We have analysed high-dispersion echelle spectra ($R = 60000$) of red giant members of five open clusters to derive abundances for many elements from Na to Eu. The [Fe/H] values are $-0.06pm0.03$ for Stock 2, $-0.11pm0.03$ for NGC 2168, $-0.01pm0.03$ for NGC 6475, $0.00pm0.03$ for NGC 6991 and $-0.07pm0.03$ for NGC 7662. Sodium is enriched in the giants relative to the abundance expected of main sequence stars of the same metallicity. This enrichment of [Na/Fe] by about $+0.25$ attributed to the first dredge-up is discussed in the light of theoretical predictions and recently published abundance determinations. Abundance ratios [El/Fe] for other elements are with very few exceptions equal to those of field giants and dwarfs, i.e., [El/Fe] $simeq 0.00$ for [Fe/H] $sim 0.0$. An exception is the overabundance of La, Ce, Nd and Sm in NGC 6991 but this is consistent with our previous demonstration that the abundances of these $s$-process products vary by about $pm0.2$ among clusters of the same [Fe/H], a variation found also among field giants and dwarfs.
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