Urea-urethane gellant compositions and methods of preparing the urea-urethane gellant compositions. The method includes adding an isocyanate, an alcohol or a diamine, and a solvent to a reaction vessel; stirring the reaction vessel at either ambient or elevated temperature; isolating an intermediate product from the reaction vessel; and converting the intermediate product to the organic gellant. The urea-urethane gellants are prepared in a manner to control the molecular weight and control the formation of dimers and trimers. The gellants may be used in curable gel inks.