Digital Printing Standard Technical Parameter Selection

As a new printing method, digital printing takes the lead in the short-run, personalized market. In the process of rapid development of digital printing, it encountered a stone that could not be ignored on the road to growth, that is, the lack of a unified digital printing standard, so that the printing quality can not be measured correctly, but also led people to Misunderstanding of digital printing technology. Regarding the development of digital printing standards, many meetings have been held in China. However, it takes time for related standards to be issued. We know that the key issue in the formulation of digital printing standards is the selection of technical standards for printing standards and the establishment of data ranges. Based on the principle of statistics, this article statistically analyzes the technical parameters of the national standards for digital printing, tries to analyze the technical parameters of the digital printing national standards, and lays a foundation for the development of digital printing standards.

Data source analysis

The sample data of national standard technical parameters for digital printing is the basis for the development of the standard technical framework, and the data source must conform to both the basic laws of the existing printing standards and the technical characteristics of digital printing. From the indirect sources of data and the principle of direct sources, we can know that the combination of theory and practice to determine the digital printing technology parameters and range of values ​​is more in line with China's current printing standards.

From a theoretical point of view, digital printing is a simplification of the traditional lithographic, letterpress, gravure, and flexographic printing processes, and there are both connections and differences between these printing methods. Therefore, when formulating the technical parameters of digital printing national standards, it is necessary to select the technical parameters of the above methods and their values ​​as reference data. At the same time, these data can be used as a reference for the preliminary establishment of technical parameters. Passed existing printing standards such as International Standards (ISO), Chinese National Standards (GB), etc., including publicly published Chinese national standards "GB/T 7705-87 lithographic upholstery prints", "GB/T7706-87 letterpress prints" The "GB/T 7707-87 gravure upholstery printed matter" and other standard specifications, which can be related to the technical parameters as one of the sources of data.

From a practical point of view, by directly obtaining data from digital printing samples in actual production, the reliability of the theoretically determined range of technical parameters can be verified. As for its precise numerical value, a large number of observational experiments must be carried out to achieve optimization. The purpose of the data.

data collection

According to China's national standard "GB/T 7705-87 lithographic upholstery print", "GB/T 7706-87 letterhead upholstery print", "GB / T 7 7 0 7 - 8 7 gravure upholstery print" and "GB/T17497- In 1998, the composition analysis of the technical parameters of the flexographic upholstery printed matter was combined with the digital printing features. The printed products were described as two sets of fine print and general print respectively. Fine print refers to the use of high-quality printing materials and refined versions of the quality of the production process The high-grade printed matter of each index of the product; the general printed matter is the printed matter other than the fine printed matter.

Due to the different technical parameters of fine prints and general prints, the technical parameters of fine prints can be grouped with the technical parameters of general prints. This will be conducive to the scientific development of digital printing standards. The data can be divided into two groups: fine prints and general prints. After statistics, according to the description of each group of data and the need for further analysis, combined with the characteristics of the data (ie, technical parameters), the technical parameters and their values ​​needed to be classified again are summarized.

Since quality standards are the core of standards, in the field of printing, no matter which printing method is adopted, the key factors that affect the quality of printed matter must be concerned. At present, the key factors related to the quality of printed matter in the relevant printing standards can be summarized as the following three categories:

(1) Aesthetic factors

Prints are visual products. The aesthetic effect of prints is the key to the evaluation of print quality, including the choice of fonts, color design, art patterns, image positions, layout patterns, and selection of paper and ink. However, the quantitative description of aesthetic characteristics is extremely difficult, and generally only qualitative provisions are made.

(2) Technical factors

Technical factors are the controlling factors affecting the quality of printed products in various processes of printing production. The technical characteristics of print quality include image clarity, color, and the degree of reproduction of layers. Among these characteristic factors, most of them can be represented by numbers, such as color, tone, and registration.

(3) Consistency factors

Printing is a batch product and the consistency of the product is crucial. Due to the large number of variables in traditional printing methods, the consistency of print quality is critical. Although digital printing is very different from traditional printing production, consistency is equally important.

In the data description and analysis, the data of the above three types of factors are regrouped according to the four categories of color, level, clarity, and consistency.

data analysis

Through the existing national standards for fine prints and general prints, the highest frequency of several parameters: the same color density deviation in the field printing, the same batch of color difference, dot enlargement and overprint errors, etc., respectively, for fine and general digital printing products A large number of data collections were conducted, and the collected data were analyzed by scientific and mathematical methods, so that the approximate range of the national standards for digital printing was determined by the data obtained. However, because of the limited resources, there is no basic data collection for digital prints, and no data for analysis.

It must be noted that even if there are relevant proofs that can complete the collection of sample data and can obtain the data of the relevant parameters, because the statistical method cannot replace the law that fully complies with the practice of production practice, based on the description of the above technical parameters, the market digital is used. It is indispensable for a large number of prints to be verified. At the same time, the selection of technical parameters in the standard must meet the technical parameters that have been commonly used in the market.

Conclusion

It should be pointed out that the technical parameters listed above are based on the sample data of other printing method technical parameters and are based on the analysis of statistical principles. At the same time, during the formal establishment of digital printing national standards, technical parameters The selection of the range of values ​​also requires extensive and repeated testing. The method of selecting the parameters mentioned above is based on the statistics of the existing national standard parameters and can only be used as a reference for the selection of a parameter.

Printing standards are at different stages, people in the production of a rational elevation of practical experience, the digital age, in particular, we need to reflect the standards with rigorous, scientific data. Once the digital printing standard is established, the whole industry will benefit, no matter if it is a manufacturer, user or market. Therefore, it is urgent to establish a digital printing standard that meets the production requirements of China. However, the technical parameter selection method proposed in this paper is only through the author's existing standards at home and abroad. After the study was conducted, it was only used as a reference for parameter selection.

Reprinted from: the printing quality and standardization of: Fan Jinwen