Sheet products are often used in decorative applications where the surface finish is critical and in order to offer the best protection of this surface, our sheets can be supplied with polycoating.
During the sheet production process, the underside of material often comes into contact with rollers which can cause some slight scratches. This side is known as the ‘B’ side of the sheet and the surface finish is not guaranteed.
The top side though (the ‘A’ side) rarely has any contact during production and is more often than not used as the prime side of the metal. Although stainless steel, aluminium and steel are robust metals, they are susceptible to light scratches which is why we offer a polycoating service for most of our sheets supplied. More often than not, when ordering decorative sheet products from the mill, the material is already polycoated however, there are occasions where non decorative surfaces need the added protection.
The aluminium coating process
Polycoating is a very thin adhesive plastic which is applied to the top surface (‘A’ side) of the sheet with a specific polycoating machine and there is a vast range of polycoatings available.
The sheets are sent along rollers and as they pass underneath the polycoating, it is applied with a relatively uniform pressure leaving no marks or airbubbles.
The type of polycoating required depends very much on the application and it comes in a range of diverse colours, thicknesses and adhesion levels. Care must be taken as well when considering coating suitable for laser cutting. There is polycoating produced specifically for use on laser cutters and even differentiating between CO2 and fibre optic lasers.
If you’re looking to apply coating to thin material, you may not want to use a thick, high adhesive coating as removing it could bend the metal and similarly, if you’re application involves a lot of different manufacturing process before the final product is produced, you may not want a very thin, low tack coating.
Care must also be taken with polycoating to ensure that the adhesive has had enough time to ‘cure’. Once the polycoating is applied, there is a recommended time to leave the material before processing to ensure that the polycoating has adhered. In addition to this, care must be taken to the temperature and humidity of the environment polycoated material is stored as this can affect the adhesion of the coating.
The standard polycoatings that thyssenkrupp Materials (UK) use are:
- 80 micron white
- 50 micron blue
- Laser Coating
We do, however, have access to a large range of other coatings specifically for large projects.
If you have a project that requires specific coating, contact your local branch for more information.