Pressure-sensitive adhesive composition and pressure-sensitive adhesive sheet

A pressure-sensitive adhesive composition, comprising:

• a (meth)acrylate copolymer (A) obtained by copolymerizing a (meth)acrylate and a reactive group-containing monomer, such that a ratio of the reactive group-containing monomer in the copolymer ranges from 0.01 to 15 wt %;
• a polyrotaxane (B) having at least two cyclic molecules and a linear-chain molecule passing through opening portions of the cyclic molecules wherein the cyclic molecules have each one or more reactive groups and the linear-chain molecule has blocking groups at both ends thereof;
• and
• a crosslinking agent (C) having a reactive group capable of reacting with the reactive group of the (meth)acrylate copolymer (A) and with the reactive group of the polyrotaxane (B),
• wherein an equivalent ratio of the reactive group of the crosslinking agent (C) with respect to the reactive group of the (meth)acrylate copolymer (A) ranges from 0.001 to 2, and
• an equivalent ratio of the reactive group of the crosslinking agent (C) with respect to the reactive group of the polyrotaxane (B) ranges from 0.1 to 5.