US419779A

US419779A - Gustav roller

Info

Publication number: US419779A
Authority: US
Publication date: 1890-01-21
Anticipated expiration: 1907-01-21

Description

UNITED STATES PATENT OFFICE.

GUSTAV KOLLER, OF VIENNA, AUSTRIA-HUNGARY, ASSIGNOR OF ONE-HALF TO FRANZ PGNNINGER, OF SAME PLACE.

PROCESS OF TREATING GLUE AND G ELATlN E MOLDS.

SPECIFICATION forming part of Letters Patent No. 419,779, dated January 21, 1890.

Application filed June 8, 1888. Serial No. 276,505. (No specimens.)

To all whom it may concern.- Taking wax casts which fully meet all ar- Be it known that I, GUSTAV KOLLER, cheintistic requirements from glue or gelatine ist, a subject of the Emperor of Austria-Hunmolds has so far proved impossible, as the gal-y, residing at Vienna, in the Province of molten wax acts on the mold and dissolves 5 Lower-Austria, in the Empire of Austria-Hunthe superficial portion of the same, so that, gary, have invented certain new and useful notwithstanding the fact that the molds are Improvements in the Process of Treating Glue varnished, only blunt and inaccurate casts and Gelatine Mol'ds; and I do hereby declare can be obtained. the following to be a full, clear, and exact de- By my improved process of treating and 1o scription of the invention, such as will enable preparing glue and gelatine molds, presently others skilled in the art to which it appertains to be described, the drawbacks hereinbefore to make and use the same. mentioned are fully overcome. By this pro- The object of the invention is to provide a cess the outermost or superficial layer of the new and improved process for treating glue molds, or the whole mass of them, is rendered I5 and gelatine molds for casting works of art, resistant against being highly heated without the molds being adapted for making serviceprejudice to the sharpness of the forms and able plaster and wax casts and permitting of to the elasticity of the molds, so that plaster pouring alloys of a low melting-point directly casts may be allowed to coolwithin the molds, into them. the molten wax can be heated to a tempera- 20 The invention consists of treating the surture of nearly 212 Fahrenheit, or molten alface of the mold with strong oxidizers and afloys the melting-point of which is not much terward exposing the same to the action of above this temperature may be poured into the light. the molds without alteration of their surface.

The elastic glue and gelatine molds, on ac- In this way it is possible to use elastic glue 25 count of their cheapness of manufacture or gelatine molds when making wax casts or and of the sharp negatives they afliord of the fillings necessary in casting brass upon acore. most artistic designs, have superseded in all The necessary resistance is given to molds branches of reproducing plastic objects the by treating their surface with energeticallyformerly-used plaster-of-paris molds. oxidizing substances. For this purpose an 0 The glue and gelatine molds as heretofore aqueous solution of anhydrous chromic acid, constructed have a serious drawback, which chromates or permanganates of alkalies, or becomes very apparent when taking plaster nitrate of silver can be used to great advanor stucco casts from the molds or when retage. After having coated the molds one or moving wax casts. more times with one or the other of said solu- 5 35 As is well known, plaster-of-paris and all tions they are exposed to daylight, or, if neccompositions containing this substance heat essary, to an artificial light, and so allowed to when hardening in the molds, so that the updry, which completes the process. The oxpermost layer of glue or gelatine mass is idizing layer which is thus formed imparts to melted. The preventive measures heretothe mold astrong resistance against heat with- 9 '40 fore taken against this, by coating the molds out impairing in the least the neatness of the t with oil varnish and adding alum to the plasforms. By applying one or more concentrated tic mass used for the cast, do not affect this solutions of the said strong oxidizers to the surdrawback, as the varnish stands a relatively face of the molds a greater or less number of small number of casts only and as the additimes and by exposing the molds a longer or 5 tion of alum hastens the solidification of the shorter period of time to the action of light superficial portion of the cast, thus admitting a thicker or thinner layer of the oxidizing subof its being taken out of the mold before it is stance is obtained, according to the special retoo highly heated,but causing crystals to form quirements. After the molds are provided on the surface of the cast, which, although with a layer of the oxidizing substance the 50 they do not render it wholly unserviceable, molds maybe coated with a thin layer of varmar its aspect. nish.

When it is not desirable to use the material of unserviceable molds again,the glue or gelatine maybe dissolved in one of the aforesaid solutions instead of dissolving it in water, as usual. The molds are formed in the usual way from the solution of glue or gelatine thus obtained, and afterward they are exposed to the action of. the light, so that the whole mass of the mold is oxidized and rendered resistant against heat. It has been found by experiment that an aqueous solution of anhydrous chromic acid gives the best results. By applying this liquid from two to six times to the surface of the molds and subsequently exposing the molds to the action of light during six hours, molds are obtained which do extremely well for plaster or stucco and wax casts, as well as for work on reliefplates and statuary. It is obvious that molds of the desired kind, owing to their resistance against heat, can be directly used for taking casts in alloys the melting-point of which is not much above 212 Fahrenheit.

The glue or gelatine material of dried-up or nnserviceable molds in which the superficial layer only has been treated with the said oxidizers can generally be used again. To this end the molds are out to pieces and said pieces are boiled in water, and finally the mass is caused to pass through a sieve, so that the 30 oxidized portions will be retained by the sieve,

as the said oxidized portions are less soluble in water than genuine glue or gelatine.

Having thus fully described my invention, I claim as new and desire to secure by Letters 35 Patent l. The herein-described process for treating glue or gelatine molds, consisting in treating the surface of the molds to strong oxidizers and afterward exposing the same to the ac- 40 tion of light, substantially as described, and for the purpose set forth.

2. The herein-described process for treating glue or gelatine molds, consisting in dissolving the glue or gelatine in an aqueous solu- 45 tion of energetic oxidizers, then forming the molds in the usual way, and finally exposing the same to the action of light, substantially as described.

In testimony whereof I affix my signaturein 5o presence of two witnesses.

eUsiAv KOLLER.

Witnesses:

EDMUND J USSEN, OTTO SCHIFFEN.