Autoliv is the world's top maker of equipment such as air bags and seat belts, but it has struggled to break the ties between Japanese carmakers and main supplier Takata in a country where the "keiretsu" corporate culture sees businesses closely bound together in relationships cultivated over decades. The ground has shifted, however; a string of Japanese carmakers have ditched Takata's air bag inflators in recent days after U.S. regulators said they used a chemical that they suspect causes the bag to explode with too much force, spraying metal shards into the car.