1, wherein the salt comprises one of fluorides, chlorides, bromides and iodides of one of lithium, sodium, potassium, ammonium, magnesium, calcium, barium, strontium, and copper. ### Claim 20 (depends on 3) The method of claim 3, wherein the solid particles are selected from the group consisting of the graphite with an average particle size less than 50 .mu.m and the carbon black with an average particle size less than 5 .mu.m. ### Claim 21 (depends on 1) The method of claim 1, and further comprising steps of rinsing the nonconductor substrate after the coagulating step, drying the nonconductor substrate, coated with the particulate solid particles, after the rinsing step, and then galvanically metallizing the nonconductor substrate. ### Claim 22 (depends on 21) The method of claim 21, wherein the nonconductor substrate comprises a copper surface and further including a step of etching the copper surface, coated with the particulate solid particles, with a copper etching solution before said drying step. ### Claim 23 (depends on 1) The method of claim 1, comprising an additional step of rinsing the nonconductor substrate after step (a) and prior to performing step (b).