Abstract The invention relates to a magnetic recording medium, for example a magnetic tape, which comprises a carrier and a magnetizable coating provided thereon which comprises a binder as well as a magnetic pigment dispersed in the binder by means of a dispersing agent. As a dispersing agent is used an N-acylsarcosine derivative. Herewith an optimum dispersion of the pigment in the binder is obtained in a short dispersion time. An excess of dispersing agent serves as a lubricant upon migration. The acyl group comprises preferably an aliphatic or olefinic hydrocarbon chain having 12-22 carbon atoms. Furthermore are to be preferred salts of N-acrylsarcosine, in particular metal salts, alkali metal salts, alkaline earth metal salts and amine salts.
A magnetic recording medium comprising a non-magnetic carrier and a magnetizable coating provided on said carrier, said magnetizable coating comprising a binder and magnetic pigments finely dispersed therein by means of a dispersing agent, said dispersing agent being an N-acylsarcosine derivative.
Claim 2
Dependent Claim
41 words
A magnetic recording medium comprising a non-magnetic carrier and a magnetizable coating provided on said carrier, said magnetizable coating comprising a binder and magnetic pigments finely dispersed therein by means of a dispersing agent, said dispersing agent being an N-acylsarcosine derivative.
Claim 3
Dependent Claim
32 words
The magnetic recording medium of claim 1, wherein the dispersing agent corresponds to the formula ##STR2## or salts thereof, wherein R is an aliphatic or olefinic hydrocarbon chain of 12-22 carbon atoms.
Claim 4
Dependent Claim
40 words
The magnetic recording medium of claim 2 wherein the dispersing agent is a alkali metal salt, an alkaline earth metal salt, a zinc salt, a copper salt, a lead salt or an amine salt of the N-acylsarcosine of claim 2.
Claim 5
Dependent Claim
21 words
The magnetic recording medium of claim 3 wherein the dispersing agent is a sodium salt of the N-acylsarcosine of claim 2.
Claim 6
Dependent Claim
33 words
The magnetic recording medium of claim 3 wherein the dispersing agent is an aliphatic or olefinic amine salt of the N-acylsarcosine wherein the amine moiety contains a hydrocarbon chain of 12-22 carbon atoms.
Claim 7
Dependent Claim
18 words
The magnetic recording medium of claim 3 wherein the dispersing agent is a triethanolamine salt of the N-acylsarcosine.
Claim 8
Dependent Claim
16 words
The magnetic recording medium of claim 1 wherein an excess of the dispersing agent is present.