Q. How can I avoid having white lettering on a red polyester shirt turn pink?
Dye migration is a typical problem when it comes to decorating polyester. Generally, the darker or brighter the color, the more likely it is to occur. Dye migration is a result of the dyes in the fabric being activated when exposed to heat.
During the heat printing process these inks can bleed through your lettering, screen printing or transfer designs. You can test for dye migration by covering the garment with a kraft paper cover sheet and applying for 10 seconds with your heat press. Often, with unstable dyes, you will immediately see ink residue on the cover sheet.
If this occurs, make sure your white stays white and look for products that have dye blocking capabilities. Generally, this is spelled out in the product descriptions. Look for any of the following: high opacity, opaque, blocks dye migration, for darks, low bleed or bleed resistant and dye inhibiting.
Once you have chosen the material for you job, request a sample before purchasing the entire quantity. Dye migration does not always occur immediately. Apply your design and let it sit up to 24 hours. If the dye has not bleed through your design, you can be confident that the material you have selected will work for your job.
Even the best dye blocking heat transfer materials may not work on some fabrics. There is a wide range of polyester fabrics in the textile industry. The dye process differs from one manufacturer to the next. For this reason, I strongly encourage testing your heat application. Taking a few minutes to test before printing your entire job can save you time and money.
