Adhesive film for surface protective film, and optical member comprising same

An adhesive film for surface protection formed of a composition for adhesive films comprising a urethane-based binder and an isocyanate curing agent,

• the adhesive film having an increase rate of peel strength of 180% or less, as calculated by Equation 1:
• Increase rate of peel strength=[(P2−P1)/P1]×100 [Equation 1]
• where, in Equation 1,
• P1 is an initial peel strength of the adhesive film (unit:
• gf/inch), and
• P2 is peel strength of the adhesive film, as measured after leaving the adhesive film at 50° C. for 3 days and at 25° C. for 30 minutes (unit:
• gf/inch),
• the adhesive film having an initial peel strength of 1 gf/inch to 12 gf/inch, a nitrogen (N) atom content of 0.5 wt % to 1.50 wt % relative to all atoms therein, and a modulus of 0.05 MPa to 0.8 MPa at 25° C.