All you need to know about varnishes and paints

Varnishes and paints are divided into two types: water based and organic solvent based. Water-based paint uses polymer particles (styrene, acrylic) as a binder and organic solvent-based paint uses alkyd resin particles.

Varnishes and paints are divided into two types: water based and organic solvent based. Water-based paint uses polymer particles (styrene, acrylic) as a binder and organic solvent-based paint uses alkyd resin particles. Modern chemistry gives us the opportunity to create hybrid products in which both polymer and alkyd particles can co-exist simultaneously. The current trend in varnishes and paints is moving towards a total shift in this field towards water-based products where the advantages of organically soluble materials will be retained.

The main operational differences between water-based and solvent-based organic solvent-based materials are as follows:

Water-based varnishes and paints:

- More environmentally friendly

- Fast drying time

- Odourless

Organic solvent based alkyd paints and varnishes

- More resistant

- Easy to clean

- Relatively low cost

- Take relatively long to dry

- Have a characteristic odour

A mixture, which consists of materials which do not dissolve into each other, is called dispersion. In more detail: dispersion is liquid which consists of two or more materials which are not soluble in each other. There are two types of dispersion: suspension (solid particles in a liquid; e.g. river sand in water) and emulsion (liquid in liquid, e.g. oil in water).

The different varnishes can stand for water-dispersion or water-based emulsion paints, but you should be aware that these names do not affect the properties of the paint; for example, water colour, gouache and any water-based emulsion paint are water-dispersion paints.

Separately, let's highlight the definition of latex paint. Latex is an elastic material based on rubber, while latex is the obsolete common name for any polymer particle in an aqueous dispersion. Sometimes the two definitions are confused with each other, thinking that latex paint is too elastic. This is incorrect. Latex paint can be based on many different polymers, but you should not think that an aqueous dispersion of polymers will simultaneously be latex paint. Pay attention to what is called acrylic paint, such paints are mostly made from styrene-acrylic polymer which in itself means that it is latex-acrylic.

The main types of paints and varnishes and their purpose:

- Paint is a material that forms an opaque film of a certain colour when it dries. Paint has a wide range of uses for both interior and exterior applications.

 

Specialty paints (enamels) are a subgroup of paints which, due to a special combination of components, form a very tough and thick film (often with a high degree of gloss).

Most of these types of paints are extremely durable and versatile; the same material can be used for both interior and exterior use on any type of surface (wood, mineral and metal surfaces); some can withstand permanent high temperatures.

Varnish is a substance whose main property is to form a transparent, uniform film on the surface - i.e. we can see the surface of the lacquered material clearly and unaltered. The main duty of lacquers is to protect the surface from mechanical damage, and in some cases from atmospheric changes.

Impregnation is one of the specific types of varnishes and paints used on wooden surfaces. It is characterized by the fact that it does not form a film on the surface, but penetrates deep into the painted surface. This gives the wood a certain colour. It must be noted that impregnation uses liquids of different colours but not pigments (solid particles) and the material is less resistant to UV rays.

Antiseptic - has the property of deep penetration, can be colourless as well as differently coloured. The protective components reduce the impact of external harmful factors on the deeper layers of wood. As a rule, antiseptic is not used to cover wood relief and grain (texture).

Varnish: Used to protect wood, it has a low penetration rate and forms a relatively thick and strong protective film.

Primer: A special kind of varnish, the main purpose of which is to strengthen a certain property, there are several basic types of primers:

- Deep penetrating - penetrates deeply into the surface, strengthens, hardens the surface, levels the absorbency of the surface, after which the paint consumption is reduced.

- Adhesive - increases adhesion (bonding) to the surface, allows application of lacquers on hard non-porous surfaces.

- Retarding - evens out the tone of the surface, prevents stains on painted surfaces, evens out the absorbency and reduces paint consumption.

- Anticorrosive - slows and prevents oxidation process in metals.

- Biocidal - contains active additives against moss and fungus.

- Wood preservative - deep penetrating primers with active biocidal additives additionally protect wood from weather conditions, level the absorbency of the surface and reduce varnish consumption.