A Wide Color Gamut Color Management Method Applied to Gravure Printing

Abstract

The present application relates to a wide-color gamut color management method applied to gravure printing, including: S1, producing a standard test proof; S2, establishing a standard ICC file; S3, configuring the color manuscript of the product to be printed; S4, performing color matching between the ICC file of the color manuscript to be printed and the standard ICC file by means of channel separation, and completing color matching after determining that the matching effect is appropriate. The color data after completion of matching is used to generate a matching color file for digital proofing and simulated printing; S5, performing digital proofing and simulated printing through the matching color file to obtain a digital proof, comparing the digital proof with the color manuscript of the product to be printed, and determining the color reproducibility; S6, determining the printing plate cylinder preparation process of the product to be printed according to the data of the matching color file, so as to produce the printing plate cylinder and perform printing. The present application has the effect of effectively realizing the color reproduction of the substrate film layer structure printing.

Description

Technical Field

[0001] This application relates to the technical field of tunnel construction, and particularly to a wide - gamut color management method applied to gravure printing. Background Art

[0002] Color printing is a method of reproducing images or texts in color (in contrast to black - and - white printing, or monochromatic printing). It involves many steps, or conversion processes, to produce high - quality color reproductions.

[0003] In the traditional color market, color printing technologies are mainly divided into three categories, namely: production color, image color, and commercial color. This classification is mainly determined by the output requirements of customers. Production color is suitable for large - volume production, where high production speed and low unit printing cost are very important. Image color jobs must achieve a high quality level (usually requiring accurate color matching), but the printing volume of such jobs is generally not large. Commercial color is a rapidly developing field because color documents are becoming increasingly common in the office environment.

[0004] Regarding the above - mentioned related technologies, the inventor believes that there are the following defects: In image color printing, color pattern printing is performed on a base layer with a white background for scanning to obtain color parameter data, and pattern printing is carried out according to the obtained color parameter data. However, color patterns sometimes need to be printed on substrate layers such as aluminized films or matte films. There are differences between the substrate layer and the base layer with a white background, which will cause color differences in the final printed product and cannot effectively achieve the color reproducibility of the product pattern. Moreover, substrate film layer structures such as aluminized films or matte films cannot be directly used for digital printing applications, and digital proofing for simulation printing cannot be achieved. How to effectively achieve color reproduction in the printing of substrate film layer structures such as aluminized films is the main technical problem to be solved currently. Summary of the Invention

[0005] In order to effectively achieve color reproduction in the printing of substrate film layer structures, this application provides a wide - gamut color management method applied to gravure printing.

[0006] A wide - gamut color management method applied to gravure printing provided by this application adopts the following technical solutions:

[0007] A wide - gamut color management method applied to gravure printing includes the following steps:

[0008] Step S1, making a standard test sample, engraving a plurality of color block gravure rollers, the color block gravure rollers having a cell structure, the plurality of color block gravure rollers being respectively used for printing cyan, magenta, yellow, black, orange, green and violet, and obtaining a standard test sample having an IT8 color block layer by overprinting the plurality of color block gravure rollers;

[0009] Step S2, establishing a standard ICC file, scanning a standard test sample with a color measuring device to obtain color information of the IT8 color block printed on the standard test sample, and importing the color information into a color management software, and establishing a standard ICC file with the color management software;

[0010] Step S3, configuring the color draft of the product to be printed, scanning the color draft of the product to be printed by a color measuring device to obtain an ICC file of the color draft to be printed;

[0011] Step S4, color matching is performed between the ICC file of the color draft to be printed and the standard ICC file by using a channel color separation method, and color matching is completed after determining that the matching effect is appropriate, and the matched color data is completed to generate a matching color file for digital proofing simulation printing;

[0012] Step S5, performing digital proofing simulation printing by matching the color file to obtain a digital proof, comparing the digital proof with the color draft of the product to be printed to determine the color reproducibility;

[0013] Step S6: Determine the printing plate roller preparation process of the product to be printed according to the matching color file data, so as to manufacture the printing plate roller and perform printing.

[0014] By adopting the above technical scheme, a standard test sample printed with an IT8 color block layer is obtained by overprinting multiple color block gravure rollers, which is used as a scanning manuscript for generating a standard color file. The printed standard test sample with the IT8 color block is scanned by a color measuring device to obtain color standard data and standard parameters for making a color block gravure roller, and a standard ICC file is established by color management software. Then, the color draft of the product to be printed provided by the customer is scanned by the color measuring device to obtain the ICC file of the color draft to be printed. The ICC file of the color draft to be printed and the standard ICC file are color matched by a channel color separation method. After determining that the matching effect is appropriate, the color matching is completed. After the matched color data is completed, a matching color file for digital proofing simulation printing is generated. Finally, a corresponding printing plate roller is produced according to the color data in the matching color file. Printing is performed by the printing plate roller, thereby effectively realizing the color reproduction of the substrate film layer structure printing, reducing the color difference of the gravure printing products, and improving the color vividness of the gravure printing products by the wide color gamut color management method applied to gravure printing.

[0015] Preferably, in the step S1, the difference in the screen angles of the cell structures between adjacent color block gravure cylinders is more than 15°.

[0016] By adopting the above technical solution, the difference in the screen angles of the cell structures between two adjacent color block gravure cylinders is more than 15°, effectively reducing the possibility of moiré patterns in the color blocks after overprinting, improving the printing quality of IT8 color blocks, and enhancing the accuracy of color contrast.

[0017] Preferably, in the step S1, the difference in the engraving needle angles of the color block gravure cylinders is within ±0.3°.

[0018] By adopting the above technical solution, the accuracy of engraving the cells of the color block gravure cylinders is improved, thereby enhancing the printing quality of IT8 color blocks.

[0019] Preferably, in the step S2, the color measuring device includes a scanning table for placing the color proof of the standard test sample / print product to be printed and a spectrophotometer body disposed on the scanning table to scan the color proof of the standard test sample / print product to obtain color information. The scanning table is provided with a fixing mechanism for fixing the color proof of the standard test sample / print product to be printed.

[0020] By adopting the above technical solution, a fixing mechanism is provided to fix the color proof of the standard test sample / print product to be printed, reducing the possibility of the product to be scanned moving on the scanning table during the scanning process by the spectrophotometer body, and improving the accuracy of the scanning result.

[0021] Preferably, the scanning table has an adsorption chamber, and a plurality of adsorption ports communicating with the adsorption chamber are opened on the upper end surface of the scanning table. The fixing mechanism includes an air extraction pipe with one end communicating with the adsorption chamber and a micro vacuum pump connected to the other end of the air extraction pipe.

[0022] By adopting the above technical solution, the micro vacuum pump sucks air from the adsorption chamber of the scanning table through the air extraction pipe, so that the air above the scanning table continuously enters the adsorption chamber through the adsorption ports; at this time, a negative pressure space is formed above the scanning table, and the color proof of the standard test sample / print product to be printed placed on the scanning table is adsorbed and fixed on the upper end surface of the scanning table, reducing the possibility of the product to be scanned moving on the scanning table during the scanning process by the spectrophotometer body, and improving the accuracy of the scanning result.

[0023] Preferably, a sliding groove is horizontally formed in the lower part of the inner side wall of the suction port. The scanning table is provided with a cross plate slidably connected to the sliding groove. The cross plate is fixedly connected with a vertical plate disposed inside the suction port. The upper end surface of the vertical plate is flush with the upper end surface of the scanning table. The outer side walls of the vertical plate on both sides in the length direction are respectively abutted against the inner side wall of the suction port. The scanning table is provided with an adjusting assembly for adjusting the sliding position of the cross plate so as to adjust the size of the suction port.

[0024] By adopting the above technical solution, the sliding position of the cross plate is adjusted through the adjusting assembly, so as to adjust the sliding position of the vertical plate, and further facilitate the staff to adjust the size of the suction port according to substrates of different materials. When the product to be scanned is a flexible material (such as paper or film), the opening size of the suction port is adjusted to be reduced, so as to reduce the possibility of the product to be scanned being sunken, improve the flatness of the surface of the product to be scanned, and improve the scanning accuracy of the product. When the product to be scanned is a hard material (such as corrugated cardboard), the opening size of the suction port is adjusted to be increased, so as to increase the adsorption area of the product to be scanned, thereby improving the fixing strength of the product to be scanned and further reducing the possibility of the product to be scanned sliding. In addition, when the scanning table is in a non-working state, the sliding position of the vertical plate is adjusted through the adjusting assembly, so that the side surface of the vertical plate far from the cross plate abuts against the inner side wall of the suction port far from the sliding groove, realizing the closing of the suction port, effectively reducing the possibility of dust or impurities falling into the adsorption cavity through the suction port, thereby reducing the possibility of the suction pipe or the micro vacuum pump being blocked, and improving the service life of the suction pipe or the micro vacuum pump.

[0025] Preferably, a first installation groove is formed in the upper part of the inner side wall of the suction port. A first installation shaft is elastically rotatably connected in the first installation groove. The first installation shaft is fixedly wound with a first support rope. The other end of the first support rope is fixedly connected to the top of the side wall of the vertical plate.

[0026] By adopting the above technical solution, the first installation shaft is provided to provide an installation carrier for the first support rope, and the first support rope can be wound or unwound according to the change of the sliding position of the vertical plate, and the first support rope is kept in a straightened state. By arranging the first support rope, the suction port is further divided into several areas. When the product to be scanned made of flexible material is placed on the scanning table, the first support rope abuts against the lower end surface of the product to be scanned, thereby further reducing the possibility of the product to be scanned being sunken, improving the flatness of the surface of the product to be scanned, and improving the scanning accuracy of the product. When the side surface of the vertical plate far from the cross plate abuts against the inner side wall of the suction port far from the sliding groove, realizing the closing of the suction port, the first support rope will also be received in the first installation groove, thereby improving the sealing performance of the vertical plate to the suction port.

[0027] Preferably, a first torsion spring for forcing the first installation shaft to rotate to wind the first support rope is arranged in the first installation groove.

[0028] By adopting the above technical solution, the elastic rotation setting of the first mounting shaft is realized by using a coil spring. During the sliding process of the vertical plate towards the sliding groove, the first mounting shaft is driven to rotate by the first support rope, and the unwinding operation of the first support rope is realized. At this time, the coil spring converts the deformation into elastic potential energy, and when it has the condition for resetting, it can drive the winding shaft to rotate back. Based on this principle, after the first support rope on the first mounting shaft is pulled out, it has the ability to automatically wind back onto the first mounting shaft, so as to realize that the first support rope can extend or retract following the change of the sliding position of the vertical plate, and always keep the first support rope in a taut state.

[0029] Preferably, the adjusting assembly includes a sliding partition plate that is vertically slidably connected to the inner side wall of the adsorption cavity to divide the adsorption cavity into an upper chamber and a lower chamber, an adjusting hinge rod with one end hinged to the cross plate and the other end hinged to the sliding partition plate, and a telescopic driving member for driving the sliding partition plate to slide up and down. The sliding partition plate has an air extraction channel. The micro vacuum pump and the air extraction pipe are both disposed in the lower chamber. The air extraction pipe is a flexible pipe and is communicated with the air extraction channel of the sliding partition plate. The upper end surface of the sliding partition plate is provided with air extraction holes communicated with the air extraction channel.

[0030] By adopting the above technical solution, the telescopic driving member drives the sliding partition plate to slide up and down vertically, so as to drive the cross plate to slide horizontally through the adjusting hinge rod, and further adjust the sliding position of the vertical plate in the adsorption port, and then realize the adjustment of the size of the adsorption port. The micro vacuum pump and the air extraction pipe are both disposed in the lower chamber, improving the space utilization rate of the lower chamber and reducing the occupied volume of the scanning table. The micro vacuum pump sucks air into the upper chamber through the air extraction pipe, the sliding partition plate and the air extraction holes, so that the air above the scanning table continuously enters the air extraction channel through the adsorption port.

[0031] Preferably, the sliding partition plate is provided with an air extraction nozzle disposed in the upper chamber and communicated with the air extraction holes. The air extraction nozzle is a rubber pipe. There are two sliding grooves which are respectively disposed on the opposite inner side walls of the adsorption port. The vertical plates are correspondingly provided with two. The side surfaces of the two vertical plates close to each other are inclined so that the thickness dimension of the vertical plates gradually decreases from top to bottom, so that there is a space for the upper part of the air extraction nozzle to extend between the lower parts of the two vertical plates. Under normal conditions, the two vertical plates are in contact with each other so that the adsorption port is in a closed state. When the sliding partition plate rises, the two vertical plates slide away from each other so that the adsorption port is in a communicating state.

[0032] By adopting the above technical solution, the side surfaces of the two vertical plates close to each other are inclined, so that the thickness dimension of the vertical plates gradually decreases from top to bottom, and a space is formed between the lower parts of the two vertical plates for the upper part of the air extraction nozzle to extend into. As a result, the nozzle of the air extraction nozzle can be as close as possible to the product to be scanned. Moreover, when the sliding partition plate rises, the two vertical plates slide away from each other. The rising of the sliding partition plate reduces the volume of the upper chamber, thereby reducing the time for the micro air extraction pump to extract gas from the upper chamber, improving the air extraction efficiency, enabling the upper chamber to quickly reach the negative pressure requirement, and the air extraction nozzle also rises accordingly, and the air extraction port of the air extraction nozzle is closer to the product to be scanned, improving the adsorption and fixation effect on the product to be scanned.

[0033] In summary, the present application includes at least one of the following beneficial technical effects:

[0034] 1. A standard test sample with an IT8 color block layer printed thereon is obtained by overprinting multiple color block gravure printing cylinders and used as the scanning master for generating a standard color file. The standard test sample with IT8 color blocks obtained by printing is scanned by a color measurement device to obtain color standard data and standard parameters for making the color block gravure printing cylinders, and a standard ICC file is established through color management software. Then, the ICC file of the color proof to be printed provided by the customer is obtained by scanning the color proof of the product to be printed by the color measurement device. The ICC file of the color proof to be printed and the standard ICC file are color-matched by the channel separation method. After determining that the matching effect is appropriate, the color matching is completed. The color data after matching is used to generate a matching color file for digital proofing and simulating printing. Finally, a corresponding printing cylinder is made according to the color data in the matching color file, and printing is performed through the printing cylinder, effectively realizing the color reproduction of the substrate film layer structure, reducing the color difference of intaglio printing products, and being able to improve the color vividness of intaglio printing products by applying a wide-gamut color management method for intaglio printing;

[0035] 2. By setting the first support rope, the adsorption port is further divided into several regions. When the flexible product to be scanned is placed on the scanning table, the first support rope abuts against the lower end surface of the product to be scanned, thereby further reducing the possibility of the product to be scanned being sunken, improving the flatness of the surface of the product to be scanned, and improving the scanning accuracy of the product. When the side surface of the vertical plate away from the horizontal plate abuts against the inner wall of the adsorption port away from the sliding groove, the adsorption port is closed, and the first support rope will also be received in the first installation groove, thereby improving the sealing performance of the vertical plate to the adsorption port;

[0036] 3. When the sliding partition plate rises, the two vertical plates slide away from each other. The rising of the sliding partition plate reduces the volume of the upper chamber, thereby reducing the time for the micro air pump to extract gas from the upper chamber, improving the air extraction efficiency, enabling the upper chamber to quickly reach the negative pressure requirement, and the air extraction nozzle also rises accordingly. The air extraction port of the air extraction nozzle is closer to the product to be scanned, improving the adsorption and fixation effect on the product to be scanned. Description of the Drawings

[0037] Figure 1 is a schematic structural diagram of the standard test sample in Embodiment 1.

[0038] Figure 2 is a schematic overall structural diagram of the color measurement device in Embodiment 1.

[0039] Figure 3 is a schematic structural diagram of the standard test sample in Embodiment 2.

[0040] Figure 4 is a schematic structural diagram of the adsorption port on the scanning table in the open state in Embodiment 3.

[0041] Figure 5 is a schematic internal structural diagram of the scanning table in Embodiment 3.

[0042] Figure 6 is Figure 5 a partial enlarged schematic diagram at A.

[0043] Figure 7 is a schematic structural diagram of the adsorption port on the scanning table in the closed state in Embodiment 4.

[0044] Figure 8 is a schematic internal structural diagram of the scanning table in Embodiment 4.

[0045] Figure 9 is Figure 8 a partial enlarged schematic diagram at B.

[0046] Description of reference numerals: 1. Standard test sample; 11. Simulation base film layer; 12. IT8 color block layer; 13. Sample base layer; 2. Scanning table; 21. Adsorption chamber; 211. Upper chamber; 212. Lower chamber; 22. Adsorption port; 221. First installation groove; 222. First installation shaft; 223. First coil spring; 224. First support rope; 225. Second installation groove; 226. Second installation shaft; 227. Dust-proof cloth; 228. Second coil spring; 229. Second support rope; 220. Counterweight; 23. Sliding groove; 231. Through groove; 24. Horizontal plate; 241. Slide block; 25. Vertical plate; 3. Spectrophotometer body; 4. Robot arm; 41. Support base; 42. First connecting arm; 43. Second connecting arm; 5. Fixing mechanism; 51. Micro vacuum pump; 52. Suction pipe; 6. Adjusting assembly; 61. Sliding partition; 611. Air extraction channel; 612. Air extraction hole; 613. Air extraction nozzle; 62. Adjusting hinge rod; 63. Cylinder; Detailed implementation mode

[0047] The following will further elaborate on this application in conjunction with the attached Figures 1-9 drawings.

[0048] Embodiment 1:

[0049] The embodiment of this application discloses a wide color gamut color management method applied to intaglio printing, including the following steps:

[0050] Step S1, fabricate the standard test sample 1, and refer to Figure 1 , engrave several color block intaglio printing cylinders. In this embodiment, seven color block intaglio printing cylinders are provided, and the seven color block intaglio printing cylinders are respectively used for printing cyan, magenta, yellow, black, orange, green, and blue-violet. Each color block intaglio printing cylinder has a cell structure. The cell angles of the cell structures on adjacent color block intaglio printing cylinders differ by more than 15°. In order to improve the accuracy of engraving the cell structure, the engraving needle angles of the color block intaglio printing cylinders differ within ±0.3°. The standard test sample 1 includes a simulation base film layer 11. In this embodiment, the simulation base film layer 11 is an opaque film. Specifically, the simulation base film layer 11 is an aluminized film. Overprint printing is performed on the surface of the aluminized film through several color block intaglio printing cylinders to obtain an aluminized film with an IT8 color block layer 12. During the printing process, it is necessary to pay attention to keeping the printing surface of the aluminized film clean without dirt; the flatness of the aluminized film is good without wrinkles; the light screen transfer of the aluminized film is good, that is, there are no missing dots and no blank color blocks.

[0051] Step S2: Establish a standard ICC file. Scan the standard test sample 1 with a color measurement device to obtain the color information printed on the IT8 color patch layer 12 of the standard test sample 1, and import the color information into color management software. Specifically, the color management software can be Profilemake software, or it can also be Color tool, or a combined application of the two software. Establish a standard ICC file through the color management software. Among them, the ICC curve data requirement is ΔEab≤1.5. For unqualified data, reprint and scan. Multiple standard ICC files can be established, and the operator generates different standard ICC files according to different combination methods of seven colors.

[0052] Step S3: Configure the color manuscript of the product to be printed provided by the customer. Scan the color manuscript of the product to be printed provided by the customer with a color measurement device to obtain the ICC file of the color manuscript to be printed. Among them, the ICC curve data requirement is ΔEab≤1.5. For unqualified data, reprint and scan.

[0053] Step S4: Perform color matching on the ICC file of the color manuscript to be printed and the standard ICC file by the channel separation method. After determining that the matching effect is appropriate, complete the color matching. The matched color data generates a matching color file for digital proofing and simulating printing.

[0054] Step S5: Perform digital proofing and simulating printing through the matching color file to obtain a digital proof. Compare the digital proof with the color manuscript of the product to be printed to determine the color reproducibility.

[0055] Step S6: Determine the printing plate roller preparation process of the product to be printed according to the data of the matching color file, and then make the printing plate roller and perform printing.

[0056] In this embodiment, referring to Figure 1 、 Figure 2 , the color measurement device includes a scanning table 2 for placing the standard test sample 1 / color manuscript of the product to be printed and a spectrophotometer body 3 arranged on the scanning table 2 to scan the standard test sample 1 / color manuscript of the product to be printed to obtain color information. The scanning table 2 is provided with a robotic arm 4. The robotic arm 4 includes a support base 41 rotatably connected to the upper end surface of the scanning table 2, a first connecting arm 42 with one end rotatably connected to the support base 41, and a second connecting arm 43 rotatably connected to the other end of the first connecting arm 42. The spectrophotometer body 3 is installed at the free end of the second connecting arm 43. The support base 41 has a lifting function to adjust the height position of the spectrophotometer body 3, so as to facilitate the spectrophotometer body 3 to scan products to be scanned with different thickness dimensions. When it is necessary to scan the product to be scanned, the product to be scanned is fixedly connected to the scanning table 2 by pasting to achieve the fixation of the product to be scanned.

[0057] The implementation principle of Example 1 is as follows: a standard test sample 1 printed with an IT8 color block layer 12 is obtained by overprinting multiple color block gravure rollers, which is used as a scanned manuscript for generating a standard color file; the printed standard test sample 1 with an IT8 color block layer 12 is scanned by a color measuring device to obtain color standard data and standard parameters for making a color block gravure roller, and a standard ICC file is established by a color management software; then, a color draft of a product to be printed provided by a customer is scanned by a color measuring device to obtain an ICC file of the color draft to be printed; the ICC file of the color draft to be printed and the standard ICC file are color matched by a channel color separation method; after determining that the matching effect is appropriate, the color matching is completed; after the matched color data is completed, a matching color file for digital proofing simulation printing is generated; finally, a corresponding printing plate roller is manufactured according to the color data in the matching color file; printing is performed by the printing plate roller, thereby effectively realizing the color reproduction of the substrate film layer structure printing, reducing the color difference of the gravure printing products, and improving the color vividness of the gravure printing products by a wide color gamut color management method applied to gravure printing.

[0058] Embodiment 2: The difference from Embodiment 1 is that, referring to Figure 3 The simulation base film layer 11 is a transparent film or a matte film. In the present embodiment, the simulation base film layer 11 is a PET film, and a sample base layer 13 needs to be fixedly provided on the side of the simulation base film layer 11 away from the IT8 color block layer 12. The sample base layer 13 is a shading base layer. In the present embodiment, the shading base layer can be a shading paper or a shading plate. The side of the shading base layer close to the simulation base film layer 11 is set as a white background to highlight the color of the IT8 color block layer 12 and facilitate subsequent scanning.

[0059] Embodiment 3: The difference from Embodiment 1 is that, referring to Figure 4 , Figure 5 The scanning platform 2 has an adsorption chamber 21. The upper end surface of the scanning platform 2 is provided with a plurality of adsorption ports 22 connected to the adsorption chamber 21. The cross section of the adsorption ports 22 is square. The scanning platform 2 is provided with a fixing mechanism 5 for fixing the standard test sample 1 / the color draft of the product to be printed. The fixing mechanism 5 includes an exhaust pipe 52 having one end connected to the adsorption chamber 21 and a micro vacuum pump 51 connected to the other end of the exhaust pipe 52.

[0060] Reference Figure 5 , Figure 6, a sliding groove 23 is horizontally formed in the lower part of one inner side wall of the adsorption port 22 of the scanning table 2. The scanning table 2 is provided with a cross plate 24 slidably connected to the sliding groove 23. The end face of the cross plate 24 away from the sliding groove 23 is fixedly connected with a vertical plate 25 disposed inside the adsorption port 22. The cross plate 24 and the vertical plate 25 form an L shape. The upper end face of the vertical plate 25 is flush with the upper end face of the scanning table 2. The outer side walls of the vertical plate 25 on both sides in the length direction are respectively abutted against the inner side wall of the adsorption port 22. The scanning table 2 is provided with an adjusting assembly 6 for adjusting the sliding position of the cross plate 24 so as to adjust the size of the adsorption port 22.

[0061] The adjusting assembly 6 includes a sliding partition plate 61, an adjusting hinge rod 62 and a telescopic driving member. The sliding partition plate 61 is horizontally arranged and is vertically slidably connected to the inner side wall of the adsorption cavity 21 to divide the adsorption cavity 21 into an upper chamber 211 and a lower chamber 212. The sliding partition plate 61 has an air extraction channel 611. An air extraction hole 612 communicating with the air extraction channel 611 is formed in the upper end face of the sliding partition plate 61. The position of the air extraction hole 612 corresponds to that of the adsorption port 22. The micro vacuum pump 51 and the air extraction pipe 52 are both disposed inside the lower chamber 212. The air extraction pipe 52 is a flexible pipe and is communicated with the air extraction channel 611 of the sliding partition plate 61.

[0062] A through groove 231 communicating with the sliding groove 23 is horizontally formed in the inner wall of the top of the upper chamber 211. The cross plate 24 is fixedly connected with a slider 241 slidably connected to the through groove 231. One end of the adjusting hinge rod 62 is hinged to the slider 241 and the other end is hinged to the upper end face of the sliding partition plate 61. The telescopic driving member is disposed inside the lower chamber 212 for driving the sliding partition plate 61 to slide up and down. Specifically, the telescopic driving member is a cylinder 63. The cylinder body of the cylinder 63 is fixedly connected to the inner wall of the bottom of the lower chamber 212. The piston rod of the cylinder 63 is vertically arranged and is fixedly connected to the lower end face of the sliding partition plate 61. Under normal conditions, the outer side wall of the vertical plate 25 away from the sliding groove 23 abuts against the inner side wall of the adsorption port 22, so that the adsorption port 22 is in a closed state, effectively reducing the possibility of dust or impurities falling into the adsorption cavity 21 through the adsorption port 22, thereby reducing the possibility of blockage of the air extraction pipe 52 or the micro vacuum pump 51 and improving the service life of the air extraction pipe 52 or the micro vacuum pump 51. When the piston rod of the cylinder 63 extends to drive the sliding partition plate 61 to rise, the cross plate 24 is driven to slide towards the direction close to the sliding groove 23 through the adjusting hinge rod 62, so that the adsorption port 22 is in a communicating state.

[0063] An upper portion of an inner sidewall of the adsorption port 22 away from the sliding groove 23 is provided with a first mounting groove 221. A first mounting shaft 222 is elastically rotatably connected in the first mounting groove 221. The first mounting shaft 222 is fixedly wound with a first support rope 224. The other end of the first support rope 224 is fixedly connected to the top of the sidewall of the vertical plate 25. A plurality of first support ropes 224 are provided and are distributed along the axial direction of the first mounting shaft 222. A first torsion spring 223 is arranged in the first mounting groove 221 to force the first mounting shaft 222 to rotate so as to wind up the first support rope 224. By providing the first support rope 224, the adsorption port 22 is further divided into several regions. And when a flexible material to-be-scanned product is placed on the scanning table 2, the first support rope 224 abuts against the lower end surface of the to-be-scanned product to support the to-be-scanned product, thereby reducing the possibility of the to-be-scanned product being sunken, improving the flatness of the surface of the to-be-scanned product, and improving the scanning accuracy of the product.

[0064] The implementation principle of Embodiment 3 is as follows: By adjusting the sliding position of the horizontal plate 24 through the adjusting assembly 6, the sliding position of the vertical plate 25 is adjusted, and thus it is convenient for the staff to adjust the size of the adsorption port 22 according to different materials of the base material. When the to-be-scanned product is a flexible material (such as paper or film), the opening size of the adsorption port 22 is adjusted to be reduced, thereby reducing the possibility of the to-be-scanned product being sunken, improving the flatness of the surface of the to-be-scanned product, and improving the scanning accuracy of the product. When the to-be-scanned product is a hard material (such as corrugated cardboard), the opening size of the adsorption port 22 is adjusted to be increased, increasing the adsorption area for the to-be-scanned product, thereby increasing the fixing strength of the to-be-scanned product and further reducing the possibility of the to-be-scanned product slipping.

[0065] Embodiment 4: The difference from Embodiment 3 is that, referring to Figure 7 , Figure 8 , Figure 9 , two sliding grooves 23 are provided and are respectively arranged on two opposite inner sidewalls of the adsorption port 22, and two corresponding horizontal plates 24 and vertical plates 25 are provided. An upper portion of the inner sidewall of the adsorption hole is provided with a second mounting groove 225 above the sliding groove 23. A second mounting shaft 226 is elastically rotatably connected in the second mounting groove 225. The second mounting shaft 226 is fixedly wound with a dust-proof cloth 227. The other end of the dust-proof cloth 227 is fixedly connected to the top of the sidewall of the vertical plate 25. A second torsion spring 228 is arranged in the second mounting groove 225 to force the second mounting shaft 226 to rotate so as to wind up the dust-proof cloth 227.

[0066] A plurality of second support ropes 229 are provided at the tops of the opposite side walls of the two vertical plates 25. A rope-passing channel for the second support ropes 229 to pass through is formed in the top wall of the vertical plate 25. The opening of the rope-passing channel extends to the lower end face of the horizontal plate 24. Both ends of the second support rope 229 are respectively passed through the rope-passing channels of the two vertical plates 25. The end of the second support rope 229 extends into the upper chamber 211, and a counterweight 220 placed in the upper chamber 211 is fixedly connected to the end of the second support rope 229, so that the second support rope 229 is always in a taut state.

[0067] The sliding partition 61 is provided with an air extraction nozzle 613 placed in the upper chamber 211 and communicating with the air extraction hole 612. The air extraction nozzle 613 is a rubber tube. The cross-section of the air extraction nozzle 613 is in a waist shape. The length direction of the cross-section of the air extraction nozzle 613 is parallel to the length direction of the vertical plate 25. One side surface of the two vertical plates 25 close to each other is inclined so that the thickness dimension of the vertical plate 25 gradually decreases from top to bottom, so that there is a space for the upper part of the air extraction nozzle 613 to extend between the lower parts of the two vertical plates 25.

[0068] The implementation principle of Embodiment 4 is as follows: Under normal conditions, the upper parts of the two vertical plates 25 are in contact with each other so that the adsorption port 22 is in a closed state. When the piston rod of the cylinder 63 extends to drive the sliding partition 61 to rise, the two vertical plates 25 slide away from each other so that the adsorption port 22 is in a communicating state. The rising of the sliding partition 61 reduces the volume of the upper chamber 211, thereby reducing the time for the micro air pump to extract gas from the upper chamber 211, improving the air extraction efficiency, enabling the upper chamber 211 to quickly reach the negative pressure requirement, and the air extraction nozzle 613 also rises accordingly. The air extraction port of the air extraction nozzle 613 is closer to the product to be scanned, improving the adsorption and fixation effect on the product to be scanned.

[0069] The above are all the preferred embodiments of this application. The protection scope of this application is not limited accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of this application should be covered within the protection scope of this application.

Claims

1. A wide color gamut color management method applied to gravure printing, characterized in that: It includes the following steps: Step S1: Produce a standard test sample (1), engrave several color block gravure cylinders. The color block gravure cylinders have a cell structure. The several color block gravure cylinders are respectively applied to the printing of cyan, magenta, yellow, black, orange, green, and blue-violet. Through the overprint printing of the several color block gravure cylinders, a standard test sample (1) with an IT8 color block layer (12) is obtained; Step S2: Establish a standard ICC file. Scan the standard test sample (1) through a color measurement device to obtain the color information of the IT8 color block layer (12) printed on the standard test sample (1), and import the color information into color management software. Establish a standard ICC file through the color management software; Step S3: Configure the color manuscript of the product to be printed. Scan the color manuscript of the product to be printed through a color measurement device to obtain the ICC file of the color manuscript to be printed; Step S4: Perform color matching on the ICC file of the color manuscript to be printed and the standard ICC file by the method of channel separation. After determining that the matching effect is appropriate, complete the color matching. The color data after completion of the matching generates a matching color file for digital proofing and simulating printing; Step S5: Perform digital proofing and simulating printing through the matching color file to obtain a digital proof. Compare the digital proof with the color manuscript of the product to be printed to determine the color reproducibility; Step S6: Determine the printing cylinder preparation process of the product to be printed according to the data of the matching color file, so as to make the printing cylinder and perform printing; In the step S2, the color measurement device includes a scanning table (2) for placing a standard test sample (1) / a color proof of a product to be printed, and a spectrophotometer body (3) arranged on the scanning table (2) to scan the standard test sample (1) / the color proof of the product to be printed to obtain color information. The scanning table (2) is provided with a fixing mechanism (5) for fixing the standard test sample (1) / the color proof of the product to be printed. The scanning table (2) has an adsorption cavity (21), and a plurality of adsorption ports (22) communicating with the adsorption cavity (21) are formed on the upper end surface of the scanning table (2). The fixing mechanism (5) includes an air extraction pipe (52) with one end communicating with the adsorption cavity (21) and a micro vacuum pump (51) connected to the other end of the air extraction pipe (52). A sliding groove (23) is formed in the lower part of the inner side wall of the adsorption port (22) in the horizontal direction. The scanning table (2) is provided with a cross plate (24) slidably connected to the sliding groove (23). The cross plate (24) is fixedly connected with a vertical plate (25) placed in the adsorption port (22). The upper end surface of the vertical plate (25) is flush with the upper end surface of the scanning table (2). The outer walls on both sides of the vertical plate (25) in the length direction are respectively abutted against the inner side walls of the adsorption port (22). The scanning table (2) is provided with an adjusting component (6) for adjusting the sliding position of the cross plate (24) so as to adjust the size of the adsorption port (22). The adjusting component (6) includes a sliding partition plate (61) slidably connected to the inner side wall of the adsorption cavity (21) in the vertical direction to divide the adsorption cavity (21) into an upper chamber (211) and a lower chamber (212), an adjusting hinge rod (62) with one end hinged to the cross plate (24) and the other end hinged to the sliding partition plate (61), and a telescopic driving member for driving the sliding partition plate (61) to slide up and down. The sliding partition plate (61) has an air extraction channel (611). The micro vacuum pump (51) and the air extraction pipe (52) are both arranged in the lower chamber (212). The air extraction pipe (52) is a flexible pipe and communicates with the air extraction channel (611) of the sliding partition plate (61). An air extraction hole (612) communicating with the air extraction channel (611) is formed on the upper end surface of the sliding partition plate (61). The sliding partition plate (61) is provided with an air extraction nozzle (613) arranged in the upper chamber (211) and communicating with the air extraction hole (612). The air extraction nozzle (613) is a rubber pipe. There are two sliding grooves (23) which are respectively arranged on the opposite inner side walls of the adsorption port (22). Corresponding to this, there are two vertical plates (25). The side surfaces of the two vertical plates (25) close to each other are inclined so that the thickness dimension of the vertical plate (25) gradually decreases from top to bottom, so that there is a space for the upper part of the air extraction nozzle (613) to extend between the lower parts of the two vertical plates (25). Under normal conditions, the two vertical plates (25) are abutted against each other so that the adsorption port (22) is in a closed state. When the sliding partition plate (61) rises, the two vertical plates (25) slide away from each other so that the adsorption port (22) is in a communicating state.On the upper part of the inner side wall of the adsorption port (22), a second installation groove (225) located above the sliding groove (23) is provided. A second installation shaft (226) is elastically rotatably connected in the second installation groove (225). A dust-proof cloth (227) is fixedly wound around the second installation shaft (226). The other end of the dust-proof cloth (227) is fixedly connected to the top of the side wall of the vertical plate (25). A second torsion spring (228) is arranged in the second installation groove (225) to force the second installation shaft (226) to rotate to wind up the dust-proof cloth (227). A plurality of second support ropes (229) are arranged at the tops of the opposite side walls of the two vertical plates (25). A rope-passing channel for the second support rope (229) to pass through is provided at the top of the top wall of the vertical plate (25). The opening of the rope-passing channel extends to the lower end surface of the cross plate (24). The two ends of the second support rope (229) respectively pass through the rope-passing channels of the two vertical plates (25). The end of the second support rope (229) extends into the upper chamber (211). A counterweight block (220) placed in the upper chamber (211) is fixedly connected to the end of the second support rope (229), so that the second support rope (229) is always in a taut state.

2. The wide - gamut color management method applied to intaglio printing according to claim 1, wherein: In the said step S1, the screen angles of the cell structures between adjacent color block gravure cylinders differ by more than 15°; 3. The wide-gamut color management method for intaglio printing according to claim 1, characterized in that: In the said step S1, the engraving needle angles of the color block gravure cylinders differ within ±0.3°; 4. A wide - color - gamut color management method applied to intaglio printing according to claim 1, characterized in that: On the upper part of the inner side wall of the adsorption port (22), a first installation groove (221) is provided. An first installation shaft (222) is elastically rotatably connected in the first installation groove (221). The first installation shaft (222) is fixedly wound with a first support rope (224). The other end of the first support rope (224) is fixedly connected to the top of the side wall of the vertical plate (25); 5. A wide - color - gamut color management method for intaglio printing according to claim 4, characterized in that: A first coil spring (223) for forcing the first installation shaft (222) to rotate to wind up the first support rope (224) is arranged in the first installation groove (221).

Images