Pure inorganic silica capsules were prepared using polyethoxysiloxane (PAOS) as a cross-linker, and the capsules contain inorganic hydrated salt inside. During this work, six different hydrated inorganic salts evaluated to be used as inorganic phase change materials (namely: calcium nitrate tetrahydrate (Ca(NO3)2.4H2O), calciumchloride hexahydrate (CaCl2.6H2O), sodium sulphate decahydrate (Na2SO4.10H2O), disodium hydrogen phosphate dodecahydrate (Na2HPO4.12H2O), ferric nitrate nonahydrate (Fe(NO3)3.9H2O), and manganese (II) nitrate hexahydrate (Mn(NO3)2.6H2O)) in silica-based micro-capsules. Inorganic phase change materials have been studied for their application in textiles. The best results are achieved for sodium sulphate decahydrate, and disodium hydrogen phosphate dodecahydrate, respectively. The microcapsules, which show good phase change property, were embedded in a film of the polypropylene at the extruding stage. The basic mechanical properties of the new material do not differ from those of the pure polypropylene.