TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The metal nanoparticles or metal-containing precursors are water soluble, and not soluble in non-polar organic solvent. The metal nanoparticles or metal-containing precursors are capped with hydrophilic surfactants. The metal nanoparticles or metal-containing precursors comprise a metal element comprising gold, silver, palladium, platinum, copper, chromium, nickel, cobalt, manganese, iron, aluminum, an alkaline earth metal, an alkali metal, a transition metal, a lanthanide, a poor metal, and/or an actinide. The metal-containing precursors are metal colloids, organic metal compound, organic metal complex, and metal reducible salts which can decompose to form conductive metals. The metal-containing precursors are silver formate, silver acetate, silver halide, and silver oxalate.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Composition: The composition comprises 60-90 wt.% of water; 10-40 wt.% of metal nano-particles or metal-containing precursors; and 1-6 wt.% of foam forming chemical or bubble agent. The composition further comprises: up to 10 wt.% of a water-miscible secondary solvent; and an agent comprising foam stabilizer, humectant, adhesion promoter, binder, surfactant, additive, polymer, buffer, thickener or viscosity modifier, dispersant, and/or coupling agent. Preferred Components: The hydrophilic surfactants are gum Arabic, ammonium stearate, stearate salts, polyethylene glycol, polyvinyl pyrrolidone, polyvinyl alcohol, cellulose derivatives, polyacrylamide and copolymers, acrylic acid copolymers, vinylmethyl ether-maleic anhydride copolymers, vinyl acetate-maleic anhydride copolymers, salts of naphthalene sulfonic-formaldehyde copolymers, styrene-maleic anhydride copolymers, calcined dextrin, acid decomposed dextrin, acid-decomposed etherified dextrin, agarose, and salmon sperm DNA. The metal nanoparticles have an average size of 1-500 nm. The foam forming chemical or bubble agent is anionic foam forming chemical, cationic foam forming chemical, organic amine soaps, and metallic foam forming chemical. The water-miscible secondary solvent is ethanol, methanol, and ethyl alcohol. The humectant constitutes up to 2 wt.% of the composition. The thickener or viscosity modifier constitutes up to 2% of the composition. The surfactant constitutes up to 3 wt.% of the composition. The adhesion promoter constitutes up to 3 wt.% of the composition. EXAMPLE - Metal nanoparticles (silver nanoparticles having an average particle size of 80 nm) (10 g), water (42.2 g), a foam forming chemical (Macare G-2C (RTM: Multifunctional co-surfactant for toiletries performing as a thickener, foam booster, skin and hair moisturizer and emollient)) (2.2 g), a viscosity modifier (cocamidopropyl betaine) (0.28 g), a surfactant (Synperonic 91/6 (RTM: Synthetic alcohol ethoxylate)) (0.55 g), and an adhesion promoter (Cartacoat B750 (RTM: Rheology modifiers)) (0.28 g) were mixed to obtain the composition.