Hand Papermaking
In many areas of developing countries paper is scarce. Rural
schools may not have
enough paper for their students and market goods may be
wrapped in old newspapers
if at all. Often this is because resources are not available
to invest in
modern papermaking factories, which require large amounts of
energy and raw
materials if they are to be economical.
But paper can be made in small shops in small quantities.
Access to electricity
makes some of the steps easier, but is not absolutely
necessary. (Indeed, paper
was made this way for many years before electricity was
discovered.) In a situation
where paper is scarce and expensive, it may be worthwhile to
consider
small-scale papermaking as a source of school supplies or as
a small business.
Such a business might produce heavy coarse paper for
packaging or even thick
paper egg cartons, plant pots, and so on.
PAPERMAKING PROCESSES
Whether paper is made in a home or school workshop or a
small factory, the
production processes for making paper by hand are quite
similar. The scale of the
equipment changes with the volume of production and the raw
materials vary with
what is available and the quality of paper to be produced.
Pre-processing
Cotton or other rags and waste paper to be recycled are
sorted thoroughly to
remove all non-fibrous materials such as staples, paper
clips, cellophane, nails,
buttons, zippers, etc. Both rags and paper are cut or
shredded into small pieces.
Pulping
The cleaned and shredded raw materials are brought to the
boiling point and
cooked for two to six hours. They are rinsed thoroughly to
remove impurities that
might have separated out during the cooking process.
The beater--this can range from a kitchen blender to a
specially made tank--is
filled with the required quantity of water, and the cooked,
chopped rags or paper
are added gradually with high speed agitation. Bleaching
powder or liquid bleach
(1 percent) is then added. The pulp is washed thoroughly, a
process that may take
another six to eight hours. Additives used may include
titanium dioxide or other
fillers, dyes (for colored paper), or optical bleaching
agents (for white paper).
Rosin soap and alum are added later.
Lifting, Couching, and Stacking
When the pulp process is complete, the pulp is transferred
to storage containiers
or vats. Depending on the scale of the operation, the pulp
is then mixed with a
sufficient quantity of water to dilute it to form a uniform
suspension, free of
lumps. In the home workshop, the pulp is mixed in quantities
to make one sheet
at a time. In the small factory, a larger quantity may be
mixed at one time. The
diluted pulp is then lifted from the water on wire screens,
and the resulting
sheets are covered by felt or other absorbent cloth. With
the cloth is place, the
still wet pulp layer is carefully lifted from the screen.
This process is called
couching (pronounced cooching). The couching cloth, paper
side down, is placed
on a felt covered board and smoothed to remove wrinkles or
air bubbles. Each
succeeding sheet is placed in a stack over the first.
Pressing and Drying
When a sufficient number of sheets have been formed, they
are put under a press
to remove the water. The sheets are then separated and, to
avoid shrinkage,
placed under absorbent boards and pressed again. The sheets
are hung to dry in
bunches of three to six, according to thickness, or dried in
a warm oven.
Sizing
Sizing gives paper a harder finish so that water based
paints and inks will not
bleed or run. Paper may be sized internally, by adding the
sizing agents to the
pulp, or externally, by painting or dipping the dried
sheets. For internal sizing,
alum, rosin, gelatin, cornstarch, or linseed oil may be
added in very small
quantities at the end of the pulping stage. For external
sizing, the dried sheets
are dipped in a dilute glue or starch solution, pressed to
remove the excess, and
hung up to dry again. In the home workshop, the individual
sheets may be painted
with the dilute solution.
Blotting paper, filter paper, toilet tissue, grey board, and
some art papers may be
require very little, if any, sizing.
Calendering
The dried sheets are placed alternately between metal plates
into a stack or
"post." The stack is passed between calender
rollers to obtain the desired
smoothness. This can be done in the home workshop by
pressing the paper sheets
between sheets of aluminum foil with a hot iron.
Sorting and Cutting
After calendering, the sheets are carefully sorted and cut
to size for packing,
storage, and/or shipment.
MAKING PAPER IN THE SMALL WORKSHOP
Papermaking at this scale can be done as hobby, for gifts,
or to supply schools.
The necessary equipment may already be available in some
kitchens, but the
markets should be considered carefully before any investment
is made.
This process assumes that waste paper or cotton cloth will
be used to make the
paper. Approximately 50 sheets of 21.5cm x 28cm (8 1/2"
x 11") paper can be
made from a half kilo (about a pound) of waste paper.
Household bleach, alum,
gelatin, cornstarch, and animal glue may also be needed. And
ordinary fabric dyes
can be used to produce tinted or colored papers. As
described here, the availability
of adequate water and electrical or other power supplies is
also assumed.
Equipment and Materials
The following equipment is needed:
Deckle box and
mold, made of oiled wood (figure 1)
fg1x394.gif (600x600)
Power food mixer
or blender
Stainless steel or
enamel pot (not almuinum)
Steam iron
Stove with oven
Sink, tub or wash
basin
Couching cloth
(e.g., cotton sheeting), cut to size
Felt or absorbent
terry cloth, cut to size
Thin metal sheet
Flat
"receiving" board, 1cm (1/4") plywood or other board
Pulping
Choose paper with minimal printing. Old envelopes are good
for this reason; the
glue on the flap won't matter. Colored paper is acceptable;
the dye usually comes
out when it is boiled. Avoid paper that has "wet
strength" such as paper towels.
Be careful how many brown paper bags you use. Unbleached kraft
paper lowers
the brightness or whiteness of the pulp, but it is strong
and will give your paper
toughness.
Newsprint alone makes a weak pulp, grey in color. It adds
little but bulk. Cotton
or other cloth or yarns may also be used. They must be cut or
shredded into very
small pieces to avoid jamming the mixer.
Cut or tear the paper into small
pieces, about 5cm x 5cm (2" x 2").
Shred any cloth that may be used.
Put the pieces in the pot, cover
with water, and add a few tablespoonfuls
of household bleach. Turn
on the heat, cover the pot, and
bring to a gentle boil. Stir
occasionally for a couple of hours
to ensure that the bleach is mixed
and all the paper is wetted down
well, then cool.
After the batch has cooled, try to
break up the lumps and any
remaining pieces of paper still
holding together. The smaller the
pieces in the beginning, the easier
this step is now. (The pulp can
then be drained and stored in
plastic bags in a refrigerator, if
you have one, until you are ready
to make the sheets. It will keep for
weeks without any change.)
Making the Sheets
Take a lump of the semi-moist pulp you have prepared. Press
as much moisture
out of it as possible to leave a ball about the size of a
pigeon egg (7g--1/4 oz--dry
weight). This is enough pulp to make one 21.5cm x 28cm
sheet. Make the
sheets, one at a time, as follows:
1. Blend and mix
pulp in blender 3/4 full of water. Add additives.
2. Put mold in box,
screen side up and immerse in sink.
Rap box to get
rid of air bubbles.
3. Pour pulp into
box.
4. Holding box
down, agitate the water in the box with fingers so that the
pulp spreads
evenly over the mesh.
5. Grasp box and
mold firmly and lift quickly and evenly to surface (feel
suction).
6. Hold for 10
seconds or so to drain.
7. Lift up out of
water and hold vertically to drain. If sheet looks okay,
proceed; if
flawed, put box and mold back into sink. Repeat steps 4 to 7.
8. Set box on flat
surface and carefully remove box. Note: Water drops on
wet web will make marks!
9. Carefully lay cotton couching cloth over web and smooth
gently.
10. Place absorbent felt over couching cloth. Smooth and
press down from
center out.
11. Remove felt and wring out water.
12. Repeat 10 and 11 until no more water comes out.
13. Couch off sheet, starting at corner and peeling back
quickly.
14. Place couched sheet, paper side up or down on flat
absorbent surface.
Smooth and press
down to remove trapped air.
15. Repeat for each sheet until a neat stack is built up.
Pressing and Drying
The sheets can be dried quickly by pressing them with a hot
iron and an aluminum
sheet or slowly (2-3 hours) by placing them in a
120[degrees]C (280[degrees]F) oven, with
the couching sheets tacked down to the receiving board all
along the edges of the
paper sheets. The first method gives a smooth surface on one
side, embossing
with cloth marks on the other; the second gives embossing on
both sides.
A very slick surface can be obtained by smoothing the couching
cloth, paper side
down, against an aluminum or oiled galvanized sheet. A
squeegee can be used to
get rid of all the air. Dry in air or in a 120[degrees]C
(280[degrees]F) degree oven.
Sizing and Coating
A simple method of internal sizing uses a combination of
pure gelatin and cornstarch
(either laundry or cooking type). The gelatin is dissolved
in boiling water
and cornstarch is added to make a clear, thick mixture to
add to the pulp. Use
about one teaspoon of this per 21.5cm x 28cm sheet.
Another simple internal sizing procedure is to add about 1/4
teaspoon of linseed
and/or a teaspoon of cornstarch solution while the pulp is
being mixed at step 1.
The oil is dispersed in the water and precipitates on the
fiber. The starch will be
caught on the fibers and during the drying stage will set to
give a stiffer sheet.
External sizing is done when the sheet is coated with a
water based solution
after the paper has been dried. With an ordinary 4cm (1
1/2") paint brush, coat
each sheet with a 7 percent straight corn starch solution.
one tablespoonful of
cornstarch added to a cup of water will be enough for 20 to
25 sheets (both
sides). Animal glue can be added to the starch to improve
the water resistance.
Modern glues can be added also.
When the coated sheets are nearly dry to the touch, place
them in a neat stack.
They should be somewhat limp but not wet. Put a metal sheet
or smooth board on
top. Allow the stack to dry overnight. The sheets can then
be trimmed if
necessary and packaged for sale.
MAKING PAPER IN THE MICRO FACTORY
On a somewhat larger scale, but still in an essentially hand
process, paper can be
made in a micro factory capable of producing about 240kg
(1/4 ton) of paper per
day. Such small factories are fairly common in India, and
VITA has assisted at
least one such operation in Tanzania. This process uses
wastepaper or rags to
make pulp, or pulp purchased from a pulp mill. It can
produce good quality bond
or drawing paper, card stock, school tablets, filter paper,
toilet tissue, grey
board, and album or blotting paper. It can also turn out
such articles as egg
cartons, flower pots, seed flats, hospital trays, and so on.
In addition to an identified, reliable market, the small
factory requires a steady,
reliable supply of raw materials, water, and power.
Suggested facilities include a
building of about 300 square meters for operations and a
shed of about 185 square
meters for collecting and sorting the materials. Six
administrative staff and as
many as 100 laborers working in two or three shifts are
needed.
The U.N. Industrial Development Organization (UNIDO)
estimates an investment of
approximately US$26,000 (1984) for the total cost of
installation. Production may
be increased by installing one or two more beaters and
operating the vats in
three shifts. (Beyond this capacity, however, economies of
scale decline, and
production moves up to small-scale mechanized plants.)
Sources:
Vogler, Jon, and Sarjeant, Peter. Understanding Small-Scale
Papermaking. Arlington,
Virginia: Volunteers in Technical Assistance, 1986.
Appropriate Industrial Technology for Paper Products and
Small Pulp Mills. Vienna
Austria: United Nations Industrial Development Organization
(UNIDO), 1979
Sheriff Dewji and Sons, Arusha, Tanzania
American Paper Institute, 260 Madison Avenue, New York, New
York