Anilox
Anilox is a steel measuring roller used for inking the flexographic stereotype. This process is called flexo printing.
In flexo printing a scratched or damaged anilox roll could cause printing errors. In worst cases it can even cause the interruption of the whole production process. To increase the lifespan of the anilox roll it’s necessary to adopt efficient cleaning procedures and accomplish them before the printing process.
The transfer volume is the volume of ink that will be transferred per unit area of the paper. The European standard for transfer volume is cm³/m² or cubic centimeter per square meter. For example, 1 cm³ of ink will be transferred into 1 m² of paper. The ink supplier could provide a recommended transfer weight per square meter, expressed in g/m². This value could be converted to cm³/m² by dividing by the ink density in g/cm³. The US standard for transfer volume is one billion cubic microns per square inch, written as BCM/in², BCM/sq in, or BCM. A cubic micron (μm³) is volume unit and one billion cubic microns (1,000,000,000 μm3³) are equal to 0.001 cm³. One square meter is equal to 1550 square inches, it follows that 1 BCM/in² is equal to 1.55 cm³/m².
The line count measures the renfinement of the anilox roll pattern. It calculates how many cells are carved per centimeter or inch. In Europe the standard is LPCM, or lines per centimeter. In US the standard is LPI, lines per inch. Converting from transfer volume to row count is not very simple. This because, depending on the pattern used for the cell and the engraving depth of the anilox roll, the cell may contain larger or smaller volumes of ink. The only way to convert cm³/m² (transfer volume) to LPCM (cell renfinement) or BCM to LPI is to look at the conversion chart provided by the anilox roll supplier. Please note that anilox roll could age after some time and its effective transfer volume is progressively reduced.
To extend the life cycle of the anilox rolls as much as possible it is necessary to clean the rolls with detergents every day. Otherwise, with solvent-based products, clean the rolls within a period from one to three months. It is also possible to run a hot chemical cleaning with alkaline washing products (such as caustic soda) or to run the sandblasting through cleaning powders. Another method is the ultrasonic cleaning combined with a detergent, or evaporation obtained by laser beams.
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