MICRO-DOT ADHERING FOR PAPER CONSERVATION AND OFFSET APPLICATION OF PASTE

The author proposes a new technique for adhering papers for conservation procedures: micro-dot adhesion. Adhering is one of the key techniques in p"lper conservation. In some cases, waterbased adhesives such as natural starch paste and synthetic methyl cellulose cause trouble with water-sensitive materials. The micro-dot application of paste provides a minimal quantity of the paste. (The percentage amount of paste is roughly estimated from comparison with a graphic designer's screen: it might be 5% or less of the entire surface.) As a result, the paste stays on the surface and hardly penetrates inside. These facts allow water-based paste to be applied to water-sensitive materials for adhering. This is a very useful advantage for practical conservation work. Conventional starch paste, methyl cellulose and hydroxypropyl cellulose in water can be used. Another advantage is that it minimizes drying time, shrinkage and distortion and prevents the adhered papers becoming hard and solid. Furthermore, it offers easier detaching of the adhered papers. Water is not necessary for removing adhered paper, and inserting a thin spatula will be enough to detach the papers. It means that micro-dot adhesion is an easier, reversible method for paper conservation. Application of the paste can be done by various kinds of printing technique such as an offset technique with letterpress and a stencil technique. An ink-blotter has good shape and structure as an applicator for the paste. Instead of blotting paper, a net covers the bottom surface. The net surface of the blotter picks up paste from the table on which the paste has previously been applied flat. For offsetting, the blotter is then rolled on a paper that is to be used for mending. The paste is transferred to the paper from the net in dots and it is ready to use. For rather larger paper, a stencil is useful. A stencil paper having tiny holes, fixed on a frame at its edges, is used for application of the paste just as it is used for silkscreen printing. A larger amount of paste can be applied through the thickness of the stencil paper. The fluffed-up surface of Japanese paper is used for soft and flexible lining. Japanese paper is easily fluffed up by brushing the surface with a hard brush. The paste is applied on top of the fluffed-up fibres by an offset technique. First the paste is applied on a board, and the fluffed-up paper is then gently laid down on the pasted board. One soft brushing is enough to offset the paste to the top of the fibres. The technique is effective in the case of pasting a hinge-paper tip for matting a print. Sometimes an original print can show partial distortion caused by pasting hinge-paper at the corners. The micro-dots do not need much paste, so the pasted part does not contract as much as in the conventional method, because the paste is applied individually in tiny dots and there are many spaces between the dots. The usual, conventional way of pasting a sheet of paper, large or small, has been flat application by brush, even though the consistency of the paste is controlled. To repair a tear in the page of a Japanese book from the eighteenth/nineteenth century, thinly diluted paste is used to prevent the repaired part becoming hard. But thin paste can easily penetrate too much; blotting paper has to be inserted to dry it and to prevent bleeding to the next pages and shrinkage. Drying takes time. The dot-pasted mending paper is first put in a gutter-shaped paper carrier, and the carrier is inserted between the pages. Then the page is lightly pressed and the cmTier is withdrawn, leaving the mending paper. The mending paper does not adhere as strongly as in the conventional method. But such strong adhesion is not needed, because the book is handled carefully in a mu~eum collection and not treated as it was in private, everyday use. Advantages of the micro-dot technique: