Name: Luciana
Message: May Crayola Fabric crayons fix over time without any addition of heat? 
I want to add some details in my plush bears made of 100% polyester with crayola fabric crayons, but I am afraid the fibers may be damaged by iron.
Please help me!

No. That will not work. Like all disperse dyes, Crayola Fabric Crayons require very high heat, the temperature of a hot iron, to transfer into the fiber. Even a "warm" iron, which at 248°F is certainly hot enough to easily burn your skin should it touch you, is inadequate for dye transfer with disperse dye fabric crayons. Some synthetic fibers, such as modacrylic and polypropylene, will melt at the high temperatures required.

Instead, you should use fabric paint or fabric markers. Ordinary artists' acrylic paints will work for this if you do not mind their scratchy, harsh feeling after they dry. Dilute them a bit with water first. (Try them on a rag to see how they feel to you.) All Jacquard fabric paints, such as Lumiere, Neopaque, and Dye-na-flow, are claimed to work well on polyester. So will a number of other brands of fabric paint; try a test on a similar fabric or a less well-loved toy first. I am not sure how well fabric markers will work on 100% polyester, but at least they should be more suitable than disperse dye fabric crayons.

The heat required to heat-set fabric paints is lower than that required for disperse dyes. If you use Jacquard fabric paints, there is an additive called Jacquard Airfix which can be used as a substitute for heat-setting. Also, many fabric paints will slowly set at room temperature, and after a month or more of curing will be as permanent as if heat-set. Do not wash until after the heat-setting or an extended curing time is completed. Even after it is safe to wash items colored with fabric paints, be sure to hand-wash only, gently, because fabric paint can wear off of the surface of the fabric.

(Please help support this web site. Thank you.)