Materials with high dielectric constant for magnetic resonance imaging instruments

Patent metadata

Field	Value
Publication number	US-12210076-B2
Application number	US-201917043712-A
Country	US
Kind code	B2
Filing date	Mar 27, 2019
Priority date	Apr 3, 2018
Publication date	Jan 28, 2025
Grant date	Jan 28, 2025

Abstract

The invention relates to a material for use as a pad in high field and/or very high field magnetic resonance imaging instrument, comprising at least one polar solvent having a melting point of 14° C. to 50° C., a dispersant and a dielectric charge. The invention relates also to a pad used in field of high field and/or very high field magnetic resonance imaging made of at least such a material.

First claim

The invention claimed is:

1. A Material for use in a pad for at least one selected from the group consisting of high field and very high field magnetic resonance imaging instruments, wherein the material comprises:
at least one polar solvent having a melting point in a range of from 14° C. to 50° C.,
a dispersant, and
a dielectric charge component,

wherein the dielectric charge component is dispersed in a viscous matrix comprising the at least one polar solvent and the dispersant.

2. The material according to claim 1 wherein the polar solvent is selected from the group consisting of fluoro-ethylene carbonate, diethyl-cyano-ethyl phosphonate, ethyl-1-methyl-sulfone, tetramethylene sulfone, isopropyl-methyl-sulfone, and combination of two or more thereof.

3. The material according to claim 2 , wherein the dispersant is selected from the group consisting of gums, agaroses, gelatins, glycerols, celluloses, polyacrylamides, polysaccharides, polyacrylic polymers, polyethylene glycols, and combinations of two or more thereof.

4. The material according to claim 2 , wherein the dielectric charge component is SiC, BaTiO 3 or CaTiO 3 .

5. The material according to claim 2 , wherein the dielectric charge component is in a form of particles having average sizes in a range of from 0.1 μm to 50 μm.

6. The material according to claim 1 , wherein the dispersant is selected from the group consisting of gums, agaroses, gelatins, glycerols, celluloses, polyacrylamides, polysaccharides, polyacrylic polymers, polyethylene glycols, and combinations of two or more thereof.

7. The material according to claim 6 , wherein the dielectric charge component is in a form of particles having average sizes in a range of from 0.1 μm to 50 μm.

8. The material according to claim 1 , wherein the dielectric charge component is SiC, BaTiO 3 or CaTiO 3 .

9. The material according to claim 1 , wherein the dielectric charge component is in a form of particles having average sizes in a range of from 0.1 μm to 50 μm.

10. The material according to claim 9 , wherein the dielectric charge component is in a form of particles having average sizes in a range of from 7 μm to 8 μm.

11. The material according to claim 10 , wherein the dielectric charge component is SiC, BaTiO 3 or CaTiO 3 .

12. The material according to claim 1 , wherein a proportion of polar solvent is in a range of from 1% to 95% in a total volume of the material.

13. The material according to claim 12 , wherein the proportion of polar solvent is in a range of from 10% to 85% in the total volume of the material.

14. The material according to claim 1 , wherein the material comprises up to 40% of dispersant in a total volume of the material.

15. The material according to claim 14 , wherein a proportion of dispersant is in a range of from 0.5% to 9% in the total volume of the dispersant.

16. The material according to claim 1 , wherein a proportion of dielectric charge is in a range of from 4% to 90% in a total volume of the material.

17. The material according to claim 16 , wherein the proportion of dielectric charge is in a range of from 10% to 85% in the total volume of the material.

18. The material according to claim 1 , wherein a relative permittivity of the solvent is in a range of from 40 to 100.

19. The Pad used in at least one selected from the group consisting of high field and very high field magnetic resonance imaging, comprising the material according to claim 1 .

20. The material according to claim 1 , wherein a dielectric property of the material is stable over 1 month.

21. The material according to claim 1 , wherein a viscosity of the material is stable over 1 year.

Assignees

• Centre Nat Rech Scient
• Commissariat Energie Atomique
• Ecole Centrale Marseille
• Univ Daix Marseille Amu

Inventors

• Redha Abdeddaim
• Adenot-Engelvin Anne-Lise
• Dubois Marc
• Enoch Stefan
• Mallejac Nicolas
• Raolison Zo
• Sabouroux Pierre
• Vignaud Alexandre

Classifications

• G01R33/5659 Primary

  caused by a distortion of the RF magnetic field, e.g. spatial inhomogeneities of the RF magnetic field (G01R33/56509, G01R33/56518, G01R33/56536 take precedence) · CPC title

• G01R33/288 Primary

  Provisions within MR facilities for enhancing safety during MR, e.g. reduction of the specific absorption rate [SAR], detection of ferromagnetic objects in the scanner room · CPC title