White fabrics produced in manufacture will usually have a gray or yellowish tint. To offset the discolored look fabrics are bleached in manufacture to create a white fabric. Fluorescent dyes or optical brightness are then added to the fabric to increase the whiteness of the fabric. Fluorescent dyes increase the brightness by converting invisible ultra-violet light to visible light. Although fluorescent dyes are often added to colored fabrics the problems that drycleaners encounter are usually confined to white fabrics.
FABRICS CAUSING FLUORESCENT DYE BREAKDOWN
A fluorescent dye breakdown can occur from many factors. This includes sunlight, drycleaning solvents, staining substances and chemicals used for stain removal. Strong bleaches and strong chemicals will also break down the fluorescent dye on most fabrics.
DETECTION OF FLUORESCENT DYES
When observed under black light a fluorescent dye will glow. When the fluorescent dye is removed the area will not show any degree of fluorescence. Many drycleaners are using the portable Spectralight which I invented to be used to examine fabrics for staining and for fluorescent dye.
It is important when correcting a fluorescent dye breakdown that the fabric is taken into consideration. Different fabrics require different procedures for restoration. Correction of fluorescent dye problems is accomplished by wetcleaning and bleaching but not in drycleaing.
REMOVE STAINING SUBSTANCES
You cannot correct a fluorescent dye if staining substances or residue is still left in the fabric. If you have a tannin or protein stain the staining substance must be removed first. If the fabric is gray with redeposition of soil the fabric cannot be made lighter unless the redeposition of soil is corrected. Fluorescent dyes cannot camouflage staining.
CORRECTING FLUORESCENT DYES ON SILKS AND WOOLS
The fluorescent dyes on silks and wools are affected by alkalis found in protein formulas and ammonia. It is important to avoid using these chemicals for stain removal. To correct a fluorescent dye breakdown alkaline based bleaches such as sodium perborate and sodium percarbonate should be avoided. The best bleaches to use for correction are acid based agents. This includes sodium bisulphate and sodium hydrosulphate.
- Soak garment in a plastic pail with 1-2 ounces of bleach per gallon of water.
- Add a few ounces of a mild detergent for better penetration when soaking.
- Soak garment for approximately 10-15 minutes.
- Rinse garment thoroughly and add a little detergent to the rinse water. A small amount of detergent in the rinse water will aid in increasing the brightness of the fabric.
Wilson Chemical makes a product called Dro-go which is also effective for these types of problems.
CORRECTING FLUORESCENT DYES ON COTTONS, RAYONS AND LINENS
These fabrics require an alkaline based bleach. These bleaches include sodium perborate and sodium percarbonate.
- Soak garment in a plastic pail with warm water adding one to two ounces of bleach per gallon.
- Add a mild detergent to the bleach bath.
- Soak garment overnight and rinse thoroughly.
- Use a mild acid to neutralize the bleaching action.
- Rinse again and add a mild detergent to increase the brightness.
Bluing can be an important asset for whitening a white fabric. The brightest white fabrics have a slight blue hue. When manufacturers bleach fabrics they add fluorescent dyes and a slight blue color. Bluing has the ability to mask a yellow tint and gives the fabric an additional whiteness. A popular bluing agent that is very effective can be obtained in most supermarkets under the name Mrs. Stuarts Liquid Bluing.
Those drycleaners who are interested in purchasing my Spectralight (portable or mini) which can even be carried in your pocket should contact me either by phone at 772-340-0909 or email me at: email@example.com . I have been providing restoration services to several drycleaners and have been very successful with helping them in the restoration processes. If you have a garment that may need restoration please contact me and we will discuss it.