National Clothesline

This month I’ll continue the discussion of using reducing bleaches for restoration which began in the September issue.

This is a very effective bleach for whitening fabrics and removing dye stains. It is acid in nature and accelerated by acids. It should not come into contact with metal.

Sodium hydrosulphite is also used as an antichlor for chlorine bleach or sodium hypochlorite.

It is used to counteract the effects of sodium hypochlorite. For example, if chlorine bleach discolored a wool or silk, the effects might be corrected by using sodium hydrosulphite.

Testing for restoration.To determine which bleach might be good for restoring whiteness or brightness to a fabric, it would be advisable to test on an unexposed area of the garment.

In my experience I have found that cotton, linen and rayons respond best to oxidizing bleaches such as perborate, percarbonate and a mild sodium hypochlorite.

White silks and wools might respond best to reducing bleaches such as sodium hydrosulphite.

1. Use a plastic open bucket for soaking garment.

2. Add warm water and mix in one to two ounces of sodium hydrosulphite per gallon of water.

3. Add a neutral lubricant to the mixture, which will reduce the odor of the hydrosulphite and give better penetration of the bleach and better rinsing.

4. Cover garment with a towel so the garment stays wet.

5. Soak for 15 minutes.

6. Rinse well.

Anticlor. Sodium hydrosulphite can be used as an anticlor. An anticlor works by completely neutralizing the residue of chlorine which might be left in a fabric.

1. Add sodium hydrosulphite in the ratio of one-half ounce per gallon of water. Also add a neutral lubricant in the ratio of one-half ounce per gallon of water.

2. After the anticlor, the garment must be given a final rinse.

Spot bleaching. Sodium hydrosulphite can be used as a spot bleach in two ways.

1. Use the sodium hydrosulphite powder directly on the stained area which has been previously dampened and then add a little neutral lubricant; heat with a steam gun; flush thoroughly.

2. Mix sodium hydrosulphite in a spotting bottle with enough water to dissolve the powder; add a little neutral lubricant; use a q-tip for removal of dye or correction of chlorine bleach contact.

Discoloration. Sodium hydrosulphite can sometimes leave a black discoloration on white fabrics after use. Use hydrogen peroxide for correction.

Residual odor. If sodium hydrosulphite leaves a lingering odor, use hydrogen peroxide, sodium perborate or percarbonate for correction.

Drogo. Wilson Chemical makes a product consisting of sodium hydrosulphite and a liquid fluorescent brightening agent.

Last resort procedure. There are sometimes situations where, after testing a bleach, you find it may have an adverse effect on the fabric but you have no alternative to using it. This can occur with dye stains that do not respond to normal or safe procedures.

For example, white acetate fabrics with dye stains may not respond to safe bleach or other procedures you might use.

Chlorine bleach or sodium hydrochlorite can usually remove dye stains on acetate but may leave a yellow discoloration. This yellow area has to be immediately neutralized using sodium hydrosulphite. It is a dangerous procedure to try, but as I said, it is only used as a last resort.

Another situation is trying to bleach a white area near a colored trimming or area. Use a q-tip very carefully to keep the bleach localized. Also, work fabric on a towel to keep bleach from spreading. It is also effective to use Vaseline near the trimmed area to protect migration of the bleach.