Mid Loss Laminates That Outrun Their Price Class
Mid-loss laminates paired with low-roughness copper foil match high-cost ultra-low-loss performance at a fraction of the raw panel price.
T288 Delamination Time
Thermal Resistance Duration
The length of time a copper-clad laminate can withstand a constant temperature of two hundred and eighty-eight degrees Celsius before the layers physically separate measures the thermal stability of the substrate resin. A longer T288 delamination time indicates that the board can endure multiple lead-free reflow cycles without structural breakdown. This property is measured using a thermomechanical analyzer that monitors the thickness of the sample until lamination failure occurs.
It is an essential performance metric for selecting materials for high-density, multi-layer assemblies.
Assembly Defect Avoidance
Outgassing of moisture and volatile compounds during hand soldering or reflow can cause the board layers to split. Materials with a high T288 delamination time are less prone to this blistering during manual rework. This resistance ensures the circuit board retains its mechanical integrity during field repair.
Material Selection Strategy
High-temperature resins such as polyimide or filled FR-4 are engineered to resist molecular bond breakdown at extreme temperatures. Selecting materials that offer an extended T288 delamination time prevents internal circuit separation during complex lead-free assembly cycles. Fabricators test representative coupon samples from each material batch to verify that the substrate meets the minimum duration standards defined by the customer or IPC standards.
This validation process ensures that the finished assemblies survive the thermal stress of high-density SMT manufacturing.