# US 12,179,419 B2 · Process and apparatus for locally polymerizing a starting material by dual color photopolymerization and method for volumetric printing of a shaped body > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,179,419 B2 - Document ID: US12179419B2 - Status: Granted - Kind: B2 - Application number: 17/596,232 - Filed: 2020-06-08 - Published: 2022-09-29 - Granted: 2024-12-31 - Earliest claimed: 2019-06-06 - Assignees: xolo GmbH - Applicants: xolo GmbH - Inventors: Yves Garmshausen; Marcus Reuter; Marin Regehly; Dirk Radzinski - Web page: https://patentgrep.com/patent/US12179419B2 ## CPC - B29C 64/135: the energy source being concentrated, e.g. scanning lasers or focused light sources - B29C 64/264: Arrangements for irradiation - B29C 64/282: of the same type, e.g. using different energy levels - B33Y 10/00: Processes of additive manufacturing - B33Y 30/00: Apparatus for additive manufacturing; Details thereof or accessories therefor - B33Y 70/00: Materials specially adapted for additive manufacturing - C08F 2/50: with sensitising agents - C08F 122/1006: {of polyhydric alcohols or polyhydric phenols, e.g. ethylene glycol dimethacrylate} - C08F 220/04: Acids; Metal salts or ammonium salts thereof - C08F 220/56: Acrylamide; Methacrylamide - C08F 222/102: {of dialcohols, e.g. ethylene glycol di(meth)acrylate or 1,4-butanediol dimethacrylate} - C08F 222/104: {of tetraalcohols, e.g. pentaerythritol tetra(meth)acrylate} - C09B 11/26: Triarylmethane dyes in which at least one of the aromatic nuclei is heterocyclic {(phthaleins C09B11/24)} - C09B 11/28: Pyronines {; Xanthon, thioxanthon, selenoxanthan, telluroxanthon dyes} - C09B 57/00: Other synthetic dyes of known constitution - C09B 69/10: Polymeric dyes; Reaction products of dyes with monomers or with macromolecular compounds - G03F 7/0037: {Production of three-dimensional images} - G03F 7/029: Inorganic compounds; Onium compounds; Organic compounds having hetero atoms other than oxygen, nitrogen or sulfur - G03F 7/031: Organic compounds not covered by group G03F7/029 - G03F 7/2051: {Exposure without an original mask, e.g. using a programmed deflection of a point source, by scanning, by drawing with a light beam, using an addressed light or corpuscular source (G03F7/70 takes precedence)} - 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 - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS - C09B: ORGANIC DYES OR CLOSELY-RELATED COMPOUNDS FOR PRODUCING DYES {, e.g. PIGMENTS}; MORDANTS; LAKES (fermentation or enzyme using processes to synthesise a desired chemical compound C12P) - G03F: PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR; (phototypographic composing devices B41B; photosensitive materials or processes for photographic purposes G03C; electrophotography, sensitive layers or processes therefor G03G) ## Abstract The present invention relates to a process, an apparatus and photoswitchable photoinitiators for locally polymerizing a starting material by dual color photopolymerization and a method for volumetric printing of a shaped body (xolography). In particular, photoinitiators are provided, which cause raring of photopolymerizable formulations upon irradiation with two different wavelengths and which maybe used for volumetric printing (xolocure initiators). ## Claims ### Claim 1 A process for locally polymerizing a starting material by dual color photopolymerization, comprising: providing a polymerizable starting material containing photoinitiator molecules which can be converted by sequential optical excitation into a reactive state in which the photoinitiator molecules locally trigger polymerization of the starting material; and photopolymerizing the starting material in a local volume by irradiating light of a first wavelength and light of a second wavelength, different from the first wavelength, into the local volume, whereby in the local volume the photoinitiator molecules are converted, due to the absorption of the light of the first wavelength, from an initial state in which the photoinitiator molecules substantially do not absorb the light of the second wavelength, into an intermediate state with changed optical properties compared to the initial state, such that the photoinitiator molecules in the intermediate state absorb the light of the second wavelength; and the photoinitiator molecules are transferred from the intermediate state to the reactive state due to the absorption of the light of the second wavelength, which triggers the polymerization locally; (A) characterized in that the photoinitiator molecule is represented by the following formula (I)— wherein Ra and Rb are selected independently from unsubstituted or substituted aryl, unsubstituted or substituted alkyne or a linked to each other to form a unsubstituted or substituted ring structure, Y is selected from O, S, or N; where Y is N, the substituent contains the atoms necessary to complete a cyclic structure with R8 selected from the group consisting of benzimidazole, indoline, indole, dihydroquinoline, and tetrahydroquinoline; wherein Z is selected from N or CR4; wherein R3 to R8 are independently selected from the group consisting of H; D; halogen; NO2; CN; OH; SH; substituted or unsubstituted C1-C20-alkyl; substituted or unsubstituted C3-C20-cycloalkyl; substituted or unsubstituted C6-C48-aryl; substituted or unsubstituted C2-C42-heteroaryl; substituted or unsubstituted C2-C49-alkyl acyl; substituted or unsubstituted C2-C49-aryl acyl; substituted or unsubstituted C1-C20-alkoxy; substituted or unsubstituted C6-C48-aryloxy, and NH2; substituted or unsubstituted C1-C20-alkyl ester; substituted or unsubstituted C6-C48-aryl ester; substituted or unsubstituted C1-C20 alkyl amide; substituted or unsubstituted C6-C48-aryl amide; NR′2, SiR′3, —O—SiR′3 wherein R′ is independently selected from the group consisting of substituted or unsubstituted C1-C20-alkyl and substituted or unsubstituted C6-C48-aryl, two R′ may form a ring structure; substituted or unsubstituted carboxylic acids and salts thereof; substituted or unsubstituted sulfonic acids and salts thereof; substituted or unsubstituted sulfonic esters; substituted or unsubstituted sulfonic amides; formyl; ether, thioether; carbonate; carbonate ester; sulfates; boronic acids; boronic esters; phosphonic acids; phosphonic esters; phosphines; phosphates; peroxycarbonic acids; thiocarbonic acids; sulfinic acids; sulfinic esters; sulfonates; thiolesters, sulfoxides; sulfones; hydrazides; thioaldehydes; ketones; thioketones; oximes; hydrazines; nitroso; azo; diazo; diazonium; isocyanides; cyanate; isocyanate; thiocyanate; isothiocyanate; hydroperoxide; peroxide; acetals; ketal; orthoester; orthocarbonate esters; ammonium; imines; imides; azide; nitrate; isonitrile; nitrosoxy; substituted or unsubstituted carbamates; substituted or unsubstituted ethers; substituted or unsubstituted polyether carbamates; substituted or unsubstituted arylazo; substituted or unsubstituted C2-C20-alkynyl and substituted or unsubstituted C2-C20-alkenyl; wherein the one or more substituents, if present in one or more of R3-R8, are independently selected from the group consisting of D; halogen; NO2; CN, C2-C49-alkyl acyl; substituted or unsubstituted C1-C20-alkoxy; substituted or unsubstituted C6-C48-aryloxy; substituted or unsubstituted C2-C49-aryl acyl; (meth) acrylate; tosyl; NH2; and OH; and/or wherein two adjacent groups of R5-R8 may be linked to each other to form a fused ring structure; and wherein at least one of R3-R8, is selected from one of the following structures: wherein R14 to R25 are independently selected from the group consisting of H; D; halogen; NO2; CN; OH; SH; substituted or unsubstituted C1-C20-alkyl; substituted or unsubstituted C3-C20-cycloalkyl; substituted or unsubstituted C6-C48-aryl; substituted or unsubstituted C2-C42-heteroaryl; substituted or unsubstituted C2-C49-alkyl acyl; substituted or unsubstituted C2-C49-aryl acyl; substituted or unsubstituted C1-C20-alkoxy; substituted or unsubstituted C6-C48-aryloxy, and NH2; substituted or unsubstituted C1-C20-alkyl ester; substituted or unsubstituted C6-C48-aryl ester; substituted or unsubstituted C1-C20 alkyl amide; substituted or unsubstituted C6-C48-aryl amide; NR′2, SiR′3, —O—SiR′3 wherein R′ is independently selected from the group consisting of substituted or unsubstituted C1-C20-alkyl and substituted or unsubstituted C6-C48-aryl, two R′ may form a ring structure; substituted or unsubstituted carboxylic acids and salts thereof; substituted or unsubstituted sulfonic acids and salts thereof; substituted or unsubstituted sulfonic esters; substituted or unsubstituted sulfonic amides; formyl; ether, thioether; carbonate; carbonate ester; sulfates; boronic acids; boronic esters; phosphonic acids; phosphonic esters; phosphines; phosphates; peroxycarbonic acids; thiocarbonic acids; sulfinic acids; sulfinic esters; sulfonates; thiolesters, sulfoxides; sulfones; hydrazides; thioaldehydes; ketones; thioketones; oximes; hydrazines; nitroso; azo; diazo; diazonium; isocyanides; cyanate; isocyanate; thiocyanate; isothiocyanate; hydroperoxide; peroxide; acetals; ketal; orthoester; orthocarbonate esters; ammonium; imines; imides; azide; nitrate; isonitrile; nitrosoxy; substituted or unsubstituted carbamates; substituted or unsubstituted ethers; substituted or unsubstituted polyether carbamates; substituted or unsubstituted arylazo; substituted or unsubstituted C2-C20-alkynyl and substituted or unsubstituted C2-C20-alkenyl; wherein the one or more substituents, if present in one or more of R14-R25, are independently selected from the group consisting of D; halogen; NO2; CN, C2-C49-alkyl acyl; substituted or unsubstituted C1-C20-alkoxy; substituted or unsubstituted C6-C48-aryloxy; substituted or unsubstituted C2-C49-aryl acyl; (meth) acrylate; tosyl; NH2; and OH; and R15 and R16 may be linked to each other to form a unsubstituted or substituted ring structure; or (B) characterized in that the photoinitiator molecule is represented by the following formula (II) wherein X is selected from S, CR1R2, or NR1; Y is selected from O, S, or NRc; when Y is N, the substituent Rc contains the atoms necessary to complete a cyclic structure with R8 selected from the group consisting of benzimidazole, indoline, indole, dihydroquinoline, and tetrahydroquinoline; Z is selected from N or CR4; and R1 to R13 are independently selected as defined in R3 to R8 regarding formula (I) above. ### Claim 2 (depends on 1) A process according to claim 1, characterized in that the light of the first wavelength and the light of the second wavelength are simultaneously irradiated into the local volume. ### Claim 3 (depends on 1) A process according to claim 1, characterized in that the light of the second wavelength is irradiated into the local volume after the irradiation of the light of the first wavelength in the local volume has ended, the light of the second wavelength being irradiated before the end of a decay time of the intermediate state of the photoinitiator molecules. ### Claim 4 (depends on 1) A process according to claim 1, characterized in that the photoinitiator molecules in the intermediate state substantially do not absorb the light of the first wavelength. ### Claim 5 (depends on 1) A process according to claim 1, characterized in that the photoinitiator molecules are converted from the intermediate state to the initial state due to the absorption of light of a third wavelength in volumes where no polymerization is desired. ### Claim 6 (depends on 1) A process according to claim 1, characterized in that the photoinitiator molecules are converted into a reactive state due to the sequential absorption of light of the second wavelength which triggers a polymerization in the local volume. ### Claim 7 (depends on 1) A process according to claim 1, characterized in that the photoinitiator molecules are converted into a reactive state due to the absorption of the light of the second wavelength, which triggers a radical polymerization in the local volume. ### Claim 8 (depends on 1) A process according to claim 1, characterized in that R14, R15, and R16 are independently selected from H, D, CN, halogen, substituted or unsubstituted C1-C10-alkyl; substituted or unsubstituted C3-C10-cycloalkyl; substituted or unsubstituted C6-C32-aryl; or substituted or unsubstituted C2-C28-heteroaryl. ### Claim 9 (depends on 1) A process according to claim 1, characterized in that R19 is selected from substituted or unsubstituted C1-C10-alkyl; substituted or unsubstituted C3-C10-cycloalkyl; substituted or unsubstituted C6-C32-aryl; substituted or unsubstituted C2-C28-heteroaryl, substituted or unsubstituted C2-C20-alkynyl and substituted or unsubstituted C2-C20-alkenyl, the substituent may contain the atoms necessary to complete a cyclic structure with one of R5-R8 or R10-R13 forming an anthracene, thioxanthone or fluorenone. ### Claim 10 (depends on 1) A process according to one of claim 1, characterized in that R14 is NR′2, wherein R′ is independently selected from the group consisting of H, D, substituted or unsubstituted C1-C10-alkyl and substituted or unsubstituted C6-C32-aryl, and two R′ may form a ring structure; or OR′, wherein R′ is selected from the group consisting of H, D, substituted or unsubstituted C1-C10-alkyl; substituted or unsubstituted C3-C10-cycloalkyl; substituted or unsubstituted C6-C32-aryl; substituted or unsubstituted C2-C28-heteroaryl, SiR “3, wherein R” is independently selected from the group consisting of substituted or unsubstituted C1-C10-alkyl and substituted or unsubstituted C6-C32-aryl; and R15 and R16 are independently selected from H, D, CN, substituted or unsubstituted C1-C10-alkyl; substituted or unsubstituted C3-C10-cycloalkyl; substituted or unsubstituted C6-C32-aryl; substituted or unsubstituted C2-C28-heteroaryl. ### Claim 11 (depends on 1) A process according to claim 1, characterized in that R14 and R15 are OR′, wherein R′ is independently selected from the group consisting of H, D, substituted or unsubstituted C1-C10-alkyl; substituted or unsubstituted C3-C10-cycloalkyl; substituted or unsubstituted C6-C32-aryl; substituted or unsubstituted C2-C28-heteroaryl; and R16 is selected from H, D, CN, substituted or unsubstituted C1-C10-alkyl; substituted or unsubstituted C3-C10-cycloalkyl; substituted or unsubstituted C6-C32-aryl; substituted or unsubstituted C2-C28-heteroaryl. ### Claim 12 (depends on 1) A process according to claim 1, characterized in that R10-R13 are independently selected from the group consisting of H and electron withdrawing groups (EWG), and one of R5-R8 is selected from unsubstituted or substituted arylacyl; or unsubstituted or substituted alkylacyl; and/or at least one of R5-R8 is independently selected from the group consisting of electron donating groups (EDG), and at least one of R5-R8, R10-R13 is selected from unsubstituted or substituted arylacyl; or unsubstituted or substituted alkylacyl; or at least one of R6, R7 and R12 is selected from the group consisting of CF3, SO2Me, SO2NH2, CN, F, NO2, C6-aryl, unsubstituted C6-arylacyl of the following formula dimethoxy-substituted arylacyl of the formula methoxy-substituted arylacyl of the formula fluorine-substituted arylacyl of the following formula alternatively of the formula and C6-aryl. ### Claim 13 (depends on 1) A process according to claim 1, characterized in that the photoinitiator molecules comprise one or more of the following compounds: ### Claim 14 (depends on 1) A process according to claim 1, characterized in that the polymerizable starting material further contains a co-initiator and/or a sensitizer. ### Claim 15 (depends on 1) A process according to claim 1, characterized in that the polymerizable starting material further contains an additive, an acid and/or a base. ### Claim 16 A process for locally polymerizing a starting material by dual color photopolymerization, comprising: providing a polymerizable starting material containing photoinitiator molecules which can be converted by sequential optical excitation into a reactive state in which the photoinitiator molecules locally trigger polymerization of the starting material; and photopolymerizing the starting material in a local volume by irradiating light of a first wavelength and light of a second wavelength, different from the first wavelength, into the local volume, whereby in the local volume the photoinitiator molecules are converted, due to the absorption of the light of the first wavelength, from an initial state in which the photoinitiator molecules substantially do not absorb the light of the second wavelength, into an intermediate state with changed optical properties compared to the initial state, such that the photoinitiator molecules in the intermediate state absorb the light of the second wavelength; and the photoinitiator molecules are transferred from the intermediate state to the reactive state due to the absorption of the light of the second wavelength, which triggers the polymerization locally; characterized in that a light beam of light of the first wavelength and a light beam of light of the second wavelength are irradiated at least partially overlapping in the local volume. ### Claim 17 (depends on 1) A process according to claim 1, characterized in that the starting material is polymerized in several local volumes by means of photopolymerization and thus a three-dimensional shaped body is produced in the starting material. ### Claim 18 (depends on 1) A process for 3D-printing a shaped body, wherein the shaped body is produced by means of a process according to claim 1. ### Claim 19 Apparatus for locally polymerizing a starting material by dual color photopolymerization, comprising: an intake for a polymerizable starting material; light generating means arranged to generate light of a first wavelength and light of a second wavelength, the second wavelength being different from the first wavelength; and a light guide device arranged to irradiate the light of the first wavelength and the light of the second wavelength into a local volume; said device being adapted to perform the following procedure: taking up the polymerizable starting material by said intake, said starting material containing photoinitiator molecules which can be excited by sequential optical excitation into a reactive state in which the photoinitiator molecules locally initiate polymerization of the starting material; and photopolymerizing the starting material in a local volume by irradiating the light of the first wavelength and the light of the second wavelength into the local volume, whereby in the local volume the photoinitiator molecules, due to the absorption of the light of the first wavelength, are converted from an initial state in which the photoinitiator molecules substantially do not absorb the light of the second wavelength into an intermediate state with changed optical properties compared to the initial state, such that the photoinitiator molecules in the intermediate state absorb the light of the second wavelength; and the photoinitiator molecules are transferred from the intermediate state to the reactive state due to the absorption of the light of the second wavelength, which triggers the polymerization locally.