Alkyl sulfate salt is another common cleaning ingredient. It has strong cleaning power, rich foam, and is easily soluble in water. It can be used alone or together with other cleaning ingredients. The price is very low, so it is widely used in cleaning cosmetics. Wide range of applications.
How to judge?
The method of judging this type of ingredient is very simple. As long as you see the word “sulfuric acid” in the ingredient list of facial cleansers, you can be sure. There are two typical representatives of sulfate ester salts: one is sodium lauryl sulfate, the abbreviation is SLS; the other is sodium laureth sulfate, the abbreviation is SLES.
Pros and Cons of SLS
Pros
Sodium lauryl sulfate has excellent cleaning performance and is widely used in facial cleansers, shampoo, body wash, and toothpaste. Sodium lauryl sulfate, in particular, is found in most shampoos and toothpaste.
In recent years, the concept of silicone-free shampoo has been popular. Silicone-free oil refers to shampoos that do not contain sulfate salts. It can be said that silicone oil is a scapegoat for sulfate salts.
Cons
The disadvantage of sodium lauryl sulfate is that the cleaning power is too strong and can irritate the skin, so it is often used in research on anti-inflammatory effects.
For example, apply sodium lauryl sulfate on the skin to cause inflammation, and then apply it with a certain plant extract for comparison. If the inflammation is significantly improved, it can be said that this plant extract has anti-inflammatory effects.
Therefore, cleansing products containing sodium lauryl sulfate should also be used scientifically. It is also suitable for healthy oily skin to use in summer evenings. It can be used for weekly care in spring, autumn, and winter, and once a week is enough. Normal and dry skin should be used sparingly; sensitive skin should be kept at a respectful distance.
Practical Application
There are many cleaning products containing sodium lauryl sulfate, such as a facial cleansers, whose full ingredients are as follows:
Water, Cetyl Alcohol, Propylene Glycol, Sodium Lauryl Sulfate, Stearyl Alcohol, Methylparaben, Propylparaben, etc.
The formula of this product is very simple. It gained much fame when it first entered the market by claiming “zero stimulation.” I also used to praise this product very much, thinking that the formula is streamlined and can be used for dry or sensitive skin.
However, with the expansion of its popularity, many customers and formulation experts have questioned and criticized this product. The biggest complaint about it is that it cannot be washed clean.
From the formula point of view, only sodium lauryl sulfate can play a cleaning role, and its cleaning power is relatively strong. If the facial cleanser with this ingredient is still unclear, it proves the amount added is too small. Since the amount added is very small and irritating, why should it be added?
Mr. Charlie, a well-known formulation engineer in the industry, believes that the most important thing for sodium lauryl sulfate in this system is not to act as a cleaning ingredient but as an emulsifier to emulsify the relatively high amount of cetyl alcohol and stearyl alcohol. Propylene glycol only acts as a dispersant and solvent so this facial cleanser can be understood as a cream.
Since the amount of sodium lauryl sulfate added is very small, the cleaning power and irritation are relatively low. Still, oily skin will feel that its cleaning power is too weak, and sensitive skin will worry about the irritation of sodium lauryl sulfate. This product gives people a feeling of being unflattering on both sides.
So I also want to correct some of my previous incorrect views. It is better to use this cleanser sparingly for dry and sensitive skin.
Summary
Sodium lauryl sulfate is cheap and easy to use, but its cleaning power and irritation are too strong, which can easily cause over-cleaning and skin irritation. It is only suitable for healthy oily skin at night in summer and can be used for weekly care in spring, autumn, and winter.