Which anilox roller

The volume obtained, then, can be multiplied by the total number of cells on the roller to obtain the total volume of ink the roller can hold.

Or, typically, the volume of a cell is obtained, converted to cubic microns, and multiplied by the number of cells in a square inch. Another type of anilox cell structure is called a quad channel screen in which each cell is connected by a thin engraved channel. This type of cell structure has been found to have the most effective ink-transfer capabilities.

Cell wear is an important consideration, especially as a cell's region of greatest volume is at the surface of the roller. The fewer the total number of cells on the cylinder as a whole, the greater the percentage of the volume decrease. Wear is commonly gauged by the manufacturer, using a microscope. In practical application in the pressroom, a shinier roller surface or a decrease in print density of a known ink formulation are determinants of anilox roller wear. Anilox Rolls and Sleeves Share Print.

Anilox Rolls A common method used during the printing process is anilox -- when a measured amount of ink is supplied to a flexographic flexo print plate. Let the presses roll. Roll up your sleeves. How do I clean my anilox rollers? There are several methods and technologies that can be used to clean the anilox rollers: Manual Chemical cleaning method : Anilox rollers should be cleaned on a daily and monthly basis.

The rollers should be washed with chemical solvents after each retooling. Every months the rollers should be deep cleaned and scrubbed with a chemical cleaner that will penetrate the ceramic surface. Chemical cleaning Machine method : The anilox roller is treated with ink specific solvents then sprayed with heated chemicals which separate the binding agent from the ink.

Other cleaning agents are then used to dissolve the remnants. Anilox blasting technology : The anilox roller is dry cleaned by spraying it with a powder such as baking soda. The powder penetrates the cells, blasting off dried ink and other debris.

The powder is then washed off with water. Ultrasonic cleaning technology : The roller is rotated in a heated chemical solution in which ultrasonic sound waves are used to create gas bubbles. The gas bubbles implode on contact with the roller releasing pressure and temperature that dissolve and remove debris in the anilox cells. Hexagonal engraving. In mathematician Thomas C Hales proved that a regular hexagonal grid or honeycomb is the best way to divide a surface into regions of equal area with the least total perimeter.

The 60 degrees hexagonal pattern allows for more cells to be compacted in an area and provides the most efficient distribution of volume. There is less wasted space less land area if compared to diamond shape patterns traditional 45 deg. This is the reason, the most uniform distribution of ink of the 60 deg hexagonal engraving became the norm in flexo printing. However, the hexagonal 60 deg pattern has important limitations with regard to ink release and ink flow.

The 60 deg pattern consists of millions of individual hexagonal cells engraved across the surface of the Anilox roll. With closed-cell configuration air gets trapped with every rotation causing turbulence within the ink. This turbulence causes micro foaming and uneven laydown of ink to the plate and substrate. Micro foaming will be seen as pin holing in the print. Anilox Roll manufacturers have developed a number of alternative cell shapes to reduce this and a number of other issues often seen in fleoxgrahic printing.

At high speeds we always see a loss of colour density, this is caused by the inability of the closed hexagonal cells to fully refill with ink in each revolution. Poor ink release is another major restriction, due to its conical profile, the 60 deg. Problems arise when the unused ink congeals or dries, plugging the cells and causing print inconsistencies.

Things have moved on and todays advanced laser technology has enable Anilox suppliers to develop new engraving patterns that has surpassed the performance advantages of the conventional 60 degrees hexagonal pattern. In this article we will uncover them all and explain their main advantages and how they can help to bring the print quality in flexo to the same level of offset and gravure printing.

The great ink release properties of this engraving ensure enough volume is delivered to achieve high dense solids and extremely clean vignettes by keeping a high line count specification.

Depending on the type of substrate and ink system, the Anilox specification and engraving type might be different. Having well defined print targets with tolerances will enable your Anilox supplier to recommend the best Anilox specification for your particular print conditions.

The channel shape improves the ink flow and reduces aeration which results in significant less pin holing or absence of voids in the print which is the main factor that reduces measured ink density. This will not only produce finer graphics but also improve ink lay down of solid print areas which will have a smoother and more uniform appearance with less mottled coverage. Recent innovations in all press components continue to raise the bar in flexo printing, allowing converters to match or exceed the print quality of gravure and offset.

The demand for higher quality has seen HD Flexo becoming the new key driver within the flexo industry. Plate and ink technology in conjunction with the new Anilox screen developments have made this possible. The latest laser technology, as new fibre optics have enabled Anilox suppliers to engrave line counts in excess of LPI compared to the maximum of LPI by CO2 lasers.

The narrower beam width has made the dramatical increase in line count possible. The new lasers also come with custom software that provides the ability to manipulate and control laser engravings to unprecedented levels. This allows the Anilox supplier to custom design sophisticated cell shapes that offer outstanding ink release properties at ultra-fine line counts. The second factor has been the changes in ink flow and constitution.

The new finely ground ink pigments allow for greater colour strength at lower cell volumes. Advances in Printing Plate technology has played an important part as the new digital HQ or HD plates have allowed for an unprecedented refinement of the plate screen.

Before implementing this plate technology is crucial that the Anilox specification is considered for this technology to work. Your Anilox supplier will need to know the type of ink, substrate, plate DPI and target minimum dot percentage.

With this information, your Anilox supplier will be able to make a successful recommendation. Consistency and repeatability of HD process print are critical. ProFlo is a high performance engraving specifically designed for ultra-fine screen specifications. It has an improved cell profile that provides a more consistent and controlled ink lay-down to the plate, This high-release cell offers as much as 15 percent additional ink, compared with conventional 60 degrees engravings, enabling the Anilox manufacturer to produce an engraving that will deliver the required colour densities at finer line counts.

Keeping the Anilox cell opening equal to or less than the minimum dot diameter will ensure you can achieve the desired quality of clean printing. The line count and volume will be selected in relation to the aforementioned print parameters but for LPI HD print the most standardise line counts and volumes range from LPI to LPI with volumes ranging from 3.