Thermographic material useful for ticket, especially lottery ticket, has protective coating of water-insoluble, self-crosslinking acrylic polymer and crosslinker pigmented (mainly) with highly purified, alkali-treated bentonite

摘要

Thermographic material, has protective coating of water-insoluble, self-crosslinking acrylic polymer and crosslinker pigmented (mainly) with highly purified, alkali-treated bentonite. In thermographic sheet with a substrate, a thermographic layer containing a color coupler and acceptor and a protective coating containing binder (I), crosslinker (II) and pigment, this coating contains inorganic pigment(s) (III), including >= 80 wt.% highly purified alkali-treated bentonite (IIIA); (I) consists of water-insoluble, self-crosslinking acrylic polymer(s); the (I)/(III) ratio is 7:1 to 1:9; the (II).(I) ratio is over 1:5; and has a smoothness of >= 900 Bekk seconds.