Finishes: definition and classification
A finish is any treatment that changes a fabric's look, feel or performance after it is made. Finishes are classed by permanence, method and purpose.
What a finish is and why it is given
Fabric straight from the loom or knitting machine is called grey (greige) goods: dull, dirty with oils and size, often harsh or limp and uneven. A finish is any mechanical or chemical treatment given to fibre, yarn or (usually) fabric to improve its appearance, hand (feel) or performance. Finishes are given to clean and whiten cloth; to improve lustre, smoothness or softness; to add body or stiffness; to control shrinkage and wrinkling; to add special functions such as water repellency, flame resistance or germ resistance; and to make cloth more saleable. Finished cloth is called converted goods.
Classification of finishes
| Basis | Class | Examples |
|---|---|---|
| Permanence | Permanent: lasts the life of the fabric | Mercerizing, heat-setting of synthetics, embossing on thermoplastics, sanforizing |
| Permanence | Durable: lasts most of the fabric's life, weakening slowly | Resin wrinkle-resistant and durable-press finishes, many water repellents |
| Permanence | Semi-durable: lasts several washes or dry cleanings | Some glazed calender finishes and flame retardants |
| Permanence | Temporary (renewable): lost in the first wash | Starching (sizing), simple calendering of cotton, bluing |
| Method | Mechanical (physical) | Tentering, calendering, napping, shearing, sanforizing |
| Method | Chemical | Scouring, bleaching, mercerizing, sizing, resin and water-repellent finishes |
| Purpose | General (routine, preparatory) | Singeing, desizing, scouring, bleaching, tentering |
| Purpose | Aesthetic (change look and feel) | Calendering, napping, sizing, embossing, moiré, softening |
| Purpose | Functional (special, performance) | Sanforizing, mercerizing, wrinkle-resistant, water-repellent, flame-retardant, mothproof, antimicrobial |
Where dyeing and printing fit
- Colour is usually added between the preparatory and final finishes, so some books study dyeing and printing alongside finishes.
- Dyeing can be done at the fibre, yarn or fabric (piece) stage. Yarn-dyed checks such as gingham, and resist-dyed ikat (Pochampally, Patola, Sambalpuri), are dyed before weaving.
- Resist methods on cloth: bandhani (tie-and-dye) of Gujarat and Rajasthan, and batik (wax resist).
- Printing: hand block printing (Bagru, Sanganer), screen and roller printing. Kalamkari of Andhra Pradesh is hand-painted with a pen (Srikalahasti) or block-printed (Machilipatnam), using natural dyes.
Activity: report on the utility of finishes
- 1Collect pairs of samples, finished and unfinished where possible: mercerized and ordinary cotton thread, starched and washed cotton, napped flannel, glazed chintz or embossed cloth, a Sanforized shirting and an unshrunk cotton.
- 2★Test each simply: rub test for sizing (powder falls out), water-drop test for absorbency (seconds to soak in), lustre by eye, and a shrinkage test (mark, wash, re-measure).
- 3Record results in a table: sample, finish, test, observation, utility to the user.
- 4Explain the utility of each finish for appearance, comfort, care and durability, and say whether it is temporary or permanent.
- 5Conclude with the finishes a homemaker or an institution should look for on labels, e.g. Sanforized, mercerized, wrinkle-free.
★ one-way, controls the pace
For hospital and kitchen textiles, prefer permanent or durable finishes (Sanforized, mercerized) over temporary ones such as heavy starch, which washes out in the first laundering and can hide a thin, weak cloth.
2 marks: “Define finish.” A finish is any mechanical or chemical treatment given to fibre, yarn or fabric to improve its appearance, feel or performance, e.g. mercerizing, sanforizing.
5 marks: “Classify finishes based on permanence, with examples.” Permanent (mercerizing, heat-setting), durable (resin finishes), semi-durable (some glazes), temporary (starching, simple calendering); one line each.
10 marks: “Define finishing. Explain the purposes and classification of finishes with examples.” Define finish and grey goods; purposes; classification chart by permanence, method and purpose with examples; note on colour application.
Three ways to classify, P-M-P: Permanence (permanent, durable, semi-durable, temporary), Method (mechanical, chemical), Purpose (general, aesthetic, functional).