High speed charge programmed printing of conductor / dielectric 3D structures

Abstract

A method is provided which includes (a) providing a mixture comprising a first type of resin and a second type of resin in a vat, wherein (i) the first type of resin photopolymerizes on exposure to a first wavelength of light, (ii) the second type of resin photopolymerizes on exposure to a second wavelength of light, (iii) the first type of resin is different than the second type of resin, and (iv) the first wavelength of light is different than the second wavelength of light, and (b) exposing the mixture to a plurality of patterns of light in succession, wherein at least a first pattern of light is projected at the first wavelength and at least a second pattern is projected at the second wavelength. In embodiments, the method uses one wavelength of light at varying intensities. In embodiments, the method is used to fabricate three-dimensional multi-material objects.

Description

Attorney Docket # 00495-0026 (B2025-20)HIGH SPEED CHARGE PROGRAMMED PRINTING OF CONDUCTOR / DIELECTRIC 3D STRUCTURESREFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 683,199, filed August 14, 2024, the contents of which is hereby incorporated by reference.FIELD

[0002] The present invention generally relates to stereolithographic techniques for the fabrication of three-dimensional multi -material structures.BACKGROUND

[0003] Electronics with defined three-dimensional (3D) metal-dielectric patterns are used in many different types of applications, such as antennas, actuators, sensors, integrated circuits, metamaterials, and energy storage devices, to name a few examples. However, conventional methods of creating circuits (typically composed of a combination of conductors and dielectric materials) in multiple dimensions (e.g., lithography, etching, or deposition), are usually limited to relatively simple layouts, often with structural materials needed solely to support the layouts, adding to the expense of producing such circuits and increasing their physical size and weight.

[0004] Attempts to improve fabrication of metal-dielectric materials have been made using various 3D printing methods, such as with a toolpath (e.g., using nozzle or laser rastering, to give a few examples), as well as with stereolithography (e.g., by relying on different resins cycled in and out of a vat to selectively build up a circuit). However, these have not provided a satisfactory solution, having a long printing time and being complex and difficult to administer, limiting the ability' to make arbitrary' circuits.

[0005] What is needed is a way to quickly and accurately fabricate conductor / dielectric 3D structures.SUMMARY

[0006] In view of the above, it is an object of the present invention to provide a technological solution to address the long felt need and technological challenges faced in 3D printing circuits by providing systems, methods and program products for dual -wav elength printing which facilitates the rapid fabrication of multi-material components within a single vat of a 3D printer, as well as a product produced by said systems, methods and program products. Further, method, systems, and program products are disclosed for multi-material additive manufacturing within a single vat using a single-wavelength light source as well as a product14854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) produced by said system, method and program product. By spatially controlling material composition through differential photopolymerization reactivity of monomers, embodiments enable the programmable distribution of functional properties within the printed structure.

[0007] In exemplary' embodiments, a method for 3D printing a multi -material object includes the steps of: (a) providing a mixture including a first ty pe of resin and a second ty pe of resin in a vat. wherein: (i) the first type of resin photopolymerizes on exposure to a first wavelength of light; (ii) the second type of resin photopolymerizes on exposure to a second wavelength of light; (iii) the first type of resin is different than the second type of resin; and (iv) the first wavelength of light is a different w avelength than the second w avelength of light; and (b) exposing the mixture to a plurality of patterns of light in succession, wherein at least a first pattern of light is projected at the first wavelength and at least a second pattern is projected at the second w avelength, wherein the multi -material object is formed as a result.

[0008] In exemplary' embodiments, a method for 3D printing a multi -material object includes the steps of: (a) providing a mixture including a first type of resin, a second type of resin, a catalyst, and a first material in a vat, wherein: (i) the first type of resin photopolymerizes on exposure to a first wavelength of light; (ii) the second type of resin photopolymerizes on exposure to a second wavelength of light; (iii) the first wavelength of light is a different wavelength than the second wavelength of light; and (iv) the catalyst promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized; (b) exposing the mixture to a plurality of patterns of light in succession, wherein each pattern of light is projected at a wavelength selected from the first wavelength or the second wavelength, wherein the multi -material object is formed as a result.

[0009] In exemplary embodiments, a method for 3D printing a multi -material object includes the steps of: (a) forming a mixture by combining: (i) a first type of resin which photopolymerizes on exposure to a first wavelength of light; and (ii) a second ty pe of resin which photopolymerizes on exposure to a second wavelength of light, w herein the first type of resin is different than the second type of resin and the first wavelength of light is a different wavelength than the second w avelength of light; (b) exposing the mixture in a vat to a first pattern of light at the first wavelength; and (c) exposing the mixture in the vat to a second pattern of light at the second wavelength, wherein the multi-material object is formed as a result. In embodiments, step (b) is performed before step (c). In embodiments, step (b) is performed after step (c). In embodiments, step (b) is performed before and after step (c). In embodiments, step (c) is performed before and after step (b).24854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20)

[0010] In exemplary embodiments, a method for 3D printing a multi -material object includes the steps of: (a) forming a mixture by combining: (i) a first type of resin which photopolymerizes on exposure to a first wavelength of light; (ii) a second type of resin which photopolymerizes on exposure to a second wavelength of light; (iii) a first material; (iv) and a catalyst which promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized; wherein the first type of resin is different than the second type of resin and the first wavelength of light is a different wavelength than the second wavelength of light; (b) exposing the mixture in a vat to a first pattern of light at the first wavelength; and (c) exposing the mixture in the vat to a second pattern of light at the second wavelength, wherein the multi-material object is formed as a result. In embodiments, step (b) is performed before step (c). In embodiments, step (b) is performed after step (c). In embodiments, step (b) is performed before and after step (c). In embodiments, step (c) is performed before and after step (b).

[0011] In embodiments, the first wavelength is 405 nm and the second wavelength is 365 nm.

[0012] In embodiments, the first type of resin and the second type of resin are homogeneously mixed in the vat.

[0013] In embodiments, the first type of resin has a neutral charge and the second type of resin has a positive or negative charge.

[0014] In embodiments, the first type of resin is a neutral acrylate monomer and the second type of resin is a charged epoxy monomer.

[0015] In embodiments, the first type of resin photopolymerizes by ring opening polymerization.

[0016] In embodiments, the second type of resin photopolymerizes photopolymerize by free radical polymerization.

[0017] In embodiments, the method further includes providing a metal and a catalyst which promotes deposition of the metal on the photopolymerized second type of resin.

[0018] In embodiments, the multi-material object includes a three-dimensional circuit. In embodiments, the multi-material object includes a programmed charged mosaic.

[0019] In embodiments, the first material is a metal. In embodiments, the metal is Nickel. In embodiments, the metal is Copper. In embodiments, the metal is Iron Oxide.

[0020] In exemplary embodiments, a three-dimensional multi -material object is created by a process which includes: (a) providing a mixture including a first type of resin and a second34854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) type of resin in a vat, wherein: (i) the first type of resin photopolymerizes on exposure to a first wavelength of light; (ii) the second type of resin photopolymerizes on exposure to a second wavelength of light; (iii) the first type of resin is different than the second type of resin; and (iv) the first wavelength of light is a different wavelength than the second wavelength of light; and (b) exposing the mixture to a plurality' of patterns of light in succession, wherein at least a first pattern of light is projected at the first wavelength and at least a second pattern is projected at the second wavelength, wherein the three-dimensional multi-material object is formed as a result.

[0021] In exemplary' embodiments, a three-dimensional multi -material object is created by a process which includes: (a) providing a mixture including a first type of resin, a second type of resin, a catalyst, and a first material in a vat, wherein: (i) the first type of resin photopolymerizes on exposure to a first wavelength of light; (ii) the second type of resin photopolymerizes on exposure to a second wavelength of light; (iii) the first wavelength of light is a different wavelength than the second wavelength of light; and (iv) the catalyst promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized; (b) exposing the mixture to a plurality of patterns of light in succession, wherein each pattern of light is projected at a wavelength selected from the first wavelength or the second wavelength, wherein the three-dimensional multi-material object is formed as a result.

[0022] In exemplary embodiments, a three-dimensional multi -material object is created by a process which includes: (a) forming a mixture by combining: (i) a first type of resin which photopolymerizes on exposure to a first wavelength of light; and (ii) a second type of resin which photopolymerizes on exposure to a second wavelength of light, wherein the first type of resin is different than the second type of resin and the first wavelength of light is a different wavelength than the second wavelength of light; (b) exposing the mixture in a vat to a first pattern of light at the first w avelength; and (c) exposing the mixture in the vat to a second pattern of light at the second w avelength, wherein the three-dimensional multi -material object is formed as a result. In embodiments, step (b) is performed before step (c). In embodiments, step (b) is performed after step (c). In embodiments, step (b) is performed before and after step (c). In embodiments, step (c) is performed before and after step (b).

[0023] In exemplary embodiments, a three-dimensional multi-material object is created by a process which includes: (a) forming a mixture by combining: (i) a first type of resin which photopolymerizes on exposure to a first w avelength of light; (ii) a second type of resin which44854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) photopolymerizes on exposure to a second wavelength of light; (iii) a first material; (iv) and a catalyst which promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized; wherein the first type of resin is different than the second type of resin and the first wavelength of light is a different wavelength than the second wavelength of light; (b) exposing the mixture in a vat to a first pattern of light at the first wavelength; and (c) exposing the mixture in a vat to a second pattern of light at the second wavelength. In embodiments, step (b) is performed before step (c). In embodiments, step (b) is performed after step (c). In embodiments, step (b) is performed before and after step (c). In embodiments, step (c) is performed before and after step (b).

[0024] In embodiments, the three-dimensional multi-material object includes an electronic circuit. In embodiments, the three-dimensional multi-material object includes a programmed charged mosaic. In embodiments, the three-dimensional multi -material object includes an antenna.

[0025] In embodiments, the mixture is formed in the vat.

[0026] In embodiments, the first wavelength is 405 nm and the second wavelength is 365 nm.

[0027] In embodiments, the first type of resin and the second type of resin are homogeneously mixed in the vat.

[0028] In embodiments, the first type of resin has a neutral charge and the second type of resin has a positive or negative charge. In embodiments, the first type of resin is a neutral acrylate monomer and the second type of resin is a charged epoxy monomer.

[0029] In embodiments, the first type of resin is configured to photopolymerize by ring opening polymerization.

[0030] In embodiments, the second ty pe of resin is configured to photopolymerize by free radical polymerization.

[0031] In embodiments, the method further includes providing a metal and a catalyst which promotes deposition of the metal on the photopolymerized second type of resin.

[0032] In embodiments, the first material is a metal. In embodiments, the metal is Nickel. In embodiments, the metal is Copper. In embodiments, the metal is Iron Oxide.

[0033] In exemplary embodiments, a method for 3D printing a multi-material object includes the steps of: (a) providing a mixture including a first type of resin and a second type of resin in a vat, wherein: (i) the first type of resin photopolymerizes at a first polymerization rate on exposure to a first wavelength of light at a first exposure energy; (ii) the second type of54854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) resin photopolymerizes at a second polymerization rate on exposure to the first wavelength of light at a second exposure energy; (iii) the first type of resin is different than the second type of resin; and (iv) the first polymerization rate is higher than the second polymerization rate; and (b) exposing the mixture to a plurality of patterns of light in succession, wherein at least a first pattern of light is projected at a first intensity by a light source for a first period of time and at least a second pattern is projected by the light source at a second intensity for a second period of time, wherein the multi-material object is formed as a result.

[0034] In exemplar}7embodiments, a method for 3D printing a multi-material object includes the steps of: (a) providing a mixture including a first ty pe of resin, a second type of resin, a catalyst, and a first material in a vat, wherein: (i) the first type of resin photopolymerizes at a first polymerization rate on exposure to a first wavelength of light at a first exposure energy; (ii) the second type of resin photopolymerizes at a second polymerization rate on exposure to the first wavelength of light at a second exposure energy'; (iii) the first type of resin is different than the second type of resin; and (iv) the first polymerization rate is higher than the second polymerization rate; and (v) the catalyst promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized; and (b) exposing the mixture to a plurality of patterns of light in succession, wherein at least a first pattern of light is projected at a first intensity by a light source for a first period of time and at least a second pattern is projected at a second intensity by a light source for a second period of time, wherein the multi-material object is formed as a result.

[0035] In exemplary' embodiments, a method for 3D printing a multi -material object includes the steps of: (a) forming a mixture by combining: (i) a first type of resin which photopolymerizes at a first polymerization rate on exposure to a first wavelength of light; and (ii) a second type of resin which photopolymerizes at a second polymerization rate on exposure to the first wavelength of light, wherein the first type of resin is different than the second type of resin and the first polymerization rate is higher than the second polymerization rate; (b) exposing the mixture in a vat to a first pattern of light projected by a light source at the first wavelength at a first intensity for a first period of time; and (c) exposing the mixture in the vat to a second pattern of light projected by the light source at the first wavelength at a second intensity for a second period of time, wherein the multi -material object is formed as a result. In embodiments, step (b) is performed before step (c). In embodiments, step (b) is performed after step (c). In embodiments, step (b) is performed before and after step (c). In embodiments, wherein step (c) is performed before and after step (b).64854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20)

[0036] In exemplary embodiments, a method for 3D printing a multi -material object includes the steps of: (a) forming a mixture by combining: (i) a first type of resin which photopolymerizes at a first polymerization rate on exposure to a first wavelength of light at a first exposure energy; (ii) a second type of resin which photopolymerizes at a second polymerization rate on exposure to the first wavelength of light at a second exposure energy; (iii) a first material; (iv) and a catalyst which promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized; wherein the first type of resin is different than the second type of resin and the first polymerization rate is higher than the second polymerization rate; (b) exposing the mixture in a vat to a first pattern of light projected by a light source at the first wavelength at a first intensity for a first period of time; and (c) exposing the mixture in the vat to a second pattern of light projected by the light source operating on a second duty cycle at the first wavelength at a second intensity for a second period of time, wherein the multi -material object is formed as a result. In embodiments, step (b) is performed before step (c). In embodiments, step (b) is performed after step (c). In embodiments, step (b) is performed before and after step (c). In embodiments, wherein step (c) is performed before and after step (b).

[0037] In embodiments, the first wavelength is between 395 and 415 nm.

[0038] In embodiments, the first type of resin and the second type of resin are homogeneously mixed in the vat.

[0039] In embodiments, the first type of resin has a neutral charge and the second ty pe of resin has a positive or negative charge.

[0040] In embodiments, the first type of resin is a neutral acrylate monomer and the second type of resin is a charged methacrylate monomer.

[0041] In embodiments, the first type of resin photopolymerizes by free radical polymerization. In embodiments, the second type of resin photopolymerizes by free radical polymerization.

[0042] In embodiments, the method further includes providing a metal and a catalyst which promotes deposition of the metal on the photopolymerized second type of resin.

[0043] In embodiments, the method further includes providing a metal ion solution and placing the multi-material object in the metal ion solution, such that metal is deposited onto portions of the multi -material object fabricated upon exposure to light at the first wavelength at the second intensity.74854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20)

[0044] In embodiments, the metal is Nickel. In embodiments, the metal is Copper. In embodiments, the metal is Iron Oxide.

[0045] In embodiments, the multi -material object includes a three-dimensional circuit. In embodiments, the multi-material object includes a programmed charged mosaic.

[0046] In embodiments, the first material is a metal. In embodiments, the metal is Nickel. In embodiments, the metal is Copper. In embodiments, the metal is Iron Oxide.

[0047] In embodiments, the first intensity is the same as the second intensity. In embodiments, the first intensity is different than the second intensity. In embodiments, the first period of time is the same as the second period of time. In embodiments, the first period of time is different than the second period of time.

[0048] In exemplary embodiments, a three-dimensional multi -material object is created by the process including: (a) providing a mixture including a first type of resin and a second type of resin in a vat, wherein: (i) the first type of resin photopolymerizes at a first polymerization rate on exposure to a first wavelength of light at a first exposure energy; (ii) the second type of resin photopolymerizes at a second polymerization rate on exposure to the first wavelength of light at a second exposure energy; (iii) the first type of resin is different than the second type of resin; and (iv) the first polymerization rate is higher than the second polymerization rate; and (b) exposing the mixture to a plurality of patterns of light in succession, wherein at least a first pattern of light is projected at a first intensity by a light source for a first period of time and at least a second pattern is projected at a second intensity by the light source for a second period of time, wherein the three-dimensional multi-material object is formed as a result.

[0049] In exemplary embodiments, a three-dimensional multi -material object is created by the process including: (a) providing a mixture including a first type of resin, a second type of resin, a catalyst, and a first material in a vat, wherein: (i) the first type of resin photopolymerizes at a first polymerization rate on exposure to a first wavelength of light at a first exposure energy; (ii) the second type of resin photopolymerizes at a second polymerization rate on exposure to the first wavelength of light at a second exposure energy; (iii) the first type of resin is different than the second type of resin; and (iv) the first polymerization rate is higher than the second polymerization rate; and (v) the catalyst promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized; and (b) exposing the mixture to a plurality of patterns of light in succession, wherein at least a first pattern of light is projected at a first intensity by a light source for a first period of time and at84854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) least a second pattern is projected at a second intensity by a light source for a second period of time, wherein the three-dimensional multi -material object is formed as a result.

[0050] In exemplary embodiments, a three-dimensional multi -material object is created by the process including: (a) forming a mixture by combining: (i) a first ty pe of resin which photopolymerizes at a first polymerization rate on exposure to a first wavelength of light; and(ii) a second type of resin which photopolymerizes at a second polymerization rate on exposure to the first wavelength of light, wherein the first type of resin is different than the second type of resin and the first polymerization rate is higher than the second polymerization rate; (b) exposing the mixture in a vat to a first pattern of light projected by a light source at the first wavelength at a first intensity for a first period of time; and (c) exposing the mixture in the vat to a second pattern of light projected by the light source at the first wavelength at a second intensity for a second period of time, wherein the three-dimensional multi -material object is formed as a result. In embodiments, step (b) is performed before step (c). In embodiments, step (b) is performed after step (c). In embodiments, step (b) is performed before and after step (c). In embodiments, step (c) is performed before and after step (b).

[0051] In exemplary embodiments, a three-dimensional multi-material object is created by the process including: (a) forming a mixture by combining: (i) a first ty pe of resin which photopolymerizes at a first polymerization rate on exposure to a first wavelength of light at a first exposure energy; (ii) a second type of resin which photopolymerizes at a second polymerization rate on exposure to the first wavelength of light at a second exposure energy;(iii) a first material; (iv) and a catalyst which promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized; wherein the first type of resin is different than the second type of resin and the first polymerization rate is higher than the second polymerization rate; (b) exposing the mixture in a vat to a first pattern of light projected by a light source at the first wavelength at a first intensity for a first period of time; and (c) exposing the mixture in the vat to a second pattern of light projected by the light source operating at the first wavelength at a second intensity for a second period of time, wherein the three-dimensional multi-material object is formed as a result. In embodiments, step (b) is performed before step (c). In embodiments, step (b) is performed after step (c). In embodiments, step (b) is performed before and after step (c). In embodiments, step (c) is performed before and after step (b).

[0052] In embodiments, the three-dimensional multi-material object includes an electronic circuit.94854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20)

[0053] In embodiments, the three-dimensional multi -material object includes a programmed charged mosaic.

[0054] In embodiments, the three-dimensional multi -material object includes an antenna.

[0055] In embodiments, the mixture is formed in the vat.

[0056] In embodiments, the first wavelength is 395 and 415 nm.

[0057] In embodiments, the first type of resin and the second type of resin are homogeneously mixed in the vat.

[0058] embodiments, the first type of resin has a neutral charge and the second type of resin has a positive or negative charge.

[0059] In embodiments, the first type of resin is a neutral acrylate monomer and the second type of resin is a charged methacrylate monomer.

[0060] In embodiments, the first type of resin is configured to photopolymerize by free radical polymerization. In embodiments, the second type of resin is configured to photopolymerize by free radical polymerization.

[0061] In embodiments, the method further includes providing a metal and a catalyst which promotes deposition of the metal on the photopolymerized second type of resin.

[0062] In embodiments, the three-dimensional multi-material object includes metal deposited on the surface of the multi -material object along portions fabricated upon exposure to light at the first wavelength at the second intensity. In embodiments, the metal is Nickel. In embodiments, the metal is Copper. In embodiments, the metal is Iron Oxide.

[0063] In embodiments, the first material is a metal. In embodiments, the metal is Nickel. In embodiments, the metal is Copper. In embodiments, the metal is Iron Oxide.

[0064] In exemplary embodiments, a method includes: (a) obtaining, by a computing device, a design file corresponding to a digital representation of a three-dimensional multimaterial object; and (b) generating, by the computing device, a print file based upon the design file, wherein the print file contains machine-readable instructions which, when executed by a three-dimensional printer, cause a light source of the three-dimensional printer to: (i) project at least a first pattern of light at a first intensity at a first wavelength for a first period of time; and (ii) project at least a second pattern of light at a second intensity at the first wavelength for a second period of time, wherein the first period of time is less than the second period of time, thereby fabricating at least a portion of the three-dimensional multi -material object.

[0065] In exemplary embodiments, a method includes: (a) obtaining, by a computing device, a design file corresponding to a digital representation of a three-dimensional multi-104854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) material object; and (b) generating, by the computing device, a print file based upon the design file, wherein the print file contains machine-readable instructions which, when executed by a three-dimensional printer, cause a light source of the three-dimensional printer to project a plurality of patterns of light in succession, wherein at least a first pattern of light is projected at a first intensity at a first wavelength for a first period of time, wherein at least a second pattern of light is projected at a second intensity at the first wavelength for a second period of time, and wherein the first period of time is less than the second period of time, thereby fabricating at least a portion of the three-dimensional multi -material object.

[0066] In exemplary embodiments, a computing device includes: (a) one or more processors; and (b) a non-transitory computer readable storage medium, wherein the non- transitory computer readable storage medium contains computer readable instructions that, when executed by the one or more processors, cause the one or more processors to generate a print file based upon a design file corresponding to a digital representation of a three- dimensional multi-material object, wherein the print file contains instructions which, when executed by a three-dimensional printer, cause a light source of the three-dimensional printer to: (i) project at least a first pattern of light at a first intensity at a first wavelength while the first light source for a first period of time; and (ii) project at least a second pattern of light at the first wavelength at a second intensity while the first light source for a second period of time, wherein the first period of time is less than the second period of time, thereby fabricating at least a portion of the three-dimensional multi-material object.

[0067] In exemplary embodiments, a computing device includes: (a) one or more processors; and (b) a non-transitory computer readable storage medium, wherein the non- transitory computer readable storage medium contains computer readable instructions that, when executed by the one or more processors, cause the one or more processors to generate a print file based upon a design file corresponding to a digital representation of a three- dimensional multi-material object, wherein the print file contains instructions which, when executed by a three-dimensional printer, cause a light source of the three-dimensional printer to project a plurality of patterns of light in succession, wherein at least a first pattern of light is projected at a first intensity at a first wavelength for a first period of time, wherein at least a second pattern of light is proj ected at a second intensity at the first wavelength for a second period of time, and wherein the first period of time is less than the second period of time, thereby fabricating at least a portion of the three-dimensional multi -material object

[0068] Other features and advantages of the present invention will become readily apparent114854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) from the following detailed description and the accompanying drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0069] The above and related objects, features and advantages of the present invention will be more fully understood by reference to the following, detailed description of the preferred, albeit illustrative, embodiment of the present invention when taken in conjunction with the accompanying figures, wherein:

[0070] FIG. 1 A is a schematic of a conventional stereolithographic printer existing in the prior art;

[0071] FIG. 1 B is a photograph of a 3D printed obj ect continuing a single material using a conventional stereolithographic printer;

[0072] FIG. 2A is a schematic of a stereolithographic printer used for making certain multimaterial objects;

[0073] FIGs. 2B-2D provides photographs of multi -material objects;

[0074] FIG. 3 illustrates a stereolithographic printer used for 3D printing in accordance with exemplary' embodiments of the present invention;

[0075] FIG. 4A is a diagram showing photopolymerization of a first type of resin and a second type of resin occurring at different wavelengths in accordance with exemplary embodiments of the present invention;

[0076] FIG. 4B provides CAD models, and corresponding photographs, of 3D printed structures in accordance with exemplary embodiments of the present invention;

[0077] FIGs. 5A-5C are diagrams of an example of electroless deposition in accordance with exemplary' embodiments of the present invention;

[0078] FIGs. 6-7 are flow charts showing steps for 3D printing a multi-material object in accordance with exemplary embodiments of the present invention;

[0079] FIG. 8 is a diagram illustrating the use of a 3D printer to 3D printing a multimaterial object involving a single light source projecting a single wavelength of light in accordance with exemplary' of the present invention;

[0080] FIG. 9 is a diagram illustrating the manufacturing process of three-dimensional multi -material objects 3D printed in accordance with exemplary embodiments of the present invention; and

[0081] FIGs. 10 and 11 are flow charts showing steps for reactivity -controlled multi-124854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) material 3D printing in accordance with exemplary7embodiments of the present invention.DETAILED DESCRIPTION

[0082] The present invention generally relates to stereolithographic techniques for the fabrication of three-dimensional multi-material structures.

[0083] Conventional stereography has normally been used to fabricating three-dimensional structures using one material.

[0084] FIG. 1A is a schematic of a conventional stereolithographic printer existing in the prior art. As shown in FIG. 1A, a stereolithographic printer (e.g., printer 100) typically uses light (e g., UV light 102. which may be emitted from a light source, such as light source 116) to cure resin (e.g., polymer resin 112) in a vat (e.g., vat 106) to form a 3D printed structure / object (e.g., 3D printed object 1 10). Depending on the printer, the light may be reflected off of one or mirrors (e.g., mirror 114) and through one or more focusing lens (e.g., focusing lens 104). The resin may be cured or photopolymerized by the light on a platform (e.g., printing platform 118), which is typically capable of being lifted in and out of the vat of resin by an elevator (e.g., elevator 108). FIG. IB is a photograph of a 3D printed object containing a single material using a conventional stereolithographic printer.

[0085] In the past, the inventors wrote about techniques for creating multi-material structures (e.g., Hensleigh. R.. Cui, H., Xu, Z. et al., "‘Charge-programmed three-dimensional printing for multi-material electronic devices”, which is hereby incorporated by reference as if fully set forth herein, and Nat Electron 3, 216-224 (2020) and Wang, Z., et al., '‘Charge- Programmable Photopolymers for 3D Electronics via Additive Manufacturing.” Advanced Functional Materials, vol. 34, 2024, p. 2313839, which is hereby incorporated by reference as if fully set forth herein).

[0086] FIG. 2A is a schematic of a stereolithographic printer used for making certain multimaterial objects. FIGs. 2B-2D provides photographs of multi-material objects.

[0087] As shown in FIG. 2A. such a stereolithographic printer (e.g., stereolithographic printer 200) shares certain aspects in common with conventional printers, including the use of a light source (E.g., LED 216 and modulator 226 used to modulate the light), to generate light (e.g., projected image 202), and projecting the light onto a vat (e.g., vat 206) using various optics (e.g., focusing lens 204 and mirror 214) in order to generate a 3D printed object or structure (e.g., 3D printed object 210), normally on a printing platform (e.g.. platform 218) which can be elevated out of the vat by an elevator (e.g., elevator 208). The stereolithographic printer depicted in FIG. 2A further includes, however, two inputs, a neutral monomer input134854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20)220, and a negative monomer input 222, respectively containing a first type of resin (e.g., resin 212a) with a neutral monomer and a second type of resin with a charged monomer having a negative charge (e.g., resin 212b), as well as a recycling channel (e.g., channel 224) designed to allow the resin to be flushed from the vat. In embodiments, the stereolithographic printer includes a positive monomer input, for example, instead of a negative monomer input 222, and the charge of the charged monomer is positive.

[0088] In embodiments, this printer relies upon electroless deposition. Electroless deposition is a chemical process that deposits a metal coating onto a substrate without the use of electrical current, relying on a catalyst to initiate the reaction. Through precise control of the charge, charged catalyst ions are selectively absorbed onto the 3D patterned polymers, facilitating the selective electroless deposition of metal on 3D printed objects.

[0089] For example, as shown in FIG. 2B, various multi-material objects (e.g., structures 230, 240, 250) having interwoven dielectric components (e.g., components 232, 242, 252) and nickel-phosphorus alloy components (e g., components 234, 244, 254) were able to printed. Similarly, as shown in FIG. 2C, a multi-material object (e.g.. structure 260) can be printed composed of an iron oxide component (e g., component 262) and a copper component (e.g., component 264). Additionally, as shown in FIG. 2D, electronics (in FIG. 2D, of several centimeters in size) can be created of multi-materials, including various antennas, such as a 3D folded electrical small antenna 270 (comprising low loss resin components 272 and copper components 274), a tough transmit array 280 (comprising polyimide components 282 and copper antennas 284), and a stretchable patch antenna 290 (including elastomer 292 and liquid metal EGain 294).

[0090] While this process is compatible with variety of materials such as Nickel (Ni), Copper (Cu), and Iron Oxide (Fe3O4), the stereolithographic printer in FIG. 2A is conventionally costly and cumbersome to operate, requiring material change process, such as frequent flushing of resin through the recycling channel 224 and cleaning of the object 210. The present invention provides a method which improves both the printing, as well as quality’, of 3D printed multi-material structures, and allows for the creation of dielectric-metal 3D structures.

[0091] FIG. 3 illustrates a stereolithographic printer used for 3D printing in accordance with exemplary embodiments of the present invention. In embodiments of the present invention, the stereolithographic printer (e.g.. stereolithographic printer 300) includes components similar to the stereolithographic printer 100 and 200. In embodiments, the144854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) stereolithographic printer (e.g., printer 300) includes one or more light sources and / or optics (e.g., light source 316), which may include, for example, LEDs. UV light generators, focusing lenses, and minors, configured to project one or more light images, as shown by light projection 302. In embodiments, the light source is configured to generate multiple wavelengths of light (e.g., infrared, visible, and ultraviolet light, to give a few' examples). In embodiments, the wavelengths may be selected from a band (e.g., between 395 and 415 nm, to give an example). In embodiments the stereolithographic printer includes a vat (e.g., vat 306).

[0092] In embodiments, the vat is used to store a mixture (e.g., mixture 312). In embodiments, the mixture may be homogenously mixed. In embodiments, the mixture is created by combining components of the mixture in the vat. In embodiments, the mixture is created by combining components of the mixture outside of the vat. In embodiments, the mixture includes a plurality of types of resins, (e.g., a first type of resin 312a, and a second type of resin 312b).

[0093] In embodiments, at least one of the types of resin is a monomer. In embodiments, the first type of resin comprises an acrylate monomer (e.g.. Trimethylolpropane triacrylate, “TMPTA”). In embodiments, the second type of resin comprises an epoxy monomer.

[0094] In embodiments, the first type of resin has a neutral charge. In embodiments, the second type of resin has a charge (e.g., a positive or negative charge). In embodiments, the first type of resin photopolymerizes by ring opening polymerization. In embodiments, the first type of resin photopolymerizes by radical polymerization. In embodiments, the second type of resin photopolymerizes by free radical polymerization. In embodiments, the second type of resin can photopolymerizes by epoxy polymerization. In embodiments, the photopolymerization of the plurality of resin creates a multi -material 3D structure (e.g.. 3D structure 310a). In embodiments, the photopolymerization of the second type of resin creates a negative photopolymer. In embodiments, the negative photopolymer provides a surface for the deposition of one or more materials (e.g., a metal such as copper).

[0095] FIG. 4A is a diagram showing photopolymerization of a first type of resin and a second type of resin occurring at different wavelengths in accordance with exemplary embodiments of the present invention. In embodiments, each type of resin of the plurality of types of resin photopolymerizes at a respective wavelength. In embodiments, each respective wavelength is different. For example, in embodiments, a first type of resin 412a photopolymerizes at a first wavelength of 405 nm, and a second type of resin 412b154854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) photopolymerizes at a second wavelength of 365 nm. In embodiments, the photopolymerized first type of resin is neutral and the photopolymerized second type of resin has a charge.

[0096] In embodiments, the mixture includes a catalyst 320 and a first material. In embodiments, the catalyst 320 and a first material are not included in the mixture and are separately provided. In embodiments, the catalyst 320 includes palladium salts and dimethylamine borane. In embodiments, the first material is a metal (e.g., nickel, copper, iron oxide, to give a few examples). By metal, it will be understood that the metal may be a chemical derivative of a metal, such as an ion, anion, or alloy of the metal, to give a few examples.

[0097] FIGS. 5A-5C are diagrams of an example of electroless deposition in accordance with exemplary’ embodiments of the present invention.

[0098] In embodiments, the catalyst 320 and the first material enable the deposition of the first material onto a photopolymerized resin with a charge, for example, via electroless deposition. Electroless deposition is a chemical process that deposits a metal coating onto a substrate without the use of electrical current, relying on a catalyst to initiate the reaction. In the multi-material 3D printing process, different charged monomers can be programmatically printed. Through precise control of the charge, charged catalyst ions are selectively absorbed onto the 3D patterned polymers, facilitating the selective electroless deposition of metal on 3D printed objects.

[0099] As shown in FIG. 5A, as an example, in embodiments, a crosslinker 520 (e.g., TMPTA) and a charge carrier 522 (e.g., PDD) undergo polymerization to form a negative photopolymer 524 consisting of polyalkyl chains 526. Referring now to FIG. 5C, this forms a 3D structure (E.g., a lattice) having negative components 500 and neutral components 502. As shown in FIG. 5B and 5C, continuing the example, in embodiments a catalyst 528 (e.g.. Pd(II)) interacts with a charged part 522a of the negative components 500, which absorbs ions of the catalyst. Optionally, in embodiments, the components are soaked in DMAB, leading to the generation of a reduced catalyst. In embodiments, a metal plating solution comprising a metal solution is then introduced, leading to a plating of selectively deposited metal 506.

[0100] This catalyst reaction can be written as follows:H2PO2+ 2H++ e~ -> 2H2O + P (5)164854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20)

[0101] FIGs. 6-7 are flow charts showing steps for 3D printing a multi-material object in accordance with exemplary embodiments of the present invention.

[0102] As shown in FIG. 6, in embodiments, steps for 3D printing a multi-material object include step S600 and step S602. At step S600, a mixture is provided in a vat. In embodiments, the mixture comprises a first type of resin (e.g.. aneutral acrylate monomer, to give an example) and a second type of resin (e.g.. a charge epoxy monomer, to give an example). In embodiments, the mixture comprises a first type of resin (e.g., a neutral acrylate monomer, to give an example) a second t pe of resin (e.g., a charge epoxy monomer, to give an example), a catalyst, and a first ty pe of material (e.g., a metal, such as copper, nickel, or iron oxide, to give a few examples). In embodiments, the first type of resin photopolymerizes on exposure to a first wavelength of light (e.g., 405 nm, to give an example). In embodiments, the second type of resin photopolymerizes on exposure to a second wavelength of light (e.g., 365 nm, to give an example). In embodiments, the first type of resin is different than the second type of resin. In embodiments, the first wavelength of light is a different wavelength than the second wavelength of light. In embodiments, the catalyst promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized. In embodiments, after S600, the process continues with S602.

[0103] At step 602, the mixture is exposed to a plurality of patterns of light in succession. In embodiments, at least a portion of the three-dimensional multilateral object is formed as a result. It will be understood that in embodiments, other steps, such as raising the build plate the multi -material object is formed on, may occur, and are within the spirit and scope of the invention.. In embodiments, the first material may be deposited upon the multi-material object. In embodiments, the multi-material object is a three-dimensional multi-material object, such as an electronic circuit, a programmed charged mosaic, or an antenna, to give a few examples.

[0104] In embodiments, steps S600 and S602 are performed using a 3D printer (e.g., 3D printer 100, 200 or 300, to give a few examples).

[0105] As shown in FIG. 7, in embodiments, steps for 3D printing a multi-material object include steps S700, step S702 and step S704. At step S700, a mixture is formed by combining a first type of resin (e.g., a neutral acrylate monomer, to give an example) and a second type of resin (a charge epoxy monomer, to give an example). In embodiments, the mixture is formed by combining the first type of resin, the second type of resin, a first material (e.g., a metal, such as copper, nickel, or iron oxide, to give a few examples), and a catalyst. In embodiments, the mixture is formed in a vat of a 3D printer. In embodiments, the mixture is formed outside of a174854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) vat of a 3D printer. In embodiments, the first type of resin photopolymerizes on exposure to a first wavelength of light (e.g., 405 nm, to give an example). In embodiments, the second type of resin photopolymerizes on exposure to a second wavelength of light (e.g., 365 nm, to give an example). In embodiments, the first type of resin is different than the second type of resin. In embodiments, the first wavelength of light is a different wavelength than the second wavelength of light. In embodiments, the catalyst promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized. In embodiments, after S700, the process continues with S702 or with S704. In embodiments, the process continues with S702 and S704 simultaneously.

[0106] At step S702, the process continues by exposing the mixture to a pattern of light at the first wavelength. In embodiments, this causes the first type of resin to photopolymerize in a shape defined by the pattern of light. In embodiments, the process can then continue with the mixture being exposed to a subsequent image, or the process can end. In embodiments, the process continues with step S702 (e.g., exposure to a different pattern of light at the first wavelength, after the position of a printing plate has been moved). In embodiments, the process continues with step S704.

[0107] At step S704, the process continues by exposing the mixture to a pattern of light at the second wavelength. In embodiments, this causes the second type of resin to photopolymerize in a shape defined by the pattern of light. In embodiments, for example where the mixture includes the catalyst and the first material, the first material may be deposited on the photopolymerized second type of resin. In embodiments, the process continues with step S704 (e.g., exposure to a different pattern of light at the second w avelength, after the position of a printing plate has been moved). In embodiments, the process continues with step S702.

[0108] In embodiments, at least a portion of the three-dimensional multilateral object is formed as a result. It will be understood that in embodiments, other steps, such as raising the build plate the multi-material object is formed on, may occur, and are within the spirit and scope of the invention.. In embodiments, the multi-material object is a three-dimensional multi -material object, such as an electronic circuit, a programmed charged mosaic, or an antenna, to give a few examples.

[0109] In embodiments, steps S700, S702 and S704 are performed using a 3D printer (e.g., 3D printer 100. 200 or 300, to give a few examples). For example, the patterns of light may be generated using LED 216 and modulator 226. As another example, the patterns of light may be generated using light source 316.184854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20)

[0110] In embodiments, steps S602 and S702 and S704 may continue by a process for plating the three-dimensional multi-material object. In embodiments, at step S604, a catalyst is provided. In embodiment, the process continues with step S606. In embodiments, at step S606, a chemical reductant is optionally provided. In embodiments, the process may continue with step S608, either directly from step S604 or step S606. In embodiments, at step S608, a first material (e.g., a metal such as copper, to give an example) is provided, allowing electroless plating to occur. It will be understood that in embodiments, other steps, such as raising the build plate the multi-material obj ect is formed on, occur and are within the spirit and scope of the invention.

[0111] FIG. 4B provides CAD models, and corresponding photographs, of 3D printed structures in accordance with exemplary embodiments of the present invention. FIG. 4B depicts three CAD models (CAD models 410, 412, and 414). CAD model 410 is a design for a lattice cube fully composed of a neutral material 400. CAD model 412 is a design for a lattice cube composed of both neutral material 400 and charged material 402 (e.g., a programmed charged mosaic). CAD model 410 depicts a cube fully composed of charged material 402. In embodiments, CAD models may be generated using drafting software. In embodiments, CAD models may be converted into computer-readable instructions, such as print instructions, to be provided to a three-dimensional printer in order to fabricate corresponding 3D structures. In embodiments, such instructions may be encoded using G-code (also known as geometric code) and / or other formats, including standard gerber format.

[0112] 3D structure 410a corresponds to CAD model 410 and consists of a lattice cube fully made of a dielectric material 404 (corresponding to the neutral material 400). 3D structure 412a corresponds to CAD model 412 and consists of a lattice cube with an interior lattice made of metal 406 (copper, deposited over the charged material) and an outer frame made a dielectric material 404 (corresponding to the neutral material 400). 3D structure 414a corresponds to CAD model 414 and consists of a lattice cube fully made of copper metal 406, deposited over the charged material. In embodiments, by programming the proj ected images, a lattice structure with an arbitrarily designed circuit can be constructed or otherwise fabricated.

[0113] FIGs. 8, 10 and 11 relate to a reactivity-controlled multi-material 3D printing systems and methods that enables the formation of compositionally varied materials within a single vat, utilizing a single-wavelength light source for photopolymerization in accordance with exemplary embodiments of the present invention. Such systems and methods leverage the differences in reactivity ratios between two distinct monomers to achieve spatially controlled194854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) material variation. They also allow fabrication of 3D-printed structures with programmable material properties and localized charge functionalities after post-processing, such as solvent washing. The approach provides a scalable and efficient route to multi-material 3D printing using a simplified, single-vat, single-wavelength system.

[0114] In embodiments, a first monomer, neutral in charge, is selected for its high polymerization rate and strong tendency toward self-polymerization. In embodiments, the first monomer is an acrylate-group monomer. In embodiments, the first monomer is selected so as to polymerize at both low and high exposure energies. In embodiments, with higher exposure energy, the conversion rate increases.

[0115] In embodiments, a second monomer, carrying a negative charge and characterized by a relatively low polymerization rate, is selected such that its self-reactivity ratio (rn) is lower than its cross-reactivity with the first monomer (J12), i.e., rn / ri2 < 1. In embodiments, the second monomer preferentially polymerizes in an alternating manner (for example, the second monomer may tend to polymerize in combination with the first monomer). In embodiments, the second monomer is selected so as to have a lower conversion rate at low exposure energy, but significantly higher conversation rates at higher exposure energy. In embodiments, this may be due to the higher concentration of the monomer.

[0116] As illustrated in FIG. 8, discussed in further detail below, in embodiments, when exposed to a single-wavelength light source, regions subjected to lower exposure energy primarily initiate polymerization of the neutral monomer, resulting in areas predominantly composed of the corresponding material. In regions exposed to higher energy7, rapid consumption of the neutral monomer occurs, facilitating the incorporation of the negatively charged monomer into the polymer network. This exposure-dependent polymerization behavior enables the formation of spatially distinct material domains within a single printed object. For example, the inventors have observed that the acry late monomer polymerizes first, while the methacry late monomer requires a significantly higher exposure energy to initiate polymerization. The required exposure energy7for methacrylate polymerization can be 3 to 5 times greater than that for the acrylate monomer.

[0117] In embodiments, exposure energy is determined by the product of light intensity and exposure time. In embodiments, light intensity7is an adjustable parameter of the projector. For example, a standard intensity may be 0.9 mW / cm2, though it can be easily modified as needed. In embodiments, the exposure time can also be modified, for example, by modifying204854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) the total length of exposure and / or by modifying the duty cycle of the waveforms projected by the projector.[01 1 8] Tn embodiments, the wavelength of light used is selected such that it matches the absorption spectrum of the photo initiator being used. The wavelength selected may depend also on the projector being used. In embodiments, the 365 nm wavelength is broad, typically within a 40 nm range (e.g., 345-385 nm). However, in embodiments, the 405 nm projector may require a much narrower wavelength range, such as 395-415 nm, to ensure proper performance. Since most modem projectors have broader spectral outputs, in embodiments, optical fdters are used to narrow the emission spectrum, particularly for the 405 nm wavelength.

[0119] FIG. 8 is a diagram illustrating the use of a 3D printer to 3D printing a multimaterial object involving a single light source projecting a single wavelength of light in accordance with exemplary' of the present invention.

[0120] As shown in FIG. 8, the process includes using a stereolithographic printer (e.g., stereolithographic printer 800) to 3D print a multi-material object (e.g., multi -material object 810. In embodiments of the present invention, the stereolithographic printer (e.g., stereolithographic printer 800) includes components similar to the stereolithographic printer 100, 200. and 300. In embodiments, the stereolithographic printer (e.g., printer 800) includes one or more light sources and / or optics (e.g., light source 816), which may include, for example, LEDs, UV light generators, focusing lenses, and mirrors, configured to project one or more light images, as shown by light projection 802. In embodiments, the light source is configured to generate multiple wavelengths of light (e.g., infrared, visible, and ultraviolet light, to give a few examples). In embodiments, the wavelengths may be selected from a band (e.g., between 395 and 415 nm, to give an example). In embodiments the stereolithographic printer includes a vat (e.g., vat 806).

[0121] In embodiments, the vat is used to store a mixture (e.g., mixture 812). In embodiments, the mixture may be homogenously mixed. In embodiments, the mixture is created by combining components of the mixture in the vat. In embodiments, the mixture is created by combining components of the mixture outside of the vat. In embodiments, the mixture includes a plurality' of types of resins.

[0122] In embodiments, at least one of the types of resin is a monomer. In embodiments, the first type of resin comprises an acrylate-group monomer (e.g., Trimethylolpropane triacrylate, “TMPTA”). In embodiments, the second type of resin comprises a methacrylate214854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) group monomer. The methacrylate-group monomer exhibits a lower reactivity ratio and slower polymerization rate, owing to its more stabilized radical structure. In contrast, the acrylategroup monomer has a higher reactivity ratio and polymerizes more rapidly due to its less stable radical structure.

[0123] In embodiments, the wavelength of the light source depends on the monomers used. For example, for both methacrylate and acrylate group monomers, the wavelength of light can be 365 nm, 405 nm, or any other wavelength that matches the absorption spectrum of both photo initiators used.

[0124] In embodiments, the first type of resin has a neutral charge. In embodiments, the second type of resin has a charge (e.g., a positive or negative charge). In embodiments, the first type of resin photopolymerizes by free radical polymerization. In embodiments, the second type of resin photopolymerizes by free radical polymerization.

[0125] In embodiments, the photopolymerization of the plurality of resin creates a multimaterial 3D structure (e.g.. 3D structure 810 composed of monomers 818 and 820). In embodiments, the photopolymerization of the second type of resin creates a negative photopolymer (e.g., negative monomer 818). In embodiments, the negative photopolymer provides a surface for the deposition of one or more materials (e.g., a metal such as copper).

[0126] In embodiments, polymerization is performed under varying exposure energies, which, as FIG. 8 demonstrates, and as discussed, leads to different conversion rates of the monomers. As demonstrated in FIG. 8, as exposure energy increases from low to high, the conversation rate increases. Because the negative monomer has a low conversation rate at low energy exposure, it does not polymerize. However, at higher energy levels, it begins to polymerize. Thus, in embodiments, regions exposed to higher energy may have charged monomer / photopolymers 818 in addition to neutral monomers 820. This provides a surface for plating. For example, after washing, electroless plating may be used to deposit metals along the surface of the multi -material object corresponding to the portions exposed to higher energy and containing a charged monomer.

[0127] FIG. 9 is a diagram illustrating the manufacturing process of three-dimensional multi -material objects 3D printed in accordance with exemplary embodiments of the present invention. It will be understood that the principles and techniques discussed with respect to FIG. 9 are applicable to other types of multi-material objects besides the circuit board depicted, such as antennas, in accordance with exemplary embodiments of the present invention.224854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20)

[0128] The three-dimensional multi-material object (e.g., the circuit) is first designed, for example, using CAD software (e g., KICAD. EAGLE. ORCAD, PROTEUS, CIRCUITMAKER, AUTODESK Fusion 360, PROTEUS, CIRCUITMAKER, SOLIDWORKS, BLENDER, MAYA, SKETCHUP, AUTOCAD, TINKERCAD, to name a few examples) to create a CAD model. In embodiments, the CAD model is a digital representation of a multi-material object. For example, as illustrated in FIG. 9, in embodiments the CAD model may be a digital representation of a circuit. As other examples, in embodiments, the CAD model is a digital representation of a programmed charged mosaic and / or an antenna, to name a couple. In embodiments, the CAD model may include digital representations of different materials, corresponding to the charged and neutral monomers.

[0129] In embodiments, the CAD model, which may be stored as a design file is obtained by a computing computer system, such as computer or other computing devices (e.g., computer 902). In embodiments, the CAD model is created and stored on the computing device.

[0130] A computer or computer system typically includes one or more processors as well as a a variety of computer-readable media. Computer-readable media can be any available media that can be accessed by the computer and includes both volatile and nonvolatile media, removable and non-removable media. By way of example, and not limitation, computer readable media can include computer storage media and communication media. Computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, RAM. ROM, EEPROM, flash memory or other memory technology, CD- ROM, digital video disk (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by the computer.

[0131] Communication media typically embodies computer-readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism, and includes any information delivery media. The term ‘'modulated data signal” means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, RF. cellular, infrared and other wireless234854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) media. Combinations of the any of the above should also be included within the scope of computer-readable media.

[0132] In embodiments, the computer system may also include a display device (e.g., a monitor) and one or more input devices (e.g., mouse and keyboard, to give an example). The computer system may also have an output device, such as a usb port, that enable the computer system to be operably connected, and transmit information to, a three-dimensional printer. Additionally, or alternatively, the computer system may be configured to store, for example via external memory like a USB stick, information, which can then be removed and plugged into the three-dimensional printer.

[0133] In embodiments, the computer system is used to generate a print filed based upon the CAD design file. In embodiments, software, such as slicer software (e.g., SLIC3R, CURA, OCTOPRINT, KISSSLICER, PRUSASLICER, SELFCAD, ICESL, MANGO3D, LYCHEE, TINKERINE, to name a few), may be used to generate the print file. In embodiments, the slicer software is the same as the CAD software. In embodiments, the slicer software is stored on the same computer as the CAD software.

[0134] In embodiments, the print file includes code such as G-code and / or other machine- readable instructions. In embodiments, the print file includes encodings of greyscale patterns 904 converted from the CAD model that serve as dynamic photomasks for the 3D printing process. It will be understood that the print file may include multiple files (e.g.. one or more files including grayscale patterns 904 to be used as dynamic photomasks and one or more files including other instructions, to give an example).

[0135] In embodiments, the print file contains machine-readable instructions which, when executed by a three-dimensional printer 906 (e.g., by a controller operably connected to components of the three-dimensional printer such as the light source and elevator, to name a few), cause the light source to project patterns of light in accordance with exemplary embodiments of the present invention. For example, in embodiments, the machine-readable instructions may cause the light source to project light so as to expose the resin to one or more patterns of light in accordance with step S602 of FIG. 6, steps S702 and S704 of FIG. 7, step S1002 of FIG. 10, and steps S1102 and S1104 of FIG. 11.

[0136] In embodiments, through printing, a multi-material obj ect, such as a charged mosaic pattern 908 is fabricated. The charged mosaic pattern includes photopolymerized neutral monomers and photopolymerized negative monomers, in accordance with exemplary embodiments of the present invention. An advantage of the present invention is that such a244854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) charged mosaic pattern may be fabricated using continuous, high-throughput printing, since the need to change resins and vats is minimized.

[0137] FIGs. 10 and 1 1 are flow charts showing steps for reactivity-controlled multimaterial 3D printing in accordance with exemplary embodiments of the present invention. Specifically, these focus on the printing process itself.

[0138] As shown in FIG. 10. in embodiments, steps for 3D printing a multi-material object include step SI 000 and step SI 002. At step SI 000, a mixture is provided in a vat. In embodiments, the mixture comprises a first type of resin (e.g., a neutral acrylate monomer, to give an example) and a second type of resin (e.g., a charged methacrylate monomer, to give an example). In embodiments, the mixture comprises a first type of resin (e.g., a neutral acrylate monomer, to give an example) a second type of resin (e.g., a charged methacrylate monomer, to give an example), a catalyst, and a first type of material (e.g., a metal, such as copper, nickel, or iron oxide, to give a few' examples). In embodiments, the first type of resin and the second type of resin photopolymerizes on exposure to a first wavelength of light (e.g., 405 nm, to give an example). It w ill be appreciated the wavelength may vary and may be selected as a band of wavelengths. In embodiments, the first type of resin is different than the second type of resin. In embodiments, the first type of resin photopolymerizes at a first polymerization rate on exposure to a first wavelength of light at a first exposure energy'. In embodiments, the second type of resin photopolymerizes at a second polymerization rate on exposure to the first wavelength of light at a second exposure energy. In embodiments, the second type of resin has a self-reactivity ratio that is lower than its cross reactivity' with the first monomer. In embodiments, the catalyst promotes the deposition of the first material upon the second ty pe of resin after the second type of resin is photopolymerized. In embodiments, after S1000, the process continues with S I 002.

[0139] At step SI 002, the mixture is exposed to a plurality of patterns of light in succession. In embodiments, a first pattern of light of the plurality of patterns of light is projected at a first intensity by a light source of the three-dimensional printer for a first period of time. In embodiments, a second pattern of light of the plurality of patterns of light is projected at a second intensity by the light source for a second period of time.

[0140] In embodiments, the first intensity as the same as the second intensity, and the first period of time is . In embodiments, the first intensity

[0141] In embodiments, at least a portion of the three-dimensional multilateral object is formed as a result. It will be understood that in embodiments, other steps, such as raising the254854-2293-8064v.3Atorney Docket # 00495-0026 (B2025-20) build plate the multi-material object is formed on, may occur, and are within the spirit and scope of the invention. In embodiments, the first material may be deposited upon the multimaterial object. In embodiments, the multi-material object is a three-dimensional multimaterial object, such as an electronic circuit, a programmed charged mosaic, or an antenna, to give a few examples.

[0142] In embodiments, steps S 1000 and S1002 are performed using a 3D printer (e.g., 3D printer 100, 200, 300 and / or 800, to give a few examples). In embodiments, such steps are stored as instructions in a print file which can be executed by the 3D printer. In embodiments, the print file may be generated by a computing based upon a design file (e.g., a CAD file) corresponding to a digital representation of the three-dimensional multi-material object.

[0143] As shown in FIG. 1 1, in embodiments, steps for 3D printing a multi-material object include steps SHOO, step SI 102 and step SI 104. At step SHOO, a mixture is formed by combining a first type of resin (e.g., a neutral acrylate monomer, to give an example) and a second type of resin (a charged methacrylate monomer, to give an example). In embodiments, the mixture is formed by combining the first type of resin, the second type of resin, a first material (e g., a metal, such as copper, nickel, or iron oxide, to give a few examples), and a catalyst. In embodiments, the mixture is formed in a vat of a 3D printer. In embodiments, the mixture is formed outside of a vat of a 3D printer. In embodiments, the first type of resin and the second type of resin photopolymerizes on exposure to a first wavelength of light (e.g., 405 nm, to give an example). In embodiments, the first type of resin photopolymerizes at a first polymerization rate on exposure to a first wavelength of light at a first exposure energy. In embodiments, the second type of resin photopolymerizes at a second poly merization rate on exposure to the first wavelength of light at a second exposure energy. In embodiments, the second type of resin has a self-reactivity ratio that is lower than its cross reactivity with the first monomer. In embodiments, the catalyst promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized. In embodiments, after SI 100, the process continues with SI 102 or with SI 104.

[0144] At step S 1102. the process continues by exposing the mixture to a patern of light at the first wavelength at a first intensity for a first period of time. In embodiments, this causes the first type of resin to photopolymerize in a shape defined by the pattern of light. In embodiments, the first intensity and / or the first period of time are selected so as to polymerize the first resin but not significant amounts of the second resin (i.e.. to keep the exposure energy of the second resin low enough to avoid polymerization). In embodiments, the process can then264854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) continue with the mixture being exposed to a subsequent image, or the process can end. In embodiments, the process continues with step SI 102 (e.g.. exposure to a different pattern of light at the first wavelength, keeping the exposure energy below the threshold to polymerize the second resin, after the position of a printing plate has been moved). In embodiments, the process continues with step SI 104.

[0145] At step S1104, the process continues by exposing the mixture to a pattern of light at the first wavelength at a second intensity for a second period of time. In embodiments, this causes both the first and the second type of resin to photopolymerize in a shape defined by the pattern of light. In embodiments, the second intensity7and / or the second period of time are selected so as to polymerize the first resin and the second resin (i.e.. to raise the exposure energy of the second resin high enough to promote polymerization). In embodiments, for example, where the mixture includes the catalyst and the first material, the first material may be deposited on the photopolymerized second type of resin. In embodiments, the process continues with step SI 104 (e.g., exposure to a different pattern of light, keeping the exposure energy above the threshold to polymerize the second resin, after the position of a printing plate has been moved). In embodiments, the process continues with step SI 102.

[0146] In embodiments, the first intensity7, second intensity7, first period of time and second period of time may be selected so as to promote the formation of the multi-material object in a precise manner and control the composition of the multi-material object. In embodiments, such a selection depends on relative polymerization rates and reactivities of monomers in the first resin and the polymerization rate of monomers in the second resin.

[0147] In embodiments, at least a portion of the three-dimensional multilateral object is formed as a result. It will be understood that in embodiments, other steps, such as raising the build plate the multi-material object is formed on, may occur, and are within the spirit and scope of the invention. In embodiments, the first material may be deposited upon the multimaterial object. In embodiments, the multi-material object is a three-dimensional multimaterial object, such as an electronic circuit, a programmed charged mosaic, or an antenna, to give a few examples.

[0148] In embodiments, the multi-material object is a three-dimensional multi-material object, such as an electronic circuit, a programmed charged mosaic, or an antenna, to give a few examples.

[0149] In embodiments, steps SHOO, SI 102 and SI 104 are performed using a 3D printer (e.g., 3D printer 100, 200 or 300, to give a few examples). For example, the patterns of light274854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) may be generated using LED 216 and modulator 226. As another example, the patterns of light may be generated using light source 316 or 816.

[0150] In embodiments, subsequent exposure of the printed structure to a metal ion solution enables selective metal deposition onto the charged regions, resulting in the assembly of functional circuits directly onto the printed object.

[0151] Referring back to FIGs. 8 and 9, following printing of the three-dimensional multimaterial object, additional processing may occur. For example, in embodiments, after printing, the three-dimensional multi-material object may be washed and or otherwise cleaned to remove resin and unpolymerized material, or material not intended to be included in the final printed object, as illustrated in FIG 8. As illustrated in FIG. 9, after a multi -material object is printed and / or washed (such as printed charged mosaic 908, to give an example), the multi-material object may undergo solution plating. For example, in embodiments, steps S1002 and SI 102 and SI 104 may continue by a process for plating the three-dimensional multi-material object, as discussed herein and with respect to steps S604, S606 and S608 of FIG. 6. Referring back to FIG. 9, in embodiments, the solution plating may be performed using an aqueous plating solution 910. In embodiments, the aqueous plating solution includes a metal to be deposited on the portions of the three-dimensional multi -material object. In embodiments, after plating, a coated sample 912 or other three-dimensional multi -material object is produced (e.g., a circuit board).

[0152] Now that embodiments of the present invention have been shown and described in detail, various modifications and improvements thereon can become readily apparent to those skilled in the art. Accordingly, the exemplary' embodiments of the present invention, as set forth above, are intended to be illustrative, not limiting. The spirit and scope of the present invention is to be construed broadly.284854-2293-8064v.3

Claims

Attorney Docket # 00495-0026 (B2025-20)CLAIMS:What is claimed is:

1. A method for 3D printing a multi -material object comprising the steps of:(a) providing a mixture comprising a first type of resin and a second type of resin in a vat, wherein: i. the first type of resin photopotymerizes on exposure to a first wavelength of light; ii. the second type of resin photopolymerizes on exposure to a second wavelength of light; iii. the first type of resin is different than the second type of resin; and iv. the first wavelength of light is a different wavelength than the second wavelength of light; and(b) exposing the mixture to a plurality of patterns of light in succession, wherein at least a first pattern of light is projected at the first wavelength and at least a second pattern is projected at the second wavelength, wherein the multi-matenal object is formed as a result.

2. A method for 3D printing a multi -material object comprising:(a) providing a mixture comprising a first type of resin, a second type of resin, a catalyst, and a first material in a vat, wherein: i. the first type of resin photopotymerizes on exposure to a first wavelength of light; ii. the second type of resin photopotymerizes on exposure to a second wavelength of light; iii. the first wavelength of light is a different wavelength than the second wavelength of light; and iv. the catalyst promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized;(b) exposing the mixture to a plurality of patterns of light in succession, wherein each pattern of light is projected at a wavelength selected from the first wavelength or the second wavelength, wherein the multi-material object is formed as a result.

3. A method for 3D printing a multi -material object comprising the steps of:(a) forming a mixture by combining:294854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) i. a first type of resin which photopolymerizes on exposure to a first wavelength of light; and ii. a second type of resin which photopolymerizes on exposure to a second wavelength of light, wherein the first ty pe of resin is different than the second ty pe of resin and the first wavelength of light is a different wavelength than the second wavelength of light;(b) exposing the mixture in a vat to a first pattern of light at the first wavelength; and(c) exposing the mixture in the vat to a second pattern of light at the second wavelength, wherein the multi-material object is formed as a result.

4. A method for 3D printing a multi -material object comprising the steps of:(a) forming a mixture by combining: i. a first type of resin which photopolymerizes on exposure to a first wavelength of light; ii. a second type of resin which photopolymerizes on exposure to a second wavelength of light; iii. a first material; iv. and a catalyst which promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized; wherein the first type of resin is different than the second type of resin and the first wavelength of light is a different wavelength than the second wavelength of light;(b) exposing the mixture in a vat to a first pattern of light at the first wavelength; and(c) exposing the mixture in the vat to a second pattern of light at the second wavelength, wherein the multi-material object is formed as a result.

5. The method of any one of claims 1-4, wherein the first wavelength is 405 nm and the second wavelength is 365 nm.

6. The method of any one of claims 1-4, wherein the first type of resin and the second type of resin are homogeneously mixed in the vat.304854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20)7. The method of any one of claims 1-4, wherein the first type of resin has a neutral charge and the second type of resin has a positive or negative charge.

8. The method of any one of claims 1-4, wherein the first type of resin is a neutral acrylate monomer and the second type of resin is a charged epoxy monomer.

9. The method of any one of claims 1-4, wherein the first type of resin photopolymerizes by ring opening polymerization.

10. The method of any one of claims 1-4, wherein the second type of resin photopolymerizes by free radical polymerization.

11. The method of any one of claims 1 or 3, wherein the method further comprises providing a metal and a catalyst which promotes deposition of the metal on the photopolymerized second type of resin.

12. The method of any one of claims 1-4, wherein the multi -material object comprises a three-dimensional circuit.

13. The method of any one of claims 1-4, wherein the multi-material object comprises a programmed charged mosaic.

14. The method of any one of claims 2 or 4. wherein the first material is a metal.

15. The method of claim 14, wherein the metal is Nickel.

16. The method of claim 14, wherein the metal is Copper.

17. The method of claim 14, wherein the metal is Iron Oxide.

18. The method of any one of claims 3 or 4, wherein step (b) is performed before step (c).

19. The method of any one of claims 3 or 4, wherein step (b) is performed after step (c).

20. The method of any one of claims 3 or 4, wherein step (b) is performed before and after step (c).

21. The method of any one of claims 3 or 4, wherein step (c) is performed before and after step (b).

22. A three-dimensional multi-material object created by the process comprising:(a) providing a mixture comprising a first type of resin and a second type of resin in a vat. wherein: i. the first type of resin photopolymerizes on exposure to a first wavelength of light; ii. the second type of resin photopolymerizes on exposure to a second wavelength of light; iii. the first type of resin is different than the second type of resin; and314854-2293-8064v.3Atorney Docket # 00495-0026 (B2025-20) iv. the first wavelength of light is a different wavelength than the second wavelength of light; and(b) exposing the mixture to a plurality of patterns of light in succession, wherein at least a first pattern of light is projected at the first wavelength and at least a second pattern is projected at the second wavelength, wherein the three-dimensional multi -material object is formed as a result.

23. A three-dimensional multi-material object created by the process comprising:(a) providing a mixture comprising a first type of resin, a second type of resin, a catalyst, and a first material in a vat, wherein: i. the first type of resin photopolymerizes on exposure to a first wavelength of light; ii. the second type of resin photopolymerizes on exposure to a second wavelength of light; iii. the first wavelength of light is a different wavelength than the second wavelength of light; and iv. the catalyst promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized;(b) exposing the mixture to a plurality of patterns of light in succession, wherein each pattern of light is projected at a wavelength selected from the first wavelength or the second wavelength, wherein the three-dimensional multi -material object is formed as a result.

24. A three-dimensional multi-material object created by the process comprising:(a) forming a mixture by combining: i. a first type of resin which photopolymerizes on exposure to a first wavelength of light; and ii. a second type of resin which photopolymerizes on exposure to a second wavelength of light, wherein the first type of resin is different than the second type of resin and the first wavelength of light is a different wavelength than the second wavelength of light;(b) exposing the mixture in a vat to a first pattern of light at the first wavelength; and(c) exposing the mixture in the vat to a second patern of light at the second wavelength,324854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) wherein the three-dimensional multi -material object is formed as a result.

25. A three-dimensional multi-material object created by the process comprising:(a) forming a mixture by combining: i. a first type of resin which photopolymerizes on exposure to a first wavelength of light; ii. a second type of resin which photopolymerizes on exposure to a second wavelength of light: iii. a first material; iv. and a catalyst which promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized; wherein the first type of resin is different than the second type of resin and the first wavelength of light is a different wavelength than the second w avelength of light;(b) exposing the mixture in a vat to a first pattern of light at the first wavelength; and(c) exposing the mixture in a vat to a second pattern of light at the second wavelength.

26. The three-dimensional multi-material object of any one of claims 22-25, wherein the three-dimensional multi-material object comprises an electronic circuit.

27. The three-dimensional multi-material object of any one of claims 22-25, wherein the three-dimensional multi-material object comprises a programmed charged mosaic.

28. The three-dimensional multi-material object of any one of claims 22-25, wherein the three-dimensional multi-material object comprises an antenna.

29. The three-dimensional multi-material object of any one of claims 22-25, wherein the mixture is formed in the vat.

30. The three-dimensional multi-material object of any one of claims 22-25, wherein the first wavelength is 405 nm and the second wavelength is 365 nm.

31. The three-dimensional multi-material object of any one of claims 22-25, wherein the first type of resin and the second ty pe of resin are homogeneously mixed in the vat.

32. The three-dimensional multi-material object of any one of claims 22-25, wherein the first type of resin has a neutral charge and the second type of resin has a positive or negative charge.334854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20)33. The three-dimensional multi-material object of any one of claims 22-25, wherein the first type of resin is a neutral acrylate monomer and the second type of resin is a charged epoxy monomer.

34. The three-dimensional multi-material object of any one of claims 22-25, wherein the first type of resin is configured to photopolymerize by ring opening polymerization.

35. The three-dimensional multi-material object of any one of claims 22-25, wherein the second type of resin is configured to photopolymerize by free radical polymerization.

36. The three-dimensional multi -material object of any one of claims 22 or 24, wherein the method further comprises providing a metal and a catalyst which promotes deposition of the metal on the photopolymerized second type of resin.

37. The three-dimensional multi-material object of any one of claims 23 or 25, wherein the first material is a metal.

38. The three-dimensional multi-material object of claim 37, wherein the metal is Nickel.

39. The three-dimensional multi-material object of claim 37, wherein the metal is Copper.

40. The three-dimensional multi-material object of claim 37, wherein the metal is IronOxide.

41. The three-dimensional multi-material object of any one of 24 or 25, wherein step (b) is performed before step (c).

42. The three-dimensional multi-material object of any one of 24 or 25, wherein step (b) is performed after step (c).

43. The three-dimensional multi-material object of any one of 24 or 25, wherein step (b) is performed before and after step (c).

44. The three-dimensional multi-material object of any one of 24 or 25, wherein step (c) is performed before and after step (b).

45. A method for 3D pnnting a multi-material object comprising the steps of:(a) providing a mixture comprising a first type of resin and a second type of resin in a vat, wherein: i. the first type of resin photopolymerizes at a first polymerization rate on exposure to a first wavelength of light at a first exposure energy; ii. the second type of resin photopolymerizes at a second polymerization rate on exposure to the first wavelength of light at a second exposure energy: iii. the first type of resin is different than the second type of resin; and344854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) iv. the first polymerization rate is higher than the second polymerization rate: and(b) exposing the mixture to a plurality of patterns of light in succession, wherein at least a first pattern of light is projected at a first intensity by a light source for a first period of time and at least a second pattern is projected by the light source at a second intensity for a second period of time, wherein the multi-material object is formed as a result.

46. A method for 3D printing a multi-material object comprising:(a) providing a mixture comprising a first type of resin, a second type of resin, a catalyst, and a first material in a vat, wherein: i. the first type of resin photopolymerizes at a first polymerization rate on exposure to a first wavelength of light at a first exposure energy: ii. the second type of resin photopolymerizes at a second polymerization rate on exposure to the first wavelength of light at a second exposure energy: hi. the first type of resin is different than the second type of resin: and iv. the first polymerization rate is higher than the second polymerization rate; and v. the catalyst promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized; and(b) exposing the mixture to a plurality of patterns of light in succession, wherein at least a first pattern of light is projected at a first intensity by a light source for a first period of time and at least a second pattern is projected at a second intensity by a light source for a second period of time, wherein the multi-material object is formed as a result.

47. A method for 3D printing a multi-material object comprising the steps of:(a) forming a mixture by combining: i. a first type of resin which photopolymerizes at a first polymerization rate on exposure to a first wavelength of light; and ii. a second type of resin which photopolymerizes at a second polymerization rate on exposure to the first wavelength of light, wherein the first type of resin is different than the second type of resin and the first polymerization rate is higher than the second polymerization rate;354854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20)(b) exposing the mixture in a vat to a first pattern of light projected by a light source at the first wavelength at a first intensity for a first period of time; and(c) exposing the mixture in the vat to a second pattern of light projected by the light source at the first wavelength at a second intensity for a second period of time, wherein the multi-material object is formed as a result.

48. A method for 3D printing a multi-material object comprising the steps of:(a) forming a mixture by combining: i. a first type of resin which photopolymerizes at a first polymerization rate on exposure to a first wavelength of light at a first exposure energy’; ii. a second type of resin which photopolymerizes at a second polymerization rate on exposure to the first wavelength of light at a second exposure energy ; iii. a first material; iv. and a catalyst which promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized; wherein the first type of resin is different than the second type of resin and the first polymerization rate is higher than the second polymerization rate;(b) exposing the mixture in a vat to a first pattern of light projected by a light source at the first wavelength at a first intensity for a first period of time; and(c) exposing the mixture in the vat to a second pattern of light projected by the light source operating on a second duty cycle at the first wavelength at a second intensity for a second period of time, wherein the multi-material object is formed as a result.

49. The method of any one of claims 45-48, wherein the first wavelength is between 395 and 415 nm.

50. The method of any one of claims 45-48, wherein the first type of resin and the second type of resin are homogeneously mixed in the vat.

51. The method of any one of claims 45-48, wherein the first type of resin has a neutral charge and the second type of resin has a positive or negative charge.

52. The method of any one of claims 45-48, wherein the first type of resin is a neutral acrylate monomer and the second type of resin is a charged methacrylate monomer.364854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20)53. The method of any one of claims 45-48, wherein the first type of resin photopolymerizes by free radical polymerization.

54. The method of any one of claims 45-48, wherein the second type of resin photopolymerizes by free radical polymerization.

55. The method of any one of claims 45 or 47, wherein the method further comprises providing a metal and a catalyst which promotes deposition of the metal on the photopolymerized second type of resin.

56. The method of any one of claims 45 or 47, wherein the method further comprises providing a metal ion solution and placing the multi-material object in the metal ion solution, such that metal is deposited onto portions of the multi -material obj ect fabricated upon exposure to light at the first wavelength at the second intensity.

57. The method of claim 56, wherein the metal is Nickel.

58. The method of claim 56, wherein the metal is Copper.

59. The method of claim 56, wherein the metal is Iron Oxide.

60. The method of any one of claims 45-48, wherein the multi-material object comprises a three-dimensional circuit.

61. The method of any one of claims 45-48, wherein the multi-material object comprises a programmed charged mosaic.

62. The method of any one of claims 46 or 48. wherein the first material is a metal.

63. The method of claim 62, wherein the metal is Nickel.

64. The method of claim 62, wherein the metal is Copper.

65. The method of claim 62, wherein the metal is Iron Oxide.

66. The method of any one of claims 47 or 48, wherein step (b) is performed before step (c).

67. The method of any one of claims 47 or 48, wherein step (b) is performed after step (c).

68. The method of any one of claims 47 or 48, wherein step (b) is performed before and after step (c).

69. The method of any one of claims 47 or 48. wherein step (c) is performed before and after step (b).

70. The method of any one of claims 45-48, wherein the first intensity is the same as the second intensity.

71. The method of any one of claims 45-48, wherein the first intensity’ is different than the second intensity.374854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20)72. The method of any one of claims 45-48, wherein the first period of time is the same as the second period of time.

73. The method of any one of claims 45-48, wherein the first period of time is different than the second period of time.

74. A three-dimensional multi-material object created by the process comprising:(a) providing a mixture comprising a first type of resin and a second type of resin in a vat. wherein: i. the first t pe of resin photopolymerizes at a first polymerization rate on exposure to a first wavelength of light at a first exposure energy; ii. the second type of resin photopolymerizes at a second polymerization rate on exposure to the first wavelength of light at a second exposure energy; iii. the first type of resin is different than the second type of resin; and iv. the first polymerization rate is higher than the second polymerization rate: and(b) exposing the mixture to a plurality of patterns of light in succession, wherein at least a first pattern of light is projected at a first intensity by a light source for a first period of time and at least a second pattern is projected at a second intensity by the light source for a second period of time, wherein the three-dimensional multi-material object is formed as a result.

75. A three-dimensional multi-material object created by the process comprising:(a) providing a mixture comprising a first type of resin, a second type of resin, a catalyst, and a first material in a vat, wherein: i. the first type of resin photopolymerizes at a first polymerization rate on exposure to a first wavelength of light at a first exposure energy; ii. the second type of resin photopolymerizes at a second polymerization rate on exposure to the first wavelength of light at a second exposure energy; iii. the first type of resin is different than the second type of resin; and iv. the first polymerization rate is higher than the second polymerization rate; and v. the catalyst promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized; and384854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20)(b) exposing the mixture to a plurality of patterns of light in succession, wherein at least a first pattern of light is projected at a first intensity by a light source for a first period of time and at least a second pattern is projected at a second intensity by a light source for a second period of time, wherein the three-dimensional multi -material object is formed as a result.

76. A three-dimensional multi-material object created by the process comprising:(a) forming a mixture by combining: i. a first type of resin which photopolymerizes at a first polymerization rate on exposure to a first wavelength of light; and ii. a second type of resin which photopolymerizes at a second polymerization rate on exposure to the first wavelength of light, wherein the first type of resin is different than the second type of resin and the first polymerization rate is higher than the second polymerization rate;(b) exposing the mixture in a vat to a first pattern of light projected by a light source at the first wavelength at a first intensity for a first period of time; and(c) exposing the mixture in the vat to a second pattern of light projected by the light source at the first wavelength at a second intensity for a second period of time, wherein the three-dimensional multi -material object is formed as a result.

77. A three-dimensional multi-material object created by the process comprising:(a) forming a mixture by combining: i. a first type of resin which photopolymerizes at a first polymerization rate on exposure to a first wavelength of light at a first exposure energy: ii. a second type of resin which photopolymerizes at a second polymerization rate on exposure to the first wavelength of light at a second exposure energy ; iii. a first material; iv. and a catalyst which promotes the deposition of the first material upon the second type of resin after the second type of resin is photopolymerized; wherein the first type of resin is different than the second type of resin and the first polymerization rate is higher than the second polymerization rate;394854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20)(b) exposing the mixture in a vat to a first pattern of light projected by a light source at the first wavelength at a first intensity for a first period of time; and(c) exposing the mixture in the vat to a second pattern of light projected by the light source operating at the first wavelength at a second intensity for a second period of time, wherein the three-dimensional multi -material object is formed as a result.

78. The three-dimensional multi-material object of any one of claims 74-77, wherein the three-dimensional multi-material object comprises an electronic circuit.

79. The three-dimensional multi-material object of any one of claims 74-77, wherein the three-dimensional multi-material object comprises a programmed charged mosaic.

80. The three-dimensional multi-material object of any one of claims 74-77, wherein the three-dimensional multi-material object comprises an antenna.

81. The three-dimensional multi-material object of any one of claims 74-77, wherein the mixture is formed in the vat.

82. The three-dimensional multi-material object of any one of claims 74-77, wherein the first wavelength is 395 and 415 nm.

83. The three-dimensional multi-material object of any one of claims 74-77, wherein the first t pe of resin and the second type of resin are homogeneously mixed in the vat.

84. The three-dimensional multi-material object of any one of claims 74-77, wherein the first type of resin has a neutral charge and the second type of resin has a positive or negative charge.

85. The three-dimensional multi-material object of any one of claims 74-77, wherein the first type of resin is a neutral acry late monomer and the second type of resin is a charged methacrylate monomer.

86. The three-dimensional multi-material object of any one of claims 74-77, wherein the first type of resin is configured to photopolymerize by free radical polymerization.

87. The three-dimensional multi-material object of any one of claims 74-77, yvherein the second type of resin is configured to photopolymerize by free radical polymerization.

88. The three-dimensional multi-material object of any one of claims 74 or 76, wherein the method further comprises providing a metal and a catalyst which promotes deposition of the metal on the photopolymerized second type of resin.

89. The three-dimensional multi-material object of any one of claims 74 or 76, wherein the three-dimensional multi-material object comprises metal deposited on the surface404854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20) of the multi-material object along portions fabricated upon exposure to light at the first wavelength at the second intensity’.

90. The method of claim 89, wherein the metal is Nickel.

91. The method of claim 89, wherein the metal is Copper.

92. The method of claim 89, wherein the metal is Iron Oxide.

93. The three-dimensional multi-material object of any one of claims 75 or 77, wherein the first material is a metal.

94. The three-dimensional multi -material object of claim 93, wherein the metal is Nickel.

95. The three-dimensional multi-material object of claim 93, wherein the metal is Copper.

96. The three-dimensional multi-material object of claim 93, wherein the metal is Iron Oxide.

97. The three-dimensional multi-material object of any one of 75 or 77, wherein step (b) is performed before step (c).

98. The three-dimensional multi-material object of any one of 75 or 77, wherein step (b) is performed after step (c).

99. The three-dimensional multi-material object of any one of 75 or 77. wherein step (b) is performed before and after step (c).

100. The three-dimensional multi-material object of any one of 75 or 77, wherein step (c) is performed before and after step (b).

101. A method comprising:(a) obtaining, by a computing device, a design file corresponding to a digital representation of a three-dimensional multi -material object; and(b) generating, by the computing device, a print file based upon the design file, wherein the print file contains machine-readable instructions which, when executed by a three-dimensional printer, cause a light source of the three- dimensional printer to: i. project at least a first pattern of light at a first intensity' at a first wavelength for a first period of time; and ii. project at least a second pattern of light at a second intensity at the first wavelength for a second period of time, wherein the first period of time is less than the second period of time, thereby fabricating at least a portion of the three-dimensional multi -material object.

102. A method comprising:414854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20)(a) obtaining, by a computing device, a design file corresponding to a digital representation of a three-dimensional multi -material object; and(b) generating, by the computing device, a print file based upon the design file, wherein the print file contains machine-readable instructions which, when executed by a three-dimensional printer, cause a light source of the three- dimensional printer to project a plurality of patterns of light in succession, wherein at least a first pattern of light is projected at a first intensity at a first wavelength for a first period of time, wherein at least a second pattern of light is projected at a second intensity' at the first wavelength for a second period of time, and wherein the first period of time is less than the second period of time, thereby fabricating at least a portion of the three-dimensional multimaterial object.

103. A computing device comprising:(a) one or more processors; and(b) a non-transitory computer readable storage medium, wherein the non- transitory computer readable storage medium contains computer readable instructions that, when executed by the one or more processors, cause the one or more processors to generate a print file based upon a design file corresponding to a digital representation of a three-dimensional multi-material object, wherein the print file contains instructions which, yvhen executed by a three-dimensional printer, cause a light source of the three-dimensional printer to: i. project at least a first pattern of light at a first intensity at a first wavelength while the first light source for a first period of time; and ii. project at least a second pattern of light at the first wavelength at a second intensity while the first light source for a second period of time, wherein the first period of time is less than the second period of time, thereby fabricating at least a portion of the three-dimensional multi material object.

104. A computing device comprising:(a) one or more processors; and424854-2293-8064v.3Attorney Docket # 00495-0026 (B2025-20)(b) a non-transitory computer readable storage medium, wherein the non- transitory computer readable storage medium contains computer readable instructions that, when executed by the one or more processors, cause the one or more processors to generate a print file based upon a design file corresponding to a digital representation of a three-dimensional multi-material object, wherein the print file contains instructions which, when executed by a three-dimensional printer, cause a light source of the three-dimensional printer to project a plurality7of patterns of light in succession, wherein at least a first pattern of light is projected at a first intensity at a first wavelength for a first period of time. wherein at least a second pattern of light is projected at a second intensity at the first wavelength for a second period of time, and wherein the first period of time is less than the second period of time, thereby fabricating at least a portion of the three-dimensional multimaterial object.434854-2293-8064v.3

Images