preparing fabrics for dyeing and printing.

Preparing fabrics for dyeing and printing

Prior to dyeing or printing any natural or synthetic fabric, yarn or felt, it is important to ensure that it is fully prepared. There is an old dyers saying ‘well prepared is half dyed' which stresses the importance of preparation. Scouring is the name given to this process.

All fibres contain a combination of naturally occurring impurities and sizes, starches and oils which have been added during the spinning, weaving and knitting stages to bind the fibres together or to lubricate the yarns during processing

These natural and added processing aids, together with any general soiling, must be removed to ensure the fibre is clean and absorbent before commencing with printing or dyeing processes

You can check if a fabric has been scoured by allowing a droplet of water to fall onto the fabric surface. If it is quickly absorbed the there are not any water blocking agents present such as oils waxes and starches. If however the droplet remains on the surface then your fabric or yarn needs an efficient scouring.

Scouring

Remember to weigh you fabric before scouring, you will need to know the dry weight of your fabric later for calculating your dye recipe.

5Mls of METAPEX 38 Liquid (available in the dye kitchen and similar to a mild detergent like Woolite) in approx 2lts or water will be sufficient to scour 100grm of fabric, yarn or felt.

Using a large container or your CLEAN add hot water about 60 degrees. You will need thick heat protective gloves.

Add 5-10mls of Metapex and stir well before adding the fabric

Leave the fabric in the scouring liquor with occasional squeezing and stirring for 15-20 minutes

drain the scouring liquor and rinse in tepid water until the water is free from any foam

if the fabric is to be dyed immediately it need not be dried but if it is to be used for future use it should be dried, and ironed if it is to be used for printing