Patent GB-464527-A (GB)
Title: Improvements in or relating to the production of sound records
IPC: G11B3/70
Filed: 1936-02-20
Abstract: A process for producing sound records consists in mechanically recording in the usual manner upon a layer consisting of a mixture of gelatine, or other colloid capable of being tanned, with one or more organic compounds which under the action of light exert a tanning action on the colloid, the record being fixed after the groove has been made, by engraving or the like, by exposure of the material to light.  A large number of substances which may be used in carrying out the process are specified.  As suitable colloids, albuminous substances such as casein, collodion, asphalt, and artificial resins such as vinyl resins are mentioned.  Materials such as graphite or metal dust may be incorporated therewith, or there may be an admixture of waxes, together with a suitable solvent.  Among light-sensitive organic compounds that may be used, the following are specified: higher molecular diazo-compounds, particularly such as contain three carbo-cylic rings; carbonyl compounds, particularly quinones, and preferably their sulphonic acids; dyestuffs, particularly xanthone and other acid dyestuffs; aromatic nitro-compounds, such as nitro-derivatives of the benzene and naphthalene series, particularly such compounds of nitro-naphthalene as are substituted by oxyalkyl or acid groups.  A number of examples of methods of carrying out the process specifying numerous alternative mixtures and methods of preparation, are given.ALSO:A process for producing sound records consists in mechanically recording in the usual manner upon a layer consisting of a mixture of gelatine or other colloid capable of being tanned with one or more organic compounds which under the action of light exert a tanning action on the colloid, the record being fixed after the groove has been made by engraving or the like, by exposure of the material to light.  A large number of substances which may be used in carrying out the process are specified.  As suitable colloids, albuminous substances such as casein, collodion, asphalt, and artificial resins such as vinyl resins are mentioned.  Materials such as graphite or metal dust may be incorporated therewith, or there may be an admixture of waxes, together with a suitable solvent.  Among light-sensitive organic compounds that may be used the following are specified: higher molecular diazo-compounds, particularly such as contain three carbocylic rings: carbonyl compounds, particularly quinones, and preferably their sulphonic acids: dye-stuffs, particularly xanthone and other acid dye-stuffs: aromatic nitro-compounds, such as nitro-derivatives of the benzene and naphthalene series, particularly such compounds of nitro-naphthalene as are substituted by oxyalkyl or acid groups.  A number of examples of methods of carrying out the process specifying numerous alternative mixtures and methods of preparation, are given.ALSO:A process for producing sound records consists in mechanically recording in the usual manner upon a layer consisting of a mixture of gelatine, or other colloid capable of being tanned, with one or more organic compounds which under the action of light exert a tanning action on the colloid, the record being fixed after the groove has been made, by engraving or the like, by exposure of the material to light.  A large number of substances which may be used in carrying out the process are specified.  As suitable colloids, albuminous substances such as casein, collodion, asphalt, and artificial resins such as vinyl resins are mentioned.  Materials such as graphite or metal dust may be incorporated therewith, or there may be an admixture of waxes, together with a suitable solvent.  Among light-sensitive organic compounds that may be used the following are specified: higher molecular diazo-compounds, particularly such as contain three carbo-cyclic rings; carbonyl compounds, particularly quinones, and preferably their sulphonic acids; dye - stuffs, particularly xanthone and other acid dye-stuffs; and aromatic nitro-compounds, such as nitro-derivatives of the benzene and naphthalene series, particularly such compounds of nitro-naphthalene as are substituted by oxyalkyl or acid groups.  A number of examples of methods of carrying out the process, specifying numerous alternative mixtures and methods of preparation, are given.