Acrylate ink compositions for ink-based digital lithographic printing

Patent metadata

Field	Value
Publication number	US-9815992-B2
Application number	US-201514610437-A
Country	US
Kind code	B2
Filing date	Jan 30, 2015
Priority date	Jan 30, 2015
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

An ink composition, including 30% or less pigment, 10% or less dispersant, between 40% and 80% acrylate, 12% or less photoinitiator, and having a viscosity between 2×10 6 cP and 5×10 7 cP at 25° C., and between 2.×10 5 cP and 4.×10 6 cP at 60° C., and a 60 second tack between 40 and 65 g-m at 25° C., and between 10 and 20 g-m at 60° C.

First claim

The invention claimed is:

1. An ink composition, comprising:
20% or less by weight pigment, based on a total weight of the ink composition;
10% or less by weight dispersant, based on the total weight of the ink composition;
between 50% and 75% by weight acrylate, based on the total weight of the ink composition, wherein the acrylate comprises propoxylated (6) trimethylolpropane triacrylate, tetra-functional acrylated polyester oligomer and a high-viscosity di-functional acrylated polyester oligomer; and
between 5% and 10% by weight photoinitiator, based on the total weight of the ink composition,
wherein a near-zero shear viscosity of the ink composition is:
between 2×10 6 cP and 5×10 7 cP at 25° C., and
between 2×10 5 cP and 4×10 6 cP at 60° C., and

wherein a 60 second tack of the ink composition is:
between 40 g-m and 65 g-m at 25° C., and
between 10 g-m and 20 g-m at 60° C.

2. The ink composition of claim 1 , further comprising:
1.5% or less by weight stabilizer, based on the total weight of the ink composition; and
12% or less by weight rheology modifier, based on the total weight of the ink composition.

3. The ink composition of claim 2 , comprising:
between 15% and 20% pigment;
between 4% and 8% dispersant;
between 60% and 70% acrylate;
between 5% and 10% photoinitiator;
between 0.1% and 0.3% stabilizer; and
3% or less rheology modifier,
wherein the ink composition has a near-zero shear viscosity between 4×10 6 cP and 1×10 7 cP at 25° C., and between 4×10 5 cP and 8×10 5 cP at 60° C., and
wherein a 60 second tack of the ink composition is between 45 g-m and 55 g-m at 25° C., and between 10 g-m and 15 g-m at 60° C.

4. The ink composition of claim 3 , wherein the acrylate further comprises at least one of an acrylate monomer, acrylate polymer, acrylate oligomer, a difunctional acrylate monomer, and mixtures thereof.

5. The ink composition of claim 1 , wherein the high-viscosity di-functional acrylated polyester oligomer has a viscosity of at least 11,000 cps at 60° C.

6. An ink composition, essentially consisting of:
20% or less by weight pigment, based on a total weight of the ink composition;
10% or less by weight dispersant, based on the total weight of the ink composition;
between 50% and 75% by weight acrylate, based on the total weight of the ink composition,
wherein the acrylate comprises a trifunctional acrylate monomer and a high-viscosity, di-functional acrylated polyester oligomer; and,
optionally, one or more acrylates selected from the group consisting of an acrylate monomer, acrylate polymer, acrylate oligomer, and a difunctional acrylate monomer,
between 5% and 10% by weight photoinitiator, based on the total weight of the ink composition;
1.5% or less by weight stabilizer, based on the total weight of the ink composition;
and 12% or less by weight rheology modifier, based on the total weight of the ink composition,
wherein a near-zero shear viscosity of the ink composition is:
between 2×10 6 cP and 5×10 7 cP at 25° C., and
between 2×10 5 cP and 4×10 6 cP at 60° C.,
and wherein a 60 second tack of the ink composition is:
between 40 g-m and 65 g-m at 25° C., and
between 10 g-m and 20 g-m at 60° C.

7. The ink composition of claim 6 , essentially consisting of:
between 15% and 20% pigment;
between 4% and 8% dispersant;
between 60% and 70% acrylate;
between 5% and 10% photoinitiator;
between 0.1% and 0.3% stabilizer; and
3% or less rheology modifier,
wherein the ink composition has a near-zero shear viscosity between 4×10 6 cP and 1×10 7 cP at 25° C., and between 4×10 5 cP and 8×10 5 cP at 60° C., and
wherein a 60 second tack of the ink composition is between 45 g-m and 55 g-m at 25° C., and between 10 g-m and 15 g-m at 60° C.

8. The ink composition of claim 6 , wherein the high-viscosity di-functional acrylated polyester oligomer has a viscosity of at least 11,000 cps at 60° C.

9. A method of printing using a variable data digital lithographic printing device, comprising:
applying an ink composition to a reimageable surface of an imaging member; and
transferring the ink composition from the reimageable surface to a substrate, wherein the ink composition does not require pre-curing before transferring the ink composition from the reimageable surface to the substrate, wherein the ink composition comprises:
20% or less by weight pigment, based on a total weight of the ink composition;
10% or less by weight dispersant, based on the total weight of the ink composition;
between 50% and 75% by weight acrylate, based on the total weight of the ink composition,
wherein the acrylate comprises a trifunctional acrylate monomer and a high-viscosity, di-functional acrylated polyester oligomer
and optionally one or more acrylates selected from the group consisting of an acrylate monomer, acrylate polymer, acrylate oligomer, and a difunctional acrylate monomer,
between 5% and 10% by weight photoinitiator, based on the total weight of the ink composition;
1.5% or less by weight stabilizer, based on the total weight of the ink composition; and
12% or less by weight rheology modifier, based on the total weight of the ink composition,
wherein a near-zero shear viscosity of the ink composition is:
between 2×10 6 cP and 5×10 7 cP at 25° C., and between 2×10 5 cP and 4×10 6 cP at 60° C.

and wherein a 60 second tack of the ink composition is:
between 40 and 65 g-m at 25° C.,
and between 10 and 20 g-m at 60° C.

10. The method of claim 9 , wherein the ink composition consists essentially of:
between 15% and 20% pigment;
between 4% and 8% dispersant;
between 60% and 70% acrylate;
between 5% and 10% photoinitiator;
between 0.1% and 0.3% stabilizer; and
3% or less rheology modifier;
wherein the ink composition has a near-zero shear viscosity between 4×10 6 cP and 1×10 7 cP at 25° C., and between 4×10 5 cP and 8×10 5 cP at 60° C., and wherein a 60 second tack of the ink composition is between 45 g-m and 55 g-m at 25° C., and between 10 g-m and 15 g-m at 60° C.

11. The method of claim 9 , wherein the high-viscosity di-functional acrylated polyester oligomer has a viscosity of at least 11,000 cps at 60° C.

12. A method of printing using a variable data digital lithographic printing device, comprising:
applying an ink composition at a first temperature to a reimageable surface of an imaging member; and
transferring the ink composition from the reimageable surface to a substrate at a second temperature,
wherein the ink composition does not require pre-curing before transferring the ink composition from the reimageable surface to the substrate,
wherein the ink composition comprises:
20% or less by weight pigment, based on a total weight of the ink composition;
10% or less by weight dispersant, based on the total weight of the ink composition;
between 50% and 75% by weight acrylate, based on the total weight of the ink composition, wherein the acrylate comprises propoxylated (6) trimethylolpropane triacrylate, tetra-functional acrylated polyester oligomer and a high-viscosity di-functional acrylated polyester oligomer; and
between 5% and 10% or less by weight photoinitiator, based on the total weight of the ink composition,
wherein a near-zero shear viscosity of the ink composition is
between 2×10 6 cP and 5×10 7 cP at 25° C., and
between 2×10 5 cP and 4×10 6 cP at 60° C., and

wherein a 60 second tack of the ink composition is
between 40 g-m and 65 g-m at 25° C., and
between 10 g-m and 20 g-m at 60° C.

13. The method of claim 12 , wherein the composition comprises:
between 15% and 20% pigment;
between 4% and

Assignees

• Xerox Corp

Inventors

• Allen C Geoffrey
• Moorlag Carolyn
• Birau Mihaela Maria
• Magdalinis Aurelian Valeriu

Classifications

• C09D11/326

  characterised by the pigment dispersant · CPC title

• C09D11/101 Primary

  Inks specially adapted for printing processes involving curing by wave energy or particle radiation, e.g. with UV-curing following the printing · CPC title

• C09D11/037

  characterised by the pigment · CPC title

• B41F7/02

  for offset printing · CPC title