Genestar', a new proprietary polyamide resin developed by Kuraray (Japan) is another resin to benefit from the shift to lead-free soldering. This synthetic resin, a polyamide copolymer (PA9T) of terephthalic acid and nonane diamine, is highly resistant to heat, with heat resistance up to 300°C (melting point 306°C, glass transition temperature 125 °C).
A key attribute of Genestar is low water absorption of less than 1% compared with 2.6% or higher for competing materials. The chemical constitution of Genestar is half aromatic polyamide from aromatic core and a long hydrocarbon chain. With its novel chemical constitution, the material displays unique performance relative to other heat resistant polyamides. Compared to PA6 or PA66, it has superior heat resistance, dimensional stability and chemical resistance as well as low moisture absorbency and high abrasion resistance. It also has superior injection molding performance with low gas output, low mold deposit, low contaminant, and good injection stability.