TC INVESTMENT

What are the characteristics and meanings of newsprint?

Newsprint, also known as white newspaper, is the main paper used for newspapers and books. Applicable to newspapers, periodicals, textbooks, comic strips and other text paper. The characteristics of newsprint are: the paper is light and has good elasticity; the ink absorption performance is good, which ensures that the ink can be well fixed on the paper. After calendering, the two sides of the paper are smooth and lint-free, so that the imprints on both sides are clear and full; it has a certain mechanical strength; it has good opacity; it is suitable for high-speed rotary printing.

Newsprint is produced from mechanical wood pulp (or other chemical pulp), which contains a large amount of lignin and other impurities, and is not suitable for long-term storage. If the storage time is too long, the paper will become yellow and brittle, with poor water resistance, and it is not suitable for writing. Printing ink or book ink must be used, the viscosity of the ink should not be too high, and the moisture of the layout must be strictly controlled during lithographic printing. Since the raw materials used are mainly mechanical wood pulp, which contains essential elements and impurities, the paper should not be stored for a long time, and it is easy to be damaged.

(1) Paper for printing newspapers and general books and periodicals. Usually made with more than 80% mechanical wood pulp and less than 20% chemical wood pulp. There are also bagasse pulp and bamboo pulp as the main raw materials. According to the different proportion of slurry, it is divided into No. 1 and No. 2. No. 1 newsprint has high technical indicators, good ink absorption performance and tensile strength, and is suitable for high-speed rotary press printing. Because the mechanical wood pulp fiber contains more lignin, the paper is easy to yellow and become brittle under the action of light, so it is not suitable for printing books and periodicals that need to be preserved for a long time. The finished product is basically roll paper, with widths of 1575, 1562, 787, 781, 765 mm and other specifications, and can also be cut into single sheets according to needs.

Worldwide, newsprint is used the most. Due to the development of newspaper printing from letterpress printing to offset printing, papermaking raw materials have also developed from general groundwood pulp (ie mechanical wood pulp) to thermomechanical pulp and chemical thermomechanical pulp. Bagasse pulp papermaking is growing in the sugar-producing regions of southern China. The improvement of the speed and the width of the paper machine is also the most common with newsprint: the speed of more than 1000 m/min is not uncommon, and the width is generally 6 to 8 meters; the maximum speed is 1500 m/min, and the width is about 10 meters. The quantification of newsprint is different internationally according to printing requirements: offset newsprint is generally 40 grams/square meter, and rotogravure newsprint is about 50 grams/square meter.

The traditional basis weight of Chinese rotary letterpress newsprint is 51-52 g/m2, and tends to be low, and the development specification is 48 g/m2 paper. After the founding of the People's Republic of China, the northeastern and southern provinces successively expanded and built a number of large-scale paper mills, and newsprint initially approached a balance between supply and demand.

(2) Refers to regular movable type printed newspapers, in English "newspaper", which appeared in the early seventeenth century and was translated as a synonym for newspapers in modern China.

(3) Commonly known as white newspapers, it is mainly used for printing newspapers, periodicals, books and periodicals with a large number of prints and a short service life, offset printing comic books and other publications.