Patent ID: 7126119

Claim:
Method for determining changes of a site, comprising: a) treating the site with a composition; and b) exposing the site thus treated and/or the untreated areas adjacent thereto to UV light; and determining the deviation b1) of the light intensity of the emitted light of a partial area of the site from the mean light intensity of the emitted light of the site area and/or b2) the light intensity of the emitted light of a part of the adjacent, untreated area from the mean light intensity of the emitted light of the adjacent untreated areas and/or b3) the light intensity of the emitted light of the site immediately after the treatment with the composition from the light intensity of the emitted light at a later time and/or b4) the light intensity of the emitted light of the adjacent untreated area immediately after the treatment of the site with the composition from the light intensity of the emitted light of the adjacent, untreated area at a later time wherein the composition is an aqueous dispersion comprising: a1) at least one binder a2) at least one substance emitting visible light on UV exposure and a3) optionally a dispersant, wherein the composition comprises a polyurethane as the binder of the componet a1) and said polyurethane is obtained by reaction with component i)–iv): i) diisocyanates containing 4 to 50 carbon atoms ii) diols having a molecular weight of 500 to 4 000 g/mol iii) diols as chain extenders having a molecular weight of 62 to 500 g/mol iv) mono- and polyols and/or mono- and polyamines having primary and/or secondary amino groups, which also have a group having a hydrophilizing effect.