Toluene diisocyanate (TDI) is an organic compound with the formula CH3C6H3(NCO)2. Two of the six possible isomers are commercially important: 2,4-TDI (CAS: 584-84-9) and 2,6-TDI (CAS: 91-08-7). 2,4-TDI is produced in the pure state, but TDI is often marketed as 80/20 and 65/35 mixtures of the 2,4 and 2,6 isomers respectively. It is produced on a large scale, accounting for 34.1% of the global isocyanate market in 2000, second only to MDI. Approximately 1.4 billion kilograms were produced in 2000.
TDI is commonly used to manufacture.
Flexible foams – used for the fabrication of bedding, furniture, automotive seating, flexible packaging and carpet underlay; this is the largest market application for TDI.
“Foamed-in-place” polyurethane plastics – ranging from soft and sponge-like too hard and porous for use in furniture, packaging, insulation and boat building.
Polyurethane coatings – used on leather, wire, tank linings and masonry.
Elastomers – used to produce adhesives, films and linings, and abrasive wheels and other mechanical items that require abrasion and solvent resistance.
Rigid, “pour-in-place” foams – for use in appliances, and, in smaller amounts, packaging.
Urethane sealants – used in construction applications.
Cast elastomers – for production of articles such as roller blade wheels.