Laying a background flat screen in the print design has the function of foiling the screen theme and beautifying the layout. Offset flat screen nets are generally 90 lines/inch, 133 lines/inch, 150 lines/inch, and 175 lines/inch, which can basically meet various special requirements. Under normal circumstances, the background flat screen selects 10% to 60% of the outlets. The percentage of outlets exceeds 60%, and the color of printed flat screens is relatively dark, with relatively few applications. When laying out the undertone flat screen according to the printed manuscript and customer requirements, the following points should be noted.
1. The design department should prepare the color flat screen color design. Before making the plate design, we must first help the customer to determine the laying background color screen according to the printing manuscript. However, most of the printing customers do not know what effect the colored flat screens are spread out from 1 to 10 percent of the outlets. At this time, they need to use chromatograms and color patches to allow customers to intuitively select the number of flat screen flat screens. Therefore, prepare yellow, red, magenta, blue, purple, cyan, green, and black different colors, and the percentage of printing dots is 10% to 100%, for customers to choose their own flat color screen. The design and plate-making staff should record the customer's choices in detail in order to ensure that the printing effect is satisfactory to the customer.
2. The copying department should provide enough negative-tone flat-screen films to cover the 10% to 90% of different screen points of the commonly used screen lines in order to have ample room for selection. Most of the negative-tone flat-screen films we use are scanned by the electric extensions. The surfaces must be clean and tidy. There are no scratches on the surface of the film and no dirt or dust covers the transparent screens. When copying, do not bend the negative film on the flat screen. Do not fold it. Place it flat. The light in the darkroom was dark. Note that it is not possible to mix negative film flat film with other films so as to prevent young workers who have just entered the factory from mistakenly thinking that they have not used the film for cutting. It is required to use a paper box to store the negative-drawing flat-screen film exclusively, and make obvious markings to avoid errors.
3. Choosing the right plate-making process Whether it is full-lay laying or partial-laying of the ground-color flat screen, first copy the original large-scale ply net according to the designer's intention and the position of the black and white manuscript before copying. window. The knife used to cut the red film should be sharp, and the window should be smooth, clean, and free from burrs.
When copying the background color of the flat screen, the shaded film should be placed on the bottom with a red film. The negative film should be laid on the negative film (the film should face upward), and then the film should be faced to the bottom. Place the negative film on the negative film, vacuum, you can copy. The film's film is placed on the surface of the film, which can reduce the defects such as dot enlargement and misrepresentation.
Under normal circumstances, there will be text, lines, and patterns on the flat surface of the background. If the color of the background flat screen is in the same color as the text, line, and pattern, a double exposure copy is required to make the background flat screen flat. Copy text, lines, and patterns to a film. If the background flat screen and the text, lines, and patterns above it are not a color, then a spot color flat screen film should be specifically copied.
4. When the secondary copy is processed for the second exposure copy, firstly use the negative plan flat screen film to copy out the positive background flat screen film according to the design requirements; then the negatives of the characters, lines, and patterns are just like the film on the film. Drill holes in the puncher to determine the position for secondary copies.
When copying, it is important to note that the relative position of the flat net and the top of the text, lines, and patterns can only be correct by the fixing action of the punching and hanging nails. When the requirement is not high, it can also be affixed firmly with transparent tape to avoid skewing.
5. Control the copying conditions The copying machine is kept clean, free of dust and dirt and is a prerequisite for laying down flat screens. The work habit of cultivating civilized production, cleanliness and hygiene is a basic management work for the plate-making work. The temperature and humidity of the darkroom are also critical. If the humidity is high, there will be irregular markings and spots on the original flat-screen film. Therefore, it is required to have a copy of the air-conditioning equipment in the darkroom and be capable of constant temperature and humidity control.
Copy the original color flat screen to master the correct exposure time, development time, control the temperature of the developer and the formula ratio of the developer solution. The background color of the original flat screen net copy required to be copied is strong, smooth, and round. The dot density is 2.30 or above, and the outlets do not expand and contract, and are not merging, fogging, or yellowing, and the layout of the outlets is uniform.
6. Make sure that the copy machine has good performance. When copying, it can only be sucked. When the film is in close contact with the film surface of the photographic film, it can copy the flat-screen film with stable quality. Therefore, it must be ensured that the vacuum pumping system of the duplicator is in good condition and the operation is in good condition.
If the copying machine is a model of a rolling blanket that is recovered by a miniature motor, in order to achieve stable vacuum suction and film stickiness, generally, one side of the blanket adjacent to the glass platen is covered with raised small dots. The role is to facilitate vacuum suction, because the depression between the small dot and the dot can form a gas extraction path, is conducive to suction suction. Another function of these small dots is to prevent the copy roller shutter from causing the film position to move. However, if the dots are stuck with dust, or the blanket is aged and desulfurized, the film will become dirty on copying, resulting in dirty dots and latent images on the copied dots, and eventually affecting the quality of the background flat screen. Therefore, when copying, a piece of cloth with a half size between the roller shutter and the photographic film should be placed so that the photographic film does not directly contact the roller blind.
Source: Printing Technology
1. The design department should prepare the color flat screen color design. Before making the plate design, we must first help the customer to determine the laying background color screen according to the printing manuscript. However, most of the printing customers do not know what effect the colored flat screens are spread out from 1 to 10 percent of the outlets. At this time, they need to use chromatograms and color patches to allow customers to intuitively select the number of flat screen flat screens. Therefore, prepare yellow, red, magenta, blue, purple, cyan, green, and black different colors, and the percentage of printing dots is 10% to 100%, for customers to choose their own flat color screen. The design and plate-making staff should record the customer's choices in detail in order to ensure that the printing effect is satisfactory to the customer.
2. The copying department should provide enough negative-tone flat-screen films to cover the 10% to 90% of different screen points of the commonly used screen lines in order to have ample room for selection. Most of the negative-tone flat-screen films we use are scanned by the electric extensions. The surfaces must be clean and tidy. There are no scratches on the surface of the film and no dirt or dust covers the transparent screens. When copying, do not bend the negative film on the flat screen. Do not fold it. Place it flat. The light in the darkroom was dark. Note that it is not possible to mix negative film flat film with other films so as to prevent young workers who have just entered the factory from mistakenly thinking that they have not used the film for cutting. It is required to use a paper box to store the negative-drawing flat-screen film exclusively, and make obvious markings to avoid errors.
3. Choosing the right plate-making process Whether it is full-lay laying or partial-laying of the ground-color flat screen, first copy the original large-scale ply net according to the designer's intention and the position of the black and white manuscript before copying. window. The knife used to cut the red film should be sharp, and the window should be smooth, clean, and free from burrs.
When copying the background color of the flat screen, the shaded film should be placed on the bottom with a red film. The negative film should be laid on the negative film (the film should face upward), and then the film should be faced to the bottom. Place the negative film on the negative film, vacuum, you can copy. The film's film is placed on the surface of the film, which can reduce the defects such as dot enlargement and misrepresentation.
Under normal circumstances, there will be text, lines, and patterns on the flat surface of the background. If the color of the background flat screen is in the same color as the text, line, and pattern, a double exposure copy is required to make the background flat screen flat. Copy text, lines, and patterns to a film. If the background flat screen and the text, lines, and patterns above it are not a color, then a spot color flat screen film should be specifically copied.
4. When the secondary copy is processed for the second exposure copy, firstly use the negative plan flat screen film to copy out the positive background flat screen film according to the design requirements; then the negatives of the characters, lines, and patterns are just like the film on the film. Drill holes in the puncher to determine the position for secondary copies.
When copying, it is important to note that the relative position of the flat net and the top of the text, lines, and patterns can only be correct by the fixing action of the punching and hanging nails. When the requirement is not high, it can also be affixed firmly with transparent tape to avoid skewing.
5. Control the copying conditions The copying machine is kept clean, free of dust and dirt and is a prerequisite for laying down flat screens. The work habit of cultivating civilized production, cleanliness and hygiene is a basic management work for the plate-making work. The temperature and humidity of the darkroom are also critical. If the humidity is high, there will be irregular markings and spots on the original flat-screen film. Therefore, it is required to have a copy of the air-conditioning equipment in the darkroom and be capable of constant temperature and humidity control.
Copy the original color flat screen to master the correct exposure time, development time, control the temperature of the developer and the formula ratio of the developer solution. The background color of the original flat screen net copy required to be copied is strong, smooth, and round. The dot density is 2.30 or above, and the outlets do not expand and contract, and are not merging, fogging, or yellowing, and the layout of the outlets is uniform.
6. Make sure that the copy machine has good performance. When copying, it can only be sucked. When the film is in close contact with the film surface of the photographic film, it can copy the flat-screen film with stable quality. Therefore, it must be ensured that the vacuum pumping system of the duplicator is in good condition and the operation is in good condition.
If the copying machine is a model of a rolling blanket that is recovered by a miniature motor, in order to achieve stable vacuum suction and film stickiness, generally, one side of the blanket adjacent to the glass platen is covered with raised small dots. The role is to facilitate vacuum suction, because the depression between the small dot and the dot can form a gas extraction path, is conducive to suction suction. Another function of these small dots is to prevent the copy roller shutter from causing the film position to move. However, if the dots are stuck with dust, or the blanket is aged and desulfurized, the film will become dirty on copying, resulting in dirty dots and latent images on the copied dots, and eventually affecting the quality of the background flat screen. Therefore, when copying, a piece of cloth with a half size between the roller shutter and the photographic film should be placed so that the photographic film does not directly contact the roller blind.
Source: Printing Technology