Chalk Resistant Paint Characteristics
Many people take paint for granted. They feel that it is a simple product which requires little understanding or training to work with. This is a misconception. Paints are highly sophisticated products. There are many, many different types all with specific formulations. Most paint manufacturers have chemists with PhD's that constantly work with the ingredients of paint in an effort to improve them. The chemistry of paint is not as simple as you or I might think. In fact, some paint formulas are highly guarded secrets.
The paints that you or I use on our houses naturally breakdown. The sun, water, chemicals found in rain water, etc. can cause paint to deteriorate. It is a natural process, as many objects exposed to the elements naturally deteriorate. Because of this, it becomes a challenge to locate, purchase and apply a paint which will not readily breakdown. In order to accomplish this, I feel it would be beneficial for you to understand what characteristics make paint long lasting and chalk resistant.
Most paints are made up of three primary ingredients. These ingredients are pigments, resins, and vehicle. Some individuals prefer to express the vehicle as a combination of two ingredients, solvents and additives.
The pigments are the ingredients which give paint its hiding ability. They also give it its color. A paint without pigment would be very similar to varnish or urethane, basically it would be clear. Pigments can also help to block the corrosive effects of liquids or vapors. They can also be formulated to minimize the effects of ultraviolet radiation (the sun's rays).
Resins for the most part are the most important ingredient of paint. These materials give the paint its ability to 'stick or adhere' to things. The resins also surround the pigments and enable them to stick together as well. Remember, for the most part, resins are formulated to be clear, so you can't really see them. That is why they can surround the pigment and give a uniform color or appearance when dry. The resins can be formulated from many different compounds. Oil based paints have alkyd resins. Latex paints have acrylic resins. Epoxy paints have epoxy resins. So, as you can see, there are different resins, all with different levels of quality. For the most part, resins are the most expensive ingredient in paint. So, if you were a paint manufacturer and you wanted to make more money, what would be the first ingredient that you would try to minimize??? Are you starting to get the picture?
The vehicle is that part of the paint which enables it to be a liquid. If paints didn't have vehicle, they would be solid chunks in the paint can. How would you apply them? Paint manufacturers figured this out a long time ago. They knew that they wouldn't sell much paint if people couldn't use them. For the most part, the vehicle in paint evaporates shortly after you apply paint. This part of the vehicle is called a solvent. The solids (pigments, resins, additives) are left behind on the object you painted. Different paints have different solvents. Oil based paints usually have mineral spirits or turpentine as their solvent. Latex paints consider water as their solvent. Some paints have alcohol as a solvent. The solvents in most oil based paints are considered to be volatile organic compounds (hydro-carbons). These compounds cause air pollution when they evaporate. In liquid form (paint thinner or mineral spirits) they can pollute soil or water. Some states limit the use of these compounds in paint. In the future, it may be almost impossible to purchase 'oil' based paints. Paint manufacturers are responding to this challenge. They are attempting to formulate latex or acrylic paints that have the same durability as oil paints.