How to Choose the Right Thickener for Your Cosmetic Formulation

A Beginner’s Guide for Creams, Gels & Serums

In cosmetic formulation, choosing the right thickener is essential for creating products with the desired texture, stability, and performance. Thickeners not only control viscosity but also influence the feel, spreadability, and stability of a formulation.

For beginners, selecting the correct thickening agent can sometimes feel confusing because different thickeners behave differently depending on the formulation type.

This guide explains how to choose the right thickener based on the type of product you want to create.

What Do Cosmetic Thickeners Do?

Thickeners are ingredients that increase the viscosity of a formulation, helping transform a liquid base into a gel, cream, or lotion.

They play several important roles in cosmetic formulations:

• Increase viscosity and thickness

• Improve product texture and spreadability

• Stabilize emulsions

• Suspend particles and active ingredients

• Prevent ingredient separation

Without a suitable thickener, many cosmetic products would feel watery or unstable.

Types of Cosmetic Thickeners

Cosmetic thickeners generally fall into three main categories.

1.     Polymer-Based Thickeners

These are synthetic polymers commonly used in modern cosmetic formulations.

Examples include:

• Carbomer

• Sepimax ZEN

• Aristoflex AVC

• Acrylates Crosspolymers

They provide excellent viscosity control and are widely used in gels and gel creams.

2.    Natural Thickeners

Natural thickeners are derived from plant or microbial sources and are commonly used in natural or herbal formulations.

Examples include:

• Xanthan Gum

• Guar Gum

These thickeners are suitable for formulations where a natural origin is preferred.

3.    Cellulose-Based Thickeners

Cellulose derivatives are widely used because of their compatibility with surfactants and other ingredients.

Examples include:

• Hydroxyethyl Cellulose (HEC)

These work particularly well in cleansers and shampoos.

Choosing the Right Thickener Based on Product Type

The most important factor when choosing a thickener is the type of product you are formulating.

1.     For Clear Gels

Carbomer is one of the most commonly used thickeners for clear gels. It provides strong viscosity and creates crystal-clear formulations when neutralized properly.

Suitable products include:

• Face gels

• Aloe gels

• Gel serums

• Hair styling gels

2.    For Gel Creams

Gel creams require thickeners that can handle small amounts of oils while maintaining a smooth texture.

Suitable options include:

• Sepimax ZEN

• Aristoflex AVC

These ingredients create elegant textures often seen in premium skincare products.

3.    For Creams and Lotions

Emulsion-based products need thickeners that also help stabilize oil and water phases.

Acrylates/C10-30 Alkyl Acrylate Crosspolymer is often used in these formulations because it improves both viscosity and emulsion stability.

4.    For Cleansers and Shampoos

Surfactant-based products require thickeners compatible with cleansing agents.

Hydroxyethyl Cellulose works well in:

• Face cleansers

• Body washes

• Shampoos

It provides smooth viscosity without affecting foam performance.

5.    For Natural Formulations

If you are formulating natural or herbal skincare products, natural thickeners are often preferred.

Xanthan gum is widely used because it:

• Hydrates easily in water

• Works in cold process formulations

• Helps stabilize emulsions

Guar gum is also commonly used in hair care products.

Factors to Consider When Selecting a Thickener

Choosing the right thickener is crucial for achieving the desired texture, stability, and performance in cosmetic formulations. Different thickeners behave differently depending on the formulation environment.

When selecting a thickener, consider the following formulation factors:

1.     Product Texture

The desired final texture of the product is one of the most important considerations.

Some thickeners create clear gels, while others work better in creams or gel-creams.

Examples

• Carbomer → Ideal for clear gels such as aloe gels, hand sanitizers, and hydrating serums.

• Sepimax ZEN → Suitable for gel-creams and modern skincare textures.

• Acrylates Crosspolymer → Often used in creams and lotions for viscosity and stability.

• Xanthan Gum → Common in natural creams and gels.

Example formulation

A hydrating face gel with hyaluronic acid usually works best with Carbomer or Sepimax because they create a smooth, transparent gel.

2.     Oil Content

Some thickeners can tolerate oils, while others perform best in oil-free formulations.

If the formulation contains oils or emollients, the thickener must be able to stabilize oil-water interactions.

Examples

• Carbomer → Works best in low-oil or oil-free gels.

• Sepimax ZEN → Can tolerate oils and emollients, making it suitable for gel creams.

• Acrylates Crosspolymer → Excellent for emulsions and creams containing oils.

Example formulation

A gel moisturizer containing 5–10% oils would perform better with Sepimax ZEN than with Carbomer.

3.     Electrolytes

Electrolytes such as salts, botanical extracts, minerals, or certain active ingredients can affect the performance of some polymers.

Certain thickeners lose viscosity when exposed to high electrolyte levels.

Examples

• Aristoflex AVC → Sensitive to electrolytes (salts, sodium PCA, herbal extracts).

• Carbomer → Moderate tolerance but can lose viscosity in complex formulas.

• Sepimax ZEN → High electrolyte tolerance.

Example formulation

A gel containing niacinamide, aloe extract, and plant extracts would be more stable with Sepimax ZEN than Aristoflex.

4.    Processing Method

Different thickeners require different processing conditions such as neutralization, heating, or cold processing.

Choosing the right thickener can simplify the formulation process.

Examples

• Carbomer → Requires neutralization with TEA or NaOH.

• Sepimax ZEN → Cold-process polymer, no neutralization required.

• Hydroxyethyl Cellulose (HEC) → Requires hydration but no neutralization.

• Xanthan Gum → Often pre-mixed with glycerine for easier dispersion.

Example formulation

For quick DIY gel formulations, many formulators prefer Sepimax ZEN because it allows cold processing.

5.     Skin Feel

Each thickener creates a different sensory experience on the skin.

Some polymers produce lightweight, silky gels, while others create thicker or slightly sticky textures.

Examples

• Aristoflex AVC → Creates silky, elegant textures ideal for serums.

• Carbomer → Produces lightweight clear gels.

• Xanthan Gum → Can create slightly stringy or natural textures.

• Sepimax ZEN → Provides smooth, cushion-like gel feel.

Example formulation

A luxury hydrating serum often uses Aristoflex or Sepimax because they produce a more elegant skin feel.

Quick Guide: Which Thickener to Use

Product Type	Recommended Thickener
Clear gels	Carbomer
Gel creams	Sepimax / Aristoflex
Cream emulsions	Acrylates Crosspolymer
Cleansers	Hydroxyethyl Cellulose
Natural products	Xanthan Gum
Hair care products	Guar Gum

Final Thoughts

• Selecting the right thickener is an important step in cosmetic formulation. Each thickening agent has its own strengths and ideal applications.

• Understanding these differences helps formulators create products that are stable, aesthetically pleasing, and easy to apply.

• By choosing the appropriate thickener for your formulation, you can significantly improve both the performance and the sensory experience of your product.

Disclaimer

This article is intended for educational and formulation guidance purposes only. Cosmetic formulations require proper testing before commercial use. Always perform stability testing, compatibility testing, pH analysis, and microbial testing to ensure product safety, quality, and shelf stability.