Thermal transfer sheet, coating liquid for release layer, and method for producing thermal transfer sheet

A thermal transfer sheet comprising:

• a substrate;
• and
• a transfer layer provided on the substrate,
• wherein the transfer layer has a single-layer structure consisting of a protective layer or a layered structure including a protective layer,
• wherein the protective layer contains a cured product of an active ray-curable resin,
• wherein an initial breakage peeling-off force when the transfer layer is peeled under conditions of a peeling-off temperature of 20° C. or more and 40° C. or less and a peeling-off angle of 90° is 49 N/m or less, and
• wherein the protective layer further comprises a first filler having a volume average particle size in a range of 0.1 μm or more and 2 μm or less, and a second filler having a volume average particle size of 40 nm or less.