| abstract |
A heat-sensitive recording material having an authentication feature, comprising a substrate, a thermosensitive recording layer containing a color former and color acceptors and an additional authentication feature-containing layer comprising non-colored water and / or alcohol-soluble solid particles, characterized in that the additional layer - in the form of a pattern, - in the form of logos and / or consecutive numbering, - and / or in forms, as they are known from watermarks, is applied, wherein the solid particles are strongly alkaline in an aqueous solution and form a substance which satisfies the following formula (1): |