US2029102A - Gramophone record and process for manufacture thereof - Google Patents

Description

Patented Jan. 28, 1936 UNiTED STATES PATENT OFFICE GRAMQPHONE RECORD AND PROCESS FOR MANUFACTURE THEREOF ration No Drawing. Application August 7, 1930, Serial Ne. 473,787. In Great Britain May 16, 1930 7 Claims.

This invention relates to gramophone records of the type in which two discs of celluloid or like material have positioned between them a printed sheet of paper or similar material which is visible through :the discs.

Such recordshave previously been made either by inserting the sheet of paper between the discs and subjecting them .to heat and pressure .under matrices in the usual way, said heat and pressure causing the outer edges of the discs and also the inner edges around the central hole to come into contact with their fellow edges and adhere together, or by making the celluloid discs of substantially greater diameter than the paper so that both the discs extend beyond the edge of the sheet or paper before the record is made, the central opening in the sheet of paper being also of substantially greater :diameter than the openings in 'thesc'elluloid discs with the result that distinct zones of the discs lie opposite each other around the edge of the sheet and also around the central hole.

In the former arrangement, the sheet of paper is provided with small perforations and adhesion is obtained by the use of a cement penetrating the said perforations thus making contact between the celluloid discs. In this latter arrangement the records have been heated to ZOO-220 F. under a pressure of 1800 to 2200 lbs. per square inch.

Dificulty has been experienced with such arrangements in obtaining perfect adhesion between the celluloid discs and the interposed sheet of paper; moreover, such records are found to warp quickly.

The object of this invention is to overcome these disadvantages and to obtain a gramophone record of the above mentioned type wherein no cement or adhesive is used to obtain the necessary adhesion between the celluloid discs and paper and also a record which is cheap to manufacture and which may be of pleasing appearance.

A gramophone record according to the present invention comprises two sheets of celluloid or like material between which is interposed a sheet of material adapted to receive print and which is co-extensive with the discs so as to prevent any contact between the celluloid discs.

The process for manufacturing such a gramophone record consists in primarily heating a hydraulic press to approximately 250 F. At about this temperature a disc of celluloid or like material is placed on each matrix in the press and on either matrix over the disc is placed a sheet of material such as paper which has receivedrany desired print. The press is then closed for a period of 30-40 seconds at the same temperature and pressure applied to approximately 60 tons. press .cooledlto about .70 fora period between 20 to 30 seconds. Cooling to about 70 F. produces a perfect adhesion between the discs of celluloid and intervening sheet of paper.

In order to allow the record thus formed to separate from the matrices, the press is now reheated without pressure until adhesion between the record and the matrices is broken down.

The press in the first instance should not be allowed to cool to a temperature lower than 60 F. since itis found that the celluloid discs tend at a temperature below 60 F. to adhere to the Stampers, so that on separation thereof the sheet of paper splits into two portions each of which adheres to one celluloid disc, the record thus being destroyed.

It will be observed that according to this invention it is unnecessary to use any cement in obtaining the adhesion between the discs and intervening sheet of material.

The central hole in the sheet of paper is preferably of smaller diameter than those in the discs and in some cases it may be advantageous to provide a sheet of paper which is of greater diameter but in no case less than the discs between which it is placed, the excess paper being removed either during or after the stamping process.

Owing to the fact that the celluloid discs do not in any way contact with one another, perfoot adhesion between the discs and sheet of paper is obtained. The sheet of paper may receive print on one or both sides so as to impart to the finished record a pleasing effect; or of course, advertisements, photographs, etchings, etc., may be displayed on the sheet of paper.

The matrices of the press employed to unite the layers of the record preferably carry also the sound record for forming the groove in the outer faces of the celluloid, but the record blank may, if desired, be made initially and the sound record thereafter pressed therein by a second operation. It will be understood that the appended claims are generic to both record and r cord blank.

The expression thin flexible celluloid disks is used in the appended claims to designate celluloid disks of a composition and limited thickness such that the finished record made up of Then the pressure is taken off and the g two such disks with an intermediate paper disk may be folded up as a sheet of music or a newspaper without cracking or otherwise injuring the record.

What I claim is: 1.The method of forming a gramophone record without the use of an adhesive, cgnsisting in placing superposed thin, flexible transparent discs of celluloid together with an intermediate 7 co-extensive sheet of fibrous material in a heated press, then pressing the discs and sheet together while the press remains heated sufficiently to cause the surfaces of the celluloid disks in contact with the paper to be extruded into the pores of the paper and thus eifectia permanent union of the paper and celluloid disks, and then cooling the press and removing the pressure.

2. The method of forming'ja gramophone record' without the use of an adhesive, consisting in placing superposed thin, flexible, transparent discs of celluloid together with an intermediate co-extensive sheet of fibrous material between matrices of a heated press; then pressing the matrices against the discs and sheet while the press remains heated sufficiently to cause the surfaces of the'celluloid disk in contact with the paper to be extruded into the pores of the paper and thus effect a permanent union of the paper and celluloid discs, then cooling the press and renf ioving the pressure, and finally reheating the press to break down the adhesion betweerf the record blankand the matrices. 7

3. The method. of forming a gramophone 'rec- 0rd without the use of an adhesive, consisting in placing the superposed thin flexible transparent discs of;;celluloid together with an intermediate co-extensive sheet of fibrous material in a press heated between 250 F. and 280 F,, then pressing the discs and sheet while the press remains heated, and then cooling the press to besure to effect the'complete union of the:discs and sheet; e

A gramophone record comprising a pair of thin, flexible, celluloid disks having sound grooves therein and a sheet of paper bearing on its surface printed or pictorial matter interposed between said disks and united thereto by direct adhesion of the paper to the celluloid extending through the interposed layer of inls' forming said printed or pictorial matter.

5. A gramophone record; comprising a pair of thin, flexible, celluloid disks having sound grooves therein and a sheet of paper bearing on its surface printed or pictorial matter interposed between said disks and united thereto by direct adhesion ofthe paper to the celluloid extending through the interposed layer of ink forming said printed or pictorial matter, said record being substantially symmetrical with respect to its median piane whereby warping of the record is prevented. V

6. A gramophone record comprising a pair of thin, flexible, celluloid disks having sound grooves V therein and a sheet of paper interposed between i said disks: and united thereto by direct adhesion of the paper to the celluloid, said record being siibstantially symmetrical with respectgto its median planewhereby warping of the record is prevented.

1'7. A gramophone record comprising a pair of substantially identical, thin, flexible celluloid disks having sound grooves therein and a sheet of paper bearing on its surface printed or pictorial matter interposed between said disks and united thereto by direct adhesionzof the paper to the celluloid extending throughgthe interposed layer of ink forming said printed or pictorial matter, said disks being of substantially uniform cross-section throughout whereby said record is substantially symmetrical with respect to 40 its median plane. GUY HILI-IOUSE.