Quality+Environmental Tests
Overview of Package Testing
Focus on quality and environmental testing.
Types of Packaging
Primary Package: Contains the product, in direct contact with it.
Secondary Package: Contains one or more primary packages.
Tertiary Package: Physical distribution package, referred to as the shipper.
Quaternary Package: Unit load (e.g. palletized load) that is stripped and trapped.
Areas of Testing
Quality Testing: Uses standard methods to determine material quality.
Environmental Testing: Subjecting packaging to real-world or simulated environmental conditions.
Shipping and Abuse Testing: Focused on transportation and distribution, to be covered in next week's lecture.
Quality Testing
Utilizes standard machinery and methods to ascertain quality factors like:
Smoothness of materials.
Water vapor transmission rate.
Bond strength between materials (e.g., steel strength).
Questions posed in quality testing include:
How strong are the materials?
What is the quality of the combination of materials?
Environmental Testing
Purpose: To expose the manufactured package to conditions it may encounter in the real world.
Typically uses approved package subjected to:
Real-world conditions.
Simulated conditions (acceleration).
Accelerated Aging:
Involves exposing packages to conditions beyond typical market encounters (high temperature/humidity) to expedite degradation and corrosion testing.
Aims to reduce time before market by providing faster testing results.
Based on chemical kinetics, noting that reaction rates often double with a 10°C rise in temperature ().
Shock and Vibration Testing
Examination of package robustness during shipping, storage, and handling.
Use of sophisticated machinery (vibration tables) to simulate real-world conditions.
Example: 1 hour on a vibration table simulates 100 miles of transport.
Advantages of simulation include:
Reduced testing time.
Uniformity of results across tests.
Real world testing would require logistics but has variable conditions (different roads, truck qualities, etc.).
Testing Standards and Organizations
Various organizations establish testing standards:
American Society for Testing Materials (ASTM)
Technical Association of Pulp and Paper Industries (TAPI)
Flexible Packaging Association
American Boxboard Association
International Safe Transit Association
Example Testing Protocol (TAPI):
Paper products must be conditioned for a minimum of 24 hours at 73 ± 3.5°F and 50% ± 2% relative humidity to ensure uniformity of test results.
Specific Tests for Materials
Paper:
Tensile Strength and Elongation: Measures % elongation and failure point.
Mullen Bar Strength Test: Measures paperboard strength.
Thickness and Opacity Tests.
Plastic:
Tests for gloss, haze, clarity, slip, blocking, impact fatigue, and flex resistance. For permeability, results expressed in cc's per mil per 100 square inches per 24 hours.
MoCon Testing for gases (oxygen, CO2, water vapor).
Cup Method for water vapor transmission: involves weighing a cup over time to determine water loss through film.
Inks and Adhesives:
Testing includes measuring total solids, viscosity, adhesion.
Adhesion Tests:
Scotch Tape Test: Applying and removing tape from graphics to check for ink adherence.
Southern Rub Test: Rubbing a cylinder against a bottle to observe ink residue.
Unknown Materials Identification:
Determine competitor packaging designs or prevent design infringement.
Environmental Conditions for Testing
Controlled Atmospheric Chambers used for environmental testing settings:
Simulate normal storage or extreme environmental conditions.
Utilize accelerated aging to verify shelf life based on the $Q_{10}$ law, where reaction rates double with every 10°C increase in temperature.
Example for shelf life testing:
Test for products with a one-year shelf life at ambient conditions (approx. 25°C) may be accelerated to cut testing time by raising the temperature 10 degrees Celsius to achieve analytical results in less time.
Conclusion
Lecture focused on quality and environmental testing basics.
Upcoming lecture will explore transportation and distribution packaging testing with a guest speaker specializing in that area.