The printing ink additive is used as an auxiliary material for adjusting the ink to adapt to different printing conditions. Offset printing ink additives are many kinds, general commonly used withdraw of adhesive, scattered light agent, desiccant, desiccant, diluent, resistance to friction agent, cover the light oil, anti rubbed against dirty agent, inking oil etc., the following simple introduced common offset printing ink additives and usage; 

1: Samuel adhesives - adhesive with viscosity is very small, generally used for lithographic printing process and printing ink to reduce its viscosity. 

2: withdrawal of light agent - withdrawal of light agent, also known as dilution agent, is a relatively large amount of additives used in offset printing. There are two common withdrawal agents: one is transparent oil, for the light type ink; one is the resin type of light agent, used for resin ink. 

3: desiccant - commonly used desiccant with red dry oil, white dry oil two kinds, the drying of the red dry oil from the outside to the inside of the dry, white bath oil is the same time dry. 

4: Anti - Desiccant - also called antioxidants, which is relative to the desiccant of a kind of ink additives. 

5: thinner, in printing for printing ink viscosity too or poor quality paper, tend to produce paper szlama, off version of the fault, normal printing, at this time, in addition to adding the right amount of withdrawal adhesives to reduce ink viscosity and, addition of a small amount of thinner to reduce ink viscosity, so that the printing smoothly. 

6: anti friction agent, anti friction agent also called smooth agent, this kind of material mostly with a wax substance the, in printing ink particle coarse, such as white ink, ink and other, adding proper amount of resistance, increase printing resistance friction and smooth. 

7: cover light oil - trademark, pictures and other high-grade printing, the printing surface mostly through the hood light processing, to achieve high light effect, the use of varnish, in before printing the base mixed imposed on the ink, but also in printed matter printed together varnish. 

In addition to the printing should pay attention to matters; 

To transfer from the ink fountain roller. Ink in offset printing ink and the ink fountain roller always maintain good contact, in order to make offset printing ink evenly ink printing came. This depends on the rheological properties of offset printing ink: thixotropic cannot too big, yield value can not be too high, the viscosity can not be too small, wire head can not be too short, rheological property better. If ink and printing ink yield value high, viscosity is small, the ink on the difference, because it lacks the necessary of ink fountain roller adhesion ability, and so it must often dig the fountain, in order to ensure good contact between offset printing inks and ink fountain roller, otherwise it will for offset printing ink and the ink fountain roller gradually out of contact caused by printing of light. Also pay attention to the reserves of ink in offset printing ink, to be maintained within a certain range, and strive to ink uniform. 

Offset printing ink to avoid water ink high, ink layer too thick outward spreading dot enlargement and control 3% ~ 5% bright regional small dot is not lost, 5% of the halftone dot does not expand, stretching and darkened area 95% to 97% of dot and paste, ink quantity control standards for: figure and strong point clear, imprinted ink hue the premise of accurate, use less as far as possible the amount of ink. 

Offset printing ink has rigid, neutral, soft, three forms of the package, which is the best one? In offset printing ink can be said to have different characteristics and offset printing ink is an indirect way of printing, rubber roller intermediate elastomer plate graphic dot transfer to paper surface on, rubber reinforcing and lining material is offset printing inks in graphic transfer intermediary, no lining is no printing pressure, there is no indirect printing. 

Bubble phenomenon and the fracture of the ink layer. This ink layer due to the centrifugal force and the cavitation phenomenon, ink layer occurred tensile fracture, but due to the offset printing ink on the surface of the substrate with good wetting properties, part of the blot ink layer is transferred to the substrate surface. Imprinted ink layer is split in two, transfer in the substrate surface imprinting offset printing ink by capillary adsorption, continue to infiltrate into paper. For smooth surface, small absorbent substrate, imprinted offset printing ink layer can adsorbed on the surface of the substrate, mainly take fast on the surface of the substrate to the offset printing ink affinity, cache to the force between the offset printing ink and substrate molecules.