System for interacting with analog-printed substrate

1. A system for interacting with a coded substrate, said system comprising:

a substrate having human-readable information and machine-readable coded data disposed thereon or therein; and

a sensing device for reading the machine-readable coded data,

wherein said coded data comprises an IR-absorbing phthalocyanine dye comprising one or more sulfonate groups, wherein a counterion of at least one sulfonate group is a phosphonium cation,

and wherein:

each phosphonium cation is of formula: P + (R m )(R n )(R s )(R t );

each of R m , R n , R s and R t is independently selected from the group consisting of: C 1-30 alkyl, C 5-12 aryl and C 5-30 arylalkyl; and

at least one of R m , R n , R s and R t comprises more than 4 carbon atoms.

2. The system of claim 1 , wherein said phthalocyanine dye is contained in a solvent-based or oil-based ink.

3. The system of claim 1 , wherein said substrate is printed by an analog printing process.

4. The system of claim 1 , wherein said substrate is a printed page.

5. The system of claim 1 , wherein said substrate is a label or packaging for a product item.

6. The system of claim 1 , wherein said phthalocyanine dye comprises a plurality of sulfonate groups.

7. The system of claim 6 , wherein said phthalocyanine dye comprising a corresponding plurality of phosphonium counterions.

8. The system of claim 1 , wherein said phthalocyanine dye is a naphthalocyanine dye.

9. The system of claim 1 , wherein said phthalocyanine dye is of formula (I):

wherein

M is Ga(A 1 );

A 1 is an axial ligand selected from the group consisting of: —OH, halogen, —OR 3 , —OC(O)R 4 and —O(CH 2 CH 2 O) e R e wherein e is an integer from 2 to 10 and R e is H, C l-8 alkyl or C(O)C 1-8 alkyl;

R 1 and R 2 may be the same or different and are selected from the group consisting of:

hydrogen and C 1-12 alkoxy;

R 3 is selected from the group consisting of: C 1-12 alkyl, C 5-12 aryl, C 5-12 arylalkyl and Si(R x )(R y )(R z );

R 4 is selected from the group consisting of: C 1-12 alkyl, C 5-12 aryl and C 5-12 arylalkyl;

R x , R y and R z may be the same or different and are selected from the group consisting of:

C 1-12 alkyl, C 5-12 aryl, C 5-12 arylalkyl, C 1-12 alkoxy, C 5-12 aryloxy and C 5-12 arylalkoxy; and

Z + is the phosphonium cation of formula: P+(R m )(R n )(R s )(R t ).

10. The system of claim 9 , wherein at least three of R m , R n , R s and R t comprise more than 4 carbon atoms.

11. The system of claim 9 , wherein at least three of R m , R n , R s and R t are independently selected from a C 6-30 alkyl group.

12. The system of claim 9 , wherein R 1 and R 2 are both hydrogen.

13. The system of claim 9 , wherein M is Ga(OH).

14. The system of claim 1 , wherein said sensing device comprises an image sensor with an IR filter.

15. The system of claim 14 , wherein said sensing device is an optically imaging pen.

16. The system of claim 15 , wherein said pen has a nib for interacting with the substrate.