Q & A on the hottest screen printing process

Q & A on screen printing process

What are the advantages of UV cold light lamp

answer: in the light source used for silk printing and plate making, because the electronic rectifier is used for the ultraviolet cold light lamp, the light intensity emitted is not affected by the electric voltage, and it can be started with only 130v voltage. Its luminous range is exactly the range required by photosensitive materials. This kind of lamp can run continuously and start continuously, with low calorific value and less one-time investment. It is the most ideal light source for screen printing plate making

the service life of ultraviolet cold light tubes is generally 1000 hours, that is, three basic configurations of cumulative work Intelligence: host, microcomputer, and printer. If the time is more than or close to 1000 hours, the tubes should be replaced. Usually, the tubes can be replaced after the cumulative working time is about 750 hours, so as to ensure the printing quality

how to dissolve the film removal powder

answer: because the dissolution rate of the film removal powder in water is very slow, it cannot be dissolved at one time. Therefore, the correct way to dissolve the film removal powder is to dissolve it several times, that is, dissolve a part first and pour it out, then add fresh water to stir and dissolve it, and then pour it out. In this way, it can be dissolved completely in four to five times. In addition, when dissolving the film removal powder, a small amount of acid can be added, and 1~2ml per kilogram of water can effectively speed up the dissolution rate

what should we pay attention to when coating photosensitive adhesive

answer: first of all, pay attention to the coating speed when coating photosensitive adhesive, because the coating speed is too fast, which is easy to produce pinholes; Too slow, the glue is easy to leak into the ink surface, and it is easy to cause uneven gluing. Therefore, the photosensitive adhesive should be coated at a medium uniform speed. In addition, the brush can not be used to brush the photosensitive adhesive, because the brushing is uneven, and the surface of the brushed adhesive layer is uneven. It can only be hard, preferably coated with stainless steel glue applicator

how to apply photosensitive adhesive to coarse mesh silk

answer: pinholes often appear when coating photosensitive glue on coarse mesh silk (such as 30 mesh and 50 mesh silk). In order to avoid these failures, the photosensitive adhesive should be thicker. When coating for the first time, the printing surface should be scraped back and forth several times to fully wet the wire, and then scrape the remaining adhesive on the ink surface. After drying, on the printing surface, scrape it for 2 ~ 3 times continuously, and the speed should be slightly faster

how to determine the number of wires and wire mesh

answer: for the addition in silk printing, it can generally reach 80 lines/inch, and the maximum can reach 100 lines/inch. From the perspective of printing clarity, 80 lines/inch and 65 lines/inch have better visual effects. The number of lines is too high, and the dots are easy to paste. After the number of wires is set, the corresponding number of wire mesh can be determined. Generally speaking, the number of wire mesh is 3.5~6 times of the number of wires. For example, the number of wires is 80 Wires/inch, the minimum mesh number is 8, and the service life is 0.3.5=280 mesh

how to eliminate the faults in silk plate development

answer: when developing the silk plate, sometimes there will be some faults due to factors such as technology, materials and equipment. For these faults, we should analyze them in detail. If they cannot be eliminated correctly, it will affect the follow-up work

1. The silk ink surface is sticky and has paste like substances. Through observation, it can be seen that the sticky material is an uncrosslinked adhesive film, which dissolves in water and becomes sticky. Therefore, the ink surface adhesive layer should not be coated too thick, and the printing time should be appropriately extended

2. The adhesive layer on the printing surface falls off. For film paper, if it develops and falls off on polyester yarn, it often falls off due to poor grinding, that is, the yarn coarsening treatment is not good enough, and the adhesion fastness is poor. Another possibility is that the printing time is too short, and the film dissolves and falls off after swelling

elimination methods: first, increase grinding time; Second, increase the printing time. When developing, rubbing the glue surface with your finger several times on the glue film machine will hair and produce pinholes. This is caused by insufficient printing time, so you can increase the printing time under other conditions unchanged. When developing, the central image of the plate is very good, and the adhesive film is firm, while the local adhesive film on the edge of the image is easy to fall off. This phenomenon shows that the printing time is appropriate. As for the edge of local film removal, there are three possibilities: first, the edge light is weak, and the printing is insufficient; Second, the edge of the local glue is too thick; Third, some parts were not dried. Therefore, it is necessary to find out the reasons for the above three possibilities and correct them

why is it difficult to ensure the safety of this utilization field because of the strict regulatory requirements for the edge of image lines to be stripped

answer: if the adhesive layer around the image is too thin and the printing plate is too much, it will make it difficult to remove the film. The edge of the line is often in contact with the ink. After each printing, the edge ink cannot be cleaned. Some components in the ink will cause the adhesive film to harden slowly. The longer the time is, the harder it is to remove the film. Therefore, the ink must be thoroughly cleaned with a hole opening agent (ink cleaning agent) every time it is completed

how to clear the turtle shadow on the version

answer: Turtle shadow is mainly formed by dyeing the colorant in the adhesive layer and the color in the ink on the silk. Turtle shadow will bring some difficulties to the positioning of the printing plate during the secondary plate making, making the line of sight blurred. To remove turtle shadow, soak it in turtle shadow detergent for about 10 minutes, and then wash it with tap water

is it possible to apply photosensitive adhesive and film paper on the silk plate that has not been dried

answer: the wet silk plate cannot be coated with photosensitive glue immediately, nor can it be coated immediately. Because there is water on the wet silk surface, when coating photosensitive adhesive, the emulsion and surface floating water cannot be evenly dissolved, resulting in serious uneven coating, or even no glue; When the sensitization film is applied, the surface floating water will reduce the sensitization effect. Therefore, it must be coated or coated after drying

how to mix and use photosensitive powder correctly

answer: when preparing glue, it is best to use a small amount of distilled water (about 50ml). First dissolve the photosensitive powder into a solution, and then start the experimental machine again to measure the accurate value into the lotion. In this way, it is easy to mix evenly, and the photosensitive powder will not solidify into particles due to uneven mixing. After the photosensitive powder is poured into the latex, it should be stirred evenly immediately, otherwise the photosensitive powder accumulated on the latex surface will absorb moisture, solidify and agglomerate, so it cannot be stirred evenly. However, the newly prepared photosensitive adhesive cannot be coated immediately, because bubbles will be generated during the mixing of the adhesive, and it will take about 2 hours to be coated