Curable overcoat for wax-based inks

• US 20070120922A1
• Filed: 11/30/2005
• Published: 05/31/2007
• Est. Priority Date: 11/30/2005
• Status: Active Grant

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Belelie, Jennifer, Odell, Peter
• Granted Patent: US 7,578,587 B2
• Time in Patent Office: Days
• US Class Current: 347/100
• CPC Class Codes: B41M 7/0045 using protective coatings or film forming compositions cured by mechanical wave energy, e.g. ultrasonics, cured by electromagnetic radiation or waves, e.g. ultraviolet radiation, electron beams, or cured by magnetic or electric fields, e.g. electric discharge, plasma
• CPC Class Codes: C09D 11/101 Inks specially adapted for printing processes involving curing by wave energy or particle radiation, e.g. with UV-curing following the printing
• CPC Class Codes: C09D 11/12 based on waxes or bitumen
• CPC Class Codes: C09D 11/34 Hot-melt inks
• CPC Class Codes: G03G 8/00 Layers covering the final reproduction, e.g. for protecting, for writing thereon

Abstract

An ink jettable overprint composition includes at least one of a polymerizable monomer and/or a polymerizable oligomer; at least one photoinitiator; and at least one wax.

Claims

1. An ink jettable overprint composition, comprising:

at least one of a polymerizable monomer and/or a polymerizable oligomer;

at least one photoinitiator; and

at least one wax.

2. The composition of claim 1, wherein the overprint composition has a viscosity ranging from about 2 cP to about 20 cP at a temperature ranging from about 70°

C. to about 110°

C.

3. The composition of claim 1, wherein the wax increases an affinity of the overcoat composition with an underlying printed image.

4. The composition of claim 1, wherein the wax is functionalized with at least one polymerizable group.

5. The composition of claim 1, wherein the wax comprises a functional group selected from the group consisting of carboxylic acid and hydroxyl groups.

6. The composition of claim 1, wherein the overprint composition comprises at least one polymerizable monomer and/or at least one polymerizable oligomer.

7. The composition of claim 1, wherein the overprint composition comprises:

from about 20 to about 95 wt % of a polymerizable monomer;

from about 0 to about 30 wt % polymerizable oligomer;

from about 0.5 to about 15 wt % of photoinitiator; and

from about 0.05 to about 60 wt % of wax.

8. The composition of claim 1, wherein the overprint composition comprises:

from about 30 to about 90 wt % of a polymerizable monomer;

from about 0 to about 20 wt % polymerizable oligomer;

from about 1 to about 15 wt % of photoinitiator; and

from about 0.1 to about 60 wt % of wax.

9. The composition of claim 1, further comprising a component that reduces a coefficient of friction of the overprint coating composition.

10. The composition of claim 1, wherein the monomer is cationically curable.

11. The composition of claim 1, wherein the monomer is radically curable.

12. The composition of claim 1, further comprising an amine synergist.

13. The composition of claim 1, wherein the photoinitiator is selected from the group consisting of triarylsulfonium salts, diaryliodonium salts, aryldiazonium salts, triarylselenonium salts, dialkylphenacylsulphonium salts, triarylsulphoxonium salts, aryloxydiarylsulphonoxonium salts, and dialkylphenacylsulphoxonium salts, wherein the salts are formed with ions such as BF₄⁻

, PF₆⁻

, AsF₆⁻

, SbF₆⁻

.

14. The composition of claim 1, wherein the photoinitiator is selected from the group consisting of hydroxycyclohexylphenyl ketones, trimethylbenzophenones, polymeric hydroxy ketones, trimethylbenzoylphenylphosphine oxides, and mixtures thereof.

15. The composition of claim 1, wherein the photoinitiator is selected from the group consisting of 2,4,6-trimethylbenzophenone, 4-methylbenzophenone, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, alpha-amino ketone, 4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2-propyl)ketone, 2-isopropyl-9H-thioxanthen-9-one, and mixtures thereof.

16. The composition of claim 1, wherein the radiation curable monomer is present and is selected from the group consisting of neopentyl glycol diacrylates, butanediol diacrylates, trimethylolpropane triacrylates, and glyceryl triacrylates.

17. A method of ink jet printing, comprising:

providing an ink jettable overprint composition according to claim 1;

ink jetting the overprint composition onto a substrate having an image thereon; and

exposing the image to a radiation source for sufficient time to at least substantially cure the radiation curable components of the overprint composition.

18. The method of claim 17, wherein the image is wax-based.

19. The method of claim 17, wherein the image is ink-based.

20. The method of claim 17, wherein the radiation source is an ultraviolet light.

21. The method of claim 17, wherein the ink jet is a thermal ink jet printer or a piezoelectric ink jet printer.

23. A toner-based or ink-based print, comprising a substrate with a toner-based or ink-based image thereon coated with the overprint composition of claim 1, wherein, upon curing, the toner or ink on the print resists smearing upon overwriting.

22. A system for creating an image on a substrate, comprising:

an image generating component,

a substrate for receiving an image generated from the image generating component; and

an overprint composition configured for being ink jetted onto the generated image;

wherein the overprint composition comprises;

at least one of a polymerizable monomer and a polymerizable oligomer;

at least one photoinitiator; and

at least one wax.