Mayer Rod Coater

Mayer Rod Coater is one of the most popular coating methods. It is widely used in both the laboratory and in production coaters to coat a wide variety of products such as adhesives, window film coatings release papers, food packaging laminates, pressure sensitive tapes, fax papers. It is also one of the oldest coating methods. The first use was by Charles Mayer in 1905 and a patent was issued in 1912. It has been in continuous use since then. A Mayer rod coaters is referred by several names all, Mayer Bar, Meyer Bar, Meyer Rod, coating rods, equalizer bars, doctor rods. Although, Mayer rod is the most frequently used name.

The Mayer rod is a stainless steel rod that is wound tightly with stainless steel wire of varying diameter. The rod is used to doctor of the excess coating solution and control the coating weigh. A typical rod is shown in figure 1. The wet thickness after doctoring is controlled by the diameter of the wire used to wind the roll and is approximately .1 times the wire diameter. Rods are available in a wide variety of wire sizes to give a range of coating weights. Table 1 gives the wire sizes that are available and the wet thickness that can be achieved. The dry thickness is determined by the solids concentration of the coating solutions.

The longevity of Mayer rod coating is a result of several improvements in the technology of the rod. Improvements in the fabrication techniques have given improved precision.  Wet coating thickness can be controlled to .1 mils. Several rod types are available to improve precision and to widen the range of coating weight and viscosities that can be coated. Figure 2 shows some of the types that are available. The gapped rod can coat higher viscosities and increased thicknesses. In the threaded rod, the grooves are machined into the roll to eliminate gaps between wires. The smooth rod with no wires is used to smooth the coating after the wire wound rod.

Rods wound with two or three wired are available for thicker coatings. In addition, the wire on the rod can also be coated to enhance performance.  Rods coated with Teflon™ specialty rods are available where streaking and cleaning are a problem. Rods coated with hard nickel and titanium nitride are available to protect against abrasion and lengthen the life of the rod.

The Mayer rod coating stations has two elements to it. A method for applying an excess of coating the web and the Mayer rod to doctor of the excess coating solution. The application can be an immersion method in which the web is immersed in coating pan by back-up roller or a transfer method in which coating transfers coating to the web. .Figure 3 shows some typical configutations.

The range of operating conditions are as follows:
    • Typical operating conditions
    • Viscosity, centipoises    10-1000
    • Thickness, microns    4-80
    • Speed max, fpm    1000
    • Coating accuracy     10%

Advantages of the Mayer rod coater are:
    • Low cost of rods and coating station
    • Ease of coating weight. Change by replacing coating rod
    • Good quality
    • Low set up and product change time and costs

Disadvantages are:
    •  Limited to low viscosity and line speed
    •   Leveling needed for wire groove marks to flow out

Mayer rods are widely used to make laboratory coatings. In this process the sheet to be coated is placed on a hard smooth surface. The Mayer rod is placed on the top of the sheet and coating solution added behind the rod, which is then draw down the sheet to give the desired coating thickness.  Automated drawdown machines are also available
                                                                 Figure 1
                                                                Wire Wound Roll

                                                         Table 2
                                                Rod Selection Guide

                                                                            Figure 2
                                                                        Mayer Rod Types

provided by R. D. Specialties

                                                                                 Table 4
                                                                    Support Station Configurations

provided by R. D. Specialties

Comments

[Linda]

Dear Sir,

Im from BASF Indonesia, would like to purchased Meyer Bar no. 5 for Laboratory. Please send me the information of the Meyer Bar Price of another info.

Thanks,
Linda

[Ed Cohen]

A good source for Mayer Rods is R.D Specialties in Webster New York. The web site is www.rdspecialties.com The email is sales@rdspecialties.com .

[majid]

hi i want to know the best mathod to coat(thicness=10 micron) a web (width=1000mm) with mayer rod

[Doug Krasucki]

Majid,

Please forgive my taking so long to reply to you. Ed Cohen of AIMCAL sent your question on to me. We supply Coating (Mayer) Rods and related equipment. A #4 rod (.004” diameter wire) or an equivalent formed rod can lay down a 10 micron (.0036”) wet film. On your 1000mm web. We can supply a coating head if you need to apply the coating to the web and meter it or we can supply a rod holder and drive if you already have a method to apply the coating to the web.

I have a few questions:

What is the coating? What is the viscosity? Water or solvent based?

The Web -- Paper or film?; how thick? Can you apply an even tension to the web? How fast do you expect to run?

Those questions should be a good start.

Again, I apologize for taking so long to reply.

Best regards,

Doug Krasucki

R.D. Specialties

Ph: 585.265.0220

doug@rdspecialties.com

[Haiping hong]

To whom it may concern,

I would like to have the quotation for the mayer Rod Coater. many thanks for your help.

Haiping

[ADSUL M.S.]

We are manufacturer of boaxially oriented polyester film in India. Wanted mayer bar coating station for inline coating between MDO and TDO
Please suggest suitable coater and mayer rods.

[Syed Iqbal Hussain]

We are coating on substrate I want to know is it posible 25 micron bar lining on the roller which dia 100mm and length have 1500mm Stainless steel.
Plz reply
Thanks
IQBAL

[Robbie LeBaron]

We manufacture mayer rod based coating machines for different companies and they come up to 2 meters wide. We have roll to roll designs and sheet fed designs. These machines can be purchased through www.clearstarcorp.com. We also custom design machines for special applications as well.
If anyone is considering having a rod made or wrapped RD specialties is the way to go. I have used different companies befor but RD specialties does offer the best quality with precise and uniform wraps. It is possible to even have a machine with different size Mayer rods that are removable. I have used the Mayer design to accomplish new application methods with equipment. Formed rods offer a greater advantage than wire wound. Wire wound rods have a tendency to trap residue from the liquids being applied. The residue gets trapped under the mayer wire wraps and come loose later if proper cleaning proceedures are not followed. If you ever break the wire on a wire wound rod you will know quite quickly the other advantage to formed rods. Unfortunately I know of no one who is making formed rods in the diameters that most Mayer application machines require (1.5 inches to 3.0 inches in diameter). If anyone knows of a company who can form a Mayer rod out of quality stainless Steel with these diameters and up to 2 meters long please let me know.

robbie@polymorphlab.com

[BECUE]

I am loking for mayer bar suppliers able to deliver in France. Is RD able to deliver in france? Do you know any suppliers in Europe.

Thanx in advance

[Doug Krasucki]

We can supply Mayer rods to Europe. Please forward rod dimensions and wire size or wire size equivalent. We would be happy to help.
Doug Krasucki, R.D. Specialties.