Discussion on related technologies of the hottest

Digital packaging printing is mainly used in the sample market, testing samples, sales samples, improved packaging, distribution products, packaging with different printing data and sales packaging in different regions of products

digital printing can save the expenses of waste products, logistics groups and inventories, and provide merchants with fast samples, sales products, market test products or product distribution trademarks or packaging, which saves 20% and 90% time compared with general printing. Digital printing can also provide packaging patterns for businesses in advance, and provide personalized packaging printing services for small shopping malls and personal stores. For example, coffee shops, cigarette shops, pharmacies and other special stores can use digital printing to design their own unique packaging

in the label printing market, digital printing has a certain market position. However, in the corrugated packaging market, digital printing has just begun, and the packaging and cartoon printing that are easy to deform are gradually maturing. In addition, compared with digital label printing, the application of digital packaging printing has not developed today, but its development prospect is beyond doubt

despite the limitations of digital packaging printing, its advantages and prospects are certain. This paper will discuss some related technologies of paperboard digital printing

1 digital packaging printing concept digital packaging printing has two explanations: (1) a kind of digital printing is used to print flexible packaging, comics, corrugated boxes and labels. This printing technology directly uses electronic documents to produce pictures and texts on the embossing cylinder. Such computer direct printing process omits the traditional film, plate and streamline printing process; (2) digital packaging printing is composed of digital workflow, which omits the steps between concept and printing of traditional printing. The digital printing mentioned here is to generate new graphics and texts on each embossing cylinder, that is, non-contact printing (NIP)

the field of digital printing is very extensive. If the materials allow, digital printing can be used for the packaging of all products. However, compared with general printing methods, digital printing is limited because of low productivity and large consumption in all aspects. For example, there will be problems in the printing of photosensitive substrates such as plastic. In addition, when users want to print on cardboard with a certain quality, its limitations are also reflected in the maximum load of the printing machine on the cardboard. From the perspective of R & D strength. At present, the maximum load of digital printing is 350g/m2, but it should be noted that the thickness and quality are not the same problem. Usually, cardboard is thicker and harder than paper

2 printing performance of paperboard in order to successfully complete packaging printing, it is very important for the printing of all types of paper to meet the basic paper handling standard. In digital printing paperboard (solid bleached paperboard SBB, high whiteness kraft paper, paper and liquid packaging paperboard LPB), how to improve the paper handling becomes the key

in the printing process, it is very important to determine the critical paper feeding factor through the observation of the operator. The performance of paper feeding, transmission and feeding in the printing process of digital printing machine should be judged by certain grade standards. In order to observe the possible damage and influence, the factors that need to be tested are thickness, curvature, surface roughness, tension and resistance. In addition, humidity loss, curl or unevenness are also factors that affect the printing quality

in digital printing on paperboard, the three most important factors affecting the printing quality are the curl, bending and unevenness of paperboard. The curling of paperboard will cause paper feeding problems and enhance the bending or unevenness of paperboard, which will cause product performance problems. In the paperboard transmission system, the paper feeding and transmission problems are caused by the curl, unevenness, inappropriate thickness and inappropriate printing size of the paperboard. Moreover, curl and unevenness are usually caused by the printing conditions of the printing machine, such as uneven printing and uneven exposure of the photosensitive layer

the consistency of paper cutting and paper feeding of the paper feeding unit is another problem of web printing. Uneven paperboard structure and machine pressure affect the problems of paperboard curling, unevenness and cutting. When the photosensitive substrate is exposed at high temperature, or due to the influence of different melting technologies, there will be varying degrees of humidity loss, curling and unevenness will occur, so the operator needs to pay more attention. When the bending toughness of paperboard is reduced, ensure that the reduction range is very small. However, dry and liquid toner technology does not have bending problems, unless it is web or sheet fed printing. In general, whether the sheet fed printer has good paper feeding performance, appropriate plane level and acceptable plane thickness, as well as the appropriate size of the printing photosensitive substrate, these properties can be achieved through adjustment

3 the influence of paperboard on the quality of digital printing. High quality printing quality is a very important factor that printing enterprises consider in the production process. When consumers buy goods, the primary problem they consider is the quality of images, which is as important as the price of products. Therefore, it is very important to ensure the printing quality of digital printing on electronic photography technology and liquid color agent technology cardboard (SBB, high whiteness kraft paper, LPB). The factors that affect the printing quality include contrast, gloss change, haze, particle shape, color balance, ribbon, etc

the important characteristics of paperboard with good printing quality are whiteness, transparency, flatness, gloss, humidity and wear balance. In addition, the paper is printed by dry toner Electronics (Kelu electronic transformation integrated energy service provider). In order to obtain good printing quality, it is necessary to control the humidity (ensure balanced ink transfer) and a smooth surface for melting. The use of liquid toner technology printing should have an appropriate amount of surface energy, good ink absorption and good surface energy smooth surface. The difference between the darkest and brightest images is the definition of illumination, such as TV images and oil paintings. Contrast is not only the difference between the maximum and minimum density, but also related to the hue of different levels of the image. Glossiness refers to the brightness and spectral reflection intensity of the surface. The difference of gloss refers to the gloss difference in spatial position. There are many methods to measure the gloss, but the paper should be measured under 75 spectral illumination, as shown in Figure 2. The most accurate visual measurement value can be obtained from this angle (tappit 480), and the measurement of high gloss paper and paperboard should be measured within 20 (t653)

printing ink spots are the spatial measurement changes in the uniform printing area, and the common printing and color blur. Large ink spots are blurred, and small areas of ink spots are speckles. Ink stain is a disadvantage of printing with random distribution, but it also has regular distribution, such as the increase of ribbon and stain. Regularly distributed ink spots are produced in the paper manufacturing process and printing process

speckle and small gloss difference can be calculated by analyzing the fringe image. When calculating the small photon difference, CCD camera should be used for drawing, and the calculation of speckle is carried out by scanner system. In both cases, the gray balance image should be calculated, and the calculation of speckle includes the calculation of reflection coefficient illuminated by stripes of different wavelengths. The testing of systematic printing ink spots, such as friction, color stripe and additional color spots, should be continuously analyzed, and the contrast between human visual system and paper texture should be considered

color balance is one of the criteria for judging excellent works, but sometimes printing products will have some special phenomena, such as color distortion. In order to get a standard color balance image, the observation of human eyes and the test of instruments are very important. The color of printed matter is measured by spectral scanner. The measured spectral data can be used for the calculation of density, CIE LAB and CIEXYZ

the key to the success of liquid and dry toner electronic photography technology is that the printing of paperboard and paper printing meet the same quality standards. The printing quality of different grades of solid bleached paperboard SBB corresponds to that of other paperboards. The poor printing caused by different paperboards is related to the properties of paperboards, such as humidity, surface properties, different printing machines, and the equipment and technical level of printing machines. Relevant important factors include the printing procedure and the nature of the paperboard, which are related to the preset printing quality. Taking into account the printing quality factors, reduce the level of color balance and contrast, on the premise that the factors considered should be judged by the standards of color management

the stains and gloss on the printed matter should also be graded, but each operator's observation between the paperboard and the printing machine is different. In order to obtain high gloss, when the photosensitive substrate is printed without glazing unit, the factors affecting the high gloss are the original gloss of the paperboard, the nature, density and melting temperature of the toner. For the surface polishing of printing products, high gloss can be obtained at high temperature

on some electrophotographic printing machines, relatively high humidity, high unevenness and paper unevenness in non printing areas will increase the haziness of prints. Moreover, different temperature conditions, melting technology and melting temperature, as well as the current transportation of toner and the thickness of toner layer are all factors that affect the quality of printed matter, and these problems should be further observed, studied and solved in the printing work. Low haze and graininess will reduce the gloss to varying degrees, because different gloss will produce varying degrees of haze and graininess on the surface of printed products

4 performance of finished products performance of finished products is the function of final packaging products. As a measure of the performance of finished products, its whiteness, the viscosity of toner, cracks at wrinkles, stains and smells should be considered. Good performance is that its whiteness is not affected by printing, the toner is well adhered to the surface of the plate base, and the crease of the corrugated paper does not crack the toner, and the color layer is free of stains. The viscosity of toner refers to the attraction between toner and base, which makes them stick together, which is explained in Columbia Encyclopedia. Usually, it will tear when cutting, including the crack line. Origami of paperboard printed matter is generally fully automatic

the adhesion of toner also depends on the roughness of the paper. Therefore, in order to improve the adhesion, it is necessary to have paperboards with different types of surface properties suitable for digital printing

in order to obtain high-quality printed matter, good contrast and whiteness of paperboard are very important. If the printing process reduces the whiteness or the requirements of the plate base, the white balance will change. White balance is the ability of the board base to maintain the whiteness of the board before and after receiving pressure. It is obtained by exposing the non graphic and graphic parts under natural light. Uncharged and a small amount of charged toner particles appear in the non graphic part of the potential electrostatic image, which will not affect the whiteness of the paperboard, but will affect the budgeted paperboard whiteness

ink spots are critical sensory properties observed at fixed points, which are inevitable

a small amount of volatile organic packaging materials, the domestic export market maintained a rapid growth in 2016