Primer composition and method

Patent metadata

Field	Value
Publication number	US-10042274-B2
Application number	US-201515522285-A
Country	US
Kind code	B2
Filing date	Jan 19, 2015
Priority date	Jan 19, 2015
Publication date	Aug 7, 2018
Grant date	Aug 7, 2018

Abstract

A method for determining coat weight of a transparent primer coating for liquid electrophotographic printing processes is described, in which an optical brightening agent is added to an aqueous transparent primer composition in an amount of less than 0.1 wt. % based on the total solids content of the primer composition to produce a test composition, the test composition is applied onto a test substrate to produce a transparent primer coating, the fluorescence of the transparent primer coating is measured, and the coat weight of the transparent primer coating based on the fluorescence of the transparent primer coating is determined.

First claim

The invention claimed is:

1. A method for determining coat weight of a transparent primer coating for liquid electrophotographic printing processes, comprising:
(i) adding to an aqueous transparent primer composition an optical brightening agent in an amount of less than 0.1 wt. % based on the total solids content of the primer composition to produce a test composition that includes a balance of water;
(ii) applying the test composition onto a test substrate to produce the transparent primer coating;
(iii) measuring the fluorescence of the transparent primer coating; and
(iv) determining the coat weight of the transparent primer coating based on the fluorescence of the transparent primer coating.

2. The method of claim 1 , wherein the fluorescence of the transparent primer coating is measured directly after the transparent primer coating is produced.

3. The method of claim 1 , wherein the test composition is a transparent or non-pigmented liquid electrophotographic composition.

4. The method of claim 1 , wherein the optical brightening agent is a colourless optical brightening agent.

5. The method of claim 1 , wherein the optical brightening agent is a fluorophore.

6. The method of claim 1 , wherein the optical brightening agent comprises one or more of a triazine stilbene and derivatives thereof, a biphenyl stilbene and derivatives thereof, a coumarin and derivatives thereof, a benzoxazoline and derivatives thereof, a diazole and derivatives thereof, an imidazoline and derivatives thereof, or mixtures thereof.

7. The method of claim 1 , wherein the coat weight of the transparent primer coating is directly proportional to the fluorescence of the transparent primer coating.

8. A method of printing, comprising:
performing the method of claim 1 ;
adjusting a parameter of the coating process based on the determined coat weight;
applying the aqueous primer composition onto a print substrate to produce a primed print substrate; and
printing a liquid electrophotographic composition onto the primed print substrate.

9. The method of claim 8 , wherein adjusting the parameter of the coating process comprises adjusting the amount of the test composition printed onto the print substrate.

10. The method of claim 8 , wherein adjusting the parameter of the coating process comprises adjusting a dosing parameter, a coating temperature, a coating pressure, or any combination thereof.

11. The method of claim 8 , wherein the steps of determining the coat weight and adjusting the parameter of the coating process are repeated before printing the transparent primer composition onto the print substrate.

12. An aqueous transparent primer composition for priming a print substrate for a liquid electrophotographic printing process, the composition comprising:
a polymeric material comprising one or more of a polyethyleneimine, a polyurethane, a polyamide, a polycarbodiimide, a hydrogenated hydrocarbon rosin or rosin ester, and a copolymer of an alkylene monomer and a monomer selected from acrylic acid and methacrylic acid;
an optical brightening agent in an amount of less than 0.1 wt. % based on the total solids content of the primer composition; and
a balance of water.

13. The composition of claim 12 , wherein the optical brightening agent is a colourless optical brightening agent.

14. The composition of claim 12 , wherein the optical brightening agent is a fluorophore.

15. The composition of claim 12 , wherein the optical brightening agent comprises one or more of a triazine stilbene and derivatives thereof, a biphenyl stilbene and derivatives thereof, a coumarin and derivatives thereof, a benzoxazoline and derivatives thereof, a diazole and derivatives thereof, an imidazoline and derivatives thereof, or mixtures thereof.

16. The method of claim 1 , wherein the test substrate is a plastic substrate selected from the group consisting of biaxially oriented polypropylene (BOPP) and polyethylene terephthalate (PET).

Assignees

• Hp Indigo Bv

Inventors

• Tzomik Inna
• Ron Hannoch
• Maor Shani
• Glick Einat
• Stolov Alexander

Classifications

• G03G9/12

  in liquid developer mixtures · CPC title

• G03G7/0053 Primary

  Intermediate layers for image-receiving members · CPC title

• G01N21/8422

  Investigating thin films, e.g. matrix isolation method · CPC title

• G03G8/00

  Layers covering the final reproduction, e.g. for protecting, for writing thereon · CPC title

• G01N2021/8427

  Coatings · CPC title