Westlake Plastics Co. and BFGoodrich Co. are joining a movement to supply less-combustible materials for use in semiconductor fabrication clean rooms.
Fire losses have pushed plastics, insurance and semiconductor interests to urgently seek less-flammable polymers in order to minimize potential business-interruption losses. A modern fabrication clean room, or fab, can cost up to $1.5 billion.
Recently, Factory Mutual Research Corp. of Norwood, Mass., added three Westlake polyvinylidene fluorides to its list of sheet materials meeting the stringent limits of protocol FM4910 on fire propagation, smoke damage and corrosion damage. The protocol applies to a clean room's wet benches, tools, ducts and wall and floor coverings.
Insurers owning Factory Mutual's parent provide lead coverage protecting a large portion of the world's semiconductor fabs.
Two of the Westlake PVDFs are homopolymers, one from Kynar 740 resin and the second from Hylar MP-20. The third PVDF is a copolymer from Kynar Flex 2850-00 resin. Westlake extrudes the materials in Lenni, Pa., and compression molds in Mayfield, Pa.
Lenni-based Westlake will make the sheet materials in thicknesses of one-eighth inch to 4 inches, principally for wet benches and other uses, Domenic Sciamanna, Westlake business manager for corrosion materials, said in a telephone interview.
Each material is inherently flame resistant, and all are being marketed as ``low extractable or high-purity materials,'' Sciamanna said. ``Five or six more materials [are] being put through [Factory Mutual tests] in the next few months.''
BFGoodrich's Corzan Industrial Systems unit is introducing a post-chlorinated PVC sheet for making wet benches for fabs.
Developers formulated a white compound that maintains a critical balance of strength, weldability and chemical resistance, Stan Nerderman, Corzan senior marketing manager, said. Corzan has made CPVC for industrial pipe, fittings and sheet for more than three decades.
Richfield, Ohio-based BFGoodrich makes the resins in Louisville, Ky., and has licensed two extruders to use the new material. Compression Polymers Group's Vycom division will extrude sheet in Moosic, Pa., and sister division Compression Polymers will market the product. Menasha Corp. subsidiary Poly Hi Solidur Inc. is climbing a learning curve toward production of the sheet in Scranton, Pa.
Nerderman said July 6 that Corzan CPVC has cleared preliminary screening at Factory Mutual, and he believed it was nearing a listing under FM4910.
In July 1997, Factory Mutual listed two polymers passing FM4910 criteria. They are a modified rigid PVC from Takiron Co. Ltd. of Osaka, Japan, and a flame-retardant polypropylene from Compression Polymers of Moosic. Subsequently, another Takiron material was listed.
In all, four companies have obtained or seek at least 11 listings using five kinds of plastic including flame-retardant PP, PVC, chlorinated PVC, PVDF and ethylene chlorotrifluoroethylene, according to Roger Benson, a Factory Mutual senior loss prevention specialist in Rohnert Park, Calif.
