Method and system for forming object by means of additive manufacturing

Abstract

Disclosed in the present application is a method for manufacturing a target object by means of an additive manufacturing system. The method comprises: aligning a forming platform with a first carrying device, and then curing a first material to form a first portion of a first layer, the first portion having a first thickness; aligning the forming platform with a second carrying device, and then curing a second material to form a second portion of the first layer, the second portion of the first layer having a second thickness greater than the first thickness; and aligning the forming platform with the first carrying device again, and then forming a first portion of a second layer on the first portion of the first layer, such that the total thickness of the first portion formed from the first material is greater than that of the second portion formed from the second material.

Description

Methods and systems for forming objects through additive manufacturing

[0001] This application claims priority to Chinese patent application No. 202411553161.3, filed on November 1, 2024, with the Chinese Patent Office; and to Chinese patent application No. 202411553164.7, filed on November 1, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of 3D printing technology, and more specifically, to a 3D printing method and a 3D printing device. Background Technology

[0003] Additive manufacturing technologies come in various types, such as DLP, LCD, SLA, and FDM. To obtain a target object with one part composed of the same material and another part composed of multiple materials (e.g., a cylindrical object with a black base, a left half made of red material, and a right half made of blue material), FDM can print the object using filaments of black, red, and blue materials. However, the printing precision of FDM will exhibit a noticeable stack of multiple layers, which is easily identifiable by the user. Photopolymerization technologies (e.g., DLP, LCD) allow for the generation of high-precision target objects, where the stacked layers are difficult for the user to discern, resulting in good print surface quality. However, photopolymerization technology currently only allows the construction of a first layer composed of a first material and a second layer on top of that first layer composed of a second material different from the first material; achieving printing of two or more materials on the same layer presents challenges. Summary of the Invention

[0004] This application provides a method for manufacturing a target object using an additive manufacturing system, the additive manufacturing system including a forming platform, a radiating device, and at least two support devices located between the forming platform and the radiating device, the method comprising:

[0005] The molding platform is aligned with the first support device of at least two support devices, and then the first material carried by the first support device is cured by a radiation device to form a first portion of a first layer, the first portion of the first layer having a first thickness;

[0006] Align the molding platform with the second support device of at least two support devices, and then cure the second material carried by the second support device by a radiation device to form a second part of the first layer, the second part of the first layer having a second thickness greater than the first thickness;

[0007] Align the molding platform with the first support device again, and then solidify the first material to form the first part of the second layer on the first part of the first layer, such that the total thickness of the first part composed of the first material is greater than the total thickness of the second part composed of the second material.

[0008] Align the molding platform with the second support device again, and then cure the second material to form the second part of the second layer on the second part of the first layer, such that the total thickness of the second part composed of the second material is greater than the total thickness of the first part composed of the first material.

[0009] In some embodiments, the method further includes forming a plurality of stacked layers on the second layer, wherein for each stacked layer, a first portion made of a first material and a second portion made of a second material are alternately formed.

[0010] In some embodiments, after forming n first parts and n second parts, a (n+1)th first part is formed, such that the total thickness of the (n+1)th first part is equal to the total thickness of the n second parts, where n≥2.

[0011] In some embodiments, the method further includes providing a plurality of slice layers of the target object, the plurality of slice layers including an initial slice layer, a plurality of intermediate slice layers and an end slice layer, wherein a first portion of the first layer is formed based on at least one of the initial slice layer or the intermediate slice layers, and the (n+1)th first portion is formed based on at least one of the end slice layer or the intermediate slice layers.

[0012] In some embodiments, the total thickness of the first portion of the first layer and the second layer is equal to the sum of the first thickness and the second thickness.

[0013] In some embodiments, the total thickness of the second portion of the first layer and the second layer is twice the second thickness.

[0014] In some embodiments, the method further includes:

[0015] Align the molding platform with the third support device among at least two support devices, and then cure the third material supported by the third support device by a radiation device to form the third part of the first layer, wherein the third part of the first layer has a third thickness greater than the second thickness;

[0016] Align the molding platform with the third support device again, and then cure the third material to form the third part of the second layer on the third part of the first layer, such that the total thickness of the third part made of the third material is greater than the total thickness of the second part made of the second material.

[0017] In some embodiments, the method further includes forming a plurality of stacked layers on the second layer, wherein for each stacked layer, a first portion made of a first material, a second portion made of a second material, and a third portion made of a third material are alternately formed.

[0018] In some embodiments, after forming n first parts, n second parts, and n third parts, the (n+1)th first part and the (n+1)th second part are formed so that the total thickness of the (n+1)th first part, the total thickness of the (n+1)th second part, and the total thickness of the (n)th third part are the same, where n≥2.

[0019] In some embodiments, the total thickness of the first portion of the first layer and the second layer is equal to the sum of the first thickness and the third thickness.

[0020] In some embodiments, the total thickness of the second portion of the first and third layers is twice the thickness of the third layer.

[0021] In some embodiments, the first thickness is 1% to 99% of the second thickness, for example 30% to 70%, for example 40% to 60%, for example 50%.

[0022] In some embodiments, the second thickness is 5–300 μm, for example 20–200 μm, for example 50–150 μm, for example 60–120 μm.

[0023] In some embodiments, the method further includes: forming at least one target layer of the target object using a target material, wherein a plurality of target layers are formed before the first layer; or a plurality of target layers are formed after the second layer.

[0024] In some embodiments, the target material:

[0025] - Same as the first material, or

[0026] - Same as the second material, or

[0027] -Different from the first material or the second material.

[0028] In some embodiments, a first portion of the second layer is formed on a first portion of the first layer along the construction direction of the target object; and, along a direction perpendicular to the construction direction, the first portion of the first layer is in contact with or spaced apart from the second portion of the first layer.

[0029] In some embodiments, the method further includes:

[0030] After the first part of the first layer is formed, the target object adhered to the forming platform is cleaned; and / or

[0031] After the second part of the first layer is formed, the target object that has adhered to the molding platform is cleaned.

[0032] In some embodiments, the cleaning includes at least one of the following: a rotational molding platform, wiping the target object, applying an airflow to the target object, or surrounding the target object with an adsorption element.

[0033] In some embodiments, at least two support devices further include an additional support device configured to accommodate a cleaning material or a third material that is the same as the first or second material and that is different from the first or second material.

[0034] In some embodiments, the first carrier is a box, and the method further includes supplying a first material to the box so that the box contains a predetermined volume of the first material.

[0035] In some embodiments, the first support device is a plate-like element, and the method further includes applying the first material to the first support device via a nozzle.

[0036] In some embodiments, the method further includes cleaning the first carrier device after forming a first portion of the first layer.

[0037] In some embodiments, aligning the molding platform with a first support device among at least two support devices includes: moving the molding platform or at least one of the first support devices.

[0038] In some embodiments, movement includes at least one of translation or rotation.

[0039] In some embodiments, the thickness of the first material carried by the first support device is 2 to 10 times the thickness of the first material.

[0040] This application also provides an additive manufacturing system for manufacturing a target object, comprising:

[0041] Molding platform;

[0042] Radiation device;

[0043] The first support device is located between the forming platform and the radiation device, and is configured to support the first material;

[0044] The second support device is located between the forming platform and the radiation device, and is configured to support a second material that is different from the first material;

[0045] A drive mechanism configured to align the forming platform with either a first or a second support device; and

[0046] The controller is configured as follows:

[0047] - Align the molding platform with the first support device of at least two support devices, and then cure the first material carried by the first support device by a radiation device to form a first portion of a first layer, the first portion of the first layer having a first thickness;

[0048] - Align the molding platform with the second support device in at least two support devices, and then cure the second material carried by the second support device by a radiation device to form a second part of the first layer, the second part of the first layer having a second thickness greater than the first thickness;

[0049] -Align the molding platform with the first support device again, and then solidify the first material to form the first part of the second layer on the first part of the first layer, such that the total thickness of the first part composed of the first material is greater than the total thickness of the second part composed of the second material.

[0050] - Align the molding platform with the second support device again, and then cure the second material to form the second part of the second layer on the second part of the first layer, such that the total thickness of the second part composed of the second material is greater than the total thickness of the first part composed of the first material.

[0051] This application also provides a 3D printing method, including:

[0052] Align the molding platform with the first material area, and solidify the first material to form a first portion of a predetermined thickness of the target object, wherein the first portion has a first surface close to the molding surface of the molding platform and a second surface away from the molding surface, wherein the first surface is spaced apart from the molding surface by a first distance, and the second surface is spaced apart from the molding surface by a second distance.

[0053] Align the molding platform with the second material area, and solidify the second material to form a second part of the target object with a preset thickness, wherein the second part has a third surface close to the molding surface of the molding platform and a fourth surface away from the molding surface, wherein the third surface is spaced a third distance from the molding surface and the fourth surface is spaced a fourth distance from the molding surface.

[0054] The third distance is within the range of the first and second distances.

[0055] In some embodiments, the 3D printing method further includes:

[0056] After forming a second part of a preset thickness, the molding platform is aligned with the first material area, and the first material of the preset thickness is cured to form an additional first part on the first part, wherein the additional first part has a fifth side close to the molding surface and a sixth side away from the molding surface.

[0057] The fifth surface is flush with the second surface, the fifth surface is separated from the forming surface by a distance of five, and the sixth surface is separated from the forming surface by a distance of six.

[0058] The fourth distance falls within the range of the fifth and sixth distances.

[0059] In some embodiments, the 3D printing method further includes:

[0060] Before forming the first part of the preset thickness, the molding platform is aligned with the second material area, and the second material of the first supplementary thickness is solidified to form an initial supplementary part. The initial supplementary part has a first supplementary surface close to the molding surface of the molding platform and a second supplementary surface away from the molding surface, wherein the first supplementary surface is spaced apart from the molding surface by a first supplementary distance, and the second supplementary surface is spaced apart from the molding surface by a second supplementary distance.

[0061] The first supplementary distance is equal to the first distance, and the second supplementary distance is equal to the third distance.

[0062] This application also provides a three-dimensional printing method configured to be executed by a three-dimensional printing device, wherein the three-dimensional printing device includes a first material region, a second material region, ..., an nth material region, where n≥3, and the three-dimensional printing method includes:

[0063] A first material of at least a first initial supplementary thickness is cured in a first material region, a second material of at least a second initial supplementary thickness is cured in a second material region, ..., and a material of a preset thickness is cured in an nth material region;

[0064] After curing the nth material of a preset thickness, the first material, the second material, ..., the (n-1)th material of a preset thickness are cured in the first material region, the second material region, ..., the (n-1)th material region, respectively.

[0065] The first initial supplementary thickness, the second initial supplementary thickness, ..., the (n-1)th initial supplementary thickness are all less than the preset thickness.

[0066] In some embodiments, the first initial supplementary thickness is not less than the second initial supplementary thickness, the second initial supplementary thickness is not less than the third initial supplementary thickness, ..., the (n-2)th initial supplementary thickness is not less than the (n-1)th initial supplementary thickness.

[0067] This application also provides a three-dimensional printing method configured to be executed by a three-dimensional printing device, wherein the three-dimensional printing device includes a first material region, a second material region, ..., an Nth material region, where N≥3, and the three-dimensional printing method includes:

[0068] A first material of a predetermined thickness is cured in a first material region to form a first target layer; a second material of a predetermined thickness is cured in a second material region to form a first target layer; ...; and a Nth material of a predetermined thickness is cured in an Nth material region to form a first target layer;

[0069] On a first target layer formed of a first material, a first material of a predetermined thickness is cured to form a second target layer; on a second target layer formed of a second material, a second material of a predetermined thickness is cured to form a second target layer; ...; and on a first target layer formed of an Nth material, a Nth material of a predetermined thickness is cured to form a second target layer;

[0070] ......

[0071] On the s-th target layer formed by the first material, the first material of a predetermined thickness is cured to form the (s+1)-th target layer; on the s-th target layer formed by the second material, the second material of a predetermined thickness is cured to form the (s+1)-th target layer, ..., and on the s-th target layer formed by the N-th material, the N-th material of a predetermined thickness is cured to form the (s+1)-th target layer; where s≥3;

[0072] There is a horizontal difference between the m-th target layer formed by the M-th material and the m-th target layer formed by the (M-1)-th material, where 1≤M≤N and 1≤m≤s.

[0073] In some embodiments, the horizontal difference is greater than zero and less than a preset thickness.

[0074] This application also provides a 3D printing method configured to be executed by a 3D printing device, wherein the 3D printing device includes a first material region and a second material region, wherein the 3D printing method includes:

[0075] A first material of a predetermined thickness is cured in a first material region to form a first target layer; a second material of a predetermined thickness is cured in a second material region to form the first target layer;

[0076] On a first target layer formed of a first material, a first material of a predetermined thickness is cured to form a second target layer; on a second target layer formed of a second material, a second material of a predetermined thickness is cured to form a second target layer.

[0077] ......

[0078] On the s-th target layer formed by the first material, a first material of a predetermined thickness is cured to form the (s+1)-th target layer;

[0079] There is a horizontal difference between the m-th target layer formed by the first material and the m-th target layer formed by the second material, where 1≤m≤s.

[0080] This application also provides a 3D printing method for manufacturing a target object, the target object comprising a first plurality of layers and a second plurality of layers, the method comprising:

[0081] The first multiple layers of the target object are formed using the target material; and

[0082] A second plurality of layers are formed of the target object using a first material and a second material different from the first material, comprising:

[0083] (a) Curing a first material to form a first portion of a first layer in a second plurality of layers, the first portion of the first layer having a first thickness;

[0084] (b) Curing the second material to form a second portion of the first layer in a second plurality of layers, the second portion of the first layer having a second thickness greater than the first thickness;

[0085] (c) Curing the first material to form a first portion of a second layer of a second plurality of layers on a first portion of the first layer, wherein the total thickness of the first portion composed of the first material is greater than the total thickness of the second portion composed of the second material;

[0086] (d) Curing the second material to form a second portion of a second layer of a second plurality of layers on a second portion of the first layer, wherein the total thickness of the second portion composed of the second material is greater than the total thickness of the first portion composed of the first material;

[0087] (e) Repeat steps (c) and (d) to form a second or more layers of the target object.

[0088] In some embodiments, the target material:

[0089] - Same as the first material, or

[0090] - Same as the second material, or

[0091] -Different from the first material and the second material.

[0092] This application also provides a 3D printing method for manufacturing a target object, the target object comprising multiple target layers (1 to n, n≥3), the 3D printing method comprising:

[0093] (a) Curing a first material to form a first portion of a first layer of a plurality of target layers, the first portion of the first layer having a first thickness;

[0094] (b) Curing the second material to form a second portion of a first layer in a plurality of target layers, the second portion of the first layer having a second thickness greater than the first thickness;

[0095] ...

[0096] (c) Curing the i-th material (i≥3) to form the i-th portion of the first layer of a plurality of target layers, wherein the i-th portion of the first layer has an i-th thickness greater than the (i-1)-th thickness;

[0097] (d) Curing the first material to form a first portion of a second layer of a plurality of target layers on a first portion of the first layer, wherein the total thickness of the first portion composed of the first material is greater than the total thickness of the i-th portion composed of the i-th material;

[0098] (e) Curing the second material to form a second portion of a plurality of target layers on a second portion of the first layer, wherein the total thickness of the second portion composed of the second material is greater than the total thickness of the first portion composed of the first material;

[0099] ...

[0100] (f) Curing the i-th material to form the i-th portion of the second layer of a plurality of target layers on the i-th portion of the first layer, wherein the total thickness of the second portion composed of the i-th material is greater than the total thickness of the i-1 portion composed of the (i-1)-th material;

[0101] (g) Repeat steps (d)-(f) to form multiple target layers of the target object;

[0102] Among them, the first material, the second material, ..., the i-th material are all different.

[0103] This application also provides a non-volatile storage medium including a stored program, wherein the program is configured to execute the aforementioned 3D printing method.

[0104] In some embodiments, the first material in the first material region is different from the second material in the second material region. The properties of the first material and the second material may differ; for example, the first material may have a higher viscosity, while the second material may have a lower viscosity.

[0105] In some embodiments, the color of the first material is different from the color of the second material. This allows materials of different colors to be cured in the same slice layer or multiple adjacent slice layers.

[0106] In some embodiments, the first material is a mixture or composite material, or a material comprising multiple materials or a mixture of multiple materials. For example, a printing material composed of at least one of cyan, magenta, yellow, and black (CMYK). For example, the first material comprises cyan and yellow materials. For example, the first material comprises a mixture of cyan and yellow materials.

[0107] In some embodiments, the first material is an additive. For example, the additive includes at least one of the following: pigment, dye, defoamer, leveling agent, wetting agent, dispersant, matting agent.

[0108] In some embodiments, a first material is applied to a first material region before curing, such that the thickness of the first material is 1-10 times a preset thickness; and / or a second material is applied to a second material region before curing, such that the thickness of the second material is 1-10 times a preset thickness. When the applied material is a liquid or paste, a lower liquid level is beneficial for material curing, and is particularly beneficial for multi-color printing, because the forming platform or printhead will not be immersed too deeply in the material, thereby reducing the possibility of color mixing between multiple colors.

[0109] In some embodiments, the thickness of the first material is 2-4 times the preset thickness.

[0110] In some embodiments, the first portion and the second portion are spaced apart in a plane parallel to the molding surface. The first portion and the second portion may be adjacent or spaced apart during construction. In the same slice layer or two adjacent slice layers, there may be at least one first portion and at least one second portion, for example, three first portions and four second portions. Multiple first portions made of the same material may be cured simultaneously.

[0111] In some embodiments, the first portion surrounds the second portion in a plane parallel to the molding surface. For example, a first material with high surface quality for coloring forms the outer first portion, while a second material with better mechanical properties forms the inner second portion.

[0112] In some embodiments, moving the molding platform from a first material region to a second material region includes: driving the molding platform to rise a first height in a direction away from the first material region; driving the molding platform horizontally above the second material region; and driving the molding platform to descend a second height in a direction closer to the second material region. For example, when the first or second material region has vertically extending sidewalls, the first height is greater than the height of the sidewalls to allow the molding platform to switch smoothly between the first and second material regions. For example, the first height can be 2-20 times the height of the sidewalls. When both the first and second material regions are plate-shaped elements, the first height is greater than a preset thickness to allow the cured portion to separate from the tray (first or second material region).

[0113] In some embodiments, the first material and / or the second material are liquid photocurable materials arranged in a tray of a 3D printing device.

[0114] In some embodiments, the first material and / or the second material are applied to the material region via a nozzle. For example, materials within a predetermined viscosity range are applied via the nozzle. The predetermined viscosity threshold corresponding to the available viscosity printing materials at room temperature (e.g., 10–40°C, preferably 20–30°C, e.g., 25°C) is between 50 centipoise and 500,000 centipoise, preferably between 500 centipoise and 200,000 centipoise, more preferably between 100 and 500 centipoise, and particularly preferably between 200 and 300 centipoise.

[0115] In some embodiments, the 3D printing method further includes moving the molding platform to a cleaning area before moving the molding platform from a first material region to a second material region or from a second material region to a first material region, to clean the 3D object being molded on the molding platform. This cleaning step helps to avoid mixing between the first and second materials.

[0116] In some embodiments, the 3D printing method further includes cleaning after forming at least two first parts or at least two second parts. The frequency of cleaning can be controlled, for example, cleaning is performed after curing five slice layers.

[0117] In some embodiments, the 3D printing method further includes: cleaning excess material in the first material region during or after moving the forming platform from the first material region to the second material region; and / or

[0118] During or after moving the molding platform from the second material area to the first material area, clean any excess material in the second material area.

[0119] In some embodiments, the 3D printing method further includes cleaning excess material in the first material region using a scraper.

[0120] In some embodiments, the 3D printing method further includes providing at least a first printing region, a second printing region, and a third printing region, wherein the material applied in the third printing region is the same as or different from at least one of the first and second materials.

[0121] This application also provides a 3D printing method, comprising: curing a first material with at least a first initial supplementary thickness in a first material region, and curing a second material with a preset thickness in a second material region; after curing the second material with the preset thickness, curing a first material with a preset thickness in the first material region, wherein the first initial supplementary thickness is less than the preset thickness. The statement "curing at least a first initial supplementary thickness of the first material" refers to: a) curing only the material with the first initial supplementary thickness; or b) curing a first material with a thickness greater than the first initial supplementary thickness. For example, when the first initial supplementary thickness is 20 μm, the slice thickness is 50 μm, and the preset thickness is 100 μm, a 20 μm first material can be cured first in the first material region, or a 70 μm (20 μm + 50 μm) first material can be cured first in the first material region, or a 120 μm (20 μm + 50 μm + 50 μm) first material can be cured first in the first material region; then a step-curing step is performed, for example, curing a second material with a preset thickness (100 μm) in the second material region.

[0122] In some embodiments, a first region is defined by a container for containing a first material, a second region is defined by a container for containing a second material, and wherein the containers have at least a partially transparent bottom.

[0123] In some embodiments, a first region is defined by a plate-like element for carrying a first material, a second region is defined by a plate-like element for carrying a second material, and wherein the plate-like element has a bottom that is at least partially transparent.

[0124] In some embodiments, the first material is applied via a nozzle to a plate-like element used to carry the first material, and / or

[0125] The second material is applied to the plate-shaped element that carries the second material through a nozzle.

[0126] In some embodiments, the above-described 3D printing method further includes providing at least a third region, wherein the material applied in the third region is the same as or different from at least one of the first material and the second material.

[0127] In some embodiments, the second portion of the second plurality of layers has a uniform layer thickness.

[0128] In some embodiments, a second portion of the second plurality of layers at least partially surrounds a first portion of the second plurality of layers. Attached Figure Description

[0129] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this application and therefore should not be regarded as a limitation on the scope of protection.

[0130] Figure 1 illustrates a 3D printing apparatus according to some embodiments of this application;

[0131] Figures 2A-2F illustrate the printing process according to some embodiments of this application;

[0132] Figure 3 shows a printed object according to some embodiments of this application;

[0133] Figure 4 illustrates a printed object according to some other embodiments of this application;

[0134] Figure 5 shows a printed object according to some embodiments of this application;

[0135] Figures 6A-6C illustrate printed objects according to some embodiments of this application;

[0136] Figures 7A-7B show different height sections of the printed object according to Figures 6A-6C;

[0137] Figures 8A-8H illustrate an exemplary printing process for the second height segment of the printed object of Figures 6A-6C;

[0138] Figures 9A-9I illustrate another exemplary printing process for the second height segment of the printed object in Figures 6A-6C;

[0139] Figure 10 shows the first and second height segments of the printed object according to Figures 6A-6C;

[0140] Figures 11A-11G illustrate an exemplary printing process for the third height segment of the printed object in Figures 6A-6C;

[0141] Figures 12A-12H illustrate an exemplary printing process for the third height segment of the printed object in Figures 6A-6C;

[0142] Figure 13 illustrates an embodiment for forming a target object comprising three different materials;

[0143] Figures 14A-14F illustrate an exemplary printing process for photopolymer additive manufacturing using two different materials; and

[0144] Figures 15A-15G illustrate another exemplary printing process for photopolymer additive manufacturing using two different materials.

[0145] In the accompanying drawings, some of the same or similar reference numerals represent some of the same or similar elements or components, and the scale of each part in the drawings is not necessarily true, but rather schematic. Detailed Implementation

[0146] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0147] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to refer to similar or identical objects and are not necessarily used to describe a specific order or priority, unless otherwise indicated. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, or system, product, or apparatus comprising a series of steps is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0148] Figure 1 illustrates a 3D printing apparatus according to some embodiments of this application. As shown in Figure 1, the 3D printing apparatus 100 includes a radiation device 111, a forming platform (also called a build platform) 112, and a carrier device 113. The radiation device (or optical unit) 111 is used to project light onto the carrier device 113 to cure the printing material located in the carrier device 113. The forming platform 112 has a forming surface, and the printing material between the forming surface of the forming platform 112 and the carrier device 113 is cured by light (e.g., UV light). The radiation device 111 can emit ultraviolet light of a predetermined wavelength (e.g., 385 nm or 405 nm), which penetrates at least a partially transparent bottom of the carrier device 113 and cures the printing material (e.g., photosensitive resin) carried by the carrier device 113. The carrier device 113 is provided with a film, for example, a film with a light transmittance of 80% to 90%. The 3D printing apparatus shown in Figure 1 allows the manufacture of objects using only a single printing material.

[0149] Figure 2A shows a 3D printing device 200 or additive manufacturing system 200, on which a section 240 of an object is adhered. This section 240 is formed using a single material based on multiple slice layers. For simplicity, the support and radiating devices of the 3D printing device are omitted in Figure 2A. Similar to that shown in Figure 1, the support is arranged between the radiating device and the forming platform.

[0150] As shown in Figures 2B-2F, after section 240 is printed, section 240 of the object is adhered to the forming platform or building platform 210. This section 240 is made of material A. Section 250 of the object is then formed using material B, and section 260 of the object is formed using material C.

[0151] Materials A, B, and C are different materials. For example, they differ in their optical properties, such as their ability to absorb light and their light transmittance. They also differ in their physical properties, such as their color, elasticity, and yield strength. Finally, they differ in their chemical properties, such as having different compositions.

[0152] In some embodiments, the material used to form segment 240 is the same as the material used to form segment 250 or segment 260. The object is, for example, a tooth model, including white teeth and red gums. The object is, for example, an architectural model, including architectural segments of various colors. The object is, for example, a figurine model, including segments of various colors or materials.

[0153] In some embodiments, referring to FIG2B, after section 240 is printed using material A, at least one of a molding platform 210 or a carrier device, such as a molding platform or build platform 210, is driven by a drive mechanism (not shown) via an additive manufacturing system to move to the area of ​​the carrier device carrying material B, so that the molding platform 210 is aligned with the area of ​​the carrier material B. Material B is then irradiated and cured, allowing the material B carried by the carrier device to be cured and adhered to section 240 on the molding platform 210 to form layer 251 of section 250, layer 251 having a thickness t1. The cured layer 251 of section 250 is separated from the carrier device, and then the molding platform or build platform 210 is moved to the area of ​​the carrier device carrying material C, so that the molding platform 210 is aligned with the area of ​​the carrier material C. Material C is then irradiated and cured, allowing the material C carried by the carrier device to be cured and adhered to section 240 on the molding platform 210 to form layer 261 of section 260, layer 261 having a thickness t2, t2 > t1.

[0154] In some embodiments, thickness t1 is 1% to 99% of thickness t2, for example, 30% to 70%, or 40% to 60%. In some embodiments, thickness t1 is 50% of thickness t2. In some embodiments, thickness t2 is 5 to 300 μm, preferably 20 to 200 μm, more preferably 50 to 150 μm, and even more preferably 60 to 120 μm. For example, 10 to 280 μm, or 15 to 250 μm, or 25 to 180 μm.

[0155] In some embodiments, if the thickness of t1 is 25 μm and the thickness of t2 is 50 μm, then the overlap length between layer 251 and layer 261 is 25 μm along the vertical direction, the Z-axis direction, or the construction direction of the object. In some embodiments, the thickness of t1 is 30 μm and the thickness of t2 is 60 μm. In some embodiments, the thickness of t1 is 50 μm and the thickness of t2 is 75 μm. In some embodiments, the thickness of t1 is 50 μm and the thickness of t2 is 100 μm. In some embodiments, the thickness of t1 is 75 μm and the thickness of t2 is 150 μm.

[0156] Referring to Figure 2D, after layer 261 of segment 260 has cured, layer 261 of segment 260 and the support device are separated. Then, the molding platform with the adhered object is moved to the area of ​​the support device that holds material B, and material B is radiation cured to form layer 252 on layer 251 of segment 250. The total thickness t3 of the layer composed of material B is greater than the total thickness t2 of the layer composed of material C, i.e., t3 > t2. In some embodiments, the total thickness of the layer composed of material B is equal to the sum of thickness t1 and thickness t2, i.e., t3 = t2 + t1.

[0157] Separate the second layer 252 of the cured segment 250 from the support device, and then move the molding platform or building platform 210 to the area where the support device holds material C. Referring to FIG2E, radiation cure material C to form a second layer 262 on the first layer 261 of segment 260, wherein the total thickness t4 of the layer composed of material C is greater than the total thickness t3 of the layer composed of material B, i.e., t4 > t3. In some embodiments, the total thickness of the layer composed of material C is twice the thickness t2, i.e., t4 = t2 + t2. Repeat the above printing steps to finally form an object, as shown in FIG2F.

[0158] Referring to Figures 2A-2F, multiple layers of object segment 240 can be formed first, and then multiple layers of object segment 250 and segment 260 can be formed by interleaving them.

[0159] Referring to Figures 2A-2F, layer 252 of segment 250 is formed on layer 251 of segment 250, and layers 251 and 252 are spaced apart from layer 261 of segment 260.

[0160] Figure 3 shows a 3D printing apparatus 300, on which a segment 340 of the target object is adhered. This first segment is formed of material A. Segments 350 and 360 are formed on segment 340 along the vertical direction, the Z-axis direction, or the construction direction of the target object, where segment 350 is made of material B and segment 360 is made of a different material C. Segment 370 is formed on segments 350 and 360 along the vertical direction, the Z-axis direction, or the construction direction of the target object, where segment 370 is made of material A. Figure 3 illustrates the construction of an object first using a single material, then using two materials, and finally using a single material.

[0161] Figure 4 shows a schematic diagram of an object formed according to some embodiments. As shown in Figure 4, an additive manufacturing system 400 is used to manufacture an object comprising a segment 440 made of material A and segments 450 and 460 (segments 450 and 460 are of equal height) adhered to the segment 440. Segment 450 comprises multiple layers 451, 452, ..., 455, 456 made of material B. Segment 460 comprises multiple layers 461, 462, ... made of material C. The first layer 451 of segment 450 has a thickness of 50 μm, the last layer 456 of segment 450 has a thickness of 50 μm, and the intermediate layers 452, ..., 455 of segment 450 have a thickness of 100 μm. All layers 461, 462, ... of segment 460 have a thickness of 100 μm. When forming segments 450 and 460, the following sequence is followed: forming the first layer 451 of segment 450; forming the first layer 461 of segment 460; forming the second layer 452 of segment 450; forming the second layer 462 of segment 460; ...; forming the penultimate layer 455 of segment 450; forming the last layer of segment 460; forming the last layer 456 of segment 450. This results in segment 450 having a non-uniform layer thickness overall, while segment 460 has a uniform layer thickness overall.

[0162] When segment 450 of the object is easily noticeable, the surface of segment 450 has a clear boundary line due to the change in layer thickness (from 50 μm to 100 μm), while the surface of segment 460 does not have a clear boundary line due to the change in layer thickness (always 100 μm). When the layer thickness of segment 440 composed of material A is 100 μm, the surface of segment 450 has a clear boundary line due to the change in layer thickness (from 100 μm to 50 μm, and from 50 μm to 100 μm), while the surface of segment 460 does not have a clear boundary line due to the change in layer thickness (always 100 μm).

[0163] Figure 5 illustrates a schematic diagram of an object formed according to some embodiments. As shown in Figure 5, an additive manufacturing system 500 is used to manufacture an object comprising a segment 540 made of material A and segments 550 and 560 adhered to the segment 540 (segments 550 and 560 are of equal height, and segment 560 is at least partially surrounded by segment 550). Segment 550 comprises multiple layers 551, 552, ... made of material B. Segment 560 comprises multiple layers 561, 562, ..., 565, 566 made of material C. The first layer 561 of segment 560 has a thickness of 50 μm, the last layer of segment 560 has a thickness of 50 μm, and the intermediate layers of segment 560 (e.g., layers 562, 565) have a thickness of 100 μm. All layers 551, 552, ... of segment 550 have a thickness of 100 μm. When forming segments 550 and 560, the following sequence is followed: forming the first layer 561 of segment 560; forming the first layer 551 of segment 550; forming the second layer 562 of segment 560; forming the second layer 552 of segment 550; ...; forming the penultimate layer 565 of segment 560; forming the last layer of segment 550; forming the last layer 566 of segment 560. Segment 560 has a non-uniform layer thickness, while segment 550 has a uniform layer thickness. The surface of segment 560 has a distinct boundary line due to the layer thickness variation (from 50 μm to 100 μm), while the surface of segment 550 does not have a distinct boundary line due to the layer thickness variation (always 100 μm). Because segment 560 is at least partially surrounded by segment 550, the boundary line on segment 560 is obscured by segment 550 and is not easily perceptible to the human eye.

[0164] Figures 6A-6C illustrate a target printed object according to an embodiment. As shown in Figures 6A-6B, the object 600 to be formed includes three parts 620, 640, and 660. The first part 620 is made of a first type of material A, the second part 640 is made of a second type of material B, and the third part 660 is made of a third type of material C.

[0165] In Figure 6C, the target object 600 is further divided into three height segments Z1, Z2, and Z3. For example, when manufacturing the target object 600 using photopolymerization technology, such as DLP, material B is first cured in the first height segment Z1, then materials A, B, and C are cured in the second height segment Z2, and finally materials A and C are cured in the third height segment Z3.

[0166] In the first height segment Z1, the target object 600 comprises only a portion made of material B. In the second height segment Z2, the target object 100 has a portion made of material A, a portion made of material B, and a portion made of material C, wherein the portion made of material B is located between the portions made of material A and material C, and contacts them in the horizontal direction (or perpendicular to the height). In the third height segment Z3, the target object 100 has a portion made of material A and a portion made of material C, and they are spaced apart from each other in the horizontal direction.

[0167] Figure 7A shows a schematic diagram of a slice of the target object in the first height segment Z1. The target object in the first height segment Z1 consists of only a single material B, and a portion 740 of the target object can be obtained by continuously curing to form multiple layers 741.

[0168] A portion 740 of the target object is divided into multiple layers 741, for example, 200 layers. Each layer 741 has the same thickness, for example, 30 μm. Alternatively, the multiple layers 741 may have different thicknesses, for example, some of the multiple layers 741 may be 30 μm thick, while others may be 50 μm thick. Larger thicknesses are beneficial for accelerating the printing speed of the target object, while smaller thicknesses are beneficial for obtaining better surface quality.

[0169] Figure 7B shows a schematic cross-section of the target object in the second height segment. The target object in the second height segment Z2 includes a first segment made of material A, a second segment made of material B, and a third segment made of material C. To manufacture the target object in the second height segment (which is formed on the portion of the target object in the first height segment), the target object is layered to facilitate subsequent manufacturing.

[0170] Figure 8A shows a schematic diagram of a portion of an additive manufacturing system. The additive manufacturing system 800 or 3D printing apparatus 800 includes a forming platform 810 for adhering a target object. Figure 8A shows a portion 840 of the target object (made of material B) that has been cured and adhered to the forming platform 810. In the embodiment shown in Figure 8A, a plurality of supports 848, also made of material B, are formed to support this portion 840. In other embodiments, the supports 848 are made of a material different from material B. The additive manufacturing system 800 also includes a carrier device 884 for carrying or containing material B and an optical unit or radiation device 850 for projecting light onto the carrier device 884. For example, the optical unit 850 emits ultraviolet light of a predetermined wavelength (e.g., 385 nm or 405 nm) that penetrates at least a partially transparent bottom of the carrier device 884, causing the printing material B (e.g., photosensitive resin) carried by the carrier device 884 to cure. The carrier device 884 is provided with a film, for example, a film with a light transmittance of 80% to 90%. In Figure 8A, the solidified target object 840 leaves the support device 884 containing material B.

[0171] Figure 8B shows a schematic diagram of a portion of an additive manufacturing system. For simplicity, optical units and some support devices are omitted. A portion 840 of a cured target object, made of material B, is adhered to a forming platform 810 of the additive manufacturing system. The additive manufacturing system drives at least one of the forming platform 810 or the support device 886 via a drive mechanism (not shown) to align the forming platform 810 with the support device 886, thereby allowing the material C carried by the support device 886 to be cured. Figure 8B shows a first portion 861 made of material C adhered to the portion 840 of the target object.

[0172] Figure 8C shows a schematic diagram of a portion of an additive manufacturing system. A molding platform 810 of the additive manufacturing system has portions 840, 861 of a cured target object adhered to it. The additive manufacturing system drives at least one of the molding platform 810 or the carrier device 884 via a drive mechanism (not shown) to align the molding platform 810 with the carrier device 884, thereby allowing material B carried by the carrier device 884 to be cured. Figure 8C shows a second portion 841 composed of material B, which is adhered to a portion 840 of the target object and in contact with a first portion 861 composed of material C. In the embodiment shown in Figure 8C, the first portion 861 and the second portion 841 have the same thickness and the same top or bottom surface; therefore, the first portion 861 and the second portion 841 can be interpreted as two portions of the same layer of the target object. Those skilled in the art will understand that the first portion 861 and the second portion 841 are both formed based on patterned surface exposure. Therefore, the first portion 561 and the second portion 541 of the constructed solid layer 801 can be understood as having a top surface and a bottom surface with equal areas, and having side surfaces extending perpendicular to the top surface and the bottom surface.

[0173] Figure 8D shows a schematic diagram of a portion of an additive manufacturing system. A molding platform 810 of the additive manufacturing system has several portions 840, 861, and 841 of a pre-cured target object adhered to it. The additive manufacturing system drives at least one of the molding platform 810 or the carrier device 882 via a drive mechanism (not shown) to align the molding platform 810 with the carrier device 882, thereby allowing material A carried by the carrier device 882 to be cured. Figure 8D shows a third portion 821 made of material A, which is adhered to a portion 840 of the target object and contacts the first portion 841 made of material B. In the embodiment shown in Figure 8D, the first portion 861, the second portion 841, and the third portion 821 have the same thickness and the same top or bottom surface. In other words, the first portion 861, the second portion 841, and the third portion 821 completely overlap along the build direction of the target object, or the Z-axis direction, or the vertical direction. Therefore, the first part 861, the second part 841 and the third part 821 can be interpreted as three parts of a single layer 801 of the target object.

[0174] Figures 8E-8G illustrate some states for manufacturing the target object. The target object includes a second layer 802 adhered to a first layer 801, the second layer 802 comprising a first portion 862 made of material C (preferably as shown in Figure 8E), a second portion 842 made of material B (preferably as shown in Figure 8F), and a third portion 822 made of material A (preferably as shown in Figure 8G).

[0175] Figures 8E-8G illustrate three states cured in a specified order. Specifically, material C is first cured to form the first part 862, then material B is cured to form the second part 842, and finally material A is cured to form the third part 842. In other embodiments, these three parts are formed in a different order. For example, material C is first cured to form the first part 862, then material A is cured to form the third part 842, and finally material B is cured to form the second part 842. The order in which these three parts are formed in the same layer can be arbitrary.

[0176] Figure 8H shows the second height segment of the formed target object. In Figure 8H, the second height segment Z2 includes multiple layers 801, 802, 803, ..., 808, each layer comprising three parts made of three different materials. For example, the last layer 808 includes a first part 868 made of material C, a second part 848 made of material B, and a third part 828 made of material A.

[0177] The embodiments shown in Figures 8A-8H demonstrate the manufacture of objects having different portions composed of different materials within the same layer. It is understood that the multiple layers of the second height segment Z2 may have the same or different thicknesses. For example, the first layer 801 has a thickness of 50 μm, the second layer 802 has a thickness of 50 μm, and the third layer 803 has a thickness of 60 μm. The thickness of each layer in the second height segment can be, for example, 20 μm–300 μm, 30 μm–200 μm, 40 μm–150 μm, 50 μm–100 μm, 60 μm, 70 μm, 80 μm, 80 μm, 82 μm, 83 μm, 85 μm, or 90 μm.

[0178] To manufacture a second height segment of the target object, this disclosure also provides an alternative. Figure 9A shows a schematic diagram of a portion of an additive manufacturing system. For simplification, optical units and some support devices are omitted. A portion 940 of the target object, made of material B, is adhered to a forming platform 910 of the additive manufacturing system 900. The additive manufacturing system drives at least one of the forming platform 910 or the support device 986 via a drive mechanism (not shown) to align the forming platform 910 with the support device 986, thereby allowing the material C carried by the support device 986 to be cured. Figure 9A shows a first portion 961 made of material C, which is adhered to the portion 940 of the target object and has a thickness t1.

[0179] Figure 9B shows a schematic diagram of a portion of an additive manufacturing system. Parts 940 and 961 of a cured target object are adhered to a molding platform of the additive manufacturing system. The additive manufacturing system drives at least one of the molding platform 910 or the carrier device 984 via a drive mechanism (not shown) to align the molding platform 910 with the carrier device 984. Figure 9B shows a second part 941 made of material B, which is adhered to a part 940 of the target object and in contact with a first part 961 made of material C. The second part 941 has a thickness t2. Specifically, the first part 961 and the second part 941 have top surfaces of the same height (i.e., the surfaces in contact with the cured part 940), but bottom surfaces of different heights opposite to the top surfaces.

[0180] As shown in Figure 9B, the thickness t2 of the second portion 941 is greater than the thickness t1 of the first portion 961. Those skilled in the art will understand that the forming platform of an additive manufacturing system can be driven to move in a vertical direction (or the stacking direction of the slice layers), but errors in the accuracy of the movement are unavoidable. For example, the positioning accuracy of the drive device used to drive the forming platform or carrier device to move in a vertical direction is 25 μm / 300 mm. On the other hand, due to installation errors, the heights of the two carrier devices 984 and 986 may be inconsistent; for example, carrier device 984 may be 25 μm higher than carrier device 986, or carrier device 984 may be 35 μm lower than carrier device 986.

[0181] In one example, material C carried by the support device 986 is cured to form a first portion 961 with a thickness of 50 μm. A forming platform 910 carrying the first portion 961 is raised 300 mm and then moved horizontally (e.g., translated or rotated) from a position aligned with the support device 986 to a position aligned with the support device 984. The forming platform 910 then descends 300 mm to prepare for curing a second portion 941 with a thickness of 50 μm. Due to the positioning accuracy (25 μm / 300 mm) of the drive device used to drive the forming platform vertically, after descent, the forming platform 910 may actually descend 20 μm more than the ideal 300 mm. This would cause the cured first portion 961 to contact the flexible membrane of the support device 984 and move downwards by 20 μm. Such movement scenarios occur repeatedly during the manufacturing of the second height section of the target object, increasing the risk of the cured portion being damaged by the downward pressure on the flexible membrane of the support device. On the other hand, the flexible membrane of the bearing device 984 is repeatedly pressed down by the already cured portion and pulled up when the new cured portion is peeled off, which reduces the membrane's lifespan.

[0182] When the thickness t2 of the second portion 941 is greater than the thickness t1 of the first portion 961, the risk caused by the aforementioned motion error is reduced. For example, the material C carried by the support device 986 is cured to form a first portion 961 with a thickness of 50 μm. The molding platform 910 carrying the first portion 961 is raised by 300 mm and then moved horizontally (e.g., translated or rotated) from a position aligned with the support device 986 to a position aligned with the support device 984. Then, the molding platform 910 descends by 299.9 mm to prepare for curing the second portion 941 with a thickness of 100 μm. Due to the positioning accuracy (25 μm / 300 mm) of the drive device used to drive the molding platform to move in the vertical direction, after descending, the molding platform 910 may actually descend by 20 μm more than the ideal value of 299.9 mm. This will cause the cured first portion 961 to descend by 20 μm more, at which point the first portion 961 is 30 μm away from the flexible film of the support device 984 without contacting the flexible film.

[0183] When the thickness t2 of the second part 941 is greater than the thickness t1 of the first part 961, the risk caused by the aforementioned installation error is reduced. For example, the material C carried by the support device 986 is cured to form a first part 961 with a thickness of 50 μm. The forming platform 910 carrying the first part 961 is raised by 300 mm and then moved horizontally (e.g., translated and / or rotated) from a position aligned with the support device 986 to a position aligned with the support device 984. Then, the forming platform 910 is lowered by 299.9 mm to prepare for curing the second part 941 with a thickness of 100 μm. For example, when the support device 986 is 15 μm lower than the support device 984, and the forming platform 910 is actually lowered by 299.9 mm according to control, the cured first part 961 is 35 μm away from the flexible film of the support device 984, and the cured part 940 is 85 μm away from the flexible film of the support device 984. Neither of them will contact the flexible film.

[0184] Figure 9C shows a schematic diagram of a portion of an additive manufacturing system. Parts 940, 961, and 941 of a cured target object are adhered to a forming platform 910 of the additive manufacturing system. The additive manufacturing system drives at least one of the forming platform 910 or the carrier device 982 via a drive mechanism (not shown) to align the forming platform 910 with the carrier device 982. Figure 9C shows a third part 921 made of material A, which is adhered to a part 940 of the target object and in contact with a second part 941 made of material B. The third part 921 has a thickness t3. Specifically, the first part 961, the second part 941, and the third part 921 have top surfaces of the same height (i.e., the surfaces in contact with the cured part 940), but bottom surfaces of different heights opposite to the top surfaces. The thickness t3 of the third part 921 is greater than the thickness t2 of the second part 941. Along the construction direction of the target object, or the Z-axis direction, or the vertical direction, or the stacking direction of the layers, any two adjacent parts in the first part 961, the second part 941, and the third part 921 partially overlap each other.

[0185] Those skilled in the art will understand that the first part 961, the second part 941 and the third part 921 are all formed based on patterned surface exposure. Therefore, any one of the first part 961, the second part 941 and the third part 921 of the first layer 901 of the target object can be understood as having a top surface and a bottom surface with equal areas, and having a side surface extending perpendicular to the top surface and the bottom surface.

[0186] The first part 961, the second part 941, and the third part 921 can be interpreted as three portions of a layer 901 of the target object. This layer 901 is a layer that includes the solidified product. The first part 961, the second part 941, and the third part 921 of the first layer 901 of the target object have different thicknesses. According to the formation order, the thickness of the later formed portion is greater than the thickness of the earlier formed portion, which can reduce risks, for example, due to the aforementioned positioning accuracy. In other embodiments, curing or printing can be performed in the following order: first, curing material C to form the first part 961 with a thickness t1', then curing material A to form the third part 921 with a thickness t3' (t3' > t1'), and finally curing material B to form the second part 941 with a thickness t2 (t2' > t3').

[0187] Figures 9D-9F illustrate some states used in manufacturing the target object. The target object includes a second layer 902 adhered to a first layer 901. Similar to the first layer, the second layer 902 has three regions of different thicknesses. The second layer 902 includes a first portion 962 made of material C (ideally as shown in Figure 9D), a second portion 942 made of material B (ideally as shown in Figure 9E), and a third portion 922 made of material A (ideally as shown in Figure 9F).

[0188] As shown in Figure 9D, the first portion 962 of the second layer 902 has a thickness t4, such that the total thickness of the first portion composed of material C (i.e., the sum of the first portions 961 of the first layer 901 and 962 of the second layer 902) is greater than the total thickness of the third portion composed of material A. Of course, the total thickness t3 of the third portion 921 composed of material A is greater than the total thickness t2 of the second portion 941 composed of material B. In some embodiments, thickness t4 is equal to thickness t3. In some embodiments, thickness t4 is not equal to thickness t3, but t1 + t4 > t3.

[0189] As shown in Figure 9E, the second portion 942 of the second layer 902 has a thickness t5, such that the total thickness of the second portion composed of material B (i.e., the sum of the second portions 941 of the first layer 901 and 942 of the second layer 902) is greater than the total thickness of the first portion composed of material C (i.e., the sum of the first portions 961 of the first layer 901 and 962 of the second layer 902). In some embodiments, the thickness t5 of the second portion 942 is equal to the thickness t4 of the first portion 962, which is beneficial for the design of process parameters during the slicing process in 3D printing. In some embodiments, the thickness t5 of the second portion 942 is not equal to the predetermined thickness t4 of the first portion 962, but t2+t5>t1+t4.

[0190] As shown in Figure 9F, the third portion 922 of the second layer 902 has a thickness t6, such that the total thickness of the third portion composed of material A (i.e., the sum of the third portion 921 of the first layer 901 and the third portion 922 of the second layer 902) is greater than the total thickness of the second portion composed of material B (i.e., the sum of the second portion 941 of the first layer 901 and the second portion 942 of the second layer 902). In some embodiments, the thickness t6 of the third portion 922 is equal to the predetermined thickness t4 of the first portion 962, which is beneficial for the design of process parameters during the slicing process in 3D printing. In some embodiments, the thickness t6 of the third portion 922 is not equal to the predetermined thickness t4 of the first portion 962, but t3 + t6 > t2 + t5.

[0191] In the embodiments shown in Figures 9A-9F, the thicknesses of these portions of the first and second layers can be configured with various parameters. For example, the thickness t1 of the first portion 961 of the first layer 901 is 1%-90% of the thickness t3 of the third portion 921 of the first layer 901, preferably 30%-70%, more preferably 40%-60%; the thickness t2 (t2 > t1) of the second portion 941 of the first layer 901 is 10%-90% of the thickness t3 of the third portion 921 of the first layer 901, preferably 30%-70%, more preferably 40%-66%.

[0192] As an example, the thickness t1 of the first part 961 of the first layer 901 is one-third of the thickness t3 of the third part 921 of the first layer 901, and the thickness t2 of the second part 941 of the first layer 901 is two-thirds of the thickness t3 of the third part 921 of the first layer 901.

[0193] As an example, the thickness t4 of the first part 962 of the second layer 902 is equal to the thickness t5 of the second part 942 of the second layer 902, and the thickness t5 of the second part 942 of the second layer 902 is equal to the thickness t6 of the third part 922 of the second layer 902. This is beneficial for the design of process parameters in the slicing process in 3D printing.

[0194] As an example, the thickness t4 of the first part 962 of the second layer 902 is equal to the thickness t3 of the third part 921 of the first layer 901, and t4 = t5 = t6, which makes the total thickness (t3 + t6) of the third part composed of material A twice the third thickness (t3).

[0195] Figure 9G illustrates a third layer for manufacturing the second height segment of the target object. The third layer 903 adheres to the second layer 902. Similar to the second layer 902, the third layer 903 has three regions of different thicknesses. The third layer 903 includes a first portion 963 made of material C, a second portion 943 made of material B, and a third portion 923 made of material A. The second height segment Z2 of the target object is defined by an initial axis L1 and an end axis L2. In the embodiment shown in Figure 9G, the third layer 903 has reached the end axis L2, meaning that printing cannot continue in the manner in which the second layer 902 and the third layer 903 are formed because the thickness of the portion to be cured in the second height segment is insufficient. During the formation of the unformed portion in the second height segment, there is a risk that the third portion 623 of the third layer 903 may press down on the film of the bearing device. However, the unformed portion in the second height segment shown in Figure 9G is only a small portion of the second height segment, and this risk is tolerable to those skilled in the art.

[0196] Figures 9H-9I illustrate the end compensation layer for the second height segment of the target object. The end compensation layer, or fourth layer 904, is adhered to the third layer 903. Similar to the third layer 903, the end compensation layer, or fourth layer 904, has two regions of different thicknesses. Specifically, the fourth layer 904 includes a second portion 944 made of material B and a first portion 964 made of material C, the first portion 964 being thicker than the second portion 944.

[0197] Although Figures 9H-9I show the second portion 944 of the fourth layer 904 being formed first, followed by the first portion 964 of the fourth layer 904, in other embodiments, the first portion 964 of the fourth layer 904 may be formed first, followed by the second portion 944 of the fourth layer 904.

[0198] Figures 9A-9I illustrate the steps for manufacturing the second height segment of the target object. Those skilled in the art will understand that, depending on the total thickness of the second height segment of the target object, the target object may have multiple second or third layers. For example, after forming the first layer (or “initial compensation layer”), 100 layers (or “intermediate layers”) are formed consecutively in a manner that forms the second or third layer, and finally, the end compensation layer of the second height segment is formed in a manner that forms the fourth layer.

[0199] The embodiments shown in Figures 9A-9I demonstrate the manufacture of objects having different portions composed of different materials within the same layer. It is understood that the multiple intermediate layers of the second height segment Z2 may have the same or different thicknesses. For example, each portion 962, 942, 922 of the second layer (i.e., the first of the multiple intermediate layers) 902 has a thickness of 50 μm, and each portion 963, 943, 923 of the third layer (i.e., the second of the multiple intermediate layers) 903 has a thickness of either 70 μm or 50 μm.

[0200] The formation of each portion of each layer in the second height segment of the target object is associated with the corresponding slicing parameters. The slicing of the target object may include an initial slicing layer, multiple intermediate slicing layers, and an end slicing layer. For example, a 3D object data model has 500 slice layers, each slice layer being 50 μm thick. An alternating curing strategy can be used from layer 100 to layer 300. For instance, first, a 50 μm thick material C is cured to form the first part of the first layer of the second height segment; then, a 100 μm thick material B (i.e., twice the slice layer thickness) is cured to form the second part of the first layer of the second height segment; next, a 150 μm thick material A (i.e., three times the slice layer thickness) is cured to form the third part of the first layer of the second height segment; then, a 150 μm thick material C (i.e., three times the slice layer thickness) is cured to form the first part of the second layer of the second height segment; then, a 150 μm thick material B is cured to form the second part of the second layer of the second height segment; then, a 150 μm thick material A is cured to form the third part of the second layer of the second height segment; ...; the steps shown in Figures 9A-9I are executed continuously until the end compensation layer of the second height segment is formed.

[0201] The initial slice layer of the target object can be used to form the initial compensation layer of the second height segment, the intermediate slice layer of the target object can be used to form the intermediate layer of the second height segment, and the final slice layer of the target object can be used to form the final compensation layer of the second height segment. The thickness of the target object slice can be designed, for example, 2μm to 200μm, 5μm to 150μm, 10μm to 100μm, 20μm to 80μm, 25μm to 75μm, 30μm to 60μm, 40μm, or 50μm.

[0202] Figure 10 illustrates one printing state of the target object. The first portion 1020 and the third portion 1060 of the target object have not yet been solidified, while the second portion 1040 of the target object has been printed, for example, as shown in Figures 8A-8H or 9A-9I. The third height segment Z3 of the target object involves the third portion 1060 made of material C and the first portion 1020 made of material A. Similarly, the third portion 1060 and the first portion 1020 in the third height segment Z3 of the target object are divided into multiple slice layers with the same or different slice thicknesses.

[0203] Figures 11A-11G show schematic diagrams of the third height section of the additive manufacturing system. For simplicity, optical units and some support devices are omitted. As shown in Figure 11A, a portion 1170 of the already cured target object (i.e., the sum of the first and second height sections) is adhered to the forming platform 1110 of the additive manufacturing system. The additive manufacturing system drives at least one of the forming platform 1110 or the support device 1186 via a drive mechanism (not shown) to align the forming platform 1110 with the support device 1186, thereby allowing the material C carried by the support device 1186 to be cured. Figure 11A shows a first portion 1161 composed of material C, which is adhered to the cured portion 1170 of the target object.

[0204] Figure 11B shows a schematic diagram of a portion of an additive manufacturing system. A portion 1170 of a cured target object is adhered to a molding platform 1110 of the additive manufacturing system. The additive manufacturing system drives at least one of the molding platform 1110 or the carrier device 1182 via a drive mechanism (not shown) to align the molding platform 1110 with the carrier device 1182. Figure 11B shows a second portion 1121 made of material A, which is adhered to the portion 1170 of the target object and spaced apart from a first portion 1161 made of material C. In the embodiment shown in Figure 11B, the first portion 1161 and the second portion 1121 have the same thickness and the same top or bottom surface; therefore, the first portion 1161 and the second portion 1121 can be interpreted as two parts of a layer 1101 of the target object.

[0205] Figure 11C shows a schematic diagram of a portion of an additive manufacturing system. Parts 1170, 1161, and 1121 of a pre-cured target object are adhered to a molding platform 1110 of the additive manufacturing system. The additive manufacturing system aligns the molding platform 1110 with a carrier device 1182, thereby allowing material A carried by the carrier device 1182 to be cured. Figure 11C shows a second portion 1122 made of material A, which is adhered to the second portion 1121 of material A in the first layer 1101 and spaced apart from the first portion 1161 made of material C.

[0206] Figure 11D shows a schematic diagram of a portion of an additive manufacturing system. A molding platform 1110 of the additive manufacturing system has portions 1170, 1161, 1121, and 1122 of a solidified target object adhered to it. The additive manufacturing system drives at least one of the molding platform 1110 or the carrier device 1186 via a drive mechanism (not shown) to align the molding platform 1110 with the carrier device 1186, thereby allowing the material C carried by the carrier device 1186 to solidify. Figure 11D shows a second portion 1162 composed of material C, which is adhered to a second portion 1161 composed of material C from the first layer 1101 and spaced apart from the first portion 1122 composed of material A. In the embodiment shown in Figure 11D, the first portion 1162 and the second portion 1122 have the same thickness and the same top or bottom surface; therefore, the first portion 1162 and the second portion 1122 can be interpreted as two portions of a single layer 1102 of the target object.

[0207] Figure 11E shows a schematic diagram of a portion of the additive manufacturing system. The additive manufacturing system continues to align the molding platform 1110 with the carrier 1186, thereby allowing the material C carried by the carrier 1186 to be cured. Figure 11E shows a first portion 1163 made of material C, which is adhered to a first portion 1162 made of material C in the second layer 1102.

[0208] Figure 11F shows a schematic diagram of a portion of an additive manufacturing system. The additive manufacturing system drives at least one of a molding platform 1110 or a carrier device 1182 via a drive mechanism (not shown) to align the molding platform 1110 with the carrier device 1182, thereby allowing material A carried by the carrier device 1182 to be cured and adhered. Figure 11F shows a second portion 1123 composed of material A, which adheres to the second portion 1122 of the second layer 1102 composed of material A and is spaced apart from the first portion 1162 composed of material C. In the embodiment shown in Figure 11F, the first portion 1163 and the second portion 1123 have the same thickness and the same top or bottom surface; therefore, the first portion 1163 and the second portion 1123 can be interpreted as two parts of a single layer 1103 of the target object.

[0209] Figure 11G shows the third height segment of the formed target object. In Figure 11G, the second height segment Z3 includes multiple layers 1101, 1102, 1103, 1104, ..., 1108, each layer comprising two parts made of two different materials. For example, the last layer 1108 includes a first part 1168 made of material C and a second part 1128 made of material A.

[0210] The embodiments shown in Figures 11A-11G demonstrate the manufacture of objects having different portions composed of different materials within the same layer. It is understood that the multiple layers of the third height segment Z3 may have the same or different thicknesses. For example, the thickness of the first layer 1101 is 50 μm, the thickness of the second layer 1102 is 50 μm, and the thickness of the third layer 1103 is 60 μm. The thickness of each layer in the third height segment can be, for example, 20 μm–300 μm, 30 μm–200 μm, 40 μm–150 μm, 50 μm–100 μm, 60 μm, 70 μm, 80 μm, 80 μm, 82 μm, 83 μm, 85 μm, or 90 μm.

[0211] To manufacture the third height segment of the target object, this disclosure also provides an alternative. Figure 12A shows a schematic diagram of a portion of an additive manufacturing system. For simplification, optical units and some support devices are omitted. A portion 1270 of the target object, which has already been cured, is adhered to a molding platform 1210 of the additive manufacturing system. The additive manufacturing system drives at least one of the molding platform 1210 or the support device 1286 via a drive mechanism (not shown) to align the molding platform 1210 with the support device 1286, thereby allowing the material C carried by the support device 1286 to be cured and adhered. Figure 12A shows a first portion 1261 composed of material C, which is adhered to the portion 1270 of the target object and has a degree t1.

[0212] Figure 12B shows a schematic diagram of a portion of an additive manufacturing system. The additive manufacturing system drives at least one of a molding platform 1210 or a carrier device 1282 via a drive mechanism (not shown) to align the molding platform 1210 with the carrier device 1282, thereby allowing material A carried by the carrier device 1282 to be cured and adhered. Figure 12B shows a second portion 1221 made of material A, which is adhered to a portion 1270 of a target object. The second portion 1221 has a thickness t2. Specifically, the first portion 1261 and the second portion 1221 have top surfaces of the same height (i.e., the surfaces in contact with the cured portion 1270), but bottom surfaces of different heights opposite to the top surfaces.

[0213] As shown in Figure 12B, the thickness t2 of the second part 1221 is greater than the thickness t1 of the first part 1261.

[0214] Those skilled in the art will understand that the first part 1261 and the second part 1221 are both formed based on patterned surface exposure. Therefore, the first part 1261 or the second part 1221 of the first layer 1201 of the target object can be understood as having a top surface and a bottom surface with equal areas, and having a side surface extending perpendicular to the top surface and the bottom surface.

[0215] The first part 1261 and the second part 1221 can be interpreted as two portions of a layer 1201 of the target object. This layer 1201 is a solidified layer. The first part 1261 and the second part 1221 of the first layer 1201 of the target object have different thicknesses. According to the formation order, the thickness of the later formed part is greater than the thickness of the earlier formed part, which can reduce various risks, such as those caused by positioning accuracy due to vertical movement.

[0216] Figures 12C-12D illustrate some states used in manufacturing the target object. The target object includes a second layer 1202 adhered to the first layer 1201. Similar to the first layer, the second layer 1202 has two regions of different thicknesses. The second layer 1202 includes a first portion 1262 made of material C (ideally as shown in Figure 9C) and a second portion 1222 made of material A (ideally as shown in Figure 9D). The first portion 1262 and the second portion 1222 of the second layer 1202 have top surfaces of different heights and bottom surfaces of different heights.

[0217] As shown in Figure 12C, the second portion 1262 of the second layer 1202 has a thickness t3, such that the total thickness of the first portion composed of material C (i.e., the sum of the first portion 1261 of the first layer 1201 and the first portion 1262 of the second layer 1202) is greater than the total thickness of the first portion composed of material C (i.e., the second portion 1262 of the first layer 1201). In some embodiments, thickness t3 is equal to thickness t2. In some embodiments, thickness t3 is not equal to thickness t2, but t1 + t3 > t2.

[0218] As shown in Figure 12D, the second portion 1222 of the second layer 1202 has a thickness t4, such that the total thickness of the second portion composed of material A (i.e., the sum of the second portion 1221 of the first layer 1201 and the second portion 1222 of the second layer 1202) is greater than the total thickness of the first portion composed of material C (i.e., the sum of the first portion 1261 of the first layer 1201 and the second portion 1262 of the first layer 1201). In some embodiments, the thickness t4 is equal to the thickness t3, which is beneficial for the design of process parameters during the slicing process in 3D printing. In some embodiments, the thickness t4 is not equal to the thickness t3, but t2+t4>t1+t3.

[0219] In the embodiments shown in Figures 12A-12D, the thicknesses of these portions of the first and second layers can be configured with a variety of parameters. For example, the thickness t1 of the first portion 1261 of the first layer 1201 is 1% to 90% of the thickness t2 of the second portion 1221 of the first layer 1201, preferably 30% to 70%, more preferably 40% to 60%, for example 50%.

[0220] As an example, the thickness t3 of the first part 1262 of the second layer 1202 is equal to the thickness t4 of the second part 1222 of the second layer 1202, which is beneficial for the design of process parameters in the slicing process during 3D printing. As an example, t2 = t3 = t4, which is also beneficial for the design of process parameters in the slicing process during 3D printing.

[0221] Figures 12E-12F illustrate some state diagrams for manufacturing the target object. The target object includes a third layer 1203 adhered to the second layer 1202. Similar to the second layer, the third layer 1203 has two regions of different thicknesses. The third layer 1203 includes a first portion 1263 made of material C (preferably as shown in Figure 12E) and a second portion 1223 made of material A (preferably as shown in Figure 12F). The first portion 1263 and the second portion 1223 of the third layer 1203 have top surfaces of different heights and bottom surfaces of different heights. In some embodiments, the first portion 1263 and the second portion 1223 of the third layer 1203 have the same thickness, which is beneficial for the design of process parameters during the slicing process.

[0222] As shown in Figure 12C, the second portion 1262 of the second layer 1202 has a thickness t3, such that the total thickness of the first portion composed of material C (i.e., the sum of the first portion 1261 of the first layer 1201 and the first portion 1262 of the second layer 1202) is greater than the total thickness of the first portion composed of material C (i.e., the second portion 1262 of the first layer 1201). In some embodiments, thickness t3 is equal to thickness t2. In some embodiments, thickness t3 is not equal to thickness t2, but t1 + t3 > t2.

[0223] As shown in Figure 12D, the second portion 922 of the second layer 1202 has a thickness t4, such that the total thickness of the second portion composed of material A (i.e., the sum of the second portions 1221 of the first layer 1201 and 1222 of the second layer 1202) is greater than the total thickness of the first portion composed of material C (i.e., the sum of the first portions 1261 and 1262 of the first layer 1201). In some embodiments, thickness t4 is equal to thickness t3, which is beneficial for the design of process parameters during the slicing process in 3D printing. In some embodiments, thickness t4 is not equal to thickness t3, but t2+t4>t1+t3.

[0224] Figure 12G illustrates the second height segment for manufacturing the target object. The third height segment Z3 of the target object is defined by the initial axis L1 and the end axis L2. In the embodiment shown in Figure 12G, the cured target object reaches the end axis L2, meaning that printing cannot continue in the manner of forming the second layer 1202 and the third layer 1203 because the thickness of the portion to be cured in the second height segment is insufficient. During the formation of the unformed portion in the second height segment, there is a risk that the second portion 1224 made of material A may press down on the film of the bearing device. However, the unformed portion in the second height segment shown in Figure 12G is only a small part of the third height segment, and this risk is tolerable to those skilled in the art.

[0225] Figure 12H illustrates the end compensation layer of the third height section used to manufacture the target object. The end compensation layer or fifth layer 1205 includes a first portion 1265 made of material C, the thickness of which is such that the thickness of the first portion made of material C in the third height section is equal to the thickness of the second portion made of material A.

[0226] Figures 12A-12H illustrate the steps for manufacturing the third height section of the target object. Those skilled in the art will understand that, depending on the total thickness of the third height section of the target object, the target object may have multiple second or third layers. For example, after forming the first layer (or “initial compensation layer”), 100 layers (or “intermediate layers”) are continuously formed in a manner that forms the second or third layers, and finally, the end compensation layer of the second height section is formed in a manner that forms the fifth layer.

[0227] The embodiments shown in Figures 12A-12H demonstrate the manufacture of objects having different portions composed of different materials within the same layer. It is understood that the multiple intermediate layers of the third height segment Z3 may have the same or different thicknesses. For example, each portion 1262, 1222 of the second layer (i.e., the first of the multiple intermediate layers) 1202 has a thickness of 50 μm, and each portion 1263, 1223 of the third layer (i.e., the second of the multiple intermediate layers) 1203 has a thickness of, for example, 70 μm or 50 μm.

[0228] After forming the first height segment Z1, the second height segment Z2, and the third height segment Z3, the desired target object is obtained.

[0229] The formation of each portion of each layer in the third height segment of the target object is associated with the corresponding slicing parameters. The slicing of the target object may include an initial slicing layer, multiple intermediate slicing layers, and an end slicing layer. For example, if the data model of a 3D object has 500 slicing layers, each slicing layer being 50 μm thick, an alternating curing strategy can be used from layer 301 to layer 500. For example, first, a 50 μm thick material C is cured to form the first portion of the first layer of the second height segment; then, a 100 μm thick material A (i.e., twice the slicing layer thickness) is cured to form the second portion of the first layer of the second height segment; then, a 100 μm thick material C is cured to form the first portion of the second layer of the second height segment; then, a 100 μm thick material A is cured to form the second portion of the second layer of the second height segment; ...; this process is performed continuously based on the steps shown in Figures 12C-12F until the end compensation layer of the third height segment is formed.

[0230] The initial slice layer of the target object can be used to form the initial compensation layer of the third height segment, the intermediate slice layer of the target object can be used to form the intermediate layer of the second height segment, and the final slice layer of the target object can be used to form the final compensation layer of the second height segment. The thickness of the target object slice can be designed, for example, 2μm to 200μm, 5μm to 150μm, 10μm to 100μm, 20μm to 80μm, 25μm to 75μm, 30μm to 60μm, 40μm, or 50μm.

[0231] Figure 13 illustrates an embodiment for forming a target object comprising three different materials. In the embodiment shown in Figure 13, the additive manufacturing system 1300 includes a support device 1320 for supporting material A, a support device 1340 for supporting material B, and a support device 1360 for supporting material C. The target object includes a single-material portion Bp obtained by continuously curing material B according to the slice layer thickness, and also includes multiple layers involving the three materials A, B, and C. Target layers A1, A2, A3, B1, B2, B3, C1, C2, and C3 have the same thickness (preset thickness). The thickness of supplementary portion A0 is less than the thickness of supplementary portion B0, and the thickness of supplementary portion B0 is less than the preset thickness. In one example, the thickness of supplementary portion A0 is 20 μm, the thickness of supplementary portion B0 is 40 μm, the preset thickness is 60 μm, and the slice layer thickness is 20 μm. In another example, the thickness of supplementary portion A0 is 20 μm, the thickness of supplementary portion B0 is 30 μm, the preset thickness is 50 μm, and the slice thickness is, for example, 10 μm.

[0232] It is understood that there is a horizontal difference between two adjacent target layers composed of different materials (here, "different materials" refers to materials from different material regions, not necessarily materials with different physical and / or chemical properties). The term "horizontal difference" can be interpreted as the height difference between the lower surfaces of the two adjacent target layers, or the height difference between the upper surfaces of the two adjacent target layers, or the height difference between the virtual mid-surfaces of the two adjacent target layers, or similarly.

[0233] In one example, if the thickness of the first supplementary part A0 is set to 20 μm, the thickness of the second supplementary part B0 is 35 μm, and the preset thickness is 60 μm, then: the horizontal difference between the first target layer A1 composed of material A and the first target layer B1 composed of material B is 15 μm; the horizontal difference between the first target layer B1 composed of material B and the first target layer C1 composed of material C is 35 μm.

[0234] In another example, if the thickness of the first supplementary part A0 is set to 20 μm, the thickness of the second supplementary part B0 is 30 μm, and the preset thickness is 50 μm, then: the horizontal difference between the first target layer A1 made of material A and the first target layer B1 made of material B is 10 μm; the horizontal difference between the first target layer B1 made of material B and the first target layer C1 made of material C is 30 μm.

[0235] Taking two printing materials as an example, Figure 14A is a schematic diagram of the initial printing state of the photopolymerization 3D printing method provided according to an optional embodiment of this application. As shown in Figure 14A, there are two types of curing materials on the material tray 1480. Material A is carried in the bearing area 1482, and material B is contained in the bearing area 1484. The forming platform 1410 can move in the vertical direction or in the horizontal direction (preferably as shown by the arrow in Figure 14A).

[0236] The terms "tray" or "carrying device" as used herein can be configured in a variety of ways. In some embodiments, the tray includes multiple boxes in which liquid or paste-like material is contained. In some embodiments, the tray includes multiple plate-like elements on which liquid or paste-like material is applied. In some embodiments, the tray includes at least one box and at least one plate-like element. The forming platform is sized to allow it to fall into the printing area of ​​the respective tray (e.g., box or plate-like element).

[0237] The terms “forming platform” and “tray” used herein should be understood as horizontal. In the event that a forming platform or tray is not horizontal due to manufacturing or layout errors, it also falls within the scope of protection of this application.

[0238] In some embodiments, the material used to form the support is different from any material used to form the body of the target object. For example, the material used to form the support is a water-soluble material, which facilitates the removal of the support. Those skilled in the art will understand that during the curing stage of 3D printing, the support can be considered as part of the target object, serving to support the body of the target object, even though the support is subsequently removed from the body.

[0239] Figure 14A is a schematic diagram of the initial printing state of the photopolymer 3D printing method according to an optional embodiment of this application, wherein the forming platform is located above the material tray. Figure 14B is a schematic diagram of the first state of the photopolymer 3D printing method according to an optional embodiment of this application. As shown in Figure 14B, the forming platform can be moved to the bearing area 1482 first, and then a printed part with a thickness of h1 is cured. It can be understood that the cured part with a thickness of h1 at this time represents the supplementary part. The forming platform can be moved, the material tray can be moved, or both can be moved together to achieve relative movement between the forming platform and the material tray. The bearing device (or material tray) and the forming platform move in the X direction or Y direction (in the horizontal plane of the material tray), and the forming platform also needs to move in the Z direction. The forming platform can rise directly a fixed distance, or it can be a single or multiple compound movements of rising first and then falling, ultimately making the lower surface of the printed part on the forming platform a fixed distance from the bearing area of ​​the bearing device. Figure 14C is a schematic diagram of the second state of the photopolymerization 3D printing method according to an optional embodiment of this application. As shown in Figure 14C, the cured portion of material A with a thickness of h1 is separated from the material tray. Figure 14D is a schematic diagram of the third state of the photopolymerization 3D printing method according to an optional embodiment of this application. As shown in Figure 14D, the forming platform can be controlled to move above the bearing area 1484, and then material B with a thickness of h2 is cured, where h2 is greater than h1. It can be understood that at this time, the distance between the upper surface of the cured portion with a thickness of h2 and the forming surface of the forming platform is 0, and the distance between its lower surface and the forming surface of the forming platform is h2. In other embodiments, if a cured portion with a thickness of n slice layers t has been cured, then the distance between the upper surface of the new cured portion with a thickness of h2 and the forming surface of the forming platform is n*t, and the distance between its lower surface and the forming surface of the forming platform is n*t+h2. When material B is cured, the cured portion of material A is suspended relative to the bearing area, and will not cause compression or damage to the bearing area or the release film in the bearing area. Figure 14E is a schematic diagram of the fourth state of the photopolymerization 3D printing method provided according to an optional embodiment of this application. As shown in Figure 14E, the cured portion of material 2 with a thickness of h2 can be controlled to separate from the material tray.

[0240] Figure 14F is a schematic diagram of the fifth state of the photopolymerization 3D printing method provided according to an optional embodiment of this application. The molding platform can be controlled to move above the support area 1482 and at a distance h4 from the support area 1482, curing material A with a thickness of h3, where h4 = h1 + h3, and h4 > h2, h3 = h2. It is understood that at this time, the distance between the upper surface of the cured portion with a thickness of h3 and the forming surface of the molding platform is h1, and the distance between its lower surface and the forming surface of the molding platform is h4(h1 + h3). In other embodiments, if a cured portion with n slice layers of thickness t has already been cured, then the distance between the upper surface of the new cured portion with a thickness of h3 and the forming surface of the molding platform is n*t + h1, and the distance between its lower surface and the forming surface of the molding platform is n*t + h4. When curing material A with a thickness of h3, the cured portion composed of material B is suspended relative to area A, therefore, it will not cause compression (damage) to the support area (release film).

[0241] Similarly, taking two curing materials as examples, Figure 15A is a schematic diagram of the first state of the photopolymerization 3D printing method provided according to some embodiments of this application. As shown in Figure 15A, the bearing area 1582 carries material M, and the bearing area 1584 carries material N. At this time, the distance between the forming platform and the bearing area 1582 can be controlled to be h1 to cure a layer with a thickness of h1. Figure 15B is a schematic diagram of the second state of the photopolymerization 3D printing method provided according to optional embodiments of this application. As shown in Figure 15B, the position of the forming platform above the bearing area 1582 can be moved up to a position h2 away from the material tray, where h2 is greater than h1 and h2 can be a preset thickness. Then, it is moved horizontally above the bearing area 1584. At this time, the distance between the previously photopolymerized part and the bearing area 1584 is δh1, where δh1 > 0, so it will not cause compression to the bearing area 1584. Figure 15C is a schematic diagram of the third state of the photopolymerization 3D printing method provided according to an optional embodiment of this application. As shown in Figure 15C, the forming platform can be moved so that the distance between it and the material tray is h4, where h4 = h3 + h1, and h3 can be equal to h2 (preset thickness). At this time, the distance between the cured slice portion of material N and the material tray is also h1, which will not cause compression to the bearing area 1582. By repeating the above steps and performing photopolymerization printing according to the printing data, the final target model can be obtained.

[0242] In some embodiments, the difference (absolute value) between h2 and h1 is 1%-99% of the preset thickness, preferably 2%-90%, more preferably 5%-80%, for example 30%, 40%, 50%, 60%, or 70%. For example, if the preset thickness is 50 μm, the difference (absolute value) between h2 and h1 can be 1 μm, 2 μm, 5 μm, 10 μm, 20 μm, 25 μm, 30 μm, 40 μm, 48 μm, or 49 μm.

[0243] In some embodiments, the molding platform is moved from the support region 1582 to the support region 1584. For example, the molding platform is driven to rise a first height in a direction away from the support region 1582; ​​the molding platform is driven to move horizontally above the support region 1584; and the molding platform is driven to descend a second height in a direction closer to the support region 1584. For example, when the support region 1582 or the support region 1584 has vertically extending sidewalls, the first height is greater than the height of the sidewalls to allow the molding platform to switch smoothly between the support regions 1582 and 1584. For example, the first height may be 2 to 20 times the height of the sidewalls. When both the support regions 1582 and 1584 are provided with plate-like elements, the first height is greater than a preset thickness to allow the cured portion to separate from the tray (support region 1582 or support region 1584).

[0244] Figure 15D is a schematic diagram of the fourth state of the photopolymerization 3D printing method provided according to an optional embodiment of this application. As shown in Figure 15D, the dashed line between the support area 1582 and the support area 1584 can be a solid structure of a certain height separating the two support areas, such as a partition 1570. The molding platform can be controlled to move up to a predetermined height (e.g., L1+h1) above the support area 1582, and then move to the top of the support area 1584. At this time, the distance between the support area 1584 and the lower surface of the slice portion corresponding to the photopolymerized material M on the molding platform is L1.

[0245] FIG. 15E is a schematic diagram of the fifth state of the photo-curing 3D printing method provided according to an optional embodiment of the present application. As shown in FIG. 15, the forming platform can be controlled to descend to a position where the distance from the bearing area 1584 is h_layer, and then the corresponding part of material N with a thickness of h_layer is cured. At this time, the descending distance of the forming platform is L2, and after the descent, the distance between the lower surface of the photo-cured slice part corresponding to material M and the bearing area 1584 is δh1. FIG. 15F is a schematic diagram of the sixth state of the photo-curing 3D printing method provided according to an optional embodiment of the present application. As shown in FIG. 15F, the forming platform can be controlled to move upward and then translate above the bearing area 1582. Among them, the distance between the lower surface of the photo-cured slice part corresponding to material N and the bearing area 1582 is L3. FIG. 15G is a schematic diagram of the seventh state of the photo-curing 3D printing method provided according to an optional embodiment of the present application. As shown in FIG. 15G, the forming platform can be controlled to descend by L4. At this time, the height between the photo-cured slice part corresponding to material M on the forming platform and the bearing area can be controlled to be h_layer, and the distance between the lower surface of the slice part corresponding to material N and the bearing area 1582 is δh2. At this time, the slice part corresponding to material M with a thickness of h_layer is photo-cured, that is, the total thickness of the formed material M is h_layer+h1. The above operations can be repeated to obtain multiple cured layers, and finally the target model can be obtained.

[0246] As an example, L1 = 10mm, the material tray and the platform can move relatively, so that the platform faces the bearing area 1584 directly, and then the platform descends by L2 = 9.975mm (10mm - 9.975mm = 25μm). Among them, L1 - L2 = δh1. The forming platform can also perform composite movements such as rising and descending multiple times to achieve the final displacement of δh1. Among them, L1 is any value in [δh1, 100000mm]. Then, material N is exposed in the bearing area 1584 to cure the material. Then, the forming platform can rise by L3, for example, L3 = 10mm, the material tray platform moves relatively, so that the platform faces the bearing area 1582 directly, and then the platform descends by L4 = 9.975mm (10mm - 9.975mm = 25μm). L3 - L4 = δh2, where 0 < δh1 < h_layer, 0 < δh2 < h_layer, and δh1 + δh2 = h_layer.

[0247] It should be noted that all the three-dimensional printing devices or additive manufacturing systems of the embodiments of the present application include a forming platform, a bearing device, and a radiation unit, and the bearing device is arranged between the forming platform and the radiation unit.

[0248] In some embodiments, the 3D printing method provided in some embodiments of this application further includes: alternating curing to form n first parts (i.e., the total thickness of the target cured parts is n*h2) and n second parts (i.e., the total thickness of the target cured parts is n*h3), where n≥2, or alternating curing to form n first parts and n-1 second parts, where n≥2. The final material cured in an alternating manner can be either a first material or a second material.

[0249] In some embodiments, the 3D printing method provided in some embodiments of this application further includes: after forming n first parts (i.e., the total thickness of the target solidified parts is n*h2) and n second parts (i.e., the total thickness of the target solidified parts is n*h3), moving the molding platform to the first material region, and solidifying the first material of a second supplementary thickness to form an end supplementary part. The end supplementary part has a first end supplementary surface close to the molding surface of the molding platform and a second end supplementary surface away from the molding surface, wherein the first end supplementary surface is spaced from the molding surface by a first end supplementary distance, and the second end supplementary surface is spaced from the molding surface by a second end supplementary distance; wherein the first end supplementary surface is flush with the last formed surface of the nth first part, and the second end supplementary surface is flush with the last formed surface of the nth second part. It is understood that this end supplementary part is not necessary, especially when the most recently solidified part is the last slice of the model.

[0250] In some embodiments, the 3D printing method provided in some embodiments of this application further includes: after forming n first parts (i.e., the total thickness of the target solidified parts is n*h2) and n-1 second parts (i.e., the total thickness of the target solidified parts is (n-1)*h3), moving the molding platform to the second material region, and solidifying the second material of the second supplementary thickness to form an end supplementary part. The end supplementary part has a first end supplementary surface close to the molding surface of the molding platform and a second end supplementary surface away from the molding surface, wherein the first end supplementary surface is spaced from the molding surface by a first end supplementary distance, and the second end supplementary surface is spaced from the molding surface by a second end supplementary distance; wherein the first end supplementary surface is flush with the last formed surface of the (n-1)th second part, and the second end supplementary surface is flush with the last formed surface of the nth first part. It is understood that this end supplementary part is not necessary, especially when the latest solidified part is the last slice of the model.

[0251] Understandably, when obtaining slices from a 3D object's data model, slicing can be performed according to actual needs. Slicing can include an initial slice layer, multiple intermediate slice layers, and an end slice layer. For example, if a 3D object's data model has 500 slice layers, each 50 μm thick, conventional layer-by-layer curing can be used for layers 1 to 100, such as curing the first material at a relatively fast speed, with each curing thickness being 50 μm. Then, for layers 101 to 300, the aforementioned non-flush curing or alternating curing can be used, for example, first curing a 50 μm thick second material, then curing a 100 μm thick first material, followed by curing a 100 μm thick second material, then curing a 100 μm thick first material, and so on, to complete the non-flush or alternating curing of layers 101 to 300. Conventional layer-by-layer curing can be used again for layers 301 to 500. The layer thickness of the slices and the preset thickness in the alternating curing can be designed.

[0252] The initial supplementary portion belongs to the initial slice layer or the first slice layer of the 3D object's data model, which means that non-flush curing or alternating curing begins directly. The initial supplementary portion belongs to the intermediate slice layer of the 3D object's data model, which means that non-flush curing or alternating curing begins only after multiple layers have been formed through conventional layer-by-layer curing.

[0253] In some embodiments, the first or second material is cured in a single-cure slice thickness manner before the initial supplementary portion is formed.

[0254] In some embodiments, an end supplement portion is formed when printing is performed on the end slice layer or at least one of a plurality of intermediate slice layers.

[0255] In some embodiments, after the end supplement portion is formed, the first material or the second material is cured in a single-cure slice thickness manner.

[0256] In some embodiments, the first portion and the second portion are spaced apart in a plane parallel to the molding surface. The first portion and the second portion may be adjacent or spaced apart during construction. In the same slice layer or two adjacent slice layers, there may be at least one first portion and at least one second portion, for example, three first portions and four second portions. Multiple first portions made of the same material may be cured simultaneously.

[0257] In some embodiments, the first portion surrounds the second portion in a plane parallel to the molding surface. For example, a first material with high surface quality for coloring forms the outer first portion, while a second material with better mechanical properties forms the inner second portion.

[0258] In some embodiments, the 3D printing method further includes providing at least a first printing region, a second printing region, and a third printing region, wherein the material applied in the third printing region is the same as or different from at least one of the first and second materials.

[0259] This application also provides a 3D printing method, comprising: curing a first material with a first initial supplementary thickness in a first material region, and curing a second material with a preset thickness in a second material region; after curing the second material with the preset thickness, curing the first material with the preset thickness in the first material region, wherein the first initial supplementary thickness is less than the preset thickness. The statement "curing at least the first initial supplementary thickness of the first material" refers to: a) curing only the material with the first initial supplementary thickness; or b) curing a first material with a thickness greater than the first initial supplementary thickness. In one example, when the first initial supplementary thickness is 20 μm, the slice thickness is 50 μm, and the preset thickness is 100 μm, a 20 μm first material can be cured first in the first material region, or a 70 μm (20 μm + 50 μm) first material can be cured first in the first material region, or a 120 μm (20 μm + 50 μm + 50 μm) first material can be cured first in the first material region; then a non-flush curing step is performed, for example, curing the second material with a preset thickness (100 μm) in the second material region. In another example, when the first initial supplemental thickness is 20 μm, the slice thickness is 50 μm, and the preset thickness is 50 μm, the first material of 20 μm can be cured first in the first material region, or the first material of 70 μm (20 μm + 50 μm) can be cured first in the first material region, or the first material of 120 μm (20 μm + 50 μm + 50 μm) can be cured first in the first material region; then a non-flush curing step is performed, for example, curing the second material of the preset thickness (50 μm) in the second material region.

[0260] In some embodiments, non-flush curing or alternating curing can be applied to three different materials. For example, a 3D printing device includes a first material region, a second material region, and a third material region. It can first cure a first initial supplementary thickness of 20 μm in the first material region, then cure a second initial supplementary thickness of 40 μm in the second material region, then cure a preset thickness of 60 μm in the third material region, then cure a preset thickness of 60 μm in the first material region, then cure a preset thickness of 60 μm in the second material region, then cure a preset thickness of 60 μm in the third material region, and so on. The target cured portion is formed in this non-flush curing or alternating curing manner.

[0261] In some embodiments, non-flush curing or alternating curing can be applied to at least four materials. For example, a 3D printing device includes a first material region, a second material region, ..., an nth material region, where n ≥ 4. A first initial supplementary thickness of 20 μm can be cured first in the first material region, then a second initial supplementary thickness of 40 μm can be cured in the second material region, ..., then a predetermined thickness of the nth material region can be cured, then a predetermined thickness of the first material region can be cured, then a predetermined thickness of the second material region can be cured, ..., then a predetermined thickness of the nth material region can be cured... The target cured portion is formed in this non-flush curing or alternating curing manner. It is understood that the specific values ​​can be selected.

[0262] In some embodiments, the first initial supplementary thickness is not less than the second initial supplementary thickness, the second initial supplementary thickness is not less than the third initial supplementary thickness, ..., the (n-2)th initial supplementary thickness is not less than the (n-1)th initial supplementary thickness.

[0263] As an alternative embodiment, multiple curing materials are located in multiple trays or in multiple areas of a single tray.

[0264] Optionally, multiple curing materials can be located in multiple trays or in multiple areas of a single tray. For example, the tray may be a glass and film without edges or intermediate gaps, appearing as a single tray but divided into areas A and B; or it may consist of two trays, A and B.

[0265] As an optional embodiment, multiple curing materials are controlled to be cured sequentially based on the first-layer slice model to obtain slice models other than the first-layer slice model in the multi-layer slice model, including: controlling multiple curing materials to be cured sequentially on the first-layer slice model on the molding platform to obtain multiple slice parts, wherein the thickness of each of the multiple slice parts is a preset thickness; and obtaining slice models other than the first-layer slice model in the multi-layer slice model based on the multiple slice parts.

[0266] Optionally, when solidifying the slice model (excluding the first layer slice model), the thickness of each slice can be controlled to be the same, based on the first layer slice model, and all slices can have a preset thickness, namely h_layer. The value of h_layer can be adjusted according to the actual situation. However, when printing the last layer slice model, the required printing thickness can be adjusted according to the actual situation to form the target model.

[0267] In some embodiments, a first material is applied to a first material region before curing, such that the thickness of the first material is 1-10 times a preset thickness; and / or a second material is applied to a second material region before curing, such that the thickness of the second material is 1-10 times a preset thickness. When the applied material is a liquid or paste, a lower liquid level is beneficial for material curing, and is particularly beneficial for multi-color printing, because the forming platform or printhead will not be immersed too deeply in the material, thereby reducing the possibility of color mixing between multiple colors.

[0268] In some embodiments, the thickness of the first material is 2-4 times the preset thickness.

[0269] As an optional embodiment, the thickness of the various curing materials in their respective trays does not exceed a preset thickness.

[0270] Optionally, the thickness of various curing materials in their respective trays should not exceed a preset thickness. Excessive material thickness in the trays may cause excess material to adhere to the slice model and the forming platform, affecting the final result of the target model. During photopolymer printing, after printing a slice, the resulting slice can be cleaned. The cleaning method can be determined based on the actual situation. For example, the forming platform can be rotated centrifugally to remove residual material from the previous print, or residual material can be dried using air nozzles, or the material can be absorbed by a sponge. Whether cleaning is necessary can also be determined based on the degree of material penetration.

[0271] As an optional embodiment, the above-described 3D printing method further includes: cleaning the target object after curing the first material to form a first portion of a second layer of a second plurality of layers on a first portion of the first layer, and / or

[0272] The target object is cleaned by curing a second material to form a second portion of a second plurality of layers on a second portion of a first layer.

[0273] In some embodiments, the 3D printing method further includes moving the molding platform to a cleaning area before moving the molding platform from a first material region to a second material region or from a second material region to a first material region, to clean the 3D object being molded on the molding platform. This cleaning step helps to avoid mixing between the first and second materials.

[0274] In some embodiments, the 3D printing method further includes cleaning after forming at least two first parts or at least two second parts. The frequency of cleaning can be controlled, for example, cleaning is performed after curing five slice layers.

[0275] In some embodiments, cleaning includes at least one of rotating a forming platform, wiping a three-dimensional object, applying airflow to a three-dimensional object, and surrounding the target object with an adsorbent to remove excess printing material.

[0276] In some embodiments, cleaning includes at least one of a rotational forming platform, wiping the three-dimensional object, applying airflow to the three-dimensional object, and surrounding the three-dimensional object with an absorbent to remove excess printed material. For example, a rotational forming platform is used to shake off material adhering to a cured portion. For example, an absorbent, such as a sponge, is used to contact the cured portion to absorb material thereon.

[0277] In some embodiments, the 3D printing method further includes: cleaning excess material in the first material region during or after moving the molding platform from the first material region to the second material region; and / or, cleaning excess material in the second material region during or after moving the molding platform from the second material region to the first material region.

[0278] In some embodiments, the 3D printing method further includes cleaning excess material in the first material region using a scraper.

[0279] In some embodiments, the first material in the first material region is different from the second material in the second material region. The properties of the first material and the second material may differ; for example, the first material may have a higher viscosity, while the second material may have a lower viscosity.

[0280] In some embodiments, the color of the first material is different from the color of the second material. This allows materials of different colors to be cured in the same slice layer or multiple adjacent slice layers.

[0281] In some embodiments, the first material is a mixture or composite material. Alternatively, it may comprise multiple materials or a mixture of multiple materials. For example, a printing material composed of at least one of cyan, magenta, yellow, and black (CMYK). For example, the first material may include cyan and yellow materials. For example, the first material may include a mixture of cyan and yellow materials.

[0282] In some embodiments, the first material is an additive. For example, the additive includes at least one of the following: pigment, dye, defoamer, leveling agent, wetting agent, dispersant, matting agent.

[0283] In some embodiments, the first material and / or the second material are liquid photocurable materials arranged in a tray of a 3D printing device.

[0284] In some embodiments, the first material and / or the second material are applied to the material region via a nozzle. For example, materials within a predetermined viscosity range are applied via the nozzle. The predetermined viscosity threshold corresponding to the available viscosity printing materials at room temperature (e.g., 10–40°C, preferably 20–30°C, e.g., 25°C) is between 50 centipoise and 500,000 centipoise, preferably between 500 centipoise and 200,000 centipoise, more preferably between 100 and 500 centipoise, and particularly preferably between 200 and 300 centipoise.

[0285] Slicing the 3D data model is beneficial in the pre-processing stage of 3D printing. The 3D data model can be sliced ​​into multiple slices of the same or different thicknesses. For example, a single 3D data model can be sliced ​​into 1000 layers, where the slices from layers 1 to 500 have a layer thickness of 50 μm, and the slices from layers 501 to 1000 have a layer thickness of 150 μm.

[0286] In some embodiments, the design of the slice layer thickness during preprocessing is related to a preset layer thickness in non-flush printing or alternating printing. For example, the slice layer thickness is proportional to the preset layer thickness. For example, the ratio of the slice layer thickness to the preset layer thickness is 0.5, 1, or 2. In an exemplary example, the slice layer thickness is 60 μm, and the preset layer thickness is 30 μm, 60 μm, or 120 μm.

[0287] In some embodiments, the slice layer thickness during preprocessing is designed independently of the preset layer thickness in non-flush printing or alternating printing. In some embodiments, the above-described 3D printing method includes providing at least a third region, wherein the material applied in the third region is the same as or different from at least one of the first and second materials.

Claims

1. A method for manufacturing a target object using an additive manufacturing system, the additive manufacturing system comprising a forming platform, a radiating device, and at least two support devices located between the forming platform and the radiating device, the method comprising: The molding platform is aligned with the first support device of at least two support devices, and then the first material carried by the first support device is cured by a radiation device to form a first portion of a first layer, the first portion of the first layer having a first thickness; Align the molding platform with the second support device of at least two support devices, and then cure the second material carried by the second support device by a radiation device to form a second part of the first layer, the second part of the first layer having a second thickness greater than the first thickness; Align the molding platform with the first support device again, and then solidify the first material to form the first part of the second layer on the first part of the first layer, such that the total thickness of the first part composed of the first material is greater than the total thickness of the second part composed of the second material. Align the molding platform with the second support device again, and then cure the second material to form the second part of the second layer on the second part of the first layer, such that the total thickness of the second part composed of the second material is greater than the total thickness of the first part composed of the first material.

2. The method according to any one of the preceding claims further includes: Multiple stacked layers are formed on the second layer, wherein for each stacked layer, a first part made of a first material and a second part made of a second material are alternately formed.

3. The method according to any one of the preceding claims, wherein, After forming n first parts and n second parts, form the (n+1)th first part so that the total thickness of the (n+1)th first part is equal to the total thickness of the n second parts, where n≥2.

4. The method according to any one of the preceding claims further includes providing a plurality of slice layers of the target object, the plurality of slice layers including an initial slice layer, a plurality of intermediate slice layers and an end slice layer, wherein a first portion of the first layer is formed based on at least one of the initial slice layer or the intermediate slice layer, and the (n+1)th first portion is formed based on at least one of the end slice layer or the intermediate slice layer.

5. The method according to any one of the preceding claims, wherein the total thickness of the first portion of the first layer and the second layer is equal to the sum of the first thickness and the second thickness.

6. The method according to any one of the preceding claims, wherein the total thickness of the second portion of the first layer and the second layer is twice the second thickness.

7. The method according to any one of the preceding claims further comprises: Align the molding platform with the third support device among at least two support devices, and then cure the third material supported by the third support device by a radiation device to form the third part of the first layer, wherein the third part of the first layer has a third thickness greater than the second thickness; Align the molding platform with the third support device again, and then cure the third material to form the third part of the second layer on the third part of the first layer, such that the total thickness of the third part made of the third material is greater than the total thickness of the second part made of the second material.

8. The method according to any one of the preceding claims further comprises: Multiple stacked layers are formed on the second layer, wherein for each stacked layer, a first part made of a first material, a second part made of a second material, and a third part made of a third material are alternately formed.

9. The method according to any one of the preceding claims, wherein, After forming n first parts, n second parts, and n third parts, form the (n+1)th first part and the (n+1)th second part, so that the total thickness of the (n+1)th first part, the total thickness of the (n+1)th second part, and the total thickness of the (n)th third parts are the same, where n≥2.

10. The method according to any one of the preceding claims, wherein the total thickness of the first portion of the first layer and the second layer is equal to the sum of the first thickness and the third thickness.

11. The method according to any one of the preceding claims, wherein the total thickness of the second portion of the first layer and the third layer is twice the thickness of the third layer.

12. The method according to any one of the preceding claims, wherein the first thickness is 1%-99% of the second thickness, for example 30%-70%, for example 40%-60%, for example 50%.

13. The method according to any one of the preceding claims, wherein the second thickness is 5 to 300 μm, for example 20 to 200 μm, for example 50 to 150 μm, for example 60 to 120 μm.

14. The method according to any one of the preceding claims further comprises: At least one target layer of a target object is formed using a target material, wherein multiple target layers are formed before the first layer; or multiple target layers are formed after the second layer.

15. The method according to any one of the preceding claims, wherein the target material: - Same as the first material, or - Same as the second material, or -Different from the first material or the second material.

16. The method according to any one of the preceding claims, wherein a first portion of the second layer is formed on a first portion of the first layer along the construction direction of the target object; and, along a direction perpendicular to the construction direction, the first portion of the first layer is in contact with or spaced apart from the second portion of the first layer.

17. The method according to any one of the preceding claims further comprises: After the first part of the first layer is formed, the target object that has adhered to the forming platform is cleaned. and / or After the second part of the first layer is formed, the target object that has adhered to the molding platform is cleaned.

18. The method according to any one of the preceding claims, wherein the cleaning comprises at least one of a rotary forming platform, wiping a target object, applying an airflow to the target object, or surrounding the target object with an adsorbent.

19. The method according to any one of the preceding claims, wherein at least two support devices further include an additional support device configured to receive a cleaning material or a third material, the cleaning material being the same as the first material or the second material, and the third material being different from the first material or the second material.

20. The method according to any one of the preceding claims, wherein the first carrier is a box, the method further comprising supplying a first material to the box to allow the box to contain a predetermined volume of the first material.

21. The method according to any one of the preceding claims, wherein the first support device is a plate-like element, the method further comprising applying the first material to the first support device via a nozzle.

22. The method according to any one of the preceding claims further comprises: After the first part of the first layer is formed, the first support device is cleaned.

23. The method according to any one of the preceding claims, wherein aligning the molding platform with a first support device of at least two support devices comprises: At least one of a mobile forming platform or a first supporting device.

24. The method according to any one of the preceding claims, wherein the movement comprises at least one of translation or rotation.

25. In the method according to any one of the preceding claims, the thickness of the first material carried by the first bearing device is 2 to 10 times the thickness of the first material.

26. An additive manufacturing system for manufacturing a target object, comprising: Molding platform; Radiation device; The first support device is located between the forming platform and the radiation device, and is configured to support the first material; The second support device is located between the forming platform and the radiation device, and is configured to support a second material that is different from the first material; A drive mechanism configured to align the molding platform with a first or second support device; and The controller is configured as follows: - Align the molding platform with the first support device of at least two support devices, and then cure the first material carried by the first support device by a radiation device to form a first portion of a first layer, the first portion of the first layer having a first thickness; - Align the molding platform with the second support device in at least two support devices, and then cure the second material carried by the second support device by a radiation device to form a second part of the first layer, the second part of the first layer having a second thickness greater than the first thickness; -Align the molding platform with the first support device again, and then solidify the first material to form the first part of the second layer on the first part of the first layer, such that the total thickness of the first part composed of the first material is greater than the total thickness of the second part composed of the second material. - Align the molding platform with the second support device again, and then cure the second material to form the second part of the second layer on the second part of the first layer, such that the total thickness of the second part composed of the second material is greater than the total thickness of the first part composed of the first material.

27. A three-dimensional printing method, characterized in that, include: Align the molding platform with the first material area, and solidify the first material to form a first portion of a predetermined thickness of the target object, wherein the first portion has a first surface close to the molding surface of the molding platform and a second surface away from the molding surface, wherein the first surface is spaced apart from the molding surface by a first distance, and the second surface is spaced apart from the molding surface by a second distance. Align the molding platform with the second material area, and solidify the second material to form a second part of the target object with a preset thickness, wherein the second part has a third surface close to the molding surface of the molding platform and a fourth surface away from the molding surface, wherein the third surface is spaced a third distance from the molding surface and the fourth surface is spaced a fourth distance from the molding surface. The third distance is within the range of the first and second distances.

28. The three-dimensional printing method according to any one of the preceding claims, characterized in that, Also includes: After forming a second part of a preset thickness, the molding platform is aligned with the first material area, and the first material of the preset thickness is cured to form an additional first part on the first part, wherein the additional first part has a fifth side close to the molding surface and a sixth side away from the molding surface. The fifth surface is flush with the second surface, the fifth surface is separated from the forming surface by a distance of five, and the sixth surface is separated from the forming surface by a distance of six. The fourth distance falls within the range of the fifth and sixth distances.

29. The three-dimensional printing method according to any one of the preceding claims, characterized in that, Also includes: Before forming the first part of the preset thickness, the molding platform is aligned with the second material area, and the second material of the first supplementary thickness is solidified to form an initial supplementary part. The initial supplementary part has a first supplementary surface close to the molding surface of the molding platform and a second supplementary surface away from the molding surface, wherein the first supplementary surface is spaced apart from the molding surface by a first supplementary distance, and the second supplementary surface is spaced apart from the molding surface by a second supplementary distance. The first supplementary distance is equal to the first distance, and the second supplementary distance is equal to the third distance.

30. A three-dimensional printing method, characterized in that, Configured to be executed via a 3D printing device, wherein the 3D printing device includes a first material region, a second material region, ..., an nth material region, where n ≥ 3, the 3D printing method includes: A first material of at least a first initial supplementary thickness is cured in a first material region, a second material of at least a second initial supplementary thickness is cured in a second material region, ..., and a material of a preset thickness is cured in an nth material region; After curing the nth material of a preset thickness, the first material, the second material, ..., the (n-1)th material of a preset thickness are cured in the first material region, the second material region, ..., the (n-1)th material region, respectively. The first initial supplementary thickness, the second initial supplementary thickness, ..., the (n-1)th initial supplementary thickness are all less than the preset thickness.

31. The three-dimensional printing method according to claim 30, characterized in that, The first initial supplementary thickness is not less than the second initial supplementary thickness, the second initial supplementary thickness is not less than the third initial supplementary thickness, ..., the (n-2)th initial supplementary thickness is not less than the (n-1)th initial supplementary thickness.

32. A three-dimensional printing method, characterized in that, Configured to be executed via a 3D printing device, wherein the 3D printing device includes a first material region, a second material region, ..., an Nth material region, where N≥3, the 3D printing method includes: A first material of a predetermined thickness is cured in a first material region to form a first target layer; a second material of a predetermined thickness is cured in a second material region to form a first target layer; ...; and a Nth material of a predetermined thickness is cured in an Nth material region to form a first target layer; On a first target layer formed of a first material, a first material of a predetermined thickness is cured to form a second target layer; on a second target layer formed of a second material, a second material of a predetermined thickness is cured to form a second target layer; ...; and on a first target layer formed of an Nth material, a Nth material of a predetermined thickness is cured to form a second target layer; ....... On the s-th target layer formed by the first material, a first material of a predetermined thickness is cured to form the (s+1)-th target layer; on the s-th target layer formed by the second material, a second material of a predetermined thickness is cured to form the (s+1)-th target layer, ..., and on the s-th target layer formed by the N-th material, a material of a predetermined thickness is cured to form the (s+1)-th target layer; where s ≥ 3. There is a horizontal difference between the m-th target layer formed by the M-th material and the m-th target layer formed by the (M-1)-th material, where 1≤M≤N and 1≤m≤s.

33. The three-dimensional printing method according to claim 32, wherein the horizontal difference is greater than zero and less than a preset thickness.

34. A three-dimensional printing method, characterized in that, Configured to be executed via a 3D printing device, wherein the 3D printing device includes a first material region and a second material region, wherein the 3D printing method includes: A first material of a predetermined thickness is cured in a first material region to form a first target layer; a second material of a predetermined thickness is cured in a second material region to form the first target layer; On a first target layer formed of a first material, a first material of a predetermined thickness is cured to form a second target layer; on a second target layer formed of a second material, a second material of a predetermined thickness is cured to form a second target layer. ....... On the s-th target layer formed by the first material, a first material of a predetermined thickness is cured to form the (s+1)-th target layer; There is a horizontal difference between the m-th target layer formed by the first material and the m-th target layer formed by the second material, where 1≤m≤s.

35. A three-dimensional printing method for manufacturing a target object, the target object comprising a first plurality of layers and a second plurality of layers, characterized in that, include: The first multiple layers of the target object are formed using the target material; and A second plurality of layers are formed of the target object using a first material and a second material different from the first material, comprising: (a) Curing a first material to form a first portion of a first layer in a second plurality of layers, the first portion of the first layer having a first thickness; (b) Curing the second material to form a second portion of the first layer in a second plurality of layers, the second portion of the first layer having a second thickness greater than the first thickness; (c) Curing the first material to form a first portion of a second layer of a second plurality of layers on a first portion of the first layer, wherein the total thickness of the first portion composed of the first material is greater than the total thickness of the second portion composed of the second material; (d) Curing the second material to form a second portion of a second layer of a second plurality of layers on a second portion of the first layer, wherein the total thickness of the second portion composed of the second material is greater than the total thickness of the first portion composed of the first material; (e) Repeat steps (c) and (d) to form a second or more layers of the target object.

36. The three-dimensional printing method according to claim 35, characterized in that, in, The target material: - Same as the first material, or - Same as the second material, or -Different from the first material and the second material.

37. A three-dimensional printing method for manufacturing a target object, the target object comprising multiple target layers (1 to n, n ≥ 3), characterized in that, The 3D printing method includes: (a) Curing a first material to form a first portion of a first layer of a plurality of target layers, the first portion of the first layer having a first thickness; (b) Curing the second material to form a second portion of a first layer in a plurality of target layers, the second portion of the first layer having a second thickness greater than the first thickness; …… (c) Curing the i-th material (i≥3) to form the i-th portion of the first layer of a plurality of target layers, wherein the i-th portion of the first layer has an i-th thickness greater than the (i-1)-th thickness; (d) Curing the first material to form a first portion of a second layer of a plurality of target layers on a first portion of the first layer, wherein the total thickness of the first portion composed of the first material is greater than the total thickness of the i-th portion composed of the i-th material; (e) Curing the second material to form a second portion of a plurality of target layers on a second portion of the first layer, wherein the total thickness of the second portion composed of the second material is greater than the total thickness of the first portion composed of the first material; …… (f) Curing the i-th material to form the i-th portion of the second layer of a plurality of target layers on the i-th portion of the first layer, wherein the total thickness of the second portion composed of the i-th material is greater than the total thickness of the i-1 portion composed of the (i-1)-th material; (g) Repeat steps (d)-(f) to form multiple target layers of the target object; Among them, the first material, the second material, ..., the i-th material are all different.

38. A non-volatile storage medium, characterized in that, The non-volatile storage medium includes a stored program, wherein the program is configured to perform the 3D printing method according to any one of claims 1 to 25 or 27-38.

Images