Waterfast ink composition for printers

• US 5,674,314 A
• Filed: 12/11/1995
• Issued: 10/07/1997
• Est. Priority Date: 12/11/1995
• Status: Expired due to Term

• Current Assignee: Pitney Bowes Incorporated (Böwe Systec AG)
• Original Assignee: Pitney Bowes Incorporated (Böwe Systec AG)
• Inventors: Auslander, Judith D., Higashiyama, Shunichi
• Primary Examiner(s): KLEMANSKI, HELENE G
• Application Number:
  US08/570,224
• Time in Patent Office: 666 Days
• Field of Search: 106/21 A, 106/22 R, 106/22 B
• US Class Current: 524/104
• CPC Class Codes: C09D 11/30 Inkjet printing inks

Abstract

Liquid inks are disclosed that fulfill United States Postal Service requirements for automation compatibility, while being able to be used in an ink jet printer. The inks of this invention may be read by current United States Postal Service equipment. The inks are waterfast, having improved print quality. The formulations are based on water cosolvent solutions of soluble fluorescent or non fluorescent toners to which toning dyes and non ionic surfactants are added.

Claims

1. A postage metering system having a printing mechanism for printing postage, the improvement comprising:

within the printing mechanism employing an aqueous water-fast ink containing water, water soluble organic solvents, soluble toners and a glycol ether that are inert to any plastic material contained in the printing mechanism.

2. The system of claim 1, wherein the waterfast ink composition consists essentially of:

a. 35-55 (Wt. %) water;

b. 15-50 (Wt. %) water soluble organic solvents having a hydrogen bonding solubility parameter (δ

_h) greater than 8.0, a polar solubility parameter (δ

_p) greater than 5.0 and a dispersion parameter (δ

.sub.δ

) between 7-8.3;

c. 3-15 (Wt. %) soluble toners with a molecular weight less than 6,000;

d. trace-8.0 (Wt. %) direct, acid, basic or reactive water soluble toning dye; and

e. 5-15 (Wt. %) of cosolvent penetrant.

3. The system of claim 1, wherein the waterfast ink composition consists essentially of:

a. 35-55 (Wt. %) water;

b. 15-47 (Wt. %) water soluble organic solvents having a hydrogen bonding solubility parameter (δ

_h) greater than 5.0, a polar solubility parameter (δ

_p) between 8.0-8.7 and a dispersion parameter (δ

.sub.δ

) between 8.4-10.0;

c. 3-15 (Wt. %) soluble toners with a molecular weight between 200 and a 1,000;

d. trace-8.0 (Wt. %) direct, acid, basic or reactive water soluble toning dye; and

e. 5-15 (Wt. %) of cosolvent penetrant.

4. The system of claim 1, wherein the waterfast ink composition consists essentially of:

a. 35-55 (Wt. %) water;

b. 5-25 (Wt. %) water soluble organic solvents having a hydrogen bonding solubility parameter (δ

_h) greater than 8.0, a polar solubility parameter (δ

_p) greater than 5.0 and a dispersion parameter (δ

.sub.δ

) between 7-8.3;

c. 5-25 (Wt. %) water soluble organic solvents having a hydrogen bonding solubility parameter (δ

_h) greater than 5.0, a polar solubility parameter (δ

_p) between 8.0-8.7 and a dispersion parameter (δ

.sub.δ

) between 8.4-10.0;

d. 3-15 (Wt. %) soluble toners with a molecular weight between 200 and a 1,000;

e. trace-8.0 (Wt. %) direct, acid, basic or reactive water soluble toning dye; and

f. 5-15 (Wt. %) of cosolvent penetrant.

13. The composition of claim 1, wherein the glycol ethers have a viscosity of less than 20 cps.

15. The composition of claim 1, wherein the polyester polyamide soluble toner has an acid number greater than 50.

5. A aqueous water fast ink composition consisting essentially of:

a. 35-55 (Wt. %) water;

b. 15-50 (Wt. %) water soluble organic cosolvents having a hydrogen bonding solubility parameter (δ

_h) greater than 8.0, a polar solubility parameter (δ

_p) greater than 5.0 and a dispersion parameter (δ

.sub.δ

) between 7-8.3;

c. 3-15 (Wt. %) soluble toners with a molecular weight less than 6,000;

d. trace-8.0 (Wt. %) direct, acid, basic or reactive water soluble toning dye; and

e. 5-15 (Wt. %) of glycol ether as a cosolvent penetrant.

6. The composition claimed in claim 5, wherein the soluble toners have a weight average molecular weight between 300 and 700.

7. The composition claimed in claim 6, wherein the, soluble toners contain non ionic surfactants to increase the solubility of the ink.

8. The composition claimed in claim 7, wherein the non ionic surfactant has an HLB between 8 and 15.

9. The composition claimed in claim 8, wherein the non ionic surfactant is selected from the group consisting of:

tridecyl alcohol ethoxylates and nonyl phenoxy poly (ethyleneoxy) ethoxylates.

10. The composition claimed in claim 5, wherein the soluble toners are fluorescent toners.

11. The composition of claim 5, wherein the toning dye is selected from the group consisting of C.I. Direct Yellow 86, C.I. Acid Yellow 210, C.I. Basic Yellow, 40, C.I. Basic Yellow 51, C.I. Basic Yellow 2.

12. The composition claimed in claim 5, wherein the soluble toners are clear toners.

14. The composition of claim 5, wherein the soluble toner is selected from the group consisting of urea formaldehyde toluene sulfonamide, polyester-polyamide or dimethyl hydantoin formaldehyde.

16. The composition of claim 5, wherein the water soluble organic solvents individually or in solution do not exceed a viscosity of 20 cps.

17. The composition of claim 16, wherein the water soluble organic solvents have a vapor pressure less than 0.1 mm/Hg at room temperature.

18. The composition claimed in claim 5, wherein the water soluble organic solvents are selected from the group consisting of:

pyrrolidone, N-methyl pyrrolidone or triethylene glycol.

19. The composition of claim 7, wherein the toning dye is selected from the group consisting of:

Basic Yellow 40, Basic Yellow 51, Basic Blue 7, Basic Blue 3 and C.I. Direct Yellow 142.

29. The composition of claim 16, wherein the toning dye is selected from the group consisting of:

Basic Yellow 40, Basic Yellow 51, Basic Blue 7, Basic Blue 3 and C.I. Direct Yellow 142.

20. A aqueous water fast ink composition consisting essentially

a. 35-55 (Wt. %) water;

b. 15-47 (Wt. %) water soluble organic solvents having a hydrogen bonding solubility parameter (δ

_h) greater than 5.0, a polar solubility parameter (δ

_p) between 8.0-8.7 and a dispersion parameter (δ

.sub.δ

) between 8.4-10.0;

c. 3-15 (Wt. %) soluble toners with a molecular weight between 200 and a 1,000;

d. trace-8.0 (Wt. %) direct, acid, basic or reactive water soluble toning dye; and

e. 5-15 (Wt. %) of glycol ether as a cosolvent penetrant.

21. The composition claimed in claim 20, wherein the soluble toners contain non ionic surfactants to increase the solubility of the ink.

22. The composition claimed in claim 21, wherein the non ionic surfactant has an HLB between 8 and 15.

23. The composition claimed in claim 22, wherein the non ionic surfactant is selected from the group consisting of:

tridecyl alcohol alkoxylates and nonyl phenoxy polyoxy ethylene alcohols.

24. The composition claimed in claim 23, wherein the non ionic surfactant is used at concentrations from trace to 3 Wt. %.

25. The composition claimed in claim 20, wherein the soluble toners are fluorescent toners.

26. The composition claimed in claim 20, wherein the soluble toners are clear toners.

27. The composition of claim 25, wherein the fluorescent toner is selected from the group consisting of urea formaldehyde toluene sulfonamide, polyester polyamide or dimethyl hydantoin formaldehyde.

28. The composition of claim 20, wherein the water soluble organic solvents are selected from the group consisting of 2-Pyrrolidone, N-methyl pyrrolidone, sulfolane, and gamma butyrlactone.

30. A aqueous water fast ink composition consisting essentially of:

a. 35-55 (Wt. %) water;

b. 5-25 (Wt. %) water soluble organic solvents having a hydrogen bonding solubility parameter (δ

_h) greater than 8.0, a polar solubility parameter (δ

_p) greater than 5.0 and a dispersion parameter (δ

.sub.δ

) between 7-8.3;

c. 5-25 (Wt. %) water soluble organic solvents having a hydrogen bonding solubility parameter (δ

_h) greater than 5.0, a polar solubility parameter (δ

_p) between 8.0-8.7 and a dispersion parameter (δ

.sub.δ

) between 8.4-10.0;

d. 3-15 (Wt. %) soluble toners with a molecular weight between 200 and a 1,000;

e. trace-8.0 (Wt. %) direct, acid, basic or reactive water soluble toning dye; and

f. 5-15 (Wt. %) of glycol ether as a cosolvent penetrant.