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PAPER
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PAPER
is a thin, flat material produced bythe compression of fibres.
The fibres used are usually natural and
composed of cellulose which are
subsequently held together by
hydrogen bonding.
The most common source of these kinds
of fibres is wood pulp from pulpwoodtrees, (largely softwoods) such as
spruce.
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However, other vegetable fibrematerials including cotton],hemp, linen, and rice may beused.
The cellulose from these plantsis used in making paper.
The more cellulose used to make
paper the higher the paperquality.
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Process of making paper
Paper manufactured is probably madeof
about one-third of the raw material
used to make paper is - woodchips and scraps left behind fromforest and sawmill operations.
These leftovers would probably beburned or discarded if not used by the
paper industry. Only about one-third of the fiber used
to make paper which the industry calls
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The amount of fiber in a cubic foot
of wood varies greatly from species
to species.
(broad-leafed species)
tend to have greater woodthan (conifers), meaning
they have more fiber per cubic foot
of wood.
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When trees are harvested forpapermaking, the limbs are removedand the trunk is transported to a pulpmill.
At the mill, the bark is removed andburned for fuel or processed to use asgarden mulch.
The wood is often chipped into smallpieces about the size of a quarter, andthen broken down further intoindividual
fibers in a process call . The pulping method influences the
amount of fiber the wood yields.
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Sometimes pulping is done mechanically bypressing and grinding the wood to separate thefibers.
This process is veryefficient. Up to 95% of the dry weight of the
wood is converted into pulp. Most newsprint is made from mechanical pulp,
recycled fiber, or a combination of the two.
Paper made from mechanical pulp is opaque
and has good printing properties, but it is weakand discolors easily when exposed to light dueto the residual in the pulp. (Lignin is anatural wood chemical that holds fiberstogether.)
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which a chemical/water solution dissolves the lignin to helpseparate the fibers.
The absence of lignin means that paper
made from chemical pulp is stronger andless prone to discoloration.
The pulp yield from chemical pulping ismuch lower, though, since the lignin has
been removed. Chemical pulps are used to makeshipping containers, paper bags, printingand writing papers, and other productsrequiring strength.
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Types of Paper
The type of paper being produceddetermines what pulping method is used.
Many different kinds of paper are created
for a wide variety of applications,including painting, drawing, graphics,
printmaking, and calligraphy.
Papers are available in an extensive
range of sizes, thicknesses, and finishes,as well as in differing degrees of quality,
permanency, and durability.
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A particular type of paper can
often be used for another purpose.
Print papers, for example, can be
used with acrylics, and many
graphics papers are ideal for
drawing.
Keep in mind, however, that
certain papers have poor aging
characteristics and should not beused for permanent fine artwork.
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Types of paper
Watercolour paper
Drawing paper
Print paper
Visualizing paper
specialty paper
Oriental paper
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Uses of paper