Commonly used printing paper and classification
The printing methods vary, and the corresponding paper must be selected according to the requirements and characteristics of the use and printing process. The following are some of the commonly used paper specifications published, we refer to:
1. Letterpress paper
Letterpress paper is mainly used for letterpress books and magazines. It is suitable for texts such as important works, science and technology books, academic journals, and college textbooks. Letterpress paper can be divided into four grades of No. 1, No. 2, No. 3, and No. 4 according to the distribution ratio of paper materials. The paper number represents the degree of paper quality. The larger the number, the worse the paper quality.
Toppan printing paper is mainly used for relief printing. The properties of this paper are similar to those of newsprint, but they are not exactly the same. The fibrous tissue of the letterpress paper is relatively uniform. At the same time, the voids between the fibers are filled with a certain amount of fillers and rubber materials, and the bleached paper is also processed. This forms a good adaptability of the paper to printing. Its ink absorption is not as good as newsprint, but it has the characteristics of uniform ink absorption; water resistance and paper whiteness are better than newsprint.
Relief paper has a uniform texture, lint-free, slightly elastic, opaque, slightly water-resistant, and has a certain degree of mechanical strength.
Flat paper specifications: 787×1092, 850×1168, 880×1230; there are some special size paper
Web specifications: width 787,1092,1575
Length is about 6000m-8000m
Newsprint, also called white paper, is the main paper for newspapers and books. Applicable to newspapers, periodicals, textbooks, comic books and other text paper. The characteristics of newsprint include: light, light and good elasticity; good ink-absorbing performance, which ensures that the ink can be firmly fixed on the paper. After the paper is pressed, both sides are smooth and have no lint, so that the two sides of the print are relatively clear and full; there is a certain degree of mechanical strength; opacity is good; suitable for high-speed rotary printing.
This kind of paper is produced from mechanical pulp (or other chemical pulp) as a raw material, contains a lot of lignin and other impurities, and should not be stored for a long time. If the storage time is too long, the paper will become yellow and brittle, and the water resistance is poor, so writing is not appropriate. Must use printed ink or book ink, the ink viscosity should not be too high, the lithography must strictly control the layout of moisture.
Flat paper specifications: 787×1092, 850×1168, 880×1230
Web specifications: width 787,1092,1575; length about 6000m-8000m
3. Offset paper
Offset paper is mainly used for lithographic (offset) printing presses or other printing machines to print higher-level color prints, such as color pictorials, picture books, posters, color printing logos, and some advanced book covers, illustrations, etc.
Offset of offset paper according to the pulp material is special number, No. 1 and No. 2, No. 3, with single-sided and double-sided points, there are two levels of super calendering and ordinary calendering.
Offset paper has small stretchability, uniform ink absorption, good smoothness, close texture and opaqueness, good whiteness, and strong water resistance. Conjunctival offset printing inks and good quality printing inks should be used. The viscosity of the ink should not be too high, otherwise there will be powdering, pulling phenomenon. Also to prevent dirt on the back, generally using anti-dirty agent, dusting or insert liner.
Weight: 50,60,70,80,90,100,120,150,180 (g/m2)
Flat paper specifications: 787×1092, 850×1168, 880×1230
Web specifications: width 787,1092,850
Coated paper, also called coated paper, is made by coating a white paste on a base paper and calendering it. Paper surface is smooth, whiteness is high, paper fiber is distributed evenly, thickness is uniform, stretchability is small, there is better elasticity and stronger surface is smooth, whiteness is higher, paper fiber is distributed evenly, thickness is consistent, stretchability Small, with good elasticity and strong water resistance and tensile properties, very good ink absorption and receiving conditions. Coated paper is mainly used to print pictures, covers, postcards, exquisite product samples, and color trademarks. Coated paper printing pressure should not be too large, you should use offset printing ink and light ink. To prevent the back of the dirty, you can use anti-dirty course agents, dusting and other methods. Coated paper has two types of single and double sided.
Weight: 70,80,100,105,115,120,128,150,157,180,200,210,240,250 (g/m2)
Of which: 105,115,128,157 (g/m2) more imported paper specifications
Flat paper specifications: 648 × 853, 787 × 970, 787 × 1092 (currently no roll paper). 889×1194 imported copper paper specifications
5. Drawing a newspaper
The texture of the painting is fine and smooth, used for printing pictorials, atlases and posters.
Weight: 65, 90, 120 (g/m2)
Tablet size: 690×960,787×1092
6. Written paper
Written paper, also known as book paper, is the paper used for printing book covers. Written paper is pigmented in paper, with gray, blue, beige and other colors.
Weight: 80,100,120 (g/m2)
Tablet size: 690×690,787×1092
7. Embossed paper
Embossed paper is specially produced and a kind of cover decorative paper. The surface of the paper has a pattern that is not very noticeable. The colors are gray, green, beige and pink, and are generally used to print monochrome covers. Embossed paper ridges, the spine breaks easily when binding. The curvature of the paper during printing is large, and it is difficult to feed the paper, which affects the printing efficiency.