Paperboard Substrate Lightfastness Criteria under Accelerated LED Exposure
Substrate lightfastness under retail LED fixtures depends on optical brightener stability, requiring specific 450 nm test criteria to prevent retail chargebacks.
ASTM G155 Modification
Meaning
Standardized weathering protocol adjustments provide the technical framework for exposing nonmetallic materials to xenon arc light under specific moisture conditions. An astm g155 modification occurs when a laboratory alters the filter types and irradiance levels defined in the primary standard to simulate a specific retail or outdoor environment. This adjustment allows manufacturers to test packaging under light intensities that mirror actual store conditions.
The protocol defines the power density of the xenon lamp and the spectral power distribution required for accuracy.
Protocol Adaptation
Variance from the baseline document permits the simulation of indoor lighting environments where uv levels are lower than direct sunlight. This astm g155 modification typically involves using a window glass filter rather than a daylight filter to remove shortwave uv radiation. Contractual agreements for retail goods often specify these changes to ensure that product shelf life matches the expected light exposure.
The adaptation ensures that the energy hitting the sample surface remains within the range of commercially relevant lighting systems.
Compliance Verification
Documentation of the specific irradiance and temperature settings used during the test confirms that the results meet the buyer requirement. A laboratory report detailing the astm g155 modification specifies the xenon arc lamp wattage and the precise black panel temperature maintained throughout the exposure. Without this record, a supplier cannot prove that their material will resist color fade over a six month retail cycle.
Testing Scope
Coverage extends to plastics and coatings used in consumer goods packaging. Any astm g155 modification is limited to the physical parameters of light and heat. The verification step protects the brand from premature package failure in high light environments.