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Heterocyclic Compounds REACH

UV-328

CAS Number
25973-55-1
EC Number
247-384-8
Chemical Formula
C22H29N3O
Molecular Weight
351.5 g/mol
Industries:Personal Care & CosmeticsCoatings, Adhesives, Sealants & ElastomersAutomotivePrinting & PackagingPlastics & Polymers

Description

UV-328 (CAS 25973-55-1 ), also marketed as Tinuvin 328, is a benzotriazole-class UV absorber used to protect organic materials from photodegradation caused by UV radiation. It functions by absorbing UV light in the 300–385 nm range. By dissipating this energy as heat, it prevents color fading, embrittlement, and loss of mechanical performance in finished products. In coatings and industrial paints, it extends the service life of exterior finishes on metal, wood, and plastic substrates. Automotive OEM and refinish coatings rely on it to maintain gloss retention and prevent yellowing in clear coat systems. Plastics processors incorporate it into polyolefins, PVC, and engineering polymers where long-term outdoor durability is a requirement. Adhesives, sealants, and elastomers used in construction and glazing applications also use this stabilizer to prevent surface cracking. It is essential for preventing bond failure under prolonged sun exposure in harsh environments. UV-328 is supplied as a pale yellow to off-white crystalline powder. It is available in technical grade, which is the standard specification for industrial and polymer applications. Packaging typically ranges from 25 kg bags to bulk quantities. Purity specifications are commonly at 99% minimum by HPLC. This high level of purity ensures consistent performance across various manufacturing processes. The product remains a staple for manufacturers requiring reliable UV protection. Contact us for supply of UV-328 Request Quote

Other Names (Synonyms)

2-(2H-Benzotriazol-2-yl)-4,6-ditertpentylphenol | Phenol, 2-(2H-benzotriazol-2-yl)-4,6-bis(1,1-dimethylpropyl)- | Tinuvin 328 | VN99CPK4TI | Phenol, 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentyl- | CHISORB 328 | CYASORB UV 2337 | 2-(2H-Benzotriazol-2-yl)-4,6-bis(1,1-dimethylpropyl)phenol

Key Technical Features

  • High Purity Grade standard
  • Consistent Batch Quality
  • Full Regulatory & REACH Support
  • Global Logistics Network enabled

Physical Properties

Melting Point84 °C
Boiling Point>180 °C
Density0.958 g/cm³
ColorOff-White to Pale Yellow
FormSolid
Vapor Pressure0Pa at 20℃
Log P7.3 at 25℃

Safety & Handling

Warning
GHS08· Health HazardGHS09· Environment

Hazard Statements

H372Causes damage to organs through prolonged or repeated exposure
H373May causes damage to organs through prolonged or repeated exposure
H410Very toxic to aquatic life with long lasting effects
H413May cause long lasting harmful effects to aquatic life

Precautionary Statements

P260Do not breathe dust/fume/gas/mist/vapours/spray.
P264Wash … thoroughly after handling.
P270Do not eat, drink or smoke when using this product.
P273Avoid release to the environment.
P319Get medical advice/attention if you feel unwell.
P391Collect spillage.
P501Dispose of contents/container in accordance with local regulations.

Trade & Regulatory

HS Code2933.99.8290
Storage Class11 - Combustible Solids
WGK (Germany)2