Oral care article comprising a hydrophobic delivery carrier and solid hydrophilic particle comprising a bleaching agent
An oral care article in form of a strip for use in the oral cavity. The oral care article includes a hydrophobic delivery carrier comprising embedded solid hydrophilic particles comprising at least one bleaching agent, wherein at least about 20 parts by weight of the particles dissolve in about 100 parts by weight of water and/or the particles increase in volume and/or weight by at least about 50% upon contact with water.
1. An oral care article comprising:
a) a solid hydrophobic delivery carrier in form of a strip having a length and a width forming a first surface and having a thickness extending from the first surface to a second surface, wherein an average thickness of the strip is less than about 3 mm; and
b) solid hydrophilic particles comprising a bleaching agent, wherein the solid hydrophilic particles release the bleaching agent upon contact with water,
wherein the solid hydrophilic particles are disposed in and embedded in the solid hydrophobic delivery carrier, wherein the solid hydrophilic particles are disposed i) at least partially below the first surface, and ii) at least partially at or above the first surface of the solid hydrophobic delivery carrier;
wherein at least about 20 parts by weight of the solid hydrophilic particles dissolve in about 100 parts by weight of water and/or the solid hydrophilic particles increase in volume and/or weight by at least about 50% upon contact with water.
2. The oral care article of claim 1 , wherein more than about 50% of the volume of the solid hydrophilic particles is disposed below or at the first surface of the hydrophobic delivery carrier.
3. The oral care article of claim 1 , wherein more than about 10% of a surface area of the solid hydrophilic particles is disposed at the first surface of the hydrophobic delivery carrier and exposed to an external environment surrounding the hydrophobic delivery carrier.
4. The oral care article of claim 1 , wherein a number-average equivalent-diameter or a volume-average equivalent-diameter of the solid hydrophilic particles is in a range of from about 1 micron to about 1000 microns.
5. The oral care article of claim 1 , wherein a ratio of the average thickness of the hydrophobic delivery carrier and/or the article divided by a number-average equivalent-diameter or a volume-average equivalent-diameter of the solid hydrophilic particles is from about 0.01 to about 100.
6. The oral care article of claim 1 , wherein the average thickness of the hydrophobic delivery carrier or article is in a range of from about 0.01 mm to about 3 mm.
7. The oral care article of claim 1 , wherein an average length of the hydrophobic delivery carrier is in a range of from about 35 mm to about 100 mm.
8. The oral care article of claim 1 , wherein an average width of the hydrophobic delivery carrier is in a range of from about 3 mm to about 30 mm.
9. The oral care article of claim 1 , wherein the hydrophobic delivery carrier is shaped in a form of a dental arch.
10. The oral care article of claim 1 , wherein the article is a unit-dose article and/or a removable article.
11. The oral care article of claim 1 , wherein the article and/or the hydrophobic delivery carrier is a single layer.
12. The oral care article of claim 1 , wherein a concentration of the bleaching agent at the first surface is greater than a concentration of the bleaching agent at the second surface.
13. The oral care article of claim 12 , wherein the concentration of the bleaching agent at the first surface is from about 1 microgram/cm 2 to about 10000 micrograms/cm 2 .
14. The oral care article of claim 12 , wherein the concentration of the bleaching agent at the first surface is from about 10 micrograms/cm 2 to about 5000 micrograms/cm 2 .
15. The oral care article of claim 1 , wherein the concentration of the bleaching agent at the second surface is from about 0.001 micrograms/cm 2 to about 500 micrograms/cm 2 .
16. The oral care article of claim 1 , wherein a ratio of the concentration of the bleaching agent at the first surface divided by the concentration of the bleaching agent at the second surface is greater than 1.
17. The oral care article according to claim 1 , wherein an overall concentration of bleaching agent is from about 0.01% to about 10%, by weight of the article.
18. The oral care article according to claim 1 , wherein an overall concentration of bleaching agent is from about 0.1% to about 3%, by weight of the article.
19. The oral care article of claim 1 , wherein the solid hydrophilic particles comprise from about 10% to about 50%, by weight of the solid hydrophilic particles, of bleaching agent.
20. The oral care article of claim 1 , wherein the bleaching agent comprises peroxide.
21. The oral care article of claim 20 , wherein the bleaching agent comprises: (i) a complex of hydrogen peroxide and polyvinylpyrrolidone (PVP) polymer, (ii) urea peroxide, or (iii) combinations thereof.
22. The oral care article of claim 1 , wherein the hydrophobic delivery carrier comprises a material having: (i) a needle consistency value of from about 0.1 to about 100 as measured by ASTM D1321-16a; and/or (ii) a cone penetration consistency value of less than about 10 as measured by ASTM D937-07; and/or (iii) a drop melting point of from about 60° C. to about 120° C. as measured by ASTM D127-08; and/or (iv) a flexural stiffness of greater than about 50 g/cm as measured by ASTM D2923-95.
23. The oral care article of claim 22 , wherein the hydrophobic delivery carrier comprises a material having: (i) a needle consistency value of from about 1 to about 10 as measured by ASTM D1321-16a; and/or (ii) a cone penetration consistency value of less than about 5 as measured by ASTM D937-07; and/or (iii) a drop melting point of from about 80° C. to about 100° C. as measured by ASTM D127-08; and/or (iv) a flexural stiffness of from about 200 g/cm to about 500 g/cm as measured by ASTM D2923-95.
24. The oral care article of claim 1 , wherein the hydrophobic delivery carrier comprises a wax, a polymer, or a combination thereof.
25. The oral care article of claim 1 , wherein the hydrophobic delivery carrier comprises microcrystalline wax and/or polyethylene polymer.
26. A kit comprising the oral care article of claim 1 and an electromagnetic radiation source capable of directing electromagnetic radiation with one or more wavelengths in the range of from about 200 nm to about 1700 nm towards at least one tooth, wherein the electromagnetic radiation impinges on the outer surface of the hydrophobic delivery carrier in the range of from about 175 mW/cm 2 to about 225 mW/cm 2 .
27. A method for whitening teeth comprising the steps of:
a) applying the oral care article of claim 1 to at least one tooth surface such that the first surface of the article contacts the at least one tooth surface;
b) letting the article stay on the at least one tooth surface for at least 1 minute; and
c) optionally applying electromagnetic radiation for at least 1 minute.