US1413984A - Talking-machine record and process of making same - Google Patents

Description

specification.

LACHINE; QUEBEC, CANADA. Y

TALKING-MACHINE RECORD AND 1,413,984. No Drawing.

To'all whom it may concern:

Be it known that I, EDWARD R.v H RRrs, a subject of the King of Great Britain, and resident of borough of Manhattan, in the city -of New York, in the county f York and State of New York, have invented certain new and useful Improvements in Talking-Machine Recordsand Processes of Making Same, of; which the following is a The object of my invention is thevmanufacture ,of a talking machine record, the body of which will be non-thermoplastic, but forming under heat and pressure a solid material which is not liable to warp and is of suflicient strength and hardness to meet all r uirements,

In t e present invention the objectionable features commonto records made of paper or other material filledwith a thermoplastic binder are overcome. In records of this class the tendency 'for the heat and pressure used in forming the record is to force out the thermoplastic filling and leave the paper or fibrous material with insufiicient, binding material to cause.it to adhere and form' a solid ss.. This adhesion is absolutely necessary o prevent the paper from'returning when pressure is' released and causing the record to warp, orotherwise distort the configurations thereon. Thus in using the ord1-. nary non-thermoplastic material suchas.

I glue or sodium silicate withthe usual facingof phonographstock, I have found that the tendency is for the pressure to crush the' R filling material, causing it. to break up and produce an unmarketable record.

My inventioncons1sts in the manufacture of a talking machine record consisting of paper, cardboard or other fibrous material .and permeating it with a non-thermoplastic material-consistsing of a' mixture of glue,

plastic gums,

dextrine and shellac.

In the manufacture of such a record I make an aqueous solution of each of the above ingredients and combine it with' the paper or mixing it with the pulp or fibre and subsequently forming it into disks or sheets, or lgsplacing sheets or (liSkSnof the paper or re into a bath consisting of the, glue, dextrine and shellac. Other, non-thermoglues or binders can be em-- j ploy ed to give the characteristics desired to I the ecord. rdi-nary 5 purpose and dissolvedy heating it-i1i an New other material by shellac'fma be used for this-- IROCESS OI MAKING SAME.

Specification oiLetters Patent. Patented Apr, 25, 1922, Application filedOctober a1, 1919. Serial no. eaassa.

alkaline solution such as'borax and water n. Y., assronon- T0 JOHN may gamers, or

in the proportion of about. 1 oz. of'borax to 12 ozs. of water: and about 41? ozs. of shellacn This forms a brown solution when borax.

is used, dark red with other alkalies. Borax has been found less inclined'to thicken theis subsequently added but any. alkali canbe used and be within the scope glue which of this invention. A solution of glue is now prepared by adding about 6 ozs. of glue to 12 ozs. of water, in which has been dissolved about 4 dr. 0f borax. I prefer what is known as-fish glue for the reaspn that it (is less inclined to become thick and syrupyv when the shellacsolution is added.

other glues are used this tendency maybe overcome by adding a few drops of a weak solution of acetic acid to the shellac'solution before mixing with glue. I mix. these Y two solutions stirring while doing so and the resultant 1s a brown liquid which should be thin and free from all traces of coagulation.

I now take dextrine 1O ozs.-and dissolve in I water 20 ozs. to which has been "added i oz.

of -borax and 1 oz. ofsugarr This will dissolve more quickly if heated but it must not be boiled or heated above about 150 F When all the dextrine is dissolved Iv add this to the previously described shellac and glue'mixture while stirring semen The re-' and should soak through a piece of dry blotting paper floated uponthe surface in about 15 seconds. If necessary to further thin the. li 'uidadd water to' which borax has been a ded about l dram to 8 ozs. of water. The above compound is particularly adapted for a dipping or impregnating bath and is used by placing therein or other fibrous material and allowing themto remain until thoroughly soaked. When I make the phonograph record from fibre or pulp which has not been \made into such as wood'flour, ground fibre, asbestos fibre, orother fibrous materials, I mix the shellac glue dextrine compound directly sheets or discs of paper sheets,

with the, fibre and form a thick paste or sultant mixture should be thin and liquid 5 I in hardness and texture and this result is more satisfactorily accomplished if heat is applied during the operation of pressing. When a small amount of moisture is present due to the water not being all evaporated or the material being in a moist place, the

compound becomes somewhat soft or plastic,

when heated, this property disappearing when thoroughly dried. I now coat the material with ordinaryrecord stock reduced to a powder and apply 'sufiicient heat to cause the powder to adhere, after which it is laced between heated dies and pressed as In the ordinary method of pressing records or in the case of a cheap record the sound grooves may bepressed'directly into the material without the above facing ofstock the sponginess of the material permitting a fair pressing to be made. While the above proportions are a fair avera it is essential to the success of my inventlon that I am not limited to any special proportions of the mixture ingredients for the following good reasons: Talking machine records are made by pressing the record material between polished metal dies which contain the sound ooves in relief. The material is usually gated until soft and cooled while. under pressure. Unless sufiicient resistance is offered to the action of the press the material is not broughtinto absolute contact with the polished surface of the die and animperect record results. Also if the material'is too hard to accommodate the slight unevenness always present in the dies or material a similar result is attained. One great value of my invention lies inthe fact that this property of hardness or softness can 'be easily controlled. Thus by adding more dextrine an additional hardness or firmness is obtained, a tendency to break or become dry and unmanageable is overcome by addlng more glue and an increase in the amount of shellac causes a softness and also prevents the material from being affected by andinaccuracies, present it moisture. As all record pressing establishments differ in the amount of heat, pressure,

is an easy matter to definitely find the proportions best suited to the needs of any establishment and make the material accordingly. It is also necessary that I be not limited to any roportions so that ll'may use different kinds of paper or fibrous-material and use the release mixture which. works best with the one ll wish to useor can procure. Another-prop erty ofimy inventionwhich is very valuable is that the material dries with a "porous structure as opposed to the closing of the pores or voids which is the result of using a gum or resins lit is necessary that the air displaced by thecompression beallowed to escape otherwise blisters result and the recdoes not concentrate at the surface and edges as is the case with gums, resins, or sizes. a

This property also assists in preventingtherecord from Warping. ll. claim also that l may use the ingredients above mentioned separately if necessity arises. ll find that sometimes when using a fibrous material such as sulphite pulp, or cheap grades ,of paper in which either acid or alkali is present the efiect of repeated immersions is to cause the liquid to become thick or even to preci itate one of the ingredients and render t e bath unfit for further use. I claim the right therefore to use separate solutions and be within the'spirit of my invention.

Having described my invention what I claim is:

1. A process of manufacturing talking machine records which consists in combining ingredients of paper pulp or similar fibrous material with glue, dextrine and shellac and pressing the resultant non-thermoplastic material into record forrnl 2. A process of manufacturing talking machine records whichconsists in permeating a disk of'paper" or similar material with a mixture of glue, dextrine and shellac and coacting the disk on one or both surfaces with a facing of phonograph stock and pressing the resultant. non-thermoplastic mass into record form.

3. A talking machine record consisting of paper or similar materials combined with glue, dextrine and shellac.

4. A talking machine record consisting of paper or similar materials permeated by a non-thermoplastic mixture of glue, dextrineand shellac and coated on one or both sur faces with a facing of phonograph stock.

Signed at New York city, in the county of New York and State of New York,'this 30th day of October, A. ll: 1919.

, EDWARD R. HARRIS.