In the field of printing, the transfer of inks is crucial to determine print quality and consistency. Ink transfer refers to the flow dynamics of the ink during transfer and application, which has a significant impact on the appearance and durability of the final print. This phenomenon can be quantified by the transfer rate, which reflects the efficiency of the ink movement at various stages of the printing process.
Types of ink transfer and influencing factors
Ink transfer in printing can be divided into two main situations:
(1) Ink transfer between ink rollers
The flow of ink between ink transfer, ink leveling and inking rollers is affected by factors such as ink viscosity, roller pressure and roller surface characteristics. Good transfer ensures an even distribution of the ink on the subsequent surface.
(2) Ink transfer between layout and substrate
This involves the transfer of ink from the plate to a substrate such as paper or cloth. Factors influencing this transfer include printing conditions (machine type, speed, pressure), substrate properties (surface smoothness, absorbency), and the nature of the ink (viscosity, viscosity).
Volcker and Fitzko's ink transfer equations
The Volcker & Fitzko Ink Transfer Equation is a fundamental model in printing technology that describes the transfer of ink during the printing process:
In this equation:
x: The amount of ink supplied on the plate in g/m² or μm.
y: The amount of ink transferred to the substrate.
b: Limit ink capacity.
f: Free ink splitting rate.
k: Printing smoothness factor.
This equation shows the ink transfer efficiencyY with B, F, and K are optimized, and these factors are affected by the surface smoothness of the substrate, the viscosity of the ink, and the printing conditions.
Effect of printing pressure on ink transfer rate
Printing pressure has a direct impact on the ink transfer rateπ, defined as the ratio of ink transferred to the substrate to the amount of ink supplied to the plate:
The experimental data show that the ink transfer rate π as the printing pressure P increases from the minimum Po to the critical pressure P2Increase linearly. After exceeding P2, the transfer rate reaches saturation, ensuring the stable quality of the printed matter. Excessive pressure P3These may result in distortion of the blot and distortion of the image.
Factors that affect ink transfer efficiency
Factors that affect ink transfer efficiency include:
Ink properties – viscosity and viscosity affect flow and adhesion.
Printing machine characteristics – roll curvature and width affect ink distribution.
Printing conditions – speed, pressure, substrate surface properties, etc.
Ways to improve the efficiency of ink transfer
In order to optimize ink transfer efficiency and obtain high-quality prints,Use of printing machines with appropriate roller configurations;Adjust the printing pressure within the appropriate range;Select a substrate with suitable surface properties;Make sure the ink viscosity matches the printing requirements.
Understanding the ink transfer process is important to optimize print quality. The Volcker & Fitzko Ink Transfer Equation is a key tool that not only helps us quantify and understand the flow of ink during the printing process, but also provides a framework for optimizing printing parameters for more efficient ink transfer. By controlling the amount of ink, the free ink splitting rate, and the print smoothness factor, the printing industry is better able to cope with a variety of complex printing needs and ensure the quality and consistency of printed matter.
