US170360A - Improvement in vegetable parchment - Google Patents

Description

Urrnn STATES PATENT OFFICE.

AMBROSE G. FELL, OF NEW YORK, N. Y., 'ASSIGNOR TO HIMSELF, WILLIAM H. PHELPS AND WILLIAM-H. SMITH, OF SAME PLACE.

IMPIROVEMEHNT IN VEGETABLE PARCHMENT.

Specification forming part of Letters Patent No. 170,360, dated November 23, 1875; application filed March 31, 1875.

To all whom it may concern Be it known that I, AMBROSE G. FELL, of the city, county, and State of New York, have invented a new and Improved Vegetable Parchment, and that the following is a full,

. which is hereinafter described.

The material or substance com monly known as vegetable parchment, while possessing some of the qualities of parchment, is extremely brittle, and liable to fracture underordinary circumstances, so as to limit its useful application to a great extent. By my invention I produce a Vegetable parchmen'tthatnot only possesses all the qualities of the substance heretofore known by that name, but it is rendered exceedingly tough and pliable, making it useful for every purpose to which parchment and thin leather are now used.

My process consists in subjecting the paper, after it has been treated by sulphuric or other acid or otherwise, to a compound solution consisting of glue, tungstate of soda, acetate of lead, and glycerine, in such proportions as will render the gelatine of the glue insoluble and tough by the action of the tnngstate of soda upon it, and at the same time render the paper flexible by means of the glycerine. The permanency of this flexibility is due to the insoluble condition of the gelatine of the glue.

This solution retains the gelatine as long as the temperature is above 180 Fahrenheit, but on cooling precipitates it in a leathery elastic condition, which cannot be again dissolved on "again subjecting it to the said temperature.

The above-described bath is applied to the vegetable parchment while heated to said temperature of 180 Fahrenheit. The parchment being thus treated is next submitted to a solution of pyroxyline, the action of which upon the parchment is as follows: The sudden reduction of temperature precipitates the gelatine in the paper in the condition desired, while the mutual decomposition of the acetate Pb O s rbo so The first solution above described may be of the following proportions, from which I have obtained good results, viz: Water, one hundred gallons; glue, eighty pounds tungstate of soda, two and a half to four per cent. of the glue acetate of lead, ten per cent. of the glue; glycerine, three to five per cent. of the glue.

These ingredients are thoroughly dissolved at 180 Fahrenheit or more, and the paper is immersed in the solution from two to three hours. It is then removed, and the surplus liquid returned to the bath in any suitable way. It is next immersed for a few minutes in a bath of pyroxyline solution, highly dissolved, the bath consisting of about-Water, one hundred gallons, and pyroxyline solution, from ten to fifteen gallons. This solution in bath form is maintained at the ordinary temperature, and the material, when taken from it, is well worked in water, or a weak solution of sal-soda (carbonate of soda;)- but if plenty of water is used, and the paper is well washed, the use of the soda is unnecessary.

It is obvious that the exact proportions of the solutions above named, and the time of treatment, may be varied to some extent Without departing from the spirit of my inventionas, for instance, .I might employ compounds which, in their chemical action, might yield the desired element, and thereby produce the same effect as though that element had been employed in its free condition.

After the material has been thus subjected to the chemical baths above recited, it may bedriedby passing it between heated calender-rolls, which will give it a smooth and desirable surface.

The product produced by the process substantially as above described possesses not onlythe well-known characteristics of natural skin or leather, but it is in many respects superior to it. It cannot be torn by any ordinary-manipulatioxiflt may be elastic or not,

' as desired; it is extremely pliable; waterproof and translucent; admits of dyeing in any desired color; hot water and boiling does notmaterially change its characteristics; exposure to the action of flame will not ignite it, but will cause it to shrivel and give out an odor like burning skin; its translucency is uniform throughout its substance, and not in blotches; its general appearance is likely to deceive persons who are experts in leather and skin, and they would be apt to pronounce it leather or skin upon examination; it is stronger than leather, and, to a greaterdegree, indestructible. In fine, the microscope or chemical analysis will alone determine that it is composed of a vegetable base gelatinized and collodionized.

Having thus described my inventiomwvhat I claim as new, and desire to secure by Letters Patent, is-- 1. As a new article of manufacture, artilicial parchment, consisting of gelatinized and collodionized fiber, substantially as described.

2. The process hereinbefore described ifOI' treating vegetableparchmentwith a solution of glue, tungstate of soda, acetate of lead, and glycerine, and with a solution of pyroxyline, in the proportions and in the manner substantially as and for the purpose described.

Witnesses:

H. L. WATTEN'BERG, G. W. PLYMPTON.