Product Identification

Product Name

Tetramethylammonium hydroxide

Synonyms

N,N,N-Trimethylmethanaminium hydroxide
Tetramethylazanium 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 C)

Density

1.016 g/cm3 (25 C)

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 C)

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 spreading 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 goggles.

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 readily.

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