SILICONE RELEASE AND PRESSURE SENSITIVE ADHESIVES: Designing Adhesives for Optimal Release Performance Ingrid Brase, Pete Walter Label Release Liner Industry Seminar September 2013

AGENDA Introduction and Background Silicone – Adhesive Release Study Case Study Summary September 2013 Label Release Liner Industry Seminar

Introduction Multiple factors influence the choice of both adhesive and release liner End user requirements Converting, die cutting Printing, dispensing, application Adhesive characteristics Liner characteristics Components are impacted by one another Overall objective is to deliver a label that end user can dispense efficiently Release Study: Consider adhesive factors which contribute to release changes: Tackifier chemistry Rubber/Elastomer types Rheology Case Study: application of study results September 2013 Label Release Liner Industry Seminar

STUDY PARAMETERS Evaluation using single UV cured silicone release formulation. Optimization for obtain easy release Evaluation of 10 Hot Melt adhesives of varying chemistries Sample Preparation: Single UV cured silicone formulation, single coating incidence Test adhesives coated to liner via ChemInstruments HLC-100 Facestock 20# DP Bond, laminated in line. September 2013 Label Release Liner Industry Seminar

Test Conditions All release testing done on IMASS ZPE1100W hi/variable speed release tester. Ramped Velocity: 0-2 meters per second, references force at 1200 ipm (0.508 m/s) Constant Speed testing at 1200 ipm. Samples listed A through J lowest to highest based on G” as per Rheometrics RDAIII temperature sweep. September 2013 Label Release Liner Industry Seminar

Rheology plots Highest G” Lowest G” September 2013 Label Release Liner Industry Seminar

ADHESIVES EVALUATED September 2013 Label Release Liner Industry Seminar

Sample ordering based on Loss Modulus G” September 2013 Label Release Liner Industry Seminar

Release force 0.508 m/s ramped velocity test. (1200 ipm value) September 2013 Label Release Liner Industry Seminar

Constant speed release, 1200 ipm September 2013 Label Release Liner Industry Seminar

Release force by G” and Tackifier September 2013 Label Release Liner Industry Seminar

Release force by G” and Polymer September 2013 Label Release Liner Industry Seminar

Ramped Force Separated by Polymer type September 2013 Label Release Liner Industry Seminar

SUMMARY Study looked at holding silicone chemistry constant and evaluating release force of various adhesives Adhesives were characterized by three parameters: rheology, tackifier chemistry and rubber type Looked at release values at constant speed as well as ramped velocity September 2013 Label Release Liner Industry Seminar

Conclusions Data suggest a strong inverse correlation between G” and release force values Lower release force is required for higher G” formulations (“stiffer” adhesives”) Within the samples evaluated There did not seem to be an effect of tackifier chemistry – hydrocarbon or rosin ester Rubber type also was not seen to correlate to release force Release performance requirements need to be considered during adhesive formulation as well as silicone selection So how can this information be applied to adhesive development? September 2013 Label Release Liner Industry Seminar

Case History: Applying study learnings Background: Launched a new freezer grade adhesive Customer reported release issues: too tight for auto-dispensing Approach Apply learnings from the study to modify release New formula: changes to both rubber and tackifier No significant impact on performance (peel/tack) Maintained cold temperature adhesion Release values now within acceptable range September 2013 Label Release Liner Industry Seminar

Rheology : new versus original September 2013 Label Release Liner Industry Seminar

Release Force Charts Original Adhesive Modified Adhesive Release force values at 1200 in/min Original 17.8 grams/in Modified 11.3 grams/in September 2013 Label Release Liner Industry Seminar

Conclusions Data of study suggested a strong inverse correlation between G” and release force values Lower release force is required for higher G” formulations (“stiffer” adhesives”) Release performance requirements need to be considered during adhesive formulation as well as silicone selection Case Study showed how the study findings can be applied Balance performance needs with release requirements September 2013 Label Release Liner Industry Seminar

Acknowledgements Ashwin Bhongir Stephen Shepherd QUESTIONS??? Thank you! September 2013 Label Release Liner Industry Seminar