Bright Pigment Coating with Hydroxyapatite for Spreadability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Cosmetic compositions containing conventional bright pigments suffer from poor spreadability, feel upon application, and biocompatibility due to their low oil adsorbability and instability, particularly when applied to the skin or keratinous materials like nails and hair.
Innovation Solution
A bright pigment with a scaly substrate coated by an outermost layer containing hydroxyapatite or hydrocalumite, an anionic pigment with an acidic group, and cerium or aluminum oxides, along with an interference color or silver-containing coating, enhancing oil adsorbability and biocompatibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If conventional bright pigments (aluminium powder, metal-coated glass particles, etc.) are used, then metallic luster and brightness are achieved, but oil adsorbability is poor resulting in inadequate spreadability and feel upon application
Solution Approach 1:
The invention uses composite particles consisting of a scaly substrate (glass or resin) coated with multiple layers including a metal oxide coating (titanium oxide, zirconium oxide, etc.) and an outermost coating containing amorphous calcium phosphate (5-50 mass%). This composite structure combines the metallic luster from the substrate and metal oxide layers with the oil adsorbability of amorphous calcium phosphate, achieving both brightness and spreadability.
Solution Approach 2:
The invention controls the amorphous calcium phosphate content within 5-50 mass% of the total particle mass to optimize both oil adsorbability and brightness. Additionally, the particle size is controlled within 1-10 μm diameter and 0.1-5 μm thickness, and the metal oxide coating thickness is controlled at 1-10 nm, creating optimal parameters for both aesthetic properties and application performance.
2Ease of operation
If amorphous calcium phosphate is used as the outermost coating to improve oil adsorbability, then spreadability and feel are enhanced, but water solubility increases causing instability
Solution Approach 1:
The invention structures the coating system as nested layers: the scaly substrate is coated with a metal oxide layer, which is in turn coated with the amorphous calcium phosphate outermost coating. This nested structure protects the amorphous calcium phosphate from direct environmental exposure while maintaining its oil adsorbability function, thereby improving stability.
Solution Approach 2:
The combination of metal oxide coating (providing stability and barrier properties) with amorphous calcium phosphate outermost coating (providing oil adsorbability) creates a composite structure where each layer compensates for the weaknesses of the other, achieving both stability and functionality.
3Ease of operation
If the amorphous calcium phosphate content is increased to enhance oil adsorbability, then spreadability improves, but coating stability deteriorates
Solution Approach 1:
The invention optimizes the amorphous calcium phosphate content within the specific range of 5-50 mass% of total particle mass. This parameter control ensures sufficient oil adsorbability for good spreadability while preventing excessive water solubility that would compromise coating stability. The lower limit (5 mass%) ensures adequate oil adsorbability, while the upper limit (50 mass%) prevents instability.
4Illumination intensity
If conventional bright pigments are used, then brightness is achieved, but biocompatibility is poor due to low oil adsorbability and instability
Solution Approach 1:
The composite particle structure combines biocompatible materials (glass or resin substrate, metal oxide coating, and amorphous calcium phosphate) in a way that maintains brightness while improving biocompatibility. The amorphous calcium phosphate outermost coating specifically enhances oil adsorbability and skin affinity, reducing potential harmful effects and improving safety for cosmetic applications.
Solution Approach 2:
Controlling the amorphous calcium phosphate content at 5-50 mass% and particle dimensions (1-10 μm diameter, 0.1-5 μm thickness) optimizes both brightness and biocompatibility, ensuring the pigment performs aesthetically while being safe for skin and nail applications.
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 bright pigment improves the cosmetic composition's spreadability, feel, and resistance to makeup deterioration, providing high biocompatibility and enhanced oil adsorbability, leading to better skin and nail care effects.
Implementation Method 1
cosmetic compositions containing such pigments are not satisfactory in spreadability, feel upon application and biocompatibility due to their poor oil adsorbability
Implementation Method 2
the outermost coating further comprises an anionic pigment having an acidic group and at least one member selected from the group consisting of a hydroxide of cerium, an oxide hydrate of cerium, a hydroxide of aluminum and an oxide hydrate of aluminum
Implementation Method 3
Such bright pigments reflect light on their surface and have glitter properties
Implementation Method 4
In synthetic mica-based pearlescent pigments, to superimpose another color on the interference color created by a colorless metal oxide coating layer
Data Source
Figure 1~3
AI summary
The bright pigment of the present invention contains a scaly substrate 10 and an outermost coating 20 that covers the scaly substrate 10, that is provided as an outermost layer, and that contains at least one member selected from the group consisting of hydroxyapatite and hydrocalumite. The bright pigment of the present invention may be further provided with an interference color coating that is disposed more towards the center than the outermost coating and that contains at least one metal oxide selected from the group consisting of titanium oxide and iron oxide. Moreover, the bright pigment of the present invention may be further provided with a silver-containing coating that is disposed more towards the center than the outermost coating and that contains silver and/or a silver alloy. The outermost coating may contain an anionic pigment.