MatBoard Types for Picture Frames
There are three components typically used to manufacture mat board, and we offer all three types:
General Overview - The short and quick version
The best picture framing mat you can buy is 8-Ply Rag matboard. It is museum quality for very long term conservation matting, is naturally inert and acid free. The Bainbridge Alpharag also has the Bainbridge Artcare treatment which proactively traps and neutralizes pollutants and acid by-products that can damage artwork. The 8-ply Rag matboard has the added advantage of being exceptionally thick with a resulting bevel of 1/4 inch which helps add considerable depth to the picture framing package.
Another good choice is Bainbridge Artcare Alphamat cellulose matboard. It also is museum quality for conservation matting, is naturally inert and acid free and has the Bainbridge Artcare treatment.
Papermat is inexpensive and generally considered a temporary solution for framing items that do not require any conservation measures or archival framing. Papermat is not recommended if you want the artwork to last more than five years without showing signs of deterioration.
A Little More Overview Information
Mat board composed of cotton is typically referred to as "rag" board and is generally composed of separate plies of cotton board dyed for color and layered together in 4, 6, or 8 ply. The thickness of 4-ply is generally about 1/16 of an inch thick and 8-ply is about 1/8 of an inch thick.
Alpha cellulose and paper mat boards are not separate plies but will often be referred to as 4-ply to give a relative indication of their approximate thickness.
Another term thrown around a lot is museum quality mat board. The highest quality cotton rag boards will often have much smaller color selection since they are manufactured with dyes that are less likely to introduce harmful components into the frame package. All Bainbridge rag board is like this, as is the Crescent RagMat® Museum rag is manufactured like this.
Cotton and alpha cellulose are more naturally inert (acid free) and may or may not be buffered. Buffering allows the mat board to absorb harmful acidic components from within the frame environment (such as a wood frame which is very acidic). In general you would want the mat board to be buffered since it will help absorb acidic compounds being emitted from a wood frame and from the wall.
In addition to looking for acid free, you also want to look for lignin free which is nearly as critical for archival purposes. Cotton and alpha cellulose are usually lignin free, while paper mats typically are not.
Wood pulp (or paper mat) is naturally acidic but can be buffered with calcium carbonate to temporarily shift the ph balance to alkaline. Some companies will market this as acid free but it will return to being acidic and start to harm the image in about five years. Paper mats are by far the least expensive and are considered by the manufactures to only be suitable for “temporary framing”.
Although the vast majority of framing mat and mount boards are buffered, a small selection of types and colors are available “unbuffered”. This is for a handful of much less common acid photographic printing processes such as Cyano and dye transfer which can react to the buffering.
In short, you can look for buffered, acid free, lignin free, Artcare process, thickness and core color.
The color of the mat core will be visible in the bevel cut of the mat surrounding the image.
Cotton rag mat board, including Crescent RagMat® Museum and Bainbridge Alpharag, dyes all the plies the same color so the rag mat board will have a consistent color all the way through.
Most other (non-rag) mat board consists of a core made of cotton, alpha cellulose or paper that is typically cream colored or white and then laminated with the mat color. Most manufacturers will offer a few other choices of core board color, such as black.
Other marketing information
Some types of prints are believed to be more susceptible to fading from environmental pollutants than they are from UV light. Another excellent protection is a coating of zeolite molecular traps which allow the mat board to absorb harmful environmental pollutants. Bainbridge is the only company manufacturing mat board with this technology and they market it as treated with “Artcare”. Due to patent restrictions no other company can use this technology. In a few years this patent will expire and you may see the technology picked up by other companies. The Artcare process also helps increase the time it takes for the mat board to become contaminated.
Bainbridge and Crescent are two of the largest and most common mat board manufacturers. Most custom frame shops around the country will offer a selection of mat boards from both of these companies. Most companies have many different levels of products from the 100% cotton rag board that is purified, colored with archival dye, buffered and treated with zeolites, all the way down to laminated paper mat board for decorative use. At the lowest level of paper mat board there will be inconsistencies in the color of the core (cream vs. white) and the thickness. The least expensive mat boards are just a little thinner (less material) with no option for white core or black core.
Bainbridge Alpharag is true museum quality with the highest quality and highest grade of archival image preservation that money can buy. It is acid free and has the Bainbridge Artcare treatment.
Bainbridge Alpharag Features:
- 100% cotton rag
- Solid color throughout – from surface to bevel
- Includes Artcare™ Archival – Plus protection*
- Acid and Lignin Free
- Fade and bleed resistant
- Buffered to maintain alkaline pH
- Passes the Photographic Activity Test
- Meets and exceeds ANSI/NISO A39.48-1992 Regulations for paper permanence
* The Bainbridge Artcare™ process proactively traps and neutralizes pollutants and acid by-products that can damage artwork.