In the plastic gravure printing, how to control the ink viscosity is a very critical problem. Especially in high speed rotogravure printing, such as temperature change ink printing ink viscosity control is appropriate, directly with the pigments transfer, dirty version, India product brightness, paint adhesion firmly degree, electrostatic and most quality problem is great, affect the yield of prints and efficiency. So, in the plastic gravure printing, how to control the ink viscosity, to take into account aspects, to ensure the quality of printed products. This requires us to first understand the ink viscosity and viscosity of these two concepts. According to the investigation of relevant materials or information, the overview of the relationship between the two is often vague, some even put both as a concept, in fact, between the two has a clear distinction, the following summary points to elaborate printing ink viscosity and viscosity difference and connection. 

1 temperature change ink definition is different 

If for some reason the outside world that different velocity of each layer of ink, especially between the two layers of surface flow speed of different liquid layer with force and counterforce exists, which the said ink internal friction, the nature of the show known as the viscosity of the ink. The physical quantity of ink viscosity is called viscosity. 

2 temperature variable ink performance 

Viscosity occurs when the ink film is separated, and the fluid is viscous, and the stationary fluid is not viscous. The effect of viscosity is shown to be the relative slip of the fluid inside the block, which blocks the flow of fluid, but the effect of this block can only slow the relative sliding process and not stop it. This is an important characteristic of fluid viscosity, and it is a rheological parameter, which indicates the internal adhesion characteristics of the fluid, etc.. The viscosity is measured by the internal friction force generated when the liquid is moved by an external force. Viscosity is a property of a fluid, whether it is at rest or in fluid, it always exists. 

3 temperature change ink detection methods, different units 

Viscosity is measured by a rotating viscosity meter. The resistance generated by the separation of ink or link layer is measured by the viscosity meter, and the numerical value is the viscosity value. No unit of viscosity. 

There are many methods for measuring viscosity. There is generally a capillary viscometer, hole type viscometer, rotary viscometer and rotary cone plate viscometer. Under normal circumstances, the use of rotary viscosity meter to measure the viscosity of ink. When the rotor is subjected to liquid viscous resistance, hairspring produces torque, and viscous resistance to compete, and finally achieve the balance, then connected with the gossamer pointer on the dial instructions must be reading (i.e., the torsion angle of the gossamer). The viscosity of the liquid is obtained by taking the readings to a specific coefficient. This shows that the viscosity and viscosity in different units. 

4 different influencing factors 

Viscous effects of factors: effect of elastic roller diameter, hardness and elastic modulus, and the nature, and the speed, and temperature, environmental temperature and humidity, sample temperature, ink film thickness, ink or links to material of elastic and, cleaning process for elastic and, character of the specimen to be measured. 

The factors to affect the viscosity: viscosity with temperature, particle concentration, particle size, etc. are closely related, and humidity and air pressure have little relationship, different measurement methods of measuring accuracy and measuring unit is different, can not be mutual conversion. 

We can see from the above four points, ink viscosity and viscosity are very different, but there is still a link between the two. Is mainly manifested in the viscosity is a measure of the physical quantities of viscous fluid size and the dynamic viscosity of the fluid is the amount determined by the physical properties of the fluid itself inherent, whose value is a viscous fluid size of a direct measurement and fluid in motion resist shear deformation is a measure of the strength of the. Under the same environmental conditions, the viscosity is large and the viscosity is large, and vice versa.