Latex
Jenny Lee
General Information
Latex paint (a.k.a. acrylic) uses water as a solvent. It is made with a binder that is either acrylic or vinyl acrylic. The binder, titanium dioxide (pigment), limestone (extender), and water are mixed together until they form an emulsion. Contrary to its name, there is no latex rubber in this paint. It dries within 4 hours depending on humidity. When a water-based paint such as latex is applied to a surface, the water evaporates and individual resin particles become closely packed together. The resins then combine to bind the pigment particles to form a flexible film. Latex paint has opacity, as it can completely cover one color with another. During installation, it adheres well on surfaces previously painted with latex or oil-based paints and wooden surfaces. However, it does not adhere well to high-gloss finishes. It is relatively easy to maintain as it can be washed with soap and water.
Environmental Impact
Latex-based paint releases significantly fewer VOCs during the drying process. It has a lower environmental impact than oil paint because cleanup can be done with water instead of chemicals. In addition, it uses water as a solvent rather than petroleum-based solvents. It can be recycled by combining leftovers but may not be made to low-VOC standards so it needs to be done in well-ventilated areas.
The disposal of paint is mandated by law. Latex paint will dry up into a solid piece if left open. It can be spread out to dry and then when hard, disposed of with other trash.
Use in Interior Setting
1. LAN Architecture designed pastel-colored housing utilizing exterior paint.
2. ASKA's Cafe Banacado features various pastel interior paints.
3. Navy blue latex paint adheres well to this wooden vanity.
4. These wooden cabinets are painted blue in this kitchen to provide a pop of color.
5. This wood flooring features a checkered pattern that was painted on.
Interior Trim
When painting an interior trim with latex paint, it is important to select which finish you would like. There are various finishes available such as eggshell, flat, semi-gloss, and high-gloss. For a trim, semi-gloss and high-gloss finishes are typically recommended because it is best for areas that are washed often. Latex-based paint can be applied on top of a primer that is acrylic or oil-based. While painting, it is important to use a synthetic brush because they can hold their shape and stiffness even in large amounts of water.
Testing Organizations:
EPA - https://www.epa.gov/greenerproducts/interior-latex-paint
EMSL Analytical- https://www.emsl.com/Services.aspx?action=list&ServiceCategoryID=17
Relevant standards through ASTM:
D3924 - Specification for Environment for Conditioning and Testing Paint, Varnish, Lacquer, and Related Materials
D5324-16 - Standard Guide for Testing Water-Borne Architectural Coatings Test
D7488 - Standard Test Method for Open Time of Latex Paints
Sources
1. Knowles, E. & Miller, K. (2014) "A Comprehensive Guide for Selecting Interior Finishes."
2. https://home.howstuffworks.com/home-improvement/home-diy/painting/latex-paint.htm
3. https://everythingwhat.com/what-is-latex-paint-made-of
4. https://greenhomeguide.com/know-how/article/selecting-green-paint