letterpress paper is the main paper for letterpress printing books and magazines. Relief paper can be divided into four grades: No.1, No.2, No.3 and No.4 according to the composition ratio of paper materials. The number of paper represents the quality of paper, and the greater the number, the worse the paper quality. Relief printing paper is mainly used for relief printing machines. The characteristics of this kind of paper are similar to those of newsprint, but they are not exactly the same. Because the ratio of pulp and pulp are better than newsprint, the fiber structure of letterpress paper is relatively uniform, and the gaps between fibers are filled with a certain amount of fillers and sizing agents, and also bleached, which forms the adaptability of this paper to printing. Slightly different from newsprint, its ink absorption is not as good as newsprint, but it has the characteristics of uniform ink absorption; Water resistance and whiteness of paper are 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 ~ 6) 2g/m2.

specifications of flat paper: 787×l92, 85×ll68, 88xl23; And some paper with special size specifications.

specifications of the web: the width is 787mm, 192mm and 1575mm, and the length is about 6m ~ 8OOM.

2. Newsprint

Newsprint, also called white newspaper, is the main paper for newspapers and books. The characteristics of newsprint are: the paper is soft and elastic; Good ink absorption, which ensures that the ink is fixed on the paper quickly; After calendering, the two sides of the paper are smooth and lint-free, so that the prints on both sides are clear and full; Have certain mechanical strength; Good opacity; Suitable for high-speed rotary printing. This paper is made of mechanical wood pulp (or other chemical pulp) and contains a lot of lignin and other impurities. Not suitable for long-term storage. If the storage time is too long, the paper will become yellow and brittle, and the water resistance is poor, so it is not suitable for writing. Printing ink or book ink must be used, the viscosity of ink should not be too high, and the moisture content of the page must be strictly controlled during lithography.

weight: 49 ~ 52) 2g/m2.

flat paper specifications: 787× 192mm, 85x ll68, 88xl23mm.

specifications of web: width 787mm, 192mm and 1575mm; The length is about 6 ~ 8 meters.

3. Offset paper Offset paper is mainly used for lithography (offset printing) presses or other presses to print advanced color printed matter, such as color pictorial, picture album, poster, color printing trademark and some advanced books, as well as book covers and illustrations. Offset paper is divided into special number, No.1 and No.2 according to the ratio of pulp materials, with single-sided and double-sided, and with two grades of super calendering and ordinary calendering.

Offset paper has small flexibility, uniform ink absorption, good smoothness, compact and opaque texture, good whiteness and strong water resistance. Conjunctival offset printing ink and good quality lead printing ink should be selected. The viscosity of ink should not be too high, otherwise there will be powder removal and galling. It is also necessary to prevent the back from sticking dirty, generally using anti-fouling agent, powder spraying or interlining paper.

weight: 5,6,7,8,9,1,12,15,18 g/m2.

flat paper size: 787 ×l92; 85×1168 mm.

web specifications: 787mm, 192mm, 85mm.

4. coated paper

coated paper, also known as printing coating paper, is made by coating a layer of white paste on the base paper and pressing it. 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, and it has good elasticity, strong water resistance and tensile properties, and the absorption and receiving state of ink is very good. Coated paper is mainly used for printing picture books, covers, postcards, exquisite product samples and color trademarks. When printing coated paper, the pressure should not be too high, and offset printing resin ink and bright ink should be selected. To prevent the back from sticking dirty, methods such as adding anti-fouling agent and spraying powder can be used.

weight: 7,8,1,12,15,18,2,21.24,25g/m2.

size of flat paper: 648×953 mm, 787×97 mm and 787×192 mm

5. The texture of newspaper painting is thin and smooth, and it is used for printing pictorial, picture books and posters.

weight: 65? 6? Specification of 591 and 12g/m2

flat paper: 787×l92.

6. Written paper, also called book cover paper, is the paper used for printing book covers. Written paper is made with pigments, such as gray, blue and beige.

weight: 12g/m2.

flat paper specifications: 69× 96mm, 787×l92.

7. Embossed paper Embossed paper is a kind of paper specially produced to decorate the surface. There is an inconspicuous pattern on the surface of paper. The colors are gray, green, beige and pink, which are generally used to print monochrome covers. Embossed paper is brittle, and the spine is easy to break when binding. When printing, the paper is bent, and it is difficult to feed paper, which affects the printing efficiency.

weight: 15 ~ 18g/m2.

flat paper specifications: 787×l92, 85×ll68.

8. bible paper bible paper is a kind of advanced thin paper for books and periodicals, which is thin, strong and folding-resistant, white and meticulous, compact and smooth in texture, slightly transparent and has certain water resistance. Mainly used for printing dictionaries, classic books and other books with more page numbers and easy to carry. Bible paper has high requirements on the pressure and ink color in the printing process, so special attention must be paid to the art when printing.

weight: 3 ~ 4g/m2.

flat paper size: 787×l92.

9. Wool edge paper Wool edge paper is thin and soft, light yellow and hairless. Good water resistance and ink absorption. Wool edge paper should only be printed on one side, mainly for ancient books.

1. Writing paper Writing paper is paper for writing with ink, and the paper is required to be free from writing. Writing paper is mainly used for factory printing exercise books, diaries, forms and account books. Writing paper is divided into special number, No.1, No.2, No.3 and No.4..

weight: 45,5,6,7,8 g/m2.

flat paper specifications: 427× 569mm, 596× 834mm, 635×lll8 8mm, 834×ll72, 787×l92.

web size: 787mm, 192mm.

11. Typing paper Typing paper is a thin-page paper, which is thin and flexible. It is required not to pierce holes when typing, and it will not be scratched by the nib when copying with a hard pencil. Mainly used for printing documents, forms and multi-copy vouchers. It is used as spacer paper and printing and packaging paper in books. Typing paper has white, yellow, red, blue, green and other colors.

weight: 2 ~ 25g/m2.

flat paper specifications: 787×l92, 56× 87mm, 686× 864mm, 559× 864mm.

12. Youfeng Paper Youfeng Paper is used to print various carbon copies and printing and packaging paper in printing.

weight: 25 ~ 28g/m2.

flat paper size: 787×l92.

13. Cowper paper Cowper paper is thin and flexible, suitable for printing multi-copy copies; It is used to protect art works and play an aesthetic role in book binding.

weight: 17 ~ 2g/m2.

flat paper size: 787×l92.

14。 Self-made paper White paper has small flexibility and toughness, and is not easy to break when folded. It is mainly used for printing packaging boxes and commodity-filled sulfur-lined paper. In book binding, the spine used for wireless binding and the middle diameter paper (spine) or cover of hardcover books. There are premium and ordinary, single-sided and double-sided. According to the bottom classification, there are two kinds of gray background and white background.

weight: 22,24.25,28,3,35,4 g/m2.

flat paper specifications: 787× 787mm, 787× 192mm, 192× 192mm.

15. Kraft paper Kraft paper has a high tensile force, including single light, double light, stripes, no lines, etc. Mainly used for wrapping paper, envelopes, paper bags, etc. and printing machine cylinder lining, etc.