Patent GB-418096-A (GB)
Title: Improvements in the manufacture and production of masses containing metals in a state of fine dispersion
IPC: G11B5/706
Filed: 1934-01-20
Abstract: Masses containing metals in a highly dispersed form suitable for the manufacture of sound records are produced by vigorously working a metal powder capable of being magnetized, and obtained by the thermal decomposition of the corresponding metal carbonyl, with a film forming highly viscous substance until most of the agglomerated particles contained in the initial metal powder are broken down. Suitable film forming substances are cellulose derivatives such as cellulose hydrate, esters or ethers; polymerization products such as polyvinyl and polyacrylic compounds; condensation products such as the polyhydric alcohol polybasic acid type, e.g. glycerol and phthalic acid; also natural and artificial rubber.  The metal employed is preferably iron, but may be alloys obtained from mixtures of iron carbonyl with nickel, cobalt, chromium, tungsten or molybdenum carbonyls.  Alloys of non-ferrous metals capable of being magnetized may likewise be used.  The metal powder is incorporated in the viscous mass by vigorous stirring, or preferably by passing through rollers.  In an example, plastic acetyl cellulose is kneaded on friction rollers with 200 parts of iron powder obtained from the carbonyl, until in a thin film of the mass no, or only a few, iron particles are greater than 6 to 8 m .ALSO:Masses containing metals in a highly dispersed form suitable for the manufacture of sound records are produced by vigorously working a metal powder capable of being magnetized, and obtained by the thermal decomposition of the corresponding metal carbonyl, with a film forming highly viscous substance until most of the agglomerated particles contained in the initial metal powder are broken down.  Suitable film forming substances are cellulose derivatives such as cellulose hydrate, esters or ethers; polymerization products such as polyvinyl and polyacrylic compounds; condensation products such as the polyhydric alcohol polybasic acid type, e.g. glycerol and phthalic acid; also natural and artificial rubber.  The metal employed is preferably iron, but may be alloys obtained from mixtures of iron carbonyl with nickel, cobalt, chromium, tungsten or molybdenum carbonyls.  Alloys of non-ferrous metals capable of being magnetized may likewise be used.  The metal powder is incorporated in the viscous mass by vigorous stirring, or preferably by passing through rollers.  In an example, plastic acetyl cellulose is kneaded on friction rollers with 200 parts of iron powder obtained from the carbonyl, until in a thin film of the mass no, or only a few, iron particles are greater than 6 to 8 m .ALSO:Masses containing metals in a highly dispersed form suitable for the manufacture of sound records are produced by vigorously working a metal powder capable of being magnetized, and obtained by the thermal decomposition of the corresponding metal carbonyl, with a film forming highly viscous substance until most of the agglomerated particles contained in the initial metal powder are broken down.  Suitable film forming substances are cellulose derivatives such as cellulose hydrate, esters or ethers; polymerization products such as polyvinyl and polyacrylic compounds; condensation products such as the polyhydric alcohol polybasic acid type, e.g. glycerol and phthalic acid; also natural and artificial rubber.  The metal employed is preferably iron, but may be alloys obtained from mixtures of iron carbonyl with nickel, cobalt, chromium, tungsten or molybdenum carbonyls.  Alloys of non-ferrous metals capable of being magnetized may likewise be used.  The metal powder is incorporated in the viscous mass by vigorous stirring, or preferably by passing through rollers.  In an example, plastic acetyl cellulose is kneaded on friction rollers with 200 parts of iron powder obtained from the carbonyl, until in a thin film of the mass no, or only a few, iron particles are greater than 6 to 8 m .