Printing equipment and equipment industry 1.2

Section 2 Production and Sales of Printing Paper

Paper and printing are one of the “four great inventions” in ancient China. Because of the paper, typography finds a light and inexpensive substrate, which can make the brilliant culture of ancient China into a book passed to the future generations; because of printing, paper can show its true value in people’s cultural life. It is hailed as one of China's "four treasures in China". In particular, the best product in Chinese hand-made paper, Xuan Paper, enjoys the reputation of “Paper Shou Thousand Years” in terms of its texture, flexibility, whiteness, fineness, and smooth quality. China Xuan Paper was highly valued by famous painters and painters. Dan Qing, made of Chinese painting and calligraphy art treasures is regarded as a treasure of the country.

Paper is one of the most important raw materials for the printing industry. Although papermaking was invented in China, but for a long time, China is mainly handmade paper production, but the machine papermaking industry started very late. In 1881, foreign companies established Tianzhang Paper Mill in Shanghai. In 1882, when the Chinese built the Guangzhou paper mill and began production in 1890, it began its own mechanism of papermaking in China. After nearly half a century of development, by 1936, the output of domestically produced machine-made paper and board reached 89,000 tons. At that time, the imported paper once reached 306,000 tons. During Japan’s invasion of China, in order to plunder Chinese forestry resources, some pulp and paper mills were opened in the northeast. By the 1940s, the highest year for China's machine-made paper production was 1943, when the output of machine-made paper and board was 165,000 tons. According to historical records, in 1932, the country’s annual output of hand-made papers had reached 366,000 tons, of which 70% of production was concentrated in four provinces of Hebei, Fujian, Zhejiang, and Hebei. In 1949, the annual output of paper and board of the National Mechanism was only 108,000 tons, and that of handmade paper was 120,000 tons. By 1992, the national annual output of cardboard was 172.570 million tons, ranking fourth in the world. In 1995, the output reached 28.1291 million tons, ranking third in the world.

I. Overview of paper production

1. Papermaking raw materials are mainly grass

Paper is not only an important raw material for the printing industry, but also an indispensable item for industry, electronics, science, education, business, and people's lives. The level of paper consumption has become one of the important signs to measure the progress of civilization in a country. According to statistics from 1982, in the production of machine-made paper and board, 22.1% of publishing and printing paper was used; writing paper accounted for 17%; packaging paper accounted for 15.6%; technical paper accounted for 2.5%; and packaging paperboard accounted for 31%. %; living and other paper accounted for 11.8%. According to the classification of the “Paper Industry Standard System Table” of the Ministry of Light Industry, paper and paperboard are divided into four major categories: 1. Printing paper and paperboard; 2. Culture, art paper and paperboard; 3. Packaging paper and paperboard; 4 Technical paper and cardboard. From this we can also see the status of paper in the national economy.

Paper is made from plant fibers made by papermaking. Since the beginning of this century, foreign countries have gradually developed wood pulp and papermaking, and China is a country with poor forestry resources. Taking into account China's large population, the potential market for paper consumption is broad, and at the same time, China's grass-like resources are rich in national conditions. In the early 1950s, the government established the direction of China's paper industry. The Second National Paper Industry Conference in November 1950 pointed out: "In the long-term, raw materials for the paper industry should be mainly wood pulp, supplemented by straw pulp.

However, due to the large-scale construction of large-scale pulp mills in the short term, the reserves of timber in China are not as good as they are ideally. However, the production of bamboo, bamboo and grass fibers has huge output. Therefore, how to effectively use bamboo and herbal fiber The construction of necessary pulping equipment is an important way to solve the problem of raw materials in the paper industry at this stage. "In the first five-year plan period, new batches of pulp and paper mills using timber as raw materials were built and expanded, such as Jiamusi, Guangzhou, Jilin and Yibin; new batches of Tianjin, Jincheng, Yingkou and Hanyang were newly built and expanded. Pulp and paper mills, which are raw materials, are not only paying attention to giving full play to the advantages of resources in different regions, but also trying to rationally distribute paper production and sales regions. After 20 years of development, the layout of China's paper industry The original northeast and east China regions gradually extended to south-central and south-western regions, with the development of the central and southern regions being the most prominent, and large-scale paper mills such as Yueyang, Ganjiang, Hanyang, Liujiang, and Guangzhou were all located in the Central South region. The annual output of the regional mechanism paper and paperboard accounted for only 4.0% and 4.6% of the annual output of the country, and it had risen to 22.79% and 8.70% by 1983. The National Paper Industry Development Plan for Ten Years (Draft) from 1958 to 1967 In the proposal, "Since 1958, non-wood fiber raw materials have been used as the main papermaking raw materials within ten years, and bamboo, bagasse, straw, straw, reeds, sorghum stalks have been tentatively identified. Corn stalks, cotton stalks, and waste fiber raw materials are the main uses and research objects. "The new plant has tried to limit the use of wood..." For decades, the amount of wood used in papermaking has increased with the increase in the output of paper and board, but it The proportion of papermaking raw materials has gradually decreased (27.5% in 1957 and 20.1% in 1982).

Although China's grass resources are abundant, they are widely distributed, and their quality and production are greatly affected by the regions and seasons, and they are difficult to concentrate. In order to meet the needs of large paper mills and certain varieties, the country also imports some wood pulp each year. Years of practice have led people to realize that if we want to fundamentally solve the problem of improving the quality of Chinese paper, we must change the structure of paper-based raw materials based on grass fibers. To this end, the Ministry of Light Industry issued a report to the State Council on the "6th Five-Year Plan" development plan for the papermaking industry on October 25, 1980, proposing a policy of "combining vegetation, raising the proportion of wood, and accelerating the construction of raw material bases." Since then, large-scale paper mills around the world have cooperated with forestry departments in afforestation and construction of raw material bases.

The history of paper for printing industry in China was developed under the principle of “grass-based” in the paper industry in China.

2. Publishing printing paper

(1) Letterpress paper for book printing.

Book printing is a "big family" of printing paper. Before the forties, printing paper was mainly imported newsprint, molded paper and brilliant paper. The news paper is subject to yellowing and brittleness for a long time. It is also because of the low degree of sizing, and the written text is easy to drown. The paper is thick and the price is high. It is not appropriate to make a large amount of printing paper for books and periodicals. The printing paper for foreign books and publications is wood-based lithographic paper and coated paper. Considering the lack of wood pulp resources in China, the country's situation is rich in reeds, rice straw, wheat straw, and other grass-pulp resources, and people’s cultural consumption is low. The Ministry of Light Industry is Before and after 1950, the two paper mills were first arranged in Tianjin and Jincheng, and a small amount of chemical wood pulp was used together with a small amount of chemical pulp to try to produce a new paper variety suitable for the text of the letterpress printing. It was called book paper at that time. Before and after 1953, the Ministry of Light Industry divided the book paper into five types: No.1, No.2, No.3 and No.4. It was officially named relief printing paper. Since then, letterpress paper has become one of the most important paper varieties in Chinese book printing paper, and this name has been used down. During the "1st Five-year" and "2nd Five-year" period, the state has successively built and expanded several paper mills, including Yingkou, Dandong, Hanyang, Yueyang, and Lancang River, specializing in the production of letterpress paper, together with Jincheng, Tianjin, and new constructions in the 1970s. Liujiang Paper Mill is known as the "Eight Great Letterpress Paper Mill." The letterpress paper produced by Jincheng Paper Factory won the 1979 National Silver Medal. In addition to the eight letterpress paper mills, there are countless small and medium-sized paper mills across the country that also produce letterpress paper. According to the statistics of the relevant departments in 1985, there are 341 sets of machine tools for letterpress paper made in China, including 86 sets of long nets, 44 short nets, and 211 round nets. The total annual output is 800,000 tons. Among them, eight large letterpress paper mills produce more than 200,000 tons per year, and other paper mill head netting machines total 400,000 tons, accounting for about 50% of the total production volume of Toppan paper. In other words, there are about 50% of letterpress paper produced by a rotary screen machine, which is of poor quality, and some of them have more paper defects. After strict selection, they can only be used on high-speed printing presses.

Table 25-3 National Production Statistics of Printing Paper

Note: 1. The figures in this table are taken from “China Light Industry Almanac” from 1985 to 1996. 2. Since the mid-1980s, the output of newsprint in newsprint has increased year by year. After the 1990s, the production of letterpress paper has been reduced, and plain printing has been reduced. The output of books and papers is increasing.

(2) Newspaper printing paper.

Newspaper printing paper is commonly called newsprint. Newsprint is mainly based on groundwood pulp, and Longnet produces reel packaging. During the period of “1st and 5th” and “2th Five-year Plan”, the state also built and expanded eight newsprint and paper mills in Jilin, Shiqian, Qiqihar, Yalujiang, Guangzhou, Nanping, Jiangxi, Yibin, etc., while building and expanding the eight letterpress paper mills. Known as the "eight major newsprint mills."

Newspaper printing is characterized by reeling, rotation, and high speed, which requires a high tensile strength of newsprint. Paper requires smoothness. Because newspapers are printed on both sides, they require newspapers to be more opaque. In order to meet the process requirements of newspapers in the printing process, the rapid penetration of ink, newsprint in the papermaking process does not add rosin and sizing, and over time, the paper will be yellow, brittle, which makes newsprint is not suitable Book printing is also not suitable for writing paper.

The production of low-quantity newsprint began in 1981. In October 1982, the Ministry of Light Industry held a seminar on the production of low-quantity newsprint at the Shiqian paper mill. The user evaluated the 49g square meters of low-quantity newsprint. After newsprint was changed from 51 gm to 49 gm, more than 3,000 newspapers were printed per ton. As a result, Shiqi low-quantitative newsprint won the 1982 Outstanding New Product Award from the Ministry of Light Industry.

There are more than 20 kinds of printing papers, but among them, the most used ones are the newsprint, letterpress and plain paper. In the 1980s, in order to meet the needs of the printing of books and periodicals, they also developed and produced plain printed books and papers. Table 25-3 shows the changes in the annual production of these four types of paper from 1949 to 1995.

3. Printing of newspapers, books and printing paper

The performance of printing technology and paper is not only mutually restricting but also mutually reinforcing. The poor performance of paper will affect the quality of the printed matter; on the contrary, the progress of printing technology will also drive the development of the paper industry. Since the 1980s, in the printing industry in China, as computer typing gradually replaced lead, the proportion of plain-printed newspapers and plain-printed books has increased.

With the printing of newspapers and books, in addition to the updating of platemaking equipment and printing machines, it is important to solve the problem of the printing of paper. The original newsprint was printed on a high-speed newsprint letterpress rotary press; the original letterpress paper was only suitable for a letterpress printer.

The surface of newsprint is basically not sizing; there is also less surface sizing on letterpress paper. The biggest feature of plain printing is that the paper is on the receiving cylinder