A passepartout (also called a passepartout) is a border that surrounds pictures. It is usually made of matboard, a type of board manufactured specifically for this purpose. The matboard is cut to size, then one or more holes (openings) are cut to display extra space. Passepartouts provide important practical functions and also have a visual purpose.
What are the styles of passepartouts?
Passepartouts are an important part of the visual presentation in picture framing. Passepartouts can be used to emphasize a color in artwork or room decor, to emphasize a shape in art, or to increase size to create a dramatic image (especially for small pieces). Passepartouts can consist of a single piece of cardboard with a rectangular opening cut in it, but there are also double passepartouts, triple passepartouts, oval passepartouts, and a multitude of other decorative shapes and styles.
Why is a passepartout used?
The mat and backing board provide a support area for the artwork. The mat protects the hinges or other attachments that hold the artwork in place (and hides it from view, making it look better). Artwork can be attached to the underside of the window mat if the artwork is small, or to the backing board for larger pieces. Attaching to the backing board is preferred by professional framers.
How is the mat applied?
A mat can also help protect the artwork. It allows artists and collectors to place the artwork in the frame without touching the frame. A mat also allows air to circulate between the artwork and the glass substrate (the glass or plastic sheet that covers the art in a frame). This air gap is important: prints, photographs, and needlework should not be placed directly on the glass, as moisture can condense inside a framed piece and cause mold, mildew, and warping. Artwork pressed against the glass can stick to it. Since paper expands and contracts with changes in humidity, space should be left in a frame to allow the artwork on the paper to move slightly from side to side and top to bottom. Artwork that is properly hung on a mat has room for these movements.
What are mat materials?
There are two main types of mat materials in mats: acidic and “acid-free.” Older mats (wood-based paper) are typically acidic, as acid-free paper was not widely available or marketed until recently. While most new mats are acid-free, there are some that are acidic, and if the desired life of the piece being framed is more than 75-100 years, the framer should be asked about the acid content of the mats.
The difference is important for the long-term preservation of the piece, as acidic mats can cause brown stains, called mat burn, that bleed into the piece when viewed from the outside. While mat burn can sometimes be reversed by cleaning the piece, cleaning may not be possible if the piece is made with water-soluble inks or paints such as watercolors. Therefore, it is important to know if the mats being used are acid-free if the piece is going to be stored for a long time.
There are several categories of mat boards, all of which are separated by the level of protection offered to the piece or artwork being framed. While some say that acidic framing materials should be avoided for all but the most temporary frames, it is not possible to say that all “acid-free” mats are recommended for long-term preservation use.
Care should be taken when choosing the type of frame you want. Artwork that is intended to last for a long time (75+ years) can be damaged by improper mat boards that are deliberately used to keep costs down. However, quality non-archival mat boards may be suitable for photographic printing, laser printing, etc. that are not intended to last long. Additionally, prints made with the traditional chemical process of photographic film (i.e. darkroom development), unlike computer printing, are already slightly acidic in nature and are therefore much less likely to be damaged by non-archival mats.
Furthermore, proper “protective” framing includes all components, not just the mat board used immediately behind the glass. It is also important to ensure that the framer uses good preservation framing techniques if long-term preservation is involved.
Mats can be cut using mat cutters. These come in a variety of sizes and allow the mats to be cut with precision and accuracy. This makes it ideal for complex mats, multi-window mats, oval or shaped mats and even bulk mat cutting. Mats can also be cut by hand, but this greatly increases the chance of error. Unless otherwise specified, the opening is usually cut 3mm over the opening size, allowing the artwork to fit into the substrate. It is common practice to apply a backing panel to the back of the artwork to secure it before framing.
