Excellent heat resistance, strength and stiffness

Polyamide Resin

Next-generation flame-retardant materials free of halogens and red phosphorus

Materials in the LEONA™ PN seriesuse halogen-free, red-phosphorus-free flame retardants to achieve excellent flame retardance corresponding to the V-0 (0.30 mm) level of the UL94 flame-retardance standard. (Official certification expected in 2025.)


The superior heat resistance of flame-retardant semi-aromatic polyamides has made these resins an increasingly common choice of material in many industrial sectors—particularly for automotive components and electrical and electronic products—because the progress of miniaturization has pushed component densities to higher and higher levels of integration, increasing the temperatures of typical operating environments. At the same time, red-phosphorus-based flame retardants are a common cause of migration problems and have been banned from use in a growing range of electrical and electronic components.

Excellent heat resistance

LEONA™ PN-series resins boast unusually high melting points even relative to other semi-aromatic polyamides, making them highly heat-resistant.
In particular, the heat resistance of PN00B—a material grade featuring 25% content of glass-fiber reinforcers—stands out as extraordinary even among the  LEONA™ PN-series. The figure below compares the thermal-aging properties of PN00B to those of a typical flame-retardant semi-aromatic polyamide material; after aging for 3000 hours at 150°C, the strength of PN00B decreases by just 6% from its initial value, compared to around 40% for the typical material, showing the excellent heat resistance of PN00B.


​PN00B even outperforms typical polyamides with glass-fiber reinforcers. When tested against a typical flame-retardant semi-aromatic polyamide with 45% glass-fiber content—20% higher than PN00B—strength measurements after 1000 hours found that PN00B was over 25 MPa stronger, with the margin projected to expand with further aging. As this result demonstrates, in other families of typical flame-retardant semi-aromatic polyamide materials, the resins themselves exhibit pronounced degradation, and increasing the content of glass-fiber reinforcers does little to address the underlying problem.

Outstanding strength and fluidity

Compared to typical families of flame-retardant semi-aromatic polyamide materials, LEONA™ PN00B exhibits outstanding strength over a broader temperature range than typical high-strength materials—and higher fluidity than typical high-fluidity materials. For details, consult the material data sheets available for download below.

Outstanding electrical properties (high CTI)

In electrical and electronic components design, materials with a higher comparative tracking index (CTI) allow narrower separation between device terminals, thus facilitating miniaturization.

LEONA™ PN00B  boasts a high CTI of 600 V.
Achieving a 600 V CTI (PLC 0) allows shorter surface-routing distances between electrical or electronic components, helping reduce product sizes.

Outstanding blister-suppressing properties

The highly heat-resistant resins in the LEONA™ PN series can prevent the formation of blisters.


In particular, the superior heat resistance of  LEONA™ PN00B allows it to maintain high strength in high-temperature environments. This suppresses the growth of water or air bubbles in the high-temperature environment of reflow ovens (260-290°C), preventing the formation of blisters.


Figure 3 shows measurement results for the heat deflection temperature (HDT, or deflection temperature under loading: DTUL), which is characterized by observing the deformation of a heated test body subjected to constant loading. Over the peak temperature range of conventional reflow-soldering processes (260-290°C, indicated by the red box in the figure), a typical flame-retardant semi-aromatic polyamide deforms rapidly, while  、LEONA™ PN00B exhibits minimal deformation. This shows how the high strength of  LEONA™ PN00B can suppress the growth of water or gas bubbles in high-temperature environments, helping prevent the formation of blisters.