Coater rollers and coater backing rollers

Coater rollers and coater backing rollers are the core of a finishing line.
They draw a substrate and transfer it from their surfaces to the stock. The surface of a coater roller must therefore be homogeneous, non-porous and adapted to the application requirements.

Various substrates and different methods can be applied to finish the surface of stock.
Paper can be coated with a pigment; adhesive can be transferred to a plastic foil; paint can be applied to steel sheet; and very fine milk powder can even be produced by a special application system.

Paper industry

In the paper-making industry, on-line and off-line paper stock can be finished with a variety of pigment coatings.
The quality grades of the rubber on coater and coater backing rollers must be absolutely homogeneous. The surface must be free from impurities and be processed to a highly smooth finish.

Some application systems use a double roller process. The coater roller draws the pigment and transfers it to the paper. The paper is guided by the coater backing roller. In this case, the coater roller is normally harder than the coater backing roller.

More modern, faster application system normally use only one roller. The pigment is sprayed or applied by a sump between the paper and roller and a blade. When application is very rapid, a curtain coating system must be used.

In principal, a resilient coating roller cover must have excellent mechanical properties. It must be sufficiently “resilient” to avoid any negative impact on the blade control system. It must be resistant to abrasion and cutting to avoid chafing and cutting paper edges (causing microgrooves on the roller surface). And most importantly, it must have good “sheet release”.

Our quality grades:

  • LÜRA 2503 green (90 Shore A / approx. 10 P&J) for double roller process as coater roller.
  • LÜRA 2506 brown (70 Shore A / approx. 70 P&J) for double roller process as coater backing roller with excellent mechanical properties and good sheet release.
  • LÜRA 2506 black (70 Shore A / approx. 70 P&J) for standard coats.
  • LÜRA 2560/3 grey (70 Shore A / approx. 70 P&J) specially developed for high-speed systems, with excellent mechanical properties and extreme sheet release effect. Tears are minimised by a specially developed surface.

Milk rollers

Top quality milk powder for makers of luxury chocolates can only be produced using a traditional and complex production process.

The milk is boiled and concentrated. A milk film is then applied by an application system to an enormous heating cylinder. The thin milk coat is dried and removed by blade. The powder is coarser than normal standard milk powder but it has an excellent taste of milk and has excellent properties for processing in chocolate.

The quality grades of LÜRA 2551 white and LÜRA 2507 bright are mixtures containing raw materials conforming to FDA and are therefore perfectly suited for this type of complex application.