Method for manufacturing three-dimensional texture structure on surface of substrate

Abstract

The present invention relates to a method for manufacturing a three-dimensional texture structure on the surface of a substrate. The method comprises: 1) importing a texture pattern into a digital exposure device by means of corresponding software in a computer; 2) placing a substrate, the surface of which is coated with a UV photosensitive coating, under the digital exposure device for curing; 3) starting the digital exposure device, projecting the texture pattern as a UV light image onto the photosensitive coating on the surface of the substrate, and performing partial exposure and pre-curing; 4) removing the coating material of a pre-cured weak area on the surface of the substrate; 5) using a UV light source to irradiate the surface of a sheet until curing is complete, to obtain a sheet having a three-dimensional texture structure. The present invention has the following effects: 1. greatly improved visual and tactile effects; 2. a greatly reduced difficulty of a synchronous registration process; 3. high-precision synchronization between a pattern in an image and the texture; 4. a mold does not need to be manufactured or replaced, and costs are low; 5. a curing working platform is fixed; and 6. production efficiency is effectively improved by using a pre-curing process, and resources are saved.

Description

A method for manufacturing a three-dimensional texture structure on a substrate surface Technical Field

[0001] The present invention relates to the technical field of plate processing, and in particular to a method for manufacturing a three-dimensional texture structure on the surface of a substrate through a novel process. Background Art

[0002] The architectural decoration industry has a huge demand for materials like wood and stone. However, due to limited natural resources, most current architectural decoration materials are printed to mimic natural materials like wood and stone. These materials are then combined with a variety of substrates (such as wood (particleboard, medium-density fiber "MDF"), high-density fiber "HDF"), or plywood), plastics (such as PVC, PET, and PP), cellulose-based materials (paper or cardboard), and metals). This approach conserves natural resources while meeting market demands. Because printed wood and stone grains can only achieve color simulation, a simultaneous patterning process is required to synchronize color and texture, ultimately creating a realistic visual and tactile effect. This simultaneous patterning process has always been a major challenge in the production of decorative materials. Currently, texture is achieved through embossing: a embossed pattern is first engraved on a steel plate or roller-type mold. The mold is then placed on the substrate and, using pressure, the texture from the mold is transferred to the substrate surface. This method has many disadvantages, such as: the texture length is limited due to mold size restrictions; the texture design is single and difficult to synchronize; the more texture designs, the higher the mold cost; changing molds during production affects production capacity, etc.

[0003] In the field of 3D printing, DLP (Digital Light Processing) technology primarily uses a projector (DLP optical machine) to cure a photosensitive polymer liquid layer by layer, creating a 3D printed object. As disclosed in US2017182708A1, each slice of the model to be printed corresponds to a black-and-white image (with any pixel in the image having only two possible values: 0 or 1). The projector then projects this binary image using ultraviolet light onto the photosensitive polymer liquid on the surface of the printed structure. Pixel 1 is illuminated by photons, causing the polymer liquid to undergo a thorough cross-linking and curing reaction. Pixel 0 is not illuminated by photons, causing the polymer liquid to remain liquid, thus creating a new solid layer stacked on top of the previous layer. This process is repeated until printing is complete. In this printing process, the projected image is binary, meaning that a given location can only be illuminated at full power or at zero power. Locations illuminated at full power receive sufficient energy for complete curing. Due to DLP power constraints and printing precision limitations, each slice is relatively thin, typically less than 1 mm. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the present invention aims to provide a method for manufacturing a three-dimensional texture structure on the surface of a substrate.

[0005] To achieve the above object, the technical solution adopted by the present invention is:

[0006] A method for producing a three-dimensional texture structure on a substrate surface, comprising:

[0007] Step 1: Prepare at least one digital exposure device and connect it to a computer, and import the processed texture pattern into the digital exposure device through the corresponding software in the computer for standby use;

[0008] Step 2: Prepare a substrate with a specific planar pattern on its surface and apply a UV photosensitive coating of equal thickness on its surface. The coating thickness can reach several mm.

[0009] Step 3: The coated substrate is transported by an automatic conveyor to a fixed exposure station to wait for curing. The digital exposure device is activated to project the pre-imported texture pattern onto the UV photosensitive coating on the substrate surface using a UV light image. Under the action of light, the photosensitive coating undergoes an incomplete cross-linking reaction, achieving selective exposure and pre-curing corresponding to the texture pattern. The incomplete cross-linking reaction is due to the low UV light power and the thick photosensitive coating. The coating molecules closer to the surface have more opportunities to absorb sufficient light energy to complete the cross-linking reaction and achieve curing.

[0010] Step 4: The coated pre-cured substrate is transferred to a cleaning station, where a cleaning mechanism removes most of the coating material in the weakly pre-cured areas on the substrate surface, leaving the coating in the strongly pre-cured areas, thereby obtaining a plate with a three-dimensional textured surface.

[0011] Step 5: Use a high-power UV light source to evenly irradiate the surface of the plate until the residual coating material on the surface of the plate is completely cured, thereby obtaining a plate having a three-dimensional texture structure corresponding to the texture pattern described in step 1 and expressed by the distribution of the cured residual coating material.

[0012] Furthermore, the main body of the digital exposure device is a DLP optical machine, and the number of the DLP optical machine is determined by the width of the substrate and the production capacity requirement. According to the demand, multiple digital exposure devices are spliced ​​together to perform exposure operations simultaneously.

[0013] Furthermore, in step 1, each pixel in the texture pattern can have a grayscale value, i.e., it does not have to be either black or white. The grayscale value is used to control the UV light intensity corresponding to the pixel location during step 3, thereby affecting the pre-curing degree of the coating material at the corresponding location on the substrate surface, and thus affecting the texture structure of the board surface after the coating material in the weakly pre-cured area is removed during step 4.

[0014] Furthermore, in step 2, the surface of the substrate is flat, and the planar pattern on the surface can be achieved by printing, imprinting, paving and other processes.

[0015] Furthermore, in step 2, the plane pattern on the surface of the substrate is related to the texture pattern in step 1: both are obtained by processing the same image separately, or one is obtained by processing the other.

[0016] Furthermore, in step 2, the coating is formed by coating the surface of the substrate.

[0017] Furthermore, in step 2, the coating thickness is determined based on the maximum height of the three-dimensional texture structure on the plate surface ultimately achieved by the solution of the present invention.

[0018] Furthermore, in step 2 and step 3, the process of coating the same substrate surface and projecting a UV light image for selective pre-curing is one-time, continuous, and non-repetitive.

[0019] Furthermore, in step 3, the wavelength of the UV light emitted by the digital exposure device is 320-700 nm.

[0020] Furthermore, in step 3, the selective exposure is to selectively perform UV light irradiation of different intensities or different durations according to the position where the texture pattern is projected on the photosensitive coating.

[0021] Furthermore, in step 3, the incomplete cross-linking reaction refers to the fact that when the photosensitive coating is exposed at the projection position according to the texture pattern, because the UV light intensity emitted by the digital exposure device is low and the exposure time is insufficient, the energy is insufficient to cause a complete cross-linking reaction in the photosensitive coating with a certain thickness, and the coating is not completely cured. This is manifested as only a part of the coating molecules being completely cured through the cross-linking reaction, while other molecules are still in the middle of the reaction or have not yet started to react.

[0022] Furthermore, in step 3, the pre-curing process is a stage where the photosensitive coating undergoes an incomplete cross-linking reaction. The pre-curing time typically ranges from 0.1 to 180 seconds, depending on the cleaning station requirements. Pre-curing should ensure that the desired portion of the coating reaches a certain degree of cure to facilitate cleaning in step 3.

[0023] Furthermore, in step 3, the curing power of the digital exposure equipment is 1-120W, and the curing speed is 1-500mm / s.

[0024] Furthermore, the output power of the exposure device is inversely proportional to the exposure time. When the output power of the exposure device is large, the required exposure time is short, and vice versa.

[0025] Furthermore, in step 3, the projection mode of the digital exposure device is a static mode or a dynamic mode.

[0026] Furthermore, when the digital exposure device uses a static mode light machine, the shadow range it projects is fixed.

[0027] Furthermore, when the digital exposure device uses a dynamic mode light machine, the pattern projected by the digital exposure device is dynamic and continuous.

[0028] Furthermore, in step 4, the cleaning method at the cleaning station is a physical method, including any one or more combinations of high-pressure water flushing, electrostatic adsorption, surface adsorption, etc.

[0029] Furthermore, in step 5, the residual coating is the portion of the pre-cured coating that remains on the surface of the substrate after passing through the cleaning station.

[0030] Furthermore, in step 5, the high-power UV light source is a device such as a high-pressure mercury lamp, a semiconductor laser, etc. that can generate a sufficiently high-power UV band light source.

[0031] Technical effect: The method of the present invention is to use DLP digital light processing technology to coat a certain thickness of photosensitive coating on the surface of the substrate for UV light pre-curing, remove the coating material in the area with weak pre-curing, retain the coating in the area with strong pre-curing, and then fully cure it at high power, thereby forming a three-dimensional texture on the surface. Compared with existing similar processes, the method of the present invention has the following effects: 1. It can achieve a corresponding and unique three-dimensional texture for each image, greatly improving the visual and tactile effects; 2. It is conducive to shortening the process flow and greatly reducing the difficulty of the synchronous pattern matching process; 3. It can quickly and accurately locate the working position, and the synchronization accuracy of the image and texture is high; 4. There is no need to make or replace molds, and the cost is low; 5. The curing work platform is fixed and does not require complex structural design; 6. The use of pre-curing technology effectively improves production efficiency and saves resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] FIG1 is a schematic diagram showing the connection of a DLP optical engine and related modules according to an embodiment of the present invention;

[0033] FIG2 is a schematic diagram showing the principle of forming a three-dimensional structure texture according to an embodiment of the present invention;

[0034] FIG3 is a schematic diagram of the processing of step 2 according to an embodiment of the present invention;

[0035] FIG4 is a schematic diagram of the processing of step 3 according to an embodiment of the present invention;

[0036] FIG5 is a schematic diagram of the processing of step 4 according to an embodiment of the present invention;

[0037] FIG6 is a processing schematic diagram of step 5 according to an embodiment of the present invention. DETAILED DESCRIPTION

[0038] In order to enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and implementation methods.

[0039] As shown in Figures 1-2, an embodiment of the present invention provides a method for manufacturing a three-dimensional texture structure on the surface of a substrate, which is a process of synchronously aligning patterns through a digital exposure device. Specifically, the main body of the digital exposure device 1 is a DLP optical machine, that is, the present invention adopts DLP digital light processing technology and is completed by a commercially available DLP optical machine. The DLP optical machine is connected to a main light source 2, and is also provided with a light source 3 connected to the main light source and hardware such as a power supply. The basic principle is to prepare a surface plate-like substrate 4, and apply a layer of liquid (usually UV paint) on its surface at one time to form a 2mm thick coating 5, and then pre-cure the coating 5 with light projected by the DLP optical machine lens, and selectively irradiate the surface of the photosensitive coating with UV light and exposure time in combination with the texture pattern to achieve an incomplete cross-linking reaction of the coating, forming pre-cured layers with different degrees of curing, removing the coating material in the area with a weaker degree of curing, and then irradiating the remaining coating with high-power UV to completely cure it, so that a three-dimensional structural texture can be obtained on the surface of the substrate; as shown in Figure 2. The method specifically includes the following steps:

[0040] Step 1: Prepare at least one digital exposure device 1 (i.e., a DLP light machine) and connect it to a computer. Use the corresponding software in the computer to import the processed texture pattern into the digital exposure device 1 for standby use. The texture pattern is stored in a bitmap format, where each pixel occupies 1 byte of data, i.e., has 256 gray levels.

[0041] Step 2: Prepare a plate-shaped substrate 4 having an imaging pattern on its surface. In this embodiment, the coating is formed by coating the substrate surface. For example, a single-roll or double-roll coater is used to apply a layer of UV coating to the substrate surface at one time to form a coating 5. The thickness of the coating 5 meets the height requirements of the three-dimensional texture structure and can be up to 2 mm. The coated substrate is then placed under a digital exposure device to wait for curing, as shown in FIG3 .

[0042] Step 3: The coated plate-like substrate 4 is transported by an automatic conveyor to a fixed exposure station to await curing. The digital exposure device 1 is activated to project a UV light image onto the photosensitive coating on the substrate surface according to the pre-introduced texture pattern, forming an exposure projection area on the surface of the plate-like substrate 4. The photosensitive coating in the projection area is controlled to undergo an incomplete cross-linking reaction under the action of light, thereby achieving selective exposure and pre-curing. As shown in Figure 4, t1, t2, t3, and t4 in the figure represent different exposure times t for different positions. This time is affected by the pattern information. A longer t results in a higher degree of pre-curing of the photosensitive coating.

[0043] Step 4: The substrate with partially cured coating is transferred to a cleaning station, where a cleaning mechanism 6 removes more coating material from the weakly pre-cured area on the surface of the substrate, and easily retains the coating from the strongly pre-cured area, thereby obtaining a plate with a three-dimensional texture structure on the surface. The cleaning method at the cleaning station is a physical method, including a cleaning mechanism 6 made of any one or more of high-pressure water flushing, electrostatic adsorption, surface adsorption, etc., and the actual situation determines whether to use high-pressure water flushing to remove the uncured coating, or to directly use high-pressure air to blow off the uncured coating, or to brush off the uncured coating with a metal brush, as shown in FIG5 ;

[0044] Step 5: The sheet is transferred to a radiation irradiation area to reinforce the pre-cured three-dimensional texture structure. A high-power UV light source is used to evenly irradiate the sheet surface to completely cure the residual coating on the sheet surface. This results in a sheet with a three-dimensional texture structure corresponding to the texture pattern described in Step 1, represented by the distribution of the cured residual coating material, as shown in Figure 6. Drying can be performed using either ambient air drying or high-temperature drying, with the high-temperature drying temperature ranging from 60° to 100°C and a drying speed of 10-30 m / s.

[0045] Specifically, in steps 1-3, the number of the digital exposure devices 1 is determined by the width of the substrate and the production capacity requirements. According to the needs, multiple DLP light machines are spliced ​​together to perform exposure operations at the same time. The multiple here should be understood as more than two. Connecting the automated equipment (digital exposure equipment) to the computer (i.e., PC terminal) and installing special software on the computer for control is an existing common technology and will not be described in detail here. The imaging pattern on the surface of the substrate can be processed and produced by digital printing, film lamination, etc.; for example, for wood grain flooring, the wood grain pattern can first be printed on a board using digital printing (i.e., to produce a background of a three-dimensional texture structure), and then UV paint can be applied on the background to form a coating. Specifically, in step 2, the surface of the substrate can be coated by printing, pressing, flat lamination, transfer, etc.; specifically, this embodiment uses a single-roller or double-roller coater to apply a layer of UV paint material on the surface of the substrate.

[0046] Specifically, in step 3, the wavelength of light emitted by the digital exposure device is 320-700 nm, and the pre-curing time is 0.1-180 s; the preferred wavelength is 320 nm, the pre-curing time is determined according to the texture pattern information, and the exposure time t at different positions is controlled by a curing algorithm combined with the pattern information.

[0047] Specifically, in step 3, the projection mode of the digital exposure device 1 is a static mode or a dynamic mode.

[0048] Specifically, when the digital exposure device 1 selects the static mode, the shadow range projected by it is fixed.

[0049] Specifically, when the digital exposure device 1 uses the dynamic mode, the pattern projected by the digital exposure device is dynamic and continuous. The digital exposure device 1 of this embodiment uses the dynamic mode, as shown in FIG4 .

[0050] Specifically, the curing power of the digital exposure device 1 is 1-120W, and the speed is 1-500mm / s; preferably, the curing power is 120W.

[0051] Specifically, in step 4, the cleaning method is a physical method, including a cleaning mechanism 6 made of any one of high-pressure water flushing, high-pressure air and a metal brush, that is, it is determined according to the actual situation whether to use high-pressure water flushing to remove the coating material in the weakly cured area or to directly use high-pressure air to blow off the coating material in the weakly cured area, or to brush off the weakly cured coating material with a metal brush; as shown in Figure 5.

[0052] In summary, the method of the present invention adopts DLP digital light processing technology to project and solidify areas of specific patterns; adopts a multi-wavelength light source, adjusts the output ratio of each wavelength and connects to an optical machine through optical fiber coupling, coats a photosensitive coating of a certain thickness on the surface of the substrate for UV pre-curing, removes the coating material in the area with weak pre-curing, retains the coating in the area with strong pre-curing, and then completely cures it with high-power UV light, thereby achieving an efficient curing effect; finally, a three-dimensional structure that conforms to the texture pattern is formed on the surface to achieve a texture effect.

[0053] In the above description, it should be noted that the terms "installed", "connected", "connected" and other corresponding terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, an indirect connection through an intermediate medium, or it can be a communication between the internal parts of two components.

[0054] Obviously, the embodiments described above are only some of the embodiments of the present invention, not all of them. The drawings provide preferred embodiments of the present invention, but do not limit the scope of the present invention. The present invention can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive. Any equivalent structure made by using the contents of the present description and drawings, directly or indirectly applied to other related technical fields, is also within the scope of protection of the present invention.

Claims

1. A method for producing a three-dimensional texture structure on a substrate surface, characterized in that: include: Step 1; Prepare at least one digital exposure device and connect it to a computer, and import the processed texture pattern into the digital exposure device through the corresponding software in the computer for standby use; Step 2: Prepare a substrate with a specific planar pattern on its surface and apply a layer of UV photosensitive coating of equal thickness on its surface; Step 3: The coated substrate is transported by an automatic conveyor to a fixed exposure station to wait for curing; The digital exposure device is started to project the pre-imported texture pattern onto the UV photosensitive coating on the substrate surface in the form of a UV light image. The photosensitive coating undergoes an incomplete cross-linking reaction under the action of light, achieving selective exposure and pre-curing corresponding to the texture pattern. Step 4: The coated pre-cured substrate from step 3 is transferred to a cleaning station. The cleaning mechanism removes most of the coating material in the weakly pre-cured areas on the substrate surface, making it easier to retain the coating in the strongly pre-cured areas, thereby obtaining a plate with a three-dimensional texture structure on the surface. Step 5: Use a high-power UV light source to evenly irradiate the surface of the plate in step 4 until the residual coating material on the surface of the plate is completely cured, thereby obtaining a plate having a three-dimensional texture structure corresponding to the texture pattern described in step 1 and expressed by the distribution of the cured residual coating material.

2. A method for producing a three-dimensional texture structure on a substrate surface according to claim 1, characterized in that The main body of the digital exposure equipment in step 1 is a DLP optical machine, and its number is determined by the width of the substrate and the production capacity requirements. According to demand, multiple digital exposure devices are spliced ​​together to perform exposure operations simultaneously.

3. A method for producing a three-dimensional texture structure on a substrate surface according to claim 1, characterized in that Each pixel in the texture pattern in step 1 has a grayscale value, and the grayscale value is used to control the UV light intensity corresponding to the pixel position when implementing step 3.

4. A method for producing a three-dimensional texture structure on a substrate surface as claimed in claim 1, characterized in that In step 2, the surface of the substrate is flat, and the flat pattern on the surface is achieved through printing, imprinting, paving and other processes.

5. The method for producing a three-dimensional texture structure on a substrate surface according to claim 1, wherein The UV photosensitive coating in step 2 is formed by coating the surface of the substrate.

6. A method for producing a three-dimensional texture structure on a substrate surface as claimed in claim 1, characterized in that In step 2 and step 3, the same substrate surface is coated with a coating and a UV light pattern is projected for selective pre-curing, which is a one-time, continuous, and non-repetitive process.

7. A method for producing a three-dimensional texture structure on a substrate surface as claimed in claim 1, characterized in that The wavelength of UV light emitted by the digital exposure device in step 3 is 320-700nm; the pre-curing time is generally 0.1-180s; The curing power of the digital exposure equipment is 1-120W and the speed is 1-500mm / s.

8. The method for producing a three-dimensional texture structure on a substrate surface according to claim 1, wherein The projection mode of the digital exposure device in step 3 is a static mode or a dynamic mode; when the digital exposure device uses a static mode light machine, the shadow range it projects is fixed; when the digital exposure device uses a dynamic mode light machine, the pattern projected by the digital exposure device is dynamic and continuous.

9. The method for producing a three-dimensional texture structure on a substrate surface according to claim 1, wherein The cleaning method at the cleaning station in step 4 is a physical method, including any one of high-pressure water washing, electrostatic adsorption, and surface adsorption.

10. The method for producing a three-dimensional texture structure on a substrate surface according to claim 1, wherein In step 5, the high-power UV light source is a device such as a high-pressure mercury lamp, a semiconductor laser, etc. that can generate a sufficiently high-power UV band light source.

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