The Paint Basics
Essentially, paint is a mixture of pigment, resin and a carrier. The main, white pigment is said to be the titanium dioxide, and relatively small amounts of other pigments are added by the paint dealer to tint the color. Resin, on the other hand, is what makes paint adhere to a surface. And, the carrier is the evaporative liquid that is usually added to thin the mixture so you can brush or roll it on water for latex paints or a solvent for oil or alkyd paints.
Paint also contains clay or other inert ingredients which are added to adjust the paint’s sheen. It may also contain small amounts of secondary solvents that help gloss, drying characteristics and the like.
Further worth noting is the fact that the amount of quality of every ingredient is what determines the performance and price of paint. Paint with plenty of titanium dioxide, for example, has strong hiding characteristics, and since this pigment is the most expensive ingredient, the paint no doubt costs more. On the other hand, those oil or alkyd paints that use odorless mineral spirits as a carrier are pricier than those with regular solvents. Given this fact, it can be concluded then that price is a good indicator of quality.
Latex Paint of Oil/Alkyd?
The most perplexing question for homeowners when it comes to house painting is “Should we use latex or oil/alkyd?” Well, according to some experts this common confusion is rooted in history. It was noted that for years, solvent paints were favored for trim, woodwork, most exterior and some interior surfaces for the reason that they flow uniformly. Also, many have noticed that these solvent paints have superb leveling characteristics, and adhere well particularly to poorly-prepared or chalky surfaces. They even give a tough, hard-shell finish, and most of the exterior alkyds can be utilized in sub-freezing conditions.
However, such conception has been changed nowadays. The change is in the wind, so to say. The fact is, today both state and federal air-quality laws are clamping down on the use of solvents in oil/alkyd paints. Well, the problem is, a gallon of solvent-based paint contains about two quarts of mineral spirits. It is these solvents actually that evaporate into the air as volatile organic compounds, resulting to air pollution.
In the near future, it is commonly heard that the federal Environment Protection Agency (EPA) is expected to issue certain guidelines to all states, setting minimum standards for the paint formulas. As you may know, there are a number of state regulations these days that align-with or exceed-these standards. And, some of the experts say that solvent paints that comply with these standards don’t really have advantages over the water-based paints. The fact is, they dry slower and are more difficult to apply. They even cost more.
After saying all of these, I think the bottom line is this: the technology has changed so dramatically that the considered best paint option in most situations will be the latex. It may eventually become your only option.
Alkyd-Modified, Vinyl-Acrylic, or Acrylic?
So it is given that the most favored type of paint these days is the latex. Now, latex paints are not all the same. Note that although the first known latex paints were named after their synthetic “latex” rubber base, the synthetic rubber is not used anymore. So, now when you say “latex”, it refers to all water-borne paint. However, within that category, you have three choices: vinyl-acrylic, 100 percent acrylic, and alkyd-modified latex.
So, what is best option?
In the first place, the vinyl-acrylic latex is by far the least costly latex paint. But, this is considered appropriate for most interior walls as well as for shorter-durability exterior walls.
The well-known high performance interior paints on the other hand are 100 percent acrylic. Many have claimed that this kind of latex paint has better color retention, better adhesion, and in better gloss than vinyl-acrylic in the case of the enamels.
Finally, most of the high-quality exterior paints are either 100 percent acrylic or alkyd-modified latex. Both of these types are excellent though. However, if the siding was previously painted with an alkyd or is chalking, considering alkyd-modified latex is a nice move to take. It has been said that the alkyd-modified latex does an excellent job of penetrating and anchoring the coating on a chalky surface. But, many of the manufacturers these days consider the 100 percent acrylic as their best products.