Nippon Shokubai is one of the world's biggest makers of acrylic acid, the main ingredient of a resin called SAP, which is used in diapers.

The plant produces about 20 percent of the world's SAP and 10 percent of global output of acrylic acid.

Operations at the plant are likely to be halted for a long time and other makers of SAP resins are operating on a full-production footing, leaving little room for back-up production, the Nikkei business daily said on Sunday.

The explosion occurred on Saturday afternoon at an acrylic acid residue tank and the fire spread to another acrylic acid tank and a toluene tank.

Two explosions occurred, killing a 28-year-old fire fighter and injuring 33 people. The fire was put out on Saturday night. (Reporting by Tetsushi Kajimoto; Editing by Robert Birsel)

• A Permanent Economic Emergency