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Tapa has been
found extensively in nearly all cultures along the Equatorial belt and is
made by what is possibly the oldest papermaking technique – one
still practised in some parts of the Himalayas and South East Asia. Indeed,
recent archaeological excavations in China have revealed some of the oldest ‘tapa’ paper
ever found which shows that paper was being produced in China before western
records began.
The tapa technique involves cooked bast, which is flattened with a wooden
hammer to form a thin, fibrous layer and then dissolved in a vat with water
to make a pulp. A screen consisting of a wooden frame with a fabric base
is then laid in a puddle or big basin and floats with the fabric just under
the surface of the water. The papermaker then pours the quantity of pulp
needed to make one sheet into this ‘floating mould’ and spreads
it evenly, by hand, across the surface. The screen is then carefully lifted
out of the water, allowed to drain off and a sheet of paper forms on the
wire. Once the water has dripped off, the screen is placed in the sun or
near a fire to dry. When dry, the sheet easily peels off and, apart from
possible smoothing, requires no further treatment. This technique has two
basic drawbacks. Firstly, a separate screen is needed for each new sheet,
and is only available for use again after the last sheet has dried. And secondly,
an increase in production can soon lead to a shortage of raw material, since
fresh bast is not always available everywhere in the required quantity.
The fibres normally used for textiles, like flax and hemp,
also served as substitutes for bast. In later times, the fabric was replaced
by fine
bamboo
sticks, which freed the papermaker of the need to let the paper dry naturally
in the mould, since the poured or ladled sheet could be ‘couched’ off.
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