Dan Eisen

The methods discussed here are intended for the advanced spotter who has knowledge of bleaching and mechanical action. It is dangerous for the novice who does not know proper testing or effects of chemicals on fabrics and dyes.

Spot bleaching is used for the chemical process of making last traces of wetside stains invisible or chemically changing the stain.

Bleaching facts

There are two types of bleaches which are oxidizing and reducing.

Oxidizing bleaches put oxygen into a fabric. Reducing bleaches remove oxygen from a fabric.

Oxidizing bleaches work primarily on last traces of tannin and protein. As a secondary action they also work on inks and dyes.

Reducing bleaches work primarily on dyes and inks. As a secondary action they are also effective on last traces of tannin and protein.

Oxidizing bleaches and reducing bleaches neutralize each other. This means if oxidizing bleach discolors a fabric it can sometimes be restored by using reducing bleach and vice versa.

Heat and chemicals accelerate bleaches.

The strength of a chemical is determined primarily by concentration.

Application of a lubricant with bleach provides better penetration and causes it to be more effective. Bleaches may not rinse out of a fabric and may require chemicals to neutralize the bleaches.

Test on fabrics and dyes before using.

Oxidizing bleaches

Hydrogen peroxide (H₂O₂).

Strength: 3% 10 volume; 30% 100 volume.

Use for ink, tannin, protein, dye.

For advanced spotting use 6% 20 volume. This is the concentration for hair bleach.

Use

1. Wet area.

2. Apply lubricant.

3. Apply peroxide and then ammonia (26).

4. Heat.

5. Flush.

6. Apply acetic acid.

7. Heat.

8. Flush.

Light Exposure Method

1. Apply lubricant.

2. Apply 6% peroxide.

3. Leave exposed to light.

4. Reapply every half hour.

5. Flush.

Sodium perborate and Sodium percarbonate

These bleaches are both obtained in powder form and they are alkaline by nature. They are both very effective oxidizing bleaches for spot bleaching. They are similar in nature although percarbonate is slightly stronger and faster acting. They both release hydrogen peroxide. They come in many products including all color safety bleaches for home use.

For proper spot bleaching, order the pure product from your jobber.

1. Wet area.

2. Apply lubricant.

3. Apply powder.

4. Heat.

5. Flush.

6. Apply powder plus ammonia.

7. Heat.

8. Flush.

9. Acetic acid.

10. Heat.

11. Flush.

Rapid reduction process

After applying either peroxide and ammonia or perborate or percarbonate do not flush the area.

Immediately apply acetic acid. Heat and then flush. This process produces a rapid reducing action and a chemical reaction called peroxyacid. Thorough flushing after using this process is necessary. Don’t forget to test.

Sodium Hypochlorite (or Chlorine Bleach Naocl)

A strong oxidizing bleach e.g. household bleach, Clorox.

Comes in 5.25%.

Alkaline by nature.

Cannot be used on animal fibers e.g. wool, silk, angora.

Cannot be used with alkali – causes it to decompose.

Used to remove tannin, dye, ink and mildew.

Procedure

Dilute 5.25% chlorine with 50% water.

Wet area.

Apply lubricant.

Apply bleach.

Heat.

Flush.

Acetic Acid.

Flush.

In order to obtain a stronger chemical action acetic acid can be added directly to the bleach before flushing.

Correction of yellowing produced high sodium hypochlorite can be accomplished by the following procedure.

Apply sodium hydrosulphite.

Heat.

Flush.

Potassium Permanganate

A strong oxidizing bleach that comes in purple crystals. Wilson Chemical sells a liquid permanganate for ink removal that is very effective.

Procedure

Wet area.

Apply lubricant.

Apply permanganate.

Heat.

Flush.

A brown discoloration is reduced by using either peroxide plus acetic or oxalic acid.

Flush thoroughly.

Reducing bleach

Sodium Bisulphite

Powder form.

Good for wine, berry, tannin stains.

Procedure

Wet area.

Apply lubricant.

Apply Bisulphite.

Heat.

Apply Acetic Acid.

Flush.

Sodium Hydrosulphite (reducing bleach)

This is a strong reducing bleach for dye stains.

Comes in powder form.

Procedure

Wet area.

Apply lubricant.

Apply powder.

Heat.

Apply acetic acid.

Heat.

Flush.

Titanium sulphate

Comes in a black liquid.

Sold in various trade names.

Use full strength.

Procedure

Place towel under fabric.

Wet area.

Apply stripper with Q-tip.

Heat.

Apply rust remover to area.

Heat.

Flush.

Protein formula to neutralize effects of rust remover.

Flush.

Any discolorations should be corrected by alternating the use of rust remover and (peroxide and ammonia). Remember to test fabric and flush thoroughly.

Dan Eisen recently retired as chief garment analyst for the Neighborhood Cleaners Association after 33 years with that organization. He is available for seminars, consultations and independent garment analysis. He also has published a book, “The Art of Spotting,” which is an indexed compilation of articles he wrote for National Clothesline and NCA over the past three decades. He can be reached at (561) 340-0909. His address is 274 NW Toscane Trail, Port St. Lucie, FL 34986. His e-mail address is cleandan@adelphia.net.