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We report preliminary results of a broadband spectral and temporal study ofthe black-hole binary Cyg X-1 performed with the IBIS telescope. Cyg X-1 wasthe first pointed celestial target of IBIS during the INTEGRAL Performance andVerification Phase, 2002 Nov.-Dec., for a total observing time of 2 Ms in bothstaring and dithering mode. Here, we report on only the staring, on-axis,observation performed in a stable instrument configuration. During theobserving period the source was in its characteristic low/hard state, in whicha few flares and dips have been detected. The IBIS/ISGRI results demonstratethat the INTEGRAL observatory offers a unique capability for studyingcorrelations between hardness and/or flux in different bands over a wide photonenergy range. One of our new results is finding that the hardness-fluxcorrelation changes the sign twice over the 20-220 keV; first from positive tonegative at 50 keV, and then back to positive at 120 keV. The former changeappears to be due to the spectral curvature introduced by variable Comptonreflection. The latter may be due spectral pivoting.Comment: 7 pages, 8 figures (4 in color), accepted for publication in A&A,  INTEGRAL special issu

IBIS preliminary results on Cygnus X-1 spectral and temporal characteristics