Wednesday, 05 December 2018 13:43

Wool&Delicate and the wool felting problem

Felting is a process that leads to a change in the structure of wool fibers, difficult to reverse.
The causes can be varied, but do not worry! HygienFresh has the perfect solution!


Wool is a natural fibre of animal origin which comes from the sheep, rabbits and camel wool.
Among the different types of wool we can list the most famous and appreciated: Cashmere, Angora (which comes from rabbit), Merino and Alpaca.


from left: cachermire, angora, merino and alpaca

Wool chemistry

Wool is composed of a very particular protein: keratin.
Keratin is a protein present in many mammals, for example in humans keratin makes up nails and hair.
Keratin, in turn, is mainly composed of an amino acid: Cysteine

cysteine molecule

This amino acid, cysteine, contains a particular atom inside its chemical composition: sulphur.
Thanks to this particular atom, cysteine, and therefore keratin, can form links to different amino acids through disulphide bridges.
These particular links give the keratin macro structure a unique flaky fibre structure, which gives wool its thermal resistance and softness.
Thanks to this peculiarity of bridges between the sulphur atoms (that for example you don’t find in cotton molecules) wool is warm and soft.


on the left chemical reaction among cysteines to create disulphide bridges. Different disulphide bridges inside a keratin fibre

However, these molecules (cysteines) and links, disulphide bridges, are sensitive to alkaline pH and high temperatures.
These 2 factors can modify the keratin structure, by creating the well known felting problem.

>>> PROBLEM <<<

Felting is a process which modifies the link between the cysteines, by modifying the disulphide bridges causes a change in the wool fibre structure, a process with almost irreversible.
This process can be caused by:

• Excessive heat during drying
• Excessive mechanical action during wash
• Use of alkaline detergents

The excessive heat on dry fibre only, because meanwhile the fibre is still wet, the heat of the tumble dryer will eliminate only the water (making evaporate water from the fibres).
However once any humidity has been eliminated, the heat will act directly on fibre, irreversibly modifying the structure.
The felting process shortens fibres and re-arranges the molecules creating the well known problem - shrinkage.

shrinked jersey due to a wash and drying mistake

In some cases this can be intentionally induced, such as in worsted wool, because worsted wool has a smoother surface and poses less shrinkage problems, but on the other hand it loses some of its softness.
Another case, in the case it can be found in at the hairdressers, is the perm. Here the hair structure is intentionally modified by acting and modifying the cysteines link (the same molecules which constitute wool) throughout a chemical and heat treatment.

>>> SOLUTION <<<

In order to avoid and prevent this problem Dr. Conedera suggests:

Use right detergents with slightly acidic pH, such as Hygienfresh® WOOL & DELICATE (for use in normal washing machines) or HygienFresh® WOOL & SILK (for professional Wet Cleaning treatment).
Use wash programmes with a low mechanical action (low number of rotations and low spin speeds).
Wash with a low temperature (25°C max)
Avoid to excessively drying garments
Use conditioners and finishing agents which contain molecules that create a protective layer to avoid and prevent felting as well a providing nutrients to replenish the fibres, such as HygienFresh® SFELTRIX (for use in normal washing machines) or HygienFresh® Soft&Caps (for professional Wet Cleaning treatment).


is a highly concentrated detergent with lanolin, acid pH, buffer system and an intense and persistent Rose Milk fragrance.

Hygienfresh® Wool & Delicate detergent has been developed to softly clean and degrease wool fibres. Moreover it contains a particular complex to maintain a the correct pH in the wash bath. This particular system, called a buffer system, sets pH to a slightly acidic value and maintains it during the complete wash cycling. Moreover the buffer system, prevents possible operator error of accidentally dosing of alkaline products. Indeed, this system can neutralize alkaline detergents, ensuring that the pH remains at the correct value.
In addition, lanolin which is present in Hyienfresh® Wool & Delicate re-greases and replenishes the wool fibres during the wash cycle.

Method of use:
Add the detergent to the soap compartment the with machine fully loaded. It can also be used for hand washing too.

A39-510Dx12 – 12x1Lt
A39-510K – 10kg
A39-510N – 20kg

is the revolutionary silk protein based product which can nourish, replenish and protect wool, silk and delicate garments.

The innovative silk proteins, during the last rinse cycle, will lock onto the wool fibres, by covering them and creating a new structure. These special proteins create a new fibre layer, giving even softer “touch” to garment, by treating and regenerating the fibres, and above all, they will prevent problems of shrinkage. So in case of washing errors, fibres which have be damaged can be repaired with the silk proteins that can be found in Hygienfresh® Sfeltrix.


on the left: Images under the electronic microscope (SEM) of wool fibres: a) New wool fibre | b) Wool fibre after 20 washes with normal products | c) Wool fibre after 20 washes with Sfeltrix
on the right: Illustration of the chemical composition and structure of active silk proteins

Thanks to the silk proteins and their important and innovative process, Hygienfresh® Sfeltrix has also the ability of eliminate wool felting. Indeed, by reconstructing wool fibres, you can regain 1-2 lost sizes due to wool felting after a wash mistake.
Hygienfresh® Sfeltrix also contains lanolin the perfect finishing ingredient for woollen garments, so you can have, wash after wash, a nourished and regenerated fibre.

By using Hygienfresh® Sfeltrix along with Hygienfresh® Wool & Delicate detergent you can obtain excellent wash results for woollen garments, by obtaining clean, refreshed and nourished garments for an incomparable softness!

Method of use:
Add more over 10ml/Kg of product in the softener compartment during the last rinse, with a low water level.
You can use it also soak in order to regain lost sizes.
Put the garment soak with 50 ml of Hygienfresh® Sfeltrix in 5 litres of warm water, and move the garment every 15 minutes to stretch fibres.
After wash rig the garment to extend fibres. Then iron inside out with low temperatures.

A48-510Dx12 – 12x1Lt
A48-510K – 10kg
A48-510N – 20kg

In next newsletters we’ll speak about professional Wet Cleaning system and we’ll deepen our understanding of Hygienfresh® Wool& Silk and Hygienfresh® Soft & Caps products.

Read 522 times Last modified on Wednesday, 13 February 2019 09:55
More in this category: « A suitable detergent for each type of wash: WHITE GARMENTS Daily wash of white and coloured garments »

Do not miss the next appointment:


Subscribe to the newsletter and stay tuned on the latest news