Products for multimedia applications are increasingly equipped with wireless charging devices. ELEKTRISOLA's Smartbond OSP18 has been developed to meet the needs of these specific charging systems. This self-bonding litz wire combines excellent bond strength with good windability, fast soldering and very good hot air bonding characteristics.

The hot air bonding process is environmentally preferred over solvent activation with the added benefits of faster coil production speed and potential for process automation. Smartbond`s very high bond strength guarantees consistent coil dimensions and performance attributes. Very thin coils can be produced with Smartbond`s unique construction giving additional space for designers or to help achieve miniaturisation goals.

Technical values of a typical product

Typical Litz wire:

105 x 0.08 mm OSP18

Overal diameter litz wire:

1.05 to 1.15 mm (approx. AWG 18)


10 %

Resoftening temperature Smartbond:

> 130°C


4 sec. at 420°C

Breakdown voltage (non-bonded twist):

1,200 V


18 %

Cut through temperature:


Bond strength (helical coil):

1,700 cN after 180°C hot air bonding

1,900 cN after 210°C hot air bonding

Litz wire diameter:

0.50 mm to 3.50 mm

Base insulation of single wire:

high temperature modified Polyurethane

P180 for temperature class 180°C (H)

Bond coat on litz wire:

modified thermoplastic

Bonding temperature:

> 170°C


UL listed

SGS-data available


         Benefits         Applications
  • excellent bond strengths achieved by hot air bonding
  • coils for energy transmitter and receiver systems in mobile equipment
  • high winding speed
  • wireless power charger
  • solderable without pre-stripping insulation
  • coreless coils in different variations
  • environment-friendly process automation due to elimination of solvents               
  • thin-walled overcoat possible for small coils
  • customized wall thickness available per customer specification  





Standard litz wireServed litz wireSelfbonding litz wireSmartbond
Stability of coil-goodmediumgood
Flexibility / windabilitysoftmore stiffsoftsoft
Bonding process-solventhot airhot air
Mechanical protectionavggoodavggood
Surface and haptic-roughavgsmooth

Second adhesion step

without additional adhesive




            Diameter of litz wire and copper fill factor 



                 Wire = 100%


Litz Wire


Litz Wire






 Copper density in coil  %
 Typical OD %







 Values of litz wire and copper fill factor

105 x 0,08 litz wire copperStandard Litz WireServed Litz WireSelfbonding Litz WireSmartbond
Typical  OD                          %10010910696
Copper density in coil          %1009388112








   Datasheet Smartbond OSP18 for Wireless Charging