Precision Slot Die

Slot Die

FACT: The Japanese multilayer ceramic capacitor (MLCC) manufacturer with over 80% of the world’s market share developed their technology using our slot die know-how, and they use only our technology to manufacture their product today.

Workmanship of Yasui Seiki Precision Slot Die

In the past decade, slot die has become one of the most widely used coating methods in the world. While the majority of slot dies on the market require time-consuming bolt adjustments to obtain uniformity, the precision of the Yasui Seiki slot die is due to meticulous in-house machining, to the 1/1000th of a millimeter to guarantee coating accuracy.

The accuracy of slot die coating depends on the precision of the entire coating machine, and Yasui Seiki's dedication to achieving the highest quality coating possible is reflected in everything we make.

Thanks to our extremely high precision machining and rigorous quality testing, Yasui Seiki precision thin lip slot die can now deposit as low as 1 μm wet.

Coordinate Measuring Machine


  • No profile adjustment bolts
  • Machined to 1/1000th of a millimeter precision
  • Profile accuracy/ levelness tolerance: maximum deviation of 2μm across the entire length of the slot die lip. (Based on the most recent slot die inspection report, the maximum deviation was indetectable, in other words, less than 1μm.
  • Patented manifold and lip configuration for extremely uniform coating
  • Exceptional coating tolerance of +/- 2% (majority of the slot dies on the market can only offer +/- 5% tolerance)
  • The system may be used in “On Roll” or “Off Roll” mode to ensure a wide range of coating thicknesses
Slot Die
750mm Slot Die Coater
Slot Die
Slot Die Coating Head
Slot Die
Battery Electrode Coating

Application Examples

Yasui Seiki precision slot die is very useful when a coating method other than MICROGRAVURE™ is necessary. For example, slot die handles thin to thick layers of multilayer ceramic capacitors very well and it does an exceptional job coating lithium-ion battery electrodes.

A few examples of slot die applications:

  • Multilayer Ceramic Capacitors (MLCC)
  • Li-ion battery electrodes
  • Polyimide coating for flexible printed circuit (FPC)
  • Flexible solar panels
  • Inkjet printer photoresist coating
  • Film casting (polyimide, urethane, epoxy, etc.)
  • Nanomedicine
Multilayer Ceramic Capacitors
Flexible PCBs
Flexible PCBs
Solar Panels
Solar Panels


Due to ever changing demands in slot die applications, Yasui Seiki continues to research & develop the best material and the best slot die configurations to support customer needs.

  • Tungsten carbide lip slot die (US Patent D328,943 - 1992)
  • Corrosion-resistant stainless steel slot die
  • Zero gap slot die
  • Stripe coating