# US 2024/0201519 A1 · Photochromic lens with bifocal film layer and preparation method for photochromic lens > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2024/0201519 A1 - Document ID: US20240201519A1 - Status: Published application - Kind: A1 - Application number: 18/288,917 - Filed: 2021-06-02 - Published: 2024-06-20 - Earliest claimed: 2021-04-30 - Assignees: Jiangsu Maat Optical Technology Co., Ltd. - Applicants: Jiangsu Maat Optical Technology Co., Ltd. - Inventors: Jun Li; Jianguo Shang - Web page: https://patentgrep.com/patent/US20240201519A1 ## CPC - G02C 7/102: {Photochromic filters} - B29D 11/00028: {Bifocal lenses; Multifocal lenses} - B29D 11/00413: {made by moulding between two mould parts which are not in direct contact with one another, e.g. comprising a seal between or on the edges (B29D11/00019 - B29D11/00355, B29D11/00423, B29D11/00432 take precedence)} - B29D 11/00653: {photochromic} - B29D 11/0073: {Optical laminates} - B29D 11/00884: {Spin coating} - C09D 7/63: organic - C09D 163/10: Epoxy resins modified by unsaturated compounds - G02C 7/06: bifocal; multifocal {; progressive (G02C7/041 takes precedence)} - G02C: SPECTACLES; SUNGLASSES OR GOGGLES INSOFAR AS THEY HAVE THE SAME FEATURES AS SPECTACLES; CONTACT LENSES (trial frames for testing the eyes A61B3/04; goggles or eyeshields not having the same features as spectacles A61F9/00) - B29D: PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE (making granules B29B9/00; making preforms B29B11/00) - 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 The present disclosure relates to a preparation method for a photochromic lens with a bifocal film layer. A photochromic lens with a bifocal film layer includes a substrate, a treatment layer, and a photochromic layer from inside to outside, where the photochromic layer is cured on a surface of the treatment layer by means of ultraviolet irradiation. According to the preparation method for a photochromic lens having a bifocal film layer provided in the present disclosure, a bifocal lens is used as a lens substrate, and photochromic and bifocal technologies are combined to overcome the defect of non-uniformity of a bifocal film layer caused by a spin-coating method, such that a photochromic layer can be uniformly attached to a surface of the lens substrate. Thus, uniform photochromism and excellent performance are achieved, and it can be ensured that the surface shape luminosity of the bifocal lens substrate is not affected. ## Claims ### Claim 1 A photochromic lens with a bifocal film layer, comprising a substrate (1), a treatment layer (2) and a photochromic layer (3) from inside to outside, wherein the photochromic layer (3) is cured on a surface of the treatment layer (2) by means of ultraviolet irradiation, and the substrate (1) is an E-line bifocal lens or a flat-top bifocal lens. ### Claim 2 (depends on 1) The photochromic lens with a bifocal film layer according to claim 1, wherein the substrate (1) comprises a main lens (11) and a segment lens (12), the main lens (11) is a distance-viewing structure, and the segment lens (12) is a near-viewing part. ### Claim 3 (depends on 1) The photochromic lens with a bifocal film layer according to claim 1, wherein materials of the treatment layer (2) comprise the following components in parts by weight: 50-80 parts of bisphenol A epoxy acrylic resin, 5-8 parts of dioctyl adipate, 2-5 parts of vinyl trimethoxy silane, and 1-3 parts of tetrabutylammonium chloride. ### Claim 4 (depends on 1) The photochromic lens with a bifocal film layer according to claim 1, wherein the photochromic layer (3) comprises the following components in mass fraction: 30%-70% of bisphenol A dimethacrylate, 10%-60% of poly(ethylene glycol) diacrylate, 10%-30% of polyfunctional acrylate monomer, and the rest of photoinitiator, with a total of 100%. ### Claim 5 (depends on 1) The photochromic lens with a bifocal film layer according to claim 1, wherein a transparent polymer material for optics is any one of polycarbonate, polymethylmethacrylate, or polymer alloy. ### Claim 6 (depends on 1) A preparation method for the photochromic lens with a bifocal film layer according to claim 1, comprising the following operation steps: S1: uniformly spin-coating a treatment layer (2) on surface of a substrate (1); S2: placing the substrate (1) obtained in Step S1 in an external mold adapted to a shape and structure of the substrate (1), reserving a gap between the external mold and the substrate (1), and fixing the external and the substrate with an adhesive tape; S3: injecting a photochromic material into the gap of Step S2 to fill and seal the gap; S4: curing the photochromic material by means of ultraviolet irradiation to form a photochromic layer (3); and S5: demolding to obtain the photochromic material with a bifocal film layer. ### Claim 7 (depends on 6) The preparation method for the photochromic lens with a bifocal film layer according to claim 6, comprising the following operation steps: S1: uniformly spin-coating the treatment layer (2) on the surface of the substrate (1); S2: placing the substrate (1) obtained in Step S1 in the external mold adapted to the shape and structure of the substrate (1), reserving a gap of 5 mm between the external mold and the substrate (1), and fixing the external and the substrate with an adhesive tape; S3: injecting the photochromic material into the gap of Step S2, adjusting the gap to 4 mm when the photochromic material is filled to ½-⅔ of the volume of the gap, wherein the gap is a thickness of the photochromic layer, and continuously injecting the photochromic material until the gap is filled and sealed with the photochromic material; S4: curing the photochromic material by means of ultraviolet irradiation for 2 min to form the photochromic layer (3); and S5: demolding to obtain the photochromic material with a bifocal film layer. ### Claim 8 (depends on 7) The preparation method for the photochromic lens with a bifocal film layer according to claim 7, wherein in Step S1, the treatment layer (2) is uniformly spin-coated on the surface of the substrate (1), and the substrate coated with the treatment layer (2) is irradiated with an ultraviolet curing light source for 1 min. ### Claim 9 (depends on 8) The preparation method for the photochromic lens with a bifocal film layer according to claim 8, wherein in Step S3, an injection hole is punched in the adhesive tape, the photochromic material is injected into the gap through the injection hole with a syringe, and then the hole is sealed with the adhesive tape. ### Claim 10 (depends on 8) The preparation method for the photochromic lens with a bifocal film layer according to claim 8, wherein in Step S3, a vent hole is punched in the adhesive tape, and the vent hole is adjacent to the injection hole; when the photochromic material overflows from the vent hole, the gap is determined to be filled with the photochromic material.