A plate-less three-dimensional cold stamping method

Abstract

The present invention provides a plate - less three - dimensional cold stamping method, which includes installing a printing material and a cold stamping film on a plate - less three - dimensional cold stamping device; bringing the cold stamping film into contact with the UV adhesive in a printing dish; outputting a pattern to be stamped to a liquid crystal screen; curing the UV adhesive on the cold stamping film to form an adhesive area consistent with the stamped pattern; passing the dried cold stamping film through between the printing material and a laminating roller, and firmly bonding the adhesive area of the cold stamping film to the surface of the printing material by applying pressure, so that the stamped pattern is completely transferred to the surface of the printing material. In the present invention, the adhesive area with the stamped pattern can be completed without plate - making. It displays the stamped pattern through a high - resolution liquid crystal screen illuminated by an ultraviolet light source, and can directly cure to form an adhesive pattern on the cold stamping film, saving the plate - making cycle and cost of traditional stamping, solving the problem of rapid stamping of personalized patterns, and having low cost, high stamping accuracy, and can also achieve a real three - dimensional stamping effect.

Description

Technical Field

[0001] The present invention belongs to the field of printing equipment, and particularly relates to a plate-free three-dimensional cold stamping method. Background Art

[0002] As a part of product packaging, unique and aesthetic printing and decoration effects help to attract customers' attention and become an important means to increase the value of packaging products. Among them, the environmentally friendly stamping process has received increasing attention. Stamping is divided into hot stamping and cold stamping. In the hot stamping process, the back of the hot stamping foil is coated with a hot melt adhesive, and during stamping, the adhesive is melted by the pressure of the hot roller to achieve the transfer of the aluminum foil. Cold stamping uses special hot stamping foil, the back of which is not coated with glue, and the adhesive is directly applied to the position to be decorated during printing, and a new cold pressing technology is used to transfer the hot stamping foil. The cold stamping technology solves the process problems difficult to solve in hot stamping printing, avoids the environmental pollution caused during the production of metal printing plates, and can also save a large amount of energy. However, the traditional cold stamping method has some deficiencies: First, it still requires pre-making a mold plate for printing ultraviolet (UV) adhesive, with a long plate-making cycle and cannot meet the rapid stamping of personalized graphics; second, the stamping accuracy is limited by the mold plate-making accuracy, and it is difficult to print graphics with high precision. The printing accuracy of the thinnest line is generally greater than 0.06 mm; third, the three-dimensional stamping effect is limited, and it is impossible to print three-dimensional graphics with a large height of more than 0.5 mm or non-uniform height. Summary of the Invention

[0003] Aiming at the above deficiencies of the prior art, the present invention provides a plate-free three-dimensional cold stamping method with high precision, high speed and low cost.

[0004] The present invention is realized through the following technical solutions:

[0005] A plate-free three-dimensional cold stamping method includes the following steps:

[0006] (1) Install the printing material and the cold stamping film on the plate-free three-dimensional cold stamping device; that is, install the printing material on the conveying unit and adjacent to the laminating roller; pull out the cold stamping film from the unwinding mechanism, pass it around the first conveying roller and the second conveying roller in sequence, then pass through between the printing material and the laminating roller, and finally fix it on the waste recycling mechanism for winding.

[0007] The plate - less three - dimensional cold stamping device includes a conveying unit, a winding and unwinding unit, a stamping unit, and a light - curing graphics unit; the conveying unit is used to continuously or intermittently convey the printing material forward; the winding and unwinding unit is used to continuously or intermittently convey the cold stamping film forward, and it includes an unwinding mechanism, a first conveying roller, a second conveying roller, and a waste recycling mechanism; the stamping unit includes a laminating pressure roller which is rotatably arranged in the mounting frame; the light - curing graphics unit includes a workbench with a cavity inside and an opening at the upper end. A UV curing light source is arranged in the cavity of the workbench. At the upper - end opening of the workbench, a planar Fresnel lens, a liquid crystal screen, and a light - transmissive release film are arranged in sequence from bottom to top. The light - transmissive release film is required to transmit UV light. Above the light - transmissive release film, there is a printing dish for containing UV adhesive, and the bottom of the printing dish is required to transmit UV light; the liquid crystal screen is used to display the required stamping graphics, and the display mode of the liquid crystal screen is negative display, that is, the displayed part is light - transmissive and the non - displayed part is non - light - transmissive;

[0008] (2) Adjust the relative positions of the first conveying roller and the second conveying roller with respect to the workbench so that both the first conveying roller and the second conveying roller are inside the printing dish, and the cold stamping film between the first conveying roller and the second conveying roller is in contact with the UV adhesive in the printing dish;

[0009] (3) Output the graphics to be stamped to the liquid crystal screen, that is, a situation where part is light - transmissive and part is non - light - transmissive appears on the liquid crystal screen, and the graphics formed by the light - transmissive part are the graphics to be stamped;

[0010] (4) Start the UV curing light source so that the UV curing light source emits UV rays. The UV rays pass through the planar Fresnel lens, the liquid crystal screen, and the light - transmissive release film in sequence and irradiate on the UV adhesive, causing the UV adhesive to cure on the cold stamping film to form an adhesive area consistent with the stamping graphics;

[0011] (5) Start the winding and unwinding unit to convey the cold stamping film forward, that is, move the cold stamping film with the adhesive area out of the printing dish. Then, remove the uncured UV adhesive on the cold stamping film through a rinsing device, and remove the moisture in the adhesive area through a drying device;

[0012] (6) The cold stamping film with the adhesive area after drying passes through between the printing material and the laminating pressure roller, and the adhesive area on the cold stamping film contacts the surface of the printing material; control the laminating of the laminating pressure roller and the printing material, and through pressing, the adhesive area of the cold stamping film is firmly bonded to the surface of the printing material. With the movement of the conveying unit and the winding of the cold stamping film, the excess cold stamping film will be peeled off from the printing material, and then the stamping graphics are completely transferred to the surface of the printing material.

[0013] Preferably, in step (4), the contrast of the hot stamping pattern on the LCD screen is adjusted in real time, and the hot stamping patterns with different light and dark distributions are displayed in time-sharing manner, which can change the light and dark degree and light and dark time of the local pixel area, thereby changing the UV light pass rate and exposure time, and realizing the control of the curing speed and curing time of the adhesive areas at different positions on the cold stamping film, thereby realizing a three-dimensional adhesive curing three-dimensional pattern with non-uniform height on the cold stamping film, wherein the curing height is adjustable within the range of 0.05-1mm, and finally transferred to the surface of the printing material, to achieve a real three-dimensional hot stamping effect.

[0014] Preferably, in step (1), the workbench is provided with an integral lifting mechanism for adjusting the height of the workbench, thereby adjusting the interval between the cold stamping film and the light-transmitting release film.

[0015] Preferably, the UV curing light source in step (1) is implemented using an array UV light source.

[0016] Preferably, in step (1), the inner wall surface of the workbench cavity is provided with a reflective film.

[0017] The present invention has the following beneficial effects:

[0018] 1. The adhesive area with the hot stamping pattern in the present invention can be completed without plate making. The hot stamping pattern is displayed by a high-resolution liquid crystal screen illuminated by an ultraviolet (UV) light source, and the adhesive pattern can be directly solidified on the cold stamping film to form an adhesive pattern, thereby eliminating the plate making cycle and cost of traditional hot stamping, solving the problem of rapid hot stamping of personalized patterns, and at a low cost.

[0019] 2. The hot stamping precision of the present invention is very high, and the precision mainly depends on the resolution of the LCD screen, that is, the pixel density ppi, which can reach 500-1000 or more, and the printing precision of the finest line can reach 0.02-0.05mm, which is more precise than the traditional hot stamping process.

[0020] 3. The present invention can flexibly control the brightness and darkness of the local pixel area and the brightness and darkness time, that is, the UV light transmittance and exposure time, by controlling the liquid crystal screen, thereby achieving a real three-dimensional hot stamping effect of large height and non-uniform height at different positions that cannot be achieved by traditional hot stamping methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic structural diagram of the plateless three-dimensional cold stamping device of the present invention. DETAILED DESCRIPTION

[0022] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] like Figure 1As shown in the figure, the present invention provides a plate - less three - dimensional cold stamping device, including a conveying unit, a rewinding and unwinding unit, a stamping unit, and a light - curing graphic unit.

[0024] The conveying unit is used to continuously or intermittently convey the printing material 6 forward. The rewinding and unwinding unit includes an unwinding mechanism 4, a first conveying roller 1, a second conveying roller 2, and a waste recycling mechanism 5. The unwinding mechanism 4, the first conveying roller 1, the second conveying roller 2, and the waste recycling mechanism 5 cooperate to continuously or intermittently convey the cold stamping film 3 forward.

[0025] The stamping unit includes a laminating pressure roller 7 which is rotatably arranged in the mounting frame. The cold stamping film 3 passes between the printing material 6 and the laminating pressure roller 7. When the laminating pressure roller 7 is in contact with the printing material 6, the stamping pattern on the cold stamping film 3 can be transferred to the surface of the printing material 6.

[0026] The light - curing graphic unit includes a workbench 13 with a cavity inside and an opening at the upper end. A UV curing light source 8 is arranged in the cavity of the workbench 13. At the upper - end opening of the workbench 13, a planar Fresnel lens 9, a liquid crystal screen 10, and a light - transmissive release film 11 are arranged in sequence from bottom to top. The light - transmissive release film 11 is required to transmit UV light. Above the light - transmissive release film 11, there is a printing dish 12 for containing UV adhesive, and the bottom of the printing dish 12 is required to transmit UV light. The UV curing light source 8 can be realized by a matrix UV light source. The liquid crystal screen 10 is used to display the required stamping pattern, and the display mode of the liquid crystal screen 10 is negative display, that is, the displayed part is light - transmissive and the non - displayed part is non - light - transmissive, commonly known as a dark background with bright characters. Preferably, the inner wall surface of the cavity is provided with a reflective film to utilize the UV light source more efficiently and improve the light uniformity for illuminating the liquid crystal screen. The workbench 13 can also be provided with an overall lifting mechanism for adjusting the height of the workbench 13, and then the interval between the cold stamping film 3 and the light - transmissive release film 11 can be conveniently adjusted.

[0027] Based on the above - mentioned plate - less three - dimensional cold stamping device, the present invention provides a plate - less three - dimensional cold stamping method, including the following steps:

[0028] (1) Install the printing material 6 and the cold stamping film 3 on the plate - less three - dimensional cold stamping device; that is, install the printing material 6 on the conveying unit and adjacent to the laminating pressure roller 7; pull out the cold stamping film 3 from the unwinding mechanism 4, bypass the first conveying roller 1 and the second conveying roller 2 in sequence, then pass between the printing material 6 and the laminating pressure roller 7, and finally fix it on the waste recycling mechanism 5 for winding.

[0029] (2) Adjust the relative positions of the first conveying roller 1 and the second conveying roller 2 and the workbench 13 so that both the first conveying roller 1 and the second conveying roller 2 are inside the printing dish 12, and the cold stamping film 3 between the first conveying roller 1 and the second conveying roller 2 is in contact with the UV adhesive in the printing dish 12.

[0030] (3) Outputting the pattern to be stamped to the liquid crystal screen 10, that is, the liquid crystal screen 10 appears partially transparent and partially opaque, and the pattern formed by the transparent part is the pattern to be stamped.

[0031] (4) The UV curing light source 8 is started to emit UV light, which passes through the flat Fresnel lens 9, the liquid crystal screen 10 and the light-transmitting release film 11 in sequence and irradiates the UV adhesive, so that the UV adhesive is cured on the cold stamping film 3 to form an adhesive area 14 consistent with the stamping pattern.

[0032] During this process, the contrast of the pattern to be stamped on the LCD screen 10 can be adjusted in real time, and stamped patterns with different light and dark distributions can be displayed in time. This can change the brightness and darkness of the local pixel area and the light and dark time, thereby changing the UV light pass rate and exposure time, and realizing the control of the curing speed and curing time of the adhesive areas at different positions on the cold stamping film 3, thereby realizing a three-dimensional adhesive solidified three-dimensional pattern with non-uniform height on the cold stamping film 3, wherein the curing height is adjustable within the range of 0.05-1mm, and finally transferred to the surface of the printing material 6, so as to realize a real three-dimensional hot stamping effect.

[0033] (5) Start the unwinding and rewinding unit to convey the cold foil film 3 forward, that is, move the cold foil film 3 with the adhesive area 14 out of the printing plate 12, then remove the uncured UV adhesive on the cold foil film 3 through the washing device, and then remove the moisture in the adhesive area 14 through the drying device.

[0034] (6) The dried cold foil film 3 with the adhesive area 14 passes between the printing material 6 and the laminating roller 7, and the adhesive area 14 on the cold foil film 3 contacts the surface of the printing material 6; the laminating roller 7 is controlled to laminarize the printing material 6, and the adhesive area 14 of the cold foil film 3 is firmly adhered to the surface of the printing material 6 by applying pressure. With the movement of the conveying unit and the winding of the cold foil film 3, the excess cold foil film 3 is peeled off from the printing material 6, and the hot stamping pattern is completely transferred to the surface of the printing material 6.

[0035] The present invention can be modified in many ways that are obvious to those skilled in the art, and such modifications are not considered to depart from the scope of the present invention. All such modifications that are obvious to those skilled in the art are intended to be included within the scope of the present claims.

Claims

1. A plate-less three-dimensional cold stamping method, characterized in that, It includes the following steps: (1) Install the printing material (6) and the cold stamping film (3) on the plate - less three - dimensional cold stamping device; that is, install the printing material (6) on the conveying unit and adjacent to the laminating pressure roller (7); pull out the cold stamping film (3) from the unwind mechanism (4), pass it around the first conveying roller (1) and the second conveying roller (2) in sequence, then pass through between the printing material (6) and the laminating pressure roller (7), and finally fix it on the waste recycling mechanism (5) for winding. The plate - less three - dimensional cold stamping device includes a conveying unit, a winding and unwinding unit, a stamping unit, and a light - curing graphic unit; the conveying unit is used to continuously or intermittently convey the printing material (6) forward; the winding and unwinding unit is used to continuously or intermittently convey the cold stamping film (3) forward, and it includes an unwind mechanism (4), a first conveying roller (1), a second conveying roller (2), and a waste recycling mechanism (5); the stamping unit includes a laminating pressure roller (7), and the laminating pressure roller (7) is rotatably arranged in the mounting frame; the light - curing graphic unit includes a workbench (13) with a cavity inside and an opening at the upper end. A UV curing light source (8) is arranged in the cavity of the workbench (13). At the upper - end opening of the workbench (13), a planar Fresnel lens (9), a liquid - crystal screen (10), and a light - transmissive release film (11) are arranged in sequence from bottom to top. The light - transmissive release film (11) is required to transmit UV light. Above the light - transmissive release film (11), a printing dish (12) for containing UV adhesive is arranged, and the bottom of the printing dish (12) is required to transmit UV light; the liquid - crystal screen (10) is used to display the required stamping pattern, and the display mode of the liquid - crystal screen (10) is negative display, that is, the display part is light - transmissive and the non - display part is non - light - transmissive. (2) Adjust the relative positions of the first conveying roller (1) and the second conveying roller (2) and the workbench (13) so that both the first conveying roller (1) and the second conveying roller (2) are inside the printing dish (12), and the cold stamping film (3) between the first conveying roller (1) and the second conveying roller (2) is in contact with the UV adhesive in the printing dish (12). (3) Output the pattern to be stamped to the liquid - crystal screen (10), that is, a situation where part is light - transmissive and part is non - light - transmissive appears on the liquid - crystal screen (10), and the pattern formed by the light - transmissive part is the pattern to be stamped. (4) Start the UV curing light source (8) so that the UV curing light source (8) emits UV light. The UV light passes through the planar Fresnel lens (9), the liquid - crystal screen (10), and the light - transmissive release film (11) in sequence and irradiates on the UV adhesive, so that the UV adhesive cures on the cold stamping film (3) to form an adhesive area consistent with the stamping pattern. (5) Start the winding and unwinding unit to convey the cold stamping film (3) forward, that is, move the cold stamping film (3) with the adhesive area out of the printing dish (12), then remove the uncured UV adhesive on the cold stamping film (3) through a rinsing device, and then remove the moisture in the adhesive area through a drying device. (6) The cold stamping film (3) with the adhesive area after drying passes between the printing material (6) and the laminating roller (7), and the adhesive area on the cold stamping film (3) contacts the surface of the printing material (6); the laminating roller (7) is controlled to be laminated with the printing material (6), and the adhesive area of ​​the cold stamping film (3) is firmly bonded to the surface of the printing material (6) by applying pressure. With the movement of the conveying unit and the winding of the cold stamping film (3), the excess cold stamping film (3) is peeled off from the printing material (6), and the hot stamping pattern is completely transferred to the surface of the printing material (6).

2. The plate-free three-dimensional cold stamping method according to claim 1, wherein In step (4), the contrast of the hot stamping pattern on the liquid crystal screen (10) is adjusted in real time, and the hot stamping patterns with different light and dark distributions are displayed in time-sharing manner, which can change the light and dark degree and light and dark time of the local pixel area, thereby changing the UV light transmission rate and exposure time, and realizing the control of the curing speed and curing time of the adhesive areas at different positions on the cold stamping film (3), thereby realizing a three-dimensional adhesive curing three-dimensional pattern with non-uniform height on the cold stamping film (3), wherein the curing height is adjustable within the range of 0.05-1mm, and finally transferred to the surface of the printing material (6), realizing a real three-dimensional hot stamping effect.

3. The plate-free three-dimensional cold stamping method according to claim 1, wherein In step (1), an integral lifting mechanism is arranged on the workbench (13) for adjusting the height of the workbench (13), and further adjusting the interval between the cold stamping film (3) and the light-transmitting release film (11).

4. The plate-free three-dimensional cold stamping method according to claim 1, wherein, In step (1), the UV curing light source (8) is implemented using a planar array UV light source.

5. The plate-free three-dimensional cold stamping method according to claim 1, characterized in that In step (1), the inner wall surface of the cavity of the workbench (13) is provided with a reflective film.

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