Hand sanitizers are primarily used for cleaning and protecting the skin. Some specific ingredients can provide disinfection and antibacterial properties, such as against E. coli. The main components of hand sanitizers are surfactants, deionized water, and a small amount of emollients. Auxiliary ingredients may include moisturizers, antibacterial agents, preservatives, fragrances, and pigments. Since hand sanitizers are applied directly to the skin, they have a higher pH requirement and are generally formulated as weakly acidic products. Therefore, soap-based surfactants are not typically used as the main surfactant. Additionally, hand sanitizers have relatively mild cleansing properties, and the most important aspect is to avoid degreasing. Therefore, the surfactant content in hand sanitizers should not be too high. Common surfactants used are AES and AESA, and some hand sanitizers use even milder sugar ester surfactants. Compared to body washes, hand sanitizers have a slightly lower surfactant content. Currently, alcohol-based hand sanitizers are also popular on the market, which evaporate quickly after washing, allowing hand sanitizers to be used without water. The main ingredient is alcohol, which can effectively kill germs.
I. Composition and Common Ingredients
The main function of hand soap is to clean and protect the skin, with some specific components that can disinfect and kill bacteria, such as E. coli. Its main components are surfactants, deionized water, and a small amount of emollients. Auxiliary components include moisturizers, bactericides, preservatives, fragrances, and pigments. Hand soap is directly applied to the skin, so it has higher requirements for pH value and is generally made into a slightly acidic product. Therefore, soap base is generally not used as the main surfactant. Moreover, its cleansing components are relatively mild, with the most important aspect being to avoid degreasing. Thus, the surfactant content in hand soap cannot be too high. The formulation still uses AES, AESA, etc., and some use milder sugar ester surfactants. Compared to shower gel, hand soap has a slightly lower surfactant content. Currently, alcohol-based hand sanitizers that evaporate quickly after use are also popular in the market, allowing hand cleaning to develop to a stage where water is not needed. Their main component is alcohol, which can effectively kill bacteria.
II. Formula Examples
1. Transparent Hand Soap
An example of a transparent hand soap formula is listed in Table 6-26. If you want to make a transparent hand soap with bactericidal function, you can add about 0.5% of chlorhexidine or other disinfectants to the formula.
| Component Name | Mass Fraction/% | Function |
|---|---|---|
| AES | 12.0 | Main surfactant, dirt removal |
| 6501 | 2.0 | Auxiliary surfactant, thickening, foam stabilizing |
| CAB-30 | 6.0 | Auxiliary surfactant, dirt removal, reducing irritation |
| EDTA-2Na | 0.1 | Chelating (removing the effect of calcium and magnesium ions) |
| Citric acid | 0.1 | pH adjustment (to slightly acidic) |
| Sodium chloride | 1.0 | Thickening |
| Glycerin | 1.0 | Moisturizing |
| Kathon | 0.1 | Preservative |
| Ethanol | 0.3 | Fragrance |
| Deionized water | Remainder | Solvent |
2. Pearlescent Hand Soap
An example of a pearlescent hand soap formula is listed in Table 6-27. If you want to make a transparent hand soap with bactericidal function, you can also add about 0.5% of chlorhexidine or other disinfectants to the formula.
| Component Name | Mass Fraction/% | Function |
|---|---|---|
| AESA | 12.0 | Main surfactant, dirt removal |
| 6501 | 2.0 | Auxiliary surfactant, thickening, foam stabilizing |
| CAB-30 | 6.0 | Auxiliary surfactant, dirt removal, reducing irritation |
| Pearlescent agent | 0.3 | Pearlescent effect |
| EDTA-2Na | 0.1 | Chelating (removing the effect of calcium and magnesium ions) |
| Citric acid | 0.1 | pH adjustment (to slightly acidic) |
| Ammonium chloride | 1.0 | Thickening |
| Glycerin | 1.0 | Moisturizing |
| Kathon | 0.1 | Preservative |
| Fragrance | 0.3 | Scent |
| Deionized water | Remainder | Solvent |