Ink formulations comprising gallium naphthalocyanines

• US 20080006177A1
• Filed: 07/10/2006
• Published: 01/10/2008
• Est. Priority Date: 07/10/2006
• Status: Active Grant

• Current Assignee: BASF SE
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Hall, Lachlan Everett, Silverbrook, Kia, Indusegaram, Sutharsiny, Vonwiller, Simone Charlotte, Starling, Scott Matthew, Ridley, Damon Donald, Gonzaga, Graciel
• Granted Patent: US 7,709,633 B2
• Time in Patent Office: Days
• US Class Current: 106/31.46
• CPC Class Codes: C09B 47/24 Obtaining compounds having —COOH or —SO3H radicals, or derivatives thereof, directly bound to the phthalocyanine radical
• CPC Class Codes: C09B 69/04 of anionic dyes with nitrogen containing compounds
• CPC Class Codes: C09D 11/328 characterised by dyes
• CPC Class Codes: G06K 19/06046 Constructional details

Abstract

There is provided an aqueous formulation comprising an IR-absorbing naphthalocyanine dye of formula (II):

or a salt form thereof, wherein:

• M is Ga(A¹);
• A¹ is an axial ligand selected from —OH, halogen, —OR³, —OC(O)R⁴ or —O(CH₂CH₂O)_eR^e wherein e is an integer from 2 to 10 and R^e is H, C_1-8 alkyl or C(O)C_1-8 alkyl;
• R¹ and R² may be the same or different and are selected from hydrogen or C_1-12 alkoxy;
• R³ is selected from C_1-12 alkyl, C_5-12 aryl, C_5-12 arylalkyl or Si(R^x)(R^y)(R^z);
• R⁴ is selected from C_1-12 alkyl, C_5-12 aryl or C_5-12 arylalkyl; and
• R^x, R^y and R^z may be the same or different and are selected from C_1-12 alkyl, C_5-12 aryl, C_5-12 arylalkyl, C_1-12 alkoxy, C_5-12 aryloxy or C_5-12 arylalkoxy;

The formulation has a pH in the range of 3.5 to 7 and is particularly suitable for use as an IR-absorbing inkjet ink, providing compatibility with known CMYK inks together with an optimally red-shifted λ_max.

Claims

1. An aqueous formulation comprising an IR-absorbing naphthalocyanine dye of formula (II):

2. The formulation of claim 1 having a pH in the range of 4 to 6.5.

3. The formulation of claim 1, wherein said formulation is buffered.

4. The formulation of claim 1 further comprising at least one base B, wherein a conjugate acid BH⁺ of said at least one base B has a pK_a of between 4 and 9.

5. The formulation of claim 4, wherein a conjugate acid BH⁺ of said at least one base B has a pK_a of between 4.5 and 8.

6. The formulation of claim 4 comprising a nitrogen base, an oxyanion base or mixtures thereof.

7. The formulation of claim 6, wherein said nitrogen base is a nitrogen-containing C_5-12 heteroaryl base.

8. The formulation of claim 7, said nitrogen base is imidazole or pyridine.

9. The formulation of claim 6, wherein said oxyanion base is a carboxylate base.

10. The formulation of claim 9, wherein said carboxylate base is of formula R⁵C(O)O—

, wherein R⁵ is selected from C_1-12 alkyl, C_5-12 aryl or C_5-12 arylalkyl.

11. The formulation of claim 4 comprising a nitrogen base and an oxyanion base.

12. The formulation of claim 1, wherein R¹ and R² are both H.

13. The formulation of claim 1, wherein M is Ga(OH).

14. An inkjet ink comprising a formulation according to claim 1.

15. An inkjet ink comprising a dye according to claim 1, wherein said ink has a λ

_max of 800 nm or more.

16. An inkjet printer comprising a printhead in fluid communication with at least one ink reservoir, wherein said at least one ink reservoir comprises an inkjet ink according to claim 14.

17. An ink cartridge for an inkjet printer, said ink cartridge comprising an inkjet ink according to claim 14.

18. A substrate having an ink according to claim 14 disposed thereon.

19. A method of enabling entry of data into a computer system via a printed form, the form containing human-readable information and machine-readable coded data, the coded data being indicative of an identity of the form and of a plurality of locations on the form, the method including the steps of:

receiving, in the computer system and from a sensing device, indicating data regarding the identity of the form and a position of the sensing device relative to the form, the sensing device, when placed in an operative position relative to the form, generating the indicating data using at least some of the coded data;

identifying, in the computer system and from the indicating data, at least one field of the form; and

interpreting, in the computer system, at least some of the indicating data as it relates to the at least one field,

wherein said coded data is printed using an ink according to claim 14.

20. A method of interacting with a product item, the product item having a printed surface containing human-readable information and machine-readable coded data, the coded data being indicative of an identity of the product item, the method including the steps of:

(a) receiving, in the computer system and from a sensing device, indicating data regarding the identity of the product item, the sensing device, when placed in an operative position relative to the product item, generating the indicating data using at least some of the coded data; and

(b) identifying, in the computer system and using the indicating data, an interaction relating to the product item,

wherein said coded data is printed using an ink according to claim 14.