Gap Fillers - Keratherm

Keratherm Softtherm

Keratherm® and Softtherm® sheets are filled and highly elastic. Their good compression behavior and good forming capabilities guarantee that rather large component differences can be compensated for. They are electrically insulating and possess gradual heat conductivity. Depending on the type, the sheets have varying self-adhesive behaviors. These types of sheets should not be compressed beyond 40% of the original thickness, because this increases the possibility of these pads reverse oiling.

Kerafol® offers two types of Softtherm® sheets. One is based on a fiber glass-reinforced carrier sheet, while the other type contains the fiber glass reinforcement directly in the sheet.

Types 86/200, 86/210, 86/255 and 86/250 have a fiber glass-reinforced carrier sheet with very good thermal characteristics. A Softtherm® application guarantees outstanding compressibility and formability. These Softtherm® types can be provided with an adhesive application on the carrier sheet side. These sheets’ mounting position is determined by the carrier sheet and should always be mounted to the heat sinks or housing. This also guarantees that the formability will work effectively with the electronic components.

Softtherm® sheets 86/202, 86/212, 86/225, 86/300, 86/320, 86/500 and 86/600 are reinforced by fiber glass fabric at thicknesses of 0.5 to 1.0 mm. From a thickness of 1.5 mm, they are also offered without reinforcement. In addition to types 86/202 and 86/212, these sheets can also be offered with an adhesive application as an assembly aid. Other than for those with an adhesive application, for these types of sheets the mounting position need not be specified. Here make sure that the adhesive coating is always applied to the heat sink or the housing.


  • compensates component irregularities
  • optimized thermal transition
  • good compression behavior
  • UL-listed


  • RD-RAM memory model
  • heat pipe thermal solutions
  • automotive engines
  • control units
  • plasma supply panels


  • highly flexible film
  • outstanding flexibility
  • graduated thermal conductivity
  • good electrical insulation
  • high temperature stability

Film Options

  • single-sided adhesive surface
  • single-sided adhesive coating possible
  • can be supplied in sheets or punched
  • wide variety of deliveryforms

Film Types

Material Characteristics
86/200, 86/210lb (low bleeding) Standard
86/255, 86/250 high thermal conductivity, varying levels of hardness
86/300, 86/320 low thermal resistance, best heat dissipation, good dielectric strength
86/500, 86/600 Best thermal behavior
86/202, 86/212 Low Cost
86/225 Low Cost
86/450 Very good thermal and dielectric characteristics, highly suited for automatic placement
86/525 Outstanding thermal conductivity, very good compressibility
86/120 high insulation, very good compressibility, good thermal conductivity.
U 105 and U 200 Silicone Free