Characteristics of Textiles Colorants
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.
Grupo Denim is using the digital technology that offers opportunities to measure and monitor colours better during dyeing through the implementation of integrated colour management software packages, said Salomón Juan Marcos Villarreal, president of this company.