Can You Discharge Bleach Clothes?
Though bleach is known for its powerful sanitation and whitening properties, it can also be damaging to fabrics. When used in excess, bleach and its fumes can degrade fabrics significantly and turn them yellow. For these reasons, bleach is generally not recommended for use in discharge clothes.
What Is Discharge Printing?
Discharge printing is a printing method that removes dye from a garment, typically to lighten a dark fabric or to produce a transparent print design. Instead of adding color to fabric, it removes the existing pigment from the garment, resulting in a ‘reverse color’ effect. The technique, which dates back to the mid 19th century, involves two steps: pre-discharge and post-discharge.
Does Discharge Printing Need Bleach?
In short, the answer is no. While bleach is sometimes used in fabric discharge printing, it is typically only in liquid form to remove color from areas of the garment prior to printing. Excess amounts of bleach can cause irreversible damages to fabrics and should be used with caution.
How Is Discharge Printing Done?
Discharge printing is typically done by first pre-treating the garment with a discharge paste with direct emulsion or a vat dye. This is done to change the pH of the dye, effectively turning it into this inert, non-absorbent substance. The pre-treatment lifts the dye from the fabric and leaves it open to absorb the new pigments.
To speed up the process, some companies use a dechlorination solution. This baths the fabric in chlorine to break down the dye and make the surface more receptive to the discharge printing.
What Are the Alternatives?
The majority of discharge printing does not require the use of bleach. Other methods can be used in its place.
- Dying: Pre-dying has become increasingly popular as a type of discharge printing. This is done by first dying the fabric and then bleaching the areas that need to be ‘discharged’. This removes the pigment from the fabric, allowing the new color to be printed in.
- Ultrasound: This method uses high-frequency sound waves to partially break down the bonds of the dye molecule and cause the color to fade. This is a great alternative to bleach because it doesn’t cause any damage to the fabric.
- Thermal Discharge: This is done by exposing the fabric to a series of heat and cold cycles which breaks down the dye and makes it easier to print over. This process is also free from damage to the fabric.
Bleach can be damaging to fabrics and should be used with caution. Most discharge printing processes do not need bleach and can be replaced with alternative methods such as dying, ultrasound and thermal discharge. Additionally, it’s important to always make sure to pre-test any product before using it on fabric to avoid potential damages.