How to improve the quality of printing plate

Shaiban is the process of transferring the original image and text to the PS plate. It connects the plate-making and printing bridges. The Environmental Festival is of paramount importance throughout print quality management. How to improve the quality of printing plates, reduce waste, and reduce costs, according to their own practice, from the following aspects to talk about experience.
First, we must have a high sense of responsibility and professionalism 1. Shaiban operators should be proficient in the performance of Shaiban, technical parameters, etc., to cherish the equipment, the need for regular maintenance of the equipment to ensure the normal operation of the Shaiban.
2. Keep the environment clean and keep the temperature and humidity in the room. Check the original carefully before printing. If you do not meet the printing requirements, analyze and deal with the specific situation to avoid unnecessary waste. The two sides of the plate of the printing machine Wipe.
3. Refer to the process sheet to check whether the original specifications and dimensions meet the job ticketing requirements; whether the mouthwash, belt mark, color mark, and station mark are complete.
Second, the quality of the original 1. First we must check the density of the original. The density of the original original site is about 3.0, and the density of dots, texts, and lines at this time meets the requirements of printing. Just perform normal exposure development. However, in actual production, it is often encountered that some of the originals have low or high density, so they must be dealt with according to different situations.
a. The lower density of the original text, in the exposure process, due to the low density, easy to make the light through the edge of the network, so that the photosensitive layer should not see the photo decomposition of the light decomposition occurs, the dot gray after development, Smaller, if it is text, the lines will become lighter. The ink is not saturated when it is on the machine, which reduces the printing resistance rate and does not achieve the desired effect. For this type of original to take less exposure, less development methods.
b. The high density graphics (blank part density is greater than 0.05), the original surface has a layer of fog, the corresponding network points, lines are not clean and there is a layer of fog, this layer of fog when the light passes Obstruction, so that the bottom of the fog edge of the network is not completely decomposed. After the development, the dots are enlarged, in particular, the enlargement rate of the dark tone portion of the image is increased, and the dark tone is graded and paste-printed during printing, which also fails to achieve the desired effect. For this original version, multiple exposures and multiple development methods are required.
2. Due to the revision of some graphics, the entire original “open skylight” part has become more difficult for the printing operation. The edge of the tape is too close to the image to make the image pad virtual, because the overlap of the film base will cause static electricity, the middle sandwich is easy to absorb some dust, and small sand particles will make the image pad virtual, and some original image parts will be folded out of the horseshoe nest and exposed. After this, the image also appears imaginary. For these phenomena, it is required that the printing operators find timely solutions.
3. Some books and texts...
Third, the print version of the control signal stripe print operator to work on exposure and development before each match test to determine the exposure time suitable for printing and proofing, development time, developer concentration. Method: First, ensure that the temperature of the developer and developer concentrate meet the development requirements. Then take a small PS plate and put the signal bar on it to expose the signal strip. Before the test, it is necessary to take into account the different service objects of the printing plate, and the exposure time test should also be adjusted to different degrees.
a. proofing version: the signal bar after exposure and development of the four grayscale requirements sunning half, 2 small spots drying up, 50 points to restore the basic accurate, 80 outlets can not reduce the children and the edges of the network is clear and tidy.
b. Printed version: After the signal bar has been exposed and developed, four levels of gray scales are required to be sunburned by one and a half grades, and two dot-nets are sunburned. The 50- and 80-degree gay and pungent points are restored to be basically accurate and the edges of the dots are also required to be clear and tidy. The main reason for the inconsistency between printing and proofing is to solve the problem of the mechanical performance of the proofer and the printing press, and to ensure that the printed matter and proofs are basically consistent in terms of tone, hue, or saturation. .
Fourth, understand the PS version of the performance indicators, the correct use of the PS version in the replacement of the new PS version or use the same manufacturer of the PS version and the batch number is different, because the photosensitive liquid ratio is not the same, the speed will be different, so exposure The time, the development time, and the developer concentration have to be changed accordingly. In the use of developer, in order to achieve the ideal development of the theater effect is best to use with the PS version of the matching developer, because the PS plate produced by different manufacturers have strong or weak anti-alkaline properties, if the alkaline weak PS plate with strong alkali The developer is developed, and no photosensitive layer of the photo-decomposed portion is severely affected, and the dots are smaller after the development and the image tone is lost.
When the concentration of the developer is too large, not only the photosensitive layer is corroded, but also the oxide film of the printing plate is destroyed, so that the oleophilic performance of the printing plate is affected, and the printing durability of the PS plate is reduced. If the strong alkali-resistance PS plate is developed with a weakly alkaline developing solution, the phenomenon of incomplete development will occur. When the printing plate is dirty, the aluminum plate base will be subject to certain corrosion due to too long development time, affecting the PS plate. The effect of use.
Fifth, in addition to dirty, eraser, dry after the development of the PS version to remove dirt. Before removing dirt, the PS plate must be dried first, because most of the dirty areas are close to the image or text, and when the revised paste comes in contact with the PS plate, it is miscible with the surface of the plate and spreads to the surrounding water, which easily erodes the image. Or text, making the edges of the image blank, text lines lighter, or broken. In addition to dirty, use a brush tip to wipe a small amount of patch paste. Dirty spots need to be wiped cleanly and thoroughly removed in the shortest time, and then immediately rinse with water, to avoid the repair paste drying on the surface of the PS plate due to the long revision time.
In addition, the revision time is too long to make the layout dirty. After repairing the dirt, it is necessary to timely wipe the protective layer on the PS plate. If the glue is not wiped off in time, the hydrophilic layer of the PS plate will be oxidized and the hydrophilicity will be reduced. When printing, the PS plate will be dirty. Correct squeegee method: Wipe the thin layer on the surface of the plate with a proper amount of the tarpaulin and apply evenly so that all hydrophilic layers are protected. After the squeegee is removed, the PS plate is dried and then protected.
Protection method: Every two PS plates are separated by a neutral moisture-proof paper, the storage temperature is about 25°C, and the relative humidity is about 60.
If the quality of the printing plate is in a stable state for a long period of time, the printing staff must have the spirit of love and respect for the job, continuously accumulate experience in the work, and find a set of scientific standardized data suitable for printing and proofing, so that they can be handy when working to adapt to the current situation. This high-volume printing plate needs drying, which not only improves work efficiency but also ensures product quality.