Roll and its use

Patent metadata

Field	Value
Publication number	US-10900173-B2
Application number	US-201816201874-A
Country	US
Kind code	B2
Filing date	Nov 27, 2018
Priority date	Nov 28, 2017
Publication date	Jan 26, 2021
Grant date	Jan 26, 2021

Abstract

The present invention relates to a roll for use in a manufacture of a fibrous web comprising cellulosic fibers. The roll comprises a roll body with a cylindrical surface, and a roll cover, which is arranged to cover the cylindrical surface of the roll body. The cover comprises a functional layer, which comprises a polymer matrix and filler particles embedded in the polymer matrix. The filler particles comprise hollow spherical particles of aluminium oxide, titanium oxide, zirconium oxide and/or silicon carbide, which hollow particles have a particle size of ≥200 μm.

First claim

I claim:

1. A paper or board machine roll for use in the manufacture of a paper or board web comprising cellulosic fibers, the roll comprising:
a roll body with a cylindrical surface;
a roll cover covering the cylindrical surface of the roll body;
wherein the cover comprises a functional layer which comprises a polymer matrix and filler particles embedded in the polymer matrix;
wherein the filler particles comprise hollow spherical particles made of a material selected from the group consisting of: aluminum oxide, titanium oxide, zirconium oxide and silicon carbide; and
wherein the hollow spherical particles comprise 2.5 to less than 50 weight % of the matrix and have a particle size of less than or equal to 200 micrometers.

2. The paper or board machine roll of claim 1 wherein the hollow spherical particles are at least 50 to 90% of all filler particles in the matrix.

3. The paper or board machine roll of claim 2 wherein the hollow spherical particles are at least 80 to 90% of all filler particles in the matrix.

4. The paper or board machine roll of claim 3 wherein the hollow spherical particles are at least 90% of all filler particles in the matrix.

5. The paper or board machine roll of claim 1 wherein the hollow spherical particles comprise a shell wall surrounding an internal closed cavity, wherein the shell wall has a thickness in the range of 1-50 μm.

6. The paper or board machine roll of claim 1 wherein the hollow spherical particles have a particle size in a range of 5-40 μm.

7. The paper or board machine roll of claim 1 wherein the hollow spherical particles have a hardness of greater than 8.5 Moh.

8. The paper or board machine roll of claim 1 wherein the hollow spherical particles are particles of aluminum oxide.

9. The paper or board machine roll of claim 1 wherein the polymer matrix of the functional layer is rubber, or thermosetting or thermoplastic polymer.

10. The paper or board machine roll of claim 9 wherein the polymer matrix of the functional layer is rubber, and wherein the functional layer comprises at maximum 40 weight-percent of hollow spherical particles.

11. The paper or board machine roll of claim 9 wherein the roll is a calender roll.

12. The paper or board machine roll of claim 9 wherein the polymer matrix of the functional layer is polyurethane resin and wherein the functional layer comprises at maximum 10 weight-percent of hollow spherical particles, embedded into the matrix.

13. The paper or board machine roll of claim 9 wherein the roll is a press roll, suction roll, sizer roll or a coater roll.

14. The paper or board machine roll of claim 1 wherein the polymer matrix of the functional layer further comprises at least one of: additional filler, particles, and additives.

15. The paper or board machine roll of claim 1 wherein the hollow spherical particles are surface modified.

16. The paper or board machine roll of claim 1 wherein the functional layer of the roll cover has a thickness of 10-40 mm, and wherein in addition to the functional layer the roll cover comprises a base layer, which is arranged in contact with the roll surface and an optional intermediate layer, which is arranged between the functional layer and the base layer.

17. The paper or board machine roll of claim 1 wherein the polymer matrix is epoxy, and the hollow spherical particles comprise 5 to less than 50 weight % of the matrix and the hollow spherical particles have a size of 1-100 micrometers and the hollow spherical particles have a shell wall surrounding an internal closed cavity, wherein the shell wall has a thickness in the range of 1-50 micrometers.

18. The paper or board machine roll of claim 1 wherein the polymer matrix is rubber, and the hollow spherical particles comprise 2.5 to less than 40 weight % of the matrix and the hollow spherical particles have a shell wall surrounding an internal closed cavity, wherein the shell wall has a thickness in the range of 2-25 micrometers.

19. The paper or board machine roll of claim 1 wherein the polymer matrix is polyurethane, and the hollow spherical particles comprise 2.5 to less than 10 weight % of the matrix and have a particle size of 4-40 micrometers and the hollow spherical particles have a shell wall surrounding an internal closed cavity, wherein the shell wall has a thickness in the range of 1-30 micrometers.

20. A roll in a paper machine, board machine, tissue machine or in a converting machine for a fibrous cellulosic web, the roll comprising:
a roll body with a cylindrical surface;
a roll cover covering the cylindrical surface of the roll body;
wherein the cover comprises a functional layer which comprises a polymer matrix and filler particles embedded in the polymer matrix;
wherein the filler particles comprise hollow spherical particles of 2.5 to less than 50 weight % of the matrix and are made of a material selected from the group consisting of: aluminum oxide, titanium oxide, zirconium oxide and silicon carbide; and
wherein the hollow spherical particles have a particle size of less than or equal to 200 micrometers.

21. A method of forming or converting a fibrous cellulosic web comprising engaging a roll with a web within a paper machine, a board machine, a tissue machine or in a converting machine, the roll comprising:
a roll body with a cylindrical surface;
a roll cover covering the cylindrical surface of the roll body;
wherein the cover comprises a functional layer which comprises a polymer matrix and filler particles embedded in the polymer matrix;
wherein the filler particles comprise hollow spherical particles made of a material selected from the group consisting of: aluminum oxide, titanium oxide, zirconium oxide and silicon carbide; and
wherein the hollow spherical particles comprise 2.5 to less than 50 weight % of the matrix and the hollow spherical particles have a particle size of less than or equal to 200 micrometers.

Assignees

• Valmet Technologies Inc

Inventors

• Turunen Jani

Classifications

• B32B2264/102

  Oxide or hydroxide · CPC title

• D21F1/40 Primary

  Rolls · CPC title

• D21F3/105

  Covers thereof · CPC title

• D21H23/58 Primary

  Details thereof, e.g. surface characteristics, peripheral speed · CPC title

• C08K7/24

  inorganic · CPC title