UV curable solder resist ink is an essential protective material for printed circuit boards (PCB). It forms an insulating protective layer on circuit traces to prevent short circuits, resist chemical corrosion, and improve circuit stability.With the trend toward high-density, fine-line, high-reliability electronic boards, traditional ink formulas face challenges including insufficient adhesion, poor solvent resistance and easy yellowing.Poly(glycidyl methacrylate) (PGMA) has become a popular functional modifier for high-end PCB UV solder resist ink. Weicheng Advanced Material supplies electronic-grade low-chlorine PGMA (Mw 40,000–80,000) specially designed for electronic ink systems.

1. Working Principle of PGMA in UV Solder Resist Ink

PGMA is an acrylic polymer with numerous pendant glycidyl epoxy groups.In UV solder resist formulations:

1. During UV primary curing, acrylate resin forms the main crosslinked network.

2. In the subsequent thermal post-curing stage, reactive epoxy groups on PGMA react with carboxyl groups (-COOH) of alkali-developable resin.

3. Additional chemical crosslinking points are constructed inside the cured film.

The dual curing system (UV photocuring + thermal epoxy crosslinking) significantly improves the compactness of the solder resist coating.

2. Core Performance Benefits of PGMA for PCB Solder Resist UV Ink

2.1 Enhance Adhesion to Copper Substrate

The epoxy groups of PGMA produce strong bonding force with copper surfaces, effectively preventing solder resist peeling, blistering during high-temperature tin spraying, reflow soldering.

2.2 Improve Chemical Resistance & Anti-Soldering Property

Denser crosslinked network strengthens resistance against developer, stripping solution, flux and hot solder. Reduce undercut and ink corrosion during PCB manufacturing.

2.3 Low Yellowing, Stable Insulation Performance

Weicheng electronic-grade PGMA features low hydrolyzable chlorine and low residual GMA monomer. The cured film maintains stable color after long-term thermal aging, suitable for white solder resist and high-reliability electronic circuits. It maintains excellent electrical insulation.

2.4 Optimize Alkali Developing Performance

Reasonable crosslink density avoids incomplete development of fine lines. Balanced developing speed ensures high resolution for ultra-fine circuit PCB.

2.5 Good Compatibility

PGMA shows excellent miscibility with common alkali-soluble acrylic resins, photoinitiators, fillers and pigments. No phase separation, no precipitation in ink storage.

3. Formulation Tips

• Recommended dosage: 3%–8% of total resin system

• Suitable for green solder resist, black solder resist, white UV solder resist ink

• Matches dual-curing UV solder resist system (UV + thermal crosslinking)

4. Why Electronic-Grade PGMA from Weicheng Advanced Material

✅ Strictly controlled hydrolyzable chlorine ≤15 ppm, meets electronic industry requirements

✅ Low residual GMA monomer ≤0.3 wt%, low odor, low yellowing

✅ Customized molecular weight Mw 40,000–80,000 for ink application

✅ Self-produced high-purity GMA raw material, stable batch quality

✅ ISO certified, EU REACH compliant

✅ Complete COA, TDS, MSDS documents for export customs clearance

✅ Technical support for PCB ink formulation debugging

Contact Weicheng Advanced Material (Shandong) Co., Ltd to obtain PGMA samples for your UV solder resist ink research.