Our Jollysox socks made of mercerised cotton (also known as Scottish yarn) guarantee a colour that remains brilliant and original, despite frequent washing.

Mercerisation stands for the application of cold caustic soda on the taut cotton. This method smooths the surface of the fibres to increase the brightness and colour. This colourful brilliance is permanently resistant to washing, boiling and cleaning. The mercerised cotton is also known as pearl cotton.

Our original Jollysox socks in mercerised cotton also have a toe and heel reinforcement to ensure better resistance to wear and tear.

The mercerisation process (or mercerising) expands the cotton fibre. The term "Scottish yarn" is also used for "long fibred" cotton yarn which has been assembled by twisting following double mercerisation.

Scottish Yarn :
The Scottish yarn is a type of cotton that has been treated with gas and mercerisation, which gives it a look that is both smooth and shiny and makes it more flexible as well as giving it unequalled comfort.
Jollysox socks made of Scottish yarn are prized for their appearance, strength and incomparable softness.
Scottish thread is of a higher quality and is only used for the manufacture of socks and knee-highs.

This means that mercerised cotton is brighter and retains its colour even after frequent washing.

Jollysox carefully selects its manufacturers based on multiple criteria (types of machine, choice of yarn suppliers and rigorous deadlines).