Multilayer Spherical Composite Particles for Photoprotection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing photoprotective compositions fail to provide effective protection against both UVA and UVB radiation while maintaining good cosmetic properties such as stability, non-greasy feel, and easy spreading, especially on already pigmented skin without increasing melanin load or skin structure.
Innovation Solution
A composition comprising multilayer spherical composite particles with a core and two concentric layers of inorganic materials (silica and titanium dioxide) and a UV-screening agent, where the particles are present in less than 28% by weight, offering effective photoprotection and improved skin and hair care without the drawbacks of previous compositions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional photoprotective compositions use UV-screening agents and metal oxide pigments, then UV protection is provided, but cosmetic properties such as stability, non-greasy feel, and easy spreading deteriorate
Solution Approach 1:
The patent uses multilayer spherical composite particles comprising a core of material A (refractive index 1.3-1.8) covered by a layer of material B (refractive index 1.9-3.1, preferably titanium or zinc oxide) and an outer layer of material C (refractive index 1.3-1.8). This composite structure combines the UV-screening capability of metal oxides with the cosmetic benefits of spherical morphology and controlled refractive indices, achieving both effective photoprotection and improved cosmetic properties including stability, non-greasy feel, and easy spreading.
Solution Approach 2:
The patent applies different materials with specific refractive indices to different layers of the spherical particles. The core (material A) and outer layer (material C) have refractive indices of 1.3-1.8, while the intermediate layer (material B) has a higher refractive index of 1.9-3.1. This local differentiation of material properties optimizes both UV screening effectiveness and cosmetic performance, resolving the contradiction between protection and ease of application.
2Reliability
If photoprotective compositions aim to protect against both UVA and UVB radiation, then comprehensive photoprotection is achieved, but finding a suitable combination of UV-screening agents becomes extremely difficult
Solution Approach 1:
The multilayer spherical composite particles serve multiple functions simultaneously: the metal oxide layer (material B, preferably titanium or zinc oxide) provides UV-screening activity against both UVA and UVB radiation, while the spherical composite structure contributes to cosmetic properties including stability, non-greasy feel, and easy spreading. This multi-functionality reduces the need for complex combinations of separate UV-screening agents.
Solution Approach 2:
The composite particle structure integrates UV-screening metal oxides with spherical carrier materials having controlled refractive indices. This composite approach consolidates multiple functions (UVB screening, UVA screening, stability, cosmetic feel) into a single ingredient system, simplifying the overall composition while maintaining comprehensive photoprotection.
3Ease of operation
If spherical composite particles are used to improve cosmetic properties, then stability and spreading are enhanced, but effective photoprotection against both UVA and UVB becomes difficult to achieve
Solution Approach 1:
The patent creates multilayer spherical composite particles where the metal oxide layer (material B) provides UV-screening functionality while the spherical morphology and refractive index matching materials (A and C) provide cosmetic benefits. This composite design ensures that cosmetic properties and photoprotection effectiveness are achieved simultaneously rather than traded off against each other.
Solution Approach 2:
Different regions of the spherical particle have different properties: the core and outer layer (materials A and C) are optimized for cosmetic properties including refractive index matching and spherical morphology, while the intermediate metal oxide layer (material B) is optimized for UV-screening activity. This local quality differentiation resolves the contradiction between cosmetic performance and photoprotection effectiveness.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The composition provides homogeneous photoprotection, prevents skin darkening, improves skin color and uniformity, and maintains mechanical elasticity, ensuring effective UVB and UVA protection with enhanced cosmetic properties like non-greasy feel and stability.
Implementation Method 1
at least multilayer spherical composite particles comprising i) a core comprising at least one material A having a refractive index ranging from 1.3 to 1.8; and ii) at least one layer covering said core, comprising at least one material B having a refractive index ranging from 1.9 to 3.1; and iii) at least one second layer covering the material B, comprising at least one material C having a refractive index ranging from 1.3 to 1.8
Implementation Method 2
materials A, B and C being inorganic, and the inorganic materials A and C are chosen from the group formed by glass, silica, calcium carbonate and aluminium oxide, and mixtures thereof; the inorganic material B is chosen from metal oxides, preferably chosen from titanium, zinc, iron and zirconium oxides, and mixtures thereof
Implementation Method 3
b) at least one UV-screening agent
Data Source
AI summary
A subject matter of the present invention is a composition comprising: a) at least multilayer spherical composite particles comprising i) a core comprising at least one material A having a refractive index ranging from 1.3 to 1.8; and ii) at least one layer covering said core, comprising at least one material B having a refractive index ranging from 1.9 to 3.1; and iii) optionally at least one second layer covering the material B, comprising at least one material C having a refractive index ranging from 1.3 to 1.8; said composite particles being present in an amount less than 28.0% by weight relative to the total weight of the composition; and b) at least one UV-screening agent. This composition is for topical use and is more particularly intended for the photoprotection of the skin and/or hair against ultraviolet (UV) radiation.