Acrylic paints consist of pigments suspended in an plastic polymer emulsion. Introduced in the late1950's, they showed extraordinary promise because of their brilliant color clarity, ultraviolet light impregnability, flexibility, and liquid repellant abilities. They are considered a viable alternative to oil paints because of these attributes, as well as their quick drying time. (Acrylics can dry to the touch within an hour or less, depending on the brand and thickness of application. Oils, by comparison, can take as long as several months to thoroughly cure). And although the permanency of acrylics is being debated by conservators, they appear more stable—whereas oil paints normally turn yellow and crack as they age, acrylic paints, at least in the fifty years since their introduction, do not.

In order to achieve and maintain these performance properties, a combination of additives, which vary between manufactures, are blended into the paint. Wetting and dispersing agents are added that allow the pigment agglomerates to break apart - a critical process in developing color strength, coalescing solvents are added to ensure film formation under varying atmospheric conditions, defoamers are necessary to reduce the inherent tendency of the emulsions to foam, preservatives are supplied to avoid dilution as water and other components are added, thickeners and rheology modifiers are required to achieve the desired viscosity and flow properties, and freeze/thaw stabilizers are added to prevent freezing, thus, the formation of ice crystals in the waterborne paint.

Early on, artists and art conservators generally assumed acrylic paints to be simply indestructible and information regarding acrylic conservation techniques around this time was minimal. In the mid-1970's, conservators began scrutinizing the properties of the additives, but met with little success in determining their innate characteristiscs or their possible negative effects upon the painting. Even today, definitive restoration treatments remain speculative and inconclusive.

Because of this ambiguity, most conservators agree that preventive maintenance is crucial to any acrylic artwork’s longevity. Some suggest a hands-off approach— frame the painting, put it behind a glass glaze to reduce dust and to eliminate dirt and damage from handling (acrylic film becomes malleable at room temperature and can be dented with just fingernail pressure), and accept a small degree of deterioration without taking further action.

Acrylic paint is soft and the resins are non-conductive; that is, they hold an electrostatic charge that attracts air-borne particles. Because of these properties, they should be displayed in a dust-free, low traffic, air-filtered environment (the area should be vacuumed or mopped rather than swept to avoid stirring up dust). In addition, exposure to elevated temperatures should be avoided, especially in combination with dusty conditions, such as near hot air inlets or furnace vents, in direct sunlight, or stored in attics.

This is not to say that acrylic artworks cannot be self-cleaned from light accumulations of dust. Indeed, those with fairly flat surfaces can be gently wiped with a soft, clean cloth; for those with heavier textures, a soft paintbrush will usually do the trick. Instances of dirt and grime can be blotted off with a lightly dampened cloth. However, a small inconspicuous spot should be done first to ensure that the paint is not loosened or removed along with the dirt. Never use water to clean an acrylic painting—it could affect the liquid-soluble additives and could cause the thickeners to swell.

Mold growth, a problem with most types of media, has become an increasing concern among artists who paint in acrylics and with collectors, and removing it may not guarantee that the artwork will be restored to its previous pristine condition. Undoubtedly, the best cure for mold is avoiding high humidity levels and damp conditions in the first place.

As for protecting an acrylic painting with a varnish finish, once again there is no universal accepted agreement to do so. Given the characteristics of acrylic paints as described, the best protective finish for an acrylic painting could be one of the modern varnishes currently available as they can be easily removed with very mild solvents like turpentine, which should have a minimal affect on the paint itself.

If unsure about how to safely treat art made in acrylics, consult a professional conservator as appropriate for the piece’s needs.

Although conservation procedures regarding acrylic artworks have been debated for over three decades, scientific research dealing with the structure and components of these polymers, including the individual properties of the additives, and their molecular interaction with other materials such as priming and varnish are ongoing. Because remedial treatment with acrylic paintings remains exploratory, a few basic care procedures with this durable medium are essential.