CRISIL has upgraded Tata Chemicals' non-convertible debenture (NCD) programmes from "AA/positive" to "AA+/stable". The upgrade is based on benefits expected to arise from Tata Chemicals' acquisition of Hind Lever Chemicals under a share swap agreement and the improvement in Tata Chemicals' financial profile with reduction in debt level and interest costs. The merger with HLCL would strengthen Tata Chemicals' business profile by imparting greater diversity to its revenue stream.