Preparation of improved inks for inkjet printers

• US 20020156156A1
• Filed: 04/25/2002
• Published: 10/24/2002
• Est. Priority Date: 04/21/1999
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Gore, Makarand P.
• Granted Patent: US 7,304,099 B2
• Time in Patent Office: Days
• US Class Current: 523/161
• CPC Class Codes: C09D 11/40 Ink-sets specially adapted for multi-colour inkjet printing

Abstract

The invention relates to an improved system for inkjet printing which results in images with increased permanence as measured by transfer of color from the image when the image is subjected to mechanical and/or chemical abrasion. The invention provides a fusible material that may be combined with any or all of the color inks used to create the image, or it may be used as a colorless fluid applied pre- or post-printing. The permanence of images produced by the system are comparable to those produced by electrophotography.

The invention also relates to a printing apparatus that contains a means for fusing the image using heat applied after the printed substrate is ejected from the printer. Methods for utilizing these improvements and examples of them are described.

Claims

1. An ink composition for inkjet printing comprising water, a co-solvent, and a fusible material;

wherein said ink produces a permanent image on a substrate;

wherein said permanence is measured as the amount of transference of color from said substrate when said image printed thereon is subjected to chemical and/or mechanical abrasion and measured in units of milli-optical density of less than 50.

2. The ink composition of claim 1 wherein said ink further comprises a colorant.

3. The ink composition of claim 1 wherein said fusible has a glass transition temperature ranging from between about 40 to about 140 degrees C.

4. The ink composition of claim 3 wherein said fusible has a glass transition temperature ranging from between about 50 to about 90 degrees C.

5. The ink composition according to claim 2 further comprising additives selected from the group consisting of biocides, viscosity modifiers, materials for pH adjustment, sequestering agents, preservatives, surfactants, and mixtures thereof.

6. The ink composition according to claim 3 wherein said fusible material is an emulsion polymer synthesized from components selected from the group consisting of:

a) alkyl methacrylates comprising alkyl groups with from one to about twelve alkyl groups;

b) vinyl aromatic monomers;

c) polymerizable surfactants with both hydrophilic and hydrophobic moieties; and

d) mixtures thereof.

7. The ink composition of claim 6 wherein, if used:

a) said alkyl methacrylate is selected from the group consisting of methyl methacrylate, butyl methacrylate, hexyl acrylate, and mixtures thereof;

b) said vinyl aromatic monomer is selected from the group consisting of styrene, substituted styrene, divinyl benzene, vinyltoluene, vinyl naphthalene, polyvinylbenzenes, and isomers thereof; and

c) said polymerizable surfactant comprises polyethylene glycol as a hydrophilic group and an octyl or nonyl phenol as a hydrophobic group, and mixtures thereof.

8. The ink composition of claim 1 wherein said co-solvent is selected from the group consisting of aliphatic alcohols, aromatic alcohols, diols, glycol ethers, polyglycol ethers, caprolactams, formamides, acetamides, primary aliphatic alcohols, secondary aliphatic alcohols, 1,2-alcohols, 1,3-alcohols, 1,5-alcohols, ethylene glycol alkyl ethers, propylene glycol alkyl ethers, higher homologs of polyethylene glycol alkyl ethers, N-alkyl caprolactams, unsubstituted caprolactams, substituted and unsubstituted formamides, substituted and unsubstituted acetamides, polyethylene glycol, and mixtures thereof.

9. The ink composition according to claim 3 wherein said fusible material is an emulsion polymer synthesized from components selected from the group consisting of:

polyoxazolins, urethan/acrylic block or blended polymers, polycarbonates, polyvinylpyrrolidine, styrene-butadiene latexes, PEG-amine modified and/or diamine cross linked polyene-maleic anhydride, ethylene maleic anhydride, octadecene-maleic anhydride, rosin-maleic anhydride polymers, and mixtures thereof.

10. A 5^th pen composition for use with inkjet ink compositions comprising water, a co-solvent, and a fusible material wherein said 5^th pen composition is deposited onto a substrate either before or after a color-containing ink and wherein said 5^th pen composition produces a permanent image on said substrate;

wherein said permanence is measured as the amount of transference of color from said substrate when said color-containing ink on said substrate is subjected to chemical and/or mechanical abrasion and measured in units of milli-optical density of less than 50.

11. A 5^th pen composition according to claim 10 which is deposited onto a substrate in an amount ranging from about 0.1 to about 4 times the amount of color-containing ink.

12. The 5^th pen composition according to claim 10 wherein said fusible material has a glass transition temperature ranging from between about 40 to about 140 degrees C.

13. The 5^th pen composition according to claim 12 wherein said fusible material has a glass transition temperature ranging from between about 50 to about 90 degrees C.

14. The 5^th pen composition according to claim 10 wherein said fusible material is an emulsion polymer synthesized from components selected from the group consisting of:

e) alkyl acrylate and methacrylates comprising alkyl groups with from one to about twelve alkyl groups;

f) vinyl aromatic monomers;

g) polymerizable surfactants with both hydrophilic and hydrophobic moieties; and

h) mixtures thereof.

15. The 5^th pen composition of claim 14 wherein, if used:

d) said alkyl methacrylate is selected from the group consisting of methyl methacrylate, butyl acrylate, butyl methacrylate, hexyl acrylate, and mixtures thereof;

e) said vinyl aromatic monomer is selected from the group consisting of styrene, substituted styrene, divinyl benzene, vinyltoluene, vinyl naphthalene, polyvinylbenzenes, and isomers thereof; and

f) said polymerizable surfactant comprises polyethylene glycol as a hydrophilic group and an octyl or nonyl phenol as a hydrophobic group, and mixtures thereof.

16. The 5^th pen composition of claim 10 wherein said co-solvent is selected from the group consisting of aliphatic alcohols, aromatic alcohols, diols, glycol ethers, polyglycol ethers, caprolactams, formamides, acetamides, primary aliphatic alcohols, secondary aliphatic alcohols, 1,2-alcohols, 1,3-alcohols, 1,5-alcohols, ethylene glycol alkyl ethers, propylene glycol alkyl ethers, higher homologs of polyethylene glycol alkyl ethers, N-alkyl caprolactams, unsubstituted caprolactams, both substituted and unsubstituted formamides, both substituted and unsubstituted acetamides, polyethylene glycol, and mixtures thereof.

17. The 5^th pen composition according to claim 10 wherein said fusible material is an emulsion polymer synthesized from components selected from the group consisting of:

polyoxazolins, urethan/acrylic block or blended polymers, polycarbonates, polyvinylpyrrolidine, styrene-butadiene latexes, PEG-amine modified and/or diamine cross linked polyene-maleic anhydride, ethylene maleic anhydride, octadecene-maleic anhydride, rosin-maleic anhydride polymers, and mixtures thereof.

19. The method of claim 18 wherein said permanent image is created on said substrate by applying a color-containing ink composition and a fusible material;

wherein said fusible material is applied before or after said color-containing ink or is contained in said color-containing ink composition and wherein a heat source is applied to said substrate which fuses the image onto the substrate.

20. The method for producing permanent images of claim 18 said heat source is a fuser which is part of said inkjet printer.

21. The method for creating permanent images on a substrate according to claim 18 wherein said fusible material is contained in at least one color-containing ink.

22. The method of claim 18 wherein said fusible material is contained in a 5th pen composition which is in addition to said color-containing ink composition.

18. A method for creating permanent images on a variety of substrates with inkjet printers wherein said inkjet printer contains a color-containing ink composition and a fusible material composition and wherein said image undergoes minimal transference of color upon chemical or mechanical abrasion as measured by mOD values ranging between 0 and 50.

23. A printing system for thermal or piezo inkjet printers which comprises:

a) a water based ink set of cyan, magenta, yellow, and black;

b) a fusible material which may be added to at lease one of said inks of a) or may be incorporated in a colorless water-based 5^th pen composition;

c) a printing apparatus equipped with a means for fusion of the image onto a printed substrate resulting in a permanent image with minimal transference of color upon chemical and/or mechanical abrasion as measured by mOD values ranging between 0 and 50.