Spotting delicate fabrics

A delicate fabric is described as a fabric that is capable of weakening and discoloring from mechanical action and the chemicals used for spotting. There are certain precautions that should be taken depending on the weaknesses of the particular fabric in question.

SILK

The problems with silk range from weak yarns and colors that is sensitive to certain chemicals.

• Mechanical action – Silks should be spotted with a padded silk brush or a bristled brush wrapped with a towel or cheesecloth. The safest mechanical action is tamping rather than brushing. When tamping, make sure that the fabric is flat to avoid damage. If brushing is attempted with a bristle brush use the side of the bristles rather than the flat brush.

• Protein stains – Silk is sensitive to alkali, ammonia and protein formulas which contain alkali. The safest chemical for protein stain removal is a powdered digester. This avoids the need for mechanical action and is as safe as water. Liquid digesters are relatively safe but not as safe as powdered digesters.

• Tannin stains – Tannin formulas and mild acids are relatively safe to silk. Stronger acids such as oxalic should be tested first. General formula which contains alcohol should never be used.

• Dryside stains – Strong paint remover should be avoided. The darker the color of the paint remover the stronger the agent is. Do not use water with any paint removers since the water causes alcohol to be released causing a discoloration. Dryclean garments immediately after spotting with paint remover to avoid moisture in the air which activates the alcohol in the paint remover. Amyl acetate is safe to all silk except those with a paint thinner.

Wool

Most wools are sturdy but have similar chemical sensitivity as silk does. Wools, however can withstand more mechanical action than silk. It also has a stronger resistance to using dryside paint removers. Water, with the paint removers should be avoided.

Acetate

Acetate fabrics should not be spotted with general formula which contains alcohol. As with silk, light colored or weaker paint removers should be used. After spotting with paint removers, the garment should be immediately drycleaned to avoid moisture in the air activating the alcohol in the paint remover. Tannin formulas and protein formulas are generally safe to acetate. Acetate does have a sensitivity to acetic acid even if it is in a diluted concentration.

Denims

Denims are subject to dye crocking and color loss from mechanical action. This means that you probably can not successfully remove any ink, dryside stains and paint stains without some color loss. Use tamping action as a safer form of mechanical action rather than brushing. It may be safer to spot from the back of the fabric when possible.

Satin weave

Satin weave contains floating yarns and is the weakest of all weaves. Always spot satin from the back of the fabric to avoid chafing of the yarns. Always use the silk brush for safer spotting.

Faille and ribbed fabrics

When spotting fabrics with a rib you should brush across the ribs rather then with the ribs. Brushing with the ribs will distort the delicate cross yarns.

Velvet

Acetate, silk and rayon velvet should not be spotted with water since distortion of the pile yarns can often occur. This distortion can usually not be corrected. Cotton and polyester velvet can be spotted but be careful to gently brush with the lay of the pile. This means that you should run your hands across the pile and find which way the pile feels smoother which indicates the lay of the pile.

SAFE BLEACHING

On colored fabrics, any bleach is capable of causing damage. On white fabrics some bleaches are safer than others.

• Wool and silk – Sodium bisulphate and sodium hydrosulphate are safest for bleaching and whitening wool and silk. Sodium hypochlorite can never be used. Hydrogen peroxide is the safest spot bleach that can be used.
• Cotton and linen – Sodium perborate and sodium percarbonate are the safest bath bleaches. Sodium hypochlorite is safe if diluted to a 1% concentration. Proper amount of the 1% concentration is required for safety. In spot bleaching, the 1% concentration should be heavily diluted before use. It is also necessary that after rinsing from bleaching acids be used to remove residual traces of the bleach.