US2248056A

US2248056A - Film processing system

Info

Publication number: US2248056A
Application number: US274517A
Authority: US
Inventors: Jesse M Blaney
Original assignee: Individual
Current assignee: Individual
Priority date: 1939-05-19
Filing date: 1939-05-19
Publication date: 1941-07-08
Anticipated expiration: 1958-07-08

Description

July 8, 1941. J. M. BLANEY FILM PROCESSING SYSTEM Filed May 19, 1939 i l I T0 NEXT EEOUP arzaues i Na Hun 9 INVENT R W,

ATTORNEYS Patented July 8, 1941 2,248,056 FILM PROCESSING SYSTEM Jesse M. Blaney, Springdale, Coma, asaignor, by mesne assignments, to the Government of the United States of America, as represented by the Secretary of War Application May 19, 1939, Serial No. 274,517

/ 3 Claims.

This invention relates to film processing apparatus and methods, and more particularly to an apparatus and method of turbulating the liquid through which a long length of film is moved.

Turbulation or agitation of a developing so-' lution through which the film travels is desirable in order to reduce or abolish the directional effact, which is the effect on the film due to the migration within the film structure of one or more of the reaction products of the developing action, the migration being in the direction opposite to the direction of film travel. The effect of this migration is to impair the fidelity of the reproduction. The most commonly experienced directional effect is that due to the migration of halides, for example alkali bromide, some of the bromide or other halides, after formation during the developing, migrating within the gelatin lattice of the film rather than diffusing into the developing solution. As the formation of bromide is greatest in areas of maximum exposure and as bromide retards the progress of the development, the migration of bromide, particularly from the areas of strong exposure into the areas of weak exposure, retards development in the latter areas, thus producing an unbalanced condition between the strong and weakly exposed areas and resulting in a lack of fidelity in the photo reproduction.

The object of the invention is to overcome these objections by a movement and agitation of the developing solution reducing the directional effect and the drift or migration of the bromide or other halides,

In the system of this invention the accumulation of the bromide in the film is avoided by removing it as it is formed and diffusing it into the solution.

Another feature of the invention is the attainment of this result without impairing the movement of the film through the liquid or subjecting it to excessive strains and with an actual assisting of the film movement by a reduction.

of the frictional drag or by applying a positive driving force in the direction of the movement of the film.

Other features of the invention, and its advantages will become apparent from the following description taken in connection with the accompanying drawing, in which:

Fig, 1 is a vertical section through a tank of a film processing apparatus in which the invention is utilized, the section being along line ll of Fig. 2 defining a plane parallel to the direction of movement of the film longitudinally through the tank;

Fig. 2 is a vertical section along the line 2-2 of Fig. 1;

Fig. 3 is a perspective view of part of the apparatus; and r Fig. 4 is a diagrammatic and enlarged view of a portion of the apparatus to illustrate the action of a single jet of the turbulator of this invention.

Referring to Figs. 1, 2 and 3, the film l0, such as the ordinary motion picture film is fed into the tank II at one end, as at A, and is withdrawn at the opposite end, as at B. Within the tank H the film passes around one or more groups of rollers for supporting and guiding the film while it is being treated by the liquid in the tank. Three groups of such rollers are diagrammatically shown, I! and I3 constituting the upper and lower series of rollers, respectively, of

" the first group, N and I! constituting the upper and lower series of rollers, respectively, of the second group and It and I1 constituting the upper and lower series of rollers, respectively, of the third group. N 0 supports or other equipment for or related to these rollers are shown as this invention is not dependent upon the details thereof. These rollers may be constructed, supported and/or driven in any suitable manner.

The incoming film passes seriatim around rollers l2 and I3 of the first group to form a series of substantially vertical loops of film from one side of the tank, as at x, over to the other side of the tank, as at Y. The film then passes over to the second group of rollers, and in like manner passes seriatum around the rollers l4 and I5 thereof to form a series of substantially vertical loops of film from side Y to side X of the tank. The film then passes seriatim around the third group of rollersli and H, in a similar manner as with the other rollers, to form a series of substantially vertical loops of film from side X to side Y of the tank. After passing over th final roller Ii the film leaves the tank.

The apparatus for moving the film through the tank is not shown as this invention is not dependent upon the details thereof. Any suitable film drive may be employed.

The tank II is maintained substantially full of the processing solution, the liquid level LL being near the top of the tank. The upper rollers l2, l4 and II are positioned near the liquid level LL, and while shown as submerged in the solution, may be positioned Just above the liquid level LL. The solution is withdrawn from the tank outlet 20 at or near the tank bottom, and after passing through a pump 2| the solution is conducted to a manifold 22 outside and beneath tank II. Suitable filters, temperature controlling devices and solution replenishing equipment may if desired be incorporated in the pumping system.

Connected to manifold 22 are four

feed pipes

23, 24, 25 and 26 each of which extends into the tank II from the bottom, feed pipe 23 being positioned between the tank end A and the upwardly moving sides of the first series of film loops, feed pipe 24 being positioned between the downwardly moving sides of the first series of film loops and the upwardly moving sides of the second series of film loops, feed pipe 25 being positioned between the downwardly moving sides of the second series of film loops and the upwardly moving sides of the third series of film loops, and feed pipe 26 being positioned between the downwardly moving sides of the third series of film loops and the tank end B. Each feed pipe connects with a cross pipe which extends along the bottom of the tankfrom side X to side Y, the cross pipe connected to feed pipe 24 being designated in Fig, 2 as 24* To each cross pipe are connected two vertical pipes, these pipes being on opposite sides of the tank and extending upwardly nearly to the top of the tank, where the pipe ends are closed. The

vertical pipes connected to cross pipe 24= are and 24, are connected by a plurality of horizontal, vertically-spaced jet pipes, the jet pipes I24 224, 324, 424 and 524, shown in Fig. 2, being the jet pipes connected between

vertical pipes

24 and 24 and thus being the jet pipes which are supplied with solution-from feed pipe 24.' The other jet pipes, shown in section in Fig. 1, are as follows: pipes I23, 223, 323, 423 and 523 supplied with solution from feed pipe 23; pipes I25, 225, 325, 425 and 525 supplied with solution from feed pipe 25; and pipes I26, 226, 326, 426 and 526 supplied with solution from feed pipe 26.

Each jet pipe has a plurality of apertures therein serving as orifices for the liquid passing from the jet pipes into the liquid contained in tank II. The apertures are positioned to direct the liquid which passes through them toward the film adjacent thereto and in the direction in which such film travels. Thus the apertures 3i,

32, 33, 34 and 35 in the respective jet pipes I23,

223, 323, 423 and 523 fed by pipe 23, are upwardly directed and at the angle R from the vertical in the quadrant nearest the upwardly moving sides of the film loops formed by upper rollers I2 and lower rollers I3, while the apertures 4|, 42, 43, 44 and 45 in respective jet pipes I24, 224, 324', 424 and 524 fed by pipe 24, are downwardly directed and at the angle R from the vertical in the quadrant nearest the downwardly moving sides of the film loops formed by upper rollers l2 and lower rollers I3. Jet pipes I24, 224, 324, 424 and 524, fed by pipe 24, also have another series of apertures. This series, consisting of

apertures

46, 41, 48, 49 and 50 respectively, are upwardly directed and at the angle R from the vertical in the quadrant nearest the upwardly moving sides of the film loops formed by upper rollers I4 and lower rollers I5. The jet pipes fed by pipe 25 have double sets of apertures therein similar to the apertures inthe jet pipes fed by pipe 24. The jet pipes fed by pipe 26 have single sets of apertures therein corresponding to the sets of apertures H, 42, 43, 44 and 45 in the jet pipes fed by pipe 24.

The solution is thus forced under pressure up into the manifold 22 where it is distributed to the four

feed pipes

23, 24, 25 and 26. From each feed pipe, the solution, still under pressure, passes through the corresponding cross pipe and up the corresponding two vertical pipes and from them into the several horizontal jet pipes connected between the two vertical pipes. The solution then passes through the apertures in the jet pipes, and, due to the action of the apertures, is projected as a jet at a substantial velocity into the solution in the tank II.

The solution issuing from these apertures creates eddies and turbulences in the solution in the tank II and causes these eddies and turbulcnces to move in the general direction established by the jets, which is toward the adjacent film and in the direction in which that film travels. These eddies and turbulences in the solution thus cause the solution to thoroughly wash and scrub the surface of the adjacent film at the same time that they are moving in a general direction parallel to the direction of film travel.

This action is diagrammatically shown in Figs. 1 and 4, where, although the eddies and turbulences are for simplicity not shown, the general direction of travel of the eddies and turbulences is shown. Broken lines 66 indicate the general direction of travel of the eddies and turbulences created by the solution projected from the jets fed by pipe 23, Fig. 4 being an enlarged view showing only one of the jet forming apertures 31 in jet pipe I2. III and III indicate the adjasent upwardly moving strips of film. The broken lines 6| in Fig. 1 indicate the general direction of travel of the eddies and turbulences created by the solution projected from the jets fed by pipe 24 and which are directed toward the downwardly moving strips of film adjacent thereto.

The result of creating these eddies and turbulences and causing them to contact and move along with the film is to remove and diffuse into the solution substantially all the bromide, or other halide, as it is formed (assuming tank II to be a developing tank) and to substantially eliminate bromide migration, thereby eliminating, or nearly so, the directional effect." In addition, this beneficial result is accomplished without subjecting the film to excessive strains and without impairing the movement of the film through the liquid. In fact, the turbulating action of this invention tends to reduce the frictional drag of the liquid upon the moving film since it reduces the relative movement between the film and theliquid, thereby aiding the motion of the film.

The angle R of the apertures may be any angle from 10 to 45, the preferred angle being about 20. The velocity of the solution as it issues from the apertures preferably exceeds the velocity of the film. With film velocity of 2.5 feet per second (i. e. feet per minute), satisfactory results have been obtained with a velocity at the orifice of 5 to 10 feet per second.

The construction of the turbulator is preferably such that the amount of turbulation created increases with the depth of the solution in the tank. This excess of turbulation at the lower levels tends to compensate for the increased pressure on the gelatin of the film at the lower levels due to the increased statis pressure exerted on the film by the solution at the greater depths.

The increased turbulation at the lower levels is obtained in the construction shown -by feeding the solution up from the bottom of the tank and having the liquid in the lower portions of the jet pipes under greater pressure and by proportioning the sizes of the orifices or apertures in the pipes to use larger size orifices at the lower levels. The pipes may be conveniently reduced in size in the direction of the upward flow of the liquid. This is shown in Fig. 2 where

vertical pipes

24 and 14 reduce in size immediately above the bottom jet pipe I24, the size being progressively reduced in the successively higher pipes.

With the jets progressively reduced in size from the bottom toward the top, the turbulation will be correspondingly graduated according to the static pressures on the film so that the rate of osmosis is substantially uniform throughout the tank despite variations in counter pressure and corresponding variations in the gelatin characteristics. This arrangement in addition provides an efficient turbulation at the surface of the liquid thereby minimizing surface oxidation of the solution.

The number of apertures in the jet pipes may be adjusted to suit conditions. Each jet pipe in the turbulator shown has one aperture for every two loops of film traveling in the same direction past the jet pipe, but any other suitable number of apertures could be employed. The feeding of the solution into the jet system may be from the top or any other portion of the tank instead of from the bottom, the piping and orifices being correspondingly modified to give progressively increasing turbulation toward the bottom of the tank.

It is to be noted that all the turbulator jets are directed against the emulsion or gelatin-coated side of the film as the non-coated side of the film is the side engaging the loop-forming rollers.

It is also to be noted that the turbulator of this invention is applicable to any type of filmprocessing equipment and to any processing tank of a film-processing apparatus. When used in a developing tank it is particularly effective. In the developing tank the specific gravity of the solution is substantially the same as the specific gravity of the liquid (developer and reaction products) contained within the interstices of the gelatin on the film, so that there is practically no osmosis, i. e. no natural tendency for the liquid within the gelatin to diffuse into the liquid in the tank. The film is in motion through the tank, but this motion does not produce any substantial diffusion. Instead the liquid within the gelatin lattice of the film travels within the lattice, although at a lesser absolute forward speed than the gelatin lattice itself. The liquid within the gelatin lattice thus migrates rearwardly relative to the film. As long as this liquid remains within the gelatin it retards further development of the film and its migration impairs the fidelity of the developed reproduction. The turbulator of this invention counteracts the rearward migration of the liquid within the gelatin, the jet velocity being such that the solution impinges upon the film at a velocity greater than the absolute velocity of the liquid in the gelatin; that is, the solution from the jet impinges upon the film at a forward velocity relative to the tank which is greater than the forward velocity, relative to the tank, of the liquid in the gelatin when the turbulator jet is not present. The resultant of these two moving lision of the faster moving jet-impelled liquid with the liquid within the gelatin rapidly drives the latter liquid out from the gelatin and thus difiuses it into the tank solution. This prevention of migration of the reaction products and the prompt diffusion of them into the tank solution promotes development and is obtained without excessive jet velocities, or excessive velocity differences between the film and the liquid. The film does not whip, so that the jet pipes may be placed close to the film, and the power required for operating the turbulator is relatively low.,

The turbulator as shown herein diffuses the liquid within. the gelatin out into the liquid in the tank throughout the travel of the film in the developing tank, the jet velocities, jet orientations and jet pipe locations and spacings being so related to the speed and direction of movement of the film that the film' is subjected to the eddies and turbulences through substantially its entire travel in the developing tank. Thus the reaction products are removed from the film as soon as they are formed, regardless of where the film may be in the tank at the time they are formed. In addition, the turbulator in this manner not only overcomes bromide migration and directional effect, but also promotes development, there-= by enabling satisfactory development to be ob tained with the use of a smaller amount of the necessary chemicals.

The turbulator is simple to construct and install, being essentially made from standard tubing or piping which can be easily cut and fitted together. The jet forming apertures are holes drilled radially into the pipe at appropriate intervals along a cylindrical element of the pipe, the orientation of the jets being controlled by turning the jet pipe about its axis when mounting it; upon the vertical pipes. There are no moving parts to break or wear out in use. The turbulator does not aerate the solution nor create aerial fog upon the film and the turbulator does not subject the film to varying forces which impair the movement of the film and subject it to excessive strains. In fact, the turbulator assists the film movement by reducing the frictional drag of the solution upon the film, and in some cases may even be adjusted to have it apply a positive driving force to the film.

I claim:

1. In a film processing apparatus for long lengths of film, film driving means for moving the film in a prescribed path continuously through a film processing solution with the coated surface of the film carrying the image exposed, and means for substantially reducing the directional effect incident to the movement of the film in the solution and minimizing frictional drag of the solution on said moving film comprising a continuous series of jet orifices arranged in sequence along the film, all of said orifices having their axes inclined toward the film and in the direction of the film travel at an angle of the order of 10 to 45, and means for forcing liquid through said orifices at a linear velocity greater than that of the film and forming a series of similarly directed jets adapted to create eddies and turbulences at the said exposed surface of the film in said solution and to cause these eddies and turbulences to move in a continuous sequence at said surface and in the direction in which the film is traveling thoroughly to wash and scrub said surface and remove and diffuse into the solution the chemical tending to migrate and cause directional effects within said coating, said eddies and turbulences moving solely in the direction of the film and at, substantially the same speed thereof to minimize frictional drag of the solution on the film.

2. Film processing apparatus as set forth in claim 1 in which the film driving means is a series of upper and lower rollers submerged within the processing solution and carrying the film as a series of vertical loops with the coated surface of the film on the outside and out of contact with the rollers and the Jet orifices are formed in a series of pipes extending transversely to the direction of motion of the film.

3. Film processing apparatus as set forth in claim linwhichthefilmdrivingmeansisaseries of upper and lower rollers submerged within the processing solution and carrying the film as a series of vertical loops with the coated surface of the film on the outside and out of contact with the rollers and the Jet orifices are formed in a series of pipes extending transversely to the direction of motion of the film and the lower oriflees are of larger diameter under no greater pressure than the upper orifices.

JESSE M. BLANEY.