Triarylmethane Dye Composition with Amino Silicones for Hair Fastness
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing hair dye compositions using direct dyes, particularly those of triarylmethane structure, suffer from weak dyeing power and poor persistence due to temporary or semi-permanent binding to keratin fibers, leading to inadequate color intensity and resistance against washing, light, and external agents like shampoos and perspiration.
Innovation Solution
A composition combining cationic or anionic triarylmethane dyes with amino silicones and surfactants in an acidic medium, enhancing color development and fastness on keratin fibers, especially on previously lightened hair, achieving strong, chromatic, and varied shades with improved resistance to washing and external factors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If direct dyes of triarylmethane structure are used to obtain chromatic coloring, then color intensity is improved, but fastness with respect to washing deteriorates
Solution Approach 1:
The patent combines direct dyes of triarylmethane structure with amino silicones and surfactants to create a composite dyeing composition. The amino silicones form a protective complex with the dye molecules on the hair fiber surface, enhancing both color intensity and washing fastness simultaneously. This composite approach allows the dye to penetrate and bind to keratin while the silicone component provides a durable coating that resists washing.
2Ease of operation
If direct dyes are applied to obtain temporary or semi-permanent coloring, then ease of fading out is improved, but dyeing power deteriorates
Solution Approach 1:
The patent modifies the chemical parameters of the dyeing system by adjusting pH levels and incorporating specific amino silicones that alter the binding characteristics. The composition achieves strong initial dyeing power through optimized dye-fiber interaction at controlled pH, while maintaining ease of fading through the reversible nature of the amino silicone-dye complex that can be gradually removed with repeated washing.
3Adaptability or versatility
If direct dyes are used on sensitized or bleached hair, then adaptability to different hair types is improved, but fastness with respect to washing deteriorates
Solution Approach 1:
The amino silicones act as intermediary agents between the direct dyes and the sensitized or bleached hair. These intermediaries provide a stable binding interface that compensates for the altered hair structure, allowing the dye to adhere strongly to compromised hair fibers while maintaining washing fastness. The surfactants further mediate by ensuring uniform distribution and penetration into the porous structure of treated hair.
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 strong, long-lasting color with reduced selectivity, achieving better color build-up on grey hair and improved resistance to washing and external agents, ensuring a more durable and aesthetically pleasing hair color.
Implementation Method 1
the nature of the interactions that bind the direct dyes to the keratin fibre and their desorption from the surface and/or the core of the fibre are responsible for their weak dyeing power and their poor relative persistence
Data Source
AI summary
The present invention relates to a composition for dyeing keratin fibres comprising, in a cosmetically acceptable medium: —one or more direct dyes of triarylmethane structure, —one or more amino silicones and—one or more surfactants. The invention also relates to a process for dyeing keratin fibres using said composition and also to a use for dyeing keratin fibres.