Antimicrobial Bar Composition via Acidic pH Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing cleansing compositions, particularly soap bars, often lack sufficient antimicrobial activity, especially against Gram-negative bacteria, and may not be mild enough for skin use while being free from harsh ingredients.
Innovation Solution
A mild bar composition comprising 18-65% anionic surfactant and 0.2-8% acid with a pKa from 1 to 8 and log P from 0 to 4.95, formulated to generate a wash slurry with a pH of 2.9 to 5.2, and optionally free from ethanol, parabens, formaldehyde donors, silicones, sulfates, and halogenated antimicrobial actives.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional soap bars are used, then cleansing ability is provided, but antimicrobial activity against Gram-negative bacteria is insufficient
Solution Approach 1:
The patent changes the pH parameter of the wash slurry to a range of 2.9-5.2, which is significantly lower than traditional soaps. This pH modification creates an acidic environment that enhances antimicrobial activity against both Gram-negative and Gram-positive bacteria while maintaining skin compatibility. The acidic pH is achieved through the selection and combination of specific acid components with appropriate pKa values.
Solution Approach 2:
The invention uses a composite formulation combining anionic surfactants with multiple acid components (having specific pKa and log P ranges). This composite approach creates synergistic effects where the surfactant provides cleansing while the acids provide antimicrobial activity, achieving both functions in a single mild bar composition without requiring harsh ingredients.
2Reliability
If harsh ingredients are used to achieve antimicrobial activity, then biocidal action is improved, but mildness on skin deteriorates
Solution Approach 1:
The patent modifies the chemical parameters by using acids with specific pKa (1-8) and log P (0-4.95) ranges, creating a mildly acidic environment that is effective against bacteria but compatible with skin physiology. This parameter optimization allows achieving antimicrobial activity without the need for harsh biocides that would damage skin.
Solution Approach 2:
The invention replaces expensive and potentially harmful long-term antimicrobial agents with a mild acidic system that works effectively during the short duration of washing (seconds to minutes). The acid provides sufficient antimicrobial action during the wash cycle without requiring persistent residual activity that would necessitate harsh ingredients.
3Object-affected harmful factors
If the bar composition is formulated to be mild and free from harsh ingredients, then skin compatibility is improved, but antimicrobial efficacy deteriorates
Solution Approach 1:
The patent achieves this resolution by changing the pH parameter to 2.9-5.2 and selecting acids with specific pKa and log P ranges. This creates a mildly acidic formulation that is both skin-compatible and highly effective against bacteria, including Gram-negative species. The acidic environment disrupts bacterial cell membranes without requiring harsh surfactants or biocides.
Solution Approach 2:
The anionic surfactant in the formulation serves multiple functions: it provides cleansing action, creates lather, and when combined with the acid system, contributes to the overall antimicrobial efficacy. This multi-functionality allows the mild bar to achieve both skin compatibility and broad-spectrum antimicrobial activity without needing separate harsh ingredients for each function.
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 bar composition achieves superior antimicrobial activity, providing a Log10 reduction of at least 1.0 against E. coli and S. aureus within 15 seconds, and up to 3.0 after 40 seconds, while maintaining mildness on the skin.
Implementation Method 1
The bar composition comprises an anionic surfactant and an acid, and is formulated, when lathered, to generate a wash slurry having a pH from 2.9 to 5.2
Data Source
AI summary
The present invention is directed to a mild bar composition with enhanced antimicrobial activity. The bar composition of the present invention is mild and unexpectedly yields superior antimicrobial activity when used in cleansing applications. The bar composition comprises an anionic surfactant and an acid, and is formulated, when lathered, to generate a wash slurry having a pH from 2.9 to 5.2.