Flexographic UV Ink Formulation Analysis
Date: Mar 25 2025 From: Star Color
Flexographic UV ink is gaining popularity among printing companies due to its unique performance advantages. From packaging printing to label production, flexographic UV ink is becoming the preferred choice. Based on years of experience in the printing industry, this article analyzes the formulation of flexographic UV ink, providing valuable insights for your reference.
1. Core Components of Flexographic UV Ink Formulation
Photoinitiators (3%-8%)Photoinitiators play a crucial role in flexographic UV ink by absorbing ultraviolet energy and triggering the polymerization and curing process of monomers/oligomers. Due to increasingly stringent food safety regulations, benzophenone-based components have been banned in food packaging due to potential migration risks.
Oligomers (40%-60%)Oligomers are one of the key components of flexographic UV ink, with different types imparting distinct properties. Epoxy acrylates provide high hardness, ensuring excellent abrasion and scratch resistance in label applications. Polyester acrylates, on the other hand, are known for their superior flexibility, making them ideal for soft packaging materials.
Reactive Diluents (20%-35%)Reactive diluents help regulate viscosity and promote curing in flexographic UV ink formulations. TPGDA (Tripropylene Glycol Diacrylate) is a widely used cost-effective choice. With the growing focus on environmental sustainability, the adoption of bio-based monomers as eco-friendly alternatives is on the rise.
2. Three Major Technical Challenges in Formulation Design
Viscosity Control (12-25 sec / 25℃, DIN 4 Cup)
Ink viscosity directly impacts print quality. In flexographic printing, high-viscosity ink can lead to dot gain, reducing the clarity and precision of printed patterns. By incorporating appropriate leveling agents, ink flowability can be improved, ensuring uniform ink distribution and minimizing dot gain, thus enhancing print quality.
Adhesion OptimizationFor non-polar substrates such as PE (polyethylene) and PP (polypropylene), ink adhesion is a critical challenge. These substrates have low surface energy, making it difficult for ink to adhere firmly. Common solutions include pre-coating primers or incorporating vinyl chloride copolymers into the ink formulation, typically at ≤5%.
Curing Speed and Energy Consumption BalanceCuring speed and energy consumption must be carefully balanced in flexographic UV ink applications. Under traditional 120W/cm mercury lamps, ink curing time must be ≤0.3 seconds. With the rise of LED curing systems, energy consumption can be reduced by 60%, lowering production costs and enhancing environmental sustainability. However, ink formulations must be adjusted accordingly to ensure fast and effective curing under LED light sources.
3. Regulatory-Driven Formulation Innovations
Environmental regulations worldwide are shaping the formulation of flexographic UV inks. The EU 10/2011 regulation imposes strict limits on migratory substances, while China's GB 9685-2016 standard specifies heavy metal limits for food-contact materials. These regulations drive ink manufacturers to continuously optimize formulations and reduce the use of harmful substances.
4. Industry Applications and Market Trends
Main Application FieldsFlexographic UV ink is widely used across various industries, each with specific formulation requirements.
In food packaging, low migration properties are essential due to direct food contact, and FDA certification is required.
Label printing emphasizes high abrasion resistance and matte effects.
Soft packaging demands excellent fold resistance, with a required fold endurance of >500 cycles.
As industries continue to raise product quality and environmental standards, flexographic UV ink formulations will continue to evolve to better meet diverse application needs.
Zhongzhixing Color has been dedicated to the sustainable development of the printing industry for many years, constantly improving ink formulations and developing more environmentally friendly printing inks. In flexographic UV ink research and development, our continuous innovation has received widespread user acclaim in practical applications. Contact us today to obtain the FDA test report for our flexographic UV ink.
RU
EN
CN
