Overprinting device and overprinting method for flexible packaging

Abstract

The invention discloses an overprinting device and method for flexible packaging in the technical field of printing, and aims to solve the problems that in the prior art, due to the fact that a flexible packaging plate is printed firstly and then subjected to auxiliary processing, product overprinting is inaccurate, and the process is tedious. The device comprises a conveying line, a plurality of registration printing assemblies are arranged on the conveying line, each registration printing assembly comprises a support and a printing roller rotationally arranged on the support, the support is further provided with a first driving assembly used for driving the printing roller to rotate, and the printing roller is provided with an ink printing area and a mark stamping area. Each support is provided with an ink supply assembly, and the ink supply assemblies are used for supplying ink to an ink printing area. The method is used for achieving efficient printing of the packaging product and manufacturing of the anti-fake technology, optimization of the packaging product technology can be achieved without adopting extra complex equipment, the overprinting accuracy of the auxiliary technology can be effectively guaranteed, and therefore the product yield can be effectively increased.

Description

Technical Field

[0001] This invention relates to an overprinting device and method for flexible packaging, belonging to the field of printing technology. Background Technology

[0002] Currently, to enhance product added value and market appeal, brands often design and implement various post-processing techniques on flexible packaging surfaces, such as embossing, texturing, anti-counterfeiting, and Braille. In existing technologies, these post-processing techniques all need to be completed step-by-step on separate, dedicated equipment, which not only increases equipment investment, energy consumption, and labor costs, but also extends the production cycle.

[0003] In addition, the base paper is prone to differential shrinkage after printing and drying. This shrinkage characteristic has a great impact on the registration accuracy of the fine and complex processes after printing, which significantly increases the registration difficulty of the subsequent processing steps, further increasing production costs and the defect rate. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide an overprinting device and method for flexible packaging, which can realize efficient printing of packaging products and the production of anti-counterfeiting technology. It can optimize the packaging product process without the need for additional complex equipment and can effectively ensure the overprinting accuracy of auxiliary processes, thereby effectively improving product yield.

[0005] To achieve the above objectives, the present invention employs the following technical solution: On one hand, the present invention provides a registration printing device for flexible packaging, including a conveyor line, wherein a plurality of registration printing components are arranged on the conveyor line, each registration printing component includes a bracket and a printing roller rotatably arranged on the bracket, and a first driving component for driving the printing roller to rotate is also provided on the bracket, the printing roller is provided with an ink printing area and a marking imprinting area, and each bracket is provided with an ink supply component for supplying ink to the ink printing area.

[0006] Specifically, the registration printing assembly is provided in three sets. The marking and imprinting areas of the three printing rollers of the three sets of registration printing assemblies are respectively set as anti-counterfeiting pattern imprinting areas, embossing areas, and raised imprinting areas. The support on which the printing roller marked with the raised imprinting area is located is also provided with a cooperating roller. The cooperating roller and the printing roller at this position are respectively provided with a positive plate and a negative plate that can cooperate. The cooperating roller and the printing roller at this position rotate synchronously relative to each other so that the flexible packaging board located between them can form raised markings.

[0007] Specifically, the three printing rollers containing the anti-counterfeiting pattern embossing area, the texture embossing area, and the raised embossing area are arranged sequentially according to the conveying direction of the conveyor line. The conveyor line is set in two sets according to the conveying direction. The matching roller is located between the two sets of conveyor lines. The gap between the matching roller and the printing roller opposite it is located at the conveying plane of the conveyor line.

[0008] Specifically, mounting frames are respectively provided on the conveyor lines located on both sides of the mating roller. An auxiliary guide roller is rotatably mounted on each of the two mounting frames. A second drive assembly for driving the auxiliary guide roller to rotate is provided on each of the two mounting frames. The auxiliary guide roller is used to transmit the flexible packaging board on the surface of the conveyor line from the gap between the mating roller and its corresponding printing roller.

[0009] Specifically, the auxiliary rollers are two coaxially connected, oppositely arranged discs, and the auxiliary rollers act on both sides of the flexible packaging board.

[0010] Specifically, a heat insulation cover is installed on the conveyor line downstream of the mating roller. The heat insulation cover is equipped with a hot air blowing component for drying the surface of the flexible packaging board. An exhaust pipe for treating exhaust gas is also connected to the heat insulation cover.

[0011] Specifically, the hot air blowing assembly includes a main air inlet pipe installed inside the heat insulation cover, and multiple branch air blowing pipes are connected to the main air inlet pipe. A heating element is installed between two adjacent sets of branch air blowing pipes.

[0012] Specifically, the heat insulation cover is equipped with an ultraviolet curing device inside.

[0013] On the other hand, the present invention provides an overprinting method for flexible packaging, employing the aforementioned overprinting device for flexible packaging, the method comprising the following steps: The flexible packaging board to be printed is placed on the conveyor line, and three sets of printing rollers on the conveyor line print the three primary colors on the flexible packaging board, wherein: When printing the first primary color, the anti-counterfeiting pattern is simultaneously imprinted on the flexible packaging board by the anti-counterfeiting pattern imprinting area of ​​the corresponding printing roller. The anti-counterfeiting pattern includes, but is not limited to, anti-counterfeiting blank stripes and blank flower patterns. When printing the second primary color, the embossing area of ​​the corresponding printing roller simultaneously imprints the anti-counterfeiting background on the flexible packaging board. When printing the third primary color, the corresponding printing roller and its matching roller simultaneously process the concave and convex structure of the flexible packaging board surface.

[0014] Specifically, the method also includes: rapidly drying the surface of the flexible packaging board after the three primary colors printing is completed.

[0015] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: This invention leaves a marking and imprinting area directly on the printing roller used for printed packaging products. This allows the marking and imprinting to be left simultaneously in the corresponding printing area during the printing process. This avoids the problem of inaccurate registration and poor imprinting caused by post-printing reprocessing. In this method, not only can the positional accuracy of the auxiliary processing be well guaranteed, but it can also help to reduce the setting of other auxiliary imprinting equipment, thereby reducing the complexity of the process and the cost of equipment configuration, thus achieving efficient and high-precision production. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of an overprinting device provided in an embodiment of the present invention; Figure 2 This is the present invention. Figure 1 An enlarged view of the structure at point A of an overprinting device provided in the embodiment; Figure 3 This is a side view of an overlay device provided in an embodiment of the present invention; Figure 4 This is the present invention. Figure 3 A cross-sectional view of an overlay apparatus in the BB direction provided in the embodiment; Figure 5 This is the present invention. Figure 4 An enlarged view of the structure at point C of an overprinting device provided in the embodiment; Reference numerals: 1. Conveyor line; 2. Support frame; 3. Printing roller; 4. First drive assembly; 5. Matching roller; 6. Mounting frame; 7. Auxiliary passing roller; 8. Second drive assembly; 9. Adjustment mechanism; 10. Insulation cover; 11. Main air inlet pipe; 12. Branch air blowing pipe; 13. Heating component; 14. Ultraviolet curing device; 15. Exhaust pipe; 16. Adsorption plate assembly. Detailed Implementation

[0017] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0018] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0019] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances. Example 1

[0020] This invention provides a printing device for flexible packaging, which enables efficient printing and anti-counterfeiting processes on packaging products. It optimizes packaging processes without requiring additional complex equipment and effectively ensures the accuracy of registration in auxiliary processes, thereby improving product yield. To achieve the device's structural functions, it includes a conveyor line 1 with several registration printing components. Each registration printing component includes a support 2 and a printing roller 3 rotatably mounted on the support 2. The printing roller 3 is used for color printing on the surface of the flexible packaging board. For this purpose, the support 2 also has a first driving component 4 for driving the printing roller 3 to rotate. The first driving component 4 can be driven by a servo motor to ensure rotation speed and accuracy. To efficiently perform auxiliary processing on the cardboard, an ink printing area is directly provided on the printing roller 3. The labeling and embossing area includes an ink printing area for printing color patterns on the flexible packaging board. Each support 2 should be equipped with an ink supply component to supply ink to the ink printing area. For the labeling and embossing area, an appropriate auxiliary processing method should be selected according to the type of label. The types of labels should include, but are not limited to, embossing, texturing, anti-counterfeiting, and Braille. For embossing, texturing, and Braille, a corresponding embossed structure should be provided in the labeling and embossing area to act on the flexible packaging board. For anti-counterfeiting labels, such as barcodes and high-precision complex patterns, a blank method can be used for embossing. For color anti-counterfeiting patterns that require additional ink, anti-counterfeiting can be achieved by supplying different forms of ink to the labeling and embossing area. The specific supply method is not limited here, and different ink supply rollers can be used to supply ink to the embossing area.

[0021] This invention provides a printing device for flexible packaging. To ensure the production quality of flexible packaging products, three sets of registration printing components are configured. Specifically, the marking and imprinting areas of the three printing rollers 3 of the three sets of registration printing components are respectively set as an anti-counterfeiting pattern imprinting area, an embossed imprinting area (which can be printed separately with materials that have obvious concavity and convexity, such as by controlling the ink thickness in this area), and a raised imprinting area. In order to make the concavity and convexity of the raised area more obvious, its position can be determined by referring to... Figure 4As shown, a mating roller 5 is also provided on the support 2 where the printing roller 3, marked with the embossing area, is located. At this position, the mating roller 5 and the printing roller 3 are respectively provided with mating positive and negative plates. The mating roller 5 and the printing roller 3 rotate synchronously relative to each other so that the flexible packaging board located between them can form embossed markings (the synchronous relative rotation can be achieved by setting meshing gears with a transmission ratio of 1:1 on the shafts of the two rollers; other implementation methods are not limited here). The flexible packaging board, conveyed by the conveyor line 1, forms a distinct embossed structure by embossing after passing through the gap between the two rollers. This allows for synchronous completion of embossing operations at corresponding positions during printing. Similarly, the printing rollers 3 at other positions can directly emboss the corresponding markings in the corresponding areas when printing the corresponding colors. This effectively improves the accuracy of the mating positions in auxiliary processing and avoids paper deformation due to thermal expansion and contraction, thus reducing the complexity of the process while ensuring the accuracy of printing and auxiliary processes, ensuring efficient and high-precision production of flexible packaging boards.

[0022] This invention provides a printing device for flexible packaging. Considering that the thickness and texture of the flexible packaging board surface may affect normal color printing, the parts of the flexible packaging board with large structural deformation should be placed at the end of the process. Therefore, three printing rollers 3 containing anti-counterfeiting pattern imprinting area, embossing area, and raised imprinting area can be arranged sequentially according to the conveying direction of the conveyor line 1. To ensure that the flexible packaging board can be smoothly conveyed during the raised imprinting process, the conveyor line 1 can be configured with two sets according to the conveying direction. (Referring to...) Figure 4 As shown, the mating roller 5 is positioned between the two sets of conveyor lines 1. Simultaneously, the gap between the mating roller 5 and its opposite printing roller 3 is positioned at the conveying plane of the conveyor line 1. This ensures that the flexible packaging board is stably supported during conveying on the conveyor line 1 and can orderly enter the gap between the mating roller 5 and the printing roller 3, ensuring stable embossing processing. In some other embodiments, to ensure the stability of the cardboard conveying process, a corresponding adsorption plate assembly 16 can be configured inside the conveyor line 1. This adsorption plate assembly 16 is fitted against the lower surface of the upper conveyor belt. Correspondingly, adsorption holes need to be provided on the conveyor belt above the adsorption plate assembly 16, allowing the adsorption plate assembly 16 to provide negative pressure to the adsorption holes, ensuring stable adsorption and conveying of the printed flexible packaging board product.

[0023] This invention provides an overprinting device for flexible packaging. To prevent the flexible packaging board from being obstructed before and after entering the embossing process, causing it to shift relative to the printing position and affecting accurate printing, mounting frames 6 are respectively provided on the conveyor lines 1 located on both sides of the mating roller 5. Specifically, auxiliary guide rollers 7 are rotatably mounted on both mounting frames 6. At this time, a second drive assembly 8 for driving the auxiliary guide rollers 7 to rotate is provided on both mounting frames 6. The second drive assembly 8 can also be a servo motor, thereby achieving precise control and transmission. The auxiliary guide rollers 7 are used to transmit the flexible packaging board on the surface of the conveyor line 1 from the gap between the mating roller 5 and its corresponding printing roller 3. By providing an upper limit to ensure the conveying direction of the flexible packaging board, and combining with the belt above the lower conveyor line 1 to form a clamping conveyor, it is ensured that the flexible packaging board can be accurately moved to the embossing processing station, ensuring stable processing and printing of the product.

[0024] This invention provides a printing apparatus for flexible packaging. To reduce ink adhesion to the auxiliary roller 7 and thus reduce its impact on product color accuracy, the auxiliary roller 7 can be configured as two coaxially connected, oppositely arranged discs. (Refer to...) Figure 2 As shown, the auxiliary roller 7 operates on both sides of the flexible packaging board, which can avoid the printing area to clamp the flexible packaging board, or minimize the contact area with the printing area, thereby reducing the impact of printing interference. In some other embodiments, an adjustment mechanism 9 for adjusting the height of the auxiliary roller 7 can be provided on the mounting frame 6, so that the surface height of the auxiliary roller 7 above the conveyor line 1 can be controlled according to the thickness of different products.

[0025] This invention provides an overprinting device for flexible packaging. In some other embodiments, considering the need for rapid drying of ink after printing to avoid color contamination, a heat insulation cover 10 can be installed on the conveyor line 1 downstream of the mating roller 5. A hot air blowing assembly for drying the surface of the flexible packaging board is installed inside the heat insulation cover 10, thereby achieving rapid ink drying. For the undesirable waste gas generated during the drying process, a waste gas pipe 15 can be connected to the heat insulation cover 10 for secondary processing. By placing the hot air blowing assembly at the rear end of the conveyor line 1, that is, after completing auxiliary processing such as embossing, drying is performed. Compared to the traditional method of drying the ink first and then embossing, this method avoids the peeling of the ink curing layer structure caused by deformation during the embossing process, thus preventing damage to the cured ink layer after printing and avoiding product defects due to process problems.

[0026] This invention provides a printing device for flexible packaging, specifically offering a configuration of a hot air blowing assembly. Specifically, the hot air blowing assembly includes a main air inlet pipe 11 installed inside a heat insulation cover 10. Multiple branch air blowing pipes 12 are connected to the main air inlet pipe 11 and spaced apart from each other. A heating element 13 is positioned between adjacent sets of branch air blowing pipes 12. This configuration, compared to the traditional method of directly supplying hot air, allows the heating element 13 (such as a heating wire) to radiate heat into the heat insulation cover 10, raising the overall temperature inside the heat insulation cover 10. The branch air blowing pipes 12 are positioned close to the heating element 13 to directly blow the heat emitted by the heating element 13 onto the surface of the printed material. This allows the flexible packaging material to directly enter a higher temperature environment after entering the heat insulation cover 10, where it can then be quickly dried by the hot air, avoiding heat loss caused by the complex piping of traditional hot air methods.

[0027] In some other embodiments of the present invention, considering that anti-counterfeiting marks or embossed marks may be achieved by UV-sensitive ink or UV adhesive printing, a UV curing device 14 can be provided inside the heat insulation cover 10 to achieve rapid curing of the UV adhesive material. Example 2

[0028] This invention provides a method for overprinting flexible packaging, employing any of the flexible packaging overprinting devices described in Embodiment 1. This method allows for direct auxiliary processing of the flexible packaging board during the printing process, improving product quality while ensuring high-precision and high-efficiency manufacturing. The processing method includes the following steps: The flexible packaging board to be printed is placed on conveyor line 1, and the three primary colors are printed on the flexible packaging board by three sets of printing rollers 3 on conveyor line 1, wherein: When printing the first primary color, the anti-counterfeiting pattern is simultaneously imprinted on the flexible packaging board by the anti-counterfeiting pattern imprinting area of ​​the corresponding printing roller 3. The anti-counterfeiting pattern includes, but is not limited to, anti-counterfeiting blank stripes and blank flower patterns. When printing the second primary color, the anti-counterfeiting background pattern is simultaneously imprinted on the flexible packaging board by the embossing area of ​​the corresponding printing roller 3. When printing the third primary color, the corresponding printing roller 3 and its cooperating roller 5 simultaneously process the concave and convex structure of the flexible packaging board surface.

[0029] Using the above method, flexible packaging board products with embossed deformation, texture, and anti-counterfeiting marks can be obtained directly after the color pattern (three primary color pattern) is printed. Compared with the traditional method of printing first and then performing local registration processing, it can effectively avoid the complexity of registration and the problem of inaccurate registration position caused by paper deformation. It simplifies the processing operation and can effectively improve processing efficiency and processing accuracy while reducing processing costs.

[0030] This invention provides a method for overprinting flexible packaging. Considering that the traditional method of drying ink before processing may damage the cured ink during auxiliary processing, thus affecting the product's molding quality, the method can be configured to further include: rapidly drying the surface of the flexible packaging board after the three primary colors are printed. Compared to the traditional method of drying ink before other processes, this method can achieve ink curing after processes such as embossing and texturing, which can effectively avoid damage to the ink curing structure layer caused by deformation of the packaging paperboard, thereby helping to ensure product yield and anti-counterfeiting quality.

[0031] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A printing device for flexible packaging, characterized in that, The system includes a conveyor line (1), on which several registration printing components are provided. Each registration printing component includes a support (2) and a printing roller (3) rotatably mounted on the support (2). The support (2) is also provided with a first drive component (4) for driving the printing roller (3) to rotate. The printing roller (3) is provided with an ink printing area and a marking imprinting area. Each support (2) is provided with an ink supply component for supplying ink to the ink printing area.

2. The overprinting device for flexible packaging according to claim 1, characterized in that, The registration printing assembly is provided in three sets. The marking and imprinting areas of the three printing rollers (3) of the three sets of registration printing assemblies are respectively set as anti-counterfeiting pattern imprinting area, embossing area and raised imprinting area. The support (2) on which the printing roller (3) marked with raised imprinting area is located is also provided with a cooperating roller (5). The cooperating roller (5) and the printing roller (3) at this position are respectively provided with a positive plate and a negative plate that can cooperate. The cooperating roller (5) and the printing roller (3) at this position rotate synchronously relative to each other so that the flexible packaging plate located between them can form raised markings.

3. The overprinting device for flexible packaging according to claim 2, characterized in that, Three printing rollers (3) containing anti-counterfeiting pattern embossing area, embossing area and raised embossing area are arranged in sequence according to the conveying direction of the conveying line (1). The conveying line (1) is set in two sets according to the conveying direction. The matching roller (5) is set between the two sets of conveying lines (1). The gap between the matching roller (5) and the printing roller (3) opposite it is located at the conveying plane of the conveying line (1).

4. The overprinting device for flexible packaging according to claim 3, characterized in that, Mounting frames (6) are respectively provided on the conveyor lines (1) on both sides of the mating roller (5). An auxiliary roller (7) is rotatably provided on each of the two mounting frames (6). A second driving assembly (8) for driving the auxiliary roller (7) to rotate is provided on each of the two mounting frames (6). The auxiliary roller (7) is used to transmit the flexible packaging board on the surface of the conveyor line (1) from the gap between the mating roller (5) and its corresponding printing roller (3).

5. The overprinting device for flexible packaging according to claim 4, characterized in that, The auxiliary rollers (7) are two coaxially connected, oppositely arranged discs, and the auxiliary rollers (7) act on both sides of the flexible packaging board.

6. The overprinting device for flexible packaging according to claim 3, characterized in that, A heat insulation cover (10) is provided on the conveyor line (1) located downstream of the mating roller (5). The heat insulation cover (10) is equipped with a hot air blowing assembly for drying the surface of the flexible packaging board. The heat insulation cover (10) is also connected to an exhaust pipe (15) for treating exhaust gas.

7. The overprinting device for flexible packaging according to claim 6, characterized in that, The hot air blowing assembly includes a main air inlet pipe (11) installed inside the heat insulation cover (10), and multiple branch air blowing pipes (12) are connected to the main air inlet pipe (11). A heating element (13) is provided between two adjacent sets of branch air blowing pipes (12).

8. The overprinting device for flexible packaging according to claim 7, characterized in that, The heat insulation cover (10) is equipped with an ultraviolet curing device (14).

9. A method for overprinting flexible packaging, characterized in that, The method using the flexible packaging overprinting apparatus as described in any one of claims 2-8 includes the following steps: The flexible packaging board to be printed is placed on the conveyor line (1), and the three primary colors are printed on the flexible packaging board by three sets of printing rollers (3) on the conveyor line (1), wherein: When printing the first primary color, the anti-counterfeiting pattern is simultaneously imprinted on the flexible packaging board by the anti-counterfeiting pattern imprinting area of ​​the corresponding printing roller (3). The anti-counterfeiting pattern includes, but is not limited to, anti-counterfeiting blank stripes and blank flower patterns. When printing the second primary color, the anti-counterfeiting background pattern is simultaneously printed on the flexible packaging board by the embossing area of ​​the corresponding printing roller (3). When printing the third primary color, the corresponding printing roller (3) and its matching roller (5) simultaneously process the concave and convex structure of the flexible packaging board surface.

10. A method for overprinting for flexible packaging according to claim 9, characterized in that, The method also includes: rapidly drying the surface of the flexible packaging board after the three primary colors printing is completed.

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