Always read and follow the care instructions and any warnings on the garment label. And, follow the General Rules for washable fabric stain removal.
Soak the entire garment in a dilute solution of all-fabric powered bleach. Check the garment care label and check for color fastness first. And, be aware that during soaking all colors may be lightened.
If the stain remains and the garment is colorfast, soak the entire garment in a dilute solution of liquid chlorine bleach and water. Again, test for colorfastness first.
Caution: Chlorine bleach may change the color of the garment or cause irreversible damage. Therefore, it is important to check for color fastness before using. If the stain does not come out within 15 minutes of bleaching, it cannot be removed by bleaching, and any further exposure to bleach will weaken the fabric.
Note: To check for color fastness to liquid chlorine bleach, mix 1 tablespoon of bleach with 1/4 cup of water. Use an eyedropper to put a drop of this solution on a hidden seam or pocket edge inside the garment. Let it stand two minute, then blot dry. If there is no color change it is safe to use the product. Powered bleaches have directions for doing colorfastness tests.
There are also a number of dye removers/strippers, such as one from Rit, which are available in drug and grocery stores. However, color removers will also take out fabric colors as well as the stain.
MEN'S HORIZONTAL DR. COOL SHIRT
This shirt is constructed using Coolcore's patented chemical-free moisture and sweat activated material to make sweat work for you. Rather than a simple wicking technology, the material delivers three distinct functions: wicking, moisture circulation, and regulated evaporation to reduce the fabric's surface temperature by up to 30%. Unlike other workout shirts Dr. Cool is chemical-free so that cooling benefits last the life of the shirt. Learn more about this technology. Shop for this technology>
KIDS SOLID COLOR SUNHAT
Made using a patented, chemical-free cooling fabric deigned by Coolcore, the Dr. Cool Kid's Sun Hat is the perfect sun protection. The wide brim provides shade while a moisture-wicking sweatband helps keep you cool. Colors: Blue, Fushia, Lime Punch. Learn more about this technology. Shop for this technology.