Yes, the record of individual transactions which occurred in the channel are not added to the Blockchain. Only the amount that is received by both parties at the close of the channel is made public when added to the Ethereum Blockchain. Furthermore, Raiden has expressed plans to enable 3rd parties to offer services to re-balance and obfuscate channel balances so that it is even harder to trace on-chain transactions to ones that took place in off-chain state channels.