Corona Treater
High Performance Ultra High Frequency Corona
Treatment Systems
Corona treatment system is a very
effective way to increase the surface tension of virtually any material.
Surface treatment is required for plastic films/fabrics whose normal
surface tension is not sufficiently high to permit good wetting by flexo
graphic inks.
Corona treatment system increases the surface tension of the fabrics
respective to inks by inducing molecular changes in the surface of the
films. This is done by exposing the air at the material's surface to a
high-voltage electrical discharge - a corona.
Corona discharge treatment at atmospheric pressure for improving
adhesion of various polymer substrate is now standard practice.
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Narrow web treater are mainly used for
extrusion film plant for small to wide web width and low speed.
Benefits :
- Compact simple construction
- Ultra high frequency
- Soft start
- Low maintenance
- Improved costs savings
- Maximum operator safety
- Easy to install
- Accurate output power
- Economical design
- User friendly
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Features :
- High frequency generators are with IGBT construction aluminium
split box type station assembly for light weight and low corrosion.
- Manual lever and led lock mechanism for retraction of assembly.
- Force cooled convertor for longer life.
- Smooth to & fro micrometric air gap adjustment facility.
- Uniform treatment through out the web width.
- Multi segmented electrode.
- Smooth to & fro micrometric air gap adjustment facility.
- Dielectric sleeve of uniform thickness.
- Can immediately switch over to full power, which reduces wastage.
- High voltage side insulator on station for high voltage cable
entry to avoid short circuit problem.
- Force cooled convertor for longer life.
- Fully enclosed treater station.
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Optional value added features :
- Pneumatic operated treater station.
- Zero speed switch to protect silicon sleeve.
- Ozone extraction system efficiently remove ozone and to cool the
electrode.
- Aluminum frame featuring stainless steel enclosure.
- Stainless steel segmented electrode.
- Bare roller system.
- Easy view windows allow clear unobstructed view of corona
discharge.
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Wide web treater are mainly used for extrusion film
plant, lamination plant, slitting machine for high speed application.
Benefits :
- Compact simple construction
- Ultra high frequency
- Soft start
- Maximum operator safety
- Easy to install
- Accurate output power
- Low maintenance
- Economical design
- Improved costs savings
- User friendly
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Features :
- Full range of sizes from 0.5 kw to 10 kw (Single Phase &
Three Phase).
- High frequency generators are with IGBT construction.
- Pneumatic operated treater station using filtered air from 60-120
P.S.I.. Cylinders are controlled by electronic air valve with
switch.
- Can immediately switch over to full power, which reduces wastage.
- Zero speed control avoids damage to web, roller and ceramic
electrode.
- Efficient ozone extraction blower to cool electrode and sleeve.
- Uniform treatment through out the web width.
- Dielectric sleeve of uniform thickness.
Optional value added features :
- Aluminum frame featuring stainless steel enclosure.
- Stainless steel segmented electrode.
- Bare roller system.
- Easy view windows allow clear unobstructed view of corona
discharge PLC based corona treater generator.
- Open design of corona station ensures easy maintenance aluminium
station assembly for light weight and low corrosion.
- Swinging electrode system with pneumatic operation.
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Corona treatment for conductive material :
Eltech metallized treater assembly for
high-speed corona treatment of conductive as well as non-conductive having
smaller widths up to about 500 mm.
These treaters are an extension of suitable to treat conductive as well as
nonconductive substrates such as aluminum foils, metallized films, multi
layer films, paper, labels of various types etc.
General description :
Water-based and UV inks printed on
plastic films and other substrates create a need for the substrate to be
treated prior to printing.
Corona treating is a very effective way to increase the adhesion of
virtually any plastic material. Corona treatment increases the surface
tension of the Sheet / Fabrics receptive to inks by inducing molecular
changes in the surface of the films/sheets.
Conventional method of roll to roll treatment is standard practice, but in
Offset, Sheet type corona treatment is required to increase surface tension
or improve the printability. Some substrates are corona-treated when they
are manufactured. Many of these substrates require a surface energy boost to
match a particular ink or coating. This is done with corona pretreaters on
the press just prior to the coating application point.
PVC, PP, LD, Foam, Flex, metallized polyester, PE, OPP and other high-low
density plastic materials should particularly be Corona treated to enhance
the quality of the final product.
Technical instruction on how to use Surface tension / Wet
ability tester :
Dynes/cm or Newtons/meter :
Dynes/cm or Newtons/meter is the unit of force in the
centimeter-gram-second absolute system, the force which imparts an
acceleration of 1 centimeter per second to a body having a mass of 1 gram.
Dyne Solution :
Dyne solutions have been used to measure wetting and predict adhesive
potential of plastics and coated paperboard. This method is widely used to
test the treatment level of plastic films intended for printing, laminating
and coating. Test results are based on how varying surface tension solutions
react when applied to a non-absorptive surface: If a given solution wets the
surface, its dyne level is lower than the substrate's; if, instead, it
rapidly forms beads, its dyne level exceeds that of the substrate. This
method offers adequate precision and replicability for most capability
studies, materials research and process control.
Qualitative ratings of treatment level or wettability :
| Sr. No. |
Treatment level in Dynes/cm |
Expected quality rating in terms of
print or coating adhesion / anchorite |
| 1 |
Below 32 |
Very poor printing or coating adhesion.
22.05 |
| 2 |
34 |
Poor printing or coating adhesion.
17.25 |
| 3 |
36 |
Fairly good printing or coating
adhesion. 13.80 |
| 4 |
38 |
Good printing or coating adhesion.
10.95 |
| 5 |
40 |
Very good printing or coating adhesion.
08.55 |
| 6 |
42 |
Excellent printing or coating adhesion.
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Corona
Treater
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