The new adhesives for micro grains for inkjet application by Smaltochimica

In the last year, Smaltochimica has become the first company to perform industrial-level production of adhesives for micro grains for inkjet application.

These innovative and complementary additives are used in the digital decoration of ceramic tiles to extend the range of decorations that can be performed.

This has been made possible by two factors: the creation of a new digital department equipped with everything necessary to perform tests and specific measurements; and the longstanding partnership with some of the leading producers and suppliers of chemical products for the industry.

The products were developed through collaboration with inkjet machine manufacturers, most notably Projecta Engineering.

The new adhesives for grains and powders, which can be applied using conventional digital printheads, are liquid products with the following technical specifications:

• A solvent-based chemical nature that makes them compatible with the materials used on conventional printheads and printers;
• Suitable chemical and physical parameters for application with digital printheads (low, constant and Newtonian viscosity, adequate surface tension and absence of particulate guaranteed by a filtration procedure to 5 μm);
• Long drying times and high bonding capacity to ensure perfect adhesion of the dry deposited grains and powder particles;
• High jetting capacity, which allows the printhead to deposit the maximum permitted volume of product. This increases the deposited quantity and consequently extends the drying times and increases bonding strength.

As a result of digital application of adhesives for grains, tiles can be decorated with powdered vitreous materials according to clearly defined patterns that can be synchronised with the coloured decors, likewise applied by digital printing. This new family of adhesives, sold under the Digicol brand name, consists of various products.

All adhesives in the series are coloured with special organic tracers and filtered to 5 μm. Custom products can also be ordered.

The drying time and bonding strength are directly proportional to the quantity deposited. To increase this quantity, it is advisable to use high discharge printheads (such as the Xaar 1002 GS40) and if necessary to double the number of adhesive application bars in the ceramic inkjet printer.

Digicol 2891 was the first digital application adhesive to be used at an industrial level by an Italian ceramic company.