Chromo board or chromosulphate board is a special, multi-layered board that is given a particularly smooth and resistant surface through a combination of chromium sulphate and various chemical processes. It is primarily used in the packaging industry and for high-quality printed products that require good printability and high durability. The cardboard has very good colour and gloss reproduction and is often used for the production of labels, packaging or presentation materials.
The chemical treatment with chromium sulphate ensures that the surface of the paper is not only strong and rigid, but also resistant to moisture and external stresses. The cardboard has a characteristically smooth, sometimes glossy surface that also accurately reproduces fine details and saturated colours. In production, chromo board is generally used as the base material for premium packaging or high-quality business cards, etc. when it is important to offer a high-quality solution.
In the production of chromium sulphate cardboard, the paper pulp is first treated with chromium sulphate and then dried and pressed, which results in the typical properties of this material. The board is easy to process, for example by die-cutting, folding or laminating, is very resistant to bending, splitting and picking and is also easy to score or crease. Due to the chemical treatment, it is also durable and relatively resistant to environmental influences.
However, the production processes and the use of chromium compounds are now controversial from an environmental point of view. Efforts are now being made to replace chromium sulphate board with alternative, more environmentally friendly materials, as chromium compounds can be harmful to health in large quantities. Nevertheless, chromium sulphate board remains in demand in many specialised areas due to its technical properties and aesthetic advantages.
Chromo board can also be used for archiving, as it is highly resistant to light and ageing when produced acid-free.