Italdenim is switching all of its production to the chitosan-based processing system

Italdenim is switching all of its production to the chitosan-based processing system

Italian fabric specialist Italdenim is launching several new lines of eco-friendly denim that use a processing system based on chitosan, the vitamin-rich biopolymer found in the shells of seafood such as lobster and crab – and expects to switch all of its production to the technology this year.

The company, which is one of Italy's largest textile suppliers, has invested EUR4m (US$4.4m) over the last five years in sustainable technologies and processing techniques.

It was also the first denim manufacturer to adopt the chitosan-based processing system developed by Kitotex Canepa. The polymer is both organic and renewable, and is obtained by recycling crustacean shells that are currently tossed away at seafood restaurants and processing plants.

Chitosan can be used in the process of preparing yarns for weaving, by replacing PVA (polyvinyl alcohol) and acrylic resin for both water dispersion (sizing) and reinforcing yarn.

The Kitotex processes help reduce water consumption by up to 12 times and give a 90% reduction in energy consumption, according to Canepa – adding that chitosan also has a natural ability to bind dyes, reducing the consumption of these chemicals and cutting the use of detergents and bleaches and other products normally used during standard processing. It is also anti-pilling, anti-bacterial and anti-static.

Using chitosan at different stages of processing denim has enabled Italdenim to develop several lines of ecological products.

In blue denim, the chitosan is used as a natural fixer for indigo dyes instead of PVA, which is highly polluting and requires a significant amount of water for its disposal. PVA is a microplastic often found in wastewater even after intensive purification steps and is likely to enter the aquatic food chain.

Heavyweight bull denim uses chitosan to treat the fabric before dyeing, enabling savings of 30% on colour and chemicals, as well as offering the potential to provide special colours with fabrics in small quantities.

Chitosan is also used by Italdenim in place of acrylic resins to obtain special effects and finishes on denim, eliminating the presence of formaldehyde.

Italdenim, which signed up to the Greenpeace Detox campaign two years ago and is working towards eliminating all hazardous chemicals from its products by 2020, expects to process all of its products with chitosan by 2016.