Affine Lie Algebra Symmetry of Sine-Gordon Theory at Reflectionless Points

The quantum affine symmetry of the sine-Gordon theory at q^2 = 1, which occurs at the reflectionless points, is studied. Conserved currents that correspond to the closure of simple root generators are considered, and shown to be local. We argue that they satisfy the affine sl(2) algebra. Examples of these currents are explicitly constructed.