Rajesh Srivastava of UFlex spotlights advantages of PU inks
In terms of cost-effectiveness, Srivastava said, modern PU inks are cost-neutral compared to NC and PVC inks when considering factors such as lower GSM coverage and reduced solvent usage.
23 Aug 2025 | By Prabhat Prakash
Rajesh Srivastava says, PU inks are driving the industry shift away from NC inks
Rajesh Srivastava, SVP at inks, adhesives, and coatings for flexible packaging, labels, and offset packaging industry, UFlex, said, "Today, NC (Nitrocellulose) production is concentrated in a few countries, notably China, making supply chains vulnerable to political pressures and trade disruptions. Also, NC production depends on cotton pulp availability and robust logistics, which have been disrupted by strikes, port closures, and extreme weather events.
He added, "The industry is increasingly shifting toward polyurethane (PU)-based inks due to their advantages in regulatory compliance, especially for food packaging applications, and as an alternative to PVC inks, which face growing challenges from evolving regulations."
Srivastava highlighted the performance of PU inks. He said, "They offer excellent resistance to heat, chemicals, and sterilisation processes, are compatible with high-speed printing, enable low ink-to-solvent ratios, and deliver reliability in long print runs. They are also particularly effective for PET-based laminates that require oxygen barrier properties, mechanical strength, and consistent shelf performance."
In terms of cost-effectiveness, Srivastava said, modern PU inks are cost-neutral compared to NC and PVC inks when considering factors such as lower GSM coverage and reduced solvent usage.
Srivastava underscored the importance of regulatory compliance and food safety. He said PU inks meet all major global food safety regulations and are suitable for food packaging applications, and have become the standard for over 80% of leading Indian converters. They also offer a suitable alternative to PVC inks due to evolving regulatory frameworks.
In terms of sustainability, PU inks have lower VOC emissions and reduced solvent consumption, contributing to a smaller environmental footprint. They also support recyclable and sustainable packaging structures.
Today, PU inks are ideal for replacing PVC inks and can be used on various substrates, including PET, BOPP, CPP, nylon, and PE.
The factors contributing to the decline in Nitrocellulose (NC) availability are geopolitical tensions. Many manufacturers are prioritising military-grade NC, with some converting operations entirely away from commercial production.
UFlex Chemicals' Flexglide PU ink series - At a glance
Flexglide NT (toluene-free): This variant offers excellent results on substrates including PET, BOPP, and nylon. It provides low viscosity, reduced solvent consumption, and minimised residual odour, leading to a longer lifespan for cylinders and doctor blades. It supports both dry and extrusion lamination and is compatible with laser-engraved cylinders, optimising production efficiency.
Flexglide NTNK (toluene- and ketone-free): This variant also offers excellent results on substrates including PET, BOPP, and nylon, with similar benefits to the NT variant regarding viscosity, solvent consumption, odour, and cylinder/doctor blade lifespan. It supports both dry and extrusion lamination and is compatible with laser-engraved cylinders.
Flexglide NTNK 6S: This is a pure polyurethane system designed for a wide range of substrates, including PET, BOPP, CPP, nylon, and PE. It delivers high bond strength and durability through sterilisation and pasteurisation processes. Its formulation allows for lower ink deposition and seamless integration with laser-engraved cylinders to drive further efficiency.
CI Flexglide HB: This variant has been specially developed for flexographic printing on heavy-duty laminates that use chemically coated PET. It delivers exceptional lamination bond strength, excellent performance at high speeds, and compatibility with sterilisation processes. Notably, it also supports recyclable and sustainable packaging structures by eliminating the need for PVC and CPP resins.