Conservation Science

Paper 35

there are few free fibres and the opportunities for hydrogen bonding between
the impure cellulose fibres is limited. These “groundwood” or “mechanical
wood pulp” papers are cheap to make and are used in paperback books and
newspapers. Changes in production methods for the cheapest papers mean
that many of those papers are now more permanent.
It is now possible to consider two types of cellulose-based writing surface
that do not come into our definition of paper but which are important to the
paper conservator. Although paper was first made in China in about 105 AD,
the Ancient Egyptians made a writing surface of what we call “papyrus” from
about 3000 BC. The papyrus plant (Cyperus papyrus) has tall stems, approx-
imately triangular in cross-section, inside which there is a high concentration
of cellulose fibres as part of a cream-coloured, spongy material. Once the tough,
green outside layer is removed, thin strips of papyrus, a few centimetres wide,
are cut and laid side by side to form the shape of a small sheet. More strips
are then laid at right angles on top of these and the sheet is then pressed and
dried. Although this material contains fibres of cellulose, they are not sepa-
rated from one another, so it is not strictly paper. Another material, which is
similar to, but not paper, is barkcloth also known as kapaor tapain the Pacific
islands where much of this material is made. Barkcloth is made from the cel-
lulose fibres that are found beneath the bark of certain trees and shrubs (inner
bark). The fibres are first retted and then, beaten with grooved mallets to fur-
ther soften them and form sheets of matted fibres. While still wet, the sheets
are folded up on themselves and beaten further to spread and reform the sheets.
Barkcloth can be made into surfaces for writing on, made into clothing or
used in a multitude of ways.

1.2 Paper Size

The type of filter paper found in the chemical laboratory is made from cellu-
lose fibres only, but is of little use as a writing or printing paper as it is too

C

CH

CH 2 OH

HOH

H 3 CO

OH

C

HC

CH 2 OH

O

OCH

OH

3

Figure 2The basic structure of lignin