Magnetic recording layer formulation for tape media

Patent metadata

Field	Value
Publication number	US-11158339-B2
Application number	US-201916546123-A
Country	US
Kind code	B2
Filing date	Aug 20, 2019
Priority date	Aug 20, 2019
Publication date	Oct 26, 2021
Grant date	Oct 26, 2021

Abstract

A product, according to one approach, includes a recording layer. The recording layer includes encapsulated nanoparticles each comprising a magnetic nanoparticle encapsulated by an encapsulating layer. A polymeric binder binds the encapsulated nanoparticles. A product, according to another approach, includes a recording layer. The recording layer includes encapsulated nanoparticles each comprising a magnetic nanoparticle encapsulated by an encapsulating layer, and a polymeric binder binding the encapsulated nanoparticles. An average diameter of the magnetic nanoparticles is in a range of 2 nanometers to 20 nanometers. An average thickness of the recording layer is less than 0.2 microns.

First claim

What is claimed is:

1. A product, comprising:
a recording layer comprising:
encapsulated nanoparticles each comprising a magnetic nanoparticle encapsulated by an aromatic polymer-based encapsulating layer, and
a polymeric binder binding the encapsulated nanoparticles.

2. The product as recited in claim 1 , wherein the magnetic nanoparticles include at least one magnetic material selected from the group consisting of: nickel, cobalt, and iron.

3. The product as recited in claim 1 , wherein the magnetic nanoparticles include at least one magnetic material selected from the group consisting of: Co 3 O 4 , CoFe, Fe 2 O 3 , Fe 3 O 4 , and Co(fcc).

4. The product as recited in claim 1 , wherein an average diameter of the magnetic nanoparticles is in a range of 2 nanometers to 20 nanometers.

5. A product, comprising:
a recording layer comprising:
encapsulated nanoparticles each comprising a magnetic nanoparticle encapsulated by an encapsulating layer, and
a polymeric binder binding the encapsulated nanoparticles,
wherein the encapsulating layer is a layer selected from the group consisting of: a polyaromatic film, and a graphite-like dominated continuous film.

6. The product as recited in claim 1 , wherein an average thickness of each encapsulating layer is less than 1 nanometer.

7. The product as recited in claim 1 , wherein the polymeric binder which binds the encapsulated nanoparticles is a radiation curable rubbery acrylic polymer.

8. The product as recited in claim 1 , wherein an average thickness of the recording layer is less than 0.2 microns.

9. The product as recited in claim 1 , wherein an average thickness of the recording layer is less than 0.1 microns.

10. The product as recited in claim 1 , wherein no wear particles are present in the recording layer.

11. The product as recited in claim 1 , wherein no wear particles are present in the product.

12. The product as recited in claim 1 , comprising an underlayer, the recording layer being formed on the underlayer.

13. The product as recited in claim 12 , wherein the recording layer is substantially not physically intermixed with the underlayer in the product such that an upper surface of the underlayer is substantially flat, with a modulation of less than about 25% of a thickness of an interfacial boundary between the underlayer and the recording layer.

14. The product as recited in claim 12 , wherein the underlayer is electrically conductive for assisting in dissipating a charge in the product.

15. The product as recited in claim 12 , wherein the underlayer comprises magnetic nanoparticles having an average magnetic field strength of less than 200 Oersted (Oe).

16. The product as recited in claim 1 , comprising lubricant molecules grafted to and/or embedded in a surface of the recording layer, wherein an amount of the lubricant molecules along the surface of the recording layer is less than an amount to form a continuous lubricant film along the surface of the recording layer.

17. The product as recited in claim 1 , comprising lubricant molecules grafted to a surface of the recording layer.

18. The product as recited in claim 1 , wherein the recording layer is part of a magnetic recording tape.

19. A product, comprising:
a recording layer comprising:
encapsulated nanoparticles each comprising a magnetic nanoparticle encapsulated by an aromatic polymer based encapsulating layer, and
a polymeric binder binding the encapsulated nanoparticles,

wherein an average diameter of the magnetic nanoparticles is in a range of 2 nanometers to 20 nanometers,
wherein an average thickness of the recording layer is less than 0.2 microns.

20. The product as recited in claim 19 , wherein the encapsulating layer is a layer selected from the group consisting of: a polyaromatic film and a graphite-like dominated continuous film.

21. The product as recited in claim 19 , wherein the recording layer is formed directly on an underlayer, wherein the recording layer is substantially not physically intermixed with the underlayer in the product whereby interlayer turbidity is minimized, wherein an upper surface of the underlayer is substantially flat, with a modulation of less than about 25% of a thickness of an interfacial boundary between the underlayer and the recording layer.

22. The product as recited in claim 19 , wherein the polymeric binder includes a material selected from the group consisting of: a radiation curable rubbery acrylic terminated aliphatic polyester and an aliphatic polyether polymer.

23. The product as recited in claim 19 , wherein no wear particles are present in the product.

24. The product as recited in claim 19 , comprising lubricant molecules grafted to and/or embedded in a surface of the recording layer.

25. The product as recited in claim 24 , wherein an amount of the lubricant molecules along the surface of the recording layer is less than an amount to form a continuous lubricant film along the surface of the recording layer.

Assignees

• IBM

Inventors

• Bradshaw Richard

Classifications

• H01F1/113

  in a bonding agent · CPC title

• H01F1/061

  with a protective layer · CPC title

• G11B5/73

  Base layers {, i.e. all non-magnetic layers lying under a lowermost magnetic recording layer, e.g. including any non-magnetic layer in between a first magnetic recording layer and either an underlying substrate or a soft magnetic underlayer} · CPC title

• G11B5/716

  characterised by two or more magnetic layers · CPC title

• G11B5/714

  characterised by the dimension of the magnetic particles · CPC title