A chelate and associated security feature including a lanthanide metal and a ligand of formula (1), formula (2), or formula (3), ##STR00001##
where each of R.sub.1-R.sub.7 in formula (1) is independently selected from the group consisting of H, OH, NH.sub.2, Cl, F, OMe, OAr, OCF.sub.3, CF.sub.3, alkyl, aryl, phenyl, OPh, and heteroaromatic, where each of R.sub.1-R.sub.5 in formula (2) is independently selected from the group consisting of H, OH, NH.sub.2, Cl, F, OMe, OAr, OCF.sub.3, CF.sub.3, NMe.sub.2, CN, alkyl, aryl, phenyl, OPh, and heteroaromatic, and where R.sub.6 in formula (2) is selected from the group consisting of H, NH.sub.2, Cl, F, OMe, OAr, OCF.sub.3, CF.sub.3, NMe.sub.2, CN, alkyl, aryl, phenyl, OPh, and heteroaromatic, and where each of R.sub.1-R.sub.5 in formula (3) is independently selected from the group consisting of H, OH, NH.sub.2, Cl, F, OMe, OAr, OCF.sub.3, CF.sub.3, alkyl, aryl, phenyl, OPh, and heteroaromatic.

A chelate and associated security feature including a lanthanide metal and a ligand of formula (1), formula (2), or formula (3), ##STR00001##
where each of R.sub.1-R.sub.7 in formula (1) is independently selected from the group consisting of H, OH, NH.sub.2, Cl, F, OMe, OAr, OCF.sub.3, CF.sub.3, alkyl, aryl, phenyl, OPh, and heteroaromatic, where each of R.sub.1-R.sub.5 in formula (2) is independently selected from the group consisting of H, OH, NH.sub.2, Cl, F, OMe, OAr, OCF.sub.3, CF.sub.3, NMe.sub.2, CN, alkyl, aryl, phenyl, OPh, and heteroaromatic, and where R.sub.6 in formula (2) is selected from the group consisting of H, NH.sub.2, Cl, F, OMe, OAr, OCF.sub.3, CF.sub.3, NMe.sub.2, CN, alkyl, aryl, phenyl, OPh, and heteroaromatic, and where each of R.sub.1-R.sub.5 in formula (3) is independently selected from the group consisting of H, OH, NH.sub.2, Cl, F, OMe, OAr, OCF.sub.3, CF.sub.3, alkyl, aryl, phenyl, OPh, and heteroaromatic.

A document which may be a security document has a thermochromic coating which may be a thermochromic ink on the substrate of the document. The ink may include several thermochromic materials which transition from various different colors to substantially clear in appearance as the ink is warmed to various temperatures. The combination of the colors of the thermochromic materials can give the document a different color at a number of different temperatures, until the coating is warmed to the highest color change point. When at or above the highest color change temperature, the coating becomes substantially transparent and the printed area assumes the color of the underlying substrate. The coating may also include non-reactive materials of yet another color that mixes with the colors of the thermochromic materials. The document may additionally include printed indicia on the substrate that are masked by the thermochromic materials at certain temperatures, and not masked by the thermochromic materials at other temperatures.

A document which may be a security document has a thermochromic coating which may be a thermochromic ink on the substrate of the document. The ink may include several thermochromic materials which transition from various different colors to substantially clear in appearance as the ink is warmed to various temperatures. The combination of the colors of the thermochromic materials can give the document a different color at a number of different temperatures, until the coating is warmed to the highest color change point. When at or above the highest color change temperature, the coating becomes substantially transparent and the printed area assumes the color of the underlying substrate. The coating may also include non-reactive materials of yet another color that mixes with the colors of the thermochromic materials. The document may additionally include printed indicia on the substrate that are masked by the thermochromic materials at certain temperatures, and not masked by the thermochromic materials at other temperatures.

A thermochromic ink composition includes, in a liquid medium, known as solvent, a dispersion of thermochromic microcapsules incorporating at least one leuco-dye and a thermoplastic binder selected from the group containing polyacrylic polyesters, polyurethanes and copolymers thereof. The composition is characterized in that the solvent is aprotic. A a method for producing a card and such a card incorporating at least one thermochromic pattern produced with a thermochromic ink composition are also described.

The present invention relates to the use of nanosystems as non deactivable security markers comprising metal atomic quantum clusters (AQCs) of at least two different size distributions encapsulated in a cavity with an inner diameter less than or equal to approximately 10 nm. These nanosystems are luminescence, particularly fluorescence after external excitation. The invention also relates to security documents, articles or elements incorporating these markers as well as to a method and a system for detecting the same.

The present invention relates to the use of nanosystems as non deactivable security markers comprising metal atomic quantum clusters (AQCs) of at least two different size distributions encapsulated in a cavity with an inner diameter less than or equal to approximately 10 nm. These nanosystems are luminescence, particularly fluorescence after external excitation. The invention also relates to security documents, articles or elements incorporating these markers as well as to a method and a system for detecting the same.

The present invention relates to microparticle compositions comprising an organic IR absorbing pigment having a main absorption maximum in the range from 750 to 1100 nm. The invention also relates to a process for producing said microparticle compositions and to their use in a printing ink, in particular in a printing ink, which is suitable for producing a security feature or a security document. The microparticles of the pigment composition contain the organic IR absorbing pigment as solid particles, which are surrounded by or embedded in an aminoplast polymer, which is a polycondensation product of one or more amino compounds and one or more aldehydes. The microparticle based pigment composition is characterized by a volume based particle size distribution, as determined by static light scattering according to ISO 13320:2009 EN, having a D(4,3) value in the range from 1.0 to 15.0 μm.

The present invention relates to microparticle compositions comprising an organic IR absorbing pigment having a main absorption maximum in the range from 750 to 1100 nm. The invention also relates to a process for producing said microparticle compositions and to their use in a printing ink, in particular in a printing ink, which is suitable for producing a security feature or a security document. The microparticles of the pigment composition contain the organic IR absorbing pigment as solid particles, which are surrounded by or embedded in an aminoplast polymer, which is a polycondensation product of one or more amino compounds and one or more aldehydes. The microparticle based pigment composition is characterized by a volume based particle size distribution, as determined by static light scattering according to ISO 13320:2009 EN, having a D(4,3) value in the range from 1.0 to 15.0 μm.

In order to increase the security of value or security documents 100, a multi-luminescent security element 400 is provided which contains at least one first luminescence means 510 and at least one second luminescence means 520. The first luminescence means 510 can be excited under first excitation conditions Sp-1 for the purpose of luminescence, and the second luminescence means 520 can be excited under second excitation conditions Sp-2 for the purpose of luminescence, said second excitation conditions Sp-2 differing from the first excitation conditions Sp-1. The multi-luminescent security element 400 is additionally equipped with at least one absorber means 600 which prevents an excitation of the at least one first luminescence means 510 under the second excitation conditions Sp-2 for the purpose of luminescence.