Application System
Continuous chemical impregnation systems apply liquid finishes, dyestuffs and functional agents to open-width fabrics through padding and expression rollers. Executing foulard finishing involves submerging moving fabric through a liquid trough before passing the wet web through rubber-covered squeeze rollers to enforce precise liquor pickup. The process applies softeners, water repellents, flame retardants and resin finishes across woven or knitted fabrics.
It operates in continuous wet processing ranges immediately prior to stenter drying or curing operations.
Impregnation Stage
Fabric webs enter liquid troughs containing dissolved chemical agents under controlled bath tension. During foulard finishing, uniform liquor temperature and concentration ensure equal chemical absorption across the fabric width. Submerged guide rolls submerge the dry textile web, driving trapped air out of fiber interstices to allow full chemical penetration into yarn bundles.
Pneumatic Pressure
Pneumatic or hydraulic squeeze rolls exert controlled nip pressure across the wet fabric sheet. Modulating nip pressure during foulard finishing controls wet pick-up percentage, ensuring consistent chemical add-on rates per unit weight of fabric. Uneven roll pressure causes shade listing or variation in functional finish performance across center and selvedge fabric sections.
Finishing technicians calibrate roll deflection and shore hardness to maintain uniform nip pressure.
Post-drying Check
Post-drying evaluation checks chemical add-on uniformity across fabric rolls. Foulard finishing parameters must achieve exact wet pickup targets without liquid migration. Inspection teams reject lots exceeding two percent pickup variation.