# US 10,121,573 B2 · Epoxy-based resin system composition containing a latent functionality for polymer adhesion improvement to prevent sulfur related corrosion > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,121,573 B2 - Document ID: US10121573B2 - Status: Granted - Kind: B2 - Application number: 14/989,446 - Filed: 2016-01-06 - Published: 2017-07-06 - Granted: 2018-11-06 - Earliest claimed: 2016-01-06 - Assignees: International Business Machines Corporation - Applicants: International Business machines Corporation - Inventors: Dylan J. Boday; Joseph Kuczynski; Jason T. Wertz; Jing Zhang - Web page: https://patentgrep.com/patent/US10121573B2 ## CPC - H01C 1/032: plural layers surrounding the resistive element (H01C1/028 takes precedence) - C08K 9/04: Ingredients treated with organic substances {(treated with macromolecular compounds C08K9/08)} - C08K 13/06: Pretreated ingredients and ingredients covered by the main groups C08K3/00 - C08K7/00 - C09D 5/08: Anti-corrosive paints - C09D 5/082: {characterised by the anti-corrosive pigment} - C09D 7/62: modified by treatment with other compounds - C09D 7/65: macromolecular (C09D7/41-C09D7/48 take precedence) - H01C 17/02: adapted for manufacturing resistors with envelope or housing (apparatus or processes for filling or compressing insulating material in heating element tubes H05B3/52) - C08K 7/10: Silicon-containing compounds - C09D 163/00: Coating compositions based on epoxy resins; Coating compositions based on derivatives of epoxy resins - H01C 1/012: the base extending along and imparting rigidity or reinforcement to the resistive element (H01C1/016 takes precedence; the resistive element being formed in two or more coils or loops as a spiral, helical or toroidal winding H01C3/18, H01C3/20; the resistive element being formed as one or more layers or coatings on a base H01C7/00) - H01C: RESISTORS - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) - C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D) ## Abstract An epoxy-based resin system composition includes a latent functionality for polymer adhesion improvement. The composition may be used to produce an overcoat layer and/or protection layer in an anti-sulfur resistor (ASR). In some embodiments, the composition include epoxy-based resin(s), hardener(s) and, optionally, blowing agent(s) and/or filler(s). An epoxide functionality of one or more of the epoxy-based resin(s) and a reactive functionality of one or more of the hardener(s) react with each other at a first temperature. The latent functionality, which does not react at the first temperature, is contained in at least one of the epoxy-based resin(s), hardener(s) and filler(s) and reacts in response to another stimulus (e.g., UV light/initiator and/or a second temperature greater than the first temperature) to enhance chemical bonding. Optionally, voids created via etching and/or the blowing agent(s) may be used to enhance mechanical bonding, alone, or in combination with filler(s) exposed in the voids. ## Claims ### Claim 1 A method for producing an apparatus, comprising: providing an electronic component mounted on a substrate and electrically connected by metal conductors, wherein the metal conductors each have an upper termination layer with an upper surface; and covering at least a portion of the electronic component with an overcoat layer, wherein the overcoat layer overlies a first portion of the upper surface of the upper termination layer of the metal conductors and comprises an epoxy-based resin system; covering at least a portion of the overcoat layer with a protection layer, wherein the protection layer overlies a second portion of the upper surface of the upper termination layer of the metal conductors and comprises an epoxy-based resin system, wherein the overcoat layer and the protection layer together cover all of the upper surface of the upper termination layer of the metal conductors; wherein at least one of the overcoat layer and the protection layer is an epoxy-based resin system composition comprising: one or more epoxy-based resins, wherein at least one of the one or more epoxy-based resins includes a first epoxide functionality; one or more hardeners, wherein at least one of the one or more hardeners includes a first reactive functionality, and wherein the first reactive functionality and the first epoxide functionality react with each other at a first temperature; zero, one or more filler materials; wherein a latent functionality is contained in at least one of the one or more epoxy-based resins, the one or more hardeners, and the zero, one or more filler materials, wherein the latent functionality does not react at the first temperature, and wherein the latent functionality reacts in response to a stimulus comprising at least one of ultraviolet (UV) light and a second temperature greater than the first temperature. ### Claim 2 (depends on 1) The method as recited in claim 1, wherein the overcoat layer is the epoxy-based resin system composition, and wherein covering at least a portion of the electronic component with an overcoat layer comprises: applying the epoxy-based resin system composition in an at least partially uncured state over the electronic component, the metal conductors, and the substrate by dipping, spraying, spin-coating, casting, brushing, rolling, and/or syringe; and curing, at the first temperature, the epoxy-based resin system composition applied over the electronic component, metal conductors, and the substrate to thereby produce the overcoat layer. ### Claim 3 (depends on 2) The method as recited in claim 2, wherein the protection layer is an epoxy-based resin system formulation, and wherein covering at least a portion of the overcoat layer with a protection layer comprises: applying the epoxy-based resin system formulation in an at least partially uncured state over the overcoat layer, the metal conductors, and the substrate by dipping, spraying, spin-coating, casting, brushing, rolling, and/or syringe; and curing, via the stimulus, the epoxy-based resin system formulation applied over the overcoat layer, metal conductors, and the substrate to thereby produce the protection layer. ### Claim 4 (depends on 3) The method as recited in claim 3, further comprising: etching at least a portion of a surface of the overcoat layer to roughen the surface of the overcoat layer before applying the epoxy-based resin system formulation over the overcoat layer. ### Claim 5 (depends on 4) The method as recited in claim 4, wherein etching the overcoat layer includes exposing at least one of the zero, one or more filler materials on the surface of the overcoat layer. ### Claim 6 (depends on 5) The method as recited in claim 5, wherein the at least one of the zero, one or more filler materials includes at least one of silica fibers and silica particles surface modified to contain the latent functionality. ### Claim 7 (depends on 5) The method as recited in claim 5, wherein the at least one of the zero, one or more filler materials includes at least one of silica fibers and silica particles, the method further comprising: modifying a surface of the at least one of the zero, one or more filler materials to contain the latent functionality after etching the overcoat layer but before applying the epoxy-based resin system formulation over the overcoat layer. ### Claim 8 (depends on 3) The method as recited in claim 3, wherein the epoxy-based resin system composition further comprises a blowing agent, the method further comprising: activating the blowing agent to form voids on the surface of the overcoat layer before applying the epoxy-based resin system formulation in the at least partially uncured state over the overcoat layer. ### Claim 9 (depends on 8) The method as recited in claim 8, wherein activating the blowing agent to form voids on the surface of the overcoat layer includes exposing at least one of the zero, one or more filler materials on the surface of the overcoat layer. ### Claim 10 (depends on 9) The method as recited in claim 9, wherein the at least one of the zero, one or more filler materials includes at least one of silica fibers and silica particles surface modified to contain the latent functionality. ### Claim 11 (depends on 9) The method as recited in claim 9, wherein the at least one of the zero, one or more filler materials includes at least one of silica fibers and silica particles, the method further comprising: modifying a surface of the at least one of the zero, one or more filler materials to contain the latent functionality after activating the blowing agent to form voids on the surface of the overcoat layer but before applying the epoxy-based resin system formulation over the overcoat layer. ### Claim 12 (depends on 1) The method as recited in claim 1, wherein at least one of the one or more hardeners contains the latent functionality, wherein the first reactive functionality of the at least one of the one or more hardeners that includes the first reactive functionality is a primary amine, and wherein the latent functionality of the at least one of the one or more hardeners that contains the latent functionality is a secondary amine. ### Claim 13 (depends on 1) The method as recited in claim 1, wherein the at least one of the one or more hardeners that includes the first reactive functionality also contains the latent functionality, wherein the first reactive functionality of the least one of the one or more hardeners is a primary amine, and wherein the latent functionality of the at least one of the one or more hardeners is a secondary amine. ### Claim 14 (depends on 1) The method as recited in claim 1, wherein at least one of the one or more epoxy-based resins contains the latent functionality, wherein the at least one of the one or more epoxy-based resins that contains the latent functionality is a cycloaliphatic epoxy resin, and wherein the at least one of the one or more epoxy-based resins that includes the first epoxide functionality is selected from a group consisting of bisphenol A epoxy resin, bisphenol F epoxy resin, novalac epoxy resin, aliphatic epoxy resin, glycidylamine epoxy resin, phenyl glycidyl ether, and combinations thereof. ### Claim 15 (depends on 1) The method as recited in claim 1, wherein the one or more hardeners includes an onium salt as a UV initiator. ### Claim 16 An apparatus, comprising: a substrate; an electronic component mounted on the substrate; metal conductors electrically connecting the electronic component, wherein the metal conductors each have an upper termination layer with an upper surface; and an overcoat layer covering at least a portion of the electronic component, wherein the overcoat layer overlies a first portion of the upper surface of the upper termination layer of the metal conductors and comprises a cured epoxy resin; a protection layer covering at least a portion of the overcoat layer, wherein the protection layer overlies a second portion of the upper surface of the upper termination layer of the metal conductors and comprises a cured epoxy resin, wherein the overcoat layer and the protection layer together cover all of the upper surface of the upper termination layer of the metal conductors; wherein at least one of the overcoat layer and the protection layer is formed from an epoxy-based resin system composition comprising: one or more epoxy-based resins, wherein at least one of the one or more epoxy-based resins includes a first epoxide functionality; one or more hardeners, wherein at least one of the one or more hardeners includes a first reactive functionality, and wherein the first reactive functionality and the first epoxide functionality react with each other at a first temperature; zero, one or more filler materials; wherein a latent functionality is contained in at least one of the one or more epoxy-based resins, the one or more hardeners, and the zero, one or more filler materials, wherein the latent functionality does not react at the first temperature, and wherein the latent functionality reacts in response to a stimulus comprising at least one of ultraviolet (UV) light and a second temperature greater than the first temperature. ### Claim 17 (depends on 16) The apparatus as recited in claim 16, wherein the overcoat layer and the protection layer are exposed to, and protect the metal conductors from, a gaseous environment that includes elemental sulfur, hydrogen sulfide, and/or sulfur oxides, and wherein the metal conductors comprise silver. ### Claim 18 (depends on 17) The apparatus as recited in claim 17, wherein the electronic component is an anti-sulfur resistor (ASR) of a resistor network array, and wherein the metal conductors comprise an upper termination of the ASR.