Thermally sensitive, white light safe mask for use in flexography

摘要

The present invention provides a thermally imageable film having at least one thermally degradable binder, at least one infrared absorber, and additives. The thermally imageable film is transparent and remains transparent when exposed to white light wavelengths of about 390 to 750 nm or ultraviolet light wavelengths of about 190 to 390 nm. Upon imagewise exposure to infrared thermal radiation, the thermally imageable film forms an opaque area at the point of contact with the IR thermal radiation, the opaque areas of the film being ultraviolet light impermeable. The present invention also provides for a mask precursor or a relief printing plate precursor where the thermally imageable layer is coated directly onto a substrate as well as a method of making a mask or a relief printing plate using the thermally imageable film.