US2330796A

US2330796A - Cinematography

Info

Publication number: US2330796A
Application number: US423353A
Authority: US
Inventors: Charles D Bennes
Original assignee: Technicolor Motion Picture Corp
Current assignee: Technicolor Motion Picture Corp
Priority date: 1941-12-17
Filing date: 1941-12-17
Publication date: 1943-10-05
Anticipated expiration: 1960-10-05

Description

Oct. 5, 1943. c. D. BENNES 2,330,796

CINEMATOGRAPHY Filed Dec. 1'7, 1941 2 Sheets-Sheet 1 if, 2 COLOR POSITIVE 4 P MF-MONOPACK FILM COATING DRYER WASHER WASHER C 01 W W 2 Q SOUND NEQAT/l/E-SN g I v e v. i 2 o sou/v0 TRACK o l V COATER-SC l 7 i 7 EH-EMULS/ON ND NGATIVE BLUE FLASH HARDNER 0L- VELOPER 1%.; cmIv DEVELOPER B F v c D RES/DUAL MAGENTA FERR/GYAN/DE WASHER RED ASHER DEVELOPER DEVELOPER BLEACH w s R R 0 M o F a v/ 0 90000000000000.00000. 'E v E5 I I 0 I Q I O 0- O 0 0 0 w 3 y 0 w 4 w s P H WASHER YELLOW WASHER WASHER PICTURE HYPO DEVELOPER I I g'4 MISC/BIL! TY sou/v0 sou/v0 FILM WITH COLOR PICTURES SOLUTION DEVELOPER HYPO AND aLAcIr AND WHITE I I M s os H sou/v0 TRACK F o FILM DRYER c I? w 7 w COAT/N6 WASHER WASHER WASHER kEMOVER o i [1 MF 0 cl n n a a a I l- EwenZO-r': r"- T:

I I V ,Mwv M C. D. BENNES CINEMATOGRAPHY Filed Dec. 17, 1941 Oct. 5, 1943.

2 Sheets-Sheet 2 waaq a Patented Oct. 5, 1943 CINEMATOGRAPHY Charles D. Bennes, Los Angeles, Calif., assignor to Technicolor Motion Picture Corporation, Los Angeles, Calif, a corporation of Maine Application December 17, 1941, Serial No. 423,353

Claims. (0]. 95-2) In the production of motion pictures with accomp'anying sound it is often desirable to subject the sound-track and picture zones to different chemical treatments. For example in the case of color pictures the sound-track is preferably a black-and-white silver track whereas'the pictures are printed or developed in color. Independent treatment of the two zones may be accomplished by applying a protective coating over one zone while the other zone is being treated, and then removing'the coating to permit the stead of color-developingthe picture components in a single developing stage,-the picture components in the respective strata are color developed in successive stages. Inasmuch as the various methods of color development of monopack film are now well known the following general outline of a typical procedure will serve for the purpose of the present disclosure.

The monopack film illustrated in Fig. 1 comprises the usual transparent backing A and three I layers of emulsion comprising a red-sensitive first zone to be processed. However it is diificult to find a coating which will withstand the action of the wet processing and which at-the same time can be easily removed.

Objects of the present invention are to provide a method of treatment which thoroughly protects one zone while processing the other zone and which permits rapid and economical treatment of long lengths of film.

According to the present invention one of the aforesaid zones may be coated with a lacquer which is insoluble in the following processing baths, after which the other zone is: processed, the lacquer is removed with a lacquer solvent, the lacquer solvent is removed with an intermediate solvent which is miscible with the lacquer solvent and also with the subsequent processing liquid, and the other zone is then processed. The 'use of the intermediate solvent affords several important advantages. In the first place it permits the use of a hard quick-drying lacquer which is removable only with a solvent immiscible with the subsequent processing liquid, and secondly it avoids the necessity of drying the film intermediate the two processing stages in order to remove all of the lacquer solvent.

. For the purpose of illustration a typical embodiment of the invention is illustrated in the accompanying drawings in which V Fig. 1 is a cross-section of monopack film; Figs. 2,- 3 and 4 are diagrammatic views of successive sections of apparatus for processing the throughout that 'zone.

layer R, a green-sensitive layer G and a bluesensitive layer B. While the respective layers may be exposed either successivelyor -simultaneously to the different color aspects of the beam, at typical printing method comprises exposing the three layers simultaneously by printing from another color developed film or other kind of color film. Either before or after the pictures are printed the sound-track may b printed. After the sound-track has been printed the sound-track zone is covered with a coating C of lacquer or varnish which is opaque, flexible, has good adhesive quality, is impervious to moisture, fast drying and easily redissolvable. After the soundtrack zone has been coated the gelatin throughout the picture zone may be hardened. Then the picture components in the three layers are simul-- taneously developed and, if the layers have been exposed from the top, the developed records will appear in the upper strata of the respective layers. In printing from a positive film these negative records would of course be negative components.

"The first stage in the series of stages of color development consists in exposing the remainder of the light-sensitive silver salt in the lower stratum of the red-sensitive layer R. By efiecting this exposure with red light from the bottom,

only the red-sensitive layer R .is affected; and

by excluding the red light from the sound-track zone the red-sensitive layer is not affected After .the red-sensitive layer has been flashed with red light the exposed silver salts in the lower stratum of the layer R is color developed in well known manner to produce a cyan colored positive component in the layer R. The upper layer B is then flashed from the top with blue light, the light being excluded from the sound-track by the aforesaid opaque coating C, after which the exposed silver salt in the lower stratum of the B layer is color developed to produce a yellow positive picture component. At this stage no developable silver halide would remain in either of the layers B and R if the previously developing processes had the picture zone.

been found advantageous to use cyan and yellow developers which are too weak to carry the development to completion. After the cyan and yellow positive components. have been developed as aforesaid it is therefore preferable to subject the film to a suitable black-and-white developer toconvert the exposed silver halide remaining in layers B and R into silver. I

The next step consists in color developing a magenta positive component in layer G. While this may be effected by first reexposing the layer and then color developing the exposed silver halide, the magenta positive is preferably formed by adding a fogging agent to the magenta de-.

veloper in well known manner, thereby eliminating the step of reexposing the G layer.

After the three positive components have been been carried to completion. However it has from a sound-track negative SN with a similar projection printer SP. After both pictures and sound have, been printed and before the film enters the first wet stage the protective coating C is applied over the sound-track zone by means of a coater SC comprising a tank I containing the coating solution and a coating roll 2 dipping into the solution and contacting with the soundtrack margin of the film as shown in Fig. 5. The coating roll may be rotatably mounted on a shaft 3. After leaving the coater SC the film passes through a dryer CD to dry the coating, the film being twisted through 180 as indicated at 4 in passing from the coater to the dryer. After the coating is dried the film passes successively through a tank EH containing emulsion hardener, wash tank WI, a tank ND containing color developed by the aforesaid reversal method the film is firstbleached to convert all the reduced metallic silverinto a compound which is soluble in the fixingsolution that follows bleaching. The fixing solution also removes any unexposed silver halide remaining in Inasmuch as the sound-track zone is still covered by the aforesaid protective coating, the silver halide in the sound-track zone is not removed in this fixing step.

The first step consists in removing the protective covering C by dissolution in any lacquer or varnish solvent which does not affect the picture zone. Inasmuch as the sound-track zone is to be treated with aqueous solutions after the coating is removed and inasmuch as lacquer and varnish solvents are usually immiscible with water, after the coating has been dissolved off the film is first washed with some solution such as isopropyl alcohol which is miscible both with the solvent and with water, after which the alcohol is removed in a bath of water. After the sound-track zone has been thoroughly washed negative developer and thence through a second wash tank W2.

As indicated in Fig. 3 the apparatus for performing the color development step may comprise a red flasher RF for reexposing the redsensitive layer R of the film, a. tank CD containing the cyan developer, a wash tank W3, a blue fiasher BF for reexposing the layer B of the film with blue light, a tank YD containing yellow developer, a tank RD containing black-and-white developer for developing'the residual exposed silver salt not developed by the cyan and .yellow the sound-track is developed with an ordinary black-and-white developer. The unexposed and unreduced silver halide is removed from the sound-track zone with an ordinary fixing solution. Thereafter the processing is completed by washing and drying the film.

Suitable compositions for the aforesaid coating and coating remover comprise:

Coating V Per cent Nitrocellulose (30-40 second) 10 Ester gum... 5 Dibutyl phthalaten 5 Butyl acetate 23 Butyl alcohol 12 Amyl acetate 8 Ethyl alcohol 8 Toluene 27 Carbon black 2 Coating remover V Per cent Butyl acetate 30 Butyl alcohol 15 Amyl acetate 10 Ethyl alcohol 10 Toluene 35 Referring to Figs. 2, 3 and 4, which diagrammatically indicate suitable apparatus for carrying out the process, the pictures may be printed on *ie monopack film lViIF from any suitable color ")sitive CP by means of an ordinary projection printer PP; and the sound-track may be printed developers, a wash tank W4, a tank MD containing the magenta developer, a wash tank W5, a tank FB containing ferricyanide bleach, a tank PH containing hypo for fixing the picture zone and a wash tank W6. At this stage the three positive components have been developed in color, v

the silver has been removed from the picture zone and the sound-track zone still remains in its original condition because of the protective coating.

As described and claimed in the copending application of John R. Clark, Jr., Serial No. 423,354, filed on even date herewith, the red flasher RF preferably comprises a tank 6 containing water in which the film is submerged while flashed, thereby to prevent the sound-track zone from being fogged by stray light resulting from reflection at surfaces of the film and emulsion layers. The bottom of the tank 6 is provided with a window I through which the red light is projected by an optical systemsimilar to that used in a projection printer.

Referring, to Fig. 4, which diagrammatically illustrates apparatus suitable for processing the sound-track zone, the protective coating C may a wash tank W8, fixing tank FI-I, wash tank W9 and thence through a drier FD.

'As shown in Figs. 6 and 7 the film MF is led into the tank CR over a roller 8 and thence loops between successive lower and upper rolls 9 and m within the tank. Adjacent the outside of each loop of film the brushes 5 are mounted on a shaft l I journaled in a frame l2, the shaft being rotated by a motor l3 through the medium of a belt 14 and pulleys l5 and IS. The rate of rotation may be of the order of 500 B. P. M. As indicated by the arrow H in Fig. 6 the brushes are preferably rotated in the direction opposite to the direction of film travel. While various kinds of soft brushes may be used to wash off the coating without damaging the underlying emulsion, the brushes are preferably formed of felt. Opposite the brushes 5 rollers l8 are rotatably mounted on a rod iii to hold the film against the brushes.

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents which fall within the scope of the appended claims.

I claim:

1. In the art of processing cinematographic film the method of forming a sound record and a picture record in sound and picture zones respectively which comprises coating one zone with lacquer, processing the other zone with a solution in which the lacquer'coating is insoluble, removing the coating with a lacquer solvent, processing the first zone with a liquid immiscible with said solvent, and intermediate said last two steps removing said solvent with a solvent miscible with said solvent and also with said liquid.

2. In the art of processing cinematographic film the method of forming a sound record and a picture record in sound and picture zones respectively which comprises coating one zone with a water-insoluble lacquer, processing the other zone with an aqueous solution, removing said coating with a lacquer solvent, which is immiscible with water, removing said solvent with an intermediate solvent which is miscible with said solvent and also with water, and then processing the first zone with an aqueous bath.

3. In the art of processing cinematographic film the method of forming a sound record and a picture record in sound and picture zones respectively, which comprises selectively exposing one zone to light to form a latent record and then developing the latent record, prior to said exposure and development coating the other zone with a lacquer which is insoluble in the developer so that the coating protects against chemical action, after said exposure and development removing said coating with a solvent which is immiscible with water, removing said solvent with is miscible with an intermediate solution which said solvent and also with water, and then processing said other zone in an aqueous bath.

4. In the art of processing cinematographic film of the type having superposed emulsion strata the method of producing color pictures and a sound track more opaque than the pictures, which comprises forming in said strata respectively latent records of several color aspects of a scene, developing said latent records, reexposing the strata to form reversed records, color developing the reversed records in colors appropriate to said aspects respectively, prior to said reeXposure and color development coating the sound track zone with a, protective covering which is insoluble in the color redeveloper so that the covering protects the sound track zone against the chemical action of the color redeveloper, after said color development removing said coating with a solvent which is immiscible with water, processing the sound track zone in an aqueous bath, and intermediate said last two steps removing the solvent with an' intermediate solvent which is miscible with the lacquer solvent and also with said aqueous bath.

5. The method of producing color pictures and a relatively opaque sound track in cinematographic film having a plurality of superposed emulsion strata, which comprises forming in said strata respectively latent records of difierent color aspects of a scene and forming in a plurality of said strata a latent sound track, developing said latent records, reexposing the strata to form reversed records, color developing the reversed records in colors appropriate to said aspects respectively, prior to said reexposure and color development coating the sound track zone with a protective covering which is insoluble in i the color redeveloper so that the covering protects the sound track zone against the chemical action of the color redeveloper, removing said coating with a solvent which is immiscible with water, processing the sound track zone in an aqueous bath, and intermediate said last two steps removing the solvent with an intermediate solvent which is miscible with the solvent and also with said aqueous bath.

C D. BENNES.