Thermal jackets bear fantastic thermal properties. They are often used as a replacement for the standard thermal lining that is present in many textile motorcycle jackets anyway. An extra layer can also come in very handy when a motorcycle jacket doesn't guarantee the warmth that you prefer.
A thermal jacket is usually finished in such a way that it can be worn as a casual jacket next to the motorcycle perfectly. Most of them are made of softshell, because of the excellent thermal properties of this material.