SINOCURE® 250 is a high-performance cationic photoinitiator based on iodonium salt, supplied as a 75% active solution in propylene carbonate. It is specifically designed for UV-curable systems requiring fast cure speed, low yellowing, and excellent depth-of-cure, particularly in pigmented formulations.
SINOCURE® 250
(Cationic Photoinitiator – Iodonium Salt,75% in PC)
● 化学名称：Blend of Iodonium, (4-methylphenyl)[4-(2-methylpropyl) phenyl]-,hexafluorophosphate(1-) (75%) in propylene carbonate (25%);Irgacure 250;Omnirad 250.
● CAS 登录号： 344562-80-7 + 108-32-7
● Chemical Structure：
| 检验项目 (Item) | 指标要求 (Specification) |
| 外观 (Appearance) | Brown or sorrel liquid |
| 纯度/含量 (Assay) | ≥75.0% |
| 纯度 (Purity) | ≥98.0% |
| Isomer | ≤2.0% |
| Chromatic value | 8~10 |
| 粘度 (Viscosity) | 450-500 mm2/s（ 30°C） |
High reactivity – fast cure speed at low concentrations
Low yellowing – minimal discoloration after UV exposure
Excellent depth-of-cure – suitable for thick sections, especially with appropriate sensitizers
Pigmented system compatibility – outstanding performance in highly pigmented coatings and inks
Versatile – effective alone or in combination with photosensitizers (e.g., thioxanthones)
The amount of Sinocure® 250 required for optimum performance should be determined in trials covering a concentration range :
white base coatings 1.5 – 3.0 %
flexo inks 1.5 – 4.0 %
screen inks 1.5 – 3.0 %
overprint varnishes 1.0 – 1.5 %
as supplied, in combination with 0.5 – 0.7 % of a photosensitizer, e.g., thioxanthones.
UV-curable inks and varnishes for paper, metal, wood, and plastic
Flexographic and screen printing inks
White base coatings and pigmented systems
UV adhesives
Thick-section curing applications (with suitable sensitizers)
Performance enhancement: When used in combination with a-hydroxyketone photoinitiators, SINOCURE® 250 provides excellent surface cure at significantly higher line speeds.
Packaging: 25kgs/200kgs drum.
Storage:
Sinocure® 250 is sensitive to visible light and any exposure to sunlight should be avoided. Opened containers should be closed after use to protect the product against light and moisture. In the presence
of certain vinyl ethers, the stability of Sinocure® 250 can be adversely affected if the formulation is exposed to elevated temperatures. Avoid contact with alkaline additives and water.
Subject to appropriate storage under the usual storage and temperature conditions, our products are durable for at least 24 months.
Sinocure® 250 should be handled in accordance with good industrial practice. Further information is provided in the material safety data sheet which is available on request.
