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The disclosure describes methods for producing bulk, particulate material that includes solid, generally ellipsoidal particles. Irregularly shaped feed particles with average particle sizes of up to 25 microns on a volume basis are dispersed in at least a portion of a combustible gas mixture by application of force and/or fluidizing agents. The combustible mixture with particles in suspension is then delivered, while controlling agglomeration or re-agglomeration of the particles, to at least one flame front. There, the mixture and suspended particles are uniformly distributed across the surface(s) of and passed through the flame front(s) with a high concentration of particles in the mixture. This flame front and the resultant flame(s) with suspended particles are located in at least one "wall free" zone. In such zone(s) the flame(s) may expand while the particles are maintained in dispersion and heated, with controlled and highly efficient application of heating energy. At least...

InventeurRichard B. Castle
Cessionnaire d'origineMinnesota Mining and Manufacturing Company
Classification américaine actuelle428/325; 428/331; 428/332; 428/402; 428/404; 428/407; 524/492; 524/493; 524/494
Classification internationale: B32B 516

Afficher le brevet sur l'USPTO
Rechercher dans la base de données de l'USPTO

Citations

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Revendications

1. A composition of matter comprising solid particles wherein:

A. at least a portion of said solid particles are generally ellipsoidal particles that are substantially glassy;
B. at least a portion of said solid particles respectively
constitute product particles produced by at least partial fusion of feed particles while they are flowing in suspension in hot combustion gases, said feed particles containing volatile material ranging in amount from about 1 to about 25% by weight based on the weight of the feed particles,
are derived from, and have chemical compositions corresponding substantially with the chemical composition of, one or more silicas and/or silicates present in naturally occurring mineral deposits, except that the amount of volatile material in the product particles may differ from the volatile content of the corresponding naturally occurring mineral,
have a Color Quest 457 nanometer brightness of at least about 60,
have an average particle size by volume in the range of up to about 15 microns, and
include at least about 1% of void volume, based on the volume of the product particles; and
C. said composition of matter comprises about 15 to 100% by volume of said generally ellipsoidal particles that have said chemical compositions, based on the total volume of solid particles present in said composition of matter.

2. A composition of matter according to claim 1 comprising at least 50% by volume of generally ellipsoidal or substantially spherical particles.

3. A composition of matter according to claim 1 comprising about 75 to 100% by volume of generally ellipsoidal or substantially spherical particles.

4. A composition of matter according to claim 1 comprising about 15% to 90% by volume of said generally ellipsoidal particles.

5. A composition of matter according to claim 1 comprising about 15% to 95% by volume of said generally ellipsoidal particles.

6. A composition of matter according to claim 1 comprising about 15% to 99% by volume of said generally ellipsoidal particles.

7. A composition of matter according to claim 1 consisting of said generally ellipsoidal particles.

8. A composition of matter according to claim 1 consisting of said generally ellipsoidal or substantially spherical particles.

9. A composition of matter according to claim 1 wherein at least a portion of said solid particles has a chemical composition corresponding substantially with that of at least one silica.

10. A composition of matter according to claim 1 wherein at least a portion of said solid particles has a chemical composition corresponding substantially with that of a known, naturally occurring mineral species which contains calcium silicate (s).

11. A composition of matter according to claim 1 wherein at least a portion of said solid particles has a chemical composition corresponding substantially with that of known, naturally occurring species which contains one or more silicates selected from the group consisting of calcium silicate(s), sodium silicates, potassium silicates, lithium silicates, volcanic ashes and other materials of volcanic origin.

12. A composition of matter according to claim 1 wherein said composition of matter is derived from feed material in which the volatile material is chemically bound to the feed particles.

13. A composition of matter according to claim 1 wherein at least a portion of said feed particles has been dried prior to combustion.

14. A composition of matter according to claim 1 wherein said composition of matter is derived from feed particles which have been treated to add volatile material.

15. A composition of matter according to claim 1 wherein said composition of matter is derived from feed particles to which volatile material has been added prior to the fusion step by dissolving and precipitating said silica(s) and/or silicate(s).

16. A composition of matter according to claim 1 wherein said composition of matter is derived from feed particles which have been treated prior to the fusion step to reduce their content of volatile material.

17. A composition of matter according to claim 1 wherein said composition of matter is derived from feed particles which have not been treated to add volatile material.

18. A composition of matter according to claim 1 wherein said composition of matter is derived from silica(s) and/or silicate(s) which have remained solids from the time of their extraction from the earth until their suspension in said hot combustion gases.

19. A composition of matter according to claim 1 wherein the amount of volatile material in the product is less than the amount of volatile material in the corresponding naturally occurring mineral and/or in said feed material.

20. A composition of matter according to claim 1 wherein the silicate and/or silicates present in the naturally occurring mineral deposits contain(s) at least 1 percent by weight of volatile material[s].

21. A composition of matter according to claim 1 wherein the silicate and/or silicates present in the naturally occurring mineral deposits contain(s) at least 2 percent by weight of volatile material[s].

22. A composition of matter according to claim 1 wherein the silicate and/or silicates present in the naturally occurring mineral deposits contain(s) up to about 7 percent by weight of volatile materials[s].

23. A composition of matter according to claim 1 wherein the silicate and/or silicates present in the naturally occurring mineral deposits contain(s) up to about 10 percent by weight of volatile material[s].

24. A composition of matter according to claim 1 wherein the silicate and/or silicates present in the naturally occurring mineral deposits contain(s) up to about 25 percent by weight of volatile materials[s].

25. A composition of matter according to claim 1 wherein said solid particles have a carbon content of up to about 0.2% by weight, based on the total weight of the solid particles.

26. A composition of matter according to claim 1 wherein said solid particles have a carbon content of up to about 0.15% by weight based on the total weight of the solid particles.

27. A composition of matter according to claim 1 wherein said solid particles have a carbon content of up to about 0.1% by weight based on the total weight of the solid particles.

28. A composition of matter according to claim 1 wherein said solid particles contain small amounts of highly colored iron-containing minerals.

29. A composition of matter according to claim 1 wherein said solid particles contain small amounts of any material selected from the group consisting of Fe.sub.2 O.sub.3, Fe.sub.3 O.sub.4 FeO, manganese and mixtures of these.

30. A composition of matter according to claim 29 wherein said solid particles comprise up to about 0.2% by weight of any of said materials.

31. A composition of matter according to claim 29 wherein said solid particles comprise up to about 0.1% by weight of any of said materials.

32. A composition of matter according to claim 29 wherein said solid particles comprise up to about 0.05% by weight of any of said materials.

33. A composition of matter according to claim 29 wherein said solid particles comprise up to about 5% by weight of FeO.

34. A composition of matter according to claim 29 wherein said solid particles comprise up to about 2% by weight of FeO.

35. A composition of matter according to claim 29 wherein said solid particles comprise up to about 1% by weight of FeO.

36. A composition of matter according to claim 1 wherein said solid particles are amorphous.

37. A composition of matter according to claim 1 wherein said solid particles are partially crystalline.

38. A composition of matter according to claim 37 wherein said solid particles are up to about 90% crystalline.

39. A composition of matter according to claim 37 wherein said solid particles are about 0.1 to about 75% crystalline.

40. A composition of matter according to claim 37 wherein said solid particles are about 5 to about 60% crystalline.

41. A composition of matter according to claim 1 wherein said generally ellipsoidal particles have an average particle size by volume in the range of up to about 10 microns.

42. A composition of matter according to claim 1 wherein said generally ellipsoidal particles have an average particle size by volume in the range of up to about 8 microns.

43. A composition of matter according to claim 1 wherein said generally ellipsoidal particles have an average particle size by volume in the range of up to about 6 microns.

44. A composition of matter according to claim 1 wherein the specific gravities of the generally ellipsoidal particles differ from the specific gravities of the feed particles.

45. A composition of matter according to claim 1 wherein the specific gravities of the generally ellipsoidal particles are lower than the specific gravities of the feed particles.

46. A composition of matter according to claim 45 wherein said specific gravities of the generally ellipsoidal particles are in the range of about 1 to about 15% lower than the specific gravities of the feed particles.

47. A composition of matter according to claim 45 wherein said specific gravities of the generally ellipsoidal particles are in the range of about 1 to about 10% lower than the specific gravities of the feed particles.

48. A composition of matter according to claim 1 wherein the void volume is in the range of about 1 to about 20 volume percent.

49. A composition of matter according to claim 1 wherein the void volume is at least about 3 percent.

50. A composition of matter according to claim 1 wherein the void volume is at least about 5 percent.

51. A composition of matter according to claim 1 wherein the void volume is up to about 12 percent.

52. A composition of matter according to claim 1 wherein the void volume is up to about 15 percent.

53. A composition of matter according to claim 1 wherein the void volume is up to about 20 percent.

54. A composition of matter according to claim 1 wherein the product particles have a Color Quest 457 nanometer brightness of at least about 70.

55. A composition of matter according to claim 1 wherein the product particles have a Color Quest 457 nanometer brightness of at least about 80.

56. A composition of matter according to claim 1 wherein said composition comprises said solid particles and a polymeric material.

57. A composition of matter according to claim 56 wherein the volume of said solid particles, based on the total volume of such particles and polymeric material is in the range of about 0.05% to about 99.9%.

58. A composition of matter according to claim 56 wherein said polymeric material is a film.

59. A composition of matter according to claim 58 wherein said composition comprises about 0.05 to about 0.5% by volume of said solid particles.

60. A method for reducing friction of a material, which comprises applying a composition of matter according to claim 56.

61. A composition of matter according to claim 1 wherein said composition comprises said solid particles in a curable liquid composition.

62. A composition of matter according to claim 1 wherein said composition comprises said solid particles in a curable solid composition.

63. A composition of matter according to claim 61 or 62 wherein said curable composition is UV curable.

64. A composition of matter according to claim 1 wherein said composition is a liquid coating composition which comprises said solid particles.

65. A composition of matter according to claim 64 wherein said composition comprises 5 to 50% based on the total volume of the composition as a whole.

66. A composition of matter according to claim 1 wherein said composition comprises said solid particles and a metallic material.

67. A composition of matter according to claim 1 wherein said composition comprises said solid particles and an inorganic cement forming component.

68. A composition of matter according to claim 1 wherein said composition is a caulk.

69. A composition of matter according to claim 1 wherein said composition is a cement.

70. A composition of matter according to claim 1 wherein said composition is an adhesive.

71. A composition of matter according to claim 1 wherein said composition is a smooth-textured fluent or spreadable material.

72. A composition according to claim 71 wherein said solid particles are dispersed in a pharmacologically acceptable carrier.

73. A composition of matter according to claim 1 wherein said composition is a smooth-surfaced web.

74. A composition of matter according to claim 73 wherein said generally ellipsoidal particles have an average particle size of about 10 microns.

75. A composition of matter according to claim 1 wherein said generally ellipsoidal particles of said composition of matter adhere to one another.

76. A composition of matter according to claim 75 wherein said composition has a shaped form.

77. A method for treating skin, which comprises applying a composition of matter that contains the solid particles of claim 1.

78. A method for improving the resistance of surfaces to abrasion, which comprises applying a composition of matter that contains the solid particles of claim 1.

79. A method for improving the resistance of surfaces to stains, which comprises applying a composition of matter that contains the solid particles of claim 1.

80. A method for reducing friction of a material, which comprises applying a composition of matter that contains the solid particles of claim 1.

81. A composition of matter containing solid particles according to claim 1 which is useful for application to body parts of humans or animals.

82. A composition of matter according to claim 81, wherein about 90 to 100% by volume of the solid particles have diameters, on average, in the range of up to 10 microns.

83. A composition of matter according to claim 81 wherein about 90 to 100% by volume of the solid particles are generally ellipsoidal or substantially spherical.

84. A pharmaceutical or cosmetic preparation containing solid particles according to claim 81, in the form of a fluent or spreadable material.

85. A composition of matter comprising solid particles wherein:

A. at least a portion of said solid particles are generally ellipsoidal particles that are substantially glassy;
B. at least a portion of said solid particles respectively
constitute product particles produced by at least partial fusion of feed particles while they are flowing in suspension in hot combustion gases, said feed particles containing volatile material ranging in amount from about 1 to about 25% by weight based on the weight of the feed particles,
are derived from, and have chemical compositions corresponding substantially with the chemical composition of, one or more silicas present in naturally occurring mineral deposits, except that the amount of volatile material in the product particles may differ from the volatile content of the corresponding naturally occurring mineral,
have a Color Quest 457 nanometer brightness of at least about 60,
have an average particle size by volume in the range of up to about 15 microns, and
include at least about 1% of void volume, based on the volume of the product particles; and
C. said composition of matter comprises about 15 to 100% by volume of said generally ellipsoidal particles that have said chemical compositions, based on the total volume of solid particles present in said composition of matter.

86. A composition of matter comprising solid particles wherein:

A. at least a portion of said solid particles are generally ellipsoidal particles that are substantially glassy;
B. at least a portion of said solid particles respectively
constitute product particles produced by at least partial fusion of feed particles while they are flowing in suspension in hot combustion gases, said feed particles containing volatile material ranging in amount from about 1 to about 25% by weight based on the weight of the feed particles,
are derived from, and have chemical compositions corresponding substantially with the chemical composition of, one or more silicates present in naturally occurring mineral deposits, except that the amount of volatile material in the product particles may differ from the volatile content of the corresponding naturally occurring mineral,
have a Color Quest 457 nanometer brightness of at least about 60,
have an average particle size by volume in the range of up to about 15 microns, and
include at least about 1% of void volume, based on the volume of the product particles; and
C. said composition of matter comprises about 15 to 100% by volume of said generally ellipsoidal particles that have said chemical compositions, based on the total volume of solid particles present in said composition of matter.

87. A composition of matter comprising solid particles wherein:

A. at least a portion of said solid particles are generally ellipsoidal particles that are substantially glassy;
B. at least a portion of said solid particles respectively
constitute product particles produced by at least partial fusion of feed particles while they are flowing in suspension in hot combustion gases, said feed particles containing volatile material ranging in amount from about 2 to about 25% by weight based on the weight of the feed particles,
are derived from, and have chemical compositions corresponding substantially with the chemical composition of, one or more silicas and/or silicates present in naturally occurring mineral deposits, except that the amount of volatile material in the product particles may differ from the volatile content of the corresponding naturally occurring mineral,
have a Color Quest 457 nanometer brightness of at least about 60,
have an average particle size by volume in the range of up to about 10 microns, and
include from about 1% to about 20% of void volume, based on the volume of the product particles; and
C. said composition of matter comprises about 50 to 100% by volume of said generally ellipsoidal particles that have said chemical compositions, based on the total volume of solid particles present in said composition of matter.

88. A composition of matter comprising solid particles wherein:

A. at least a portion of said solid particles are generally ellipsoidal particles that are substantially glassy;
B. at least a portion of said solid particles respectively
constitute product particles produced by at least partial fusion of feed particles while they are flowing in suspension in hot combustion gases, said feed particles containing volatile material ranging in amount from about 2 to about 25% by weight based on the weight of the feed particles,
are derived from, and have chemical compositions corresponding substantially with the chemical composition of, one or more silicas and/or silicates present in naturally occurring mineral deposits, except that the amount of volatile material in the product particles may differ from the volatile content of the corresponding naturally occurring mineral,
have a Color Quest 457 nanometer brightness of at least about 60,
have an average particle size by volume in the range of up to about 8 microns, and include about 1 to about 15% of void volume, based on the volume of the product particles; and
C. said composition of matter comprises about 60 to 100% by volume of said generally ellipsoidal particles that have said chemical compositions, based on the total volume of solid particles present in said composition of matter.

89. A composition of matter comprising solid particles wherein:

A. at least a portion of said solid particles are generally ellipsoidal particles that are substantially glassy;
B. at least a portion of said solid particles respectively
constitute product particles produced by at least partial fusion of feed particles while they are flowing in suspension in hot combustion gases, said feed particles containing volatile material ranging in amount from about 2 to about 25% by weight based on the weight of the feed particles,
are derived from, and have chemical compositions corresponding substantially with the chemical composition of, one or more silicas and/or silicates present in naturally occurring mineral deposits, except that the amount of volatile material in the product particles may differ from the volatile content of the corresponding naturally occurring mineral,
have a Color Quest 457 nanometer brightness of at least about 60,
have an average particle size by volume in the range of up to about 6 microns, and
include about 1 to about 10% of void volume, based on the volume of the product particles; and
C. said composition of matter comprises about 75 to 100% by volume of said generally ellipsoidal particles that have said chemical compositions, based on the total volume of solid particles present in said composition of matter.