Pigments & Colorants
REACH
1,4-benzoquinone
CAS Number
106-51-4
EC Number
203-405-2
Abbreviation
p-BQ
What is 1,4-benzoquinone?
1,4-Benzoquinone (CAS 106-51-4), also known as quinone or p-BQ, is an oxidizing intermediate used in chemical synthesis, dye manufacturing and surface treatment.
Where is 1,4-benzoquinone used?
- Pharmaceutical manufacturing: key intermediate in the synthesis of active compounds, including antifungal and antimalarial agents
- Dye and pigment production: precursor for hydroquinone-based colorants and oxidant in coupling reactions for printing inks and packaging colorants
- Rubber and polymer processing: polymerization inhibitor and crosslinking agent that helps control reaction rates
- Personal care: quinone derivatives serve as intermediates in hair dye chemistry, where controlled oxidation is critical to color development.
Good to know: Sensitive to moisture and light during storage; proper handling is required during transit.
Commercial specifications
- Technical grade is the most common commercial specification
- Higher-purity grades meet pharmaceutical synthesis requirements
- Packaged in fiber drums or sealed containers
Other Names (Synonyms)
Quinone|Para-Quinone|para-benzoquinone|p-quinone|p-BQ|Eldoquin|Cyclohexadiene-1,4-dione|Benzoquinone [UN2587]
What are the physical properties of 1,4-benzoquinone?
Melting Point 115.7 °C
Boiling Point 180 °C
Density 1.318 g/cm³ @ Temp: 20 °C
Flash Point 38°C
Appearance Quinone is a yellow, crystalline material or large yellow, monoclinic prisms. Pungent, irritating odor.
Color Yellow to green
Odor irritant odor
Form Powder
Water Solubility 10 g/L (25 ºC)
Vapor Pressure 0.1 mm Hg ( 25 °C)
Refractive Index n20/D 1.453
pH 4 (1g/l, H2O, 20℃)
Log P 0.1-0.3 at 23℃ and pH4.8-5.3
How is 1,4-benzoquinone classified and handled safely? Learn More
Danger
GHS06· Toxic GHS09· Environmental Hazard GHS07· Irritant GHS08· Health Hazard
Hazard Statements
H301 Toxic if swallowed
H315 Causes skin irritation
H317 May cause an allergic skin reaction
H319 Causes serious eye irritation
Precautionary Statements
P203 Obtain, consult and follow expert instructions for use.
P260 Do not breathe dust/fume/gas/mist/vapours/spray.
P261 Avoid breathing dust/fume/gas/mist/vapours/spray.
P264 Wash … thoroughly after handling.
Which trade and regulatory codes apply to 1,4-benzoquinone?
HS Code 29146900
UN Number 2587
ADR Class 6.1
Packing Group II
Storage Class 4.1B - Flammable solid hazardous materials
WGK (Germany) 3