About
Paper
P
Factors Other Than Price
rice is only one aspect of
what's appropriate. Design is
just as important. All people
involved in the process should have
the same values about quality for
a particular job.That applies to
vendors and suppliers as well as
designers and clients. Consider the
image you want to project.You are
a designer and you want your
designs to look good. If you're running a two-color job—a novel with
woodcuts, for example—you might
want a rough text stock. But if
you're running big four-color pictures, you need a paper
that can take a lot of ink.
If your best designs are
Selecting the right paper is
put on the wrong paper,
more complex than spendthen you might as well go
ing- a lot or a little money.
down the street and sell
donuts.
Instead of automatically
Other than
choosing the highest qualiprice and design, the other
ty, or even the highest
major consideration in
quality you can afford, you
paper selection is the
should figure out the most
expectation of the end
user.To satisfy your end
appropriate paper for your
needs.
users, you must ask yourself how
they judge quality; keep in mind, too,
that quality means different things
to different people. For an advertiser, it might be how many sales an ad
generates. For a museum curator, it
might be how exactly a catalog
matches the art in a show.
Real quality lies not in any single standard but in putting together
a concept on a sheet of paper that
will do the job for your client.Thus
the only possible paper choice is
the sheet that will accomplish this
best. Anything less—or more—is a
waste of time and money.
No matter what —quality is
not free. Your customers pay for it,
and they want their money’s worth
when they see ink hit the paper. It's
up to you to make sure they get it.
Finish
Finish refers to the way the
paper is surfaced.There are two
classes of paper finishes: smooth
and rough. Smooth finishes generally
reproduce artwork with better
detail and more accurate color
because the paper surface reflects
light more directly, without scattering.That's why papers with smooth
finishes are usually used to print
color halftones. Smooth finishes
can be applied to paper either by
Paper Characteristics
When choosing the most appropriate paper, several
characteristics have to be considered simultaneously:
1. Smooth or rough finish? 6. How strong?
2. Coated or uncoated?
7.What color?
3. low glossy?
8. How bright?
4. low opaque?
9.What basis weight?
5. Iow thick?
10.What fiber content?
calendering (in which the paper is
smoothed over a polisher) or with
coatings.
Rough finishes scatter light,
which makes images look a bit fuzzier and colors (especially solids) a bit
muted. Rough finishes come in many
different patterns, including grids,
lines and pebbles.You can create
interesting effects with rough
papers, but you have to be careful
about detail and color. As for detail,
be aware that small ink dots may get
lost in the paper pattern.Type with
fine serifs may look broken, and
halftones with fine detail will tend
to plug up. Also realize that rough
finishes tend to absorb more ink,
which leads to greater dot gain and
loss of detail.You can compensate
for this by using inks that do not
spread out much. Such inks are used
in waterless printing, for example.
Coating
A paper's coating refers to the
chemicals applied to a paper surface
to smooth it out. Paper may be
coated or uncoated, and coatings
themselves can be glossy or dull.
Coated papers take ink well and
reproduce color more accurately
because the smooth finish reflects
light directly, and the coating keeps
ink from sinking into the paper
matrix.When you want to reproduce high-quality color, where detail
and color saturation are important,
use coated papers.
Coating is an expensive
process, however, so coated papers
cost more than uncoated papers.
If you want reasonable color reproduction but can't afford coating, you
might try supercalendered paper.
This is paper that has been polished
and smoothed on special equipment.
It takes color ink better than roughfinished paper, but costs less than
coated stock. Many Sunday supplements are printed on supercalendered paper.
Design to Fit
One criterion for the best
size for a printed piece is
the size that wastes the least
amount of paper.You can
custom order different
papers in oddball sheet sizes,
but you'll usually get a better
paper price if you buy sheets
that are already trimmed to
standard sizes.
Paper
Standard Sizes
Type
(in inches)
Bond
8.5 x11, 8.5 x14,
11 x 17, 17 x 22,
17 x 28, 19 x 24,
19 x 28, 22 x 34
Text
23x35,
Book
Cover
17.5 x 22.5,
25
19
23
35
20
25
x
x
x
x
x
x
38, 26
25, 23
35, 25
45, 38
26, 23
38, 26
x
x
x
x
x
x
40
29,
38,
50
35,
40
About
Paper
Gloss
Gloss is the amount of
shininess reflected by a paper's
(cont.) surface. Paper gets its gloss from the
amount of smoothness on the surface, which can be engineered by
polishing the paper surface or by
applying a coating. Polished papers,
such as supercalendered, are glossier
than unpolished papers, but they are
not nearly as glossy as coated
papers.
Coated papers come in a range
of glossiness. At the low end of
glossiness, a kind of wash coating
can be applied, which seals the surface of the paper but does not add
much gloss itself. When the paper
surface is sealed, ink dries more on
top of the paper instead
of sinking in.This preserves dot
structure better, so colors look
brighter and details are finer. Wash
coating is not very glossy, however,
so if you want even better
reflectance (and, hence, better color
and detail), then you should look for
more gloss.The next level of glossiness is mattecoated paper,
There is another downside to glossy
which is shinier
paper. Past a certain point, a glossy finish can
than wash-coatmake the eye tired.That's why books with a lot
of text are rarely printed on glossy stock. If
ed but not as
you're contemplating a job with a lot of color
shiny as dulltext, you must balance the conflicting needs of
coated (also
color fidelity against readability. Many designers
called suede or
compromise in these situations by selecting a
velvet) paper.
dull-coated or matte-coated paper, which has
Even
shinier is
enough gloss to reproduce photos well, but not
gloss-coated,
so much gloss that the eye gets tired.
then ultragloss
and finally castcoated, the shiniest paper of all.With
each level of added glossiness, the
paper surface reflects more light
more uniformly. Ink holdout is better too, so colors look brighter and
more saturated with finer detail.
Unfortunately, the heavier the coating, the more costly the paper.
Caliper
Opacity
Opacity is a measure of the
amount of light blocked by the
paper. It is sometimes referred to
as show-through.The amount of
opacity a paper has depends on
many factors (see the factors in the
box below. )
Papers with high opacity do not
let much light shine through.Thus,
the printing on one side does not
show through on the other side. If
you're going to print two-sided
designs with dense ink coverage,
you'd better choose a paper with
high opacity.
More Opaque
Thick paper
Groundwood paper
Coated paper
Rough-finished paper
Dark-colored paper
Paper Types
More Show-Through
Thin paper
Free sheets
Uncoated paper
Smooth-finished paper
White or light-colored
paper
Caliper is the measure of the
thickness of a single sheet in points.
Note that caliper points (1/1000 of
an inch) are different from typeface
points (1/72 an inch)—just one
more happy remnant of printing history.The caliper scale measures
thickness, while the typeface scale
measures height.
Very heavy cover papers called
board stock (tag, bristol, index,
poster board) are sometimes measured in ply.These papers are manufactured by laminating several layers
(or plies) of paper together, rather
like plywood. Ply is not really a standardized measurement, but many
mills use this term to specify their
board papers. If you want to know
exactly how bulky a board stock is,
ask for a measurement in points.
About
Paper (cont.)
Basis Weight
Strength
There are two categories of
paper strength: internal strength and
surface strength. Internal strength is
engineered into the paper and
depends on how the fibers in the
pulp bond together.
You need to make sure your
paper is strong enough to withstand
the stresses of printing and end use.
But unless you're a paper engineer,
it makes more sense to place the
responsibility for paper strength
with your suppliers. You are
responsible, however, for fully
informing your suppliers about the
stresses your paper must withstand.
So tell your paper supplier exactly
how you plan to use the paper,
including your plans for using ink,
presswork, folding, perforating,
binding, gluing, labeling, mailing and
special finishing (varnishing,
foil-stamping, embossing, scoring).
Papers can be made to withstand
great stress, but not all papers are
made to handle all stresses.
Surface strength
Surface strength, as opposed to internal strength, has to do with the way a
paper holds up when ink and heat are applied.The most important surface
strengths to be aware of are:
1. Pick strength.This type of strength allows paper to resist the tendency of
sticky ink to pull off pieces of paper coating and fiber; important in any kind of
high-quality printing, but especially color work.
2. Coating strength. Similar to internal bond strength (above), this strength
helps paper coating resist delaminating away from the paper substrate.
Delamination results in blisters.
Color
Color is achieved through the
use of dyes or bleaches added to
paper to produce different hues.
When you're choosing paper color
(even different shades of white),
always look at printed samples.The
color of the paper affects the color
of the inks laid upon it because
most offset inks are transparent. If
you're concerned about how your
inks will look, especially if you use
colored paper or custom-mixed
ink, ask the printer to drawdown a
sample so you can see for yourself.
You can also ask the printer to
splice some paper samples onto
your regular press run.
Grade
Grade is the brightness of
blue light reflected from the paper
surface.The American Paper
Institute has set brightness
standards industry-wide to
determine paper grades. A #1
sheet reflects 85 percent or more
blue light; a #2, 82 to 84 percent;
a #3, 78 to 82 percent; a #4, 74
to 78 percent; and a #5, 70 to 74
percent. Since paper buyers typically
have other quality expectations for
these different grades of paper
(for example, people expect a #1
sheet to be ultrasmooth), the mills
do respond to these expectations.
But paper grade is technically
determined only by brightness.
internal strength
The most important kinds of internal strength to know about are:
1. Mullen strength.This helps paper resist bursting; important if a paper is going
to be punctured as it is when a design is stapled, wire- or comb-bound, perforated or hole-punched.
2.Tear strength.This helps paper resist tearing; important if a paper is used for
packaging (especially bags); also important for web papers, w-hich experience a
tendency to tear as the paper snaps off the printing blanket and is drawn along
the line of press units.
3.Tensile strength.This characteristic helps paper resist stretching; important in
web papers.
4. Bond strength.This type of strength keeps paper fibers bonded together;
important in web papers, which experience stress going through the drying
ovens.
Basis weight is defined as the
number of pounds per one ream
of five hundred sheets.When mills
say a cover paper is 80-pound, they
mean that five hundred sheets
weigh 80 pounds. Different papers,
however, are measured with
different-sized sheets, so it's hard
to compare a cover paper, for
example, with a book paper. Cover
sheets measure 20" x 26" while
book papers measure 24" x 36".
That doesn't mean you have to buy
your papers at the basic sheet size,
of course.You can buy many
different sizes of sheet, but for
purposes of figuring the basis
weight, each type of paper has a
recognized, standardized size.
Pulp Content
Pulp content refers to the
fiber content of a paper. Paper can
be made from almost any fiber that
bonds together when wet. Papers
presently on the market are made
from wood, cotton, wheat, hemp,
kenaf, rice, old paper, beer hops,
banana plants, even grass clippings
from golf courses.
Most publication papers, however, are made from wood into two
basic types: groundwood papers
and free sheets. Groundwood paper
pulp is made by grinding up wood
chips, which leaves the lignin
unchanged. Lignin is a brownish
organic compound that "glues"
together the cellulose fibers in trees.
Lignin adds opacity and bulk to
groundwood papers, but it also
reduces brightness and whiteness.
Free sheets are made by chipping
the wood and treating it with
chemicals to remove the lignin.
Lignin-free papers are smoother
and brighter than groundwood
papers.