More to Paint than Meets the Eye

For thousands of years, humans have used paints for decorative purposes. Whether used to adorn the walls of caves, pottery, or the human body, paint has a long and colorful history.

While today's paints are complex chemical formulations, paints and other coatings continue to serve both decorative and protective purposes. They provide color, as well as a barrier to rain and other elements.

The process of preparing and painting a surface is not complicated, but specific principles must be adhered to. The surface must be clean and free of any loose particles for proper adhesion. The coating must be applied to a specific thickness and under specific conditions in order to properly cure and achieve maximum durability. The specifics will vary from coating to coating.

Among the types of coatings we apply are: paints (both latex and alkyd), elastomerics, water repellents and sealers, stains, varnishes, and polyurethanes.

Paints are the most common type of coating; therefore, most of the information contained in this booklet pertains to paint. Paints are composed of four ingredients:
-resin
-solvent
-pigment
-modifiers

The type and quantity of the resin in a paint will determine its durability. For example, vinyl resins are less durable than acrylic resins. Both are used in latex paints.

The solvent is the liquid in which the resins and other ingredients are suspended. In essence, evaporation of the solvent is what causes the paint film to dry. Water is the solvent for latex paints, while petroleum distillates are the solvent used for alkyd paints.

Pigments impart color to the paint. Modifiers are used to give the paint specific application or curing characteristics. For example, modifiers are used to make a paint more brushable or to improve its leveling characteristics.

Important Factors

While color is often the consumer's primary concern, the other ingredients in the paint can-- particularly the type of resin and the type of solvent-- are important considerations.

The surface being painted will determine which type of paint is preferable. Other considerations, such as sensitivity to petroleum solvent fumes, will also impact which types of paint should be used.

Paint colors are often selected from a fan deck or other color chart. While these charts are useful, it should be remembered that the size of the sample might not provide an accurate representation of how the color will look on a wall or the side of a house.

Many other factors, such as furniture, lighting, landscaping, background colors, etc. will contribute to the final appearance of the paint color.

The sheen of the paint film can also have an impact on its appearance, as well as its durability. In general, a higher sheen may look a little lighter than the sample, because of the manner in which the paint film will reflect light.

Higher sheen paints also tend to be more durable. Their finish is harder, making them less prone to scratches and abrasions, as well as more scrubbable.

These general rules apply to both interior and exterior paints. However, because interior and exterior surfaces are exposed to different conditions, other rules apply to coatings formulated for those specific conditions

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