'Fizzy water' dyeing process attracts funder
SwitchDye, a recent University of Leeds spin-out, has completed its first investment round with chemicals company John Hogg Technical Solutions becoming a “significant minority” shareholder. This move builds on an earlier investment by the Manchester-based solvent dye specialist when it acquired Avocet Dye & Chemical Company in 2024. Through this partnership, John Hogg has said that it will provide manufacturing expertise and access to its customer networks to help SwitchDye move from lab to mill.
The start-up has developed a low-impact dyeing process for synthetic fibres, and notably polyester, using carbonated water and existing machinery. The addition of carbon dioxide is said to “trigger the dyes’ unique switching behaviour within the polyester fibres”. The method is also said to require fewer auxiliary chemicals, reduce rinsing stages and work faster than conventional methods. Additionally, the dyeing process is reversible, making it possible to eventually remove colour from a product to facilitate recycling. The company claims that it uses 90% fewer chemicals and 40% less water.
The concept was first invented by Professors Richard Blackburn and Chris Rayner at the Schools of Chemistry and Design and the SwitchDye technique itself was developed by Dr Nathaniel Crompton as his PhD project.
