US2053396A

US2053396A - Reproduction of sound

Info

Publication number: US2053396A
Application number: US716006A
Authority: US
Inventors: Eggert John; Schmidt Richard
Original assignee: IG Farbenindustrie AG
Current assignee: IG Farbenindustrie AG
Priority date: 1930-05-08
Filing date: 1934-03-16
Publication date: 1936-09-08
Anticipated expiration: 1953-09-08

Description

Patented Sept. 8, 1936. 2,053,396

A UNITED STATES PATENT OFFICE REPRODUCTION OF SOUND John Eggert. Leipzig-Goldie, and Richard Schmidt, Dessau, Germany, asslgnors to I. G. Farbenindustrle Aktiengesellschaft, Frankfort-on-the-Main, Germany No Drawing. Application March is, 1934, Serial No. 716,006. In Germany May 8.

4 Claims. (Cl. 274-46) Our present invention relates to a process for gate is preferably led to a device by which the the reproduction of sound. wetting liquid is stripped oil and the film is dried.

One of its objects is an improved process for What we claim is: the reproduction of sound. Further objects will 1. In the process of reproducing sound from 6 be seen from the detailed specification following a photographic sound record the steps which hereafter. comprise coating the film having an emulsion According to this invention we have found that layer and a support and being scratched, at most, the undesired ground noise in the reproduction in a minor degree in the breadth of the sound of photographic sound records is considerably record .on at least one side with a liquid being 10 reduced by coating the film with a thin layer of uninflammable at the temperature prevailing in 10 a liquid which is uninfiammable at the temperathe gate of the reproducing apparatus and havture prevailing in the gate of the reproducing ing -a refractive index approximately equal to apparatus and having a retracting index which is that of the support prior to reproduction, reapproximately the same as that of the support. producing the sound while the liquid is applied The effect of the invention will be appreciated to the film, and removing the liquid from the when considering that this holds true already for film after reproduction.

the reproduction of sound records which are 2. In the process of reproducing sound from a played for the first time and is increased with photographic sound record the steps which comthe number of performances inasmuch as it comprise coating the film having an emulsion layer 'pensates also for the scratching of the sound and a support and being scratched, at most, in a 0 track caused by the use of the film. The appllminor degree in the breadth of the sound record cation of the invention is particularly useful in on both sides with a liquid being uninfiammable the case of photographic sound records regisat the temperature prevailing in the gate of the tered on lenticular film. With these films the reproducing apparatus and having a refractive lenticular elements cause considerable ground index approximately equal to that of the support noise, even in case of the lenticular elements beprior to reproduction, reproducing the sound ing eliminated by one of the known processes while the liquid is applied to the film, and rebecause the planing processes do not work as ac-' moving the liquid from the film after reproduccurately as it is desirable. The lenticular eletion.

ments may be any of the known kind such as 3. In the process of reproducing sound from a 30 rounded studs or picots, or cylinder lenses exphotographic sound record recorded on lenticular tending in longitudinal or transverse direction film having an emulsion layer and a support and .of the film. being scratched, at most, in a. minor degree the The films may be wetted on one side only or on steps which comprise coating the film in the both sides in the breadth of the sound record. breadth of the sound record onboth sides with It is, however, preferable to coatthem on both a liquid being uninflammable at the temperature sides with a thin layer of liquid. The coating of prevailing in the gate of the reproducing appaliquid may be applied by pad continuously wetted ratus and having a refractive index approximatewith the liquid, or it may be applied by a coatly equal to that of the support prior to reproing roller, or a suitable nozzle or in any other duction, reproducing the sound while the liquid 40 suitable manner. The liqu ds e pr f a ly is applied to the film, and removing the liquid easily volatile so that they can be removed by from th film after reproduction,

evaporation. Sui ab e liquids for instance, 4. In the process of reproducing sound from a.

halogenated hydrocarbons such as carbon tetraphotographic s und record the steps which comchl id or there may be used animal an s prise coating the film which is scratched at most table oils which have no n ncy to rm resin a. minor degree in the breadth of the sound us products which would soil the apparatus record on aal ast one side with carbon tetra- If the liquidis nonvolatile it may be removed chloride prior to reproduction, reproducing the by an e y volatile solvent which can e ssound while, the carbon tetrachloride is applied tilled off f r r ve t coating q idto thefilm', and removing the carbon tetrachlo- The wetting of the film m y b effected prior ride from the film after reproduction.

to its introduction in the projector or also while i n the projector, for instance, while passing JOHN EGGERT.

through the gate. The film, after leaving the RICHARD SCHMIDT. til!