Multi-iridescent optically variable printing device and method of printing, readable storage medium

Abstract

The application provides a multi-optical color optically variable printing device and a printing method thereof and a readable storage medium. The multi-optical color optically variable printing device comprises a conveying unit, a screen printing unit for printing ink or varnish containing magnetic substances on a printing substrate, and a plurality of multi-optical color optically variable pattern forming units. Each multi-optical color optically variable pattern forming unit comprises a magnetized roller provided with a magnetic orientation member for magnetically orienting the printing substrate, and a pre-drying solidifier for pre-drying and solidifying the printing substrate. The pre-drying solidifier comprises an optical mask solidification device fixedly arranged for projecting a dynamic and refreshable variable light field image, and the variable light field image moves synchronously with the printing substrate by a predetermined distance. Through the technical scheme of the application, omnidirectional splicing of fixed and variable multi-optical color optically variable images can be completed, that is, splicing in any direction.

Description

[0001] This application is a divisional application of Chinese patent application filed on April 22, 2022, with application number "202210429178.2" and entitled "Multi-color Optical Variable Printing Apparatus and Printing Method Thereof, and Readable Storage Medium". Technical Field

[0002] This invention relates to the field of anti-counterfeiting printing technology, and more specifically, to a multi-color optical variable printing device and its printing method, as well as a readable storage medium. Background Technology

[0003] Optical color-changing technology refers to the technique of producing dynamic optical color-changing phenomena after optically variable magnetic ink is screen-printed and magnetically oriented. Currently, for the same screen-printed pattern, printing equipment can only achieve a single effect of optical color-changing technology, that is, to achieve a rolling effect under the action of a single magnetic field, or to achieve a changing effect under the action of a composite magnetic field. There is no multi-color optical color-changing technology that can achieve two or more effects at the same time. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0005] In view of this, the first objective of the present invention is to provide a multi-color optical variable printing apparatus.

[0006] The second objective of this invention is to provide a multi-color optical variable printing method.

[0007] A third objective of this invention is to provide a multi-color optical variable printing apparatus.

[0008] A fourth objective of this invention is to provide a readable storage medium.

[0009] To achieve the above objectives, the first aspect of the present invention provides a multi-color optical variable printing apparatus, comprising: a conveying unit for conveying a substrate; a screen printing unit for printing ink or varnish containing magnetic material onto the substrate; and multiple optical variable pattern forming units, each of which forms an optical variable pattern in a different area of ​​the substrate. Each optical variable pattern forming unit includes: a magnetized roller with a magnetic orientation component for magnetically orienting the substrate; and a pre-drying and curing unit for pre-drying and curing the substrate. The conveying unit, screen printing unit, and multiple optically variable pattern forming units are sequentially arranged in the conveying direction of the substrate. At least two optically variable pattern forming units have magnetic orientation components with different magnetization effects. A pre-drying curing unit is positioned opposite to the magnetic orientation component. During the magnetic orientation process, the pre-drying curing unit simultaneously pre-dries and cures the substrate. The pre-drying curing unit includes an optical mask curing device, which is fixedly positioned to project a dynamically refreshable variable light field image. The variable light field image moves synchronously with the substrate for a predetermined distance.

[0010] The multi-color optical variable printing apparatus provided by the present invention includes a conveying unit, a screen printing unit, and multiple optical variable pattern forming units. The conveying unit conveys the substrate, and the screen printing unit, located in the next step after the conveying unit, is used to imprint ink or varnish containing magnetic material onto the substrate conveyed by the conveying unit, forming a semi-finished product. The multiple optical variable pattern forming units, located in the next step after the screen printing unit, are used to form optical variable patterns on the semi-finished product. Each optical variable pattern forming unit includes a magnetized roller and a pre-drying and curing unit. The magnetized roller is provided with a magnetic orientation component, which is used to magnetically orient the substrate, and the pre-drying and curing unit is used to pre-dry and cure the substrate. At least two optical variable pattern forming units have magnetic orientation components with different magnetization effects. The pre-drying and curing units are arranged opposite each other outside the magnetic orientation components, and during the magnetic orientation process of the magnetic orientation components, the pre-drying and curing units simultaneously pre-dry and cure the substrate. The pre-drying curing unit includes an optical mask curing device, which projects a dynamically refreshable variable light field image. The image formed by the variable light field illuminates the substrate on the magnetized roller, moving synchronously with the substrate. The ink or varnish on the substrate is pre-dried, enabling omnidirectional splicing of fixed and variable multi-color optically variable images, i.e., splicing in any direction. The optical mask curing device is fixedly installed. It should be noted that "fixed installation" means that the optical mask curing device is fixed during continuous production after the product is determined. When product specifications change, the optical mask curing device can be moved along the axial direction of the magnetized roller to accommodate different product specifications. By setting magnetic orientation components with different magnetic field effects and using an optical mask curing device capable of precise curing as the pre-drying curing unit, multiple color-changing effects can be achieved for multiple areas of the same screen-printed pattern, enabling omnidirectional splicing of multiple fixed-effect images, as well as omnidirectional splicing of variable and fixed-effect images. Multiple effects can be rolling effects under the action of multiple single magnetic fields, motion effects under the action of multiple composite magnetic fields, or rolling effects under the action of a single magnetic field and motion effects under the action of a composite magnetic field.

[0011] In this process, while the substrate moves synchronously with the magnetized roller—that is, during the continuous magnetization of the substrate—the optical mask curing device projects high-refresh-rate moving images. The control system uses sensors, such as rotary encoders and grating rulers, to collect the position and speed of the substrate, conveyor, or magnetized roller, and controls the projected images to move synchronously with the substrate. The mechanical body of the optical mask curing device remains stationary. Synchronous movement of the images with the substrate means that the projected images and the substrate move at the same speed, and the position of the images projected onto the substrate is fixed relative to the substrate. The relative position of the images can be adjusted by changing the relevant parameters of the synchronization control as needed. This synchronous projection control method of the optical mask curing device solves the problem of continuous substrate production, namely, the magnetization, orientation, and precise curing of the pattern on the substrate during continuous high-speed movement. It also solves the problem of registration with existing printed patterns on the substrate; that is, adjusting the synchronization control parameters can ensure precise registration between the projected images and the existing printed patterns on the substrate.

[0012] It is understandable that, due to the principle that the OVMP pigment flakes in the ink form a certain angle with the substrate, the magnetic orientation effect of the OVMP pigment flakes in the photochromic magnetic ink remains effective until the ink is pre-cured, cured, or naturally penetrated and dried. Therefore, magnetic orientation can be performed twice or more during this period, thereby achieving multi-color photochromic technology with two or more effects on the same screen-printed pattern.

[0013] In addition, the technical solution provided in this application may also have the following additional technical features:

[0014] In the above technical solution, the multi-color optical variable printing device includes a sensor for collecting position and speed information of the substrate; the optical mask curing device includes a light source for emitting light; a controller for receiving position and speed information from the sensor, and also for receiving, storing, and processing projection image data, and generating control signals based on the position and speed information and the projection image data; a lens; and a spatial light modulator for receiving light emitted by the light source and the control signals to project a variable light field image through the lens; wherein the spatial light modulator includes one of the following: a digital micromirror (DMD), a liquid crystal spatial light modulator, and an acousto-optic modulator.

[0015] In this technical solution, the multi-color optical variable printing device includes sensors for acquiring the position and speed information of the substrate. The optical mask curing device includes a light source, a controller, a lens, and a spatial light modulator. The controller receives the position and speed information from the sensors, and also receives, stores, and processes the projection image data, and generates control signals based on the position and speed information and the projection image data. The spatial light modulator receives the light emitted by the light source and the control signals to project a variable light field image through the lens. The spatial light modulator can be a digital micromirror (DMD), a liquid crystal spatial light modulator, or an acousto-optic modulator. Specifically, during the continuous magnetization of the substrate, the optical mask curing device can project a high refresh rate moving image. The control system acquires the position and speed information of the substrate through sensors and controls the image projected by the optical mask curing device to move synchronously with the substrate. The synchronous projection control method of the optical mask curing device solves the problem of continuous substrate production, that is, the substrate completes the magnetization orientation and precise curing of the pattern during continuous high-speed movement, which can make the projected image accurately registered with the existing printed pattern on the substrate.

[0016] In the above technical solution, the optical mask curing device also includes a heat dissipation component, which is used to dissipate heat from the spatial light modulator and / or the light source.

[0017] In this technical solution, the optical mask curing device also includes a heat dissipation component. The heat dissipation component is used to dissipate heat from the spatial light modulator or the light source.

[0018] In the above technical solution, the light source includes a UV-LED light source or a laser light source, and the wavelength of the light emitted by the light source is 350nm~425nm.

[0019] In this technical solution, a DLP optomechanical system based on a digital micromirror (DMD) is used as an optical mask curing device to pre-dry and cure inks or varnishes. The light source can be a UV-LED light source or a laser light source, and the wavelength of the light emitted by the light source can be selected from 350nm to 425nm.

[0020] In the above technical solution, the variable light field graphic includes one of the following: graphics, text, numbers, serial numbers, barcodes, and QR codes.

[0021] In this technical solution, the variable light field image can be a graphic, text, number, serial number, barcode, or QR code.

[0022] In the above technical solution, the pre-drying curing unit includes multiple optical mask curing devices, which are spaced apart in the axial direction of the magnetized roller.

[0023] In this technical solution, there can be multiple optical mask curing devices, which are spaced apart in the axial direction of the magnetized roller. The optical mask curing devices can be used in combination according to the size of the substrate.

[0024] In the above technical solution, the pre-drying curing device also includes a curing device adjustment mechanism, which includes a fixed crossbeam, a motor and a guide rail. The fixed crossbeam extends along the axial direction of the magnetized roller, and the optical mask curing device is mounted on the fixed crossbeam. The motor drives the optical mask curing device to move along the fixed crossbeam.

[0025] In this technical solution, the pre-drying curing unit also includes a curing device adjustment mechanism, which includes a fixed crossbeam, a motor and a guide rail. The fixed crossbeam extends along the long axis of the magnetized roller, and the optical mask curing device is mounted on the fixed crossbeam. The motor drives the optical mask curing device to move along the fixed crossbeam, thereby adjusting the interval distance of the optical mask curing device.

[0026] In the above technical solution, the multi-color optical variable printing device also includes: a transfer system, which includes multiple transfer rollers and is used to transfer the substrate.

[0027] In this technical solution, the multi-color optical variable printing device also includes a transfer system, which includes multiple transfer rollers for sequentially transferring the substrate on the conveying unit, the screen printing unit, multiple optical variable pattern forming units, and the drying and curing unit.

[0028] In the above technical solution, the multi-color optical variable printing device further includes: a first rearrangement magnetization device, which is disposed between the screen printing unit and the optical variable pattern forming unit; and a second rearrangement magnetization device, which is disposed between multiple optical variable patterns.

[0029] In this technical solution, the multi-color optical variable printing apparatus also includes a first rearrangement magnetization device and a second rearrangement magnetization device. The first rearrangement magnetization device is located between the screen printing unit and the optical variable pattern forming unit, while the second rearrangement magnetization device is located between multiple optical variable patterns. It can be understood that the substrate travels from the screen printing unit to the first rearrangement magnetization device before entering the optical variable pattern forming unit, and then passes through the second rearrangement magnetization device before entering the second optical variable pattern forming unit. When ink or varnish is printed on the substrate, the magnetic pigment flakes are arranged randomly. When such a substrate is conveyed to the first and second rearrangement magnetization devices, the magnetic pigment flakes are rearranged according to a certain pattern, such as aligning parallel to the substrate. This improves the consistency of magnetization orientation of the magnetic pigment flakes as they pass through the magnetic orientation component, resulting in a brighter optical variable effect.

[0030] In the above technical solutions, the ink or varnish includes photochromic ink, curing varnish, or other types of UV-curable ink.

[0031] In this technical solution, the ink or varnish can be a photochromic ink, a curing varnish, or other types of UV-curable ink.

[0032] In the above technical solution, the printing substrate includes one of the following: paper, plastic sheet, and metal sheet.

[0033] In this technical solution, the printing substrate can be paper, plastic sheet, or metal sheet.

[0034] In the above technical solution, the multi-color optical variable printing device also includes a drying and curing unit, which is located downstream of multiple optical variable pattern forming units and is used to dry and cure the substrate.

[0035] In this technical solution, the multi-color optical variable printing device also includes a drying and curing unit, which is located downstream of multiple optical variable pattern forming units and is used to dry and cure the substrate.

[0036] The second aspect of the present invention provides a multi-color optical variable printing method, comprising: printing ink or varnish containing magnetic material on a substrate through a screen printing unit to form a semi-finished product; sequentially conveying the semi-finished product to multiple optical variable pattern forming units, and simultaneously pre-drying and curing the semi-finished product by magnetic orientation components and pre-drying curing units to form optical variable patterns in different areas of the substrate, thereby forming a multi-color optical variable product; wherein, at least two optical variable pattern forming units have magnetic orientation components with different magnetization effects, and the pre-drying curing unit includes an optical mask curing device, which is fixedly set to project a dynamically refreshable variable light field image, the variable light field image moving synchronously with the substrate at a predetermined distance.

[0037] According to the multi-color optical variable printing method provided in this application, ink or varnish containing magnetic materials is first printed on the substrate to form a semi-finished product. Then, the semi-finished product is sequentially passed through multiple optical variable pattern forming units. The semi-finished product is magnetically oriented and pre-dried / cured simultaneously by a magnetic orientation component and a pre-drying curing unit, thereby forming optical variable patterns in different areas of the substrate, thus creating a multi-color optical variable product. At least two optical variable pattern forming units have magnetic orientation components with different magnetization effects. The pre-drying curing unit includes an optical mask curing device, which projects dynamically refreshable variable light field images. The variable light field images move synchronously with the substrate, thereby achieving two or more magnetization positioning and pre-curing drying for the same screen-printed image, completing the omnidirectional splicing of fixed and variable multi-color optical variable images, i.e., splicing in any direction.

[0038] The above technical solution also includes the following method for multi-color optical variable printing: after the semi-finished product is sequentially conveyed to multiple optical variable pattern forming units, the multi-color optical variable product is conveyed to the drying and curing unit for drying and curing.

[0039] In this technical solution, after the semi-finished product is sequentially conveyed to multiple optically variable pattern forming units, the optically variable product is conveyed to a drying and curing unit for drying and curing, thereby obtaining the final product.

[0040] In the above technical solution, the optical mask curing device includes: a light source for emitting light; a controller for receiving position and velocity information of the semi-finished product collected by the sensor, and also for receiving, storing, and processing projection image data, and generating control signals based on the position and velocity information and the projection image data; a lens; and a spatial light modulator for receiving light emitted by the light source and the control signal to project a variable light field image through the lens; wherein the spatial light modulator includes one of the following: a digital micromirror (DMD), a liquid crystal spatial light modulator, and an acousto-optic modulator.

[0041] In this technical solution, the optical mask curing device includes a light source, a controller, a lens, and a spatial light modulator. The controller receives position and velocity information from sensors, and also receives, stores, and processes the projected graphic data, generating control signals based on the position and velocity information and the projected graphic data. The spatial light modulator receives light emitted by the light source and the control signals to project a variable light field graphic through the lens. The spatial light modulator can be a digital micromirror (DMD), a liquid crystal spatial light modulator, or an acousto-optic modulator. Specifically, during the continuous magnetization of the substrate, the optical mask curing device can project a high refresh rate moving graphic. The control system collects the position and velocity information of the substrate through sensors and controls the projected graphic to move synchronously with the substrate. The synchronous projection control method of the optical mask curing device solves the problem of continuous substrate production, that is, the substrate completes the magnetization orientation and precise curing of the pattern during continuous high-speed movement, enabling precise registration of the projected graphic with the existing printed pattern on the substrate.

[0042] To achieve the third objective of the present invention, the technical solution of the third aspect of the present invention provides a multi-color optical variable printing apparatus, comprising: a memory and a processor, wherein the memory stores a program or instructions that can be executed on the processor, and when the processor executes the program or instructions, it implements the steps of the multi-color optical variable printing method of any one of the technical solutions of the second aspect, and thus has the technical effects of any of the technical solutions of the second aspect, which will not be repeated here.

[0043] To achieve the fourth objective of this application, the technical solution of the fourth aspect of this application provides a readable storage medium storing a program or instructions thereon. When the program or instructions are executed by a processor, they implement the steps of the multi-color optical variable printing method of any one of the technical solutions of the second aspect, and thus have the technical effects of any of the technical solutions of the second aspect, which will not be repeated here.

[0044] Additional aspects and advantages of the invention will become apparent in the following description or may be learned by practice of the invention. Attached Figure Description

[0045] Figure 1 This is a schematic diagram of the structure of a multi-color optical variable printing apparatus according to an embodiment of the present invention;

[0046] Figure 2 This is a partial structural schematic diagram of a multi-color optical variable printing apparatus according to an embodiment of the present invention;

[0047] Figure 3 This is a partial structural schematic diagram of a multi-color optical variable printing apparatus according to an embodiment of the present invention;

[0048] Figure 4 This is a partial structural schematic diagram of a multi-color optical variable printing apparatus according to an embodiment of the present invention;

[0049] Figure 5 This is a partial structural schematic diagram of a multi-color optical variable printing apparatus according to an embodiment of the present invention;

[0050] Figure 6 A schematic block diagram of an optical mask curing apparatus according to an embodiment of the present invention;

[0051] Figure 7 This is a schematic block diagram of the structure of a multi-color optical variable printing apparatus according to an embodiment of the present invention;

[0052] Figure 8 This is a partial structural schematic diagram of a multi-color optical variable printing apparatus according to an embodiment of the present invention;

[0053] Figure 9 This is a schematic diagram illustrating the working principle of a multi-color optical variable printing apparatus according to an embodiment of the present invention;

[0054] Figure 10 This is a schematic diagram illustrating the working principle of a multi-color optical variable printing apparatus according to an embodiment of the present invention;

[0055] Figure 11 This is a schematic diagram illustrating the working principle of a multi-color optical variable printing apparatus according to an embodiment of the present invention;

[0056] Figure 12This is a flowchart of the steps of a multi-color optical variable printing method according to an embodiment of the present invention;

[0057] Figure 13 This is a flowchart of the steps of a multi-color optical variable printing method according to an embodiment of the present invention.

[0058] in, Figures 1 to 13 The correspondence between the reference numerals and the component names in the attached drawings is as follows:

[0059] The system includes: 10+ color-changing printing units, 100 conveyor units, 110 screen printing units, 130 magnetized rollers, 132 magnetic orientation components, 160 pre-drying and curing units, 210 fixed crossbeams, 220 motors, 230 optical mask curing devices, 232 light sources, 234 controllers, 236 lenses, 238 spatial light modulators, 240 heat dissipation components, 250 linear guides, 280 first rearrangement magnetization devices, 290 second rearrangement magnetization devices, 370 drying and curing units, 380 transfer systems, 500 substrates, 510 printing ink areas, 300 memory, and 400 processors. Detailed Implementation

[0060] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0061] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0062] The following reference Figures 1 to 13 Some embodiments of the present invention are described.

[0063] like Figure 1As shown, a multi-color optical variable printing apparatus 10 according to an embodiment of the present invention includes: a conveying unit 100 for conveying a substrate 500; a screen printing unit 110 for printing ink or varnish containing magnetic material on the substrate 500; and a plurality of optical variable pattern forming units, each of which is used to form optical variable patterns in different areas of the substrate 500. Each optical variable pattern forming unit includes: a magnetized roller 130, on which a magnetic orientation member 132 is disposed, the magnetic orientation member 132 being used to magnetically orient the substrate 500; and a pre-drying and curing unit 160, which is used to pre-dry and cure the substrate 500. The feeding unit 100, the screen printing unit 110, and multiple optically variable pattern forming units are arranged sequentially in the conveying direction of the substrate 500. Among them, the magnetic orientation components 132 of at least two optically variable pattern forming units have different magnetization effects. The pre-drying curing unit 160 is arranged opposite to the magnetic orientation component 132. During the process of magnetic orientation of the substrate 500 by the magnetic orientation component 132, the pre-drying curing unit 160 simultaneously pre-dries and cures the substrate 500. The pre-drying curing unit 160 includes an optical mask curing device 230, which is fixedly arranged to project a dynamically refreshable variable light field image. The variable light field image moves synchronously with the substrate 500 at a predetermined distance.

[0064] The multi-color optical variable printing apparatus 10 provided by the present invention includes a conveying unit 100, a screen printing unit 110, and multiple optical variable pattern forming units. The conveying unit 100 is used to convey a substrate 500. The screen printing unit 110 is located in the next step after the conveying unit 100 and is used to imprint ink or varnish containing magnetic material onto the substrate 500 conveyed by the conveying unit 100 to form a semi-finished product. The multiple optical variable pattern forming units are located in the next step after the screen printing unit 110 and are used to form optical variable patterns on the semi-finished product. Each optical variable pattern forming unit includes a magnetized roller 130 and a pre-drying and curing unit 160. The magnetized roller 130 is provided with a magnetic orientation member 132, which is used to magnetically orient the substrate 500. The pre-drying and curing unit 160 is used to pre-dry and cure the substrate 500. In this design, at least two magnetic orientation components 132 of the optically variable pattern forming unit have different magnetization effects. A pre-drying and curing unit 160 is positioned opposite to the magnetic orientation components 132 on the outside. During the magnetic orientation process of the magnetic orientation components 132 on the substrate 500, the pre-drying and curing unit 160 simultaneously pre-dries and cures the substrate 500. The pre-drying and curing unit 160 includes an optical mask curing device 230, which projects a dynamically refreshable variable light field image. The image formed by the variable light field illuminates the substrate 500 on the magnetized roller 130 and moves synchronously with the substrate 500. The ink or varnish on the substrate 500 is pre-dried, thus enabling omnidirectional splicing of fixed and variable optically variable images, i.e., splicing in any direction. The optical mask curing device 230 is fixedly positioned, meaning it remains fixed throughout continuous production after the product is finalized. It should be noted that "fixed setting" refers to the optical mask curing device 230 being fixed during continuous production after the product is determined. When product specifications change, the optical mask curing device 230 can be moved along the axial direction of the magnetized roller 130 to accommodate different product specifications. By setting magnetic orientation components 132 with different magnetic field effects and optical mask curing devices 230 capable of precise curing as pre-drying curing units 160, multiple glossy and optically variable effects can be achieved for multiple areas of the same screen-printed pattern, enabling omnidirectional splicing of multiple fixed-effect graphics and graphics, as well as omnidirectional splicing of variable-effect graphics and fixed-effect graphics. Multiple effects can be rolling effects under multiple single magnetic fields, motion effects under multiple composite magnetic fields, or rolling effects under a single magnetic field and motion effects under composite magnetic fields. The ink or varnish can be glossy and optically variable ink, curing varnish, or other types of UV-curable ink. The substrate 500 can be paper, plastic sheet, or metal sheet.

[0065] Specifically, while the substrate 500 moves synchronously with the magnetized roller 130, i.e., during the continuous magnetization of the substrate 500, the optical mask curing device 230 projects high-refresh-rate moving images and text. The control system, through sensors such as rotary encoders and grating rulers, collects the position and speed of the substrate 500, the conveyor, or the magnetized roller 130, and controls the projected images and text of the optical mask curing device 230 to move synchronously with the substrate 500. The mechanical body of the optical mask curing device 230 remains stationary. Synchronous movement of the images and text with the substrate 500 means that the projected images and text move at the same speed as the substrate 500, and the position of the images and text projected onto the substrate 500 is fixed relative to the substrate 500. The relative position of the images and text can be adjusted by changing the relevant parameters of the synchronization control as needed. The synchronous projection control method of the optical mask curing device 230 solves the problem of continuous production of the substrate 500, that is, the substrate 500 completes the magnetization orientation and precise curing of the pattern in continuous high-speed movement, and solves the problem of registration with the existing printed pattern on the substrate 500. That is, by adjusting the synchronous control parameters, the projected image can be accurately registered with the existing printed pattern on the substrate 500.

[0066] It is understandable that, due to the principle that the OVMP pigment flakes in the ink form a certain angle with the substrate 500, the magnetic orientation effect of the OVMP pigment flakes in the photochromic magnetic ink remains effective until the OVMP pigment flakes are pre-cured, cured, or naturally penetrated and dried. Therefore, magnetic orientation can be performed twice or more during this period, thereby achieving multi-color photochromic technology with two or more effects on the same screen-printed pattern.

[0067] like Figure 5 and Figure 6As shown, the multi-color optical variable printing apparatus 10 further includes a sensor for acquiring position and speed information of the substrate 500. The optical mask curing apparatus 230 includes a light source 232, a controller 234, a lens 236, and a spatial light modulator 238. The controller 234 receives the position and speed information from the sensor, and also receives, stores, and processes the projection image data, and generates a control signal based on the position and speed information and the projection image data. The spatial light modulator 238 receives the light emitted by the light source 232 and the control signal to project a variable light field image through the lens 236. The spatial light modulator 238 can be a digital micromirror (DMD), a liquid crystal spatial light modulator, or an acousto-optic modulator. Specifically, during the continuous magnetization of the substrate 500, the optical mask curing apparatus 230 can project a high refresh rate motion image. The control system acquires the position and speed information of the substrate 500 through the sensor and controls the image projected by the optical mask curing apparatus 230 to move synchronously with the substrate 500. The synchronous projection control method of the optical mask curing device 230 solves the problem of continuous production of the substrate 500. That is, the substrate 500 completes the magnetization orientation and precise curing of the pattern in continuous high-speed movement, which can make the projected image and the existing printed pattern on the substrate 500 accurately registered.

[0068] Furthermore, the optical mask curing apparatus 230 also includes a heat dissipation assembly 240. The heat dissipation assembly 240 is used to dissipate heat from the spatial light modulator 238 or from the light source 232.

[0069] Specifically, there can be multiple optical mask curing devices 230, which are spaced apart in the axial direction of the magnetizing roller 130. The optical mask curing devices 230 can be used in combination according to the size of the substrate 500.

[0070] In the above embodiments, the variable graphic text can be any graphic text, such as graphics, text, numbers, serial numbers, barcodes, QR codes, etc.

[0071] like Figure 2 and Figure 3As shown, in the above embodiment, the pre-drying curing unit 160 further includes a curing device adjustment mechanism. This mechanism includes a fixed crossbeam 210, a motor 220, and guide rails. The fixed crossbeam 210 extends along the axial direction of the magnetized roller 130. Optical mask curing devices 230 are mounted on the fixed crossbeam 210. The motor 220 drives the optical mask curing devices 230 to move along the fixed crossbeam 210, thereby adjusting the spacing between the optical mask curing devices 230. The fixed crossbeam 210 includes a horizontal plate and a vertical plate connected together. The motor 220 is mounted on the horizontal plate. The guide rail includes a linear guide rail 250 and a curing device guide rail. The linear guide rail 250 is mounted on the horizontal plate, and the curing device guide rail is mounted on the vertical plate. Multiple optical mask curing devices 230 are respectively connected to the linear guide rail 250, enabling them to move on the fixed crossbeam 210.

[0072] In the above embodiments, the multi-color optical variable printing apparatus 10 further includes a transfer system 380, which includes a plurality of transfer rollers for sequentially transferring the substrate 500 on the transport unit 100, the screen printing unit 110, the plurality of optical variable pattern forming units, and the optional drying and curing unit 370 described below.

[0073] like Figure 4 As shown, in some embodiments, the multi-color optical variable printing apparatus 10 further includes a first rearrangement magnetization device 280 and a second rearrangement magnetization device 290. The first rearrangement magnetization device 280 is disposed between the screen printing unit 110 and the color-changing pattern forming unit, and the second rearrangement magnetization device 290 is disposed between the multiple color-changing pattern forming units. It can be understood that the substrate 500 travels from the screen printing unit 110 to the first rearrangement magnetization device 280 before entering the first color-changing pattern forming unit, and then passes from the first color-changing pattern forming unit through the second rearrangement magnetization device 290 before entering the second color-changing pattern forming unit. When ink or varnish is printed on the substrate 500, the magnetic pigment flakes inside are arranged randomly and irregularly. When such a substrate 500 is conveyed to the first rearrangement magnetization device 280 and the second rearrangement magnetization device 290, the magnetic pigment flakes are rearranged according to a certain pattern, such as being arranged parallel to the substrate 500. This improves the consistency of the magnetization orientation of the magnetic pigment flakes when passing through the magnetization roller 130, thereby making the glossy effect brighter.

[0074] In the above embodiments, the multi-color optical variable printing apparatus 10 further includes a drying and curing unit 370, which is disposed downstream of the multiple optical variable pattern forming units and is used to dry and cure the substrate 500.

[0075] like Figure 12 As shown, an embodiment of the second aspect of the present invention provides a multi-color optical variable printing method, comprising:

[0076] Step S102: Print ink or varnish containing magnetic material onto the substrate using a screen printing unit to form a semi-finished product;

[0077] Step S104: The semi-finished product is sequentially conveyed to multiple optical variable pattern forming units. The semi-finished product is magnetically oriented and pre-dried and cured by the magnetic orientation component and pre-drying curing unit of the optical variable pattern forming unit, so as to form optical variable patterns in different areas of the substrate, thereby forming a multi-color product.

[0078] Among them, the magnetic orientation components of at least two optically variable pattern forming units have different magnetization effects, and the pre-drying curing unit includes an optical mask curing device, which is fixedly set to project a dynamically refreshable variable light field image, and the variable light field image moves synchronously with the substrate at a predetermined distance.

[0079] In this embodiment, ink or varnish containing magnetic material is first printed onto the substrate to form a semi-finished product. Then, the semi-finished product is sequentially passed through multiple optically variable pattern forming units. Simultaneously, magnetic orientation components and a pre-drying curing unit magnetically orient the semi-finished product while pre-drying and curing it, forming optically variable patterns in different areas of the substrate, thus creating a multi-color-changing product. At least two optically variable pattern forming units have magnetic orientation components with different magnetization effects. The pre-drying curing unit includes an optical mask curing device that projects dynamically refreshable variable light field images. The variable light field images move synchronously with the substrate, thereby achieving two or more magnetization positioning and pre-curing drying for the same screen-printed image. This completes the omnidirectional splicing of fixed and variable multi-color-changing images, i.e., splicing in any direction.

[0080] like Figure 13 As shown, the multi-color optical variable printing method provided in the above embodiments further includes the following steps:

[0081] Step S202: After the semi-finished product is sequentially conveyed to multiple optically variable pattern forming units, the optically variable product is conveyed to the drying and curing unit for drying and curing.

[0082] In this embodiment, after the semi-finished product is sequentially conveyed to multiple optically variable pattern forming units, the optically variable product is conveyed to a drying and curing unit for drying and curing, thereby obtaining the final product.

[0083] In the above embodiments, the optical mask curing apparatus includes a light source, a controller, a lens, and a spatial light modulator. The controller receives position and velocity information from sensors, and also receives, stores, and processes projection image data, generating control signals based on the position and velocity information and the projected image data. The spatial light modulator receives light emitted by the light source and the control signals to project a variable light field image through the lens. The spatial light modulator can be a digital micromirror (DMD), a liquid crystal spatial light modulator, or an acousto-optic modulator. Specifically, during the continuous magnetization of the substrate, the optical mask curing apparatus can project high-refresh-rate moving images. The control system collects the position and velocity information of the substrate through sensors and controls the projected image to move synchronously with the substrate. The synchronous projection control method of the optical mask curing apparatus solves the problem of continuous substrate production, that is, the substrate completes the magnetization orientation and precise curing of the pattern during continuous high-speed movement, enabling precise registration of the projected image with the existing printed pattern on the substrate.

[0084] like Figure 7 As shown, an embodiment of the third aspect of this application provides a multi-color optical variable printing apparatus 10, including a memory 300 and a processor 400. The memory 300 stores a program or instructions that can be executed on the processor 400. When the processor 400 executes the program or instructions, it implements the steps of the multi-color optical variable printing method of any one of the embodiments of the second aspect, and thus has the technical effects of any embodiment of the second aspect, which will not be repeated here.

[0085] An embodiment of the fourth aspect of this application provides a readable storage medium having a program or instructions stored thereon. When the program or instructions are executed by a processor, they implement the steps of the multi-color optical variable printing method of any one of the embodiments of the second aspect, and thus have the technical effects of any embodiment of the second aspect described above, which will not be repeated here.

[0086] like Figures 1 to 13As shown, a multi-color optical variable printing apparatus 10 according to a specific embodiment of this application includes a conveying unit 100, a screen printing unit 110, a magnetized roller 130, a magnetic orientation component 132, a pre-drying curing unit 160, and an optical mask curing device 230. A sheet substrate is conveyed to the screen printing unit 110 via the conveying unit 100, where ink or varnish carrier is imprinted onto the sheet substrate through screen printing to form a print 500. The print 500 is conveyed to the magnetized roller 130 via a conveying roller. While the ink or varnish carrier on the print 500 is magnetized and positioned, a pattern formed by a variable light field emitted by the optical mask curing device 230 of the pre-drying curing unit 160, which is positioned opposite the magnetized roller 130, can precisely and variablely pre-dry and cure a portion of the magnetized ink or varnish carrier. To increase the pre-drying and curing time, the pattern of the variable light field must move synchronously with the print 500. Since the pre-drying curing unit 160 is fixed, the pattern needs to be movable within the projection area. Due to the limitation of the projection area, the image of the variable light field can initially be partial, then a complete image, and then a partial image, depending on the rotation direction. After the substrate is magnetized and pre-dried and cured two or more times, it is conveyed by a transfer roller to the drying and curing unit 370 for drying and curing to form the printed material.

[0087] Specifically, such as Figure 8 , Figure 9 , Figure 10 and Figure 11 As shown, taking the synchronously projected image "0" as an example, the image "0" is precisely cured within the printing ink area 510. The substrate 500 moves continuously with the magnetized roller 130. The printing ink area 510 on the substrate 500 is synchronously and continuously magnetized by the magnetic orientation component 132 below it. When the printing ink area 510 enters the projection area, the optical mask curing device 230 starts projection, and the projected image "0" moves synchronously with the substrate 500. When the printing ink area 510 leaves the projection area, the projection, magnetic orientation, and curing of the entire image "0" are completed.

[0088] In summary, the beneficial effects of the embodiments of this application are as follows:

[0089] 1. A series structure of two or more sets of magnetized rollers and pre-drying curing units, which can realize two or more magnetization positioning and pre-curing drying for the same screen-printed graphic;

[0090] 2. Precision variable pre-drying technology: The specially designed pre-drying curing unit with an optical mask curing device can emit a variable light field. The image formed by the variable light field is irradiated onto the substrate on the magnetized roller, and the ink or varnish on the substrate is pre-dried.

[0091] 3. Dual-color optical variable graphic splicing technology: Two suitable magnetic field generating devices are designed to complete the omnidirectional splicing of fixed and variable dual-color optical variable graphics.

[0092] 4. Fixed graphics and text can be circular, rectangular, or diagonal; variable graphics and text can be numbers, serial numbers, barcodes, QR codes, or any other graphics and text.

[0093] 5. The variable light field pattern emitted by the pre-drying curing unit is highly dynamic and refreshed. The refresh rate of the variable light field pattern can be matched with the speed of the magnetized roller. The variable light field pattern irradiated on the substrate can move synchronously with the substrate to increase the curing time.

[0094] 6. A DLP optical engine based on a DMD chip is used as an optical mask curing device to pre-dry and cure inks or varnishes. LED light sources and laser light sources can be used as the light source.

[0095] The technical solution of the present invention has been described in detail above with reference to the accompanying drawings. Through the technical solution of the present invention, a multi-color optical variable technology with multiple effects is realized for the same screen printing pattern, and an omnidirectional splicing technology for multiple effect patterns is realized.

[0096] In this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0097] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0098] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A multi-color optical variable printing device, characterized in that, include: The conveying unit (100) is used to convey the printing substrate; A screen printing unit (110) is used to print ink or varnish containing magnetic material on the substrate; as well as Multiple optically variable pattern forming units, each configured to form an optically variable pattern in a different area of ​​the substrate, each comprising: A magnetized roller (130) is provided with a magnetic orientation member, the magnetic orientation member being used to magnetically orient the substrate; and A pre-drying curing unit (160) is used to pre-dry and cure the substrate; The conveying unit (100), the screen printing unit (110), and the plurality of optically variable pattern forming units are arranged sequentially in the conveying direction of the substrate; In this embodiment, at least two of the optically variable pattern forming units have magnetically oriented components with different magnetization effects. The pre-drying curing unit (160) is positioned opposite to the magnetically oriented component on its outer side. During the magnetic orientation process of the magnetically oriented component on the substrate, the pre-drying curing unit (160) simultaneously pre-dries and cures the substrate. The pre-drying curing unit (160) includes multiple optical mask curing devices (230). The optical mask curing devices (230) are fixedly installed and used to project dynamic and refreshable variable light field images. The variable light field images move synchronously with the substrate by a predetermined distance. The variable light field images move synchronously with the substrate, thereby realizing two or more magnetization positioning and pre-curing drying for the same screen-printed image, and completing the omnidirectional splicing of fixed and variable multi-color optical variable images. The variable light field images emitted by the pre-drying curing unit (160) are highly dynamic and refreshed. The refresh rate of the variable light field images is matched with the speed of the magnetizing roller (130). The variable light field images irradiated on the substrate move synchronously with the substrate, increasing the curing time. The multi-color optical variable printing device includes a sensor, which is used to collect the position information and speed information of the substrate; The optical mask curing device (230) includes: The controller (234) is used to receive the position information and the speed information of the sensor. The controller (234) is also used to receive, store, and process the projection graphic data, and generate a control signal based on the position information, the speed information and the projection graphic data. Light source (232), lens (236), and spatial light modulator (238); The spatial light modulator (238) is used to receive the light emitted by the light source (232) and the control signal, so as to project the variable light field pattern through the lens (236); The pre-drying and curing unit (160) also includes: The curing device adjustment mechanism includes a fixed crossbeam (210), a motor (220), and a guide rail; The fixed crossbeam (210) includes a horizontal plate and a vertical plate, which are connected together. The motor (220) is mounted on the horizontal plate. The guide rail includes a linear guide rail (250) and a curing device guide rail. The linear guide rail (250) is mounted on the horizontal plate, and the curing device guide rail is mounted on the vertical plate. Multiple optical mask curing devices (230) are respectively connected to the linear guide rail (250). The spatial light modulator (238) includes one of the following: a digital micromirror (DMD), a liquid crystal spatial light modulator, and an acousto-optic modulator; The optical mask curing device (230) further includes a heat dissipation component (240) for dissipating heat from the spatial light modulator (238) and / or the light source (232); By adjusting the synchronization control parameters, the variable light field image projected by the optical mask curing device is aligned with the existing printed pattern on the substrate.

2. The multi-color optical variable printing apparatus according to claim 1, characterized in that, The light source (232) includes a UV-LED light source or a laser light source, and the wavelength of the light emitted by the light source (232) is 350nm~425nm.

3. The multi-color optical variable printing apparatus according to claim 2, characterized in that, The variable light field graphics include one of the following: graphics, text, numbers, barcodes, and QR codes.

4. The multi-color optical variable printing apparatus according to any one of claims 1 to 3, characterized in that, Multiple optical mask curing devices (230) are spaced apart in the axial direction of the magnetized roller (130).

5. The multi-color optical variable printing apparatus according to any one of claims 1 to 3, characterized in that, The fixed crossbeam (210) extends along the axial direction of the magnetized roller (130), the optical mask curing device (230) is disposed on the fixed crossbeam (210), and the motor (220) drives the optical mask curing device (230) to move along the fixed crossbeam (210).

6. The multi-color optical variable printing apparatus according to any one of claims 1 to 3, characterized in that, The multi-color optical variable printing apparatus also includes: A transfer system (380) comprising a plurality of transfer rollers for transferring the substrate.

7. The multi-color optical variable printing apparatus according to any one of claims 1 to 3, characterized in that, The multi-color optical variable printing apparatus also includes: The first rearrangement magnetization device (280) is disposed between the screen printing unit (110) and the optically variable pattern forming unit; The second rearrangement magnetization device (290) is disposed between the plurality of the optically variable pattern forming units.

8. The multi-color optical variable printing apparatus according to any one of claims 1 to 3, characterized in that, The ink or the varnish includes photochromic ink or cured varnish.

9. The multi-color optical variable printing apparatus according to any one of claims 1 to 3, characterized in that, The printing substrate includes one of the following: paper, plastic sheet, and metal sheet.

10. The multi-color optical variable printing apparatus according to any one of claims 1 to 3, characterized in that, The multi-color optical variable printing apparatus further includes a drying and curing unit (370), which is located downstream of the plurality of optical variable pattern forming units and is used to dry and cure the substrate.

11. A multi-color optical variable printing method, characterized in that, include: Semi-finished products are formed by printing ink or varnish containing magnetic substances onto a substrate through a screen printing unit. The semi-finished product is sequentially fed to multiple optically variable pattern forming units. The semi-finished product is magnetically oriented and pre-dried and cured by the magnetic orientation component and pre-drying curing unit of the optically variable pattern forming unit, so as to form optically variable patterns in different areas of the substrate, thereby forming a multi-color optically variable product. In this system, at least two of the optically variable pattern forming units have magnetic orientation components with different magnetization effects. The pre-drying curing unit includes an optical mask curing device, which is fixedly installed and used to project dynamically refreshable variable light field images. The variable light field images move synchronously with the substrate by a predetermined distance, thereby achieving two or more magnetization positioning and pre-curing drying for the same screen-printed image. This completes the omnidirectional splicing of fixed and variable multi-color optically variable images. The variable light field images emitted by the pre-drying curing unit are highly dynamically refreshed, and the refresh rate of the variable light field images is matched with the speed of the magnetizing roller. The variable light field images irradiated on the substrate move synchronously with the substrate, increasing the curing time. The controller is used to receive the position information and speed information of the semi-finished product collected by the sensor. The controller is also used to receive, store, and process the projection graphic data, and generate control signals based on the position information, the speed information, and the projection graphic data. The optical mask curing device includes a light source, a lens, and a spatial light modulator; The spatial light modulator is used to receive the light emitted by the light source and the control signal, so as to project the variable light field pattern through the lens; The pre-drying and curing device also includes: A curing device adjustment mechanism, comprising a fixed crossbeam, a motor, and a guide rail; The fixed beam includes a horizontal plate and a vertical plate, which are connected together. The motor is mounted on the horizontal plate. The guide rail includes a linear guide rail and a curing device guide rail. The linear guide rail is mounted on the horizontal plate, and the curing device guide rail is mounted on the vertical plate. Multiple optical mask curing devices are respectively connected to the linear guide rail. The optical mask curing device further includes a heat dissipation component, which is used to dissipate heat from the spatial light modulator and / or the light source; The spatial light modulator includes one of the following: a digital micromirror (DMD), a liquid crystal spatial light modulator, and an acousto-optic modulator; By adjusting the synchronization control parameters, the variable light field image projected by the optical mask curing device is aligned with the existing printed pattern on the substrate.

12. The multi-color optical variable printing method according to claim 11, characterized in that, The multi-color optical variable printing method further includes: After the semi-finished product is sequentially conveyed to multiple optically variable pattern forming units, the multi-optically variable product is conveyed to a drying and curing unit for drying and curing.

13. A multi-color optical variable printing apparatus, characterized in that, include: A memory (300) and a processor (400), wherein the memory (300) stores a program or instructions that can run on the processor (400), and the processor (400) executes the program or instructions to implement the steps of the multicolor optical variable printing method as described in claim 11 or 12.

14. A readable storage medium having a program or instructions stored thereon, characterized in that, When the program or the instructions are executed by the processor, they implement the steps of the multi-color optical variable printing method as described in claim 11 or 12.

Images