The sensible thermal heat storage mixture containing hydrated cobalt phosphate, anhydrous disodium hydrogen phosphate and sodium sulfate has been synthesized and characterized with different measurement techniques. The specific heat capacity was measured using Differential Scanning Calorimetry (DSC) at heating rate of 10 and 15 K min(-1) in atmospheric O-2. Both calcined and non calcined mixture show endothermic behaviour. This endothermic behaviour of these mixtures shows their potential to be used as thermal heat storage material. The endothermic behaviour of calcined mixture and also certain paint is reduced by using this mixture with paint in less than 1%. So, this composite material can be used as heat dissipating material. The calculated refractive index of these mixtures is similar to 2.55. The calculated band gap of both calcined and non calcined mixtures is 2.35 eV.