Thermal transfer film, and organic electroluminescent device prepared using same

A thermal transfer film comprising:

• a base layer;
• and
• a light-to-heat conversion layer formed on the base layer, the light-to-heat conversion layer comprising a cured product of a composition for a light-to-heat conversion layer, the composition comprising a UV curable resin, a polyfunctional monomer, a light-to-heat conversion material and an initiator,
• wherein the light-to-heat conversion layer is a single layer having a first region adjacent the base layer in a thickness direction and a second region adjacent the first region in a thickness direction, and
• the light-to-heat conversion material is more distributed in the first region than in the second region, and wherein the second region has a surface roughness (Ra) of about 10 nm or less on its upper surface.