Classification of printing paper by different types

Printing paper refers to a kind of paper used for printing documents and copying documents. The standards are A0, A1, A2, B1, B2, A4, a5.

There are also according to the thickness of the paper, such as 60g, 70g, 75g, 80g, 85g, 90g, 100g, 120g, etc., which means that the weight of paper per square unit area is multiple. Since the density of paper is basically the same, the heavier the weight of paper per unit area, the thicker the paper thickness. For example, the speed printing machine usually uses 40g of paper, while the all-in-one machine uses 50-60g paper, while the copier uses 70-85g paper. The printer usually uses paper with a thickness of less than 60g, otherwise it will simply jam. For example: the weight of A4 paper is 70g / m2, not 70g of single paper. The practical weight of a piece of a4paper with a quantitative weight of 70g is: 0.210 × 0.297 × 70 = 4.3659 reference: (most of the work in southern and coastal areas uses 80g paper, while the inland and northern regions mainly use 70g printing paper.)

The computer printing paper used in needle printers of work automation series is classified according to the size and number of layers of paper, such as 241-1241-2. Their separation indicates that there are 1-layer and 2-layer narrow line printing paper, and of course, there are 3-layer and 4-layer printing paper; the commonly used wide line printing paper is 381-1381-2, etc. For example: 241-2 refers to carbon free printing paper (also known as pressure sensitive paper, computer printing paper, computer paper, etc.), which can only be printed on a needle printer. 241 stands for 9.5 inches, which is the width of the paper. This paper is also called 80 column printing paper (9.5 inches in width * 11 inches in height). In other words, in normal font, there are 80 characters in a line. The primary uses of these papers are: out / in bills, financial statements, air waybills, room bills, consumer bills, bank bills, express companies, supermarkets, hotels, KTV, outpatient department, wharf, air and sea transportation, etc.