Breaking the Bottleneck of Small Molecule Migration | Reactive Photoinitiator Monomer CAS 16613-04-0 Achieves Large-Scale Application in Food Contact, Medical and Optical Coating Fields

Introduction

With the high-end and safety-oriented evolution of the UV curing industry, traditional small-molecule photoinitiators suffer from migration, odor residue and contact safety risks, limiting their application in high-demand scenarios such as food packaging, medical substrates, optical films and precisie mass production of 2-(4-Benzoyl-3-hydroxyphenoxy)ethyl methacrylate (Con 3D printing resins. Recently, domestic fine chemical enterprises have realized stablAS: 16613-04-0). As a copolymerizable benzophenone derivative photoinitiator monomer, its molecule contains both benzophenone photosensitive groups and polymerizable methacrylate double bonds. Under UV irradiation, it can covalently bond into the cured resin network, fundamentally solving the migration and contamination issue of small-molecule photoinitiators from the molecular structure and providing a new solution for high-end UV formulations.

Product Basic Information

Full Name: 2-(4-Benzoyl-3-hydroxyphenoxy)ethyl methacrylate

CAS No.: 16613-04-0

English Name: 2-(4-Benzoyl-3-hydroxyphenoxy)ethyl 2-methylprop-2-enoate

Molecular Formula: C₁₉H₁₈O₅

Molecular Weight: 326.34

Category: Reactive Hydrogen-Abstraction Photoinitiator Monomer (Copolymerizable Benzophenone Type)

Purity Specification: ≥98% (custom high-purity grades available upon request)

Appearance: Pale yellow to yellow viscous liquid

Core Structural Feature: One end of the molecule is a benzophenone photosensitive group, and the other end carries a polymerizable methacrylate double bond. During curing, the double bond participates in free radical polymerization to anchor the photosensitive skeleton inside the polymer network without free precipitation.

Core Technical Advantages

1.Ultra-low migration and high safety. Different from traditional small-molecule photoinitiators such as 1173 and 184, this product contains polymerizable double bonds that participate in resin crosslinking during UV curing. Hardly any free monomer migrates out after curing. It meets stringent safety regulations for food contact packaging, medical consumables and cosmetic packaging, and greatly reduces contamination risks caused by coating leachables.

2.Hydrogen-abstraction photoinitiation mechanism with excellent surface curing performance. It belongs to the benzophenone hydrogen-abstraction photoinitiation system. When used with tertiary amine co-initiators, it shows good absorption in the 320~365 nm UV band, effectively mitigating oxygen inhibition on the coating surface and improving surface dryness. It is suitable for thick coatings, pigmented systems and high-filler formulations.

3.Excellent resin compatibility and wide formulation adaptability. Featuring aromatic rings and flexible acrylate segments, the molecule exhibits good compatibility with mainstream UV resin systems including acrylate oligomers, reactive diluents, polyurethane acrylates and epoxy acrylates. Precipitation, whitening and delamination rarely occur. It offers a wide formulation loading window without significantly affecting mechanical properties, weather resistance and optical transparency of cured films.

4.Low odor and controllable yellowing potential. Compared with conventional polymeric benzophenone photoinitiators, this monomer adopts mature purification technology with strict control of residual impurities and lower odor. Yellowing of cured films can be well controlled in proper formulations, making it suitable for optical films and transparent coatings sensitive to color change.

5.Multi-functional molecular design for expandable resin modification. In addition to photoinitiation, methacrylate double bonds can undergo copolymerization in resin synthesis. It can be directly added into UV coatings/inks as a photoinitiation auxiliary, or introduced into the resin backbone as a functional monomer to prepare oligomers with built-in photoinitiating sites and simplify downstream formulation systems.

Main Application Fields

✅ Food-contact grade UV inks and overprint varnishes: Flexible packaging, paper-plastic packaging and UV clear coats on food containers, complying with migration limit standards.

✅ UV coatings for medical substrates: UV cured coatings on disposable medical consumables, medical catheters and photosensitive polymer synthesis for optical implant materials.

✅ Optical films and display coatings: PET hard coat films, anti-glare coatings and optical protective films, balancing light transmittance and curing efficiency.

✅ Precision 3D printing photosensitive resins: SLA/DLP UV curing resins to reduce leachables and improve biosecurity of printed parts.

✅ Electronic photosensitive materials: PCB solder mask inks, electronic protective films and UV curable adhesives for FPC flexible substrates.

✅ Adhesives and pressure-sensitive adhesives: UV curable composite adhesives and transparent PSAs, preventing adhesion failure caused by small molecule migration.

✅ High-grade wood and plastic clear coatings: Low-odor eco-friendly UV topcoats for high-end furniture and home appliance shells.

Formulation Tip: This product is a hydrogen-abstraction photoinitiator monomer with limited initiating activity when used alone. It is recommended to formulate with tertiary amine co-initiators to significantly boost curing speed. The recommended dosage varies with resin system, film thickness and UV lamp power, generally ranging from 2~6%.

Industrial Value

The domestic UV curing industry is accelerating import substitution, while high-end low-migration photoinitiating materials have long relied on overseas suppliers. The domestic mass production of CAS 16613-04-0 copolymerizable benzophenone photoinitiator monomer fills the supply chain gap of reactive benzophenone monomers. The product can be applied in high-safety UV systems without complicated post-treatment, helping ink, coating and new material enterprises develop products complying with China GB standards, EU food contact and medical material regulations. It shortens new product validation cycles for downstream customers and cuts raw material costs for high-end UV formulations.

As market demand for eco-friendly, low-migration and low-leaching materials keeps rising, copolymerizable photoinitiator monomers will become an important development direction in the UV curing sector. Samples, COA certificates and SDS safety data sheets are available for this product. Batch supply from lab scale, pilot scale to tonnage level is supported, with technical access open to UV formulation enterprises and new material R&D institutions at home and abroad.

Conclusion

The R&D team will continue optimizing purification processes to further improve product purity and reduce impurity levels. Meanwhile, matched co-initiator compounding solutions will be developed to expand its application in cutting-edge fields such as flexible optical films and bio-based UV resins, continuously supporting the high-quality development of China’s UV curing new material industry.