Process for preparation of silver nanoparticles, and the compositions of silver ink containing the same

A method for preparation of silver nanoparticles comprising the steps of:

• a) preparing a silver complex compound by reacting the silver compound represented by the following formula 1 with at least one or two mixtures selected from ammonium carbamate compound, ammonium carbonate compound or ammonium bicarbonate compound represented by the following formulas 2 to 4;
• and
• b) preparing the silver nanoparticles by reacting the silver complex compound prepared in the a) step with a reducer, or by reducing or pyrolyzing the silver complex compound by applying heat thereto,
• from the above formulas 1 to 4, X represents a substituent selected from oxygen, sulfur, halogen, cyano, cyanate, carbonate, nitrate, nitrite, sulfate, phosphate, thiocyanate, chlorate, perchlorate, tetrafluoro borate, acetylacetonate, carboxylate, and the derivatives thereof;
• n represents integers of 1 to 4;
• R1 to R6 are independently hydrogen, C1-C30 aliphatic or cycloaliphatic alkyl group or C6-C20 aryl or their mixture of aralkyl group, alkyl and aryl group where functional group is substituted and heterocyclic compound and polymer compound and the derivatives thereof;
• and R1 and R2 and, independently, R4 and R5 may form a ring by being connected in alkylene independently including heteroatom or not including thereof, with a proviso that not all of R1 through R6 are hydrogen.