What garment-dyed, piece-dyed and washed mean on a label

1 October 2026 8 min readApolyth

A label that says garment-dyed is telling you when the colour went in. Cloth can be coloured at almost any point between loose fibre and a finished shirt, and the point chosen changes how deep the colour sits, how closely one piece matches the next, and how much shrinking happened before you bought it.

Where the colour goes in

The European Commission's reference document on best available techniques in the textile industry lists the stages. Among them are "flock or stock dyeing" of loose fibre, "yarn dyeing", "piece (e.g. woven, knitted and tufted cloths) dyeing", and "ready-made goods (finished garments, carpet rugs, bathroom sets, etc.)". The list also includes top and tow dyeing, two forms fibre takes before it becomes yarn.

Stock dyeing colours the fibre before it is spun. Yarn dyeing colours the spun thread, and in the words of a 1997 US Environmental Protection Agency profile of the industry, the "dyestuff penetrates the fibers in the core of the yarn". It is used for woven checks, stripes and plaids.

Piece dyeing colours the cloth after it is woven or knitted, and it is the commonest route. The EPA notes that "Most dyed fabric is piece-dyed since this method gives the manufacturer maximum inventory flexibility to meet color demands as fashion changes." For continuous dyeing, it said, an economical run could need 10,000 metres or more per colour, though speciality ranges were being designed to run "as little as 2,000 meters economically".

Garment dyeing comes last. The garment is cut and sewn from cloth that has been cleaned and relaxed for dyeing, then dyed whole. Cotton Incorporated, which describes itself as "a research and promotion company" and is funded by US cotton growers and importers, gives the commercial reasons in a technical bulletin dated 2001: "rapid response to consumer demand" and "short lot dyeing".

What the dye bath does

Everything sewn into the garment goes in too. Cotton Incorporated recommends cotton thread, or corespun thread, which has a synthetic core wrapped in cotton, "so that the thread will dye to nearly the same shade as the garment". Where a garment combines all-cotton and blended fabric, the synthetic fibre in the blend "is left undyed". Different fabrics in one garment will show "some shade differences", which the bulletin says "should be minimal and often can be used as a styling advantage". Garments tumbling together can tangle, which "could cause resist marks or unlevelness".

The garment also shrinks in the bath. In trials reported in the bulletin, a knitted shirt whose fabric had not been finished for shrinkage control came out 22.3 per cent shorter. Trousers cut from mechanically preshrunk cloth shrank 1.3 per cent in length. The bulletin sets each figure beside the shrinkage of the same undyed garments after five home launderings and tumble dryings at 50°C, and they are close: 22.3 against 21.5 for the shirt. A maker can cut garments oversized to allow for shrinkage, "but seam appearance may be adversely affected." Why cotton shrinks at all is the subject of Why cotton shrinks, and what pre-shrunk does not promise.

Garment dyeing can also use far more water. The EU document's table gives liquor ratios, kilos of cloth to litres of dye bath, of 1:4 to 1:10 for fabric in a jet machine (in the EPA's description, a heated tube "where jets of dye solution are forced through" the cloth), and 1:60, "not exceptional", for garments in a paddle machine. Cotton Incorporated says paddle machines suit garments needing "gentler handling, such as sweaters", but "may limit shade reproducibility"; rotary drums, which run at lower ratios, have become more common.

Reactive dye and pigment

A reactive dye moves into the fibre and then bonds to it chemically. The EU document describes the fixing step as a "chemical reaction of the dye with the fibre to form a covalent bond", and explains what that buys: the energy needed to break the bond "is similar to that required to degrade the substrate itself, thus accounting for the high wet-fastness of these dyes." Wet-fastness is how well a colour survives washing.

A pigment does not bond at all. Pigment dyeing, in the EU document's words, is a process "in which an insoluble pigment, without affinity for the fibre, is deposited onto the textile substrate and then fixed with a binder". For garments, Cotton Incorporated describes three steps: a cationic, or positively charged, polymer first, so that the cotton attracts the pigment, then the pigment, then "a low temperature or air-curable binder, usually an acrylic-based product", to improve "fastness to rubbing or crocking". Crocking is colour rubbing off onto other things. Deeper shades rub off more, "even when increased concentrations of binder are used", while the pigments themselves have "excellent lightfastness". Cotton Incorporated's bulletin on pigment garment dyeing, written for the "weathered" or "distressed" look, says:

"The colors are intended to continue to washdown over the life of the garment."

Under the EU textile regulation, also law in Great Britain, binders and "additional dyeing and printing products" are among the items not taken into account in working out fibre composition. A pigment-dyed cotton shirt is a cotton shirt on its label, whatever is holding the colour to it.

Washed, enzyme-washed, stonewashed

For the weathered look, the same bulletin gives the general procedure as: "dye fabric in piece form, make-up garments, and then launder, washing down the color to produce the desired look." The word washed on a label does not say which wash.

An enzyme wash uses cellulases, enzymes that break down cellulose, the material cotton is made of. The EU document describes them removing "loose fibres adhered to the fabric", which "gives cotton a soft feel and reduces the pilling". It is just as plain about the cost: "Bio-polishing may reduce fabric strength and weight". There is no single figure. A 2024 laboratory study in Heliyon, from the Bangladesh University of Textiles, tried experimental enzymes extracted from waste sugarcane bagasse on 140gsm cotton jersey: bursting strength, the pressure a cloth withstands before it ruptures, fell by 3 to 11 per cent. A reference sample finished at a factory with a commercial acid cellulase measured 291 kPa against 294 kPa untreated, about 1 per cent lower, though the paper calculates no loss for it.

Stonewashing abrades denim with pumice stones in the wash to give what a 2023 review in ACS Omega calls the "worn-out look". Cellulase is now used in "bio stone washing", which "speeds up the abrasion process", and the review notes that "few grams of cellulase replace the kilograms of pumice stones", which reduces damage. Acid cellulases are the exception, causing "more fabric damage".

No label tells you which enzyme was used, for how long, or how much strength was spent.

What a label has to say

None of the rules below uses the words garment-dyed, piece-dyed or stonewashed. They are the seller's own description.

In the EU, and in Great Britain under the same regulation, textile products must be labelled or marked "to give an indication of their fibre composition" (Article 14). In the UK, the Digital Markets, Competition and Consumers Act 2024 prohibits misleading descriptions of products, and the Consumer Rights Act 2015 requires goods to be "as described".

In the US the label must give the fibre content, the maker's or seller's name or registered number, and the country of origin; the fibre-content rules are set out in What a fibre label is allowed not to tell you. None of it concerns dyeing, and anything else on the label "shall not be false, deceptive, or misleading".

The rule that comes closest to the dye bath is the Care Labeling Rule. If ordinary washing would harm the garment "or others being washed with it", the label must warn you. Its example is colour: "if a shirt is not colorfast, its label should state 'Wash with like colors' or 'Wash separately.'"

Sources

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