| 摘要 |
This invention relates to infrared transparency films and films for thermal imaging processes, and in particular, to a coating material for such films. Infrared imaging involves the use of a focused infrared lamp to heat an infrared absorbing image, i.e., the <<original>>, which is in contact with a substrate, e.g., a transparency film, having thermally sensitive imaging chemicals. Upon absorbing the focused infrared light, the infrared absorbing image heats the thermally sensitive imaging chemicals on the substrate, causing a chemical reaction, resulting in a copy of the original image on the substrate. When projection transparencies are prepared from originals which are plain paper copies prepared from electrophotographic imaging processes, localized heating of the original resuits in partial remelting of the toner powder thereon, causing the original to adhere to the transparency. When the original is separated from the transparency, toner powder from the original is transferred to the transparency film, resulting in partial destruction of the original and irregular black spots on the transparency. This invention provides thermally imageable film comprising a polymeric substrate, a layer of thermally imageable material coated over at least one major surface thereof, and a release coating coated over the layer of thermally imageable material. The release coating is an organopolysiloxane applied from a composition which is curable at temperatures below about 70 DEG C with a curing exposure time of under about 3 minutes, thereby preventing adverse effects upon the layer of thermally imageable material. The release coating serves to prevent the transfer of toner powder from an original to the transparency film. |
