Wool detergent
A mild, near-neutral detergent without enzymes or bleach. What the wool industry body recommends, and what it recommends against is the more useful half.
In detail
A wool detergent is a mild, approximately neutral surfactant formulation from which two things have been deliberately left out. The first is enzymes: biological detergents contain proteases whose function is to cut protein molecules apart, and a wool fibre is a protein, so the enzyme cannot distinguish the stain it was added for from the garment it is in. The second is bleach of any kind. The wool industry body's guidance is explicit on both counts — avoid heavy-duty detergents, avoid biological detergents containing enzymes, and avoid any detergent containing bleaches, chlorine or oxygen based. What is left is a product that cleans by surfactancy alone at a pH that does not hydrolyse protein, which is the same design principle as a neutral stone cleaner arrived at from a completely different direction. Because wool washing is constrained on temperature and agitation as well as on chemistry, a wool detergent is usually paired with a long, cool, low-agitation cycle: the two variables the fibre cannot tolerate are traded for the two it can.
Properties
- pH
- Approximately neutral
What works
Wool detergent is effective against Grease Supported
Wool detergent is safe on, in specific conditions, Wool
Safe only in specific conditions
This is only appropriate within specific limits. Outside those limits, no claim is made.
Only within these limits:
- A mild or neutral detergent, with no enzymes and no bleach of either kind
- Wool cycle at 40°C, or hand wash at around 30°C
- Gentle agitation only — do not rub, pull or wring
- Dry flat unless the garment's own care claim states it may be tumble dried
The garment's care label governs. Machine-washability is a property of the individual garment rather than of wool.
Precautions
- Check the manufacturer's instructions
Evidence
Supported
Sources
Best detergent to use when washing wool
The Woolmark Company · Trade or professional body
Relied on for: That a mild neutral detergent is recommended for wool and that heavy-duty, enzyme-containing and bleach-containing detergents are to be avoided. (states this directly)
Wool care: how to wash wool, and caring for wool
The Woolmark Company · Trade or professional body
Relied on for: That wool is washed on a gentle wool cycle at 40°C or by hand at around 30°C, that garments should not be rubbed or wrung, and that drying flat is recommended unless the care claim permits tumble drying. (states this directly)
Wool detergent is safe on, in specific conditions, Wool
Safe only in specific conditions
This is only appropriate within specific limits. Outside those limits, no claim is made.
Only within these limits:
- A DILUTE solution, in TEPID water — not hot
- Blot or scoop the excess first with white tissue or an absorbent towel
- Work from the edge of the mark towards the centre, without rubbing
- For oily stains, only AFTER a solvent has been applied and allowed to evaporate
The wool body's stain method. The conditions are as much about order and technique as about the agent.
Precautions
- Test on an inconspicuous area first
- Check the manufacturer's instructions
Evidence
Strongly supported
Sources
The Woolmark Company · Trade or professional body
Relied on for: That treatment uses a dilute solution of approved wool detergent in tepid water, that excess is scooped or blotted first with white tissue, that the stain is worked from edge to centre without rubbing, and that oily stains take solvent first with evaporation before water-based treatment. (states this directly)
Why
- Wool detergent is explained by Surfactancy
- Wool detergent is explained by Enzymes in cleaning
Explained by the ABSENCE of enzymes: the reason this product exists is what has been left out of it.
When the obvious answer is wrong
What should I use on red wine spilled on a wool carpet or jumper?
Wool is a protein fibre and oxidising bleaches attack it directly, degrading the keratin rather than the stain sitting on it. The damage is structural and it is not a mark that can be cleaned off afterwards: the fibre is weakened, and on a carpet the affected area wears differently from everything around it. The wool body approaches this from the other side, warning that methods aimed primarily at cotton or synthetic garments are not all suitable for wool.
A different kind of treatment works: Change the mechanism from oxidation to dilution and dissolution, and respect the order. The wool body gives red wine, fruit and fruit juice their own entry and its sequence is three steps. First RINSE WITH CLEAN WATER — before any product, because wine is water-soluble while it is fresh and the cheapest removal happens then. Second, a DILUTE solution of an approved wool detergent. Third, and only where the mark persists, THREE PARTS SURGICAL SPIRIT TO ONE PART COLD WATER. Technique carries the rest and is stated for every entry on the page: scoop or blot the excess immediately with white tissue or an absorbent towel, work from the EDGE towards the centre, and dab rather than rub. Finish with a wash in an approved wool detergent. Where the label permits dry cleaning and the mark survives, tell the cleaner what the stain is AND what has already been applied to it — a treated stain is a different problem from an untreated one.
What should I use on a greasy mark on a wool jumper?
Wool is a protein fibre, and the mechanism that converts fat to soap also hydrolyses protein. A strong alkali therefore attacks the garment on the same chemistry it uses on the stain, and the damage is to the fibre rather than to its appearance — it is not a mark that can be cleaned off afterwards. The wool body approaches the same problem from the other end, warning that methods primarily aimed at garments made from cotton or synthetic fibres are not all suitable for wool, and specifying a dilute wool detergent in TEPID water rather than anything stronger or hotter.
A different kind of treatment works: Change the mechanism from saponification to dissolution, and respect the order. The wool body's instruction for oily or greasy stains is that they are best treated with SOLVENTS FIRST, and that the solvent MUST BE ALLOWED TO EVAPORATE before any water-based treatment is subsequently carried out. That waiting step is the part most likely to be skipped and it is stated explicitly. The water-based stage that follows is a dilute solution of an approved wool detergent in tepid water — dilute rather than strong, tepid rather than hot. Technique carries the rest: scoop or blot the excess quickly with white tissue or an absorbent towel, work from the edge of the mark towards the centre, and do not rub. Where the mark survives that, the honest next step is professional cleaning rather than a stronger alkali.
Sources for this page
Sources
Best detergent to use when washing wool
The Woolmark Company · Trade or professional body
Relied on for: That a mild or neutral detergent with a relatively neutral pH is recommended for wool, and that heavy-duty detergents, enzyme-containing biological detergents and any detergent containing bleach should be avoided. (states this directly)