# US 2025/0084263 A1 · Ink for forming coating film of optical member, and optical member > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0084263 A1 - Document ID: US20250084263A1 - Status: Published application - Kind: A1 - Application number: 18/822,305 - Filed: 2024-09-02 - Published: 2025-03-13 - Earliest claimed: 2023-09-12 - Assignees: FUJIFILM Corporation - Applicants: Fujifilm Corporation - Inventors: Goroh TAKADA - Web page: https://patentgrep.com/patent/US20250084263A1 ## CPC - C09D 11/037: characterised by the pigment - G02B 1/11: Anti-reflection coatings - 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) - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract Provided are an ink for forming a coating film of an optical member, containing a black pigment, at least one of a colored pigment or a colorless pigment, a binder, and a volatile component, in which, in a case of forming a coating film of an optical member, an average refractive index n of the coating film of an optical member in a wavelength range of 400 nm to 700 nm is 1.70 or more, and an average attenuation coefficient k of the coating film of an optical member in the wavelength range of 400 nm to 700 nm is 0.10 to 0.15, and a total ratio of the black pigment, the colored pigment, and the colorless pigment in an entire volume of the coating film of an optical member is 10% by volume to 40% by volume; and an application thereof. ## Claims ### Claim 1 An ink for forming a coating film of an optical member, comprising: a black pigment; at least one of a colored pigment or a colorless pigment; a binder; and a volatile component, wherein, in a case of forming a coating film of an optical member, an average refractive index n of the coating film of an optical member in a wavelength range of 400 nm to 700 nm is 1.60 or more, and an average attenuation coefficient k of the coating film of an optical member in the wavelength range of 400 nm to 700 nm is 0.10 to 0.15, and a total volume ratio of the black pigment, the colored pigment, and the colorless pigment in an entire volume of the coating film of an optical member is 10% by volume to 40% by volume. ### Claim 2 (depends on 1) The ink for forming a coating film of an optical member according to claim 1, wherein the average refractive index n of the coating film of an optical member in the wavelength range of 400 nm to 700 nm is 1.70 to 1.85. ### Claim 3 (depends on 1) The ink for forming a coating film of an optical member according to claim 1, wherein, with regard to each of the black pigment, the colored pigment, and the colorless pigment, the average refractive index n in the wavelength range of 400 nm to 700 nm is 2.00 or more, and with regard to each of the black pigment and the colored pigment, the average attenuation coefficient k is 0.10 or more. ### Claim 4 (depends on 1) The ink for forming a coating film of an optical member according to claim 1, wherein the black pigment includes at least one selected from the group consisting of carbon black and titanium carbide, the colored pigment includes at least one selected from the group consisting of iron oxide (III), silicon carbide, and copper oxide (I), and the colorless pigment includes at least one selected from the group consisting of titanium oxide, diamond, zirconia, and indium tin oxide. ### Claim 5 (depends on 1) The ink for forming a coating film of an optical member according to claim 1, wherein a median diameter of the pigments is 100 nm or less. ### Claim 6 (depends on 1) The ink for forming a coating film of an optical member according to claim 1, wherein the binder contains an epoxy resin in which the average refractive index n in the wavelength range of 400 nm to 700 nm is 1.60 or more. ### Claim 7 (depends on 6) The ink for forming a coating film of an optical member according to claim 6, wherein the epoxy resin includes a fluorene-based epoxy resin. ### Claim 8 (depends on 6) The ink for forming a coating film of an optical member according to claim 6, wherein the epoxy resin includes a thermosetting type epoxy resin. ### Claim 9 (depends on 8) The ink for forming a coating film of an optical member according to claim 8, further comprising: a thiol-based curing agent as a curing agent for an epoxy resin; and a tertiary amine as a curing accelerator. ### Claim 10 (depends on 1) The ink for forming a coating film of an optical member according to claim 1, wherein a content of the volatile component is 50% by mass or more with respect to a total amount of the ink for forming a coating film of an optical member. ### Claim 11 (depends on 1) The ink for forming a coating film of an optical member according to claim 1, wherein the volatile component includes an organic solvent having a boiling point of 180° C. or lower. ### Claim 12 (depends on 1) The ink for forming a coating film of an optical member according to claim 1, wherein the volatile component includes at least one selected from the group consisting of propyl acetate, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, toluene, cyclohexane, and ethylene glycol monobutyl ether. ### Claim 13 (depends on 1) The ink for forming a coating film of an optical member according to claim 1, further comprising a silane coupling agent. ### Claim 14 (depends on 1) The ink for forming a coating film of an optical member according to claim 1, further comprising a filler. ### Claim 15 An ink for forming a coating film of an optical member, comprising: a black pigment; at least one of a colored pigment or a colorless pigment; a binder; and a volatile component, wherein, with regard to each of the black pigment, the colored pigment, and the colorless pigment, an average refractive index n in a wavelength range of 400 nm to 700 nm is 2.00 or more, with regard to each of the black pigment and the colored pigment, an average attenuation coefficient k is 0.10 or more, and a total mass ratio of the black pigment, the colored pigment, and the colorless pigment in a total solid content is 6.5% by mass to 25.8% by mass. ### Claim 16 (depends on 15) The ink for forming a coating film of an optical member according to claim 15, wherein the black pigment includes at least one selected from the group consisting of carbon black and titanium carbide, the colored pigment includes at least one selected from the group consisting of iron oxide (III), silicon carbide, and copper oxide (I), and the colorless pigment includes at least one selected from the group consisting of titanium oxide, diamond, zirconia, and indium tin oxide. ### Claim 17 (depends on 15) The ink for forming a coating film of an optical member according to claim 15, wherein a median diameter of the pigments is 100 nm or less. ### Claim 18 (depends on 15) The ink for forming a coating film of an optical member according to claim 15, wherein the binder contains an epoxy resin in which the average refractive index n in the wavelength range of 400 nm to 700 nm is 1.60 or more. ### Claim 19 (depends on 18) The ink for forming a coating film of an optical member according to claim 18, wherein the epoxy resin includes a fluorene-based epoxy resin. ### Claim 20 (depends on 18) The ink for forming a coating film of an optical member according to claim 18, wherein the epoxy resin includes a thermosetting type epoxy resin. ### Claim 21 (depends on 20) The ink for forming a coating film of an optical member according to claim 20, further comprising: a thiol-based curing agent as a curing agent for an epoxy resin; and a tertiary amine as a curing accelerator. ### Claim 22 (depends on 15) The ink for forming a coating film of an optical member according to claim 15, wherein a content of the volatile component is 50% by mass or more with respect to a total amount of the ink for forming a coating film of an optical member. ### Claim 23 (depends on 15) The ink for forming a coating film of an optical member according to claim 15, wherein the volatile component includes at least one selected from the group consisting of propyl acetate, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, toluene, cyclohexane, and ethylene glycol monobutyl ether. ### Claim 24 (depends on 15) The ink for forming a coating film of an optical member according to claim 15, further comprising a silane coupling agent. ### Claim 25 (depends on 15) The ink for forming a coating film of an optical member according to claim 15, further comprising a filler. ### Claim 26 An optical member comprising: a base material of an optical member; and a coating film of an optical member, provided on a part of the base material of an optical member, wherein the coating film of an optical member contains a black pigment and at least one of a colored pigment or a colorless pigment, an average refractive index n of the coating film of an optical member in a wavelength range of 400 nm to 700 nm is 1.70 or more, and an average attenuation coefficient k of the coating film of an optical member in the wavelength range of 400 nm to 700 nm is 0.10 to 0.15, and a total ratio of the black pigment, the colored pigment, and the colorless pigment in an entire volume of the coating film of an optical member is 10% by volume to 40% by volume. ### Claim 27 (depends on 26) The optical member according to claim 26, wherein the optical member is an optical member for broadcasting, an optical member for cinema, an optical member for a digital camera, an optical member for an industrial camera, an optical member for a projector, an optical member for a vehicle-mounted camera, an optical member for a smartphone-mounted camera, an optical member using a prism, or an optical member using an optical waveguide.