Matting and Hinging Flat Paper Objects

The standard mat is made from two pieces of pH neutral paper board of the same size, hinged together along one edge. It consists of a backboard to which the paper object is hinged and a front, or window, board in which an opening is cut to display the paper object (Fig. 1).

Figure 1. Components of a standard mat.

The window board and backboard are hinged with gummed cloth tape and the object is hinged to the backboard with Japanese paper using cooked wheat starch paste. The T-hinge, also known as T-hanger, is the hinge most commonly used to attach paper objects into mats.

Each T-hinge consists of two rectangles of Japanese paper, one larger than the other. They are put together in such a way that the larger rectangle overlaps part of the smaller, creating a T-shape. This hinge is very strong and is routinely applied to those paper objects whose edges will be covered by the window board of a mat.

• 100% polyester fabric cut into squares
• Alkaline buffered paper board box
• Blotter squares
• Bone folder
• Dissecting needle
• Gummed cloth tape, 100% linen, pH neutral with acrylic adhesive
• Heavy duty hand-held knife, or hand held mat cutter or mat cutter that guides a blade along tracks (more expensive, but more accurate)
• Japanese paper
• Lead weights
• Nail file
• Paint brush (for applying paste)
• Paint brush (for feathering paper)
• pH neutral board, 4ply to 8ply
• Polymethylmethacrylate squares, 1/4in
• Ruling pen
• Silicone release paper
• Tweezers
• Wheat starch paste, cooked
  
  
  

Mat and Window

1. Measure the paper object to be matted. Decide on the total dimensions of the mat and the size and position of window.
2. Cut two pieces of board to the above determined size. The grain (machine direction) of the board should run parallel to the longer dimension of the mat.
3. On one piece, mark the 4 corners of the window in the desired position and cut the window with knife or mat cutter. The edges of the window opening can be cut at a simple right angle or beveled to 45º.
4. Remove the cutout to form the window.
5. Slightly blunt the edge of the sharp bevel that rests against the paper object with a bone folder to prevent possible damage, or sand with nail file.
6. Hinge together the backboard and the window board on the inside with 1in wide gummed cloth tape. Apply tape along one of the longer sides, parallel to the grain. A hinge in this location produces the sturdiest structure. If a mat is wider than it is high, it is hinged along the upper edge; if it is higher than it is wide, it is hinged along the left edge so it opens from right to left like the cover of a book (Fig. 1).

T-Hinge (Hanger)

1. Select a Japanese handmade paper of the weight and color desired (See Comments).
2. Prepare the smaller rectangle or tab that is to be attached to the paper object. This paper forms the stem of the T. Tear or “feather” with a needle the edges of this paper tab so that an irregular edge is formed and the long fibers are left extending out along the edges (Fig. 2). Do not cut the tab with scissors. Thin or brittle paper objects could be damaged by the relatively sharp edge of a cut tab.
   
   
   Figure 2. Feathering techniques.
   (a) Japanese paper is torn against a straightedge
   (b) The paper is scored lightly along a straightedge with a dissecting needle.
   (c) A thin line of water is drawn along the straightedge with a small ruling pen (see detail) or brush.
   
   
3. Prepare the larger rectangle of paper that forms the crosspiece of the T. Feathered edges are unnecessary because this part of the hinge does not touch the paper object.
4. Place the paper object face down on a smooth, flat, clean surface.
5. Lay the smaller hinge tabs (stems) part way over each other on a smooth blotter so that a portion of the long side of each tab, not to exceed one half, is exposed.
6. Cover the top tab with waste paper so that the same amount is exposed as on the other tabs. When determining the portion of the stem tab that is to be pasted, remember that each stem tab should overlap the edge of the paper object only enough to ensure that the attachment will be sufficiently strong to support the paper object securely as it hangs in the mat.
7. Apply the paste to the tabs, from the center to the edges, with a small brush using even strokes. When the paste is first brushed on, the surfaces of the hinges glisten. The disappearance of this glistening indicates that excess moisture has been absorbed by the underlying blotter and the hinges are ready to be placed on the paper object.
8. Place the pasted stem tabs onto the verso of the paper object at selected points along the top edge.
9. To ensure a strong bond, gently rub the damp hinge with a bone folder through a piece of silicone release paper.
10. Place a weight over the tabs cushioning them with a piece of silicone release paper and a piece of blotting paper and leave to dry. Weight the tabs while drying to avoid cockling.
11. When the hinge tabs are dry, place the paper object on the backboard with the image correctly positioned in the window opening. Hold it in place with one or two light weights, cushioned by blotters.
12. Apply paste to the entire surface of each of the second, larger tabs (cross pieces) of Japanese paper. With fingers or tweezers, place them over the free ends of the stem tabs in order to stick them down to the backboard, thereby forming the T shape from which this hanger construction derives its name.
    
    The crosspiece tabs should be placed perpendicular to the stem tab and centered. Place them at a distance from the top edge of the paper object that is equal to or slightly greater than the thickness of the paper object. The crosspiece tabs are correctly placed if the paper object is free to flex on its hinges so that the verso is accessible for examination, and the object is held in the mat securely enough that it will not shift if the frame is jarred (Fig. 3).
    
    
    Figure 3. Attachment of T-hinges. Stem tab is adhered to the back of the
    artwork and a crosspiece tab is used to attach the stem tab to the backboard.
    
    The stem tabs attached to the paper object are never pasted directly onto the backboard. They are therefore able to move slightly as the paper object expands and contracts in response to fluctuations in environmental conditions, and thus reduce the stress that is placed on the paper object (Fig. 4).
    
    
    Figure 4. Completed T-hinge.
    
    
13. Close the window board when the hinges are thoroughly dry.
14. Store the matted objects in an alkaline buffered box.
    
    
    

Standard mat sizes are often established for large collections to simplify storage and display. The dimensions of these mats are usually dependent upon the sizes of commercially available drawers and print storage boxes, although boxes also can be made to order.

The most aesthetically pleasing dimensions should be chosen for the window opening. The only rule is that one should not cover any part of the image or printing plate mark. Many paper objects have blank paper borders. A window mat that overlaps these borders will gently restrain the paper object, thus providing a more secure housing. However, as in the case of a paper object with an image that extends all the way to the edges of the paper, it is sometimes desirable to cut the window large enough for the entire paper object to “float” in it with all its edges exposed.

The window board should be thick enough to ensure that the paper object does not touch the glazing, if and when it is framed. 4ply board is thick enough to protect most paper objects, although particularly large or cockled paper objects may require 6ply or 8ply board.

Stamp hinges and glassine tapes, although frequently used to hinge paper objects into mats, are not suited for that purpose because they are composed of impermanent materials and are not strong enough for even the lightest papers. Gummed kraft or cloth tapes are also unsuitable as hinges because they are too strong and inflexible, and have sharp, potentially cutting edges that could injure brittle or delicate papers. In addition, they contain materials that could stain the paper object.

Currently available pressure-sensitive tapes, even those that claim to be “archival” are totally unacceptable for hinging, as are rubber cements, white synthetic glues, and spray adhesives. These materials leave unsightly residues and stains that in time become difficult or impossible to remove. Even shortly after application, they can only be removed safely with organic solvents by a procedure that requires specialized equipment and skills.

The material most favored by conservators as an adhesive for hinging is cooked wheat starch paste. If properly applied, it should be reversible and non-damaging.

Many of the difficulties that are encountered in the use of starch paste are due to poor control of the high moisture content in this adhesive. Care must be taken in applying as well as drying the paste. Too much moisture in the paste will cockle or stain the paper object. Excessive paste on the hinge tab will pull or pucker the surrounding paper as it dries. Dried excess paste can cause a stiffness in the area of the hinge that might result in the splitting or tearing of the surrounding, weaker paper.

There are many variables to consider in the process of hinging, and decisions regarding the number and type of hinges required for a specific paper object are governed by two basic rules: first, one should use as few hinges as possible, while still providing the requisite support for the paper object; second, the thickness and the stiffness of the hinge should never exceed that of the paper to which it is applied.

The exact size and number of hinges, their location on a particular paper object, and the weight of the paper from which they are made are governed by the size, weight, condition, and anticipated use of the paper object. Three or four hinges can be used. One can be located at the top of the paper object close to the left edge, and another close to the right edge (See figure 4 for proportions). The other hinge(s) will be located equidistant from the first two. 

Smith, Merrily A. [compiler] 1981. Matting and Hinging of Works of Art on Paper. Preservation Office, Library of Congress, Washington, DC.