Adding colour to PVC

Traditionally colour has been added to rigid PVC (PVCu) by using concentrates such as liquid colours, wax dispersions, universal and flexible PVC based masterbatches. The problem is that all these systems introduce additional components into the compound which, depending on circumstances, may present processing difficulties and/or lead to application failures due to plasticiser migration or changes in physical properties in the final product.

Universal and polymer specific masterbatches for adding colour to flexible PVC have been available for many years but they have never worked reliably in rigid PVC.

There are many reasons for this. PVC is a complex material that is highly sensitive to the introduction of additives. For example, a universal masterbatch may be unsuitable in a PVCu because the carrier lubricates the compound. Processors of the material have always had to find just the right grade for their particular process plant and application. Consequently there are literally thousands of PVC formulations on the market with varying amounts of additives and different levels of compounding; all developed to meet specific performance and processing requirements, or both!

Conversely, polymer specific masterbatches for flexible PVC contain plasticisers. Although this does not actually present compatibility problems when used in PVCu, in effect you are adding plasticisers to a polymer chosen specifically for its unplasticised characteristics.

Please click below to view and download data sheets of Vynacol products. The files require Adobe Reader to view and print them; this is a free program and can be downloaded here.

Vynacol datasheet download