EMULSIONS IN SKINCARE

A Complete 3-Part Series for Formulators

Emulsions are the backbone of modern skincare. From lightweight lotions and gel-creams to rich night creams and sunscreens, most cosmetic products are built on oil + water systems held together by emulsifiers.

For DIY formulators, skincare brands, and cosmetic learners, understanding emulsions is essential to:• Create stable products• Prevent separation and spoilage• Improve texture, skin feel, and performance• Scale formulations confidently

This 3-part series explains emulsions from fundamentals to advanced troubleshooting, without unnecessary chemistry jargon.

PART 1: Emulsion Basics, Science & Types

Introduction

Before choosing an emulsifier or fixing a broken cream, it’s important to understand what emulsions are and how they work. This foundational knowledge helps you make better formulation decisions later.

What Is an Emulsion?

An emulsion is a mixture of two immiscible liquids (usually oil and water) that are kept together using an emulsifier.

Without an emulsifier:

• Oil floats

• Water settles

• Product separates

With an emulsifier:

• Oil droplets stay evenly dispersed

• Texture remains smooth

• Product remains stable over time

Common emulsion-based products:

• Face & body creams

• Lotions

• Conditioners

• Sunscreens

• Baby creams

The Science Behind Emulsions (Simple Explanation)

At a microscopic level:

• One phase is broken into tiny droplets (dispersed phase)

• The other phase forms the continuous phase

• The emulsifier surrounds each droplet and prevents them from merging

This results in:

• Smooth texture

• Even active distribution

• Improved absorption

• Better shelf stability

How Emulsifiers Work

An emulsifier acts like a bridge:

• One side loves water (hydrophilic)

• The other side loves oil (lipophilic)

This dual nature allows oil and water to remain together in a stable system.

Types of Emulsions Used in Skincare

1.     Oil-in-Water (O/W) Emulsions - Most common in skincare

Structure - Oil droplets dispersed in water

Skin feel - Light, non-greasy, fast absorbing

Best for -

• Face creams & lotions

• Gel-creams

• Summer products

• Oily to normal skin

Typical composition -

• Water: 60–80%

• Oil: 10–30%

2.    Water-in-Oil (W/O) Emulsions - Richer and more protective

Structure - Water droplets dispersed in oil

Skin feel - Rich, occlusive, nourishing

Best for -

• Cold creams

• Barrier repair creams

• Night creams

• Mature & very dry skin

• Winter skincare

Typical composition -

• Oil: 50–80%

• Water: 20–40%

3.    Multiple Emulsions - Advanced

Examples -

• W/O/W (water-in-oil-in-water)

• O/W/O systems

Used for -

• Controlled release of actives

• Dermatological & cosmeceutical products

• Require advanced emulsifiers, strict processing, and extensive testing.

Role of Emulsifiers in Skincare

Emulsifiers do more than just mix oil and water. They -

• Control viscosity

• Influence skin feel

• Improve active delivery

• Increase shelf life

• Prevent phase separation

Common Emulsifier Categories Used in Skincare

Category	Examples	Best Used For
Self-Emulsifying Systems	Sepigel 305, Simulgel	Beginner formulations, cold-process gel-creams
Wax-Based Emulsifiers	Emulsifying Wax (E-Wax NF), Olivem 1000, Polawax	Creams, lotions, body creams
Conditioning Emulsifiers	BTMS-25, BTMS-50	Hair conditioners, lotion-conditioners
Polymer-Based Emulsifiers	Sepimax ZEN, Aristoflex AVC	Gel-creams, serum-gels
Natural / Bio-Based	Lecithin, Glyceryl Stearate Citrate	Clean & ECO-friendly formulations
Co-Emulsifiers / Structuring Agents	Cetearyl Alcohol, Cetyl Alcohol	Stability, viscosity & texture
W/O Emulsifiers	Sorbitan Oleate, Polyglyceryl-4 Oleate	Cold & barrier creams

Notes for Formulators:

• E-Wax NF is one of the most beginner-friendly emulsifiers

• Wax-based emulsifiers require heating both phases

• Polymer emulsifiers allow cold processing and elegant textures

• Co-emulsifiers support structure but do not emulsify alone

• Natural emulsifiers require extra testing

• W/O emulsifiers are used for heavy, protective creams

Understanding emulsion basics is the foundation of successful formulation.

In Part 2, we’ll explore why emulsions break and how to keep them stable.