Phase change inks

• US 6,398,857 B1
• Filed: 08/03/2000
• Issued: 06/04/2002
• Est. Priority Date: 08/03/2000
• Status: Expired due to Term

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Wong, Raymond W., Breton, Marcel P., Malhotra, Shadi L.
• Primary Examiner(s): Klemanski, Helene
• Assistant Examiner(s): Faison, Veronica F.
• Application Number:
  US09/632,135
• Time in Patent Office: 670 Days
• Field of Search: 106/31.58, 106/31.86, 106/31.43, 106/31.75, 106/31.29, 106/31.61
• US Class Current: 106/31.29
• CPC Class Codes: C09D 11/34 Hot-melt inks

Abstract

Disclosed is an ink composition comprising (a) an ink vehicle comprising a benzoic acid compound substituted with an alkyl group, an alkoxy group, an arylalkyl group, an alkylaryl group, an arylalkyloxy group, or an alkyloxyaryl group; (b) a viscosity modifier; (c) a colorant; (d) an optional conductivity enhancing agent; (e) an optional antioxidant; and (f) an optional UV absorber.

Claims

1. An ink composition comprising (a) an ink vehicle comprising a benzoic acid compound substituted with an alkyl group, an alkoxy group, an arylalkyl group, an alkylaryl group, an arylalkyloxy group, or an alkyloxyaryl group;

(b) a viscosity modifier;

(c) a colorant;

(d) an optional conductivity enhancing agent;

(e) an optional antioxidant; and

(f) an optional UV absorber, said ink composition having a melting point of no lower than about 60°

C.

3. An ink composition according to claim 1 wherein the ink vehicle is present in the ink in an amount of at least about 20 percent by weight of the ink, and wherein the ink vehicle is present in the ink in an amount of no more than about 80 percent by weight of the ink.

4. An ink composition according to claim 1 wherein the viscosity modifier is a benzoic acid derivative, an acetic acid derivative, a propionic acid derivative, a butyric acid derivative, a hydroxy acid, a cyclic acid, a diacid, a fluorinated acid, an amino acid or amino acid derivative, or a mixture thereof.

6. An ink composition according to claim 1 wherein the viscosity modifier is present in the ink in an amount of at least about 5 percent by weight of the ink, and wherein the viscosity modifier is present in the ink. in an amount of no more than about 70 percent by weight of the ink.

7. An ink composition according to claim 1 wherein the colorant is a pigment.

8. An ink composition according to claim 1 wherein the colorant is a dye.

9. An ink composition according to claim 1 wherein the colorant is present in the ink in an amount of at least about 1 percent by weight of the ink, and wherein the colorant is present in the ink in an amount of no more than about 15 percent by weight of the ink.

12. An ink composition according to claim 1 wherein the ink has a haze value of no more than about 25.

13. An ink composition according to claim 1 wherein the ink has a hardness value of at least about 70 at temperatures of from about 20 to about 25°

C.

14. An ink composition according to claim 1 wherein the ink has a melting point of no lower than about 60°

C., and wherein the ink has a melting point of no higher than about 150°

C.

15. An ink composition according to claim 1 wherein at ink jetting temperatures the ink has a melt viscosity of no more than about 25 centipoise.

2. An ink composition comprising (a) an ink vehicle comprising a benzoic acid compound substituted with an alkyl group, an alkoxy group, an arylalkyl group, an alkylaryl group, an arylalkyloxy group, or an alkyloxyaryl group;

(b) a viscosity modifier;

(c) a colorant;

(d) an optional conductivity enhancing agent;

(e) an optional antioxidant; and

(f) an optional UV absorber, wherein the ink vehicle is 4-pentyl benzoic acid, 4-pentyloxy benzoic acid, 4-hexyl benzoic acid, 4-heptyl benzoic acid, 4-octyl benzoic acid, 4-octyloxy benzoic acid, 4-undecyloxy benzoic acid, 4-dodecyloxy benzoic acid, 4′

-(octyloxy)-4-biphenyl carboxylic acid, or mixtures thereof.

5. An ink composition comprising (a) an ink vehicle comprising a benzoic acid compound substituted with an alkyl group, an alkoxy group, an arylalkyl group, an alkylaryl group, an arylalkyloxy group, or an alkyloxyaryl group;

(b) a viscosity modifier;

(c) a colorant;

(d) an optional conductivity enhancing agent;

(e) an optional antioxidant; and

(f) an optional UV absorber, wherein the viscosity modifier is 2-acetylbenzoic acid, 3-methyl benzoic acid, 4-ethyl benzoic acid, 4-isopropyl benzoic acid, 2-hydroxy-3-isopropylbenzoic acid, 4-butyl benzoic acid, 2,4-dimethyl benzoic acid, 2,5-dimethyl benzoic acid, 2,6-dimethyl benzoic acid, 2-amino-6-methylbenzoic acid, 2,3-dimethoxybenzoic acid, 2,4-dimethoxy benzoic acid, 2,5-dimethoxy benzoic acid, 5-chloro-2-methoxybenzoic acid, 2-phenethyl benzoic acid, 2-phenoxy benzoic acid, 3,4,5-trimethoxy benzoic acid, 2,3,4-triethoxy benzoic acid, 2-hydroxy-3-isopropyl-6-methyl benzoic acid, 4-(bromo methyl)-3-nitrobenzoic acid, hydroxy acetic acid, 3-hydroxy phenylacetic acid, 3,4-dihydroxyphenyl acetic acid, (3,4-dimethoxyphenyl)acetic acid, (3,5-dimethoxy phenyl)acetic acid, (2,5-dimethoxy phenyl)acetic acid, 4-(dimethylamino) phenyl acetic acid, 4-benzyloxy-3-methoxyphenylacetic acid, 3,4,5-trimethoxyphenyl acetic acid, p-tolylacetic acid, o-tolylacetic acid, 2-acrylamidoglycolic acid monohydrate, thiodiglycolic acid, 3-(4-hydroxy phenyl) propionic acid, 3-(2-hydroxyphenyl) propionic acid, 3-(3,4-dimethoxy phenyl) propionic acid, 2-hydroxy-2-phenylpropionic acid hemihydrate, 3-(3,4,5-trimethoxyphenyl) propionic acid, 2-(p-tolyl) propionic acid, 3-bromo-2-(bromomethyl) propionic acid, 3-iodopropionic acid, 3,3′

-thiodipropionic acid, 3-(phenyl sulfonyl) propionic acid, 2-hydroxy-3-methylbutyric acid, 2-hydroxy-4-phenylbutyric acid, 2,2-bis(hydroxymethyl) butyric acid, 4,4′

-dithiobutyric acid, 4-(4-amino phenyl) butyric acid, 4-(2,4-di-tert-pentyl phenoxy) butyric acid, 4-benzoylbutyric acid, 2-(benxyloxy carbonylamino)-4-sulfamoyl butyric acid, 2-hydroxy isobutyric acid, 2-hydroxyisocaproic acid, 10-hydroxydecanoic acid, 12-hydroxy dodecanoic acid, 16-hydroxy hexadecanoic acid, 12-hydroxy stearic acid, 1-hydroxy-1-cyclopropane carboxylic acid, 2,2,3,3-tetramethylcyclopropane carboxylic acid, 1-benzo cyclobutane carboxylic acid, 3-oxo-1-indancarboxylic acid, 2-oxo-6-pentyl-2H-pyran-3-carboxylic acid, benzylmalonic acid, dibenzoyl tartaric acid monohydrate, methylsuccinic acid, 2-ethyl-2-methylsuccinic acid, 2,2-dimethylglutaric acid, 3,3-dimethylglutaric acid, 3-hydroxy-3-methyl glutaric acid, 3-oxadipic acid, 2-oxadipic acid, 5-oxazelaic acid, perfluorotetradecanoic acid, perfluorodecanoic acid, heptadecafluorononanoic acid, perfluoro adipic acid hydrate, N-acetyl cysteine, N-acetyl methionine, N-(acetoacetyl) glycine, N-(tert-butoxy carbonyl) alanine, N-(tert-butoxycarbonyl) phenylalanine, N-(tert-butoxycarbonyl) leucine monohydrate, N-(tert-butoxycarbonyl) aspartic acid, N-(tert-butoxycarbonyl) glutamine, N-(tert-butoxycarbonyl) serine, N-(tert-butoxy carbonyl) threonine, N-(tert-butoxy carbonyl) valine, carbobenzyloxy alanine, N-(carbobenzyloxy) phenylalanine, carbobenzyloxy glycine, N-(carbobenzyloxy) glutamic acid, carbobenzyloxy proline, carbobenzyloxy serine, N-(carbobenzyloxy) threonine, N-α

-(carbobenzyloxy) tryptophan, N,N-dipropyl alanine, N-(carbobenzyloxy) aspartic acid, N-(carbobenzyloxy)-α

-phosphono glycine trimethyl ester, N-(9-fluorenylmethoxy carbonyl) glutamic acid γ

tert-butylester monohydrate, N-(9-fluorenylmethoxy carbonyl) methionine, N-(9-fluorenylmethoxy carbonyl) proline, or mixtures thereof.

10. An ink composition comprising (a) an ink vehicle comprising a benzoic acid compound substituted with an alkyl group, an alkoxy group, an arylalkyl group, an alkylaryl group, an arylalkyloxy group, or an alkyloxyaryl group;

(b) a viscosity modifier;

(c) a colorant;

(d) an optional antioxidant;

(e) an optional UV absorber; and

(f) a conductivity enhancing agent which is perfluoro decyl iodide, 1,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8-heptadeca fluoro-10-iododecane, undecylenic acid zinc salt, methyl-1-adamantane sulfonate, octadecyl-4-chlorobenzene sulfonate, tetrabutylammonium trifluoromethanesulfonate, S,S′

-ethylene-p-toluene thiosulfonate, pyridinium-3-nitrobenzene sulfonate, or mixtures thereof.

11. An ink composition comprising (a) an ink vehicle comprising a benzoic acid compound substituted with an alkyl group, an alkoxy group, an arylalkyl group, an alkylaryl group, an arylalkyloxy group, or an alkyloxyaryl group;

(b) a viscosity modifier;

(c) a colorant;

(d) an optional antioxidant;

(e) an optional UV absorber; and

(f) a conductivity enhancing agent, wherein the conductivity enhancing agent is present in the ink in an amount of at least about 20 percent by weight of the ink, and wherein the conductivity enhancing agent is present in the ink in an amount of no more than about 35 percent by weight of the ink.

16. A process which comprises incorporating into an ink jet printing apparatus an ink composition comprising (a) an ink vehicle comprising a benzoic acid compound substituted with an alkyl group, an alkoxy group, an arylalkyl group, an alkylaryl group, an arylalkyloxy group, or an alkyloxyaryl group;

(b) a viscosity modifier;

(c) a colorant;

(d) an optional conductivity enhancing agent;

(e) an optional antioxidant; and

(f) an optional UV absorber, melting the ink, and causing droplets of the melted ink to be ejected in an imagewise pattern onto a print substrate.

17. A process according to claim 16 wherein the printing apparatus employs an acoustic ink jet process, wherein droplets of the ink are caused to be ejected in imagewise pattern by acoustic beams.

18. A process according to claim 16 wherein the printing apparatus employs an acoustic ink jet printing process wherein droplets of the ink are formed by acoustic beams without imparting a substantial velocity component toward the print substrate, using a droplet forming force that is sufficient only to form the ink droplets, and wherein the printing process further comprises generating an electric field to exert an electrical force different from the droplet forming force on the ink droplets to move the ink droplets toward the print substrate, and controlling the electrical force exerted on the formed complete ink droplets by the electric field.

19. A process according to claim 16 wherein the printing apparatus employs a piezoelectric ink jet process, wherein droplets of the ink are caused to be ejected in imagewise pattern by oscillations of piezoelectric vibrating elements.

20. A process according to claim 16 wherein the print substrate is heated during the printing process.