Plastic gravure platemaking is more cumbersome than paper gravure platemaking and has many influencing factors. Designers should have a certain color knowledge, understand the printing process, and grasp the characteristics of platemaking in order to design high-quality product packaging quickly and well. Different types of packaging plate making requirements Plastic packaging bags can be divided into four categories: three-side seal, mid-bottom seal, three-dimensional middle seal and sheet material according to the method of making bags. The three-side seal is sealed around the packaging bag. The front and back dimensions are the finished size. It has a certain sense of overallity. The design is not constrained, and the front and rear designs have a certain consistency. Because the front and back dimensions are the same, the front can be designed first so that the back and the front echo. When making a plate, the front and back should be arranged on the same set of plate rollers. The midsole seal is sealed on the back, the front size is the finished size, the back is divided into two equal parts, and the sum of its width is equal to the width of the front, usually when designing, the front and back are unfolded, integrated design, and left and right Add 25px edge banding, the front and back are also on the same set of rollers. The three-dimensional middle seal is based on the middle bottom seal, and three-dimensional edges are added on both sides, and the front and back sides are also on the same set of plate rollers. Due to the limitation of printing materials, the front and back sides of the sheet must be designed separately, and the plates should be made separately. They cannot appear on the same set of cylinders at the same time. Main points of color processing of line version and mesh version 1. Line version A considerable part of gravure printing is line printing. Line printing is composed of lines and solid color blocks. It wins by modeling, and creates visual impact with solid (special color) to highlight the advantages of line printing. According to the characteristics of the gravure printing machine, the printing plate generally does not exceed 6 colors, and the spot color should be used as much as possible, and the color mark should be matched to facilitate the color matching during printing. A set of line version can form a series of products with many different combinations. When designing, you can first design a color matching scheme for users to choose. Since the line version does not have a sense of layering, attention should be paid to the overlapping treatment between colors to meet the overprinting requirements caused by the expansion and contraction of the substrate. 2. Mesh version The mesh version has extremely rich layers and ever-changing colors, but no matter how complex the layers are, they are composed of cyan, magenta, yellow, and black (special colors need to be added with special colors). The tone levels of the image are divided into Highlight, dark tone, and middle tone. Therefore, we must first know the gray balance data of the four-color ink and the printability of each layer, grasp the rule of dot change, and summarize the image layer processing method to make the product achieve the best visual effect. â‘ Adjustment of gray balance â‘¡Setting the tone value of highlight and bright areas For the highlight part, one is to adjust the three primary colors of the extreme highlight to 0, as the brightest part of the image tone, and the range of the highlight part can be enlarged if necessary; the second is to adjust the highlight white area that needs gradation to the smallest printable tone The value is determined according to multiple test proofs, and the minimum dot value is C6%, M5%, and Y5%. â‘¢Middle tone level processing Midtones are the top priority of the entire image. The middle tone level should achieve the best visual brightness. To this end, it can deepen its overall saturation or reduce the saturation according to the situation, but try not to affect the gray balance of the image, and only make local adjustments to the image. For example, a plate of fruit with bright colors can grasp the main colors of different fruits when processing, appropriately reduce green leaves to red, appropriately add red to red fruits, and reduce blue and red to yellow fruits. However, after the local area is locked, the micro-adjustment of the layers and colors should be carried out to make the product color cleaner, brighter and more pleasing. â‘£ Dark tone level processing In general, gravure printing is very poor in the level of 80% of the Internet access area. In this way, the layers of the deepest part and the second deepest part of the dark tone need to be pulled apart, and the level of the second deepest part is reduced to about 60%. Overprint processing between color plates Since plastic film materials are more flexible than paper, overprinting between color plates is a link that must be considered in the production of gravure front ends. The standard of the overprint processing is as follows. 1. The text version is usually black, and hollowing is not allowed when overprinting. If the text version is other colors, such as magenta, you can consider whether to overprint with the background color according to the size of the word. When the word is less than 12 pounds, it must be overprinted with the background color, but it still needs to consider whether the color of the text after the color overlay is eye-catching. If it affects the recognition effect, consider changing colors. 2. When the light color and the dark color are connected, generally set the light expansion value to 1 ~ 2PIXS. For larger layouts, the value can be increased appropriately. 3. When the spot color version is connected to the picture, the edge of the spot color version can be expanded without affecting the edge pixels of the picture. The value of the edge expansion is usually 1 ~ 2PIXS. 4. If printing opaque ink, such as gold ink, the printing sequence of the ink should be considered first, otherwise the gold ink will cover the relevant colors. If you have to do overprinting, you should also consider the problem that gold ink and other color inks will become dark and not bright when overprinting. 5. Silver ink is also a special ink. Light silver has certain transparency. Therefore, when using silver ink, it is necessary to determine whether the background color or related color is overprinted or hollowed out through design according to customer requirements. Dining Table,Grey Dining Table Set,Rectangle Table,Long Dining Table shandong Changheng Wood Co.,Ltd , https://www.changhengwood.com