Flexible Mehrschichtisolierstoffe

Technical laminates for the electrical insulation of motors and dry-type transformers

Flexible multilayer insulation materials are used for the electrical insulation of motors and dry-type transformers. They have excellent electrical, mechanical and chemical properties even for high thermal classes.

Flexible multi-layer insulation materials are produced by bonding plastic films with fibre materials such as presspaper, pressboard, non-woven fabrics, woven fabrics or other plastics. The crucial expertise lies in the technology behind the laminating process and the adhesive systems, which we develop and adapt to your requirements as needed.

The combination of the different materials provides both electrical and mechanical protection, while also offering good impregnability. As well as our standard laminates, our product range also features technical laminates that help to improve heat dissipation in the motor construction industry. The use of flexible multi-layer insulation materials increases an motor’s effectiveness and therefore its efficiency, which is a benefit that results from the high dielectric strength of the materials combined with their minimal thickness.

The beneficial properties of technical laminates:

  • Increased dielectric strength with minimal material thickness
  • Improved capacity for folding and punching
  • Protection against harmful influences of oxidation and hydrolysis
  • Protection against damage during processing

Our flexible multi-later insulation materials are produced in accordance with IEC 60626 and guarantee the qualities and characteristic properties required by this standard. Depending on the material combination, these requirements take the form of specific values for different temperature classes and applications.

Our multi-layer insulating materials cover the following thermal classes according to IEC 60085:

  • 130 °C (temperature class B)
  • 155 °C (temperature class F)
  • 180 °C (temperature class H)
  • 200 °C (temperature class N)

Flexible multi-later insulating materials from Krempel

Tried-and-tested applications

  • Layer insulation

  • Slot insulation
  • Slot covers
  • Phase insulation
  • Slot closures
  • Core insulation
  • Insulation cylinders
  • Cast-resin reinforcement

Standard laminates

Mehrschichtisolierstoffe Typ Trivoltherm TF

Our standard TRIVOLTON®, TRIVOLTHERM®, EVITHERM, PHASOFLEX and PHASOTHERM versions are mostly produced with three layers. Due to their symmetrical structure, three-layer laminates have the advantage that the hygroscopic effect of various individual components (pressboard, aramid paper) is reduced and the rolling tendency seen in two-layer laminates is prevented. These multi-layer insulating materials are therefore particularly suitable for automatic processing.


Special laminates

Mehrschichtisolierstoffe Typ Akafol NH

Because some electrical engineering tasks cannot be optimally performed using conventional standard laminates, we offer a wide range of specially developed laminates with very specific properties. Our special laminates are produced from an extremely wide variety of materials and consist of two, three, four or five layers. The selection of the raw materials depends on the intended purpose. The primary material is often one of our standard laminates such as TRIVOLTHERM® N or PHASOTHERM.


We are continually working on the further development of our product range. These developments could be genuine innovations with a chemical basis that differs from the norm, or films that are modified to create economical and technical benefits such as reduced thicknesses, improved thermal conductivity, partial discharge resistance and heat resistance.

Flexible multi-later insulating materials from Krempel

The components

At least one component of our flexible multi-layer insulation materials is a plastic film.

We process:

  • Polyester films (PET films)
  • Polyimide films (PI films, KAPTON films)
  • Polyethylene naphthalate films (PEN films)
  • Polyphenylene sulphide films (PPS films)

With this cellulose-based insulation material, we primarily use our presspaper in accordance with IEC 60641-3-2. 

For high-temperature special applications, we use polyester non-woven fabrics with various densities, thicknesses and surface structures.

We process papers based on aromatic polyamides in accordance with IEC 60819-3-3 and we use NOMEX® aramid papers in both calendered and uncalendered versions.

This mineral material is primarily characterised by its high temperature resistance and excellent resistance to partial discharge. We provide mica-based special laminates for special applications.

Vulcanised fibre is an insulation material that is made from chemically treated cellulose pulp. Special laminates with vulcanised fibre are used where a high rigidity is required.

An additional resin coating smoothens the surface and helps to improve the processing and therefore to increase the efficiency of the production process.

With our laminates, the resin coating is completely cured.

Extract from our product portfolio

Technical laminates for electrical insulation

Thermal class


Product name

Material composition


B 130 °C Trivolton H Presspaper + Film + Pressspaper

Slot insulation,
Slot covers

B 130 °C Trivolton HP Pressspaper + Film  Slot insulation,
Slot covers
B 130 °C Trivolton HPH Film + Pressspaper + Film Slot insulation,
Slot covers
B 130 °C Trivoltherm P Non-woven fabric + Film + Non-woven fabric Slot insulation,
Slot covers
B 130 °C Trivoltherm P2 Non-woven fabric + Film Slot insulation,
Slot covers
F 155 °C Evitherm / Trivoltherm PSW / Trivoltherm TF Coating/Non-woven fabric + Film + Non-woven fabric/Coating Slot insulation,
Slot covers
F 155 °C Trivoltherm N2 Nomex® + Film Slot insulation,
Slot covers
H 155/180 °C Trivoltherm N Nomex® + Film + Nomex® Slot insulation,
Slot covers
F 180 °C Akafol NH 4 Nomex® + Film + Nomex® + Film Slot insulation,
Slot covers
H 200 °C Akafol N3 unk. Nomex® + Kapton® + Nomex® Phase Insulation
H 200 °C Trivoltherm NKN Nomex® + Kapton® + Nomex® Slot insulation,
Slot covers
H 200 °C Trivoltherm NK Nomex® + Kapton® Slot insulation,
Slot covers
C 220 °C Trivoltherm GKG Glass + Kapton® + Glass Intermediate Insulation
C 220 °C Trivoltherm GK Glass + Kapton® Conductor covering


Thomas Keck, Key Account Manager, Global Sales Energy
Contact me
Thomas Keck
Key Account Manager
Global Sales Energy

Contact form