US Patent 7789481 Ink jet recording apparatus

An ink-jet recording apparatus includes a rubber member in an ink flow passage. The rubber member is made of a rubber composition including a rubber base polymer selected from ethylene-propylene diene rubber polymer and isobutylene-isoprene rubber polymer, and at least one trapping agent selected from calcium carbonate, silicon dioxide, talc, and clay. The trapping agent is effective for absorb-trapping various types of additives that may be present in the rubber member. The additives in the rubber are thereby held in the rubber structure and prevented from being eluted into the water-based ink or the preservative solution, which can lead to clogging of ink nozzles and the like.