Soochow University describes an in-situ colouring route for bio-based nylon in its technical achievements overview. The approach introduces colour during polymer formation, bringing fibre manufacture and colouring into the same development process.
The overview is an institutional account of existing work. It gives no clear first-publication date for the technology, so it should be read as a technical profile rather than a newly announced launch.
Colour before downstream dyeing
The university describes low-temperature continuous polymerisation involving pigments and polyamide monomers, pigment modification and dispersion, and colour matching for coloured chips. It reports ultrafine filaments with a single-filament linear density of 0.4–0.8 dtex.
The stated purpose is to address pigment dispersion and colour-uniformity problems while reducing reliance on subsequent dyeing. The institution says the work has reached industrial application.
Reading the environmental figures
For each tonne of coloured nylon, the overview reports dyeing-stage reductions of 91.96 cubic metres of water and 2.47 tonnes of CO₂. These are project-reported figures. The page does not provide a full comparative assessment or the bio-based share of the finished fibre; the numbers should not be treated as a product-wide footprint.