A tamper-evident adhesive security tape or label includes a flexible backing substrate with a surface that bears an embossed varnish layer, a semitransparent metal layer and/or a high refractive index layer, a partial release varnish layer, one or more varnish layers having optical properties, a full-area release varnish layer, a full-area varnish layer, and a self-adhesive coating layer. In regions not coated with the partial release varnish layer, an adhesion of the embossed varnish layer, the semitransparent metal layer and/or the HRI layer, the one or more varnish layers having optical properties, the full-area release varnish layer, the full-area varnish layer, the self-adhesive coating layer, and an article to be secured to one another is greater than an adhesion of the one or more varnish layers having optical properties to the full-area release varnish layer or an adhesion of the full-area release varnish layer to the full-area varnish layer.