US1967889A

US1967889A - Machine for developing goffered moving picture films

Info

Publication number: US1967889A
Application number: US473218A
Authority: US
Inventors: Kitroser Isaac
Original assignee: Keller Dorian Colorfilm Corp
Current assignee: Keller Dorian Colorfilm Corp
Priority date: 1930-08-05
Filing date: 1930-08-05
Publication date: 1934-07-24
Anticipated expiration: 1951-07-24

Description

I. KITROSER July 24, 1934.

MACHINE FOR DEVELOPING GOFFERED MOVING PICTURE FILMS Filed Aug. 5, 1930 2 Sheets-Sheet l INVENTOR Jaw m BY M K 4 ATTORNEY July 24, 1934. l. KITROSER 1,967,889

MACHINE FOR DEVELOPING GOFFERED MOVING PICTURE- FILMS 2 Sheets-Sheet 2 Filed Aug. 5, 1930 INVENTORI M W BY W g Y ATTOR Patented July 24, 1934 PATENT OFFICE MACHINE'FOR DEVELOPING GOFFERED MOVING PICTURE FILMS Isaac Kitroser, St. Cloud, France, assignor to Keller-Dorian Colorfilm Corporation,

New

York, N. Y., a corporation of Delaware Application. August 5, 1930, Serial No. 473,218

7 Claims.

My invention relates to a machine adapted to be used for the development of goffered motion picture films whereby the precise and careful treatment necessary in developing such films may 6 be efiectively and uniformly carried out in connection with large scale operations;

The object of my invention is to provide a machine whereby the above purposes may be satisfactorily and effectively accomplished and more 10 particularly whereby the dissolvent action of the materials used in developing the films may be controlled with the greatest precision.

It has been known previously that films in natural colors having a goifered base as, for example, made by the Keller-Dorian process, can be obtained by the known method of photographic inversion whereby a direct positive can be obtained. The present invention is concerned with providing a new machine for carrying out the production of such photographic films. In the development of goffered motion picture films, a special developer yielding an exceedingly fine silver grain and reducing considerably the photographic diffusion which occurs in ordinary emulsions is required. It has been found, for instance, that this developer requires the presence of one or more solvents of any one of the silver halides present, as for example, silver bromide. Such solvents may, for example, be an alkali thiosulfate as, for

example, sodium thiosulfate NazszOs, a cyanide of an alkali metal as, for example, potassiiun cyanide KCN, ammonium hydrate NH4OH, or a sulpho-cyanide of an alkali metal, such as sodium sulpho-cyanide NaSCN, or any other chemical compound capable, in the process of development, of reducing, progressively, the silver content of the emulsion. There results, consequently, in the process, that this developer has double action on the emulsion, as follows:

40 (1) A developing action analogous to the customary development of ordinary negatives. This action has the effect of increasing the contrast of the photographic image, which contrast proceeds rapidly during the first minutes of the developing action, then less rapidly, and finally very slowly. Consequently, this phase of the developing action need not be regulated with great precision, since a variation of 10% from the time of development gives only a very slight variation in the contrast of the image,a variation imperceptible to the eye.

(2) A dissolvent action which has the effect of reducing the thickness of the sensitive coating of the emulsion. This action must be controlled 55 with very great precision in order to have it stopped at the right moment. It is found that a difference of more than 1% in the estimate of the amount of time required reveals itself very clearly to the eye.

Consequently, there are present in said process two chemical actions, one of which being a reaction of equilibrium, has the characteristics of being highly sensitive to time, temperature and agitation. All these factors in the development must, therefore, be extremely precise, and should be capable of being regulated in the course of the development.

Also, as the developer becomes enriched as the process of development proceeds, by the alkali bromide present, for example, the time of develop- 7o ment, as a result, becomes longer and longer, and it is necessary to compensate for this, either by changing the period of time to which the film is subjected to the developer, or by the addition of an accelerator of the development to the develop 7 ing bath.

Accordingly. the machine made in accordance with my invention is provided to accomplish these purposes as above referred to.

While my invention is capable of embodiment in many different forms, for the purpose of illustration, I have shown only one form of the same in the accompanying drawings, in which:

Figs. 1, 1a constitute a longitudinal vertical section of an apparatus made in accordance with my invention it being understood that the right side of Fig. l connects with the left side of Fig. 1a; and Figs. 2, 2a constitute a horizontal section of the same it being understood that the right side of Fig. 2 connects with the left side of Fig. 211, Fig. 2a being shown on a reduced scale.

In the apparatus as shown in the accompanying drawings, I have provided the following general features, for example:

(1) There are provided one or more developing tubs communicating with a large reservoir by one or more pumps, which cause an energetic circulation during the development, the reservoir serving to decrease the degree of change in the chemical composition of the bath during the course of. the development.

(2) The tubs are preferably made of a material which is not attacked by the chemical agents present as, for example, glass, ebonite, nickel, or an alloy which is not attacked by ammonia in 5 the case of the developing tubs, nor by the acid which is used in the inversion tubs.

(3) The developing tubs are preferably equipped with agitators. The time of development depends, to a very appreciable extent, upon the degree of agitation. Consequently, it is desirable that the action of the pumps and the speed of the agitator shall be substantially constant.

(4) The developing tubs and the reservoir are preferably protected by insulation to maintain a constant temperature, the reservoir tub being equipped, in addition, with a heater and a cooler of the bath electrically controlled by a thermostat, so as to maintain exactly constant the temperature of the bath during the development.

(5) The period during which the film remains in the bath can be automatically increased by reason of the enriching of the bath with the alkali bromide, for example.

. (6) In order to regulate the process by compensating for the alkali bromide and for the evaporation of the ammonia from the bath, means is provided for introducing an additional solution with an accelerating action as, for example, ammonium hydrate, or an alkali carbonate such, for instance, as sodium carbonate, etc., which is controlled by the speed of the machine, and which introduces the liquid into the reservoir during the course of the development.

The factors of temperature, agitation and speed of the film and chemical compensation in the bath, should be capable of being regulated at will. For example, the temperature should be capable of being regulated so as to be maintained between temperatures of 15 and 25 C. Furthermore, the developing tubs should be carefully closed to reduce the evaporation of the ammonia from the developing bath.

Referring to the accompanying drawings, I have shown in detail a machine containing these elements. In the drawings I have shown two developing tubs, 1 and 2,'made of suitable resisting material as, for example glass, in order to resist the attack from the chemicals therein. These are, preferably, heat insulated. The film in the process is fed from a magazine 3, the film being fed therefrom'by two geared

rollers

4 and 5, which are not only geared together, but. which are driven by means of a beveled gear 6, from a beveled gear 7, on a main driving shaft 8, which is driven at any desired speed by means of pulley 9, band 10, and pulley 11, from an electric motor '12. From the

rollers

4 and 5 the film passes on to a guide roll 13, carried on a shaft 14, connected by worm gearing 15 to said main driving shaft 8. From this point the film passes over, alternately, ,a succession of guide rolls 16 on a shaft 17 which is adapted to be raised and lowered in two lateral vertical guides 18 and 19 in the tub 1, and a succession of guide rolls 20 which are located on the shaft 14. From the tub 1 the film then passes forward to a succession of guide rolls 21 on a shaft 22, driven by worm gearing 23 from the main driving shaft 8, alternately with a succession of guide rolls 24 on a shaft 25, located in the tub 2 and carried in two vertical guides 26 and 27 in said tub. The time during which the film remains in the

tubs

1 and 2 depends upon the distance between the rolls on the shafts 14 and 17 in tub 1 and the rolls on the

shafts

22 and 25 in tub 2. This distance increases regularly in the course of the development by reason of the fact that the shafts 17 and 25 are supported respectively by bands 28 and 29 which respeca The

tubs

1 and 2 are provided respectively with

agitators

40 and 41 which are driven by pulleys 42 and 43 respectively from any suitable source of power to stir the liquid energetically during the v development.

The liquid for the developing

tubs

1 and 2 is delivered thereto respectively by means of

pipes

44 and 45 in which there are located respectively

powerful pumps

46 and 47 to supply to said tube a continual circulation of liquid from a heat insulated reservoir 48. The return of the. liquid from the

tubs

1 and 2 is by means of pipes 49 and 50, leading back to the reservoir 48. The developing'and accelerating solution thus fed to the reservoir 48 and'which, for example, may be comprised of a solution having the following composition:

Glycin para-oxy-phenyl-amido-acetic acid- 6 gr. Anhydrous sodium sulfite 15 gr. Ammonium hydrate NH4OH 25 cubic cm. Potassium bromide 10 cubic cm. of a solution of 10% strength is supplied to the reservoir from a vessel 51, having a valved outlet pipe 52 leading to the reservoir, which pipe 52 contains a rotary measuring device 53 having pockets 54 therein for measuring the liquid as it is supplied to the reservoir 48. This measuring vessel 53 is driven by worm gearing 55 from a shaft 56 having a beveled gear 57 meshing with beveled gear 58 on the shaft 8. The speed of supply of the liquid from the vessel 51 is arranged at such a rate as to compensate for the change in the chemical composition of the developer as the developing action proceeds in the tubs'l and 2. In the reservoir 48 there is provided a heating coil 59 containing any suitable heating liquid the temperature of which is determined by means of an electrical heater 60 heated by the resistance in an electric circuit 61. The electric circuit is automatically made and broken by means of a circuit breaker 62, controlled by magnet 63 from a thermostat 64, located within the tub 1. In order to also provide means for automatically lowering the temperature there is provided in the reservoir 48 also a cooling coil 65 adapted to contain any suitable heat inter-changing liquid, the temperature of which is controlled by refrigerating unit 66, of any desired character arranged to be operated by an electric circuit 67. This circuit 67 is arranged to be made and broken by means of a circuit breaker 68 controlled by magnet 69 from a thermostat 70 inside the tub 1. A substantially constant temperature will be maintained within the

tubs

1 and 2 and the reservoir 48 as the heating and cooling units, including the thermostats 64 and 70, will lessen and practically eliminate the variations of temperature therein. By this means, the temperature therein can be kept constant to within 1 degree Fahrenheit variation. In practice, the thermostat 64 will interrupt the circuit 61 when the temperature rises above 66 degrees Fahrenheit. Also, the thermostat 70 will interrupt the current in the circuit 67 when the nately over a succession of guide rolls 77 on a shaft 78, carried in vertical guide rolls 79 and 80 and additional rolls 81 on said -shaft 75. The length of time which the film remains in the tub 71 is determined by the position of the shaft 78, which is controlled by

bands

82 and 83, passing upwardly over guide rolls 84 and 85 on a shaft 86 adapted to be rotated by crank 87. This tub 24 carries an acidulating bath containing any desired acid, as for example, sulphuric acid, in water the strength of which may be from 1% to 2% by volume of sulphuric acid therein. The treatment in this tub serves to remove from the film the minute drops of developer and to stop the process of development. It will be noted that the

tubs

1 and 2 and 71 are located in a dark room 88, and when the film emerges from the tub 71 it passes therefrom over a roll 89, makes a loop 90 laterally so as to pass within a light shield 91 and thence out thru a slit 92 behind said shield in the wall of the dark room 88; thence the film proceeds to an inversion tub 93, having the usual valved inlet and outlet pipes, over a roll 94, after t which it is received upon a guide roll 95 on a shaft 96, driven by worm gearing 97 from the main shaft 8. Here again the film passes by means of repeated loops over a succession of rolls on the shaft 96 and on a shaft 98, movable vertically in

guides

99 and 100, the elevation of which is determined at will by means of

bands

101 and 102 passing over

pulleys

103 and 104 on a shaft 105, arranged to be moved by crank 106, an arrangement which is substantially the same as that provided in tub 71. This inversion tub 93 is for dissolving to the desired extent the silver which is developed in the

tubs

1 and 2, the tub 93 for this purpose being provided with a solution of the following composition:

For each liter of water- Potassium permanganate KMnOr 4 gr. Sulfuric acid H2804 20 cubic cm.

From this point the film passes into a wash tub 107 constructed the same and with the sameequipment as the tub 93, except that the tub 107 is smaller in lateral dimensions and has fewer guide rolls than the tub 93. This wash tub 107 is provided with a body of water for washing the film as it passes thru the same. From this point the film passes into a bleaching tub 108 constructed the same and provided with the same equipment as the tub 107. This bleaching tub 108 contains a bleaching bath comprised of a solution of one part by weight of sodium bi-sulphite dissolved in one part by weight of water.

From this point the film passes into a wash tub 109 containing a body of water, which tub is constructed and equipped the same as the bleaching tube 108. Then the film passes into a darkening tub 110 constructed and equipped substantially the same as the tub 93 except that there is no roll here corresponding to the roll 94, and except that the tub 110 has one side thereof, 1ll, constructed of glass in order to expose the film to two

strong mercury lamps

112 and 113 carried in a chamber 114 at the side of the tub 110. In this tub the film while exposed to the light is developed by developer therein which comprises a solution of 20 to 30 grams of sodium hydro-sulphite.

The film emerging from the tub 110 passes into a wash tub 115 containing water, which tub is constructed and equipped the same as the darkening tub 110, but omitting the glass window 111,

lights

112 and 113 and chamber 114. From this tub the film passes into a drying chamber 116 such as commonly employed in developing machines and in which the minute drops of water left from the washing in'the tub 115 are removed by any suitable drying apparatus. In order to conveniently operate the apparatus there is provided a platform 117 extending from one end of the apparatus to the other. This gives convenient access to the operating mechanism of the apparatus.

By this means I am enabled to carry out the development of motion picture films with the advantages above referred to, while avoiding any great variation in the chemicals used in the bath. At the same time the speed of the machine being constant, the time period of the development can be progressively increased by compensating for the changes in the chemical composition of the bath as by enriching of the bath by alkali bromide. Also, this end is furthered by reason of the powerful agitation accomplished by means of the pumps and agitators of the developing bath. 1 Furthermore, these purposes are aided by reason of the constant temperature which is maintained very a curately during the development.

Whi e I have described my invention above in detail I wish it to be understood that many changes may be made therein without departing from the spirit of the same.

I claim:

1. An apparatus for treating motion picture films comprising a series of tanks and motor driven means, including a controlling shaft, for regulating the distance of travel of the film through the same, comprising a shaft and a slotted guide therefor within each tank and a pulley and cable for elevating the shaft in each tank connected to the controlling shaft.

2. An apparatus for treating motion picture films comprising a tank and means for regulating the distance of travel of the film through the same, comprising a plurality of sets of guide rolls 120 and a slotted guide for one set thereof within the tank and a common linkage for simultaneously regulating the distance between the sets of rolls comprising a pulley and cable elevating mechamsm.

3. An apparatus for treating motion picture films comprising a tank, an agitator therein, means for regulating the distance of travel of the film through the same, comprising a plurality of sets of guide rolls and means for regulating the distance between the same, including a manually operable device for raising and lowering one set of guide rolls comprising a shaft and a slotted guide therefor within the tank and a pulley and cable for elevating the shaft.

4. An apparatus for treating motion picture films comprising a tank for developing the film, a reservoir through which a liquid is adapted to be circulated, means for circulating'the liquid through the tank and reservoir and a liquid 0 measuring device for continually supplying measured quantities of fresh developing liquid thereto.

5. An apparatus for treating motion picture films comprising a tank for developing the film, a reservoir through which a liquid is adapted to be circulated, means for circulating the liquid through the tank and reservoir and a thermostatic temperature control device at least partly within said tank for maintaining the temperature of the liquid therein.

6. An apparatus for treating motion picture 1,9073 I I v I. An apparatus for treating motion picture films comprising a tank for developing the film. films comprising a tank adapted to contain aa reservoir through which a liquid is adapted to liquid and means for regulating the treatment be circulated, means for circulating the liquid of the film therein by means of continually addthrough the tank and reservoir and a thermostatic temperature control device at least partly compensate for chemical changes in the liquid in within said tank for maintaining the temperature the same. oi the liquid therein, including heating and cool- 1 ISAAC ing units.

ing measured quantities 01 fresh material to iii it's