# US 12,111,485 B2 · Textured coating for optical products > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,111,485 B2 - Document ID: US12111485B2 - Status: Granted - Kind: B2 - Application number: 17/332,477 - Filed: 2021-05-27 - Published: 2021-09-30 - Granted: 2024-10-08 - Earliest claimed: 2014-04-25 - Assignees: 3M Innovative Properties Company - Applicants: 3M Innovative Properties Company - Inventors: Thomas J. Ludemann; Jeffrey W. Hagen; David T. Ask; Kristy A Gillette; Eric D. Shockey - Web page: https://patentgrep.com/patent/US12111485B2 ## CPC - G02B 5/0268: {characterized by the fabrication or manufacturing method} - B05D 1/28: performed by transfer from the surfaces of elements carrying the liquid or other fluent material, e.g. brushes, pads, rollers - B05D 1/305: {Curtain coating} - G02B 1/10: Optical coatings produced by application to, or surface treatment of, optical elements (G02B1/08 takes precedence) - G02B 5/021: {the diffusion taking place at the element's surface, e.g. by means of surface roughening or microprismatic structures} - G02B 5/0221: {the surface having an irregular structure (G02B5/0226 takes precedence)} - G02B 5/0278: {used in transmission} - G02B 27/0025: {for optical correction, e.g. distorsion, aberration} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - B05D: PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL (conveying articles or workpieces through baths of liquid B65G, e.g. B65G49/02) ## Abstract A coating composition includes a first polymer and a second polymer that are incompatible and non-reactive with one another. The absolute value of the difference between the refractive index of the first polymer and the refractive index of the second polymer is about 0 to about 0.01. The first polymer and the second polymer are soluble in a carrier liquid that is a good solvent for the first polymer and a poor solvent for the second polymer. The carrier liquid is removed from the coating layer to spinodally decompose the mixture of the first polymer and the second polymer in an amount sufficient to form a substantially continuous first phase with a predominant amount of the first polymer and a substantially discontinuous second phase with a predominant amount the second polymer. At least 70% of the second phase includes droplets with an aspect ratio, when viewed in the plane of the surface of the substrate, of less than about 3. ## Claims ### Claim 1 An optical element comprising: a light transmissive substrate; and a continuous coating on the substrate, wherein the coating comprises: a first region comprising a first polymer selected from cellulose resins and (meth)acrylic resins; and a second region comprising a second polymer different from the first polymer, wherein the second polymer is selected from cellulose resins and (meth)acrylic resins; wherein the first polymer and the second polymer are incompatible and non-reactive with one another, wherein the absolute value of the difference between the refractive index of the first polymer and the refractive index of the second polymer is from about 0 to about 0.01, wherein the first regions have a thickness different from the second regions, wherein the ratio by weight of the first polymer to the second polymer is from 1:2 to 10:1, and wherein the second regions project away from a surface of the substrate to a height of about 0.1 μm to about 15 μm above the height of the first regions. ### Claim 2 (depends on 1) The optical element of claim 1, wherein the first polymer and the second polymer comprise cellulose resins. ### Claim 3 (depends on 2) The optical element of claim 2, wherein the first polymer and the second polymer comprise one or more of cellulose acetate, cellulose acetate butyrate, and cellulose acetate propionate. ### Claim 4 (depends on 3) The optical element of claim 3, wherein the first polymer and the second polymer comprise one or more of cellulose acetate and cellulose acetate butyrate. ### Claim 5 (depends on 4) The optical element of claim 4, wherein at least 35% of the regions in the coating comprise cellulose acetate butyrate. ### Claim 6 (depends on 1) The optical element of claim 1, wherein the ratio of the first regions to the second regions in the coating is about 1:1. ### Claim 7 (depends on 1) The optical element of claim 1, wherein the coating has an RMS roughness of about 0.01 μm to about 2.0 μm. ### Claim 8 (depends on 1) The optical element of claim 1, wherein the bulk haze of the coating as measured after planarizing the substrate is less than about 1.0. ### Claim 9 (depends on 1) The optical element of claim 1, wherein the wherein the absolute value of the difference between the refractive index of the first polymer and the refractive index of the second polymer is about 0 to about 0.005. ### Claim 10 (depends on 1) The optical element of claim 1, wherein the coating has a haze of about 1% to about 99%. ### Claim 11 (depends on 1) The optical element of claim 1, wherein the coating has a clarity of about 5% to about 98%. ### Claim 12 (depends on 1) The optical element of claim 1, wherein the coating has a haze and a clarity both less than about 50%. ### Claim 13 An optical element comprising: a light transmissive substrate; and a continuous coating on the substrate, wherein the coating comprises: a first region comprising a first polymer selected from cellulose resins and (meth)acrylic resins; and a second region comprising a second polymer different from the first polymer, wherein the second polymer is selected from cellulose resins and (meth)acrylic resins; and a third polymer compatible with at least one of the first and the second polymers, wherein the first polymer and the second polymer are incompatible and non-reactive with one another, wherein the absolute value of the difference between the refractive index of the first polymer and the refractive index of the second polymer is from about 0 to about 0.01, and wherein the first regions have a thickness different from the second regions. ### Claim 14 An optical element comprising: a light transmissive substrate; and a continuous coating on the substrate, wherein the coating comprises: a first region comprising a first polymer selected from cellulose resins and (meth)acrylic resins; and a second region comprising a second polymer different from the first polymer, wherein the second polymer is selected from cellulose resins and (meth)acrylic resins; wherein the first polymer and the second polymer are incompatible and non-reactive with one another, wherein the absolute value of the difference between the refractive index of the first polymer and the refractive index of the second polymer is from about 0 to about 0.01, wherein the first regions have a thickness different from the second regions, wherein the ratio by weight of the first polymer to the second polymer is from 1:2 to 10:1, and wherein the effective transmission of the coating is at least 1.1.