-
Product Center
-
-
Contact Us
Tel
Tel
+8618142863185
Follow us
Official Accounts
Official Accounts
- Top
Factors Affecting the Curing Performance of Waterborne UV 3C Coatings
Release time:
2026-07-10 23:20
The curing performance of waterborne UV 3C coatings is influenced by a multitude of factors, ranging from pre‑drying conditions and resin architecture to pigment characteristics, photoinitiator selection, and UV‑light source parameters. Any deviation at any stage can result in incomplete curing or degraded coating performance. Compared with solvent‑based UV coatings, the curing process in waterborne systems is more complex, involving both moisture evaporation and photochemical reactions, and is subject to a broader array of influencing variables. A thorough understanding of the underlying mechanisms governing these factors enables informed adjustments in process design and on‑site control, thereby ensuring consistent coating cure quality.
I. Pre-drying Conditions
Pre‑drying is a critical step in the curing process of waterborne UV coatings, and its thoroughness directly affects the performance of subsequent UV curing. Waterborne UV coatings use water as the primary diluent, resulting in a significant moisture content within the coating film. If this moisture is not adequately removed prior to UV irradiation, the residual water will severely impede the progress of the curing reaction.
The drying conditions prior to curing directly affect the curing rate. If drying is insufficient, even extending the UV irradiation time will result in only surface hardening, with the interior remaining uncured. This occurs because, as moisture on the coating surface evaporates rapidly and the surface layer cures quickly, the residual moisture inside struggles to escape, leaving substantial water trapped within the coating and inhibiting further polymerization reactions.
The ambient temperature during UV irradiation also affects the curing outcome. Higher temperatures enhance molecular mobility, leading to more complete curing reactions. Therefore, preheating prior to UV curing helps improve both the curing efficiency and coating adhesion. Properly controlling the temperature and duration of the pre‑baking process to ensure adequate moisture evaporation before UV exposure is a fundamental prerequisite for guaranteeing high‑quality curing.
II. Structure of Waterborne UV-Curable Resins
The molecular structure of waterborne UV-curable resins directly influences the curing rate. The higher the content of unsaturated groups in the resin molecule, the faster the crosslinking reaction and the greater the curing efficiency.
The reactivity of different functional groups varies significantly. The reactivity of these functional groups increases in the following order: vinyl ether, allyl, methacryloyl, and acryloyl. Resins bearing acryloyl groups generally exhibit faster curing rates, as the carbon–carbon double bond of the acryloyl group displays higher reactivity toward free-radical addition reactions than that of the methacryloyl group.
The structure, molecular weight, and functionality distribution of the resin’s molecular chains also influence the crosslinking density and network architecture during curing. When formulating coatings, it is essential to select an appropriate resin system based on the desired performance requirements, striking a balance between cure rate and other coating properties.
III. Pigment Type and Dosage
As non‑photosensitive components, pigments compete with photoinitiators for UV absorption during the UV curing process, thereby affecting curing efficiency. Different pigments exhibit varying absorption and reflection characteristics in the UV spectrum, leading to differing degrees of inhibition of the curing reaction.
Carbon black exhibits strong ultraviolet absorption, which significantly inhibits curing; white pigments, by contrast, have high reflectivity, causing a portion of the UV radiation to be reflected rather than absorbed and utilized by the photoinitiator. In general, the relative strength of pigment–UV absorption follows this order: black, purple, blue, cyan, green, yellow, and red. Dark‑colored systems typically present greater curing challenges than light‑colored ones, warranting closer attention during formulation design and process parameter optimization.
In the formulation of colored waterborne UV coatings, it is necessary to select a photoinitiator whose absorption wavelength matches the pigment’s transmission window, and to appropriately increase the curing energy or extend the curing time to ensure complete cure of the coating.
IV. Properties of Photoinitiators
The performance of the photoinitiator is a critical factor determining whether an aqueous UV‑curable system can polymerize and cure smoothly. The photoinitiator’s absorption wavelength should match the pigment’s transmission window and be close to the dominant emission wavelength of the light source. If there is a mismatch between the photoinitiator’s absorption peak and the light source’s emission peak, the light energy will not be utilized effectively, leading to a significant reduction in curing efficiency.
The compatibility of photoinitiators in aqueous systems is equally important. It is essential to select photoinitiators that exhibit good compatibility with the aqueous medium to prevent their volatilization and loss with water vapor during the pre‑drying stage. The dosage of the photoinitiator must also be optimized: insufficient loading results in low radical yield and incomplete polymerization, while excessive loading may absorb most of the UV radiation, thereby impeding light penetration into the coating.
V. UV Light Source and Curing Parameters
The characteristics of the UV light source and the settings of curing parameters directly affect the curing performance. The absorption peak of the photoinitiator should closely match the dominant wavelength emitted by the light source to ensure efficient utilization of the light energy. Different types of light sources—such as mercury lamps, LED lamps, and gallium lamps—exhibit distinct spectral distributions; therefore, the appropriate light source must be selected to align with the photoinitiator system in the coating formulation.
Irradiation distance and curing time are two interrelated parameters. The closer the irradiation distance, the higher the light intensity reaching the coating surface, resulting in faster curing; conversely, a greater distance leads to slower curing. If the curing time is too short, the coating may not receive sufficient energy, leading to incomplete cure; if it is too long, it could cause resin yellowing or thermal damage to the substrate. In practical production, the optimal combination of curing parameters must be determined through experimentation, taking into account coating thickness, color, and formulation.
VI. Conclusion
The curing performance of waterborne UV‑curable 3C coatings is influenced by a variety of factors, including pre‑drying conditions, resin structure, pigment characteristics, photoinitiator properties, and UV‑light source parameters. The adequacy of pre‑drying determines whether moisture can be thoroughly removed prior to UV curing; the type and concentration of unsaturated groups in the resin affect the rate of the curing reaction; the absorption and reflection characteristics of pigments relative to UV light modulate curing efficiency; the absorption wavelength, compatibility, and dosage of the photoinitiator dictate the efficiency of light‑energy conversion; and the type of light source, irradiation distance, and curing time collectively determine the amount of radiant energy delivered to the coating. These factors are interrelated and must be considered holistically during process design and on‑site control. A thorough understanding of their underlying mechanisms enables targeted adjustments to process parameters in production, ensuring stable and consistent curing performance.
Disclaimer: The above content has been compiled from publicly available sources and is provided for reference only. If any infringement occurs, please contact us, and we will address it promptly.
Bossin Related Product Recommendations – 3C Coatings | ||
General-purpose | ||
Product Model/English Abbreviation | Product Name/Product Type | Product Features |
B-102 | Bisphenol A epoxy acrylate | High hardness, high gloss, chemical resistance, contains 15% TMPTA. |
B-151 | Modified epoxy acrylate | Low halogen, yellowing-resistant, excellent plating performance, and strong adhesion. |
B-165 | Modified epoxy acrylate | Good flexibility and strong adhesion |
B-216 | Aliphatic polyurethane acrylate | Fast curing, high fullness, and excellent toughness. |
B-368 | Aliphatic polyurethane acrylate | Good toughness, excellent leveling, excellent bend resistance, and excellent heat resistance. |
B-574C | Polyester acrylate | Low viscosity, low odor, excellent wettability, suitable for LED UV. |
B-601 | Aromatic polyurethane acrylate | High hardness, scratch resistance, chemical resistance, and excellent cost-effectiveness. |
B-6019 | Special functional group acrylate | Good leveling, excellent wettability, resistant to boiling water, and excellent color dispersion. |
B-609 | Aliphatic polyurethane acrylate | Fast curing, high hardness, scratch resistance, and chemical resistance. |
B-615A | Aliphatic polyurethane acrylate | Fast curing, excellent toughness, wear resistance, and chemical resistance. |
B-619W | Aliphatic polyurethane acrylate | Fast curing, high hardness, excellent toughness, wear resistance, and chemical resistance. |
B-6380N | Special functional group acrylate | Excellent adhesion to plastics, strong hiding power, and improved paint film appearance. |
B-919B | Aliphatic polyurethane acrylate | Fast curing, high hardness, excellent toughness, and superior chemical and wear resistance. |
Matte | ||
Product Model/English Abbreviation | Product Name/Product Type | Product Features |
B-572 | Polyester acrylate | Low viscosity, low odor, excellent wettability, suitable for LED UV. |
B-650A | Aliphatic polyurethane acrylate | Low viscosity, excellent matting effect, fast curing, and good wettability. |
Wearable device | ||
Product Model/English Abbreviation | Product Name/Product Type | Product Features |
B-6211 | Aliphatic polyurethane acrylate | Fast curing, high hardness, scratch-resistant, and free of organotin. |
Hand feel | ||
Product Model/English Abbreviation | Product Name/Product Type | Product Features |
B-328M | Aliphatic polyurethane acrylate | Low gloss, low viscosity, excellent wettability, and a pleasant hand feel. |
B-868 | Organosilicon photocurable resin | Excellent leveling, smooth finish, fast curing, and stain resistance. |
B-868H | Organosilicon photocurable resin | Excellent leveling, smooth finish, fast curing, and stain resistance. |
Large-area spraying | ||
Product Model/English Abbreviation | Product Name/Product Type | Product Features |
B-374 | Aliphatic polyurethane acrylate | Excellent flexibility, good leveling, resistant to abrasion and chemicals, and resistant to yellowing. |
Car interior | ||
Product Model/English Abbreviation | Product Name/Product Type | Product Features |
B-6063 | Special functional group acrylate | High molecular weight, low curing shrinkage |
B-6210 | Aliphatic polyurethane acrylate | Low viscosity, chemical resistance, environmental resistance, and dual photothermal curing |
B-6263 | Special functional group acrylate | Fast curing, high build, boil-resistant, and excellent toughness. |
B-916 | Aliphatic polyurethane acrylate | Low viscosity, solvent resistance, chemical resistance, and steel-wool resistance. |
B-919B | Aliphatic polyurethane acrylate | Fast curing, high hardness, excellent toughness, and superior chemical and wear resistance. |
Resistant to steel wool | ||
Product Model/English Abbreviation | Product Name/Product Type | Product Features |
B-910A2 | Aliphatic polyurethane acrylate | Low viscosity, yellowing resistance, chemical resistance, and steel-wool resistance. |
B-916 | Aliphatic polyurethane acrylate | Low viscosity, solvent resistance, chemical resistance, and steel-wool resistance. |
B-919B | Aliphatic polyurethane acrylate | Fast curing, high hardness, excellent toughness, and superior chemical and wear resistance. |
Oil-resistant pen | ||
Product Model/English Abbreviation | Product Name/Product Type | Product Features |
B-868 | Organosilicon photocurable resin | Excellent leveling, smooth finish, fast curing, and stain resistance. |
B-868H | Organosilicon photocurable resin | Excellent leveling, smooth finish, fast curing, and stain resistance. |
Battery casing | ||
Product Model/English Abbreviation | Product Name/Product Type | Product Features |
B-431 | Cycloaliphatic Specialty Acrylate | Yellowing-resistant, excellent wettability, low viscosity, fast curing |
B-548 | Polyester acrylate | Withstands high temperatures of 250–280°C. |
Solid color paint | ||
Product Model/English Abbreviation | Product Name/Product Type | Product Features |
B-519 | Self-curing polyester acrylate | Self-initiated photopolymerization performance |
B-560 | Polyester acrylate | Fast curing and excellent pigment wetting. |
Yellowing resistance | ||
Product Model/English Abbreviation | Product Name/Product Type | Product Features |
B-151 | Modified epoxy acrylate | Low halogen, yellowing-resistant, excellent plating performance, and strong adhesion. |
B-160D | Modified epoxy acrylate | Good flexibility, yellowing resistance, and excellent adhesion. |
B-216 | Aliphatic polyurethane acrylate | Fast curing, high fullness, and excellent toughness. |
B-296 | Aliphatic polyurethane acrylate | Fast curing, chemical resistance, yellowing resistance, impact resistance |
B-431 | Cycloaliphatic Specialty Acrylate | Yellowing-resistant, excellent wettability, low viscosity, fast curing |
Monomer Recommendation | ||
Product Model/English Abbreviation | Product Name/Product Type | Product Features |
BM3231 (TMPTA) | Trimethylolpropane triacrylate | High crosslink density, high hardness, high gloss, and excellent wear resistance. |
BM3235 (PET3A) | Pentaerythritol triacrylate | Fast curing, high crosslink density, high hardness, and chemical resistance. |
BM3380 (3EO-TMPTA) | Pentaerythritol triacrylate | More flexible and less irritating than TMPTA. |
BM4241 (DiTMPTA-80) | Bis(2,3-dihydroxypropyl) tetraacrylate | High crosslink density, high hardness, chemical and wear resistance, and water resistance. |
BM4242 (Di-TMPTA) | Bis-trimethylolpropane tetraacrylate | High crosslink density, high hardness, chemical and wear resistance, and water resistance. |
BM6261 (DPHA-80) | Dipentaerythritol hexaacrylate | High crosslink density, high hardness, chemical and wear resistance, and water resistance. |
BM6263 (DPHA-90) | Dipentaerythritol hexaacrylate | High crosslink density, high hardness, chemical and wear resistance, and water resistance. |
Share to:
Related News
Fax: +86 20-3437 9190
Address: 8-9 / F,Building B,Pazhou Science and Technology Park, Xingang East Road, Haizhu District, Guangzhou City, Guangdong Province
Follow us
Copyright © Guangdong Bossin Novel Materials Technology Co., Ltd. All rights reserved.
