Topics in Photographic Preservation 1997, Volume 7, Article 12 (pp. 91-91)

Remoistenable Tissue, Part II: Variations on a Theme

Sarah S. Wagner

Additional uses of Remoistenable Tissue

As mentioned in the previous article by Irene Bruckle, the remoistenable tissue formula as developed at SUNY Buffalo can be modified for various uses. This short article will briefly outline some of these variations on a “theme.”

Tissue Preparation and Variations for Lining and Reinforcement

The original formula may be modified and experimented with to adjust the strength of the adhesive film layer, while the use of different screens adjusts the thickness and uniformity of film formation as mentioned in the previous article. Of course the choice of an appropriate tissue type and weight plays a crucial role, as it does with standard mending and lining. All three variables can easily be adjusted using this method. For example, one can adjust the ratio of wheat starch paste and methyl cellulose to form a stronger film layer (e.g., 1:1 mixture of wheat starch paste and Methyl Cellulose instead of the standard 1:2 mixture). This strength of adhesive may be more desirable for lining very thick papers or photographs or even items mounted on boards.

The 1:1 mixture in itself can be diluted to various consistencies with water, gradually weakening what is otherwise a very strong adhesive. While an undiluted mixture coated through standard window screening results in a heavier film formation, the use of Pecap or silkcreen can allow one to create “gossamer” thin adhesive films, especially with a diluted mixture. Such gossamer thin coatings on lightweight tissue (e.g., Tengujo or Barcham and Green Lens Tissue) are appropriate for lining lighter weight paper and photographic objects.

Thick adhesive layers (as described above) can be applied to lightweight tissue such that some of the adhesive migrates through to the back creating a somewhat double-sided coating. A double-sided coating is useful for lining a photograph onto a mountboard. In addition, it can be used to repair broken mountboards–the broken mount can be delaminated and the two layers reattached to each other using the double-sided tissue (or two pieces of tissue placed back-to-back), thereby repairing the break and strengthening the board.

Use of the Tissue for Mending

As discussed by Bruckle, the original formula and technique was developed initially as a lining method for moisture sensitive paper objects. However, the tissue (or one of the modified tissues described above) can be used for the mending of paper and photographic documents, whether or not they are moisture sensitive. Batches of various weight tissues (with various strength adhesive layers) can be prepared in advance, and torn into mending strips to have available for ready use. Not only does this save time, but the remoistenable tissue dries quickly as a mending strip since it needs to be only lightly misted to activate. Likewise, ultrathin tissues (with light adhesive layers) may be used to bridge weakened areas, such as those damaged by iron gall ink, while remaining both relatively transparent and keeping the use of moisture to a minimum.

Use of the Adhesive Film

One by-product of preparing the tissue is that the excess of adhesive mixture is forced to the margins of the polyester film used for the coating where it then dries and forms a thin adhesive film unsupported by tissue. This excess adhesive film then can be delaminated from the polyester sheet and used as adhesive when reactivated by the introduction of moisture via a brush, ultrasonic mist, or fine spray. The unsupported adhesive film is most useful for situations where water induced staining is problematic, such as with deteriorated poor quality papers and mounts, or when normal paste solutions do not seem to adhere well. For example, the film can be used to set down lifting red-rotted leather onto book boards, to consolidate brittle poor quality mountboards whose corners are frequently worn and delaminating, to readhere the lifting corners of photographs back onto their mounts and supports, and even to mend old tears and breaks that do not wet out well.