Flexpack lamination adhesives based on polyurethane technologies are preferred due to their adaptability towards a wide range of multi-ply laminate structures, low odor, superior adhesive properties and excellent transparency, thereby allowing the packaged goods to be clearly visible.
During the last two decades, the flexible packaging industry has seen the majority of innovations toward establishing low-VOC or solvent-free polyurethane adhesive systems to provide a greener touch to our mother earth. Solvent-free adhesives can be 2K (two-component or two-pack) or 1K (mono-component or one-pack) based on prepolymers containing reactive terminal groups either to react with one another or with moisture.
In 2K procedures, the hardener is usually added before machine operation, using a mixing or metering system. Once the hardener has been added, the processability time is limited. The solvent-based lamination adhesives containing organic solvents are more complex because the solvents must be eliminated by evaporation along the lamination line operations. On the contrary, solvent-free lamination adhesives, involving almost negligible volatile matter, have the benefit of being usable at higher line speeds than those containing solvents.
In addition to the advantages of the solvent-free concept, 1K adhesives have the suitability for the user to eliminate the complicated procedures of mixing highly viscous components before application, decreasing machine investments, and controlling errors at the metering and mixing stage.
“As a promoter and believer in the development of sustainable chemistry, Yansefu team not only established advanced mono-component adhesive technologies but also started encouraging its valuable customers and channel partners to augment the use of 1K adhesives. Recently, Yansefu increased its 1K adhesive production towards achieving its commitment in the direction of making greener technologies in India,” said JK Sharma, CEO, Yansefu Inks and Coatings.
“Our state-of-the-art mono-component adhesive removes the hassles of NCO/OH mixing, and is suitable for paper, film and alu foil applications. This is especially suitable for transfer metallization applications. Low viscosity, higher press speed and better thermal resistance properties are making our customers happy,” said Neelakamal Mohapatra, president-R&D, Yansefu Inks and Coatings.