Patent EA-004272-B1 (EA)
Title: Coating composition, preferably printing ink for security applications, method for producing a coating composition and use of glass ceramics
Inventor: EGGER PHILIPP
IPC: C09D5/22
Filed: 2000-12-02
Abstract: 1. Coating composition, preferably printing ink for security applications, comprising at least one organic resin, at least one pigment and optionally at least one organic solvent, characterized in that said pigment comprises glass ceramic composite particles which contain at least one crystalline phase embedded in glass matrix, said pigment having a particle size substantially comprised in the range of between 0.1 mum to 50 mum. 2. Coating composition according to claim 1 characterized in that the pigments have a particle size in the range of between 1pm to 20 pm, more preferably in a range of 3mum to 10 mum. 3. Coating composition according to claim 1 or 2 characterized in that the crystalline phase of the glass ceramic particle comprises a luminescent material. 4. Coating composition according to one of the claims 1 to 3 characterized in that the crystalline phase of said glass ceramic particle has a phonon energy not exceeding 580 cm<-1>, preferably not exceeding 400 cm<-1> and even more preferably not exceeding350 cm<-1>. 5. Coating composition according to one of the claims 1 to 4 characterized in that the glass ceramic particle is transparent to electromagnetic radiation in the range of between 400 to 750 mum. 6. Coating composition according to one of the claims 1 to 5 characterized in that the crystalline phase of said glass ceramic particle has average dimensions not exceeding 50 mum, preferably not exceeding 40 mum. 7. Coating composition according to one of the claims 1 to 6 characterised in that said crystalline phase of said glass ceramic particle contain at least one active ion for providing long wave to short wave light converting properties. 8. Coating composition according to one of the claims 1 to 7 characterised in that said crystalline phase of said glass ceramic composite contain at least one active ion for providing short wave to long wave light converting properties. 9. Coating composition according to claim 7 to 8 characterised in that said active ion is a rare-earth ion, preferably selected from the group of consisting of Pr<3+>, Nd<3+>, Sm<3+>, Eu<3+>, Tb<3+>, Dy<3+>, Ho<3+>, Er<3+>, Tm<3+> and Yb<3+>. 10. Coating composition according to one of the claims 1 to 9 characterized in that the glass ceramic particle is an oxyfluoride glass ceramics. 11. Coating composition according to 10 characterized in that the crystalline component of the glass ceramic particle comprises LaF3. 12. Coating composition according to one of the claims 10 or 11 characterized in that the glass matrix consisting essentially of Na2O<(>Al2O3<(>SiO2. 13. Security document characterized in that it comprises at least one layer produced by the coating composition, preferably a printing ink, according to one of the claims 1 to 12. 14. Use of at least one glass ceramic particle material having luminescent properties as a pigment. 15. Method of producing a coating composition, preferably printing ink, comprising glass ceramic particles as pigments comprising the steps of -providing glass ceramic pigment by comminuting said glass ceramic composite material to the required particle size, -incorporating said glass ceramic pigment into a coating composition or ink formulation, comprising at least one organic resin, at least one pigment and optionally at least one organic solvent.