gassing
The process of passing cotton goods between two rollers and exposing them to numerous minute jets of gas to burn off the small fibres.
gassing: singeing fibers off fabric with open flame
Gassing is a finishing process in cotton and cellulose fiber textile production where woven or knitted fabric passes rapidly across the surface of a gas flame, or beneath jets of burning gas, to remove surface fibers and fuzz. The exposure is measured in fractions of a second. The goal is a clean, smooth fabric surface with better luster and reduced pilling tendency. The process is also called singeing.
In a typical gassing frame, the cloth moves horizontally at 50 to 200 meters per minute across an open flame or through aligned gas jets. The flame temperature sits around 1000 to 1200 degrees Celsius, hot enough to char cellulose fibers instantly but not to damage the bulk of the yarn when transit speed is correct. The fabric cools almost immediately in air or passes over a water-cooled roller, quenching any residual heat. Some installations use infrared heaters instead of open flame for better temperature control, particularly on delicate goods.
The process works because protruding fibers, loose fuzz, and neps (fiber knots) have high surface area relative to mass, so they ignite and burn away before heat penetrates into the yarn structure. Fibers that are already laid flat and well-integrated into the yarn survive. Tension and fabric weight matter: loose, open weaves show better results than dense twills, and heavy canvas may require multiple passes.
Failures and process control
Common faults include scorching, where the fabric surface yellows or becomes brittle from excessive heat or slow passage; uneven gassing, where flame jets clog or wear unevenly, leaving striped areas; and incomplete gassing, where speed is too high or flame too cool and fuzz remains. Gaseous combustion products, mainly carbon dioxide and water vapor, must be ducted away or the fabric emerges dirty. Flame flicker and air currents can cause patterned burn marks if not managed.
Gassing is essential for cotton shirting, lining fabrics, and lawn-weight goods destined for printing or dyeing, where surface cleanliness determines color evenness. Linen and wool are also singed, though less commonly in modern practice. The process sits between weaving and wet finishing, typically before scouring or bleaching. It is energy-intensive and produces fumes, so modern installations are hooded and vented to meet emission standards.