Hydroxypropylmethylcellulose (HPMC) is a synthetic polymer derived from cellulose, a natural polymer found in plants. It is commonly used in a variety of industries, including the pharmaceutical, food, construction, and personal care industries. While it’s not a typical ingredient in liquid soap, it can be used in some recipes to serve specific purposes.

In the case of liquid soap, the main ingredients are usually water, oil, or fat and a base that facilitates the saponification process (such as sodium hydroxide for bar soap or potassium hydroxide for liquid soap). Other ingredients can be added for various purposes such as fragrance, color and skin conditioning.

If HPMC is included in a liquid soap recipe, it may have a variety of uses:

Thickener: HPMC can be used as a thickener to provide a more viscous and stable consistency to liquid soap.

Stabilizer: HPMC helps improve the stability of the formulation and helps prevent ingredients from separating.

Enhanced lathering: In some cases, HPMC may help create a more stable, longer-lasting lather in soap.

Moisturizing: HPMC is known for its moisturizing properties that help retain moisture, thereby benefiting the skin.

It’s worth noting that the exact formulation of liquid soap can vary greatly depending on the manufacturer’s recipe and the desired properties of the final product. Be sure to check the ingredients list on the product packaging to see what ingredients are used in a specific liquid soap.

If you are interested in making your own liquid soap and considering using HPMC, it is recommended to carefully follow a tested recipe to ensure the proper balance of ingredients and achieve the desired results. Remember, the effectiveness of HPMC and other ingredients depends on their concentration and overall formulation.