Security paper authentication system with dual instant color
View Patent ↗The present invention relates to a unique dual color security paper authentication system. The authenticating system comprises the combination of a security paper together with a coordinated applicator. The paper contains a starch, an iodide salt and an acidic developer resin. The applicator of the system comprises two authenticating solutions. The first authenticating solution comprises one or more of a sulfonamide and a copper salt dispersed in a solvent. The second authenticating solution comprises one or more of a leuco and fluoran dye precursor dispersed in a solvent. On applying the authenticating solutions to authentic security paper, a first color of a starch iodine is expressed and a second color of a leuco or fluoran dye is expressed.
1. A security paper authenticating system comprising the combination of a security paper and an applicator with at least two authenticating solutions, the security paper containing a starch, a salt of iodine, and an acidic developer material,
the applicator comprising a stylus with at least a dual element writing tip, wherein the first element of the writing tip communicates with a first chamber holding a first authenticating solution, and the second element of the writing tip communicates with a second chamber holding a second authenticating solution;
the first authenticating solution comprising one or more of a sulfonamide and a copper salt dispersed in a solvent;
the second authenticating solution comprising one or more of a leuco and fluoran dye precursor dispersed in a solvent;
whereby on applying the dual authenticating solutions to authentic security paper, iodine is generated in situ from the reaction of the first authenticating solution and salt of iodine, and a first color of a starch iodine color is expressed;
and whereby the second authenticating solution concurrently expresses a second color of a leuco or fluoran dye.
2. The system according to claim 1 wherein the salt of iodine is an alkali metal iodide.
3. The system according to claim 1 wherein the sulfonamide is of the formula
wherein R 1 is selected from C 1 -C 8 alkyl, hydroxyl, and carboxy;
wherein R 2 is selected from C 1 -C 8 alkyl, halogen, hydrogen, carboxy, carboxyaryl, and carboxyalkyl; and salts thereof.
4. The system according to claim 1 wherein the sulfonamide is an aryl sulfonamide.
5. The system according to claim 3 wherein the sulfonamide is n-chloro-p-toluene sulfonamide.
6. The system according to claim 1 wherein the copper salt is copper sulfate.
7. The system according to claim 1 wherein the paper contains a starch, iodide and an acidic developer material.
8. The system according to claim 7 wherein the acidic developer material is a phenolic resin.
9. The system according to claim 7 wherein the acidic developer material is selected from the group consisting of acetylated phenolic resin, salicylic acid modified phenoic resin, and novolac phenolic resin.
10. The system according to claim 1 wherein the acidic developer material is an inorganic acid mineral.
11. A security paper authenticating system comprising the combination of a security paper and an applicator with two authenticating solutions, the security paper containing a starch, a salt of iodine, and an acidic developer material,
the applicator comprising a stylus with a dual element writing tip, wherein the first element of the writing tip communicates with a first chamber holding a first authenticating solution, and the second element of the writing tip communicates with a second chamber holding a second authenticating solution;
the first authenticating solution comprising one or more of an aryl sulfonamide and copper sulphate dispersed in a solvent;
the second authenticating solution comprising one or more of a leuco and fluoran dye precursor dispersed in a solvent;
whereby on applying the dual authenticating solutions to authentic security paper, iodine is generated in situ from the reaction of the first authenticating solution and salt of iodine, and a first color of a starch iodine color is expressed;
and whereby the second authenticating solution expresses a second color of a leuco or fluoran dye.
12. The system according to claim 11 wherein the dual element writing tip is a combination of two writing tips each of which is separately retractable.
13. An authentication method comprising:
providing a substrate containing a starch, a salt of iodine, and an acidic developer material;
providing an applicator comprising two authenticating solutions maintained in separate chambers, wherein the first authenticating solution is selected from one or more of a sulfonamide and a copper salt, wherein the second authenticating solution comprises one or more of a leuco and fluoran dye precursor dispersed in a solvent;
applying the first authenticating solution to the substrate to express a first color of a starch iodine color;
and applying the second authenticating solution to the substrate to express a second color of a leuco or fluoran dye.
14. The method according to claim 13 wherein the first authenticating solution and the second authenticating solution are applied to the substrate concurrently.