How EB Curing Solve Compliance Challenges for Adhesives and Coatings?
On June 1, 2026, two mandatory national standards for coatings—GB 30981.1-2025, Limits of Harmful Substances in Coatings—Part 1: Architectural Coatings, and GB 30981.2-2025, Limits of Harmful Substances in Coatings—Part 2: Industrial Coatings—officially came into effect. The new standards comprehensively replace several previous standards covering architectural and industrial coatings, including GB 18581-2020, Limits of Harmful Substances in Wood Coatings, and GB 18582-2020, Limits of Harmful Substances in Wall Coatings for Buildings.
The new standards bring auxiliary materials such as curing agents, thinners, color pastes, and putties under mandatory control for the first time. VOC limits for some solvent-based industrial coatings have been reduced by more than 20%. At the same time, SVOCs (semi-volatile organic compounds) have been incorporated into the mandatory control system for the first time, while the scope of limits for biocides has also been expanded.
These regulatory developments send a clear signal: VOC control is shifting from “end-of-pipe treatment” toward “source substitution.” For adhesive and coating manufacturers, the question is no longer simply “How can we reduce emissions?” but rather “How can we eliminate VOCs at the formulation source?”
1. The VOC Challenge of Traditional Curing Processes
To understand why EB curing can help solve compliance challenges, it is first necessary to understand where VOC emissions come from in traditional curing processes.
Solvent-based thermal curing is one of the major sources of VOC emissions. These processes use large quantities of organic solvents as thinners. After coating, the material must pass through drying ovens that can extend for dozens of meters, where heat is used to evaporate the solvents into the atmosphere. For a medium-sized coating line, annual VOC emissions can reach dozens of tons. Even when end-of-pipe treatment systems such as RTOs are installed, their energy consumption and potential secondary pollution remain significant concerns.
Water-based coatings replace most organic solvents with water, substantially reducing VOC content. However, their drying process still requires considerable thermal energy, and some water-based formulations require small amounts of additives to improve film formation. More importantly, water-based systems generally have slower drying speeds and higher requirements for substrate wettability, which can limit their adaptability to high-speed production lines.
UV curing achieves solvent-free processing, but its formulations must contain photoinitiators, typically at levels of 3%–10%. Photoinitiators themselves and their photolysis products may remain in the coating as small molecular residues after curing, potentially becoming sources of migrants and odor. As the new GB 30981 standards bring auxiliary materials under regulatory control and introduce SVOCs as a new control category, the compliance burden associated with photoinitiators is becoming increasingly important.
2. EB Curing: A Paradigm Shift from “End-of-Pipe Treatment” to “Source Elimination”
The fundamental difference between EB curing and traditional curing technologies lies in their approach to compliance: EB curing does not simply reduce emissions through downstream treatment. Instead, it eliminates the potential source of emissions at the formulation and process levels.
Completely solvent-free.
EB curing formulations do not require organic solvents as thinners. High-energy electron beams directly penetrate the coating and initiate crosslinking and polymerization reactions at room temperature, eliminating the need to heat the material to evaporate solvents. This means the source of VOC generation is removed at its origin.
No photoinitiators required.
The energy source for EB curing is the high-energy electron beam itself. With typical electron beam energies of 80–300 keV, the energy is tens of thousands of times higher than that of UV photons, which are typically around 3–10 eV. This energy is sufficient to directly break chemical bonds and initiate polymerization reactions. As a result, no photoinitiator is required in the formulation. This eliminates, at the source, the potential residue and migration risks associated with photoinitiators and their photolysis products.
Near-zero VOC emissions.
Because EB curing formulations contain neither solvents nor photoinitiators, VOC emissions throughout the EB curing process can approach zero. This characteristic makes EB curing naturally compatible with policies promoting the substitution of low-volatility raw and auxiliary materials. Coating and printing processes using EB curing may therefore qualify for exemptions from certain end-of-pipe treatment requirements while meeting applicable emission standards.
3. Quantitative Verification: The Compliance and Economic Benefits of EB Curing
The compliance advantages of EB curing have been quantitatively demonstrated in practical applications across multiple industries.
3.1 Material Costs: Eliminating the Ongoing Cost of Photoinitiators
Photoinitiators are typically added to UV-curable formulations at levels of 3% to 10%. EB curing requires no photoinitiators, meaning that this single change can reduce material costs by approximately 5% to 10%. For high-volume manufacturers, this level of savings can be substantial.
3.2 Applications in the Adhesive Industry
In the adhesive industry, EB curing is particularly suitable for solvent-free polyurethane adhesives used in flexible packaging lamination.
Traditional solvent-based adhesives require heated drying after coating to remove solvents, followed by a curing or aging period that may last several days after lamination. EB-curable adhesives use high-energy electron beams to directly initiate crosslinking. Curing can be completed online immediately after coating, eliminating both the drying and aging stages and significantly reducing energy consumption.
The cooperation between Mitsui Chemicals and Toray is an industrial example demonstrating this technology pathway and represents one of the promising directions for replacing solvent-based adhesive systems in the flexible packaging industry.
3.3 Simultaneous Improvement in Production Efficiency
EB curing is not limited by the reaction times associated with conventional chemical curing processes. Production line speeds can reach 100–1,000 m/min, significantly higher than those typically achieved with UV curing.
The first domestic EBC electron beam curing smart manufacturing production line in Feixian, Shandong, reportedly requires only 0.005 seconds for curing. EB curing modules use an enclosed structure, which can significantly extend maintenance intervals. Testing by a major manufacturer showed that overall equipment efficiency increased from 82% to 95%, with annual production increasing by approximately 300 tons.
4. From Compliance to Competitiveness: The Strategic Value of EB Curing
Driven by the new GB 30981 standards and policies promoting VOC source substitution, EB curing has evolved from a simple “environmental option” into a strategic asset for manufacturers.
Compliance benefits from avoiding end-of-pipe treatment.
Under policies promoting the substitution of low-volatility raw and auxiliary materials, companies that complete the substitution and maintain stable operation may apply for exemptions from VOC end-of-pipe treatment facilities and measures for collecting and treating fugitive emissions.
For companies adopting EB curing, this can mean not only avoiding the initial investment of millions of RMB in equipment such as RTO systems, but also reducing ongoing operating costs associated with catalyst replacement, activated carbon regeneration, online monitoring, and other environmental management requirements.
A compliance pathway for export markets.
With the EU Packaging and Packaging Waste Regulation (PPWR) entering full implementation in 2026, packaging is required to move toward recyclable-by-design solutions. EB curing can help all-PE and all-PP mono-material structures achieve barrier and mechanical performance closer to that of traditional multilayer packaging while maintaining recyclability.
In food-contact packaging applications, EB curing can also reduce potential migration concerns because it does not require photoinitiators. Under suitable formulations and testing conditions, the number of migration-related test items may be reduced by approximately 60%, potentially shortening certification cycles by more than 50%.
A technological foundation for brand differentiation.
For brands that position safety and sustainability as core values, the combination of solvent-free processing, photoinitiator-free formulations, and near-zero VOC emissions offered by EB curing can provide a differentiated technological advantage that is difficult to replicate through conventional curing processes.
5. Frequently Asked Questions (FAQ)
Q1: Is EB curing suitable for all types of adhesives and coatings?
A1: EB curing is suitable for the majority of radiation-curable adhesive and coating systems. It is particularly effective for resin systems containing unsaturated double bonds, such as polyurethane acrylates, epoxy acrylates, and polyester acrylates.
Traditional solvent-based or water-based systems generally need to be converted to dedicated solvent-free EB-curable formulations. Major adhesive suppliers in China and overseas have already developed mature product lines specifically designed for EB curing. The EB-curable polyurethane adhesive jointly developed by Mitsui Chemicals and Toray is a representative example for flexible packaging lamination.
For existing formulations, it is recommended to conduct small-scale dose-gradient testing to evaluate radiation compatibility and determine the optimal processing window.
Q2: How long is the typical payback period for an EB curing system?
A2: The initial investment for an EB curing unit is typically in the range of RMB 4–7 million, depending on factors such as web width and energy level. For high-volume production lines, the typical payback period is approximately 18–30 months.
The return on investment comes from multiple sources, including eliminating photoinitiator costs and saving approximately 5%–10% in material costs, reducing energy consumption, increasing production line speeds to 100–1,000 m/min, lowering scrap rates, and reducing environmental management and operating costs by potentially avoiding certain end-of-pipe treatment facilities.
EB curing can consume only 1%–10% of the energy required by conventional thermal curing, depending on the specific process and system configuration.
Q3: How long does it take to convert an existing production line to EB curing?
A3: Modern EB curing units use a modular design and can be installed independently after existing coating or printing units without extensive removal or reconstruction of the original equipment.
A typical retrofit project takes approximately 2–4 weeks from on-site evaluation to commissioning, with relatively limited impact on the existing production schedule.
However, it is important to note that EB-curable and UV-curable systems are not necessarily formulation-compatible. Therefore, when retrofitting a production line, the ink or coating formulation generally needs to be switched accordingly.
Conclusion
The implementation of the new GB 30981 standards and the continued promotion of VOC source-substitution policies mark a fundamental shift in the compliance approach of the adhesive and coating industries—from “meeting emission limits” to “eliminating emissions at the source.”
Against this backdrop, EB curing technology, with its inherent characteristics of solvent-free processing, photoinitiator-free formulations, and near-zero VOC emissions, provides manufacturers with a technical pathway for addressing compliance challenges at the formulation source.
EB curing is not merely a tool for responding to environmental regulations. It can also serve as a technological foundation for improving production efficiency, reducing energy and material costs, and establishing differentiated competitiveness as the manufacturing industry moves toward greener production.
