Patent ID: 7345141

Claim:
A polymer material having a carrier transport property, comprising at least one type of a crosslinkable functional group, wherein the polymer material has first and second states in which degrees of the carrier transport property are different from each other, microscopic structures in the first and second states are different from each other, and one of the first and second states can be changed into the other state, wherein the change is reversible, and wherein, in the first state, the crosslinkable functional group is in a crosslink dissociation state, and in the second state, the crosslinkable functional group is in a crosslink state, wherein in the crosslink state, the crosslinkable functional groups or the terminuses of the polymer are bonded in a chemical bonding state, and in the crosslink dissociation state, the crosslinkable functional groups or the terminuses of the polymer are not bonded or associated.