IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL PARCHMENT, TISSUE, LEATHER, AND FLOOR CLOTH
Year: 1881

page_text: PROVISIONAL SPECIFICATION left by Charles Weygang at the Office of the
Commissioners of Patents on the 24th November 1881.
CHARLES WEYGANG, of 31, Cowper Road, South Hornsey, in the County of
Middlesex, Manufacturers' Agent. "IMPROVEMENTS IN THE MANUFACTURE OF
ARTIFICIAL PARCHMENT, TISSUE, LEATHER, AND FLOOR CLOTH."
This Invention relates to certain improvements in the manufacture of artificial
parchment, tissue, leather, and floor cloth, hereinafter described, and consists
principally in an adaptation of the property which animal glue possesses of being
rendered by treatment with bichromate of potash and alum insoluble and very
tenacious, in combination with animal or vegetablo fibre.
In carrying out my Invention I take any suitable fabric, more particularly
unsized paper or felt, and saturate it with glue, size, or gelatine, after which I hang
it up to dry. When dry I place it in a cold saturated solution of bichromate of
potash and alum in equal proportions, or the alum slightly in excess, and if it is
desired that the product shall be capable of resisting boiling water for a considerablo
time, a small quantity of chrome alum may be added to the solution.
I keep the gelatinized fabric in this solution for some hours, usually from two to
eight, according to the substance or nature of the fabric.
I then transfer the fabric to a similar but hot solution, the temperature being
somewhat under the boiling point, in which I immerse it for some, usually from 10
to 30 minutes, after which I hang it up in a room from which direct daylight is
excluded until it is dry, and then steep it in water until the excess of bichromate
of potash is dissolved out. It is then hung up in a well lighted room, when any
bichromate that may still remain will be decomposed by the light.
When it is desired that the product shall be soft the fabric may be treated with
glycerine, and it can also be glazed and enamelled like parchment.
When glycerine is used it is not necessary to employ chrome alum to enable
it to resist boiling water, as the glycerine indirectly fixes the gelatinous matter
sufficiently.
If I wish to render the product more impervious to water I add to the first
named solution some gum arabic and white soap.
In some cases I add chalk or china clay to the glue, size, or gelatine, by which

page_text: the pores of the fabric are more thoroughly closed and a whiter appearance
obtained, and for some purposes I also employ treacle.
In making artificial parchment, tissue, and leather of a superior quality, I place
the sheets of the fabric as I take them froin the bath of hot bichromate and alum
between sheets of felt until a sufficiently large stack has accumulated, which I then
place in a stove or hot room, after exposure to which for a short time the stack is
placed in a press and the pressure brought to bear on it very gradually. By this
means the excess of moisture is pressed out and the now insoluble compound
composing each sheet will be pressed into a compact mass of great strength.
When it is desired to imitato leather, the fabric may be softened, dyed, and
grained, or embossed like ordinary leather.
The strength of the size, glue, or gelatine, and the nature of the fibre to be
employed depend on the nature of article I intend to produce; thus if I desire to
make an article for common trade uses, such as covering preserves and packing,
I make use of ordinary strong paper unsized or only partially sized, but for stronger
fabrics where flax, or hemp, or similar strong fibre are required, the fibre itself
should be boiled under pressure with a weak alkaline solution sufficiently strong to
dissolve the tannic and resinous matters, and then beaten up in a hollander until it
is thoroughly desintegrated, when it is to be run out on the paper machine or
made as felt in any of the well known ways.
When it is desired to manufacture the article in sheets of great length, commonly
known as endless, I arrange a series of tanks to contain the solutions, &c., with
rollers and endless bearing bands by which the fabric is immersed, raised, pressed,
and immersed again as often as required through the entire series of operations,
and is finally washed and discharged between rollers.
In order to imitate the veins in skins, gut, &c., I crease or crumple the sheets
with the hand or other suitable means before saturating them with size, glue, or
gelatine.
In making floor cloth I proceed exactly as before described except that I use a
very course strong fibrous material. .