Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Ceramide NP is a type of ceramide.

Ceramides are intercellular lipids naturally found in our skin that bonds dead skin cells together to create a barrier. They are known for their ability to hold water and thus are a great ingredient for dry skin.

Cetearyl alcohol is a mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is mainly used as an emulsifier. Emulsifiers help prevent the separation of oils and products. Due to its composition, it can also be used to thicken a product or help create foam.

Cetearyl alcohol is an emollient. Emollients help soothe and hydrate the skin by trapping moisture.

Disodium EDTA plays a role in making products more stable by aiding other preservatives.

It is a chelating agent, meaning it neutralizes metal ions that may be found in a product.

Ethylhexylglycerin (we can't pronounce this either) is commonly used as a preservative and skin softener. It is derived from glyceryl.

You might see Ethylhexylglycerin often paired with other preservatives such as phenoxyethanol. Ethylhexylglycerin has been found to increase the effectiveness of these other preservatives.

Glycerin is already naturally found in your skin. It helps moisturize and protect your skin.

A study from 2016 found glycerin to be more effective as a humectant than AHAs and hyaluronic acid.

Glyceryl Stearate is a mix of glycerin and stearic acid.

It is used to stabilize the mixing of water and oil ingredients. By preventing these ingredients from separating, it can help elongate shelf life. It can also help thicken the product's texture.

Hydroxyacetophenone is antioxidant with skin conditioning and soothing properties. It also boosts the efficiency of preservatives.

This ingredient is not irritating or sensitizing.

Polyacrylate-13 is a type of acrylate polymer. Acrylate polymers are commonly used as adhesives in cosmetics.

Polyacrylate-13 creates a film to protect the skin. It is also used to thicken and stabilize a product. It works by making water a gel-like consistency. This gel consistency helps suspend particles.

Polyisobutene is a synthetic polymer made from isobutene.

It is a film-forming agent and helps bind ingredients together.

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin. 

It’s often used to:

Sorbitan Isostearate is an emulsifer and cleaning agent. It is created from isostearic acid and sorbitol.

As an emulsifier, Sorbitan Isostearate prevents oils and water from separating.

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.