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Last updated March 2004.

Manual Guide No. 38A (1986)

Mylar Sleeve.

The Mylar/polyester sleeve is designed to cover a book which has basically sound structure i.e. boards and spine still firmly attached), but which has covering material of a flaky or generally powdery nature. The sleeve provides some slight reinforcement to the structure , but its primary purpose is to cover the deteriorating surface while leaving the spine information visible. The design takes into account the possibility that the sleeve may have to be removed, so all attachments are mylar to mylar.

Materials and Equipment.

Mylar polyester or Mellinex is the best material to use because it is archivally sound. While archivally sound material may seem unnecessary for the task at hand, it is best to stock chemically stable materials so that they may be used for other, more demanding tasks. A roll of 3M, No. 415, double-sided tape of l/4" or 1/2" in width is the only other material required.

Scissors, a 24" steel ruler, a "China Marker" (pencil designed to write on glass or plastic), and, if possible, a board shear, complete the equipment.

Measurement Formula.

The sleeve consists of a single sheet of Mylar wrapped around the book and turned in at the head, tail and foredge. On the longest dimension, the Mylar is four times the width of the book plus the width of the back. On the short dimension, the Mylar is the height of the book plus 6 centimeters. For example:

if a book measured 24.0 x 16.0 x 4 centimeters,

16.0 width of book
x4

64.0
+4.0 width of back

68.0 long dimension of Mylar

24.0 height of book
+6.0 (for turn'ins)

30.0 short dimension of Mylar

the total size of the Mylar sleeve would be 68.0 x 30.0 centimers.

Construction.

A line is marked with the China Marker along the longest dimension of the Mylar, 3.0 centimeters from the edge, and repeated at the opposite edge.

The book is placed between the lines with the back at the center, and slit lines are marked. The book is rolled over across the center, and similarly marked on the other side of the Mylar.

The Mylar is now cut with the scissors, leaving the slits at the center to provide reinforcement for the back of the book. Strips of double-sided tape are attached to the "flaps" as indicated.

Placing the Sleeve on the Book.

The books is laid onto the Mylar, and the flaps pulled over onto the lower board. While maintaining the book's position, the protective film is removed from the tape, and the fore-edge flap set firmly into position. Before repeating the
procedure on the other board, the small flaps at the head and tail should be folded in to provide reinforcement.

It is important to note that the Mylar Sleeve is not a repair or strengthening device, and that detached boards or broken joints must be dealt with by the use of other methods.