- Benzene, 1,3-diisocyanatomethyl
- Isocyanic acid, methyl-m-phenylene ester
- Methylphenylene isocyanate
- Tolylene isocyanate
A clear colorless to pale yellow liquid with a pungent odor.
Used as a monomer in the preparation of polyurethane foams, elastomers and coatings, as a cross-linking agent for nylon-6, and as a hardener in polyurethane adhesives and finishes.
Registry Numbers and Inventories.
EC Index Number
Carcinogenic Category 3; Very toxic; Irritant; Sensitising; Dangerous for the Environment
Tumorigen; Mutagen; Primary Irritant
Japan ENCS (MITI)
Melting point, °C
12 - 14
Boiling point, °C
Vapor pressure, mmHg
Vapor density (air=1)
Odor Threshold Odor threshold 2.10 ppm
1.22 g/cm3 (20 C)
Hazards and Protection.
Store at toluene isocyanates indoors in unopened containers at 10 to 29 C. Protect from excessive heat and direct sunlight. Protect from contamination with water, alkali, strong bases, or atmospheric moisture.
All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Wear appropriate chemical protective clothing.
Wear positive pressure self-contained breathing apparatus.
Keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers. Build dikes to contain flow as necessary. Attempt to stop leak if without undue personnel hazard. Use water spray to knock-down vapors.
Toluene diisocyanates do not present an explosion hazard. The DOT classifies toluene diisocyanates as materials that may explode from friction, shock, heat, or contamination.
Reaction with aniline may generate enough heat to ignite unreacted portion and surrounding materials Reaction with water liberates carbon dioxide.
Upper exp. limit, %
Lower exp. limit, %
Do not extinguish fire unless flow can be stopped. Use water in flooding quantities as fog. Solid streams of water may be ineffective. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use alcohol foam, dry chemical or carbon dioxide. Use water spray to knock-down vapors.
This chemical is combustible.
Substance will react with water (some violently) releasing flammable, toxic or corrosive gases and runoff. When heated, vapors may form explosive mixtures with air: indoors, outdoors, and sewers explosion hazards. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapors may travel to source of ignition and flash back. Contact with metals may evolve flammable hydrogen gas.
Toxic oxides of nitrogen are produced during combustion of this material.
I-2B, N-2, CP65
Acute exposures may produce headache, insomnia, euphoria, ataxia, anxiety neurosis with depression, or paranoid tendencies.
Inhalation of vapor or aerosol may produce vomiting and abdominal pain. Epigastric and substernal pain may be secondary to the paroxysmal or persistent cough associated with inhalation.
Burning or irritation of the nose and throat, cough, laryngitis, chest pain, and asthmatic syndrome (chemical bronchitis with severe bronchospasm), sensation of oppression or constriction of the chest, bronchitis, emphysema and cor pulmonale may occur.
Irritation and inflammation are common. Dermal absorption is low.
DO NOT INDUCE VOMITING. Corrosive chemicals will destroy the membranes of the mouth, throat, and esophagus and, in addition, have a high risk of being aspirated into the victim's lungs during vomiting which increases the medical problems. If the victim is conscious and not convulsing, give 1 or 2 glasses of water to dilute the chemical and IMMEDIATELY call a hospital or poison control center. IMMEDIATELY transport the victim to a hospital. If the victim is convulsing or unconscious, do not give anything by mouth, ensure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. Transport the victim IMMEDIATELY to a hospital.
IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. IMMEDIATELY call a physician and be prepared to transport the victim to a hospital even if no symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used.
IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. IMMEDIATELY call a hospital or poison control center even if no symptoms (such as redness or irritation) develop. IMMEDIATELY transport the victim to a hospital for treatment after washing the affected areas.
First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.