What is claimed is:
1. A perfuming or flavoring microcapsule comprising at least one perfuming or flavoring ingredient dispersed in or adsorbed within a polymeric carrier material, wherein the microcapsule further comprises an effective amount of a fireproofing agent susceptible of reducing the dust hazard explosive class of the microcapsule to an St-1 classification.
2. The perfuming or flavoring microcapsule according to claim 1, wherein the fireproofing agent is selected from the group consisting of sodium silicate, potassium silicate, sodium carbonate, sodium hydrogen carbonate, monoammonium phosphate or carbonate, diammonium phosphate, mono-, di- or trisodium phosphate, sodium hypophosphite, melamine cyanurate, chlorinated hydrocarbons and mixtures thereof.
3. The perfuming or flavoring microcapsule according to claim 1, which comprises from 5 to 90% by weight of fireproofing agent relative to the dry weight of the microcapsule.
4. The perfuming or flavoring microcapsule according to claim 3, which comprises from 5 to 15% by weight of fireproofing agent relative to the dry weight of the microcapsule.
5. The perfuming or flavoring microcapsule according to claim 1, which comprises from 1 to 80% by weight of perfume or flavor relative to the total weight of the microcapsule.
6. The perfuming or flavoring microcapsule according to claim 1, which comprises from 1 to 50% by weight of perfume or flavor relative to the total weight of the microcapsule.
7. A method for the preparation of perfuming or flavoring microcapsules, which comprises adding a fireproofing agent to an aqueous emulsion of the perfuming or flavoring ingredient in the carrier polymeric material, and spray-drying the obtained emulsion to form a powder comprising microcapsules of at least one perfuming or flavoring ingredient dispersed in or adsorbed within a polymeric carrier material and containing an effective amount of a fireproofing agent susceptible of reducing the dust hazard explosive class of the microcapsule to an St-1 classification.
8. The method of claim 7, which further comprises impregnating a porous polymeric carrier material with the perfuming or flavoring ingredient and coating the resulting system with a fireproofing agent.
9. The method of claim 7, which further comprises spray-drying an aqueous emulsion of a perfuming or flavoring ingredient in a polymeric carrier, and dry blending the spray-dried powder obtained with a fireproofing agent in a powdered form.
10. The method of claim 7 wherein the fireproofing agent is selected from the group consisting of sodium silicate, potassium silicate, sodium carbonate, sodium hydrogen carbonate, monoammonium phosphate or carbonate, diammonium phosphate, mono-, di- or trisodium phosphate, sodium hypophosphite, melamine cyanurate, chlorinated hydrocarbons and mixtures thereof.
11. A perfumed product selected from the group consisting of a perfume, a Cologne, an after-shave lotion, a soap, a bath or shower gel, a deodorant, a body lotion, a shampoo or another hair-care product, a detergent, a fabric softener, a household cleaner and a cleaning and deodorizing block for toilet tanks, which further comprises perfuming microcapsules according to claim 1.
12. A perfumed product selected from the group consisting of a perfume, a Cologne, an after-shave lotion, a soap, a bath or shower gel, a deodorant, a body lotion, a shampoo or another hair-care product, a detergent, a fabric softener, a household cleaner and a cleaning and deodorizing block for toilet tanks, which includes perfuming microcapsules made according to the method of claim 7.
13. A food, beverage or pharmaceutical product, which includes flavoring microcapsules according to claim 1.
14. A food, beverage or pharmaceutical product, which includes flavoring microcapsules made according to the method of claim 7.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1-20. (canceled)
21. An ohmic contact comprising:
a layer of p-type GaN-based material;
a layer of metal configured to provide a metal contact;
a first layer of p-type group II-VI compound semiconductor material comprising a first group VI element, the first layer located adjacent to the layer of p-type GaN-based material; and
a second layer of p-type group II-VI compound semiconductor material comprising a second group VI element different than the first group VI element, the second layer located adjacent to the layer of metal.
22. The ohmic contact of claim 21, further comprising:
a graded bandgap region of p-type group II-VI compound semiconductor material sandwiched between the first layer and the second layer, wherein the graded bandgap region of material comprises the first group VI element and the second group VI element.
23. The ohmic contact of claim 22, wherein:
the p-type GaN-based material is InxAlyGa1-x-yN;
the first layer comprises material having a general formula XY wherein X is an element selected from group II and Y is the first group VI element;
the second layer comprises material having a general formula XZ wherein X is the element selected from group II and Z is the second group VI element; and
the graded bandgap region of material has a general formula XYnZ1-n wherein X is an element selected from group II, Y is the first group VI element, and Z is the second group VI element.
24. The ohmic contact of claim 23, wherein the graded bandgap region contains one of a) a linearly graded region of semiconductor material and b) a non-linearly graded region of semiconductor material.
25. The ohmic contact of claim 23, wherein a first valence band offset between the second layer and the layer of metal is less than a second valence band offset between the layer of p-type GaN-based material and the layer of metal.
26. The ohmic contact of claim 25, wherein the first layer comprises a first one of a) ZnTe, b) ZnSe, and c) ZnO; and wherein the second layer comprises a second one of a) ZnTe, b) ZnSe, and c) ZnO, the first one being different than the second one.
27. An ohmic contact comprising:
a first layer of p-type InAlGaN;
a second layer of metal configured to provide a metal contact; and
a graded bandgap region of material sandwiched between the first layer and the second layer.
28. The ohmic contact of claim 27, wherein the graded bandgap region of material comprises GaxIn1-xNy (0\u2266x<1) and (0\u2266y<1).
29. The ohmic contact of claim 27, wherein the graded bandgap region of material comprises:
a first sub-region of InGaN located adjacent to the first layer;
a second sub-region of In located adjacent to the second layer; and
a third sub-region of InN located between the first sub-region and the second sub-region.
30. The ohmic contact of claim 29, wherein the metal of the second layer of metal is a metal other than Indium.
31. The ohmic contact of claim 29, wherein the metal of the second layer of metal is Indium.