We have gathered from the literature near and mid infrared (photometric and spectroscopic) data for Galactic planetary nebulae, with special attention to planetary nebulae surrounding Wolf-Rayet type central stars ([WR] PN). These data have been analyzed to obtain insight into the dust-properties of [WR] PN and their evolutionary status. We have found that a sizeable fraction of [WR] PN seems to contain hot dust (1000-2000 K), probably located in the winds of the central stars. The mean dust

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... perature is shown to decrease with decreasing [WC] spectral type. This is in line with suggestions that the [WC] sequence is an evolutionary sequence from late to early types. [WR] PN in different diagrams, when compared to those of non-[WR] PN, suggest that [WR] PN form a homogeneous class of planetary nebulae. There is an unusually large proportion of [WR] PN showing PAH features in their spectra.