PVC coefficient

Decorative and industrial paints consist of:

• binders / binder,
• pigments,
• solvent,
• rheological additives (wetting, defoaming, thixotropic agent)

 

       

The addition of pigments is to give the appropriate color to the coating or to act as a filler to obtain the correct consistency of the paint.

Most often, pigments perform both functions simultaneously, which are ultimately impossible to separate.

The filling of paints is described by the PVC (Pigment Volume Concentration) coefficient using the formula:

 

where:

Vpigment = sum of pigments volume

Vbinder = volume of a binders (without solvent)

Gloss of a piant can be changed by modyfing the PVC coefficient:

0 – 5 % = clearcoats,
15 – 25 % = high gloss paints,
30 – 40 % = satin/semi-gloss,
40 – 80 % = matt paints.

As PVC increases, so does the paint density and opacity. However, performance properties such as durability, scrubbability, stain resistance and corrosion resistance are reduced.

The higher PVC value also means that it is more difficult in practice to incorporate additional components into the paint.