US1456047A - Record for gramophones and the like - Google Patents

Description

Patented 22, 1923.

PAUL BALKE AND GUSTAV LEYSIEFFER, OF TBOISDOBF, GERMANY.

RECORD FOR GRAMQPI-IONES AND THE LIKE.

No Drawing.

T 0 all whom it may concern:

Be it known that we, PAUn BALKE and GUs'rAv LEYSIEFFER, residing at Troisdorf, Germany, have invented an Improvement in. Records for Gramophones and the like, f. which the following is a specification, and for which application forlietters Patent has been made in the following countries on the dates set forth: Cermany, Oct. 19, 1920; Denmark, Aug. 1, 1921; England, Sept. 23, 1921; Finland, Aug. 9, 1921; France, Aug. 10, 1921; Holland, Aug. 1, 1921; Italy, Aug. 3, 1921; Japan, Sept. 10, 1921; Luxemburg, Aug. 3, 1921; Norway, Aug. 12, 1921; Austria, Aug. 1, 1921 Poland, Aug. 4, 1921; Portugal, Sept. 3, 1921; Houmania, Aug. 20, 1921; Sweden, Aug. 8, 1921; Switzerland, Aug. 3, 1921; Spain, Aug. 25, 1921; Hungary, Aug. 1, 1921; Belgium, Sept. 23, 1921; Bohemia, Sept. 22, 1921.

The purpose of the invention is to provide a phonograph record of superior quality and durability which will nevertheless be very cheap in cost. In our British Patent No. 169,232 based on application 16,281 of 1920, we have described a material suitable for making a phonograph record and consisting of a homogeneous mass of cellulose derivative such as cellulose esters or cellulose ethers as, "for example, ethylcellulose, a greater quantity of a finely ground filling material, for example, cork or fibrous substances such as cellulose, cotton, peat and the like, and a. gelatinizing agent such as methyl or ethly-urea utilized in excess. that is, in a. larger proportion than is required tire. As set forth in said patentthe tollowing ingredients are preferred 25 kg. nitro-cellulose, 42 cellulose. 5 kg). any suitabl black pigment tor coloring the records, 18 kg. gelatinizing agent, such as methyl or ethyl-urea In accordance with our present invention we provide a body or core for the record consisting of a base of cheap material such as resins to which are added mineral or fibrous substances, thin metal sheets, prepared or unprepared cardboards, thin wood or similar substances. On this body there is formed a superficial coating consisting of a thin layer of the material or composition above set forth and which receives-the sound reproducing grooves of the completed record.

for gelatinizing the cellulose deriva Application filed November 18, 1921. Serial No. 516,224.

This material may be made of exceeding thinness, for example, .3 of a millimeter, a. thinness which would be impracticable in the case of shellacked material hitherto employed.

The coating material may be produced in very thin sheets and used for covering the body of base material or it may be ground to a fine powder which may be sprayed on the body and then compressed thereon to form a single plate.

As the composition described in itself cheaper than the shellac compositions hitherto commonly used for records its employment in connection with a still cheaper body or core makes an exceedingly cheap record. At the same time this relatively cheap coating material may be made still thinner than would be practicable in the case of shellac. This not only gives cheapness but provide a record superior to one made of shellac because of the elasticity and flexibility of the material. The shellac material hitherto employed is brittle and in a thin layer would be likely to crack under relatively small shocks and strains and in a thin layer would not form a groove accurately reproducing sound whereas the elastic material employed is not brittle but highly durable and will give accurate sound reproduction.

Having now particularly described and ascertained the nature or" our said invention and in what manner the same is to be performed, we declare that what we claim is c-- 1. A gramophone record comprising a body of base material. having a superficial coating receiving the sound groove and com- .)rising a vehicle of gelatinized cellulose derivative and a fibrous tiller.

2. A gramophone record comprising a body of base material having: a superficial coating receiving the sound groove and consisting of a compound comprising cellulose ester, a greater mass oi finely ground filler and an excess of gelatinizing agent.

In testimony whereof we afiix our signatures inpresence of two witnesses.

DR. PAUL BALKE. DR. LEYSIEFFER.

VVitnesses- ANTON NORM, J osnr STEINBERGER.