Opening and paper specifications

I. Concepts of opening data and opening data
It is usually called a fully-open sheet of raw paper split according to national standards. In order not to waste paper, facilitate printing and binding production operations, cut the whole paper into several smaller sheets with equal area, which is called the number of opening, and bind them into a book, which is called the number of opening.
For the text of a book, The number of openings is the same as the meaning of the book, but for the number of covers and plug-in paper, the meaning is different because of its area. Generally, the size of a single-page publication is called opening, for example, a newspaper or a wall chart.
Since there are several different series of international and domestic paper formats, although they are all split into the same opening number, their specifications are different. Even though the books are bound to different sizes. For example, the size of the current 16-open book is 188x265 (mm) and 210x297 (mm. In actual production, a full sheet of paper with a width of 787x1092 (mm) or 31X43 inch is usually called a positive paper, and a width of 889x1194 (mm) is used) or 35 × 47 inch of the whole piece of paper is called a large piece of paper. Since the 787 × 1092 (MM) paper was originally defined by China and is inconsistent with international standards, it is a non-standard paper to be phased out. Due to many reasons such as papermaking equipment, paper, and existing paper models in China, there is still a transitional stage for the new and old standards. the current size of the cutting specifications is as large as 16 to 210x297 (mm) large 32 Open 148x210 (mm) and large 64 open 105x148 (mm); positive: 16 Open 188x265 (mm), 32 Open 130x184 (mm), 64 open 92 × 126 (mm ).

Ii. Opening and opening of commonly used paper
1. raw paper size
Commonly used printed source paper is generally divided into two types: reel paper and Panel Paper.
According to the national standard (GB147-89) Reel width size: (unit: mm)
1575 1562 1400 1092 1280
1000 1230 900 880 787
Panel size: (unit: mm)
1400 m x 880 1230x1000 m 1400x787 M 1092 x m
900x1280 M 880m x 1230 900m x 1280 787m x 1092

M indicates the vertical direction of the paper.
Allowable Deviation: The width deviation of the reel is ± 3mm.
Size deviation of Panel Paper width plus or minus 3mm

2. Opening and opening of common paper
Generally, when you describe the size of the paper, the order of size writing is to first write the short side of the paper, and then write the long side. The pattern of the paper (that is, the vertical line of the paper) is represented by M, placed after the dimension. For example, 880x1230 m (MM) indicates a long grain, and 1230 m x (MM) indicates a short grain. When writing the print size, especially the books and periodicals, you should first write the horizontal direction and then write the vertical direction.
In order to easily fold books and periodicals into a book when binding books and periodicals, printing paper is attached as shown in 2-1, most of which are cropped in multiples of 2.

Figure 2-1 method for cutting whole sheets

The Uncut paper is called the whole piece of paper, and the width of the whole piece of paper after being folded and cut is called the split or half-open; the width of the split paper after being folded and cut is called the four-open; the width after the four-open paper is folded and cropped is called the eight-open ,....... Generally, in addition to the multiples of 2, the paper can be cropped according to the actual size. When the paper is not cropped in multiples of 2, the paper Opening Method in the vertical and horizontal directions can be divided into the forward cut method and cross open method.
The opening method refers to the opening of whole sheets in a single direction, that is, the method of vertical opening or horizontal opening, as shown in 2-2.

Figure 2-2 Opening Method

The cross-opening method refers to the opening method for the combination of full sheets of paper, as shown in Appendix 2-3. Cross-opening method is often used in the face of difficulties in opening method cutting paper.

Figure 2-3 cross-Open Method

In addition to the two paper opening methods described above, there is also a hybrid paper opening method, also known as the cutting method and irregular paper opening method, the whole sheet of paper is cut into two or more kinds of small sheets. The advantage is that it can make full use of the format of the paper as shown in 3-4, and try to use the paper as much as possible. The hybrid activation method is flexible and can be used as needed without a fixed format.

Figure 2-4 hybrid paper Opening Method

3. Common start
(1) A degree of paper (size of printed finished products, paper and paper):

(2) RA degree paper (general printing paper, after cutting edge, can get a degree of printing finished size ):

(3) SRA paper (used for bleeding print paper, which features wide width)

(4) B degree paper (between a degree of paper, mostly used for printed matter of larger finished size, such as posters ):

(5) C-degree paper (envelopes and folders used to encapsulate a-degree files )):