| CPC B29C 51/445 (2013.01) [B29C 33/68 (2013.01); B29C 51/002 (2013.01); B29C 51/14 (2013.01); B29C 51/32 (2013.01); B29C 51/428 (2013.01); B29C 2793/009 (2013.01)] | 20 Claims |

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1. A detached releasable separator film, for use with a thermoformable sheet material in forming a thermoformed dental appliance, the detached releasable separator film comprising a polypropylene co-polymer or a polyolefin having (i) an average thickness of from about 37 to 75 microns; (ii) a melting point of from about 60° C. to about 200° C.; (iii) a trouser tear strength of greater than 20 N/mm; and (iv) a modulus of from about 50 MPa to about 700 MPa.
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