Quality Control Methods of Different Paper Types of Jewelry Boxes

Quality Control Methods of Different Paper Types of Jewelry Boxes

In the packaging and printing process, different materials are often used to print the same or similar layout, such as the inner and outer packaging of the product, trademarks, manuals and other series of Jewelry Boxes. Generally, the color design of the graphic or logo on the printing layout is basically the same, but due to Due to the differences in the characteristics of the substrates, the printing equipment, ink properties and process forms used by some products are not necessarily the same, and customers often require that the printing color requirements of the series of products are basically the same, and there should be no obvious color difference. The actual production process shows that it is difficult to control the ink color quality of a series of Jewelry Boxes of different materials. It requires careful design in the process technology and careful control of the operation technology in order to obtain better printing quality results and meet the quality requirements of customers.

1. Characteristic analysis and process determination method of a series of printed matter

The so-called series of printed matter means that the specifications of the inner and outer packaging of the same product are different or the printing materials used in the complete set of products are different, but the layout structure or color of the pictures and texts are the same or similar. Due to differences in material properties or printing layout specifications, the adaptability of the printing process is also very different. For example, the surface printing materials of corrugated boxes and color boxes in the outer packaging include white board paper, kraft card or boxboard paper, etc., and the carton packaging materials include white board paper, kraft card, white card, glass card, copper plate card, PE coated paper, etc. etc., flexible packaging plastic film, cellophane, tissue paper, glossy paper, copy paper, offset paper, vacuum aluminized paper, laser paper, etc. Corrugated cardboard has large thickness, surface flatness characteristics, and the printing process of PE coated paper, plastic film, cellophane, tissue paper, and vacuum aluminized paper. Considering the characteristics of materials and the safety and hygiene quality of product packaging, it is suitable for flexographic printing. Printing with water-based ink can better ensure the quality of the product. For pre-printed color box surface paper, color box printed whiteboard paper, kraft card; vacuum aluminized paper, laser paper and other materials, gravure or flexo process can be used for large quantities, so that both printing quality and production cost can be obtained. better balance. For whiteboard paper, kraft card, white card, glass card, copperplate card products with a quantity of about 100,000 prints, as well as glossy paper, copy paper, offset paper, vacuum aluminized paper, and laser paper, the offset printing process is more appropriate. Among them, glossy paper and copy paper have low quantitative basis and are not suitable for high-speed automatic paper feeding. Low-speed 01 offset presses can be used for printing, so as to better ensure the overprint quality of products.

2. Pay attention to the process technology control of prepress layout design

Nowadays, many printed materials are electronic manuscripts designed and produced by customers or advertising companies. Due to their incomplete understanding of the printing process, the manuscripts produced often cannot meet the requirements of the printing process. Taking a series of prints with the same textured layout as an example, due to the different printing materials used, there will be large differences in the printing colors. It is the paper plate (whiteboard paper material) and paper cup (single-sided PE-coated paper) that are also printed by offset printing process. Due to the good surface smoothness of the whiteboard paper material, the amount of ink absorption is small, while the single-sided PE coating The surface of the paper is relatively rough, and the amount of ink absorption is larger. Using these two materials to print a layout with the same texture structure, the color will be quite different. Generally, the printing color of single-sided PE coated paper is obviously lighter than that of whiteboard paper. The adjustment of ink volume and pressure often cannot well overcome the problem of color difference caused by the difference in printing performance of materials. Generally, the dot area of the main color of the printed single-sided PE coated paper should be appropriately adjusted to a larger size through the plate-making design, so that the printing color can be approximated. Therefore, when receiving a series of prints with the same texture layout and different printing materials, it is necessary to carefully analyze the layout structure of the manuscript and the characteristics of the material to be printed, and then determine a reasonable plate-making design plan, that is, according to Material gloss, printing ink absorption performance, and reasonably adjust the dot area of a certain product layout to ensure that the colors printed on different materials are similar.

3. Pay attention to the technological control of the imposition direction

For a printed product with a multi-imposition structure, several different types of layouts are usually spelled on one sheet. If the differences in printing colors of different varieties are not considered, and different varieties with large color differences are spelled in the same longitudinal direction, then once the longitudinal layout is in which If the printing color of a certain layout is light or dark, it is difficult to adjust the ink output through the ink fountain to realize the ink color control of a certain type of layout corresponding to the vertical layout. Take into account the printing color of the overall vertical layout. Therefore, for multi-imposed paper plates, paper cups, trademarks and other products, it is best to spell the same variety or varieties with similar colors in each longitudinal position, so as to facilitate the effective adjustment of the ink coating amount. Do not combine several products with large color contrast in the same vertical orientation, because this is the most likely to cause color difference in imposition printing. Even if the printing color can be controlled by adjusting the ink coating amount, it is easy to produce chain printing quality problems, such as Bad situations such as drawing paper wool, pasted version, dirty version, etc.

Fourth, adjust and control the size of the dot through the printing process

The main feature of the series of prints is that the graphics and text are basically the same, but the size is different, while the characteristics of the substrate materials are completely different. If the reticulated structure of the film that has been produced is the same, it can be considered that in the printing process technology, according to the gloss and ink absorption of the substrate, the exposure time of a certain product's main color printing plate can be properly controlled. Realize the adjustment of dot size. Taking the substrates of the series of products as an example, there are glass cards and offset paper. The offset paper has a relatively rough layout and a large amount of ink absorption. The exposure time of the main color version can be appropriately shortened to achieve the purpose of increasing the dot area. The ink color of the printed offset paper printed matter can be close to the ink color of the printed matter of the glass card, and it is not easy to suffer from the problem of pasting. However, it must be pointed out that there is a limit to the adjustment of the dot size by the printing process, and it can only be adjusted in a small amount. If the exposure time is too short, the dark and white points of the layout are prone to smearing, and the layering of the layout is poor. Therefore, the exposure time should be adjusted to an appropriate degree. For example, the original normal exposure should be 140S, and the shortened exposure time should be controlled between 110-120S.

Five, by adjusting the printing pressure to control the printing color

Printing pressure is the medium of imprint transfer. The size of printing pressure directly reflects the depth of printing ink, especially in letterpress printing process. The size of pressure has a great influence on the depth of printing ink. When the printing pressure increases, the printing color will appear. The deepening phenomenon, on the contrary, reduce the printing pressure, and the printing color will appear lighter. For a series of prints of different substrates, when the surface of the printed material is rough, the printing pressure can be appropriately increased to deepen the printing color, so that the color of the printed matter of different materials can be approximated. However, the printing pressure adjustment should also be controlled to an appropriate degree. Excessive pressure adjustment will easily accelerate the wear of the printing plate, and it is easy to cause chain quality problems such as smearing and large deformation of the printing layout. This is a problem that should be paid attention to when operating the printing process. . Generally, the adjustment of letterpress printing pressure increase should not exceed 30 filaments, otherwise, the large printing deformation will directly affect the overprint quality of the product.

6. Control printing color through ink hue adjustment

Four-color prints are printed with standard four-color inks according to the conventional process. However, when there is a significant difference in the color of a certain color, the color requirements cannot be met by adjusting the amount of ink, and the hue of the ink of a certain color can be considered Appropriate adjustment, so that the printed product ink color meets the requirements of the original color. For example, when we print a four-color trademark at one time, the color of the light orange-yellow layout after overprinting has obvious reddishness, and the yellow hue has a feeling of obvious deficiency, which is quite different from the original color. The increase and adjustment of the Y color is limited, and it cannot be adjusted to the requirements of the original ink color. In this case, it seems that only by appropriately reducing the dot area of the M version and increasing the dot area of the Y version, can the effective Adjusting the effect of the color, however, is very labor-intensive, time-consuming, and increases the economic cost, which is not advisable. Through careful analysis and research on the printing samples, the author found that except for the overprinting relationship between the Y-color part of the flat screen and the M-color version of the flat screen, the M-color version has no single-color printing results, so , the author germinated in the "four-color red" ink, adding part of the "four-color yellow" ink to form a special spot color red ink for overprinting. To achieve a similar effect to the color of the sample, so that the printing color of the product finally meets the customer's requirements. In the same way, when printing a series of prints of different materials, the hue of a certain main color is often obviously lighter due to different materials. In this regard, it can be considered to appropriately adjust the ink hue of a certain color to achieve the printing ink color. It is also the easiest and fastest way to correct it.

Seven, use different printing process characteristics to control the printing color

Due to the difference in the printing process, the thickness of the ink layer of the printed matter is also significantly different. For a series of printed matter with large differences in materials, according to the adaptability of the printed matter layout color and material to the printing process, selecting a suitable process for printing is also to control the printing color. an effective way. The thickness of the ink layer of various printing processes is about: 3μm for offset printing; 8μm for embossing; 10μm for flexo printing; 12μm for gravure printing; 30μm for silk screen printing. Structure and other circumstances, consider selecting a printing process suitable for the ink absorption characteristics of the substrate material as appropriate. The offset printing process is limited by the balance of ink and water, and the adjustment range of ink coating amount is small, which is more suitable for printing substrates with relatively good gloss, such as coated paper, glass card, white card, offset paper, whiteboard paper, kraft card, etc. However, napkins are soft in texture, high in ink absorption, poor in tensile strength, and easy to stretch and deform. They are more suitable for printing with low-viscosity liquid water-based inks to obtain ideal printing colors, and water-based inks have great advantages in environmental protection. , so, using the flexographic process to print napkins is the best choice. The choice of printing process should not only consider the influence of the printing characteristics of the substrate on the printing color, but also consider the printing production cost, such as the high cost of gravure and flexo process, which is more suitable for printing long-term products.

8. Quality control method of different material series printed matter

Due to the limitations of the production scale of the printing factory, some factories only have a single flexo printing process, and some factories use a single offset printing process or gravure printing process. For many series of Jewelry Boxes, customers often send them to several factories for printing separately. . Due to the consideration of production costs, some customers do not use the proofing process. Often, the printing sample of a certain material is printed first, which is used as the color reference sample for the printed matter of another material. The control sample of the printing color of paper plates or coated paper cups brings certain difficulties to the printing color control, and it is often difficult for offset printing to keep up with the ink color of flexo printing. Because, the flexo ink layer is thick, and the adjustable range of the offset ink layer is relatively smaller than that of the flexo printing process. Therefore, when printing a series of prints with different processes, it is advisable to arrange the products using the offset printing process to be printed first, and then to use flexo printing, gravure printing or silk screen printing after printing, so as to facilitate the color control of the series of prints. If the offset printing process is also used to print products of different materials, it should be considered to print the materials with good gloss first, and arrange the materials with poor gloss to print later. Because of the material with good gloss, the control of the amount of printing ink is relatively accurate, which can reduce the chance of a large deviation of the printing color. It is worth mentioning that when using the printed manuscript as the control sample of the printing color, it is necessary to pay attention to the influence of the light transmittance of the sample manuscript material on the visual identification of the color. For example, the film printed matter and the napkin printed matter have high transparency and should be placed side by side with the printed sample. Identify on the stage.

In summary, to control the color of a series of Jewelry Boxes of different materials, it is necessary to pay attention to comprehensive consideration from the aspects of material characteristics, printing process technology and equipment operation adjustment, and through careful technical analysis of the original manuscript, and then determine the appropriate production process plan, so that It can not only avoid the blindness of the production process and reduce the occurrence of printing defects, but also better ensure the printing quality of the product and effectively improve the production efficiency.

https://www.minongpackaging.com/paper-box/gift-paper-box/custom-paper-jewelry-boxes.html