Photoprotective composition and screening agents for said composition
AssigneeL'oreal
InventorDidier Candau
Life of this patent
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Abstract
The present invention concerns a photoprotective composition comprising at least one interferential screening agent screening UVA and/or UVB.
Claims37
A photoprotective composition comprising at least one interferential screening agent screening UVA and/or UVB, said screening agent comprising a diffracting structure comprising at least one diffraction grating that has a periodicity of 270 nm or less and does not diffract the light in the visible region, the structure of the grating being etched either into the bulk of a material or into a material deposited on an organic or mineral substrate of spherical or lamellar form, the interferential screening agent being selected so that the composition has a transmission factor of 80% or more over an interval at least 200 nm wide in the 400-800 nm range.
An interferential screening agent comprising a diffracting interferential structure comprising at least one diffraction grating that does not diffract the light in the visible region, said diffracting interferential structure arranged so that the screening agent has:
- a transmission factor of 80% or less for at least one wavelength in the 290-400 nm range;
- and
- a transmission factor of 80% or more, over at least one interval of at least 200 nm wide in the 400-800 nm range,
- the interferential structure comprising at least one diffraction grating having a periodicity of 270 nm or less, the structure of the grating being etched either into the bulk of a material or into a material deposited on an organic or mineral substrate of spherical or lamellar form.
A method to increase a sun protective factor of a cosmetic or dermatological composition comprising introducing in the composition at least one diffracting interferential screening agent, which screens UVA and/or UVB,
- said screening agent comprising at least one diffraction grating that has a periodicity of 270 nm or less and does not diffract the light in the visible region, the structure of the grating being etched either into the bulk of a material or after depositing a material on an organic or mineral substrate of spherical or lamellar form, the interferential screening agent being selected so that the composition has a transmission factor of 80% or more over an interval at least 200 nm wide in the 400-800 nm range.
Dependencies are inferred from the claim text.