Why salted board can keep heat?

The reason why salted boards can insulate is that they are usually filled with high-density insulation materials, such as polyurethane foam or extruded polystyrene (XPS). These materials have excellent thermal insulation properties and can effectively reduce heat conduction. In addition, the surface of cold storage panels is usually sealed with a metal or polymer coating to prevent air flow and heat exchange, thereby further improving the insulation effect.