Your partner in precision urethane-based technology from prototype to production.

Your partner in precision urethane-based technology from prototype to production.

MPC Polyurethane Knowledge Center

Integral Skin Foam

What is Integral Skin Foam?

Integral skin foam, also commonly referred to as "self-skinning” foam, is a dual-layer structure formed through a material's foaming process. This composition, similar to a loaf of bread, features a foam inner core surrounded by a solid outer crust or “skin”. While several materials can be used to produce an integral skin foam, thermoset polyurethanes can offer customizable properties to meet exact design requirements, including density, hardnesses, tensile strength, chemical resistance, and many more. Due to its adaptability, polyurethane integral skin foams can be manufactured through a cast or Reaction Injection Molding (RIM) process.

Integral Skin Foam3

Benefits of Integral Skin Foam

There are 3 key things to consider in your product design when determining if integral skin foam is appropriate for your application, such as:


Integral skin foams can display a uniform surface that portrays either a smooth or textured finish. Because of this, product designers can eliminate painting or other secondary operations to achieve a nice aesthetic.


Integral skin foams can provide a different set of physical properties than the foam layer underneath. For example, the Coefficient of Friction (COF) of foam with an integral skin will be higher due to its smooth, shiny surface, while the exposed foam may portray a lower COF. 

Non Porous 

Integral skin foams can prevent any air, dust particles, or liquids from flowing through, creating a non-breathable material. Although closed-cell foams can be achieved without a skin, there is still some level of porosity left behind. To ensure the porosity of the cellular structure is completely closed, an integral skin may be recommended. 

How to use Integral Skin Foam in Your Design

2Integral skin foams can virtually be found anywhere that benefits from its physical properties. This is often determined by the product's overall function or purpose for optimal performance. For instance, products such as structural foam enclosures for robotics or elastomeric foam cushioning for fitness equipment may benefit from an integral skin due to its customizable aesthetics and superior properties. Whereas, products found in high-speed paper & media applications, such as foam rollers or belts, may exhibit poor COF and increased wear with an integral skin. While this material can offer a diverse set of capabilities, integral skin foams can also portray a negative effect on your product's performance if not used appropriately.   


Integral skin foams may be a key material for products and components that require a particular aesthetic or performance. As you further explore if integral skin foams are appropriate for your product design, it is important to consider your parts function, aesthetics, and physical property requirements beforehand. If you are still uncertain if integral skin foams are appropriate for your product design, take our design tool, here, or download our material data sheet below to learn more.

Download Our Durethane Material Data Sheet

About the MPC Knowledge Center

An informative site where you can learn all about product design using polyurethanes. We even answer the questions that Google can't!

Subscribe Here!