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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