Inks containing block copolymer micelles

• US 5,145,518 A
• Filed: 05/30/1991
• Issued: 09/08/1992
• Est. Priority Date: 06/27/1990
• Status: Expired due to Term

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Lin, John W-P., Winnik, Francoise M., Croucher, Melvin D., Davidson, Anthony R.
• Primary Examiner(s): Dixon, Jr., William R.
• Assistant Examiner(s): Einsmann, Margaret V.
• Application Number:
  US07/708,649
• Time in Patent Office: 467 Days
• Field of Search: 106/22, 8/647
• US Class Current: 523/161
• CPC Class Codes: C09D 11/30 Inkjet printing inks

Abstract

Disclosed is an ink composition which comprises an aqeuous liquid vehicle and particles of an average diameter of 100 nanometers or less which comprise micelles of block copolymers of the formula ABA, wherein A represents a hydrophilic segment and B represents a hydrophobic segment, and wherein dye molecules are covalently attached to the micelles, said dye molecules being detectable when exposed to radiation outside the visible wavelength range. Optionally, silica is precipitated within the micelles. In a specific embodiment, the dye molecules are substantially colorless. In another specific embodiment, the ink also contains a colorant detectable in the visible wavelength range.

Claims

1. An ink composition which comprises an aqueous liquid vehicle and particles of an average diameter of 100 nanometers or less which comprise micelles of block copolymers of the formula ABA, wherein A represents a hydrophilic segment and B represents a hydrophobic segment, and wherein dye molecules are convalently attached to the micelles, said dye molecules being detectable when exposed to radiation outside the visible wavelength range, wherein the A segments exhibit a solubility in water of at least about 0.2 gram per milliliter and the B segment exhibits a solubility in water of no more than about 0.01 gram per milliliter.

2. An ink composition according to claim 1 wherein the dye molecules are substantially colorless.

3. An ink composition according to claim 1 wherein the dye molecules are detectable when exposed to infrared radiation.

4. An ink composition according to claim 1 wherein the dye molecules are detectable when exposed to ultraviolet radiation.

5. An ink composition according to claim 1 wherein the ink also contains colored particles of an average diameter of 100 nanometers or less which comprise micelles of block copolymers of the formula ABA, wherein A represents a hydrophilic segment and B represents a hydrophobic segment, and wherein dye molecules are covalently attached to the micelles, said dye molecules being colored and detectable in the visible wavelength range.

6. An ink composition according to claim 5 wherein the colored dye detectable in the visible wavelenght range is selected from the group consisting of Reactive Dyes.

7. An ink composition according to claim 1 wherein the ink also contains colored particles of an average diameter of 100 nanometers or less which comprise micelles of block copolymers of the formula ABA having silica precipitated therein, wherein A represents a hydrophilic segment and B represents a hydrophobic segment, and wherein dye molecules are covalently attached to the micelles, said dye molecules being colored and detectable in the visible wavelength range.

8. An ink composition according to claim 1 wherein the ink also contains a colorant detectable in the visible wavelength range selected from the group consisting of pigments, dyes, and mixtures thereof.

9. An ink composition according to claim 1 wherein the liquid vehicle comprises a mixture of water and a water-miscible organic component.

10. An ink composition according to claim 9 wherein the water-miscible organic component is selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycols, glycerine, dipropylene glycols, polyethylene glycols, polypropylene glycols, amides, ethers, carboxylic acids, esters, alcohols, organosulfides, organosulfoxides, sulfones, alcohol derivatives, monoalkyl ethers of ethylene glycol, dialkyl ethers of ethylene glycol, monoalkyl ethers of diethylene glycol, dialkyl ethers of diethylene glycol, ether derivatives, amino alcohols, ketones, and mixtures thereof.

11. An ink composition according to claim 1 wherein the A segments of the block copolymers are of monomers selected from the group consisting of oxyethylenes, aminoethylenes, vinyl carboxylic acids and their corresponding esters of the general formula:

##STR13## wherein R₁ and R₂ are independently selected from hydrogen and alkyl groups with from 1 to about 20 carbon atoms, oxazolines of the general formula ##STR14## wherein R is hydrogen, an alkyl group with from 1 to about 6 carbon atoms, or benzyl and the ring has from about 2 to about 7 carbon atoms in addition to the carbon atom situated between the nitrogen and oxygen atoms, acrylamides of the general formula ##STR15## wherein R₁ is hydrogen, methyl, or ethyl, and R₂ and R₃ are independently selected from hydrogen, alkyl groups with from 1 to about 4 carbon atoms, hydroxyalkyl groups with from 1 to about 4 carbon atoms, and amino-substituted alkyl groups, vinyl ethers of the general formula ##STR16## wherein R₁ is selected from the group consisting of hydrogen, methyl, and ethyl, and R₂ is selected from hydroxy-substituted alkyl groups and amino-substituted alkyl groups, and mixtures thereof.

12. An ink composition according to claim 1 wherein the B segment of the block copolymers is of monomers selected from the group consisting of oxypropylenes, vinyl monomers, acrylic monomers and esters of monocarboxylic acids, olefins, and mixtures thereof.

13. An ink composition according to claim 1 wherein the block copolymers are selected from the group consisting of ABA block copolymers wherein the A blocks are polyethylene oxide and the B block is polypropylene oxide, ABA block copolymers wherein the A blocks are 2-hydroxyethyl vinylether polymers and the B block is a polymer of butyl vinyl ether, ABA block copolymers wherein the A blocks are polyethylene oxide and the B block is a polymer of 2-hydroxyethyl methacrylate, and mixtures thereof.

14. An ink composition according to claim 1 wherein the particles are present in the liquid vehicle in an amount of from about 0.5 to about 15 percent by weight.

15. An ink composition which comprises an aqueous liquid vehicle and particles of an average diameter of 100 nanometers or less which comprise micelles of block copolymers of the formula ABA having silica precipitated therein, wherein A represents a hydrophilic segment and B represents a hydrophobic segment, and dye molecules covalently attached to the micelles, said dye molecules being detectable when exposed to radiation outside the visible wavelength range, wherein the A segments exhibit a solubility in water of at least about 0.2 gram per milliliter and the B segment exhibits a solubility in water of no more than about 0.01 gram per milliliter.

16. An ink composition according to claim 15 wherein the dye molecules are substantially colorless.

17. An ink composition according to claim 15 wherein the dye molecules are detectable when exposed to infrared radiation.

18. An ink composition according to claim 15 wherein the dye molecules are detectable when exposed to ultraviolet radiation.

19. An ink composition according to claim 15 wherein the silica is contained in the micelles in an amount of from about 1.5 to about 39.5 percent by weight.

20. An ink composition according to claim 15 wherein the ink also contains colored particles of an average diameter of 100 nanometers or less which comprise micelles of block copolymers of the formula ABA, wherein A represents a hydrophilic segment and B represents a hydrophobic segment, and wherein dye molecules are covalently attached to the micelles, said dye molecules being colored and detectable in the visible wavelength range.

21. An ink composition according to claim 15 wherein the ink also contains colored particles of an average diameter of 100 nanometers or less which comprise micelles of block copolymers of the formula ABA having silica precipitated therein, wherein A represents a hydrophilic segment and B represents a hydrophobic segment, and wherein dye molecules are covalently attached to the micelles, said dye molecules being colored and detectable in the visible wavelength range.

22. An ink composition according to claim 15 wherein the ink also contains a colorant detectable in the visible wavelength range selected from the group consisting of pigments, dyes, and mixtures thereof.

23. In a printing process which comprises (1) incorporating into an ink jet printing apparatus an ink composition and (2) causing droplets of the ink to be ejected in an imagewise pattern onto a substrate, thereby generating images on the substrate, the improvement which comprises incorporating into the ink jet printing apparatus and jetting droplets onto the substrate an ink composition which comprises a liquid vehicle and particles of an average diameter of 100 nanometers or less which comprise micelles of block copolymers of the formula ABA, wherein A represents a hydrophilic segment and B represents a hydrophobic segment, and wherein dye molecules are covalently attached to the micelles, said dye molecules being detectable when exposed to radiation outside the visible wavelength range, wherein the A segments exhibit a solubility in water of at least about 0.2 gram per milliliter and the B segment exhibits a solubility in water of no more than about 0.01 gram per milliliter.

24. A printing process according to claim 23 wherein the dye molecules are substantially colorless.

25. A printing process according to claim 23 wherein the dye molecules are detectable when exposed to infrared radiation.

26. A printing process according to claim 23 wherein the dye molecules are detectable when exposed to ultraviolet radiation.

27. A printing process according to claim 23 wherein the micelles have silica precipitated therein.

28. A printing process according to claim 23 wherein the ink jet printing apparatus employs a thermal ink jet printing process.

29. A printing process according to claim 28 wherein the micelles have silica precipitated therein.

30. A printing process according to claim 23 wherein the ink also contains a colorant detectable in the visible wavelength range.

31. An ink composition which comprises an aqueous liquid vehicle and colored particles of an average diameter of 100 nanometers or less which comprise micelles of block copolymers of the formula ABA, wherein A represents a hydrophilic segment and B represents a hydrophobic segment, and wherein dye molecules are covalently attached to the micelles, wherein the A segments exhibit a solubility in water of at least about 0.2 gram per milliliter and the B segment exhibits a solubility in water of no more than about 0.01 gram per milliliter.

32. An ink composition according to claim 31 wherein the liquid vehicle comprises a mixture of water and a water-miscible organic component.

33. An ink composition according to claim 32 wherein the water-miscible organic component is selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycols, glycerine, dipropylene glycols, polyethylene glycols, polypropylene glycols, amides, ethers, carboxylic acids, esters, alcohols, organosulfides, organosulfoxides, sulfones, alcohol derivatives, monoalkyl ethers of ethylene glycol, dialkyl ethers of ethylene glycol, monoalkyl ethers of diethylene glycol, dialkyl ethers of diethylene glycol, ether derivatives, amino alcohols, ketones, and mixtures thereof.

34. An ink composition according to claim 31 wherein the A segments of the block copolymers are of monomers selected from the group consisting of oxyethylenes, aminoethylenes, vinyl carboxylic acids and their corresponding esters of the general formula:

##STR17## wherein R₁ and R₂ are independently selected from hydrogen and alkyl groups with from 1 to about 20 carbon atoms, oxazolines of the general formula ##STR18## wherein R is hydrogen, an alkyl group with from 1 to about 6 carbon atoms, or benzyl and the ring has from about 2 to about 7 carbon atoms in addition to the carbon atom situated between the nitrogen and oxygen atoms, acrylamides of the general formula ##STR19## wherein R₁ is hydrogen, methyl, or ethyl, and R₂ and R₃ are independently selected from hydrogen, alkyl groups with from 1 to about 4 carbon atoms, hydroxyalkyl groups with from 1 to about 4 carbon atoms, and aminosubstituted alkyl groups, vinyl ethers of the general formula ##STR20## wherein R₁ is selected from the group consisting of hydrogen, methyl, and ethyl, and R₂ is selected from hydroxy-substituted alkyl groups and amino-substituted alkyl groups, and mixtures thereof.

35. An ink composition according to claim 31 wherein the B segment of the block copolymers is of monomers selected from the group consisting of oxypropylenes, vinyl monomers, acrylic monomers and esters of monocarboxylic acids, olefins, and mixtures thereof.

36. An ink composition according to claim 31 wherein the block copolymers are selected from the group consisting of ABA block copolymers wherein the A blocks are polyethylene oxide and the B block is polypropylene oxide, ABA block copolymers wherein the A blocks are 2-hydroxyethyl vinylether polymers and the B block is a polymer of butyl vinyl ether, ABA block copolymers wherein the A blocks are polyethylene oxide and the B block is a polymer of 2-hydroxyethyl methacrylate, and mixtures thereof.

37. An ink composition according to claim 31 wherein the dye molecules are selected from the group consisting of Reactive Dyes.

38. An ink composition according to claim 31 wherein the colored particles are present in the liquid vehicle in an amount of from about 0.5 to about 15 percent by weight.

39. An ink composition which comprises an aqueous liquid vehicle and colored particles of an average diameter of 100 nanometers or less which comprise micelles of block copolymers of the formula ABA having silica precipitated therein, wherein A represents a hydrophilic segment and B represents a hydrophobic segment, and dye molecules covalently attached to the micelles, wherein the A segments exhibit a solubility in water of at least about 0.2 gram per milliliter and the B segment exhibits a solubility in water of no more than about 0.01 gram per milliliter.

40. An ink composition according to claim 39 wherein the silica is contained in the micelles in an amount of from about 1.5 to about 39.5 percent by weight.

41. In a printing process which comprises (1) incorporating into an ink jet printing apparatus an ink composition and (2) causing droplets of the ink to be ejected in an imagewise pattern onto a substrate, thereby generating images on the substrate, the improvement which comprises incorporating into the ink jet printing apparatus and jetting droplets onto the substrate an ink composition which comprises a liquid vehicle and colored particles of an average diameter of 100 nanometers or less which comprise micelles of block copolymers of the formula ABA, wherein A represents a hydrophilic segment and B represents a hydrophobic segment, and wherein dye molecules are covalently attached to the micelles, wherein the A segments exhibit a solubility in water of at least about 0.2 gram per milliliter and the B segment exhibits a solubility in water of no more than about 0.01 gram per milliliter.

42. A printing process according to claim 41 wherein the micelles have silica precipitated therein.

43. A printing process according to claim 41 wherein the ink jet printing apparatus employs a thermal ink jet printing process.

44. A printing process according to claim 43 wherein the micelles have silica precipitated therein.

45. An ink preparation process which comprises, in the order stated (1) adding to water a block copolymer of the formula ABA, wherein A represents a hydrophilic segment and B represents a hydrophobic segment, wherein the A segments exhibit a solubility in water of at least about 0.2 gram per milliliter and the B segment exhibits a solubility in water of no more than about 0.01 gram per milliliter, thereby forming a dispersion of micelles of the block copolymer;

(2) adding a water-soluble base to the dispersion, thereby bringing the pH of the dispersion to at least 8;

(3) adding to the dispersion a solution comprising water and a reactive dye capable of reacting with the block copolymer, thereby forming colored polymeric micelles; and

(4) admixing the colored micelles with an aqueous liquid vehicle to form an ink composition.

46. A process according to claim 45 wherein the A segments of the block copolymers are of monomers selected from the group consisting of oxyethylenes, aminoethylenes, vinyl carboxylic acids and their corresponding esters of the general formula:

##STR21## wherein R₁ and R₂ are independently selected from hydrogen and alkyl groups with from 1 to about 20 carbon atoms, oxazolines of the general formula ##STR22## wherein R is hydrogen, an alkyl group with from 1 to about 6 carbon atoms, or benzyl and the ring has from about 2 to about 7 carbon atoms in addition to the carbon atom situated between the nitrogen and oxygen atoms, acrylamides of the general formula ##STR23## wherein R₁ is hydrogen, methyl, or ethyl, and R₂ and R₃ are independently selected from hydrogen, alkyl groups with from 1 to about 4 carbon atoms, hydroxyalkyl groups with from 1 to about 4 carbon atoms, and amino-substituted alkyl groups, vinyl ethers of the general formula ##STR24## wherein R₁ is selected from the group consisting of hydrogen, methyl, and ethyl, and R₂ is selected from hydroxy-substituted alkyl groups and amino-substituted alkyl groups, and mixtures thereof.

47. A process according to claim 45 wherein the B segment of the block copolymers is of monomers selected from the group consisting of oxypropylenes, vinyl monomers, acrylic monomers and esters of monocarboxylic acids, olefins, and mixtures thereof.

48. A process according to claim 45 wherein the block copolymers are selected from the group consisting of ABA block copolymers wherein the A blocks are polyethylene oxide and the B block is polypropylene oxide, ABA block copolymers wherein the A blocks are 2-hydroxyethyl vinylether polymers and the B block is a polymer of butyl vinyl ether, ABA block copolymers wherein the A blocks are polyethylene oxide and the B block is a polymer of 2-hydroxyethyl methacrylate, and mixtures thereof.

49. A process according to claim 45 wherein the water soluble base is selected from the group consisting of ammonium hydroxide, sodium hydroxide, methyl amine, ethyl amine, propyl amine, and mixtures thereof.

50. A process according to claim 45 wherein the water soluble base is added to the dispersion in an amount of from about 5 to about 20 percent by weight of the dispersion.

51. A process according to claim 45 wherein the dye is added to the dispersion in an amount of from about 5 to about 30 percent by weight of the micelles.

52. A process according to claim 45 wherein the colored micelles are purified by filtration prior to admixing with the liquid vehicle.

53. An ink preparation process which comprises, in the order stated (1) adding to water a block copolymer of the formula ABA, wherein A represents a hydrophilic segment and B represents a hydrophobic segment, wherein the A segments exhibit a solubility in water of at least about 0.2 gram per milliliter and the B segment exhibits a solubility in water of no more than about 0.01 gram per milliliter, thereby forming a dispersion of micelles of the block copolymer;

(2) admixing a tetraalkoxysilane with the dispersion;

(3) adding a water-soluble base to the dispersion, thereby bringing the pH of the dispersion to at least 8, thereby precipitating silica within the micelles;

(4) adding to the dispersion a solution comprising water and a reactive dye capable of reacting with the block copolymer, thereby forming colored polymeric micelles with silica precipitated therein; and

(5) admixing the colored micelles with a liquid vehicle to form an ink composition.

54. A process according to claim 53 wherein alkoxy groups of the tetraalkoxysilane have from 1 to about 6 carbon atoms.

55. A process according to claim 53 wherein the tetraalkoxysilane is selected from the group consisting of tetraethoxysilane, tetramethoxysilane, tetra-n-propoxysilane, tetra-i-propoxysilane, tetra-n-butoxysilane, tetra-s-butoxysilane, tetra-i-butoxysilane, tetrapentoxysilane, tetrakis-(2-methoxyethoxysilane), and mixtures thereof.

56. A process according to claim 53 wherein the tetraalkoxysilane is added to the dispersion in an amount of from about 1 to about 30 percent by weight of the micelles.