A claim to the use of a known compound for a particular purpose (second non-medical use) which is based on a technical effect is interpreted as including that technical effect as a functional technical feature. Accordingly, said claim is not open to objection under Art. 54(1), provided that such technical feature has not previously been made available to the public (G 2/88, and G 6/88). The novelty of the use of the known compound for the known production of a known product cannot be deduced from a new property of the produced product. In such a case, the use of a compound for the production of a product has to be interpreted as a process for production of the product with the compound. It can be regarded as novel only if the process of production as such is novel (see T 1855/06). For claims to a second or further medical use, see G‑II, 4.2.
However, a feature of a step in a chemical process which merely serves to explain the technical effect obtained is not a functional technical feature which could render a claim novel over prior art which discloses the same process with the same step which provides the same effect, even if it does not comprise a corresponding indication of technical effect. It is rather considered to be a discovery (T 151/13).
Source: http://www.epo.org/law-practice/legal-texts/html/guidelines/e/g_vi_7_2.htm
Date retrieved: 17 May 2021