Chevron Phillips Chemical Company, one of the leading polyolefin producers, recently unveiled K-Resin® styrene butadiene copolymer (SBC) film grades specifically designed for shrink label applications. According to the company, the new K-Resin® SBC KR52 provides multiple benefits in yield, printability, and blend capability over other shrink film materials. K-Resin® SBC KR52, with a lower density of 1.01 g/cm3 is said to deliver up to a 25% yield advantage over PVC and PETG. The new grade is said to show upto 80% transverse direction (TD) shrinkage characteristic at 100 °C which allows usage in a broad array of shrink label applications.
Further, blending KR52 with crystal polystyrene provides additional cost savings and significantly increases the stiffness of the shrink label. KR52 has been successfully blended with up to 30% crystal polystyrene while maintaining its broad process window and exceptional clarity. These characteristics of KR52 results into real savings relative to PETG and other competitive high shrink SBCs. Moreover, the blends of KR52 and crystal polystyrene is said to offer high gloss and clarity. Also, surface energy retention characteristics of KR52 blends after surface treatment allow for ease in printed formats, says the company.
Lastly, KR52 is also said to suit machine direction oriented roll on, shrink on (ROSO) applications. While these are typically low shrink applications, the high shrink capabilities of KR52 open up new opportunities in this market. Reynolds Packaging KAMA is currently exploring ROSO prospects in drink bottles and expanded polystyrene foam packaging. Films using KR52 are promising in both of these areas.