Non newtonian ballpoint pen ink comprising cellulose nanofibers

Patent metadata

Field	Value
Publication number	US-12297362-B2
Application number	US-202017425064-A
Country	US
Kind code	B2
Filing date	Jan 24, 2020
Priority date	Jan 25, 2019
Publication date	May 13, 2025
Grant date	May 13, 2025

Abstract

There is a non-aqueous gel writing ink having an organic solvent, a coloring agent and a gelling agent, and the gelling agent is non-oxidized cellulose nanofibers. There also is a use of non-oxidized cellulose nanofibers as a gelling agent in a non-aqueous gel writing ink. There is finally a writing instrument having the ink according to the present disclosure.

First claim

The invention claimed is:

1. Non-aqueous gel writing ink comprising an organic solvent, a coloring agent and a gelling agent, wherein the gelling agent comprises non-oxidized cellulose nanofibers, and the non-oxidized cellulose nanofibers have an average particle diameter below 3 micrometers as measured by dynamic light scattering.

2. Non-aqueous gel writing ink according to claim 1 , wherein the non-oxidized cellulose nanofibers are in the form of a dispersion.

3. Non-aqueous gel writing ink according to claim 1 , wherein the fibers of the non-oxidized cellulose nanofibers have a diameter in the range 1-50 nm measured by transmission electron microscope.

4. Non-aqueous gel writing ink according to claim 1 , wherein the non-oxidized cellulose nanofibers content is in the range 0.01-1% by weight relative to the total weight of the ink.

5. Non-aqueous gel writing ink according to claim 1 , wherein the organic solvent is chosen in the group consisting of glycols, alcohols, and mixtures thereof.

6. Non-aqueous gel writing ink according to claim 1 , wherein the organic solvent content is between 35 and 80% by weight, relative to the total weight of the ink.

7. Non-aqueous gel writing ink according to claim 1 , wherein the coloring agent is a dye, a pigment or mixtures thereof.

8. Non-aqueous gel writing ink according to claim 1 , wherein the coloring agent content is between 5 and 30% by weight, relative to the total weight of the ink.

9. Non-aqueous gel writing ink according to claim 1 , wherein the gelling agent comprises also silica particles.

10. Non-aqueous gel writing ink according to claim 1 , further comprising additives.

11. Non-aqueous gel writing ink according to claim 1 , wherein the additive content is between 0 and 30% by weight, relative to the total weight of the ink.

12. Non-aqueous gel writing ink according to claim 1 , wherein its viscosity measured at 20° C. with a cone-and-plate rheometer is between 10,000 and 200,000 mPa·s at a shear rate of 0.01 s −1 and is between 500 and 20,000 mPa·s at a shear rate of 100 s −1 .

13. A writing instrument containing the ink according to claim 1 .

14. Non-aqueous gel writing ink according to claim 1 , wherein the non-oxidized cellulose nanofibers are water-insoluble.

15. Non-aqueous gel writing ink according to claim 1 , wherein the non-oxidized cellulose nanofibers content is in the range 0.05-0.50% by weight relative to the total weight of the ink.

16. Non-aqueous gel writing ink according to claim 9 , wherein the silica particles content is in the range 0.02-1%, relative to the total weight of the ink.

17. Non-aqueous gel writing ink according to claim 9 , wherein the silica particles are hydrophilic silica particles.

Assignees

• SOCIéTé BIC

Inventors

• Caffier Guillaume
• Liu Wing Yam

Classifications

• C09D11/17

  characterised by colouring agents · CPC title

• C08K2201/011

  Nanostructured additives · CPC title

• C08K2201/003

  Additives being defined by their diameter · CPC title

• C08K7/02

  Fibres or whiskers · CPC title

• C08K5/05

  Alcohols; Metal alcoholates · CPC title