Browning (or scorching) of a sublimation print out happens when the print out is too hot for too long and the paper will turn brown. This can result in blurred or incomplete image transfers.
While it might sound counter intuitive, turning the temperature of your heat press UP and reducing press time may help eliminate the issue.
JPPlus has a team of sublimation experts available to help with any questions you may have. Contact Customer Service at firstname.lastname@example.org or at 800-869-7800 Monday through Friday 8am to 8pm CST and they can put you in contact with someone who can help!