Problems faced by color newspaper printing technology

      At present, most domestic color newspapers are printed with newsprint. Compared with the general color printing industry printed with coated paper, its development time is short and the process technology is not mature, which is mainly reflected in the following aspects:

1. Lack of mature process technology theory and technical standards

      In the newspaper printing industry, monochrome printing has been used for decades. In the research on the adaptability of multi-color printing of newsprint with rotary offset press, there is a lack of systematic theoretical research results and guiding process and technical standards. It is difficult to achieve standardization and quantitative control in each production link and concrete evaluation on the quality of each process. Many technical parameters are difficult to obtain by experience accumulation in the production process, and must be completed by professional research institutions and personnel with the help of necessary testing means.Solutions To The Adaptability Of Color Newspaper Printing And Process Technology

2. No process management specification suitable for newspaper production characteristics has been formed

      The production process of color newspaper is very different from that of general color printing. Newspaper is a product with strong timeliness. The process flow of newspaper printing must comply with the overall requirements of newspaper publishing and distribution, which makes it difficult for the production process management of color newspaper to apply the ready-made mode of general color printing.Solutions To The Adaptability Of Color Newspaper Printing And Process Technology

      Therefore, it is necessary to establish process management norms suitable for the characteristics of newspaper production in order to achieve effective control of its production efficiency and quality. At present, this standardized management is still under exploration.Solutions To The Adaptability Of Color Newspaper Printing And Process Technology.

3. Lack of professional and technical personnel

      Most of the newspaper printing plants with the production capacity of printing color newspapers are equipped with more advanced multi-color rotary offset press and prepress equipment. The electromechanical integration and high automation of equipment put forward higher requirements for equipment management and operation team. Solutions To The Adaptability Of Color Newspaper Printing And Process Technology

     However, after the high investment in equipment, it is difficult for the newspapers to supplement the corresponding professionals in time. On the one hand, the original old staff need to adapt and learn the knowledge of color printing and improve the level of operation technology;Solutions To The Adaptability Of Color Newspaper Printing And Process Technology

      On the other hand, most domestic printing colleges and universities do not train talents for newspaper printing; Some printing houses transfer technical backbone from single sheet machine printing technicians to operate multi-color rotary machines. They also need a process of learning and adaptation. Solutions To The Adaptability Of Color Newspaper Printing And Process Technology

      Therefore, both experienced old employees and graduates trained by professional colleges are facing the problem of learning and adaptation in the process technology of color newspaper printing. It is a common feature of all newspaper printing houses that the cultivation of talents lags behind the transformation of equipment. After realizing the colorization of newspaper layout, a lot of work needs to be done to stabilize and improve the quality of color newspaper.Solutions To The Adaptability Of Color Newspaper Printing And Process Technology

4. The market’s requirements for the quality of color newspaper printing are constantly improving

      Although the color newspaper is just in the development stage in China, the market has used a higher standard to require it. The printing quality of color newspaper is not only one of the important channels for advertising publishing units to choose to release information, but also the embodiment of the strength of newspaper printing plants to undertake foreign business, which makes color newspaper printing integrated into the fierce market competition at the first step.Solutions To The Adaptability Of Color Newspaper Printing And Process Technology

      From the perspective of the overprint accuracy standard of four-color printing on rotary offset press, the overprint accuracy of color newspaper printing specified by the National Newspaper Association is less than 0.1mm-0.15mm, which has met the overprint accuracy requirements of coated paper sheet fed machine printing;Solutions To The Adaptability Of Color Newspaper Printing And Process Technology

       When many people do not understand that there are great differences between newsprint and coated paper, rotary machine and sheet fed machine printing in process technology and printing effect, they even use the proofing effect of coated paper to measure the printing quality of color newspapers, resulting in fierce market competition and users’ higher requirements for products, which has brought great pressure to the newspaper printing plants. While facing the pressure, all printing factories need to seriously study how to stabilize and improve the color newspaper printing quality, and explore the technical means to effectively control the printing quality according to the particularity of their process conditions.Solutions To The Adaptability Of Color Newspaper Printing And Process Technology

       Influence of technological conditions of color newspaper printing on printing quality

      In the case that newsprint is widely used in domestic color newspaper printing, the printing of color newspaper should first solve the adaptability of high-speed rotary machine to newsprint printing, understand and master its mutually adaptive characteristic range from the aspects of printing equipment, process management, operation technology and auxiliary media, and seek the control means to achieve the best printing effect.Solutions To The Adaptability Of Color Newspaper Printing And Process Technology

Characteristics of paper

      Newsprint is the main substrate of color newspaper printing. Mastering the characteristics of newsprint plays a leading role in solving the adaptability problem in each production link. The influence of paper performance on printing quality is mainly reflected in the following indicators.Solutions To The Adaptability Of Color Newspaper Printing And Process Technology.

① Whiteness

      The whiteness of paper is a numerical value indicating the optical performance of paper. It is a main index for color printing. Generally, the whiteness value of coated paper is about 85-100, while that of newsprint is only 50-60. The whiteness value of paper is high, the contrast between ink and paper is high, and the purity of color is high.Solutions To The Adaptability Of Color Newspaper Printing And Process Technology

      The whiteness of newsprint is not only much lower than that of other coated paper, but also the paper base has different degrees of gray and color deviation. Compared with printing on coated paper, the color gamut range and brightness of the same ink printed on newsprint are reduced. Affected by the reduction of contrast, the tone range and color reduction range are also shortened, and the hierarchical effect is bound to be reduced.Solutions To The Adaptability Of Color Newspaper Printing And Process Technology

 Surface smoothness

      The smoothness of paper is a value that reflects the surface finish of paper. The paper smoothness is different, and the contact between ink and paper in printing is different. Generally, the smoothness value of coated paper is 500-700 or even higher, while that of newsprint is only about 30-60. The surface of newsprint is rough, and ink imprinting on the rough surface will form small gap white spots, which reduces the density of ink and reduces the brightness of color ink. Solutions To The Adaptability Of Color Newspaper Printing And Process Technology

       Moreover, the paper wool is easy to fall off, making it difficult for large-area flat screen to print evenly, and small dot is easy to be lost. In this regard, only thicker network cables can be used in picture plate making, which not only reduces the clarity of the picture, but also difficult to show delicate hierarchical changes.Solutions To The Adaptability Of Color Newspaper Printing And Process Technology

 Ink drying method

      The performance of paper determines the drying method of ink on paper. There is a coating layer on the surface of coated paper. The drying of ink is mainly in the form of conjunctiva. The oxidation polymerization layer formed on the paper can not only maintain good saturation, but also have good luster and good color reduction effect. For the glossy coating layer on the surface of newsprint, the drying of ink is completed by appropriately penetrating into the pores between the paper fibers.Solutions To The Adaptability Of Color Newspaper Printing And Process Technology

      In high-speed operation, this penetration based inking method requires that the ink must properly reduce the viscosity and improve the fluidity. Under the pressure of the printing cylinder, the ink will penetrate into the paper and form different degrees of diffusion, so that the dot expansion rate is higher than that of coated paper, which will cause image dark tone, dot merging and even plate pasting, Thus, the level effect of image dark tone is reduced and the tone range is shortened.Solutions To The Adaptability Of Color Newspaper Printing And Process Technology

      From the main characteristics of newsprint used in color newspaper printing, compared with general coated paper, there are some differences in printing effect, such as poor image definition, small color reduction range, low color purity, small bright tone, easy loss of dot, easy combination of dark tone dot, small range of gradation level, and difficult to print evenly on flat screen.Solutions To The Adaptability Of Color Newspaper Printing And Process Technology