With the rapid upgrading of high-density PCB, white solder resist ink and high-reliability electronic coating markets, traditional ordinary PGMA often causes coating discoloration, yellowing after thermal aging, which seriously affects product appearance and circuit stability.Low Yellowing Electronic Grade Poly(glycidyl methacrylate) (PGMA) is specially developed for electronic material systems. Weicheng Advanced Material independently optimizes polymerization technology to strictly control impurity content, delivering low hydrolyzable chlorine, low residual monomer PGMA (Mw 40,000–80,000), perfectly matching dual-curing PCB UV solder resist ink.

1. Core Causes of Yellowing for Conventional PGMA

Understanding the source of discoloration is the foundation of low-yellowing product design:

1. High residual GMA monomer: Unreacted glycidyl methacrylate tends to oxidize under heating and UV irradiation, generating chromophoric groups.

2. High hydrolyzable chlorine: Chloride impurities trigger catalytic oxidation during thermal curing and long-term aging, accelerating yellowing.

3. Thermal degradation fragments: Poorly controlled polymerization produces unsaturated impurity structures, causing color shift.

4. Excess initiator residues: Decomposition residues of free radical initiators introduce chromogens.

Our electronic-grade PGMA solves above problems through whole-process raw material control and optimized synthesis process.

2. Key Technical Specifications of Low Yellowing Electronic Grade PGMA

3. Anti-Yellowing Technical Advantages of Weicheng Electronic Grade PGMA

3.1 Ultra-low residual monomer

Adopt optimized post-treatment process to reduce unreacted GMA monomer, minimize oxidation sources during ink curing and thermal aging.

3.2 Strict control of hydrolyzable chlorine

Low-chlorine process route avoids halogen impurities, critical for white solder resist and high-reliability electronic circuits. Prevent continuous yellowing under long-term heat and humidity environment.

3.3 High-purity self-produced GMA raw material

Starting material GMA reaches 99.9% purity. Vertical supply chain eliminates impure raw material pollution sources.

3.4 Stable thermal oxidation resistance

Rigidly controlled polymer side reactions; few unsaturated impurities. The cured film maintains stable color after reflow soldering and aging test.

3.5 Excellent compatibility with electronic ink systems

Good miscibility with alkali-soluble acrylic resin, photoinitiators, pigments and fillers. No flocculation, precipitation during ink storage.

4. Working Mechanism in PCB UV Solder Resist Ink

Low yellowing electronic-grade PGMA carries abundant pendant epoxy groups.

1. UV stage: Acrylate resin forms primary crosslink network;

2. Post thermal curing: Epoxy groups on PGMA react with carboxyl groups of alkali-developable resin;

3. Build dense dual-curing crosslink structure.

Improve copper adhesion, solvent resistance and anti-soldering performance, while avoiding color change of green, black and especially white solder resist.

5. Recommended Formulation & Processing Guidance

• Suggested dosage: 3 wt% ~ 8 wt% of total resin system

• Application system: Dual-curable UV solder resist ink (UV + thermal curing)

• Curing reference: Main UV exposure + post-curing 140–160 ℃

• Storage reminder: Keep PGMA sealed and dry to avoid moisture absorption

6. Main Application Scenarios

✅ High-density PCB UV solder resist ink (green, black, white ink)

✅ High transparent electronic UV protective coatings

✅ Electronic adhesive modifier requiring low yellowing

✅ Thermosetting insulating coatings for electronic components

7. Why Choose Weicheng Low Yellowing Electronic Grade PGMA

✅ Vertical industrial chain, self-produced 99.9% purity GMA monomer

✅ Precisely controlled low hydrolyzable chlorine, low residual monomer

✅ Optimized anti-yellowing polymerization process, stable batch consistency

✅ Complete testing lab equipped with GPC, GC, titration instrument, DSC

✅ ISO certified, EU REACH compliant

✅ Full set of export documents: COA, TDS, MSDS available

✅ Professional technical support for electronic ink formula adjustment

Contact Weicheng Advanced Material (Shandong) Co., Ltd to apply for electronic-grade PGMA samples and carry out aging & yellowing contrast tests.