Toray process

A cross-linked polyolefin foam sheet is produced by two methods using chemical cross-linking and by two methods of radiation cross-linking. The two well-established manufacturing processes for polyolefin foams using radiation cross-linking are the Sekisui process and Toray process. The differences between these two manufacturing methods are mainly in the expansion step, which is almost always done separately. However, the... 

In the Toray process, the foamable sheet is expanded as it floats on the surface of molten salts and is heated from the top by infrared lamps. The mol-fen salt mixture consists of potassium nitrate, sodium nitrate, and sodium nitrite. The salt residues from the surface of the foam are blown off by hot air and stripped in water. The Toray process is suitable to produce cross-linked PP foam sheet as well as polyethylene foam sheet. In fact, Toray was the first one to produce commercial PP foam. ... 

For economic reasons, saturated adsorbents and exhausted ion exchangers must be regenerated. Most commonly, saturation and regeneration are performed alternately and intermittently, but equipment can be devised in which these processes are accomplished continuously by countercurrent movement of the solid and fluid streams. Only a few such operations have proved economically feasible. The UOP and Toray processes for liquid adsorption are not true continuous processes but are effectively such. 

A variant of this reaction, known as the Toray process, is used on an industrial scale in Japan to produce caprolactam, a precursor to nylon. Instead of chlorine, nltrosyl chloride is used to form a nitroso compound that the Toray process... 

This process has now been abandoned because, on a 100000 t/y scale, fermentation of L-Lys based on sugars has proven to be superior to the Toray process. 

The Eastman-Kodak process is operated in a similar way to the Amoco process, adding acetaldehyde as an oxidation accelerator. A further variant is the Toray process, which works with paraldehyde as an oxidation accelerator. 

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