The technology of digital printing is very varied, and depends a lot on the formats and applications that you want to make. But let’s say that the technology that goes for the most today is the inkjet.

This segment is suitable for printers using different inks, different ways of moving the heads on materials or even moving the materials under the heads, different types of ink drying and different sizes of materials that can be “fed” to various printers.

We will omit for now the explanations on the different types of inks that exist, chapter that will also better define this topic of the newsletter, We concentrate instead on the types of machines and nomenclature that they have and which are distinguished precisely by being more or less suitable for different types of materials.

RollToRoll Printers: as the name suggests, this type of printer can print roll materials and return rolls of printed material. These printers start from minimum print sizes, such as 137cm and even less, up to 5 meters for machines currently on the market. These machines are used to print materials in rolls, such as adhesive films, “pvc” sheets (we will see the chapter of materials that are improperly called so), synthetic fabrics or natural origin, and almost everything that is born on roll. Usually they are printers that have a system of dragging the materials (for convenience we will call them average) that resembles a “squeegee” or down the line, on which a group runs with the press heads mounted, covering the unprinted part as they pass through each step and possibly also parts already printed, overlapping several printing steps. These printers range from resolutions and definitions of images now comparable to “photographic quality” to the point that some of them are actually used for photographic reproductions, even certified, others instead have capacities to produce volumes up to 500-1000mq per hour, obviously with “different” qualities. Materials must be planar and must be able to be pulled evenly under the rollers so that they do not wrinkle and/or wave which may touch the press heads.

Flatbed printers: they are usually formed by a table like that of a cnc, a point cutter, but where instead of a bridge with tools suitable for cutting, there is a bridge with a group of press heads. There are basically two types of flatbed: with moving media deck and fixed heads or, vice versa, with fixed floor and moving heads deck. The former occupy on average twice as much space as the fixed plan sisters but often have a higher quality relative to their productivity, the latter (somewhat more commercial) They take up less space but still retain an important quality even if a relatively lower productivity. The materials usually printed on this machines, as can be deduced from their conformation are materials in plates and not in rolls, more or less flexible, for charity, but not properly rolling and with a “rigid hand”. These materials must be uniformly “calibrated” and non-porous, both for printing purposes and for anchoring reasons by means of vacuum pumps at the floor. The productivity of some of these machines reaches 200mq/h but were produced machines that reached 2000mq/h with qualities suitable to make packaging like what you see in supermarkets.

Hybrid printers: they are printers that can print materials in roll and also in plate. These machines were created for commercial reasons rather than technical, to allow any operators to acquire with a single investment… It is evident that these machines have nominally lower performance than specialized machines, even if the technology has gone far enough on the market to produce some very good machines. There are two types: flatbed machines adapted to make also rolltoroll and rolltoroll machines adapted to print also rigid materials. The former have a plan usually completed with rolls of release and pick up of virgin material first and then printed, sometimes also with a “conveyor” (conveyor) plan accompanying the material in its transition, the second, roller rolls adapted to make rigid materials, mount planes in front and behind the rollers to slide the rigid materials to be printed when flexible media reels are not put into printing. The former are certainly more suitable for applications of rigid materials and useful in case of need to make flexible, while the latter are more suitable for making flexible and can produce also rigid. In the second case, but in all hybrids, the impossibility of attaching a medium to a plane in a certain and safe way, can create some embarrassment in being able to reposition always in the same point several printing passages or ink layers for the production of relief images or “materiche”, but also here the technology (and more often some valid operators) They have managed to patch up these applications as well.

Next time we will talk about inks and their “specialties”, how they are usually matched to different technologies and why.

I hope to have given you some ideas for reflection this time.

To the next.