Water-based ink printing applications on corrugated cardboard

On the one hand, the anilox roller is the heart of the printing press and is a crucial part of the printing effect. It directly affects the effect of 1 ink layer; 2) drying and overprinting effects, which in turn affects the printing speed; 3) the constancy of printing quality; 4) the quality of graphic and text. On the other hand, the anilox roller is separated from the printing press supplier, and is supplied independently by a manufacturer who specializes in producing anilox rollers. The printing press supplier may be based on commercial reasons and cannot give too much advice to flexo printing manufacturers. Therefore, it is easy for manufacturers to choose the anilox roller. From the user's point of view, how can we properly choose Corrugated Packaging Machine anilox rollers to improve the quality of printing? This is a problem that most flexible printers are eager to solve. It is also a question that we want to discuss now. We hope that the Corrugated Box Machine following experience will help everyone. Now we will analyze the four aspects of the anilox roller aperture technology, ink and anilox roller, printing plate and anilox roller, flexible printing problems.

First, we talk about the most discussed anilox roller technology.

Before printing, the printer first needs to be clear about the tasks he wants to accomplish and the goals he wishes to achieve. This is the most basic condition for selecting anilox rollers. The parts we want to print are hierarchical printing, line printing, or both.

Next, we need to choose Corrugated Machine anilox rollers. We should use a 60-degree laser engraving ceramic anilox roller. HARPER's first 60-degree-angle anilox roll has now become an industry-accepted standard and it is believed that the best printing results can be achieved.

Here, we may wish to review the history of the anilox roller. The first generation of anilox rollers is a chrome plated roller (CHROME ROLL)

OPENING-cell opening (with ink area).

WALL OR LAND - Wall / Wall (without ink).

DEPTH-cell depth.

There are also CELL ANGLE-cell angles.

From the left half, we can see that the chrome-plated roller has an angle of 45 degrees and the mesh is diamond-shaped. This anilox roller has the advantages of good ink release and uniform mesh shape. But it also has insurmountable disadvantages: the number of anilox rollers is limited, easily damaged, and not environmentally friendly. The chrome roller didn't have a problem when it started to appear. But after the squeegee appeared, there was a problem. The surface of the chromium layer was quickly worn by the squeegee, and the net wall became unusually wide. Since the net wall portion could not carry ink, the amount of ink that could be transferred was greatly reduced. The wideness and the absence of ink on the net wall caused pin holes in the printed matter and Small white stripes, while bringing about problems such as insufficient color saturation. The lower right figure in Figure 1 is a schematic view of the worn chrome roller.

So people turned to use mechanically engraved ceramic anilox rollers. It is to spray a layer of ceramic on the surface of the mechanically engraved chrome roller. The anilox roller thus obtained has a longer life than the original chrome-faced anilox roller. However, the net wall is still very wide, the angle of the net array is still 45 degrees, and the mesh even has an irregular shape, and the release property of ink drops.

Then, a laser-engraved anilox roll appeared. Initially, they followed the precedent and still used a 45-degree angle arrangement. This greatly improves the quality of the anilox roll. But still can not get rid of the shortcomings of the wide wall. Until 1989, the United States HARPER Company first created a 60-degree angle network array, which has become the industry standard.

It is easy to find that the 60-degree anilox roller wall is thin, thus providing conditions for more stable ink transfer. The 45-degree anilox roller cannot be eliminated in the area circled in the figure. Therefore, there is still the problem of insufficient color saturation in printing. The shape of the cells on the 60 degree anilox roll is a regular hexagon, unlike the 45 degree rhombus. This is because the laser head travels in a different sequence during laser engraving.

The laser head first engraves 1-2-3-4-5-... After the completion of one week, the laser head walks one step, completes one more week, and then takes another step... until the engraving of the entire anilox roller is completed. From the figure it can be seen that to complete a standard hexagonal mesh laser, five steps are to be taken and all the six network points connected to it are completely engraved.

Therefore, we choose the anilox roller should have these features:

1. The correct mesh depth and opening ratio.

2. Thin wall.

3. Uniform engraving effect.

4. Good ink transfer ability.