This guide will tell you all you need to know about picture framing and matboards. We start with quality, which is determined primarily by a mats thickness, acidity, core, color (surface/core) and finish. This primer will go into detail about how these different characteristics affect the quality of the matboard.
The most important aspects of the finish are the bevel, cut accuracy and cleanliness of the mat.
Matboard is typically measured in PLY, which is not standardized like inches, making it misleading. Mats come in either 4 PLY (0.040-0.052″) or 8 PLY (0.125″) but that doesn’t mean all PLY are the same. For example, there are 0.040″ 4 PLY and 0.052″ 4 PLY. Double or triple 4 PLY mats can also be used in place of 8 PLY mats to get a similar effect. The thicker the photo mat is, typically the higher the quality and price are. The advantages of a thicker matboard are:
Our Economy (Berkshire) mats are 0.040″ thick as compared to 0.052″ for the Decorative and Conservation mats, which is part of why Berkshire is the cheapest mat. Conservation matting also comes in 8 PLY and they are our highest quality matboard.
The acidity of a matboard determines how long it will last and be impacted by sunglight and other atmospheric conditions. We split up acidity into two categories, acid free and not acid free. True, 100% acid free is only available in cotton-fibre based matboards, these are used for museum art that needs to preserved for hundreds of years. Paper mat that is made of wood-pulp is often called acid free as the acid is buffered out through a chemical process. These are the Conservation brand of matboards that are sold by most high-end frame shops. The more common paper mat, often called Decorative is not acid free but wll still last many years depending on exposure to sunlight and the quality of the glazing. You’ll find these in retail locations. It’s also important to note that acidity is a factor in both the core of the matboard and the surface. The core is what the matboard is composed of (paper is then adhered to the core to give the matboard color and texture), White and black cores have acid free cores, but not necessarily acid free surfaces which means that the core will retain its color, but the acidic surface will still fade and potentially damage the art work over time. Cream/standard cores are not acid free in either the surface or the core.
Acidity has two main problems:
Conservation Select mats are what is commonly called acid free, Berkshire and Decorative mats do not have acid free surfaces.
The core is the material that the matboard is made of. It is revealed with the bevel cut, the inside edge of the mat after a 45 degree cut is made. It functions as a secondary border and is typically 1/8″ of an inch. Retailers mostly use cream/standard core as it is the cheapest, but white and black core provide a much more professional finish. Core comes in three colors:
Conservation Select mats are what is commonly called acid free, Berkshire and Decorative mats do not have acid free surfaces.
Standard Core Matboard
White Core Matboard
Black Core Matboard
Matboard color is very difficult to judge, but the higher the quality the sharper and more intense the color is. Matboard can come in many forms: