Home > Knowledge > Content

what is offset printing

Jul 03, 2019

Offset printing is a kind of lithographic printing. It can restore the color, contrast and level of the original with high precision and clear. It is the most common paper printing method at present. Applicable to posters, brochures, brochures, newspapers, packaging, books, magazines, calendars and other related color printing.

Offset printing adopts full automatic pipeline operation, computer automatic control, printing tower drum rolling printing, transmission belt automatic transmission CD. In order to avoid mixing different kinds of discs, BASLERR2 is added to the input end to detect automatically. Offset printing is mainly composed of white background and four basic colors (black, blue, red, yellow) in different proportions to match a variety of printing colors. The depth of various colors depends on the length of exposure time, printing pressure and printing temperature. The longer the exposure time, the darker the color; the greater the printing pressure, the darker the color; and the higher the printing temperature, the darker the color.

Three principles:

1. Water-oil incompatibility

Chemically, the so-called principle of similarity and compatibility determines that water molecules with mild polarity differ from non-polar oil molecules in their polarity, which results in the inability to attract and dissolve water and oil. The existence of this rule makes it possible for planar printing plates to distinguish between pictures and blank parts and to conceive water use.

2. Selective Surface Adsorption

According to the different surface tension, it can adsorb different substances, which also provides a possibility for the graphic separation of lithographic offset printing.

3. Dot Configuration

Because offset printing plate is flat, it can not rely on the thickness of the ink to represent the level of the image and text on the printed matter, but by dividing the different levels into very small dot units that can not be perceived by the naked eye, it can effectively show rich image levels.


1. Offset printing has the characteristics of high efficiency, high quality and low cost compared with screen printing.

2. High efficiency. Offset printing adopts automatic flow-line operation, automatic color matching by machine, automatic monitoring by computer, fast speed, and can print 15,000 pieces per hour.

3. High quality. Computer fine-tuning, accurate color matching, high position accuracy.

4. Good color effect. Printing varnish, color luster, smooth surface, clear printing effect, not easy to fade.

5. Low cost. Offset printing uses drum printing with thin printing layer and less oil.