CND SHELLAC SDS SAFETY SHEET 2025
Bis-Trimethylbenzoyl Phenylphosphine Oxide (BAPO) is a dual-initiating photoinitiator used in applications like 3D printing and dentistry for curing UV-curable resins,
Trimethylbenzoyl Phenylphosphine Oxide (TPO) is a mono-initiating photoinitiator primarily used in nail gel products.
The main differences are in their chemical structure, resulting in unique properties like BAPO's enhanced curing performance and TPO's toxicity classification.
Key Differences
- Structure:
- BAPO: is a bis-initiator, meaning it has two trimethylbenzoyl groups attached to a central phenylphosphine oxide structure, leading to a double initiation effect.
- TPO: is a mono-initiator with only one trimethylbenzoyl group attached to a diphenylphosphine oxide structure.
- Application:
- BAPO: is used in applications like dental resin polymerization and 3D printing due to its high photoinitiating reactivity and ability to work with both UV and visible light.
- TPO: is primarily used in nail gel and other cosmetic products to cure the material under UV/LED light.
- Performance & Toxicity:
- BAPO: is known for its enhanced performance, providing faster and deeper polymerization compared to TPO.
- TPO: is being phased out of many cosmetics, especially in the EU, as it has been reclassified as a CMR (Carcinogenic, Mutagenic, or Reprotoxic) substance, particularly toxic to reproduction.
- Regulatory Status:
- BAPO: is considered a safer alternative to TPO.
- TPO: is banned or restricted in some cosmetic products and jurisdictions, such as the EU.