US3050758A - Machine for striping film - Google Patents

Description

Aug. 28, 1962 l.. A. wlLKINs MACHINE FOR STRIPING FILM Filed Sept. 6, 1960 sur.

3,050,758 MACHINE FR STlNG HLM Lowell A. Wilkins, 6 N. 256th Ave., Roselle, lli. Filed Sept. 6, 1960, Ser. No. 53,983 2 Claims. (Cl. 15-109) .The present invention relates to an apparatus for applying a sound track to a motion picture film and, more specically, to apparatus for conditioning the film to receive an adherent magnetic sound track.

Magnetic sound tracks on motion picture film are becoming more commonly used in place of the conventional optical sound tracks largely because of the factors of lower cost and the ability to erase and edit a magnetic sound track. Magnetic sound on film is particularly attractive for the home movie field for these reasons.

The only area available for the incorporation of a magnetic sound track on a conventional motion picture film is the area between the marginal edge of the film and the edge of the sprocket holes. Since this area is quite limited in lateral extent, it is imperative that the magnetic material be deposited uniformly along this limited area if satisfactory recording is to be achieved.

The magnetic sound track can be applied as a paint or coating containing finely divided, magnetic iron oxide (either a gamma ferrie oxide or ferrosoferric oxide) in combination with a binder resin which may be a phenolic resin, or a thermoplastic resin such as a vinyl resin, The binder must be such that it resists the action of the developing chemicals employed in the processing of the exposed motion picture lilm.

It is particularly ditiicult to secure a magnetic sound track to color films and the like which contain an antihalation backing containing finely divided carbon particles. The presence of this backing substantially interferes with the ability of the resinous binder in the magnetic sound track to adhere to the film base, One of the principal objects of the present invention is to provide an apparatus for continuously removing a'predetermined portion of such anti-halation layer to render the film receptive to a subsequently applied magnetic sound track.

Still another object of the invention is to provide an improved cleaning roller assembly for wiping E a predetermined portion of an anti-halation layer from a motion picture film.

In its broader aspects, the present invention contemplates moving a motion picture lm at a substantially uniform rate against a periphery of a roller moving in the opposite direction, and supplying a solvent to the roller along a predetermined area thereof to thereby rub oft a predetermined area of the anti-halation layer. The apparatus embodying the invention also provides means for continuously cleaning the roller of the carbonaceous materials which are picked up during the treatment of the motion picture film.

A further description of the present invention will be made in conjunction with the attached sheet of drawings, in which: v

FIGURE 1 is a somewhat schematic View of the assembly employed in a preferred embodiment of the invention; and

FIGURE 2 is a cross-sectional View of the 'cleaning roll assembly employed in the apparatus of FIGURE 1.

As shown in the drawings:

In FIGURE 1, reference numeral indicates generally a light-tight housing in which the remaining elements of the assembly are located. Unexposed film with the emulsion side up, is fed from a supply roller 11 at a substantially uniform rate. The film 12 is put under tension by passing the lm over a sprocket 13 and then under a tension roller 14. The sprocket 13 is Vdriven in a counterclockwise direction as viewed in FIGURE 1 by any suitable drive means.

The tensioned film then is pressed against the periphery of a cleaning roller assembly by a pressure roller 15. The cleaning roller is generally indicated at numeral 16 of the drawings and is more specifically illustrated in FIGURE 2. As illustrated, the cleaning roller 16 rotates in a clockwise drection as viewed in FIGURE 1 so that the periphery of the cleaning roller 16 moves in a direction opposite to the direction of movement of the film 12 as it passes over the periphery of the roller. The cleaning roller 16 may be driven by means of a motor 17 0r ,any other suitable drive means.

After leaving the periphery of the cleaning roller 16, the film 12 passes under a second tensioning roller 18 and on to a sprocket 19 which delivers the film 12 to a takeup roller 21 where it is wound up into a reel.

Turning to FIGURE 2, it will be seen that the cleaning roller 16 consists of a hub 22 mounted on a spindle 23 including a slotted head portion 23a and a nut 25. rthe assembly of FIGURE 1 is intended to provide two striped areas along the margins of a sixteen millimeter film so that the film may be slit longitudinally in the usual manner .to produce two S-millimeter films. Accordingly, the cleaning roller 16 is-provided with two film contacting surfaces which take the form of absorptive, liquid permeable pads such as felt pads 24 and 26. A pair of end plates 27 and 28 are provided to confine the pads 24 and 26 between the plates andthe hub 22 and thereby determine the thickness of thepads 24 and 26 as they wipe against the film. A plurality of stop pins 29 extend from the hub 22 to engage the plates 27 and 28 to prvent excessive compression of the pads 24 and 26.

Returning to FIGURE 1, it will be seen that the cleaning roller 16 is partially immersed in a `tank 3,1 containing a solvent 32 which is capable of penetrating the antihalation layer on the film 12. Suitable solvents include methanol or more preferably, a combination of three parts methanol with one part acetone. Still another example of a suitable solvent is that containing ve parts methanol with one part methyl chloride.

As the cleaning roller 16 revolves, it picks up additional amounts of the solvent 32 by capillary action Within the felt pads 24 and 26. ln order to clean the felt pads continuously to remove any accumulated carbon particles therefrom, I provide a pair of spray nozzles 301V which direct a spray against the felt pads 24 and 26. In order to avoid splashing of the solvent 32, it is desirable to maintain the spray nozzles 314 below the level of the liquid in the tank 31.

A wringer roller 36 may be provided against the felt pads 24 and 26 to remove excess solvent, but still leave the pads 24 and 26 suliiciently moist to remove the predetermined areas of the film base. i

The solvent 32 may be continuously or periodically withdrawn from the tank '31 through a line 37 and the solvent then directed into a filter 38 where contaminants such as carbon particles can be removed. The clean solvent is then passed into a tank 39 where a pump 4-1 directs the clean solvent into the spray nozzles 34.

After the lm has been conditioned by the removal of the preselected areas in the manner described, the sound track may be applied by any conventional striping machine. The sound track material will normally be in a form of a lacquer containing a binder and the nely divided iron oxide particles.

From the foregoing, it will be appreciated that the apparatus embodying the present invention provides a convenient and continuous means for conditioning the surface of a motion picture film for the reception of a magnetic sound track. It should also be evident that Fatented Aug. 28, 1962 various modications can be made to the described embodiments without departing from the scope of the present invention.

I claim yas my invention:

1. Apparatus' for conditioning aY motion picture lm having an anti-halation layer for the reception of a magnetic sound track which comprises a tank containing a solvent for penetrating said anti-halation layers, a roller partially immersed in said tank, a liquid permeable pad 'carried by said roller and supplied with solvent from said tank, means for moving a motion picture film across said pad so that said pad rubs said solvent onto saidY antihalation layer along a limited portion thereof, means for rotating said roller so that its periphery moves in a direction opposite to the movement of said lm past said roller, and a spray device arranged to direct a spray of solvent at saidrpad at an area remote from the rubbing area to clean the same.

2. Apparatus for conditioning a motion picture lrn having an anti-halation layer for the reception of a magadr/5e netic sound track which comprises la tank containing a solvent for penetrating said anti-halaton layer, a roller.

partiallyV immersed in said tank, a liquid permeable pad carried by said roller and supplied with solvent from said tank, means for moving a motion picture film across said pad so that said pad rubs said solvent onto said antihalation layer along a limited portion thereof, a spray de- References Cited in the iiley of this patent UNTTED STATES PATENTS 1,352,713 Werner Sept. 14, 192()V 1,984,456 Bonamico Dec. 18,193.4V 2,305,011 Kienninger Dec. 15, 1942 2,797,170 Speed et al Junet25, 19'57

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