No. 786,535. PATENTED APR, 4, 1905. J. E. THORNTON & C. F. S. R OTHWELL, PHOTOGRAPHIC PLATE OR FILM FOR DAYLIGHT DEVELOPMENT AND FIXING,

APPLICATION FILED X AR, 20, 1900. No. 786,535. Patented April 4, 1905. UNITED STATES PATENT OFFICE.

JOHN E. THORNTON AND CHARLES F. S. ROTHWELL, OF MANCHESTER, ENGLAND, ASSIGNORS TO JOHN OWDEN OBRIEN, OF MANCHESTER, ENGLAND,

PHOTOGRAPHC PLATE OR FIM FOR DAYLIGHT DEVELOPMENT AND FIXING,

SPECIFICATION forming part of Letters Patent No. 786,535, dated April 4, 1905. Application filed March 20, 1900, Serial No. 9,463, To all whom, it may concern. an adjacent plate, and by immersion in the Beit known that we, JOHN EDWARD THORN necessary quantity of water an active solu TON and CHARLES FREDERICKSEYMOURROTH tion is formed at the time of development Sep WELL, British subjects, and residents of Man arately for each plate sufficient for develop chester, in the county of Lancaster, England, ing and fixing the negative. have invented certain new and useful Im Figure 1 is a view of plate with the solu provements in Photographic Plates and Films tion containing the developer and fixer coated 55 for Daylight Development and Fixing, of on back and covered; Fig. 2, a modification which the following is a specification. showing the solution containing the developer This invention relates to photographic and fixer coated on the covering or sheath plates and films prepared for use in photo separate from the plate. s graphic cameras for taking camera-pictures. In carrying out the invention we incorpo The object of the invention is to dispense rate the developer and the fixing medium from with bottles of chemical solutions for devel which when dissolved in water a solution is oping and fixing photograph images, also with prepared which effects the double functions the usual dark room, and to provide substitutes of developing and fixing the image, and this which shall be more convenient. we cover with a protective covering. Al Hitherto in the developing and fixing of though we prefer the developing and fixing photographic negatives after removal from medium mixed or incorporated and then ap the camera, it has been the almost universal plied to the plate, the developing medium only custom to prepare two chemical solutions and may be so applied and covered with a pro immerse the plate or film first in one and then tective covering. Any suitable developing or in the other in a dark room from which the developing and fixing medium may be em actinic rays of light have been excluded. We ployed which can be put up and packed with are aware, however, that it has already been the plates in dry form. proposed to apply to the back of each plate The following may be taken as examples of or film the developer by incorporating it with suitable preparations, the proportions being 75 a cement or coating, such as gum soluble in enough for each plate of quarter-plate size. water, which upon the immersion of the plate Developer. --Pyro, two grains, (or hydroqui or film in water dissolves, forming the devel none three grains,) (or metol two grains and oping solution. The operation of fixing after hydroquinone two grains;) sodium carbonate, development has, however, hitherto been al (anhydrous,) tengrains; sodium sulfite, (anhy ways accomplished by immersing it in a sep drous,) ten grains; potassium bromid, one arate solution carried in a liquid form. When half grain. the developer has been attached to the back Combined developer andficer.-Sodium sul of the plate hitherto, it has proved a failure, fite, (anhydrous,) fifteen grains; sodium hy the chief reason for which being that the de drate, (powdered,) nine grains; sodium thio veloping preparation was liable to damage the sulfate, (anhydrous,) twenty grains. Grind face of the adjacent plate when used in maga together and add kachin or pyrocatechin, nine zines and other cases where a number of plates grains. were placed in a pack, and also the developer The developing and fixing medium is made deteriorated by contact with the air. up in the form of a strong solution with Sugar The invention consists in preparing eachsen or dextrin and then applied in one of the fol sitive plate or film (hereinafter called 'plate”) lowing ways: (a) The plate A, Fig. 1, is coat with a developer or combined developer and ed on the back with the solution B, and after fixer applied thereto in suitable dry form and the latter is dry over this is placed a sheet of protected by an air-tight covering, So that the air-tight material C, such as paper, soluble 95 material will not deteriorate itself or damage gelatin, or other material which will prevent

g 786,585 the action of the air upon the developing me developer has been applied to the back of the dium and will prevent it coming into contact plate of damaging the sensitive surface of an with adjacent plates and which will readily adjacent plate by reason of the developing or Separate or dissolve on immersion in water. developing and fixing medium being protected (b) The prepared solution B, Fig. 2, may be by an air-tight cover. To develop, the cov coated upon a paper backing sheath or envelop ered plate may be immersed complete in the D, which covers or protects the plate and water, which dissolves the developer and sof which at the same time serves as an air-tight tens the covering, permitting the latter to be protection for the developing and fixing me removed or thrown away. dium. As applied to rolls the covering ma We are aware that the idea of using a com terial may be attached to the back of the Sen bined developing and fixing solution is not sitive film or a loose paper backing may be new and we make no claim to such a process. wound up with the film and removed or dis The point of our invention is the incorpora carded when the film is cut up into plates. tion of the developer and fixer in some dry The effect of the combination of the devel form attached to or supplied with each sep oping and fixing medium applied to the plate arate plate, as already described, and covered is a great improvement upon what has hith with a protective covering, which dispenses erto been done, because it not only dispenses with bottles of chemical solutions and which, entirely with all chemical solutions in bottles, further, allows development to be carried on (a great advantage to travelers,) but it also in daylight and outdoors at the scene of op renders a dark room entirely unnecessary, as erations, if desired, all without a dark room the plate can pass from the camera after ex or cumbersome cases or devices containing posure direct into a trough or tank in which separate solutions in separate tanks. it is both developed and fixed. By making We believe that our invention constitutes this tank of red, yellow, or other non-actinic a considerable improvement or new step in the glass or transparent celluloid.the progress of art of photography and that it will do much development and fixing can be easily seen and to simplify the present troublesome opera the plate removed when desired. It is, how tions. It will reduce the time occupied there ever, not essential to watch the progress, as in and enable the operator to ascertain the 3O by combining the fixing with the developing results of his exposures on the spot without operation no serious result will happen to the waiting till he returns home or carrying cum picture should the plate be left in the tank bersome developing apparatus, and, further, rather too long. . dispenses with all troublesome measuring and By our invention it becomes possible to re mixing of chemicals. As a consequence it 35 move the plate from the tank in daylight as will increase public interest in the art and Soon as developed, whereas this was not pos lead to a more extensive practice of it. sible hitherto, because if the plate was removed What we claim as our invention, and desire from the developing-tank to a separate fixing to protect by Letters Patent, is tank in daylight the image became fogged by 1. In a photographic plate or film for use the light during transference from one tank in a camera the combination with the base to the other, and all devices hitherto proposed plate or film of a sensitive coating on one side, in which the two tanks were inclosed from a developing medium in a dry form applied daylight by some box or covering chamber to the other side, and a protective covering other than a dark room were unsatisfactory, applied over the developing medium substan 45 as accidental mixing of the solutions fre tially as described. quently occurred and spoiled the image. Af 2. In a photographic plate or film for use ter the plates have been developed and fixed in a camera, the combination with the base outdoors or away from home we prefer to plate or film of a sensitive coating on one side, leave the necessary operations of Washing to a developing and fixing medium in a dry form free the plate from all traces of chemicals applied to the other side, and a protective cov until the operator returns home. In order ering applied over the developing and fixing to facilitate this and prevent any injury to the medium substantially as described. plates in the meantime, a grooved box or In witness whereof we have hereunto signed equivalent device may be employed into which our names in the presence of two subscribing 55 the wet plates can be placed without touch witnesses. ing each other. The box is closed by a lid J. E. THORNTON. or door and may afterward be used as a wash C. F. S. ROTHWELL. ing-tank without removing the plates there Witnesses: from. This invention, further, overcomes J. OWDEN OBRIEN, the objection hitherto experienced when the HARRY BARNFATHER.