Black on gold - Israeli technology at its best

Black on gold - Israeli technology at its best

By: Shiri Rosen

Commercial printing of labels and packaging sometimes requires the use of printing metallic materials in order to produce particularly prestigious effects. How to do it, what the future of printing will look like and why one Israeli company brings us innovation and pride at Drupa 2016

Luxury products come in luxury packaging that sometimes includes metallic components: lettering, parts of an image, emphasis or areas that create a mirror effect. Since we are talking about the production of many covers - the commercial need for the production of printed covers of high quality, multiplicity and accuracy in colors (and materials) and at a very low cost. How is it done?

The technology of flexographic printers
Today most of the production of packaging and other industrial marketing materials is done by printing machines called flexographic printers. These commercial printers are able to print on a variety of materials - paper, transparencies, metal sheets and more. These printers mostly work by creating a plate with the pattern you want to print by exposing the plate made of light-sensitive material to the print pattern. Those components that the sample protected from the light harden and the rest are liquid - and this is how the board is obtained. The machine itself is made of several units that work one after the other where each unit includes a roll and is responsible for printing a single color. The roll of the printed material goes from roll to roll with each roll contributing its color layer to the finished product. The final print is obtained by mixing the colors printed in each of these passes. Large printers can even reach ten rolls and a very high accuracy of color and pattern. The color itself is hardened by exposure to UV light which fixes it, and another pass takes care of cutting the sample into the desired label shape.
You can see the process in the following video that demonstrates the process of creating cardboard boxes, the printing process at minute 03:13

Special techniques used by flexographic printers - elevation and metallography (use of metal)
There are several techniques that can give an extra touch to printing and create special elements. Among the common elements, for example, is the use of printing that includes embossing the printed model above the page (Embossing). This embossing can serve a variety of purposes from creating braille to giving the final print a luxurious feel. This elevation is achieved either by creating physical pressure on the printed paper or by using special types of ink that include materials that repel each other.
Another technique involves using metallic ink. The common metals used in prints are gold and silver, but other metals can be used to obtain additional shades, ranging from a metallic blue variety to a reddish shade of copper. In order to create these elements in printing, metallic sheets and heat are traditionally used. This melting of the metallic ink creates a rather thick layer that penetrates into the material on which it is printed and coats it. Common uses of this technique can create reflective or metallic-feeling surfaces on printed labels that impart a luxurious fragrance to the finished printed product.

Innovations in the world of metallography
In the upcoming exhibition of Drupa 2016, the leading exhibition for industrial printing technologies over a variety of materials, Landa is going to present innovative technology used for metallographic printing. The innovations include two components - the printing arm and the ink used.
The arm itself is adapted to be used as an add-on to existing flexographic printers, thus reducing the initial cost required to implement this technology. The second innovation includes the use of a special ink - Landa Nano-Flake Metal. In contrast to the traditional technology that uses metal sheets, only a very small part of which is ultimately used for printing and the vast majority of which is thrown away, in the new technology the new nano ink is created on a donor roll exactly in the pattern printed every time. The final result is the reduction of waste in the printing material because only and exactly the amount printed is used. The savings here are very large because in the traditional method only 0.01% or less of the material is used and the rest is thrown away.
In addition, since it is an ink with a thickness of less than 50 nanometers, the savings are twofold - not only the prevention of waste on the metal page in the donor material since the entire page is not used but only those printed parts, but also a measured and precise use of the metal page itself which allows for much cheaper printing while using in the minimum amount of material needed to create the metallic effect.
Using the new technology, it is possible to achieve a wide variety of metallic effects - including the creation of shiny reflective surfaces, flat or raised printing (Embossed) without the use of special ink, or the creation of shiny or other textured effects. Since metal flakes are used and not a continuous film, the printed product does not conduct electricity and is therefore also safe for use in microwave ovens.
The new arm types
Landa produces arms suitable for using the new technology for a wide variety of printing types - labels, folding cardboard packaging, flexible packaging materials, marketing materials and commercial printing. The new module replaces hot stamp and cold foil modules.
The new technology results in a significant saving of time and money in everything related to commercial and marketing metallographic printing. The technology results in the optimization of the process, the reduction of existing waste and the reduction of the schedules necessary for production and the reduction of the inventory required, all this while interfacing with existing printing processes or new printing presses. In addition, the simplicity of the process reduces the need for specialization in the whole issue of metallographic printing and exposure to new printing markets that until now have not used metallic materials either because of their high cost or because the product could not be used in microwave ovens.