Unlike other liqueur makers who buy third-party produced essence, since summer 2013 and the launch of their new label and bottle, De Kuyper distil the...
De Kuyper made both a 20% "Curacao Triple Se and a 40% "Triple Sec". The 40% version is difficult to tell from Cointreau when blind tasting and is available from online retailers including www.TheWhiskyExchange.com
Could well be formulated from the same base with less alcohol and less sugar to retain balance. However, I don't consider a "triple sec" under 40% alc./vol. to be a triple sec as the alcohol strength is a major component in recipes such as the one above.