Particulate metal oxide
AssigneeCroda International PLC
InventorsGraham Dransfield, Susan Cutter, Phillip Lyth
Life of this patent
Estimating the term…
Abstract
A particulate metal oxide having the mean length of the primary particles in the range from 50 to 90 nm, the mean width of the primary particles in the range from 5 to 20 nm, and the median volume particle diameter of the secondary particles is less than 45 nm. The metal oxide can be used in a sunscreen product that exhibits both effective UV protection and improved transparency.
Claims23
A particulate metal oxide wherein the mean length of the primary particles is in the range from 50 to 90 nm, the mean width of the primary particles is in the range from 5 to 20 nm, and the median particle volume diameter of the secondary particles is less than 45 nm.
A dispersion comprising particles of metal oxide in a dispersing medium wherein the mean length of the primary particles is in the range from 50 to 90 nm, the mean width of the primary particles is in the range from 5 to 20 nm, and the median particle volume diameter of the secondary particles is less than 45 nm.
A particulate metal oxide wherein the mean length of the primary particles is in the range from 55 to 85 nm, the mean width of the primary particles is in the range from 8 to 19 nm, and at least 70% of the primary particles have a length in the range from 55 to 85 nm.
A particulate metal oxide, optionally hydrophobic, having an extinction coefficient at 524 nm (E524) in the range from 0.2 to 0.7 l/g/cm, an extinction coefficient at 450 nm (E450) in the range from 0.5 to 1.5 l/g/cm, an extinction coefficient at 360 nm (E360) in the range from 5 to 8 l/g/cm, an extinction coefficient at 308 nm (E308) in the range from 40 to 60l/g/cm, a maximum extinction coefficient E(max) in the range from 45 to 75 l/g/cm, and a λ(max) in the range from 260 to 290 nm.
Dependencies are inferred from the claim text.