Amines
REACH
p-Methylaminophenol sulfate
CAS Number
55-55-0
EC Number
200-237-1
What is p-Methylaminophenol sulfate?
p-Methylaminophenol sulfate (CAS 55-55-0), commercially known as Metol, is a photographic developing agent and reducing compound.
Where is p-Methylaminophenol sulfate used?
- Photographic and radiographic processing: primary electron donor enabling controlled silver halide reduction
- Developer baths for photographic and X-ray film: core component
- Combined with hydroquinone for fine-grain, high-acutance development
- Printing plate and graphic arts workflows: tonal gradation and developer activity control
- Hair dye formulations: coupler or oxidation base in permanent colorant systems
- Document archiving and micrographic film development rely on this compound.
Commercial specifications
- Purity 98% to 99%+
- Kilogram-scale bags through bulk quantities
Other Names (Synonyms)
Bis(4-(methylamino)phenol);sulfuric acid|Metol
What are the physical properties of p-Methylaminophenol sulfate?
Melting Point 260 °C (decomp)
Density 1.577
Appearance White crystalline powder
Color white to faintly beige
Form Powder
Water Solubility 50 g/L (20 ºC)
Refractive Index 1.6510 (estimate)
pH 3.5-4.5 (20°C, 50g/L in H2O)
How is p-Methylaminophenol sulfate classified and handled safely? Learn More
Warning
GHS07· Irritant GHS08· Health Hazard GHS09· Environmental Hazard
Hazard Statements
H302 Harmful if swallowed
H317 May cause an allergic skin reaction
H319 Causes serious eye irritation
H373 May causes damage to organs through prolonged or repeated exposure
H400 Very toxic to aquatic life
H410 Very toxic to aquatic life with long lasting effects
Precautionary Statements
P260 Do not breathe dust/fume/gas/mist/vapours/spray.
P261 Avoid breathing dust/fume/gas/mist/vapours/spray.
P264 Wash … thoroughly after handling.
P270 Do not eat, drink or smoke when using this product.
Which trade and regulatory codes apply to p-Methylaminophenol sulfate?
HS Code 29222990
UN Number 3077
ADR Class 9
Packing Group III
Storage Class 11 - Combustible Solids
WGK (Germany) 3