FACT: The world’s largest battery separator manufacturer in
Japan developed their
coating
technology using our MICROGRAVURE™ technology, and continues to manufacture their separators
exclusively with our technology.
WARNING: MICROGRAVURE™ is a patented technology of Yasui Seiki. Yasui
Seiki's
genuine MICROGRAVURE™ undergoes a multitude of post-production processes that are not publicly
shared. For this reason, Microgravure rolls manufactured by companies other than Yasui Seiki
consistently underperform compared to the genuine Yasui Seiki MICROGRAVURE™.
What is MICROGRAVURE™?
A smaller diameter gravure roll, engraved with cells of varying depths, is designed to
deliver a
specific coating volume. This roll is used in a reverse kiss coating method, where it is
partially submerged in a solution pan. As the roll rotates opposite to the web&rsquols
direction
it
picks up the coating solution in its cells. A flexible doctor blade gently removes any
excess,
ensuring that only the precisely measured solution from the cells is transferred to the web.
Why is MICROGRAVURE™ better than regular gravure?
Enhanced Stability for Thin Coatings: The smaller diameter of the Microgravure
roll provides a much smaller contact area (a), which allows for an exceptionally stable bead of
solution. This stability is critical for achieving thin, uniform, and glossy coatings, as it
prevents variations and disturbances in the coating fluid.
Improved Clarity and Cleanliness: The larger distance between the web and the
roller (b) minimizes streaks and promotes cleaner lines. This increased separation reduces the
likelihood of mechanical interference that can cause imperfections in the coating application.
No Backing Roll Benefits: The absence of a backing roll means there is no
creasing and a smaller contact area, which helps in preventing the spillover of the solution to
the other side of the substrate. This feature is particularly beneficial for sensitive materials
and precision applications.
Versatility with Low Viscosity Solutions : Microgravure is specifically adept
at coating low viscosity solutions. Its design ensures even and consistent application of very
fluid materials without dripping or uneven spread, which can be a challenge with traditional
gravure methods.
Efficiency with Lightweight Cylinder: The lightweight cylinder of the
Microgravure system facilitates faster and easier changeovers. This reduces downtime between
jobs, enhancing productivity and allowing for a more agile production environment.
Smoother Surface with Reverse Coating: Reverse coating, a technique where the
cylinder rotates in the opposite direction to the web, creates shearing forces that result in a
smoother surface finish. This shearing helps to evenly distribute the coating material and
eliminate textural irregularities.
Regular Gravure
MICROGRAVURE™
Large contact area (a) and small web-to-roller (b) distance
Small contact area (a) and larger web-to-roller distance (b)
Exceptional Uniformity: Microgravure™ offers outstanding uniformity with
a
tolerance of ±2%. This precision is critical for applications requiring consistent thickness
across a wide surface area, reducing material waste and ensuring high-quality results.
Versatile Coating Thickness: Capable of coating layers from 0.5 to 80 microns
when wet,
and achieving as thin as 5 nanometers once dry. This range allows for flexibility in
application, from ultra-thin protective layers to more substantial functional coatings,
accommodating a broad spectrum of industrial needs.
Adapts to Various Viscosities: Efficiently coats low viscosity solutions
ranging from 0
to 200 centipoise (cP), and is compatible with both aqueous and solvent-based solutions. This
adaptability makes it suitable for diverse industries, from pharmaceuticals to electronics,
where different material properties are essential.
Wide Range of Substrate Compatibility: Microgravure™ technology is
versatile enough
to coat on a variety of thin substrates including PET (polyethylene terephthalate), PC
(polycarbonate), PP (polypropylene), aluminum, copper, stainless steel, paper, non-woven
materials, porous substrates and fabric. This capability ensures its applicability in various
sectors such as batteries, packaging, electronics, and textiles, where different substrate
characteristics are key to product performance.
What materials do MICROGRAVURE™ come in?
Hard chrome over special steel alloy
Hard chrome over nickel underplate over special steel alloy
Winkote® DLC (diamond like carbon) over special steel alloy
NEW!! Winkote® DLC (diamond like carbon) over stainless steel (SUS304)
NEW!! Hard chrome over stainless steel (SUS304)
Where can I try MICROGRAVURE™?
Yasui Seiki's Coating Service facility in Bloomington, Indiana, MIRWEC Coating, offers coating
trials
using many different size MICROGRAVURE™.
For example, our smallest R2R lab coater, Mini-Labo™ is
equipped
with MICROGRAVURE™.
Yasui Seiki Workmanship
Yasui Seiki MICROGRAVURE™ rolls are custom-made to order. Each roll undergoes numerous manual
finishing procedures that are our trade secrets. Alongside these finishing procedures, all
meticulous physical, mechanical, and chemical tests are manually conducted with extreme care by our
Master MICROGRAVURE™ engineers. Only Yasui Seiki can deliver the full functionality of our
one-of-a-kind MICROGRAVURE™ technology.
Master MICROGRAVURE™ Engineer, Fumio Koizumi
MICROGRAVURE™ Inspection 1
MICROGRAVURE™ Inspection 2
Application Examples
Yasui Seiki MICROGRAVURE™ is the preferred method in Japan for coating multiple
layers in OLED
displays and touch screen components. Our technology is predominantly used in critical electronics,
including smartphones, tablets, computer monitors, and other OLED displays. Remarkably, 95% of the
smartphones sold in the US contain at least one layer coated by one of our MICROGRAVURE™
machines. Over the past five years, MICROGRAVURE™ has demonstrated unparalleled performance in
every layer of Li-ion battery coatings, including anodes, cathodes, and separators. Additionally,
the application of MICROGRAVURE™ is rapidly expanding in industries such as solar cells
(photovoltaics), wearable medical devices, and state-of-the-art optical films.
OPTICAL
0.005 to 0.015 μm AR/ LR coating on optical films
2 to 3 μm hard coating on optical films
14 μm photoresist coating for hologram application
BATTERIES
0.5 to 1 μm carbon nanotube coating on aluminum foils
2 to 4 μm insulation coating on porous separator films
