TECHNOLOGY FOCUS - IMAGING AND COMMUNICATION - Preferred Composition: The nano ink comprises 10-70 parts by weight of (I), 0.1-10 parts by weight of the dispersant, and 20-82 parts by weight of the solvent. Preferred Process: The sintering step is performed at 300-500 degrees C. The step of applying on the substrate is performed by inkjet printing.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preparation (Claimed): Preparation of (I) comprises: mixing and reacting titanium isopropoxide with the surface stabilizer in a solvent; and evaporating the solvent from thus produced titanium dioxide colloid. Preferred Process: In the method of preparing (I), 5-8 vol.% of titanium isopropoxide is mixed with 0.1-1 vol.% of the surface stabilizer and 91-94 vol.% of the solvent. Preferred Components: (I) has a diameter of 3-30 nm.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The solvent is an alcohol, a glycol or a glycol ether, preferably methanol, ethanol, propanol, isopropanol, butanol, pentanol, hexanol, dimethyl sulfoxide, dimethylformamide, dimethylformamide, glycerol, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol and/or propylene glycol propyl ether.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The dispersant is a copolymer of formula (-(CH2CH2O)n-(CH(CH3)CH2O)m-) or ester compounds of formula (d).m, n = 1-30.The copolymer has a polyethylene oxide content of 30-80 wt.% based on the total weight of the copolymer. EXAMPLE - Toluenesulfonic acid (1.72 ml) was dissolved in butanol (25 ml). After mixing butanol (150 ml) with Millipore water (5 ml) and adding titanium isopropoxide (12 ml), the resultant mixture was added to the toluenesulfonic acid solution. The mixture was reacted at room temperature for 1 hour and then at 110 degrees C for 6 hours. The reaction was preceded further by adding phenylsulfonic acid. The solvent was evaporated from the resultant titanium dioxide colloid solution to adjust the volume to 120 ml.