Isola FR408HR

FR408HR is a proprietary high-performance 230C (DMA) glass transition temperature (Tg) FR-4 system for multilayer Printed Wiring Board (PWB) applications where maximum thermal performance and reliability are required. FR408HR laminate and prepreg products are manufactured with Isola’s patentable high performance multi-functional resin system, reinforced with electrical grade (E-glass) glass fabric. This system delivers a 30% improvement in Z-axis expansion and offers 25% more electrical bandwidth (lower loss) than competitive products in this space. These properties coupled with superior moisture resistance at reflow, result in a product that bridges the gap from both a thermal and electrical perspective. The FR408HR system is also laser fluorescing and UV blocking for maximum compatibility with Automated Optical Inspection (AOI) systems, optical positioning systems and photo-imagable solder mask imaging.


  • High thermal performance – Tg:190C (DSC), 230C (DMA) Base Laminate, Td:360C (TGA@5% wt loss), Low CTE for reliability
  • T260: 60 minutes
  • T288: >30 minutes
  • Lead-free Compatible and RoHS Compliant
  • UV Blocking and AOI Fluorescence
  • Superior Processing, Closest to conventional FR-4 processing of all high speed materials
  • Core Material Standard Availability – Thickness 0.05mm to 0.8mm, available in full size sheet or panel form
  • Prepreg Standard Availability – Roll or panel form, Tooling of prepreg panels available
  • Copper Foil Type Availability – Standard HTE Grade 3, RTF (Reverse Treat Foil), VLP-2 (2 micron)
  • Copper weights – 1/2, 1 and 2 oz (18, 35 and 70 micron) available, Heavier coper available upon request, Thinner copper foil available upon request
  • Glass Fabric Availability – Standard E-glass, Square weave glass fabric available
  • Industry Approvals – IPC-4101C/21 /24 /121 /124 /129, UL- File Number E41625, Qualified to UL’s MCIL Program