Improvements in Mucilages, Sizes, and Adhesive Compounds.
Year: 1891

page_text: Date of Application, 29th Dec., 1891-Accepted, 30th Jan., 1892
COMPLETE SPECIFICATION.
Improvements in Mucilages, Sizes, and Adhesive Compounds.
I, CHARLES MICHAEL HIGGINS of 168 & 170 Eighth Street Brooklyn, in the
County of Kings, and State of New York, in the United States of America,
Manufacturer, do hereby declare the nature of my invention for IMPROVEMENTS
IN MUCILAGES, SIZES AND ADHESIVE COMPOUNDS, and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement :-
I form my adhesive compound of water, borax and dextrine dissolved together,
and to these afterwards add ammonia, or other alkali, as hereinafter set forth. The
water is preferably heated to boiling, or nearly so, the borax then added and
dissolved, and the dextrine is then introduced and stirred in, and the heat continued
until a perfect solution is obtained. The borax combines chemically with the
dextrine and causes it to dissolve more perfectly and remain in solution afterwards
without separating or precipitating, as generally happens to a great extent with all
ordinary solutions of dextrine in water. In addition to this, the borax prevents
fermentation and decay, and retards, but does not absolutely prevent molding.
When the solution of borax, dextrine and water is effected as described, and
preferably after the solution has cooled to the temperature of air, I add a small
quantity of some alkaline solution, preferably caustic soda or ammonia, and stir the
same thoroughly into the solution. This addition produces a peculiar reaction,
having the effect to suddenly thicken, or partly coagulate or jellify, the solution in
a remarkable degree, and thus greatly increases the body and viscosity of the
mucilage, and enhances its adhesive qualities in an extraordinary manner. The
alkali particularly if ammonia is used, also acts to entirely prevent mold or decay,
which would not be effected by the borax alone, even if used in a saturating
proportion.
The peculiar reaction named is usually accompanied by a sudden and positive rise
in the temperature of the solution, usually amounting to six or more degrees
indicating an energetic chemical action in the mixture.
The thickening effect due to the alkali is practically permanent, and disappears
only very gradually after a long period of time. In fact, so far as I have observed
it never disappears altogether, but its gradual reduction produces an important and
unique advantage, for when the mucilage is exposed to use in the stand it practically
remains at the same degree of viscosity, notwithstanding the thickening effect due
to evaporation, for the reason that the loss of body, due to the gradual reduction of
the viscous property named, is almost balanced by the increase in body or density due
to evaporation, so that this novel mucilage will remain a very long time at more
nearly a uniform thickness when exposed to evaporation than any other adhesive
compound of which I am aware.
The
The proportions of the ingredients may vary a good deal, according to the density
and viscosity of the mixture required, and according to its particular uses.
best proportions for an ordinary strong mucilage are, dextrine and water in equal
parts, and borax of the dextrine. These parts are by weight, and to the liquid
mucilage thus made, to in volume of ammonia at 20 degrees Baume, or
caustic soda lye at 40 degrees, by the same scale, should be used to produce the
increased viscosity and adhesiveness named. Of course, when the alkalies arc
weaker, more may be used, and less when they are stronger.
The borax, however, may vary from 1 to of the weight of the dextrine, and
the alkali may vary from or less to 1 or more of the volume of the mucilage,
and the water can vary according to the density of the mucilage required, as will be
understood.

page_text: The viscous effect described cannot be obtained if caustic alkalies are used in
combining with the dextrine instead of the borax, but it can be obtained when
boracic acid is substituted for the borax, so that a boron compound, or some
equivalent thereof, is an important element of my invention. The carbonate or
bicarbonate of soda will not give the effect of the biborate of soda, but it is probable
that some other mild salt analogous to borates or biborates, or some other acid
analogous to the boracic, may be found to be an equivalent.
Other coagulating or thickening agents may be used besides the caustic alkalies.
The alkaline salts and alum may be so used. Most of the alkaline salts, however,
such for instance as the carbonate of soda, have only a slight thickening effect when
added to the compound of dextrine and borax. Alum, however, when used with
the alkalies, increases the coagulating or thickening effect very materially. A
saturated aqueous solution of alum may be used for this purpose, preferably in a
volume about equal to the volume of the alkaline solution used, but this proportion
may vary. The alum is preferably added first to the solution of borax and dextrine,
and the alkali afterwards added, when a strong thickening effect takes place, the
mucilage becoming extremely viscous and adhesive. The alkaline solution, may,
however, be added, before the alum solution, but the effect is not so good.
If a solution of dextrine and caustic alkali be first made, and borax afterwards
added thereto, no thickening effect is produced, whereas if the borax is first
combined with the dextrine and caustic alkali afterwards added, a positive
thickening effect is obtained.
The mucilage herein described, may, of course, be dried into a solid granular gum
which may be dissolved in water as required.
In some cases, the dextrine and borax may be combined together in proper
proportions in the form of dry powders which can afterwards be dissolved in hot
water, and to the solution thus formed a little ammonia or other alkali may be
added, which will form a very viscous and adhesive mucilage in a very simple and
ready manner, and at a very slight cost.
This
I am aware that a composition has heretofore been shown in the United States
Patent No. 244,200, of 18×1, consisting of 92 per cent. dextrine, with three per cent.
borax, and five per cent. alum, the whole being dissolved in cold water.
composition is quite distinct from my composition of dextrine, borax and water,
as it is essential to my composition that the borax be in a large proportion
relatively to the dextrine, such as about from to of its weight, and that
the mixture be heated or boiled as set forth, in order to effect the chemical
combination of the borax and the dextrine. Where the borax exists in only a
small proportion, as in the Patent referred to, and where no heat is applied to
the mixture, only an imperfect, murky solution and combination of the borax
and dextrine with the water is effected, and a large part of the dextrine will
eventually precipitate in a sedimentary or flocculent form. On the contrary,
where the proportion of the borax is relatively large, and where the two are
combined with the water by heat, or boiling, as in my invention, a perfectly
clear and permanent solution of the dextrine in the water effected, which will
not afterwards precipitate or deposit as is the case with most all the solutions
of dextrine usually made.
The limiting heat or temperature at which the chemical combination of the
dextrine and borax takes place seems to be about 90 degrees Fahrenheit, for if the
solution is made several degrees below that, the combination does not seem to take
place. The most perfect combination and solution seems to be effected at a
temperature between 150 degrees and the boiling point, which is the range within
which I prefer to work.
Where, however, an alkali is added to the compound of borax and dextrine, a
high temperature does not seem to be essential, that is, the addition of an alkali
seems to promote the combination of the borax with the dextrine so that this will
take place at a lower temperature.
Hence a comparatively clear and viscous solution of the dextrine and borax may

page_text: ne made cold, or nearly so, when the alkali is afterwards added to the compound,
but a much clearer solution and a much stronger thickening effect is produced if
the borax and dextrine solution is made at a temperature of 90 degrees, or more,
and the alkali afterwards added.
Of course the thickening or coagulating agents can be added to the mucilage in
powder instead of solution, but the solution is obviously preferable.
Either the white or yellow dextrines may be used to good advantage in this
compound, the white dextrines making a much more viscous compound than the
yellow dextrines. Glucose or grape sugar will combine and act in almost exactly
the same manner as the dextrines, and may be considered the equivalent or sub-
stitute therefor in this compound, but the sugars will not make a good adhesive
compound as compared with the dextrine. Mucilage made as described herein with
one of the sugars in place of the dextrines will be inferior in cementing power, and
quite hygroscopic, whereas, the mucilage made as described with the dextrine, is a
very quick drier and not affected by atmospheric moisture.
I wish to be understood that where I name borax in the claims, I mean, of
course, to include the boracic acid, or its equivalents, as set forth in the Specifica-
tion, as being the equivalents of the borax.
My improved adhesive compound may also be used for sizing for paper or
textile fabrics, and also for size in kalsomine, or other washes or paints and for
many similar uses for which it may be found suitable.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1st. An adhesive compound composed of water, dextrine and borax in the
proportions specified, and combined by heat or boiling, substantially as herein set
orth.
2nd. An adhesive compound composed of water, borax, dextrine, and a thickening
or coagulating agent, substantially as herein set forth.
3rd. A viscous adhesive compound formed of dextrine and borax dissolved in
vater, with an alkali added thereto substantially as herein set forth.
Dated this 29th day of December 1891.
W. P. THOMPSON & BOULT,
Agents for the Applicant.