The evening star and Newark advertiser. [volume] (Newark, N.J.) 1907-1908, 1907-08-03
W~ATERPRo0FIMG PAPER.
German Process for strengthening Gel
lu1ose Vessels.

Consul T. TT. Norton writes from Chem
nitz that there has been considerable
study of late years in Germany on the
method of treating paper, in its various
forms, SO a. to increase its usefulness
for various Industrial and household. pur-
poses. He furnishes the following partic-
nlars:
There are several methods now in
vogue here for rendering paper and paste
board waterproof which might advanta-
geously be utilized in the manufacture OF
paper and cellulose vessels. One. especially
applied TO cellulose. consists In treating the
sheets with a hot mixture Of asphalt, tuf-
pentine and linseed oil olution of glue.
Another consists of saturating eellulose
articles in Il solution of resin In a mixture
Of petroleum, linseed oil and parafnn OIL
lSolutions of varnish in linseed oil are like
wise employed for rendering a SURFACE
waterproof.
A process which has given good results
Is the following: Articles of paper or Gel
lulose are soaked thoroughly in a solution
of resin soap. They are then immersed IN
a hot bath of zinc Chord, passed between
rollers, are well washed. dried IN q no.
room. treated with paraffln oil anod hnally
run through a colander. The RESULTANT
products are strong, tough and pliable., 4
waterproof ~pasteboard is secured by inn
mersing sheets of ordinary paper in a bath
of nitric acid or the solution of a nitrate,
placing the sheets one on top OF announcer
and then submitting them to heavy pres
sure. / am personally inclined to regard
experimental methods, based upon the fun
damental principle of changing paper into
most success in THU field. Waterproof
cardboard has already been manufactured
by pressing tightly together freshly pre-
pared sheets of the vegetable parchment
The operations In parchmentlzing paper,
Ike those in tanning, are essentially chela-
ieal, and effect a remarkable change IN
with partly diluted %suiphuric acid 1.-TWO
parts of acid of Sc degrees to one part
water) sheets Of pure cellulose paper are
immersed for a few seconds IN the liquid,
then thoroughly washed in water, dipped
III an alkaline solution (ammonin or sodi-
um carbonate) ard washed again. tbs
brief treatment suff1ces to bring aoout tpe
following changes The thickness of the
paper decreases from "a to 81 per cent. Its
specific weight increases In the same ration.
The strength is tripled and even quadru-
pied. There Is a notable increase In homo
geneity and transparency. The product IS
unaffected by boiling water, /. e., Is not
softened and dlsintegrated, as in the case
with ordinary paper! while It has an in
creased affinity for tinctorial substances.
Chemically. the brief exposure to the ac-
ton of sulphuric acid has changed the ex-
terrier of the cellulose fibers to a gelatinous
mass, the so-called amaloid, intermediary
between ~cellulose and dextrin. This geia-
tiDous amyloid binds the hbers SO closely
and intimately together that they form a
continuous mass, which, being totally In
soluble, constitutes a waterproof substance.
With the microscope it is easy to see that
parchment Is a sheet Of cellulose fibers.
each one of which is covered by the thin
transparent coating of amyloid, the inter-
stices or pores likewise being completely
filed with the same substance, 1t is essen
tally q surface action which has taken
place. Ideal conditions of success are rela-
tive thinness of the paper employed and n
complete absence therein of gluey sub
stances and mineral matter. Sulphuric
acid can be replaced by an aqueous solu-
tlon of zinc Chord or an ammoniacal So
luton of cuprous oXid.
In order to render paper vessels water
proof, the essential features of the parch-
mentizing might be applied to their exter-
nal surface. This would involve no ma
terial increase in the strength OF the entire
mass. Another, and possibly more prom
ising method. would be to apply freshly
formed sheets of vegetable parchment UNI
der strong pressure to the inner and outer
surfaces Of the article. 1t will probably
be found that Improvements In the manu-
~facture Of paper vessels, aiming at an in
crease Of tenacity, can preferably BE-
brought about by mechanical operations
quite distinct from the chemical reactions
producing waterproofing. although both Of
these advantages are secured by a single
change in the case of the preparation of
thin sheets of paper parchment.