# US 8,771,409 B2 · Electroless gold plating solution and electroless gold plating method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,771,409 B2 - Document ID: US8771409B2 - Status: Granted - Kind: B2 - Application number: 13/388,752 - Filed: 2011-04-15 - Published: 2012-05-24 - Granted: 2014-07-08 - Earliest claimed: 2010-07-20 - Assignees: Electroplating Engineers of Japan Limited - Applicants: Takanobu Asakawa; Tomoyuki Fujinami - Inventors: Takanobu Asakawa; Tomoyuki Fujinami - Web page: https://patentgrep.com/patent/US8771409B2 ## CPC - C23C 18/44: using reducing agents - C23C 18/1637: {metallic substrate} - Y10T 428/12889: Au-base component - 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) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract It is an object of the present invention to provide an electroless gold plating solution capable of directly subjecting a plated coating film made of an underlying metal such as nickel or palladium to gold plate processing, of forming a thick gold plated coating film having a thickness of 0.1 μm or more, of forming a uniform gold plated coating film, and of safely performing plating work. The present invention relates to an electroless gold plating solution comprising: a water-soluble gold compound; and hexahydro-2,4,6-trimethyl-1,3,5-triazine or hexamethylenetetramine. Preferably, the electroless gold plating solution comprises 0.1 to 100 g/L of hexahydro-2,4,6-trimethyl-1,3,5-triazine or hexamethylenetetramine. ## Claims ### Claim 1 An electroless gold plating solution comprising: a water-soluble gold compound; and hexahydro-2,4,6-trimethyl-1,3,5-triazine. ### Claim 2 (depends on 1) The electroless gold plating solution according to claim 1, comprising a complexing agent for gold. ### Claim 3 (depends on 1) The electroless gold plating solution according to claim 1, comprising an amine compound. ### Claim 4 (depends on 1) The electroless gold plating solution according to claim 1, comprising 0.1 to 100 g/L of hexahydro-2,4,6-trimethyl-1,3,5-triazine. ### Claim 5 (depends on 3) The electroless gold plating solution according to claim 3, comprising 0.1 to 100 g/L of the amine compound. ### Claim 6 (depends on 1) An electroless gold plating method comprising the step of subjecting a metallic surface of a substrate to electroless gold plate processing with the electroless gold plating solution according to claim 1. ### Claim 7 (depends on 6) An electronic component comprising a joined part subjected to an electroless gold plate processing by the electroless gold plating method according to claim 6. ### Claim 8 (depends on 2) The electroless gold plating solution according to claim 2, comprising an amine compound. ### Claim 9 (depends on 2) The electroless gold plating solution according to claim 2 comprising 0.1 to 100 g/L of hexahydro-2,4,6-trimethyl-1,3,5-triazine. ### Claim 10 (depends on 3) The electroless gold plating solution according to claim 3 comprising 0.1 to 100 g/L of hexahydro-2,4,6-trimethyl-1,3,5-triazine. ### Claim 11 (depends on 8) The electroless gold plating solution according to claim 8 comprising 0.1 to 100 g/L of hexahydro-2,4,6-trimethyl-1,3,5-triazine. ### Claim 12 (depends on 8) The electroless gold plating solution according to claim 8, comprising 0.1 to 100 g/L of the amine compound. ### Claim 13 (depends on 4) The electroless gold plating solution according to claim 4, comprising 0.1 to 100 g/L of the amine compound. ### Claim 14 (depends on 9) The electroless gold plating solution according to claim 9, comprising 0.1 to 100 g/L of the amine compound. ### Claim 15 (depends on 10) The electroless gold plating solution according to claim 10, comprising 0.1 to 100 g/L of the amine compound. ### Claim 16 (depends on 1) The electroless gold plating solution according to claim 1, comprising 0.1 to 100 g/L of the amine compound. ### Claim 17 (depends on 2) An electroless gold plating method comprising the step of subjecting a metallic surface of a substrate to electroless gold plate processing with the electroless gold plating solution according to claim 2. ### Claim 18 (depends on 3) An electroless gold plating method comprising the step of subjecting a metallic surface of a substrate to electroless gold plate processing with the electroless gold plating solution according to claim 3. ### Claim 19 (depends on 4) An electroless gold plating method comprising the step of subjecting a metallic surface of a substrate to electroless gold plate processing with the electroless gold plating solution according to claim 4. ### Claim 20 (depends on 5) An electroless gold plating method comprising the step of subjecting a metallic surface of a substrate to electroless gold plate processing with the electroless gold plating solution according to claim 5.