Talk about the Design Points of Paper Gravure Prepress

First, the gravure prepress design 1. Concept design A good designer designed packaging products to be beautiful and elegant, patterns should be able to play a good contrast to the role of goods, promotional, text is simple and clear, and ink must Coordination and coordination make people feel at first glance, and reading in detail is like being on the scene. Since the designed packaging product is ultimately to be copied by the printing machine, the designer should consider the printing method, printing sequence, and the precision of the equipment before designing. 2. Problems that must be understood at design time When designing a sheet gravure print product, it is necessary to understand the gravure printing machine performance, paper type, printability, overprinting accuracy, printing color sequence, and reproducibility of screen printing (gravure printing machine pair The reproducibility of the cable version is limited, especially the transitional points are easily lost in high-speed printing, and the stencil is more serious), as well as the characteristics of gravure printing. After being well-established, the designed product can be suitable for gravure printing to get a perfect reproduction.

Second, gravure prepress technology arrangements 1. Process reviewer For technologists, process review is extremely important. Regardless of newly-developed design products, or replica products, they should be carefully reviewed. Because it helps to open the way of thinking, preparing for the post-printing and guiding the production. The technologist must also understand the performance of the gravure printing equipment, master the urgency and urgency of the printing process, and even operate the technology, think of the customer's thoughts, hurry the customer's urgency, and orderly carry out gravure prepress technology arrangement. 2. The color sequence arrangement has a thick gravure ink layer. If the color sequence is not arranged properly, the printed ink will completely cover the previous printing ink. Therefore, in the gravure printing, the arrangement of the color sequence is particularly important. The arrangement of the color sequence should be based on the type of product, the printing effect to be obtained, the depth of the ink, the degree of hiding, and the type of ink used (pigment type, dye type, special ink). The principle of the determination of the first color: 1 If the substrate is aluminum foil and the customer has a high requirement for color saturation, white should be the first color at this time. 2 If the substrate is plain white cardboard, the background color should be the first color if there is no special requirement. 3 If the background color is dark ink and clear ink are overprinted, the dark ink should be in the first color (if the sheet is imitation metal paper). 4 If the text or pattern has a light color and trapping relationship with the background color, the light color should be used as the first color, and the dark background color should be printed later, and the text or pattern on the light-colored version should be larger than the required size 0.2. Mm, in the dark version, the words or patterns are hollowed out according to the required size to facilitate print registration. 3. Typesetting According to the equipment's printing format, printing plate base processing drawings, refer to the sample size for reasonable layout (imposition).

Generally take a tight fight, if deep processing bronzing, embossed lines, in the middle plus 5 ~ 6mm knife. Because of the long hot stamping or embossed lines, the quality of the long-line hot stamping, embossed and mat copper produced is not high. If the pressure of the stamping machine is uneven, the operator's pad (regulating pressure) is relatively time-consuming. It is longer. Example of typesetting: The product is a clamshell cigarette pack. BOBST-820 gravure printing machine is used for on-line printing of large sheets. The cigarette factory adopts FK type packaging machine. The size of the single printing plate is 249mm x 98mm, and the imposition diagram is shown in Figure 1. 4. Platemaking requirements According to the sample, layout, customer requirements, base processing drawings for plate making, production of gravure version of the specific process parameters required are as follows: (1) plate cylinder wall thickness of 12 ~ 15mm. (2) The thickness of the copper plating layer is 1.2 to 1.5 mm. (3) The hardness of the copper plating layer reaches HV190. (4) The chromium layer hardness reaches HV950. (5) The chromium layer surface finish reaches 8-10. (6) The balance of the plate's dynamic balance can't exceed 0.3mm. (7) The incremental diameter of the printing plate in the printing sequence is 0.02mm.

5. Ink formulation China's large-scale ink factory to a small ink company, the production of gravure printing inks have been able to basically meet the requirements of printability. However, for the printing companies, it is not enough to satisfy the printability requirements. It needs to undergo multiple tests to meet the actual requirements. First, the hue, saturation, printability, postpress processing, friction resistance, high temperature resistance, leveling, adhesion, and resistance to folding, light, water, and bronzing of the ink should be prior to production. And so on to focus on testing. Neglecting any point may bring difficulties to production, fail to achieve an ideal input-output ratio, and may also cause difficulties for follow-up packaging, causing packaging users to feel a sense of distrust toward printing companies and even lose the market.

6. Formulation of Gravure Printing Sheets Gravure Printing Sheets play a decisive role in guiding production. Every kind of process item must be listed carefully and clearly. Only in this way can the production workshop implement the planned production step by step according to the quality standards required by the product and put the quality into consideration. There are many studies in gravure prepress design and process arrangement that require serious study. There are many problems worth exploring. It needs to be flexibly changed according to different products and different requirements.