When choosing interior paints, you should immediately pay attention to the composition: it should not contain volatile substances. Paints with harsh odors and the same diluents are not acceptable for homes and offices. Only those that are diluted with water or natural olive oil will do.
What are building paints?
This concept includes a large list of decorative, protective, and special paint materials: paints, varnishes, enamels, primers, powder paints, and fillers.
According to their purpose, they are divided into several groups:
- weatherproof,
- preservative,
- water-resistant,
- heat-resistant,
- special
- and others.
By application area: for external and internal finishing coats on plastered surfaces, untreated concrete and stone, wooden and metal surfaces, rubber, and plastic.
The color of any paint is given by dyes, but the main properties are determined by fillers (sometimes this role is played by pigments), binders, and additional components. Toxic pigments should be noted: lead and zinc greens and crowns (yellow), lead minium (orange), chrome, and manganese oxides (green).
Fillers can be finely dispersed substances: chalk, kaolin, or other stone rocks, they give the coating density, strength, and texture. For interior work is supposed to use non-toxic materials.
Binders are aqueous and non-aqueous solutions that, when dry, form a film that binds pigments, fillers, and the painted surface together. The use of binders releasing toxic substances on the premises is inadmissible.
Additional components include hardeners, drying agents, and plasticizers, and also have restrictions on use for interior coatings.
So, interior paint is a type of construction paint, which has higher hygienic requirements. Now let’s consider the types of interior paints.
Glue paints
Glue paints are basically a ready paste suspension – mixture of pigments, filler (chalk) and water. They are prepared by mixing the suspension with glue before use.
Binders in this composition are aqueous solutions of natural or synthetic adhesives: casein, dextrin (starch-based), polyvinyl acetate and others.
The strength and water resistance of the paint composition determine precisely the binder components. Thus, casein refers to washable coatings, but in the manufacture, to dissolve casein in water requires the use of additives such as lime, soda, aqueous ammonia solution. The process is quite time-consuming, it is easier to use ready-made oil paint for walls, which provides an acceptable water repellent coating.
At home, starch or PVA is used as a binder. Compounds are applied with a brush, on large surfaces – roller or sprayer. Every one to two years, the coating is washed out with water and renewed.
Water-based paints
Water-based paints also include water-dispersion, emulsion and latex paints. One of their biggest advantages is the absence of toxic solvents. If the description says “dispersion latex” or “water-dispersion acrylic binder” – that’s all about it, the water-based paint.
This paint includes about 15 components: binder, pigments, fillers, plasticizers, various functional additives (thickeners, preservatives and others).
Depending on the binder (film-forming agent) compositions are divided into the following:
- latex – with an aqueous emulsion of rubber-like polymers;
- acrylate water emulsion – with acrylate copolymer;
- polyvinyl acetate – PVA with acrylates;
- alkyd
- and a number of others.
It is acrylates that give the best properties to the coating during natural drying. New copolymers of this series and functional additives, development of new artificial latexes allow to add unique properties to this kind of paint: antibacterial, resistance to mechanical influences, ability to reduce contamination.
The paint is applied by roller, brush or sprayer on the prepared cleaned strong surface of plaster, concrete, brick, plaster, fiberboard, wallpaper and has good hiding power. Depending on its properties, it can be applied once or twice. It may be necessary to prime walls and ceilings.
The standard paint dries completely in 3-4 days.
The term “interior paint” is most applicable to water-based compositions.
Silicate paints
Silicate paints are a mixture of pigments and fillers with an aqueous solution of liquid glass, creates a decorative water-repellent coating. But it is a two-component composition and requires preparation immediately before painting. In addition, the application process is quite time consuming. Although the paint is designed for exterior and interior work, it is rarely used in interiors.
Oil paints
Oils – dense or ready to use formulations made by mixing pigments and fillers in olive (binders). The same olive is brought to working viscosity. Color palette is diverse. Coating is not particularly decorative, but it performs a protective function. If you follow the technology of painting, it does not require renovation for 3-4 years.
Nowadays oil paints are practically displaced from the market by alkyd paints based on pentaphthalic, glyphthalic and styrene binders. But it is better not to use them in rooms with prolonged stay of people.
Interior paint for walls and ceilings – what is the difference?
The difference in the degree of impact on vertical and horizontal surfaces is obvious:
- warm air to the ceiling dust rises,
- while walls are more susceptible to contact contamination.
Considering these features, dust-repellent and many types of washable and wear-resistant paints for walls are now produced.
Regardless of the film formulator all high-quality interior paints are waterborne (water-dispersion). They are subject to higher requirements for the restriction of organic compounds and environmental purity of the components.
The palette of most manufacturers is diverse and allows picking up not only the desired color, but also its hue. There are versions of paints only in white, but by adding liquid dyes, you can always pick up the desired color.
Water-dispersed washable paints for interior use are more or less similar in composition and basic properties.
Innovative paint materials
For information, we would like to present the innovative developments of different manufacturers. Some of the types shown in the table in the picture can be categorized as “special”, so specific are their properties.
I would like to note that the types and qualities of paint listed here have a place in the range of many manufacturers: different degrees of gloss, resistance to abrasion and washing, fungicidal properties, even paint for allergic people – there is a lot to choose from.