The flight crew received taxi clearance to runway 22 at 1009. Their instrument flight rules (IFR) clearance was received and read back while taxiing. During taxi, the crew was asked to expedite taxiing because of traffic on a 12-mile final approach to runway 31. The aircraft was then directed to turn right onto runway 22, and, at 1014, take-off clearance was issued and acknowledged. Take-off did not commence until approximately 45 seconds after the take-off clearance was acknowledged. There were no further transmissions from the aircraft after the acknowledgement of the take-off clearance.