# US 11,110,649 B2 · Additively manufactured products having a matte surface finish > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,110,649 B2 - Document ID: US11110649B2 - Status: Granted - Kind: B2 - Application number: 17/058,288 - Filed: 2019-11-22 - Published: 2021-07-08 - Granted: 2021-09-07 - Earliest claimed: 2019-01-04 - Assignees: Carbon, Inc. - Applicants: Carbon, Inc. - Inventors: Bob E. Feller - Web page: https://patentgrep.com/patent/US11110649B2 ## CPC - B29C 64/129: characterised by the energy source therefor, e.g. by global irradiation combined with a mask - B29C 64/10: Processes of additive manufacturing - B33Y 10/00: Processes of additive manufacturing - C08K 3/013: Fillers, pigments or reinforcing additives - C08K 5/0041: {Optical brightening agents, organic pigments} - B29K 2075/00: Use of {PU, i.e.} polyureas or polyurethanes {or derivatives thereof}, as moulding material - B29K 2105/0032: {Pigments, colouring agents or opacifiyng agents} - B29K 2995/0025: Opaque - B29L 2031/504: {Soles} - B33Y 80/00: Products made by additive manufacturing - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - B33Y: ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) - B29K: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR {MOULDS, } REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS - B29L: INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES ## Abstract Provided herein is a method of making an object having a matte surface finish by stereolithography. The method may include: (a) stereolithographically producing an intermediate object by polymerization of a dual cure resin with a first light having a first peak wavelength, the object having excess unpolymerized resin retained on the surface thereof; (b) separating a portion of said excess unpolymerized resin from said object while leaving a thin film of unpolymerized resin on the surface thereof; (c) partially curing said thin film by exposing said thin film to a second light at a second peak wavelength; and then (d) further curing said intermediate object by heating, microwave irradiating, or both heating and microwave irradiating, to produce an object having a matte surface finish. ## Claims ### Claim 1 A method of making an object having a matte surface finish by stereolithography, comprising the steps of: (a) stereolithographically producing an intermediate object by polymerization of a dual cure resin with a first light having a first peak wavelength, the object having excess unpolymerized resin retained on the surface thereof; (b) separating a portion of said excess unpolymerized resin from said object while leaving a thin film of unpolymerized resin on the surface thereof; (c) partially curing said thin film by exposing said thin film to a second light at a second peak wavelength; and then (d) further curing said intermediate object by heating, microwave irradiating, or both heating and microwave irradiating, to produce an object having a matte surface finish. ### Claim 2 (depends on 1) The method of claim 1, wherein said second peak wavelength is shorter than said first peak wavelength. ### Claim 3 (depends on 1) The method of claim 1, wherein said first peak wavelength is at least 60 nanometers longer than said second peak wavelength. ### Claim 4 (depends on 1) The method of claim 1, wherein said first peak wavelength is between 360 and 400 nanometers. ### Claim 5 (depends on 1) The method of claim 1, wherein said first light has a full width at half maximum of not more than 40 nanometers. ### Claim 6 (depends on 1) The method of claim 1, wherein said second peak wavelength is between 100 nanometers and 250 nanometers. ### Claim 7 (depends on 1) The method of claim 1, wherein said second light has a full width at half maximum of not more than 40 nanometers. ### Claim 8 (depends on 1) The method of claim 1, wherein said separating step is carried out by spinning, blowing with a compressed gas, gravity draining, or a combination thereof. ### Claim 9 (depends on 1) The method of claim 1, wherein said object comprises a lattice. ### Claim 10 (depends on 1) The method of claim 1, wherein said object comprises a cushion. ### Claim 11 (depends on 1) The method of claim 1, wherein said object comprises a body contact surface. ### Claim 12 (depends on 1) The method of claim 1, wherein said object comprises a skin contact surface. ### Claim 13 (depends on 1) The method of claim 1, wherein said object is comprised of: (a) polyurethane, polyurea, or a copolymer thereof; (b) epoxy; (c) silicone; or (d) cyanate ester. ### Claim 14 (depends on 1) The method of claim 1, wherein said object is opaque. ### Claim 15 (depends on 1) The method of claim 1, wherein said resin comprises at least one pigment. ### Claim 16 (depends on 1) The method of claim 1, wherein said producing step is carried out by bottom-up or top-down stereolithography. ### Claim 17 (depends on 1) The method of claim 1, wherein said object of steps (b), (c) and (d) is unwashed. ### Claim 18 (depends on 1) The method of claim 1, wherein said retained portion of said resin is undiluted with solvent during said partially curing of step (c). ### Claim 19 (depends on 1) The method of claim 1, wherein said partially curing step (c) further comprises exposing said intermediate object to light at a third wavelength longer than said second wavelength, before exposing said object to light at said second wavelength, to partially decrease the matting of said finish, prior to said further curing step (d). ### Claim 20 (depends on 1) The method of claim 1, wherein said partially curing step (c) further comprises exposing said intermediate object to light at a fourth wavelength longer than said second wavelength, before and/or after exposing said object to light at said second wavelength, to stabilize said matte finish, prior to said further curing step (d).