Why does fabric need to be prewashed before you add paint to it?

Question

What will the outcome be if I skip the prewash?

Thx!

Answer 1

The shrinking issue is exactly correct.  However, if you are never going to wash and dry this item it is not nearly as important.

Answer 2

if you skip the prewash, your fabric might shrink.. then your paint can smear and distrack itself... prewash first...then paint... to make sure there is no shrinkage...

Answer 3

Because of shrinkage, and because of any chemicals or dirt that is on it.  Your paint may not set as well if there is a layer of something between it and the fabric.

Answer 4

Ideally, you want the paint to attach to the shirt fabric, not to the sizing. When the sizing washes out, the paint goes with it. Same thing applies if the shirt is pre-washed with fabric softener. Also, you want to use either fabric paint, or acrylic paint that's been mixed with textile medium. Dry and heat set according to label directions. I assume you know to stick a cardboard between the layers before you paint, too.

Sometimes you get lucky and it's ok, but mostly it's a sad disappearing act. If at all possible, prewash without fabric softener, but always use it once the fabric's painted. I did a t-shirt for a nephew this way many years ago, and it not only lasted fine for him, but for his younger brother too, and still looks good today.

Good luck!

Answer 5

In addition to the shrinkage issue, the manufactures use a sizing on the fabrics ( some more than others). The sizing should be removed to allow the best saturation of the paint. If it is not removed prior to painting, when washed the layer of sizing , a barrier between the fabric and the paint, will come off and the paint , or part of the paint with the sizing.

  The results are "iffy" after the first wash  if you do not prewash.

Answer 6

When fabric is made and wound on bolts at the printing mill, there are sprays/starches added to help control static and to make it lay better. Sometimes the layer of chemicals on the fabric is like a barrier that protects it; hence, paint cannot be absorbed unless it is washed first. There is also the concern for shrinkage of the fabric. Some fabrics can shrink up to an inch or more per yard depending on the quality of cotton used in them. Also, do not dry the fabric in the dryer with a dryer sheet as that can put a film on the fabric that could prevent dye/paint for adhereing to the fabric. Good luck with your project!!