Report Summary:
Developments in Textile Colorants |
24 pages,
published in Issue 127, January-February 2007 |
Textile colorants consist of dyes and
pigments for the coloration of yarns, fabrics and garments.
These colorants are applied either by dyeing or by printing.
In recent times, there have been a number of advances in
textile printing equipment, mainly in digital printing
methods. For example, digital printing is the fastest
growing system of all textile printing processes. Between
2000 and 2005, the output of digital printed textiles
increased by 300%. Some industry experts believe that
digital printing could account for 10% of the entire textile
printing sector by the early part of the next decade.
Innovations in printing and dyeing
technology have led to a number of changes in the textile
colorants sector, including shorter production times,
smaller batch sizes, lower production costs and improved
manufacturing efficiencies.
Also, in the past, dyers and printers have
found it especially difficult to color certain types of
fibres especially those made from synthetic materials such
as polypropylene, and fibres which naturally consist of
keratin, such as wool or fur. However, these types of
fibers can be treated with plasma gas before dyeing
to help the dyes to bond to the substrate. In printing, new
ink equipment such as valve-jet systems which are available
on J Zimmer Maschinenbau's ChromoJet 400 and 1200 enables
images or designs to be printed on to wool or fur without
loose fibres blocking up ink dispersion nozzles.
Perhaps one of the strongest drivers for
change is pressure for dyeing and printing methods to become
more environmentally friendly. The process of
electrochemical dyeing which reduces chemical waste and
decreases water wastage won an award for research and
development in 2006.
In dyeing, key technological advances
include: non-aqueous dyeing systems such as supercritical
carbon dioxide (CO2) dyeing; the use of ionic liquids;
electrochemical dyeing; cationisation; and plasma gas
treatment.
Digital technology offers opportunities
for companies to measure and monitor colors better during
dyeing through the implementation of integrated color
management software packages. Netherlands-based Stork
Prints, for example, has developed its own color control
concept to integrate the whole process. |