According to http://support.brother.com/g/s/id/htmldoc/printer/cv_hll2300d/use/index.html#GUID-23D76C7B-650B-43C9-8AF2-B04B790F3A06_21, transparency film is not recommended for using in the laser printer. Also, the transparency film may fall into one of the categories of types of paper to avoid listed on http://support.brother.com/g/s/id/htmldoc/printer/cv_hll2300d/use/index.html#GUID-3501905E-9A00-4F4E-8BC3-07D9CA774DE2_22 .