Product Identification
【Product Name】Tetramethylammonium hydroxide 四甲基氢氧化铵
【Synonyms】N,N,N-Trimethylmethanaminium hydroxide；TMAH
【CAS】75-59-2
【Formula】C4H13NO
【Molecular Weight】91.15
【EINECS】200-882-9
【RTECS】PA0875000
【RTECS Class】Other
【Merck】12,9363
【Beilstein/Gmelin】3558708
【Beilstein Reference】4-04-00-00145

Physical and Chemical Properties
【Appearance】Tetramethylammonium hydroxide is a solid in the hydrated form or a colorless liquid with a strong ammonia-like odor.
【Solubility in water】Miscible
【Vapor Pressure】18 (25℃)
【Density】1.016 g/cm3 (25℃)
【Usage】Used as a basic solvent in the development of acidic photoresist in the photolithography process.
【Vapor Density】6.3
【Refractive Index】1.38 (20℃)

First Aid Measures
【Ingestion】Seek medical assistance.
【Inhalation】Move victim to fresh air. Apply artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or inhaled the substance; induce artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult.
【Skin】Remove and isolate contaminated clothing and shoes. Immediately flush with running water for at least 20 minutes. For minor skin contact, avoid sping material on unaffected skin.
【Eyes】Immediately flush with running water for at least 20 minutes.

Handling and Storage
【Storage】Keep in a cool, dry, dark location in a tightly sealed container or cylinder. Keep away from incompatible materials, ignition sources and untrained individuals. Secure and label area. Protect containers/cylinders from physical damage.
【Handling】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.

Hazards Identification
【Ingestion】See Inhalation.
【Inhalation】TOXIC; inhalation, ingestion, or skin contact with material may cause severe injury or death. Effects of contact or inhalation may be delayed.
【Skin】Contact with molten substance may cause severe burns to skin and eyes. See Inhalation.
【Eyes】See Inhalation.
【Hazards】When heated, vapors may form explosive mixtures with air: indoors, outdoors, and sewers explosion hazards. May polymerize explosively when heated or involved in a fire. Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. Runoff may pollute waterways. Substance may be transported in a molten form.
【EC Risk Phrase】R 10 23/25 35 51
【EC Safety Phrase】S 7 26 36/37/39 45
【UN (DOT)】1835

Exposure Controls/Personal Protection
【Personal Protection】

Wear appropriate protective gloves, clothing and ggles.
【Respirators】Wear positive pressure self-contained breathing apparatus (SCBA).

Fire Fighting Measures
【Fire Fighting】Do not extinguish fire unless flow can be stopped. Use water in flooding quantities as fog. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Solid streams of water may be ineffective. Use alcohol foam, dry chemical or carbon dioxide.
【Upper exp. limit】36
【Lower exp. limit】6.7
【Fire Potential】May burn but does not ignite ily.

Accidental Release Measures
【Small spills/leaks】Keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers. Build dikes to contain flow as necessary.

Stability and Reactivity
【Incompatibilities】Avoid contact with strong acids and oxidizing agents. Attacks many plastics and rubber. May react with metallic aluminum and generate hydrogen gas.
【Stability】No data.
【Decomposition】Above the flash point, explosive vapor-air mixtures may be formed.
【Combustion Products】Fire may produce irritating, corrosive and/or toxic gases.

Transport Information
【UN Number】1835
【Hazard Class】8
【Packing Group】II