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Edward A Dawe.

Paper and its uses : a treatise for printers, stationers and others online

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side of the paper. As the coating is slightly thicker
at the edges of the web, these edges are trimmed off,
and the web goes forward for one or more journeys
through the super-calender rolls. Dull art and papers
with a specially high finish receive slightly different
treatment, the surface in all cases being made perfectly
smooth in order that the finest half-tones may be
printed successfully.

Chromo papers are usually coated on one side only,
and the body paper is stouter than that used for art
papers. Used largely for lithography, the paper must
be as free from stretch as possible. This is obtained
as described in the chapter on the reduction to pulp,
by using soft fibres, sharp beater knives, and cutting up
quickly, this treatment producing what the papermaker
knows as " free " pulp, as distinguished from " wet "
pulp, which, owing to prolonged treatment, combines
with some of the water and actually becomes " wet."
The surface of chromo papers may be dull or highly
glazed.

Surface coloured enamelled papers are used largely
by box-makers, for labels for packets of various
commodities, and also as end papers for books. The
coating and body paper are thinner than for art papers,
the colour is obtained by the use of a pigment or an
aniline colour, and the coating and after-treatment are
exactly as in the case of art papers. Flint-glazed
surface papers are used for the same purposes as
surface-enamelled papers, and have a hard burnished
surface obtained by a stone burnisher travelling back-



$O PAPER AND ITS USES

wards and forwards across the surface of the paper as
it emerges from the calender rolls.

Boards may be coated in the same way as paper,
provided the boards are not too thick. The thicker
qualities are either coated on a modified machine, the
looping being impossible, or coating by hand is resorted
to. The boards are obtainable as one- or two-sided,
with different degrees of surface, and with different
coloured coatings. Coated boards are sometimes made
by pasting coated papers to ordinary middles, and
finishing by plate rolling.

Thin box boards for use as cartons for small goods,
such as cigarette packets, are coated with a coloured
coating in the manner already described.

Coloured cloth-lined cards are first manufactured as
pasteboards, and are afterwards coated on the cloth
side with the coloured coating, two applications being
necessary in many cases to obtain the desired thickness
and surface. Plate-glazing is the means of imparting
the ordinary surface to this class of cards.



CHAPTER X
MISCELLANEOUS PAPERS

BLOTTING, DUPLICATING, COPYING, TISSUE, COVER,
GUMMED, WRAPPING

THERE are so many varieties of paper which are only
occasionally encountered that it is better to present
the whole of them in alphabetical arrangement (see
Chapter XVII.), and in this section to give a longer
description of a few representative papers.

Blottings and filter papers are very similar in
appearance and manufacture, their definite purposes
being to absorb moisture, and to filter suspended matter
from solutions respectively. The description of blotting
paper manufacture will cover both varieties. The office
of blotting paper being to absorb ink, the raw material
is chosen with a view to obtain the most efficient fibre
for the purpose, soft muslins, too soft for writing papers,
making excellent blottings. The preliminary treatment
of the rags has been described already. Beating is
carried out as quickly as possible, sharp knives being
used to cut the fibres into short lengths, and not to bruise
or beat the fibres more finely. As many fibre ends as
possible must be absorbing on a given area at one
time, and the shorter the lengths to which the fibres
are cut, the greater the efficiency of the blotting paper,
within certain limits. Certain after-treatment of the
fibre is resorted to, to produce as soft and absorbent a



52 PAPER AND ITS USES

fibre as is consistent with the necessary cohesion, but of
course manufacturers prefer to keep special methods to
themselves. At the paper machine little or no shake
is given, and very light pressure is given throughout,
just sufficient to smooth the paper down. Strength is
not aimed at, but the paper must be strong enough to
resist the handling it will receive in ordinary use.

Most blotting papers are made in demy, with a
standard weight of 38 Ib. per ream of 480 sheets.
There are blottings made of wood pulp, but these are
far below the rag papers in efficiency. Soda wood
pulp makes a very fair blotting paper, but sulphite
wood is not so absorbent as soda pulp paper. Wood
pulp blottings are usually made in thin substances for
interleaving diaries and similar books, where repeated
use will not be required. Enamelled blotting papers
are made by pasting enamelled (coated) papers to the
ordinary blotting paper and rolling down. These
blottings can be obtained in a variety of colours, both
the blotting and surface paper being varied in colour.
Coloured blottings are made of the usual ingredients,
with added colouring matter.

Duplicating, impression, and multi - copying are
different names for the same papers. They are used
for the various duplicating machines of the cyclostyle
and mimeograph patterns, where a number of copies of
written or typewritten matter is required quickly. A
very thin ink is used, and it is necessary that it should
be absorbed very speedily. These papers are practi-
cally unsized, contain a large proportion of esparto for
the better qualities, and a certain quantity of mechani-
cal wood in the cheaper sorts. A very large range
of these papers is obtainable : laid or wove, white,
cream or tinted, with rough or moderately smooth
finish. For copies produced by the same process, where



MISCELLANEOUS PAPERS 53

a signature has to be appended, or when the form serves
as a blank for written additions, a half-sized paper
is obtainable in similar qualities and tints.

Tissue papers are strong, thin papers, the best
quality being made from hemp or rag fibre, well beaten,
with no loading or sizing, made in blue or cream,
usually double crown in size ; other qualities are made
from mixtures of rag, chemical wood, and straw, in
various proportions and in various weights. Tissues
serve a large number of purposes, as wrappings for
high-class goods, therefore they must be strong and
free from chemicals, for fly-leaves for the protection
of engravings and prints, and also for the basis of
carbon papers which are used for obtaining a simul-
taneous copy of written or typewritten documents.

Copying papers are similar in all respects to tissues,
but some varieties have a small amount of mineral
matter added to increase their efficiency. Made in
cream wove, blue wove, and buff, put up in reams of
500 sheets, copying papers are used for press copying
correspondence which has been made in copyable ink.
Special typewriter ribbons are supplied, but most
typewritten matter copies without trouble. The leaf
of the copying book is damped, the excess of moisture
removed by an absorbent sheet, the document inserted,
the book closed, and pressed in the copying press. By
this means copies of correspondence are preserved for
reference. Copying paper is also made up in rolls for
copying machines which carry out the damping and
copying automatically.

Cover papers are obtainable in many qualities,
colours, and sizes. The materials used in their manu-
facture run through the whole range of papermaking
fibres, the best qualities having a good proportion of
rag fibre, while the low grades have some quantity



54 PAPER AND ITS USES

of mechanical wood, but there should be little if
any mineral matter present, as strength is an important
feature. The finish of the papers is smooth, moderately
rough, or rough ; the colours tend to browns, greys,
slates, and dark greens, but a fair number of more
delicate shades can be obtained, and some of the
reds are most effective. The substances of cover
papers run from 1 8 Ib. to 56 Ib. demy per ream of
480 sheets, so there is sufficient variety from which
to select paper to suit any job.

As covers for booklets, price lists, pamphlets, etc.,
cover papers are regularly used, and for other purposes
there has arisen a demand for the darker shades. The
army of photographers, professional and amateur, have
employed cover papers as mounts, either in the form of
cut mounts or as photographic albums. For these
purposes the range of substances has been extended,
the heavy papers being made in card thicknesses. In
making papers for photographic mounts a very
necessary quality is that the paper shall be absolutely
free from chemical substances likely to affect the
photographic prints mounted upon them. Colour
prints are mounted on neutral cover papers for
insertion in magazines or books, but when publications
have extensive and growing circulations, the time and
cost of mounting militate against this very effective
method of displaying illustrations.

Embossed cover papers are made and finished in the
usual manner, and run through special rolls having the
pattern engraved upon them. Papers for embossing
must possess good strength or the embossed design will
not stand handling, or the paper may break when
embossed.

Pamphlet cover papers are thick tinted papers,
made in a very pleasing variety, serving as programme



MISCELLANEOUS PAPERS 55

papers and for much jobbing work, as well as for the
purpose for which they were originally intended.

Covers for exercise books are usually glazed on one
side only (M.G.). This should be the outside of the
book, and any printing should be executed on the
smooth side. " Pressings " are the papers usually
employed for such purposes, a cheap cover paper
obtainable in various colours, weights, and sizes.

Gummed papers are made in a variety of qualities,
colours, and substances. The papers range from the
thinnest printing to thick enamelled paper, and the
thickness of the coating of gum is varied to meet all
requirements. Many colours of paper can be procured
ready gummed. To obtain a satisfactory gummed paper
three things have to be studied : body paper, gum, and
thickness of coating. The inherent fault of gummed
papers is the tendency to curl, but the extensive manu-
facture of non-curling gummed papers has done much
to remove this bugbear. By adopting a paper which
is affected but little by atmospheric changes something
is accomplished in the minimising of curling, but by an
ingenious breaking of the gummed surface non-curling
is secured. When the coating is dry, the paper is
drawn over a steel edge to break the homogeneous
film of gum into innumerable fragments. In absorb-
ing or parting with moisture (the cause of curling) the
small particles can only act as individuals instead of
combining and curling. Any kind of paper can be
gummed, but the thinner the paper the more effective
its adhesion when used as a label. When a label, slip,
or any printed matter has to cover other printed
matter, the paper must be thicker and opaque enough to
prevent the matter beneath from showing through.

Wrapping papers are of many kinds, of various
substances and colours, and are varied, too, in surface.



56 PAPER AND ITS USES

The materials used range from the strongest to the
weakest from hemp rope to mechanical wood and
include jute in the form of old gunny bags or sacking,
hemp refuse, old rope and string, waste card cuttings,
old paper, and wood pulp refuse. The substance ranges
from 38 Ib. to 160 Ib. per ream of 480 sheets in
double imperial, the colour from " white " to a very
dark brown, and the finish from highly glazed both
sides to a rough air-dried surface.

Strong materials are boiled under pressure for
several hours, lime being employed for hard papers,
and soda for softer papers. The fibres receive but
little washing, going on to the beaters, where the
stronger fibres are first reduced and the softer materials
added later. Loading, colouring, and size are added,
and the paper made on the Fourdrinier. Air-dried
browns are specially tough, very leathery, will stand
a great deal of folding, and when packing and unpack-
ing of parcels is required the extra cost is easily
recouped. Cylinder-dried browns are dried on the
paper machine, and the papers are not so elastic as
air-dried papers of the same substance. Glazed browns
are usually lighter in colour and cleaner in appearance
than the ordinary wrappings, and usually contain a
large proportion of wood pulp. Kraft browns may
be described as glazed browns, as they are sometimes
finished with a glazed surface both sides. A special
kind of pulp is used for krafts, wood being digested
at a comparatively low pressure with soda solution, the
boiling being prolonged. The fibres are loosened, and
reduction to pulp takes place in the edge runner
(kollergang) instead of the beating engine. By this
means the fibres are drawn out, not cut up, and very
tough papers can be made, fully entitling the papers to
their description as " kraft " (German for " strength ").



MISCELLANEOUS PAPERS 57

Special wrappings which will not discolour the
goods packed in them are necessary for packing such
fabrics as cotton goods, this quality being made without
added colouring matter. Ream wrappers are sometimes
thick common papers, serving as protective coverings
only, being heavy but with little strength. Some
papers are packed conscientiously, the manufacturer
or stationer recognising the fact that a valuable paper
demands a good packing paper. The use of poor
paper is strange, seeing that the printer is charged
for the wrapper at the rate quoted for the contents.



CHAPTER XI
CARDS AND CARDBOARDS

IN the chapter devoted to the manufacture of boards
a brief description of the method of the production
of each variety is given. Pulp boards, triplex (or
multiplex), and pasteboards are there described, and
coated boards of various sorts are included in
Chapter IX.

Pulp boards are frequently looked upon as soft
and flexible, and many may be so described, but for
card index work a stiff snappy card, thin in substance,
is required, and as pasteboards and other cards made
up of layers tend to split when subjected to much use,
pulp boards are essential for that class of work. The
boards which most closely resemble ivory boards in
appearance will be found the most suitable for system
use. A smooth writing surface, free from spots and
other imperfections, is required, but the cards should
be easy to rule and print. It is impossible to manipu-
late successfully cockled or wavy boards in ruling,
printing, or cutting, so time will be saved if the
selection of boards for index cards is made from the
kinds which can be obtained perfectly flat. The softer
kinds of pulp boards are excellent for a great deal of
advertising matter, folders, post-cards, and for jobs for
which something stouter than the usual tinted papers
is required. Where rigidity is demanded pasteboards
will be found of service. Some boards are made with



CARDS AND CARDBOARDS 59

grey middles and poor facings, but it is possible to
obtain a good class of boards at a moderate price, and
it is far more satisfactory to keep a stock of material
of good appearance than to obtain the lowest quality
possible. White cardboards should be rigid, of good
colour, smooth, and should be so well sized as to be
suitable for post-cards or similar work. Pasteboards
can be obtained in various substances, being described
as three-sheet, four-sheet, etc., but there is no point
system in card thicknesses, as one maker's six-sheet
will be tUe same as a four-sheet of another manufacturer.
A very fair range of colours can be obtained in paste-
boards, but if a special colour is desired a making
order is frequently necessary to ensure sufficient of the
special facing paper.

Triplex boards are not made in the same variety
of thickness or colours as pasteboards. It is not
possible to build up the substance in triplex and to
dry the web successfully in the thickness of the heavier
pasteboards, but it is possible to procure very good
triplex boards with the attributes specified for paste-
boards.

The better qualities of cardboards will be found
suitable for most classes of printing, even for half-tone
work, but if three-colour blocks are to be printed,
coated boards are necessary. Chromo boards, one- or
two-sided, are obtainable from three- to twelve-sheet in
substance, and on these any class of work will stand
well. Owing to the burnished surface of these boards
show cards keep clean for a much longer period than
when ordinary cardboards are used, and frequently
varnishing can be dispensed with if enamelled boards
are not exposed to weather. Coated boards must be
handled with care at all times, as the surface is
sensitive to grease and moisture, notwithstanding its



60 PAPER AND ITS USES

dustproof tendency. Cloth-lined and cloth-surfaced
boards are used for club cards, being very durable and
folding well. The white side should always be the
inside.

Wholesale stationers keep a large and varied stock
of cut cards, plain, round cornered, gilt edged, embossed,
plate sunk, with fancy borders and fancy surfaces. A
list of stock sizes will be found on page 140, but this
list does not refer to every variety of card. Some
kinds, such as ivory cards, are stocked in all the
regular visiting and business card sizes and jnultiples
of the same, and others in the usual ticket and
correspondence card sizes. Reference to th' stock
book of any maker will serve as a guide in ordering
for stock or for special purposes. Post-cards, plain and
with printed fronts, are procurable in a variety of
qualities, and often prove very useful to small printers.

The standard size for boards of all kinds is royal,
25 inches x 20 inches.



CHAPTER XII
DURABILITY OF PAPER

PAPER is used for many publications and jobs of an
ephemeral character, and for these the permanence of
paper is never in question. On the other hand,
ledgers, leases, agreements, share certificates, must be
upon paper which is to all intents and purposes per-
manent and capable of resisting a good deal of handling.
Printed records, too, must be preserved on paper that
will, with ordinary care, be indestructible.

The constituents of paper, as shown in the first
chapter, are vegetable fibres, mineral filling, colouring
matter, and vegetable or animal sizing. The fibres
producing the paper which approximates most nearly
to a pure cellulose material, with the minimum of
chemical and mechanical treatment, are, of course, the
best possible. Classified with that in view, cotton,
flax, hemp, chemical wood, esparto, and mechanical
wood is the order of merit. Cotton is, more than any
other material, the ideal fibre. It contains 91 per cent,
of pure cellulose, has a comparatively small amount of
incrusting matter, and its fibre is easily bleached, and
easily prepared for papermaking. Consisting as it
does of seed-hairs, cotton is a free fibre from the first.
It consists of a long tube, of dumb-bell section, with a
tendency to twist upon itself. Prolonged beating
produces numerous fibrillae, and the softness of the
original fibre is preserved until over-beating is reached.



62 PAPER AND ITS USES

*>

The twisting, the division into fibrillse, make for
strength, good felting, and, with the softness in addition,
the best and most durable papers are those of cotton.

The flax fibre is a bast fibre. Its yield of pure
cellulose is 70 to 80 per cent. The fibre consists
of a thick walled canal, which is easily seen in the
unbeaten state. Beating tends to crush and remove
the early characteristics. The fibres are regularly
rounded or polygonal, and easily split into numerous
fibrillse, the ends of the fibres beat out into bunches
of small fibres, and these, together with the nodules
which occur on many of the fibres, produce strength
in the paper. The flax fibre is straighter than the
cotton fibre, and so linen papers are stififer and harder
than cotton papers.

Wood, produced as fibres by chemical means,
consists largely of tracheids, long ribbon-like cells,
which are easily broken into shorter lengths. It is not
possible to subdivide the fibres longitudinally by pro-
longed beating. This only tends to shorten the fibres.
Hence Mitscherlich, 1 or similarly produced wood pulp,
gives strong tough papers, unattainable by those pulps
which are strongly bleached and much reduced. The
tracheids, being smooth and flat, do not tend to make
soft papers. But, blended with rag or esparto fibres,
excellent papers may be produced. Only 50 per cent,
of fibre is produced from the original wood.

Esparto gives a smooth, cylindrical fibre, pointed,
short, with small canal. Being small, the fibres do not
receive much treatment in beating. Separation and
cleaning are the principal ends of the preparatory
stages. Esparto is, to the papermaker, synonymous

1 Mitscherlich process : boiling for a long period under low
pressure, afterwards disintegrating the fibres by means of the edge
runner.



DURABILITY OF PAPER 63

with bulky papers. The best of printing papers, litho.
papers, and featherweights are composed largely of
esparto. It blends well with the preceding fibres,
and especially with chemical wood for printing papers.
Unfortunately esparto is liable to deterioration, and
thus is not suitable for permanent papers. Its yield
of cellulose is low 42 to 47 per cent.

Mechanical wood is lowest in the scale of paper-
making materials. Chemically it is impure ; struc-
turally it consists of chips and fragments, seldom
complete fibres. Ground into short lengths, it consists
usually of short bundles of short pieces of fibre. It
does not felt well, and requires the addition of other
fibrous material to hold the pulp together as paper.
Ten to 40 per cent, of chemical pulp is usually added
to mechanical pulp to make it more lasting and less
brittle.

In 1898 a committee appointed by the Society
of Arts reported upon the deterioration of papers after
extensive investigation. Their conclusions hold good
to-day, and may be summarised in the next five para-
graphs.

The deterioration of paper may be by discoloration
only, or disintegration may also occur. Discoloration
may be caused simply by the action of the atmosphere,
and is to be seen in the margins of books and in
coloured papers. The outer margins of books are
more susceptible to oxidation than the interior, and
in gaslit rooms most books will in time suffer from
discoloured margins. Chemical residues from the
manufacturing processes, if left in the paper, will
bring about changes in colour, engine-sized papers
being more liable to change than papers which are
tub-sized. Papers which contain esparto, straw, or
mechanical wood, will in chemical laboratories certainly



64 PAPER AND ITS USES

become discoloured, as aniline and other coal-tar bases
stain the papers yellow or pink. There are but few
colouring matters which are absolutely fast, therefore
most tinted and coloured papers will change in time.

Loss of strength may be due to impurities in paper,
such as residues of the chemicals used in the preparation
of the pulp, to the impurities in the pulp itself, or to the
use of gas as the agent for lighting and heating. The
use of china clay for the improvement of the surface of
the paper and for the increase of opacity, tends to
weaken the paper, not by any chemical reaction, but
merely by rendering the paper less resistant to wear.
The attainment of extreme whiteness by bleaching
is sometimes obtained at the expense of durability,
as products are sometimes left in the fibre which will
cause deterioration and discoloration of the paper.

The classification of the fibres has been referred
to, and the four classes are : (i) cotton, flax, hemp ;
(ii) chemical wood ; (iii) esparto and straw ; (iv)
mechanical wood.

For written documents of permanent value the
paper should be all rag fibre, without starch and
loading, tub-sized with gelatine. For printed books
to be preserved as of permanent value, not less than
70 per cent, of the fibre should be rag, the loading
should not exceed 10 per cent, as shown in the ash
of the paper, and the sizing should be effected by
not more than 2 per cent, of resin.

The wearing qualities of paper are affected by
the method of manufacture as well as by the con-
stituents. Blotting paper, which is an all-rag paper,
will soon wear away, owing to the fact that the fibres
are cut short and loosely held together without sizing.


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Online LibraryEdward A DawePaper and its uses : a treatise for printers, stationers and others → online text (page 4 of 12)