Which is the difference between alkyd and water base paints (latex paint)?

The main distinction is in the composition. The alkyd paint is primarily composed of solvent base raw materials while the water base paint is composed of materials that are compatible with water. Latex paint (or water base paints) has a dry time to touch of one hour and it is able to be cleaned with water. Alkyd paints (or solvent base paints) generally have longer dry time to touch. 

What happens when a water base paint is diluted with water? Does it have some influence on the durability of the final film?

When a water base paint is diluted with water, the components dilutes also, making adhesion, scrub resistance and hiding power be reduced in certain degree. It is important to follow the recommendations provided for the manufacturer about dilution in order to avoid loss of adhesion, covering and low durability due to excesses of water in the dilution. 

What type of cleaners can I use to remove mildew?

Try using a 25% solution of bleach (this equals to one quarter of bleach in three quarts of water). Apply this solution to the area with mildew, let it acts for at least 15 minutes and then rinse the surface perfectly. Avoid adding ammonia or detergents to the bleach solution. If you are going to apply a new coat of paint, we advice you to use Recol® AP-1 together with the paint (see the section Products). Use personal protection equipment when you work with cleaning solutions. 

What kind of paint is recommended to apply on galvanized surfaces?

After the galvanized surface is clean (by chemical cleaning to remove grease or overages from galvanizing process) apply a primer for non ferrous surfaces type Wash Primer, followed by a solvent base paint.  Do not apply solvent base paint directly on the galvanized surface because the resin of the paint reacts with the zinc of the metal causing the paint flakes. 

What is the special characteristic of zinc base products?

Zinc base products provide a moisture-barrier, protecting the surface from corrosion and then extending the metal’s useful life time. 

How do flat, semi-gloss and gloss paints differ in terms of appearance, durability and washability?

Flat type paints hide better the imperfections of the surface. The higher the sheen, better and soother the surface must be to provide a uniform appearance. In terms of washability, present formulations provide you very similar degree of washability in both types of paints; however, gloss and semi-gloss paints are considered a little bit more washable in comparison with completely flat paints. 

Why certain colors, such as red, are more difficult to cover?

The difficulty to cover a previously painted surface is related not only with the color in the base but also with the darkness of the color to apply. The hiding problem when you apply a new paint is more evident when a very light, clear color (such as yellow) is applied on a very dark color (such as red).  Multiple coats of paint are required in these cases. The use of a flat gray paint will help to cover and to accept better the clear color. 

Is it true that dark colored water base paints have longer service life in comparison that light colored water base paints?

Yes, it is possible. Even if all application factors are equals, the durability of the dark colors is seems better in "earth colors" (such as ocher or red colonial) in comparison to light colors that contain a portion of titanium dioxide which contributes, in certain degree, to the “alligatoring” in long term. 

Solvent base paints tend to be brittle with the time. Do water base paints deteriorate in the same way? 

Not. The particles and the resin of the water base paint form a flexible film along the cycle of life of the paint. This film has the ability to expand and to contract with the surface, which helps the paint in its durability time. A solvent base paint forms its film through constant reactions through its cycle o life. These reactions cause in the paint to be brittle with the time, which can result in paint cracking or flaking.

How can I know if an applied paint is solvent or water based?

If the old painting flakes, take a part of this paint and place the edges of the piece between your thumb and index finger; apply pressure on the edges of the piece.  If the piece is flexible and bends easily, it is probable that the painting is latex (base water).  If the piece is hard and brittle, it is probable that the paint is solvent base.  Another method is to damp with denatured alcohol a piece of cotton and to rub the surface of the paint.  If the paint becomes soft or rub offs, it is probable that the paint is water base.  This test with alcohol generally does not affect solvent base paints.

Do acrylic paints "breathe" to allow moisture to pass through? Does this level of “breathability” is reduced with a retouch or second paint coats?

Studies show that the majority of the moisture of water generated from cooking, washing, cleaning, etc., passes through the walls. If the exterior coat captures the moisture and does not allow it to pass, flaking can occur. Moisture vapor passes more easily through water base paintings than solvent base paints. The application of additional coats of paint effectively reduces moisture vapor transmission, due to the increase in the film thickness. Nevertheless, even with several coats of paint, the film of water base paints is more permeable to water vapor in comparison with films of solvent base paints of comparable thickness. 

Why should it be use a 100% acrylic paint in exteriors instead of cheaper vinyl-acrylic paint?

The benefits of using a 100% acrylic paint in exteriors instead of vinyl-acrylic paint are highest durability and resistance to the environmental factors such as moisture, wind, solar rays, etc. As a result, it is not necessary to repaint frequently when you use a 100% acrylic paint. The initial cost of the 100% acrylic paint is translated in more years of service in behalf of the final finish and smaller labor cost by frequent repainted. 

When a solvent base paint is used, how much time is needed before the product is affected by rain or precipitation?

A minimum of 8 hours is the time required, whenever the temperature is above 20°C. The lower the temperature, the longer the period the product needs before being affected by the rain or precipitation.