Oxidative Hair Dye Viscosity Stabilization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The use of α-naphthol as a coupler in oxidative hair dye compositions leads to instability in viscosity, causing issues such as dripping when used in cream-state formulations with low viscosity.
Innovation Solution
Incorporating a predetermined oily component and a nonionic surfactant with a polyoxyethylene chain having 20 or more moles of ethylene oxide, along with α-naphthol, to stabilize the viscosity of the oxidative hair dye composition, with specific ratios and ranges for these components to enhance stability and application properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If α-naphthol is used as a coupler in oxidative hair dye composition, then the hair-dyeing power is improved, but the viscosity stability of the composition deteriorates
Solution Approach 1:
The patent introduces a specific oily component as an intermediary substance that mediates between α-naphthol and the cream base. This oily component prevents direct harmful interactions while maintaining the dyeing effectiveness of α-naphthol, thereby resolving the contradiction between hair-dyeing power and viscosity stability.
Solution Approach 2:
The patent changes the physical-chemical parameters of the composition by selecting specific oily components with particular molecular structures and properties. By adjusting the type and amount of oily component, the patent optimizes both the solubility of α-naphthol and the overall viscosity stability of the cream formulation.
2Ease of operation
If the viscosity of cream-state oxidative hair dye is reduced to improve application properties, then the ease of operation is improved, but the viscosity stability deteriorates causing dripping
Solution Approach 1:
The patent creates a composite cream formulation that integrates multiple components including α-naphthol, oily component, oxidant, and cream base. This composite structure allows the formulation to maintain low viscosity for easy application while the synergistic interaction between components provides sufficient viscosity stability to prevent dripping.
Solution Approach 2:
The patent applies local quality by having different components perform specialized functions: the oily component specifically addresses viscosity stability, while other components handle dyeing power and application properties. This functional differentiation allows the overall formulation to achieve low viscosity without sacrificing stability.
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 combination improves viscosity stability, prevents viscosity degradation, and maintains application properties, ensuring a stable and effective hair dyeing process without dripping, even at lower viscosities of 3,000 to 10,000 mPa·s.
Implementation Method 1
a nonionic surfactant having a polyoxyethylene chain having a number of moles of added ethylene oxide of 20 or more
Implementation Method 2
The oxidative dye is a compound capable of developing a color due to the oxidation polymerization caused by the oxidant contained in the second agent
Data Source
AI summary
An oxidative hair dye composition includes an alkaline agent and an oxidant. The oxidative hair dye composition further includes (A) α-naphthol in a content of 0.005 to 0.45% by mass, (B) at least one oily component selected from a higher alcohol, an ester, and a wax that are in a liquid state at 25° C., and (C) a nonionic surfactant having a polyoxyethylene chain having a number of moles of added ethylene oxide of 20 or more.