Foams typically fall into one of two categories. Open Cell, and Closed Cell. There is also a mixture of the two which is often called a semi open cell foam.

Foam structures consist of a flexible material that is filled with voids, or bubbles. Two of the primary categories of foam are open cell foam and closed cell foam.

Foams are generated by forming gas bubbles in a liquid base which then begins to set over a short period of time, and the properties of the liquid and gas determines the final foam structure.

The distinction between Closed Cell and Open Cell Foam

  • Closed cell foam – the bubbles are completely encompassed within the liquid and when it sets, the gases are entirely fixed within each individual bubble, creating a structure that is impervious.
  • Open cell foam – the bubbles burst during the foaming process to create and interconnection cellular network. This gives rise to softer and breathable foams.
  • Semi-Open Cell foam – this is created by physically bursting the closed cells to create a more open cell product which is softer and easier to compress.