Methods and compositions for films, masterbatch, yarns, fabrics, and articles comprising same

A method of forming a cooling film, comprising:

• placing a plurality of sputtering targets in a sputtering chamber of sputtering device;
• placing a substrate in a substrate holder disposed above the plurality of sputtering targets;
• applying a DC magnetic field to the sputtering targets;
• and
• depositing at least one layer of sputtered material on a surface of the substrate;
• wherein the plurality of sputtering targets comprise a sputtering material selected from aluminum metal and a combination of aluminum metal and zinc oxide;
• wherein the layer of sputtered material comprises nanoparticles of a cooling composition;
• wherein the cooling composition comprises a material selected from aluminum metal and combination of aluminum metal and zinc oxide;
• and
• wherein the substrate comprises a polymer;
• wherein the substrate is a film;
• wherein the film has a thickness of about 5 μm to about 20 μm;
• wherein the particles of the sputtered material have an average particle size from about 1 nm to about 50 nm;
• and
• wherein the particles of the sputtered material are present in an amount of from about 0.01 wt % to about 1 wt % based on the total weight of the cooling film;
• thereby forming a cooling film comprising a substrate having thereon a layer of sputtered material.