Digital printing: the green printing processBack
1 Why is digital printing considered more sustainable than traditional printing?
Digital printing sector is growing faster and faster, and both the machinery and the colors are constantly improving their performances and environmental profiles.
Digital printing is way more flexible and cost-saving than traditional printing: it allows print-on-demand, minimizes waste and by-products, and faster introduces new designs/patterns without needing cylinders or flat screens.
The production time is considerably shorter, resulting in energy and water savings.
The environmental impact of digitally printed textiles and garments is remarkably reduced.
But how can we control and deliver the highest print quality?
Many factors influence the final print quality: the complexity of the design, the substrate quality, the inks, and the process itself (printheads, process speed, etc. ) can improve or compromise the final result. Pre-treatment and post-treatment of the substrate are the key steps for an outstanding printing result.
First of all, we have to consider that the dyes tend to expand on the textiles, and thickeners cannot be added to the inks because they often strongly affect their rheological properties. Each fabric needs to be treated with a specific product before printing to obtain a specific penetration of the inks, avoiding image smudging.
A high-performance anti-migrating agent for the preparation of textile goods like our Mirox P- Ink (or Mirox CFP in case of pigment inks) allows to obtain a high definition of the printing with the same depth and brightness on the whole fabric width, avoids the migration of the dye during the drying, doesn’t affect the handfeel, improves the stability of the padding baths by increasing the viscosity and prevents residues formations on the guide rollers in the drying room. Finally, it is easily and completely removed from fabric by rinsing.
It's really important providing stability to the dyestuff, especially on cellulosic fibers (rayon viscose and cotton), by preventing the hydrolysis of the reactive inks through an anti-reducing agent like our Isopal GL powder: it prevents undesired color changes due to steam, high temperatures, and prolonged operation times and also acts as an oxidizing agent, stable in strongly alkaline conditions, obtaining regular oxidation of reducing dyes without over-oxidation.
In the end, if the printed fabric has been pre-treated, the drying time is reduced, and the fixation process is more efficient.
To obtain excellent fastness and brilliance, we need to remove unfixed dyestuff with specific auxiliaries like soaping, dispersing, and fixing agents.
ISOPON HDS PLUS is our highly biodegradable specific low foam washing-off agent for printed goods, very effective in removing unfixed reactive dyes, even in the presence of hard water; it allows a shorter post-treatment, unaltering the shades fastness and their brightness.
In the case of polyester fibres, ISOPON SPO is our dispersing agent for the PES reduction clearing step that improves the dyeing fastness prevents oligomers staining/depositing.
For pigments, when a proper fixation by padding is needed, FISSAT DFI improves the color yield and the crocking fastness values (wet and dry) and doesn’t affect the lightfastness.
All our products for digital printing have an outstanding environmental profile and are approved by the most relevant certification bodies.
If you want to know more about our digital printing range, download the full document here.