The print quality of prints performed with flexographic printing technology is influenced by various parameters such as viscosity of the printing inks, printing substrates, plates, anilox rolls, etc. The aim of this work is to analyze the influence of ink viscosity, printing plate and printing base on selected properties of print quality, such as optical density of full tone area and the increase of tonal value (TVI). Additionally, the printed dots on 5, 15, 30, 50 and 75% of half tone area were investigated using digital microscopy. The least square fitting method in a matrix form was successfully used in order to confirm the influence of printing process parameters on print quality. The results obtained reveal the significant influence of the printing plate and printing substrate characteristics and the lesser influence of printing ink viscosity for 40–100% coverage area. The values of the optical densities of full tone areas are mainly influenced by the properties of the printing plate and the printing base. Furthermore, the optical density decreases when the value of flow time decreases, which is related to the lower thickness of dried ink film. The TVI on light tones (0 to 20%) is mainly influenced by the ink viscosity.

The paper describes investigations on new method of the book cutting by using special circular knife with eccentric blade movement. Analysis of kinematic parameters of book block cutting shows, that by using eccentric circular cutting knife the cutting process may be realized in two different modes: continuous cutting – with the constant contact between cutting edge and cut material, and interrupted cutting process - with the impulse cutting knife action to treated material. The results of the conducted experimental studies confirm the kinematic analysis of the cutting process.

Structural scheme of models for determining the integral density of raster scale of an imprint, raster tone in percentage, optical density of scales on the basis of the measured optical density of the solid area and other characteristics have been worked out. The results of imitation design in the form of characteristics for different parameters have been provided. Optical density of raster scales obtained on the models has been found out to be quite similar to the results of experimental studies.

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A mathematical model of optical density of rasterized films has been improved, which has significantly increased the calculation accuracy of the optical density, especially at low intensities of the light areas of the image of 0-5%. The results of the simulation have been presented in the form of graphs of the optical densities characteristics for various parameters and their properties have been analysed.