Cyanine dyes and lithographic printing plate precursors comprising such dyes

1. A lithographic printing plate precursor comprising:

a cyanine dye including a first chromophoric group and a second chromophoric group that are different from each other; wherein

the first chromophoric group has a main absorption in the infrared region;

the second chromophoric group has a main absorption in the visible light region; and

the cyanine dye has a structure according to Formula I:

wherein

Z 1 represents S, CR 1a R 1b , or —CH═CH—;

Z 2 represents S, CR 2a R 2b , or —CH═CH—;

G represents H, CO 2 R or CONR′R″;

R, R′, and R″ independently represent H or an optionally substituted alkyl, aralkyl, or aryl group;

R 1a , R 1b , R 2a , R 2b , R 3a , R 3b , R 4a , and R 4b independently represent an optionally substituted alkyl, aralkyl, or aryl group, and R 1a and R 1b , R 2a and R 2b , R 3a and R 3b , R 4a and R 4b are capable of forming a ring;

R 1 , R 2 , R 3 , and R 4 independently represent an optionally substituted alkyl group;

R 5 , R 6 , R 7 , and R 8 independently represent hydrogen or an optionally substituted alkyl or aryl group, and R 5 and R 6 , R 7 and R 8 are capable of forming a ring;

R 9 represents hydrogen or an optionally substituted alkyl group;

T 1 , T 2 , T 3 , and T 4 independently represent H, F, Cl, Br, I, CF 3 , CN, an optionally substituted alkyl, alkoxy, or aryl group, an optionally substituted annulated benzo ring, —CO 2 R a1 , —CONR a2 R a3 , —SO 2 NR a4 R a5 , —SO 2 R a6 , or —SO 3 − , and R a1 , R a2 , R 3a , R a4 , and R a5 independently represent hydrogen or an optionally substituted alkyl or aryl group and R a6 represents an optionally substituted alkyl or aryl group;

m=0 or 2;

LINK represents a divalent linking group; and

counter ions are present to balance a charge of the cyanine dye.

2. The lithographic printing plate precursor according to claim 1 , wherein the cyanine dye has a structure according to Formula II:

3. The lithographic printing plate precursor according to claim 2 , wherein the cyanine dye has a structure according to Formula III:

wherein

n1, n2, n3, and n4 independently represent 1, 2, or 3.

4. The lithographic printing plate precursor according to claim 3 , wherein the cyanine dye has a structure according to Formula VI:

5. A negative working lithographic printing plate precursor comprising:

the cyanine dye as defined in claim 4 ; and

thermoplastic polymer particles.

6. A negative working lithographic printing plate precursor comprising:

the cyanine dye as defined in claim 3 ; and

thermoplastic polymer particles.

7. A lithographic printing plate precursor according to claim 2 , wherein the cyanine dye has a structure according to Formula V:

8. The lithographic printing plate precursor according to claim 2 , wherein the cyanine dye has a structure according to Formula VIII:

9. The lithographic printing plate precursor according to claim 8 , wherein the cyanine dye has a structure according to Formula X:

wherein n1, n2, n3, and n4 independently represent 1, 2, or 3.

10. The lithographic printing plate precursor according to claim 9 , wherein the cyanine dye has a structure according to Formula XII:

wherein

G represents H, CO 2 R or CONR′R″;

R, R′, and R″ independently represent H or an optionally substituted alkyl, aralkyl, or aryl group;

n represents 1, 2, or 3;

A is H or Br; and

counter ions are present to balance a charge of the cyanine dye.

11. A lithographic printing plate precursor comprising:

a cyanine dye including a first chromophoric group and a second chromophoric group that are different from each other; wherein

the first chromophoric group has a main absorption in the infrared region;

the second chromophoric group has a main absorption in the visible light region; and

the cyanine dye has a structure according to Formula IV:

wherein

G represents H, CO 2 R or CONR′R″;

R, R′, and R″ independently represent H or an optionally substituted alkyl, aralkyl, or aryl group;

R 1a , R 1b , R 2a , R 2b , R 3a , R 3b , R 4a , and R 4b independently represent an optionally substituted alkyl, aralkyl, or aryl group, and R 1a and R 1b , R 2a and R 2b , R 3a and R 3b , R 4a and R 4b are capable of forming a ring;

R 5 , R 6 , R 7 , and R 8 independently represent hydrogen or an optionally substituted alkyl or aryl group, and R 5 and R 6 , R 7 and R 8 are capable of forming a ring;

R 9 represents hydrogen or an optionally substituted alkyl group;

T 1 , T 2 , T 3 , and T 4 independently represent H, F, Cl, Br, I, CF 3 , CN, an optionally substituted alkyl, alkoxy, or aryl group, an optionally substituted annulated benzo ring, —CO 2 R a1 , —CONR a2 R a3 , —SO 2 NR a4 R a5 , —SO 2 R a6 , or —SO 3 − , and R a1 , R a2 , R a3 , R a4 and R a5 independently represent hydrogen or an optionally substituted alkyl or aryl group and R a6 represents an optionally substituted alkyl or aryl group;

m1, m2, m3, and m4 independently represent an integer ranging from 0 to 11;

m=0 or 2;

LINK represents a divalent linking group; and

counter ions are present to balance a charge of the cyanine dye.

12. The lithographic printing plate precursor according to claim 11 , wherein the cyanine dye has a structure according to Formula VII:

13. The lithographic printing plate precursor according to claim 12 , wherein the cyanine dye has a structure according to Formula XI:

14. A positive working lithographic printing plate precursor comprising:

the cyanine dye as defined in claim 12 .

15. A positive working lithographic printing plate precursor comprising:

the cyanine dye as defined in claim 11 .

16. A cyanine dye having a structure according to Formula I:

wherein

Z 1 represents S, CR 1a R 1b , or —CH═CH—;

Z 2 represents S, CR 2a R 2b , or —CH═CH—;

G represents H, CO 2 R or CONR′R″;

R, R′, and R″ independently represent H or an optionally substituted alkyl, aralkyl, or aryl group;

R 1a , R 1b , R 2a , R 2b , R 3a , R 3b , R 4a , and R 4b independently represent an optionally substituted alkyl, aralkyl, or aryl group, and R 1a and R 1b , R 2a and R 2b , R 3a and R 3b , R 4a and R 4b are capable of forming a ring;

R 1 , R 2 , R 3 , and R 4 independently represent an optionally substituted alkyl group;

R 5 , R 6 , R 7 , and R 8 independently represent hydrogen or an optionally substituted alkyl or aryl group, and R 5 and R 6 , R 7 and R 8 are capable of forming a ring;

R 9 represents hydrogen or an optionally substituted alkyl group;

T 1 , T 2 , T 3 , and T 4 independently represent H, F, Cl, Br, I, CF 3 , CN, an optionally substituted alkyl, alkoxy, or aryl group, an optionally substituted annulated benzo ring, —CO 2 R a1 , —CONR a2 R a3 , —SO 2 NR a4 R a5 , —SO 2 R a6 , or —SO 3 − , and R a1 , R a2 , R a3 , R a4 , and R a5 independently represent hydrogen or an optionally substituted alkyl or aryl group and R a6 represents an optionally substituted alkyl or aryl group;

m=0 or 2;

LINK represents a divalent linking group; and

counter ions are present to balance a charge of the cyanine dye.