This is the best answer I could come up with. Good luck.
Q. How do I removed HeatnBond from fabric?
◦A. HeatnBond is a permanent adhesive. In order to remove HeatnBond from fabric, it can either be taken to a drycleaner that uses the chemical carbon tetrachloride (perc) which dissolves the adhesive in the fabric (please note that many states no longer use Perc in the dry cleaning process. It is best to call ahead and ask your dry cleaner.); or a product called Un-Du may be used in an attempt to remove the adhesive. Un-Du is a liquid adhesive remover which can usually be found in the scrapbooking section of major retailers such as Target or Michaels or at your local Scrapbook Store.
◦Simply squirt it on the area where the adhesive needs to be removed, and use the scraper to help eliminate it from the garment or fabric. The Un-Du will assist in dissolving the adhesive in the fabric. Finally, launder as normal.
◦Therm O Web can not guarantee any of the removal processes listed above. Results will vary depending on fabric, amount of adhesive to be removed and products and/or chemicals from other companies of which we have no control. Please test on an inconspicuous area before attempting removal.