Improvement of Flame Retardancy of Seat Cushion Materials for Railway Vehicles Using Intumescent Flame Retardant

In order to further improve the flame retardancy of seat materials in railway vehicles, the authors investigated the use of new flame-retardants. During the selection phase of flame retardants, their attention was focused on intumescent flame-retardants. Intumescent flame-retardant expands and produces char foam during the burning process, and the produced char foam plays a role as a protective shield against rapid flame spread. Various test pieces using the flame-retardants were prepared to confirm their characteristics. The results of cone calorimeter fire tests found that insertion of a resin containing intumescent flame-retardants into the existing seat cushions can improve flame retardancy.