Spherical boron nitride particles and method for preparing them
First Claim
1. A method for producing crystalline or partially crystalline particles of boron nitride (BN), comprising the steps of:
- (a) generating an aerosol comprising precursor particles of boron nitride (BN) suspended in an aerosol gas;
(b) generating a plasma from a plasma gas, the plasma comprising nitrogen atoms, the plasma including a plasma hot zone having a temperature sufficiently high to melt boron nitride;
(c) directing the aerosol into the plasma hot zone and allowing the precursor particles of boron nitride to melt; and
(d) allowing the molten particles to exit the hot zone, whereby they cool and solidify to form crystalline or partially crystalline product particles of boron nitride.
6 Assignments
0 Petitions
Accused Products
Abstract
Spherical and polyhedral particles of boron nitride and method of preparing them. Spherical and polyhedral particles of boron nitride are produced from precursor particles of hexagonal phase boron nitride suspended in an aerosol gas. The aerosol is directed to a microwave plasma torch. The torch generates plasma at atmospheric pressure that includes nitrogen atoms. The presence of nitrogen atoms is critical in allowing boron nitride to melt at atmospheric pressure while avoiding or at least minimizing decomposition. The plasma includes a plasma hot zone, which is a portion of the plasma that has a temperature sufficiently high to melt hexagonal phase boron nitride. In the hot zone, the precursor particles melt to form molten particles that acquire spherical and polyhedral shapes. These molten particles exit the hot zone, cool, and solidify to form solid particles of boron nitride with spherical and polyhedral shapes. The molten particles can also collide and join to form larger molten particles that lead to larger spherical and polyhedral particles.
-
Citations
85 Claims
-
1. A method for producing crystalline or partially crystalline particles of boron nitride (BN), comprising the steps of:
-
(a) generating an aerosol comprising precursor particles of boron nitride (BN) suspended in an aerosol gas;
(b) generating a plasma from a plasma gas, the plasma comprising nitrogen atoms, the plasma including a plasma hot zone having a temperature sufficiently high to melt boron nitride;
(c) directing the aerosol into the plasma hot zone and allowing the precursor particles of boron nitride to melt; and
(d) allowing the molten particles to exit the hot zone, whereby they cool and solidify to form crystalline or partially crystalline product particles of boron nitride. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
-
-
18. A method for generating larger particles of boron nitride from smaller particles of boron nitride, comprising the steps of:
-
(a) generating an aerosol comprising precursor particles of boron nitride suspended in an aerosol gas;
(b) generating a plasma from a plasma gas, the plasma comprising nitrogen atoms, the plasma including a plasma hot zone having a temperature sufficiently high to melt boron nitride;
(c) directing the aerosol into the plasma hot zone and allowing the precursor particles of boron nitride to melt, collide, and join to form larger particles; and
(d) allowing the molten particles to exit the hot zone, whereby they cool and solidify to form solid particles of boron nitride that are larger than the precursor particles. - View Dependent Claims (19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35)
-
-
36. A method for melting boron nitride (BN), comprising the steps of:
-
(a) generating a plasma comprising nitrogen atoms, the plasma including a plasma hot zone having a temperature sufficiently high to melt hexagonal phase boron nitride; and
(b) exposing precursor particles of boron nitride (BN) to the plasma, whereby boron nitride melts. - View Dependent Claims (37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50)
-
-
51. Crystalline or partially crystalline boron nitride (BN) particles made by the process comprising the steps of:
-
(a) generating an aerosol comprising precursor particles of boron nitride (BN) suspended in an aerosol gas;
(b) generating a plasma from a plasma gas, the plasma comprising nitrogen atoms, the plasma including a plasma hot zone having a temperature sufficiently high to melt boron nitride;
(c) directing the directing the aerosol into the plasma hot zone and allowing the precursor particles of boron nitride to melt; and
(d) allowing the molten particles to exit the hot zone, whereby they cool and solidify to form crystalline or partially crystalline solid particles of boron nitride. - View Dependent Claims (52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67)
-
-
68. Crystalline or partially crystalline boron nitride particles made by the method comprising the steps of:
-
(a) generating an aerosol comprising precursor particles of boron nitride suspended in an aerosol gas;
(b) generating a plasma from a plasma gas, the plasma comprising nitrogen atoms, the plasma including a plasma hot zone having a temperature sufficiently high to melt boron nitride but not high enough to decompose the boron nitride;
(c) directing the aerosol into the plasma hot zone and allowing the precursor particles of boron nitride to melt, collide, and join to form larger particles; and
(d) allowing the molten particles to exit the hot zone, whereby they cool and solidify to form crystalline or partially crystalline solid particles of boron nitride that are larger than the precursor particles. - View Dependent Claims (69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85)
-
Specification