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

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

3. 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

4. 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

5. 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

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

7. ADHESIVES EVALUATED September 2013
Label Release Liner Industry Seminar

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

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

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

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

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

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

14. 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

15. 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

16. 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

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

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

19. 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

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