- Slides: 15
Basics of Textile Printing and finishing
Textile Printing • Textile printing provide fabrics with colorful designs as well as tasteful and appealing sceneries and patterns. • Printed fabrics are defined as those that have been decorated by a motif, pattern or design applied to the fabric after it has already been constructed. • Textile printing is actually localized application of color. • For printing textile fabrics the printing paste is made.
Screen Printing • A screen is made by covering a frame with a perforated sheet or mesh made up of cloth of silk, or metal or nylon filament yarns. • The mesh is covered with a film and the design areas are cut of the film. • Some areas of the mesh are left open to allow the dyestuff to pass through and print the fabric. • Flat-bed machine: Screens lowered onto fabric and squeegees force the printing paste through the screens.
Screen Printing • The frame is laid on the fabric, and the color is placed at one end of the frame. • A knife moves the colored paste across the screen and forces the dye through the open mesh of the fabric, • One screen is prepared for each colour. • Rotary screen machine: Screens are made into hollow cylindrical shape. • Fabric move under them and get printed.
Textile Finishing • Physical / Mechanical Finishing • Chemical finishing • • • Raising Calendering Embossing Heat setting Easy-care Flame resistant Stain resistant Water repellent Permanent pleating (resin)
Raising • HOW IS IT DONE? • The fabric is passed over rollers covered with fine flexible wire brushes which lift the fibres from the fabric to form a soft fibrous surface called a ‘nap’ • WHY IS IT DONE? • To produce a fabric with a soft handle, e. g pyjamas, dusters.
Calendering • HOW IS IT DONE? • Fabric is passed under heavy heated rollers under pressure. (The industrial equivalent to ironing) • WHY IS IT DONE? • To smooth the surface, • to improve lustre, • for embossed fabrics (embossed rollers) These are fixed with resin for cotton fabrics or heat setting for thermosetting synthetic fabrics.
Easy-Care • HOW IS IT DONE? • A resin finish is applied and cured by heat to cotton and viscose. • WHY IS IT DONE? • To make fabrics dry fast and need minimal ironing. However, it reduces strength and abrasion resistance
Flame Resist • HOW IS IT DONE? • A chlorine/phosphorous finish is applied and fixed. Can be applied to all fibres. • WHY IS IT DONE? • To reduce flammability of the product, However, it increases stiffness, reduces strength, adds cost and degrades when washed. Used for children’s pyjamas and upholstery.
Water Repellent • HOW IS IT DONE? • Fluorochemical resin is applied to face or back of fabrics. • WHY IS IT DONE? • To make them waterproof and windproof. Suitable for allweather wear, tents, shoes.
Permanent Pleating • HOW IS IT DONE? • Synthetic fabrics and blends can be heat set, Cotton and viscose requires a resin coating, followed by pressing and heat curing in oven. • WHY IS IT DONE? • To create permanent pleated garments that stay pleated when washed.
Soft finishes • Softeners are applied onto fabrics to make the fabrics soft. • They are usually oils and fats from plants and animal sources.