The article considers the physical meaning of the viscosity concept; physical quantities that are used to describe the viscosity properties of a fluid. The classification of viscosimetry methods for the printing industry is carried out. An analytical review of modern control and measuring instruments of ink viscosity used in flexographic printing process is implemented. The methods that are used the most in determining the ink viscosity are identified.
Capillary leakage is the most common method for measuring the viscosity of flexographic inks. Varieties of cup viscometers, their metrological characteristics, and shortcomings are considered. Rotary viscometers are also widely used in flexography. It is worth noting their ease of manufacture and use. According to metrological indicators, they have a wide range of measurements with an accuracy of ± 1%. They can be used both directly in ink tanks and in ink removal systems for measurement. The efficiency of using vibrating and electromagnetic viscometers in optimizing the process of determining the flexographic ink viscosity is studied. The prospects of using a new method for determining the viscosity on the dynamic pressure of the fluid are outlined. In the process of analysis of viscometers, their metrological characteristics are evaluated: range and accuracy of measurement. The advantages and disadvantages of using the considered viscometers to ensure the stability of high-quality flexographic printing are clarified.
The capabilities of modern processor technology make it possible to automate the process of control and regulation of ink viscosity, develop the latest methods of measuring parameters, improve the measurement accuracy and develop the automated viscosity assessment and maintenance systems to ensure quality flexographic printing products.
Keywords: flexographic printing technique, ink viscosity, gravimetric methods, rotary viscometer, vibrating viscometer, electromagnetic viscometer.
doi: 10.32403/1998-6912-2022-1-64-19-31
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