There are many types of printed matter, and different printed matter often require the use of different types of paper. The varieties and specifications of some commonly used printing papers are introduced below.

1. Letterpress paper

Toppan paper is the main paper used for letterpress printing of books and magazines. Letterpress paper can be divided into four grades: No. 1, No. 2, No. 3 and No. 4 according to the different composition ratios of paper materials. The number of the paper represents the quality of the paper. The larger the number, the worse the paper quality. Letterpress printing paper is mainly used by letterpress printing machines. This paper has properties similar to, but not identical to, newsprint. Since the ratio of paper pulp and the tapping of pulp are better than newsprint, the fiber structure of letterpress paper is relatively uniform. At the same time, the gaps between fibers are filled with a certain amount of filler and glue, and have also been bleached, which forms The adaptability of this paper to printing. It is slightly different from newsprint. Although its ink absorption is not as good as newsprint, it has the characteristics of uniform ink absorption; its water resistance and paper whiteness are both better than newsprint. Letterpress paper has the characteristics of uniform texture, lint-free, slightly elastic, opaque, slightly water-resistant, and certain mechanical strength.

Weight: 49～60)±2g/m2.

Specifications of flat paper: 787×l092mm, 850×ll68mm, 880xl230mm; and some special size paper.

Roll paper specifications: width 787 mm, 1092 mm, 1575 mm, length approximately 60m to 80oo meters.

2． Newsprint

Newsprint, also called white paper, is the main paper used for newspapers, periodicals and books. The characteristics of newsprint are: the paper is soft and has good elasticity; it has good ink absorption performance, which ensures that the ink is fixed on the paper quickly; the two sides of the paper are smooth and lint-free after calendering, so that the printed imprints on both sides are better Clear and full; has certain mechanical strength; good opacity; suitable for high-speed web printing. This kind of paper is produced from mechanical wood pulp (or other chemical pulp) and contains a large amount of lignin and other impurities. Not suitable for long-term storage. If stored for too long, the paper will turn yellow and become brittle, with poor water resistance, making it unsuitable for writing. Newspaper ink or book ink must be used. The viscosity of the ink should not be too high. The moisture content of the page must be strictly controlled during offset printing.

Weight: 49～52) ±2g/m2.

Flat paper specifications: 787×1092mm, 850xll68mm, 880xl230mm.

Roll paper specifications: width 787mm, 1092mm, 1575mm; length about 6000~8000 meters.

3. Offset paper Offset paper is mainly used for lithographic (offset) printing machines or other printing machines to print higher-end color prints, such as color pictorials, albums, posters, color printing trademarks and some high-end books, as well as book covers, illustrations, etc. Offset paper is divided into three types: special size, No. 1 and No. 2 according to the pulp ratio. There are single-sided and double-sided, and there are two grades: super calendering and ordinary calendering.

Offset paper has small elasticity, uniform absorption of ink, good smoothness, tight and opaque texture, and good whiteness. Strong water resistance. Conjunctival offset printing ink and better quality lead printing ink should be used. The viscosity of the ink should not be too high, otherwise powder removal and fuzzing will occur. To prevent dirt from sticking to the back, anti-fouling agents, powder spraying or lining paper are generally used.

Weight: 50, 60, 70, 80, 90, 100, 120, 150, 180 g/m2.

Flat paper specifications: 787 × 1092 mm; 850 × 1168 mm.

Roll paper specifications: 787 mm, 1092 mm, 850 mm.

4． Coated paper

Coated paper is also called printing coated paper. This kind of paper is coated with a layer of white slurry on the base paper and pressed.

Made of light. The paper surface is smooth, the whiteness is high, the paper fibers are evenly distributed, the thickness is consistent, the elasticity is small, the elasticity is good, the water resistance and tensile properties are strong, and the ink absorption Sexual and receptive conditions are very good. Coated paper is mainly used for printing albums, covers, postcards, exquisite product samples, and color trademarks. The pressure should not be too high when printing on coated paper, and offset resin-based inks and glossy inks should be used. To prevent dirt from sticking to the back, methods such as adding anti-fouling agents and powder spraying can be used.

Weight: 70, 80, 100, 120, 150, 180200, 210.240, 250g/m2.

Flat paper specifications: 648×953 mm, 787×970 mm, 787×1092 mm

5. Painted newspapers are fine, white and smooth in texture and are used for printing pictorials, albums and posters.

Weight: 65, 91 and 12 g/m2

Flat paper specifications: 787×l092 mm.

6． Writing paper Writing paper, also called book cover paper, is the paper used to print book covers. Pigments are added to the paper when it is made, and it comes in gray, blue, beige and other colors.

Weight: 120g/m2.

Flat paper specifications: 690×960 mm, 787×1092 mm.

7. Embossed paper Embossed paper is a specially produced surface decorative paper. The surface of the paper has a pattern that is not very obvious. The colors are gray, green, beige and pink, and are generally used to print single-color covers. The embossed paper is brittle and the spine breaks easily when binding. When printing, the paper has a large curvature, which makes paper feeding difficult and affects printing efficiency.

Weight: 150~180g/m2.

Flat paper specifications: 787×l092 mm, 850×ll68 mm.

8． Dictionary paper Dictionary paper is a high-grade thin paper for books and periodicals. The paper is thin, strong and resistant to folding. The paper surface is white and delicate, the texture is tight and smooth, slightly transparent, and has certain water resistance. It is mainly used for printing dictionaries, classic books and other books with a large number of pages and that are easy to carry. Dictionary paper has high requirements on pressure and ink color in the printing process, so special attention must be paid to the printing process.

Weight: 30~40g/m2.

Flat paper specifications: 787×l092 mm.

9. Raw edge paper: Raw edge paper is thin, soft, light yellow, and hairless. Water resistance and good ink absorption. Raw-edged paper is only suitable for single-sided printing and is mainly used for ancient books.

10. Writing paper Writing paper is paper for writing with ink. The paper must not swim when writing. Writing paper is mainly used in factories to print exercise books, diaries, forms, account books, etc. Writing paper is divided into special size, No. 1, No. 2, No. 3 and No. 4.

Weight: 45, 50, 60, 70, 80 g/m2.

Flat paper specifications: 427×569 mm, 596×834 mm, 635×ll18 mm, 834×ll72 mm, 787×l092 mm.

Roll paper specifications: 787 mm, 1092 mm.

11. Typing paper Typing paper is a thin sheet of paper. The paper is thin and flexible. It is not required to have holes when typing, and it will not be scratched by the pen tip when copying with a hard pencil. Mainly used for printing documents, forms and multi-copy vouchers. Used as interleaving paper and printing and packaging paper in books. Typing paper comes in white, yellow, red, blue, green and other colors.

Weight: 20~25g/m2.

Flat paper specifications: 787×l092mm, 560×870mm, 686×864mm, 559×864mm.

12． Fengfeng paper is used in printing to print various copy books and printing and packaging paper.

Weight: 25~28g/m2.

Flat paper specifications: 787×l092 mm.

13． Corbett paper Corbett paper is thin and tough, suitable for printing multi-copy books; it is used in book binding to protect art works and play a beautiful role.

Weight: 17~20g/m2.

Flat paper specifications: 787×l092 mm.

14. Self-printed paper White plate paper has small elasticity, toughness, and is not easy to break when folded. It is mainly used for printing packaging boxes and commercial packaging sulfur lining paper. In bookbinding, medium-diameter paper (spine strips) or covers used for bound spines and hardcover books. There are special and ordinary, single-sided and double-sided. According to the bottom layer, there are two types: gray bottom and white bottom.

Weight: 220, 240. 250, 280, 300, 350, 400g/m2.

Flat paper specifications: 787×787 mm, 787×1092 mm, 1092×1092 mm.

15. Kraft paper has high tensile strength and is available in single gloss, double gloss, striped, and grainless, etc. Mainly used for packaging paper, envelopes, paper bags, etc. and printing machine drum lining.

Flat paper specifications: 787×1092mm, 850xll68mm, 787×ll90mm, 857×ll20mm.

Coated paper, commonly known as coated paper, has many types and can be used for printing a variety of color prints. The types of coated paper are as follows:

1. Single-sided coated paper: One side is coated and calendered, and the other side is glued. The two sides of the paper have different properties and are suitable for printing on both sides.

2． Double-sided coated paper: It is coated and calendered on both sides, the bottom side is shiny, has good dimensional stability, and is suitable for general color printing.

3. Special-grade double-sided coated paper: It is coated and calendered on both sides. It has a better gloss than ordinary double-sided coated paper and has a smooth and delicate surface. It is suitable for printing bright items that need to express a metallic texture.

4. High-grade snow-surfaced (matte) coated paper: coated and calendered on both sides, but the paper surface has low gloss and the powdery surface is not harmful to the eyes. It is suitable for printing non-reflective items such as reproductions of Chinese paintings and clothing fabrics, giving people a simple and elegant feeling.

5. Xinli 2000 special coated paper: double-sided coated twice and then calendered. It has good gloss and smoothness and is suitable for printing high-end color prints.

6． Embossed coated paper: Paper that is coated on both sides and then embossed. The paper surface has low gloss. Due to the embossing, the paper has a three-dimensional appearance. It is suitable for the reproduction of oil paintings, art advertising design and other color printing.

7. Lightweight coated paper: The surface is slightly coated and has better surface properties than uncoated paper. The quality is between coated paper and uncoated paper.

To meet different needs, lightweight coated papers include graphic paper, high-quality graphic paper, ivory Dowling paper, snow-white Dowling paper and magazine paper, etc.

(A) Pictorial paper: The surface is filled with a trace amount of paint to fill the gaps in the paper to improve the printing performance of the paper. The paper has high whiteness but low gloss, giving it an elegant feel. Suitable for color printing with higher screen lines than offset paper.

(B) High-end pictorial paper: In addition to being treated with a small amount of paint, the surface is also calendered. The paper surface is smooth and delicate, suitable for printing fine mesh paper prints. However, due to the unevenness of the paper surface after calendering The capillary pores are reduced, and it has the characteristics of ink-absorbing paper and high ink holding capacity.

(C) Ivory Dowling paper: The surface is micro-coated, the paper surface is soft ivory white, the texture is fine and smooth, it has good readability and gives people a sense of high-end. Suitable for printing books, high-end books and other printed matter.

(D) Snow-white Dowling paper: Micro-coated on both sides, the surface is smooth and white. It can be stored for hundreds of years without discoloration. It is suitable for printing high-end industrial and commercial diaries, books, magazines, etc.

(E) Magazine paper: The surface is coated and then calendered. The paper is thin and has high opacity. The gloss increases significantly after printing. However, because it contains groundwood pulp, the paper is more likely to turn yellow, so it is suitable for printing magazines, books and other printed matter.