Latent security elements, i.e. detectable or becoming apparent only by use of special verification or tampering devices or methods

Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper impregnating or coating material, characterised by its function, form or properties > characterised by function or properties in or on the paper > Agents facilitating proof of genuineness or preventing fraudulent alteration, e.g. for security paper > Latent security elements, i.e. detectable or becoming apparent only by use of special verification or tampering devices or methods

Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties > characterised by function or properties in or on the paper (D21H19/66, D21H27/02 take precedence) > Agents facilitating proof of genuineness or preventing fraudulent alteration, e.g. for security paper (watermarking B41M3/10, D21F1/44; security printing B41M3/14; securities or banknotes characterised by colour effects B42D25/29, B42D25/30; testing paper currency or valuable papers for genuineness G07D7/00) > Latent security elements, i.e. detectable or becoming apparent only by use of special verification or tampering devices or methods