US346224A - Thomas c - Google Patents

Description

UNTTED STATES.

THOMAS C. ROCHE, OF BROOKLYN, ASSIGNOR TO E. & H. T. ANTHONY & CO

PATENT ()FFICE.

OF NEV YORK, N. Y.

COMPOSITION FOR HOLDING PHOTOGRAPHIC PAPER ON lTS SUPPORT, &c.

SPECIFICATION forming part of Letters Patent No. 346,224, dated July 27, 1886.

Application filed October 28. 1885. Serial No. 18l,155. No specimens.)

To all whom, it may concern.-

Be it known that I, THOMAS C. ROCHE, of Brooklyn, in the county of Kings, in the State of New York, have invented an Improved Composition for Holding Sensitive Photographic Paper on its Support During the Exposure of the Paper in the Camera, of which the following is a specification.

My composition consists of the following ingredients, combined in the proportions stated: rubber, three ounces; pitch, one-half ounce; solvent for the same, one pint. The solvent may consist of benzole, turpentine, bisulphide of carbon, or any of the solvents of pitch and rubber; but I prefer to use benzole. I dissolve the rubber in the benzole or other solvent, and when a thorough solution is effected I thin it to the desired consistency with the solvent, which in the present case is benzole.

I then add the pitch and allow it to stand,with occasional agitation,until a complete solution of the pitch is effected. This compound I designate as compound No. l. I then prepare compound No. 2, which consists of the following ingredients, in the proportions stated: rubber, three ounces; benzole, sixteen ounces; yellow beeswax, two drains. I dissolve the rubber in the benzole, and after thinning it to the desired consistency with the benzole I add 0 the yellow beeswax and allow it to dissolve.

I then mix compound No. 1 and compound No. 2 together, employing either equal parts of each or mixing them in any other desired proportion.

In lieu of the common glass plate ordinarily used within the camera for carrying or supporting the sensitive film, I employ a support consisting of a thin plate or sheet composed of wood, metal, paper,card-board, or other suita- 0 ble material, the surfaces or faces of which are smooth, and if the material is of a porous, absorbent nature I fill the surfaces thereof with a suitable filling or varnish. Upon the face or faces of this support, when dry, I spread a thin 5 coating of the composition above described by means of a brush, or in any other convenient manner, and allow it to dry until the volatile matters have escaped. The pitch and the bees Wax added to the rubber render the mixture permanently tacky, so that it will possess suf- 5o ficient adhesiveness to attach itself to the surface of the sensitive paper, but will not penetrate the sensitive paper or be absorbed thereby, nor will it in any manner injure or permanently affect the paper. The sheet of sensitized paper is applied by its back to the face of the above-described support, and the face of the paper is then gently rubbed, so as to cause the tacky coating of the support to grasp, hold, and smoothly support every part of the sensitive paper, rendering it impossible for any portion of the paper to curl, wrinkle, or get out of shape. The support, with its attached pa per and tacky material interposed between the face of the support and the sensitive paper, is now placed in a plate-holder in the ordinary manner and introduced Within the photographic camera, and the sensitive paper is exposed to the light fortaking the picture in the usual way, after which the plate-holder and support are removed from the camera for the development of the picture by the usual method, the paper being removed from its support by lifting one corner of the paper and stripping it off from the support. The composition applied to the support is of a nature that will admit of removing the paper from the support without removing the composition along with it. It will also retain its tacky quality, so that one coating of the tacky composition may be used repeatedly and will last a long time. WVhenever any portion of the tacky facing be comes worn away or exhausted,it may be readily renewed by the application thereto of a fresh portion of the tacky composition.

It is obvious that either compound N o. 1 or compound No. 2 will be efficient in retaining the sensitive paper on its support, so that I do not limit or confine myself to a mixture of these two compounds. It is also obvious that I may substitute for the pitch or wax a fixed oil or any substance that will render the support permanently tacky.

By the employment of the above composition the sensitive photographic paper is held upon its support with sufficient firmness to permit of the manipulation of the paper in the plate-holder and camera; but the quality of the tacky surface secured in my composition is such as to permit of the ready removal of the sensitive paper from the tacky surface without removing any appreciable quantity of the composition from the photographic-paper support.

I do not claim, broadly, as my invention the construction of a camera-support having its face or faces provided with a tacky substance for grasping and holding the sensitive photographic paper upon said support, as hereinbefore described, as said device is the inven tion of Edward Anthony, of New York, who has applied or is about to apply for a patent thereon.

My invention herein described is intended to relate to and include only my said compo sition of matter.

What I claim, and desire to secure by Letters Patent of the United States, is

1. The herein described composition for the camera, the same consisting of rubber,"

pure beeswax, pitch, and a solvent, in about the proportions stated.-

holding sensitive photographic paper on its THOMAS C. ROCHE.

Witnesses: O. SEDGWIOK,

A. E. BEACH.