National Clothesline

Remembering the four keys of can’t-fail bleaching described last month — concentration, acceleration, neutralizing and testing — we will continue with a discussion of sodium hypchlorite.

Sodium hypochlorite is a strong oxidizing agent which means it works by adding oxygen to a fabric or stain.

Sodium hypochlorite is household bleach and is one of the best cleaning and purifying agents available. It destroys more germs and bacteria as well as disinfects better than any agent readily available.

Commercial launderers doing hotel and hospital laundering will always use sodium hypochlorite. We all know that sodium hypochlorite is used effectively to purify the water in pools.

Sodium hypochlorite is also the best bleach to remove mildew, oxidize wetside staining and whitening many fabrics including cotton, linen and rayon.

Commercial mildew removers for cleaning tile in bathrooms are nothing more than sodium hypochlorite.

Sodium hypochlorite as well as other bleaches does not remove soil.

Sodium hypochlorite is readily available in the supermarket. The concentration that it comes in ranges from 5.25 percent to six percent.

You can buy a brand name of sodium hypochlorite such as Clorox or a store brand. It does not matter which one that you buy.

It is advisable to buy the smallest quantity available since the shelf life of sodium hypochlorite is limited. This means instead of buying a gallon of sodium hypochlorite, buy a 24-ounce or 1.5 pint bleach.

Sodium hypochlorite can also be obtained from suppliers at a higher concentration. This is completely unnecessary unless you are doing commercial laundering.

A small amount of bleach goes a long way since it should be diluted to a one percent concentration before use. Commercial launderers add sodium hypochlorite in a one percent concentration.

This means that if you are adding three-quarters of a cup of six percent sodium hypochlorite to the washer, it should first be diluted with water to a one percent concentration.

Three quarters of a cup of sodium hypochlorite is approximately six ounces, so you should first add 30 ounces or one quart of water to the six ounces. Then add one-half ounce of the one percent concentration per gallon of water.

For a stronger bleaching, we can use one ounce per gallon of water of a one percent concentration.

For spot bleaching, dilute one percent concentration to 50 parts water. This means that you might be adding ten drops of one percent sodium hypochlorite to a six-ounce bottle.

It is interesting to note that commercial launderers add less bleach than people doing wetcleaning. Commercial launderers add one percent of sodium hypochlorite based upon weight of clothes being laundered.

When doing bath bleaching or soaking, the water is first added and then the bleach is mixed in with a slight agitation.

Always add a neutral-based detergent in bath bleaching for a better penetration of the bleach.

Sodium hypochlorite is accelerated by heat and acids. Any acid such as acetic or oxalic will make the bleach stronger and act more quickly. The ability to accelerate the bleach is also used to remove last traces from a fabric.

The reaction of acids on sodium hypochlorite can be used in spot bleaching. For example, sodium hypochlorite followed by an acid accelerates it, making it stronger and more aggressive on the staining.

When doing bath bleaching, acid in the final rinse will accelerate last traces of sodium hypochlorite causing it to dissipate and be removed from the fabric.

Heat will also accelerate sodium hypochlorite. If I heat up sodium hypochlorite, I can double the chemical reaction with every 18 °F rise in temperature.

When soaking, use a 100°F water. Do not soak more than 15 minutes.

Longer soaking periods with sodium hypochlorite may not necessarily aid in stain removal but will start to affect the fabric.

There are chemicals that neutralize the effects of chlorine bleach.

This is important since chlorine bleach is not removed from fabrics in rinsing. It requires chemicals to stop the bleaching action.

Some of the chemicals that stop the bleaching action are known as anti-chlors. It must also be noted that chemicals used in conjunction with chlorine bleach can release toxic gases.

Sodium thiosulfate or hypo crystals neutralizes the effects of chlorine.

Hydrogen peroxide breaks down and neutralizes the effects of chlorine bleach. You never add it directly to the chlorine bleach since it reacts violently, producing oxygen gas. It is only used to remove the last traces of chlorine bleach after it has been rinsed.

Ammonia breaks down chlorine bleach releasing toxic gases. Ammonia is never used with chlorine bleach.

Reducing bleaches (Sodium hydrosulphite and sodium bisulphate) neutralize the effects of chlorine bleach effectively.

Reducing bleaches can also be used to reverse the discolorations caused by chlorine bleach. They work on the principle that chlorine bleach puts oxygen in a fabric and reducing bleach removes oxygen from a fabric.

All colors on fabrics should be tested before applying. Many colors are safe when using chlorine bleach in a one percent solution.

Wools and silks are generally unsafe.

Add warm water to a plastic pail and one-half ounce of one percent chlorine bleach per gallon of water.

Add a few ounces of a neutral detergent.

Place garment in pail and cover garment with a towel so it is submerged and not exposed to air.

Soak no more than 15 minutes.

Rinse in warm water.

Rinse again in water with any agent that can remove last traces of bleach. This can be peroxide, acid or reducing bleach.

Rinse again.

Spot bleaching

Mix 50 to one in spotting bottle of a one percent bleach concentration.

Use a q-tip to apply to a fabric.

Heat with steam gun.

Flush with steam.

Re-apply bleach.

Add acid.

Heat with steam gun.

Flush.

Add acid, reducing bleach or peroxide to remove last traces.

Flush.