Process for the production of nano-fibrillar cellulose gels

Patent metadata

Field	Value
Publication number	US-10294371-B2
Application number	US-201414474749-A
Country	US
Kind code	B2
Filing date	Sep 2, 2014
Priority date	Mar 30, 2009
Publication date	May 21, 2019
Grant date	May 21, 2019

Abstract

The present invention relates to a process for the production of nano-fibrillar cellulose gels by providing cellulose fibers and at least one filler and/or pigment; combining the cellulose fibers and the at least one filler and/or pigment; and fibrillating the cellulose fibers in the presence of the at least one filler and/or pigment until a gel is formed, as well as the nano-fibrillar cellulose gel obtained by this process and uses thereof.

First claim

The invention claimed is:

1. A nano-fibrillar cellulose gel obtained by the process comprising the steps of:
(a) providing cellulose fibres contained in pulps selected from the group consisting of eucalyptus pulp, spruce pulp, pine pulp, beech pulp, hemp pulp, cotton pulp, or any mixture thereof;
(b) providing a filler;
(c) combining the cellulose fibres of step (a) and the filler; and
(d) fibrillating the cellulose fibres in an aqueous environment in the presence of the filler from step (c) until a nano-fibrillar cellulose gel is formed;
wherein the formation of the gel is verified by monitoring the viscosity of the mixture in dependence of the shearing rate, wherein the viscosity decrease of the mixture upon step-wise increase of the shearing rate is stronger than the corresponding viscosity increase upon subsequent step-wise reduction of the shearing rate over at least part of the shear rate range as shearing approaches zero;
wherein the filler is natural ground calcium carbonate,
wherein in step (d) the weight ratio of fibres to filler on a dry weight basis is from 1:33 to 10:1, wherein the Brookfield viscosity of the nano-fibrillar cellulose gel formed in step (d) is lower than the Brookfield viscosity of a corresponding nano-fibrillar cellulose suspension having been fibrillated in the absence of the filler.

2. The gel according to claim 1 , wherein the cellulose fibres in step (a) are provided in the form of a suspension.

3. The gel according to claim 1 , wherein the cellulose fibres in step (a) are provided in the form of a suspension at a solids content of from 0.2 to 35 wt.-%.

4. The gel according to claim 1 , wherein the cellulose fibres in step (a) are provided in the form of a suspension at a solids content of from 0.25 to 10 wt.-%.

5. The gel according to claim 1 , wherein the cellulose fibres in step (a) are provided in the form of a suspension at a solids content of from 0.5 to 5 wt.-%.

6. The gel according to claim 1 , wherein the cellulose fibres in step (a) are provided in the form of a suspension at a solids content of from 1 to 4 wt.-%.

7. The gel according to claim 1 , wherein the cellulose fibres in step (a) are provided in the form of a suspension at a solids content of from 1.3 to 3 wt.-%.

8. The gel according to claim 1 , wherein the filler in step (b) is natural ground calcium carbonate selected from marble, limestone and/or chalk.

9. The gel according to claim 1 , wherein the filler in step (b) is in the form of particles having a median medium particle size of from 0.01 to 15 μm.

10. The gel according to claim 1 , wherein the filler in step (b) is in the form of particles having a median medium particle size of from 0.1 to 10 μm.

11. The gel according to claim 1 , wherein the filler in step (b) is in the form of particles having a median medium particle size of from 0.3 to 5 μm.

12. The gel according to claim 1 , wherein the filler in step (b) is in the form of particles having a median medium particle size of from 0.5 to 4 μm.

13. The gel according to claim 1 , wherein the filler in step (b) comprises a dispersing agent.

14. The gel according to claim 13 , wherein the dispersing agent is selected from homopolymers or copolymers of polycarboxylic acids and/or their salts or esters, acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, acryl amide or acrylic esters, or mixtures thereof; alkali polyphosphates, phosphonic-, citric- and tartaric acids, salts or esters thereof; or mixtures thereof.

15. The gel according to claim 1 , wherein in step (d) the weight ratio of fibres to filler on a dry weight basis is from 1:10 to 7:1.

16. The gel according to claim 1 , wherein in step (d) the weight ratio of fibres to filler on a dry weight basis is from 1:5 to 5:1.

17. The gel according to claim 1 , wherein in step (d) the weight ratio of fibres to filler on a dry weight basis is from 1:3 to 3:1.

18. The gel according to claim 1 , wherein in step (d) the weight ratio of fibres to filler on a dry weight basis is from 1:2 to 2:1.

19. The gel according to claim 1 , wherein in step (d) the weight ratio of fibres to filler on a dry weight basis is from 1:1.5 to 1.5:1.

20. The gel according to claim 1 , wherein the fibrillating in step (d) is carried out by a homogenizer or an ultra fine friction grinder.

21. A material composite, plastic, paint, rubber, concrete, ceramic, adhesive, food or wound-healing composite comprising the nano-fibrillar cellulose gel according to claim 1 .

Assignees

• Fiberlean Tech Ltd

Inventors

• Gane Patrick A C
• Schoelkopf Joachim
• Gantenbein Daniel
• Schenker Michel

Classifications

• A61P17/02

  for treating wounds, ulcers, burns, scars, keloids, or the like · CPC title

• C08J3/00

  Processes of treating or compounding macromolecular substances · CPC title

• C08J5/005

  Reinforced macromolecular compounds with nanosized materials, e.g. nanoparticles, nanofibres, nanotubes, nanowires, nanorods or nanolayered materials · CPC title

• D21B1/04

  by dividing raw materials into small particles, e.g. fibres (breaking-up or cutting wood or the like by dry methods B27L; mechanical separation of fibres from plant material D01B1/00; hackling or heckling machines D01B5/00) · CPC title

• A23V2002/00

  Food compositions, function of food ingredients or processes for food or foodstuffs · CPC title