Why Some Patches Curl and How to Prevent It
https://s3.us-east-2.amazonaws.com/sewwhat-embroidered-patches-s3-2611/custom-patch-guides/uncategorized/how-to-brief-a-patch-maker-so-your-custom-patches-come-out-right.html
You sew or iron on a new patch, it looks great, and a few washes later the edges start lifting and the whole thing cups like a potato chip. Curling is one of the most common complaints about custom embroidered patches, and it is rarely random