SINOCURE® CPTX (1-Chloro-4-propoxythioxanthone) is a highly efficient Norrish Type II (hydrogen-abstracting) photoinitiator belonging to the thioxanthone family. It possesses strong and broad absorption bands in the near-UV and visible spectral regions (absorption peaks at 257 nm, 314 nm, and 389 nm), making it particularly effective for deep curing in thick films, pigmented systems, and UV/UV-LED curable formulations. It features excellent solubility in organic monomers, low volatility, and high yellowing resistance.
SINOCURE® CPTX
(1-Chloro-4-propoxythioxanthone, Norrish Type II Photoinitiator)
Chemical Name: 1-Chloro-4-propoxythioxanthone
CAS No.: 142770-42-1
MF: C16H13ClO2S
MW： 304.79
Molecular structure：
SINOCURE® CPTX (1-Chloro-4-propoxythioxanthone) is a highly efficient Norrish Type II (hydrogen-abstracting) photoinitiator belonging to the thioxanthone family. It possesses strong and broad absorption bands in the near-UV and visible spectral regions (absorption peaks at 257 nm, 314 nm, and 389 nm), making it particularly effective for deep curing in thick films, pigmented systems, and UV/UV-LED curable formulations. It features excellent solubility in organic monomers, low volatility, and high yellowing resistance.
Appearance | Yellow powder |
Assay / Purity | ≥ 98.0% |
Melting Point | 99 – 103 °C |
Volatile (Loss on Drying) | ≤ 0.50% |
Absorption Maxima | 257 nm, 314 nm, 389 nm |
Broad Spectral Absorption: Strong absorption peaks at 257 nm, 314 nm, and 389 nm, matching UV-LED and mercury lamps.
Superior Through-Cure Capability: Excellent curing performance in heavily pigmented formulations and thick coating layers.
High Photocuring Reactivity: Efficient Norrish Type II hydrogen-abstraction mechanism providing fast cure speed.
Good Compatibility & Solubility: Readily soluble in various acrylic monomers, oligomers, and standard organic solvents.
Recommended Systems: Widely applied in offset inks, flexographic inks, screen printing inks, wood coatings, electronic coatings, plastic coatings, overprint varnishes, and optical adhesives.
Synergistic Formulation: Recommended for use in combination with tertiary amine synergists (e.g., amine acrylates, SINOCURE® EDB) to overcome oxygen inhibition and achieve optimal surface hardness and cure conversion.
(in acetonitrile____0.001% ____0.01% _____0.1% _____1%)
● 20kgs/carton
Being kept in dry, clean warehouse with well ventilation.
Avoid exposing to light and heating.
Protecting the product from leakage, rain and insolation during transportation.
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