摘要:
Magnetic recording media comprise a non-magnetic base which is provided with a magnetic layer consisting of finely divided anisotropic magnetic material which is dispersible in binders and additives, the binder being a mixture of (1) a high molecular weight thermoplastic linear polyurethane, (2) a polyvinylformal binder, a phenoxy resin, a cellulose ester or a vinyl chloride copolymer and (3) an OH-containing polyurethane which is crosslinked with polyisocyanates.
摘要:
Magnetic recording media consist of a nonmagnetic base and at least one matnetizable layer which is firmly applied thereon and is based on a magnetic material finely dispersed in a binder, consisting of not less than 50% by weight of a polyurethane, and further conventional additives, wherein the magnetizable layer also contains a saturated, branched hydrocarbon.
摘要:
Magnetic recording media are produced by a method wherein a fluid dispersion of finely divided magnetically anisotropic material in a film-forming binder mixture containing a polyurethane (obtained from a polyester which possesses free hydroxyl groups, and a di- or polyisocyanate) is applied to a non-magnetic base and the magnetic layer is then hardened.
摘要:
Magnetic recording media comprise a non-magnetic base which is provided with a magnetic layer consisting of finely divided anisotropic magnetic material which is dispersible in binders and additives, the binder being a mixture of (1) an OH-containing polyurethane which is crosslinked with polyisocyanates, (2) a high molecular weight thermoplastic linear polyurethane and (3) a polyvinylformal binder, a phenoxy resin, a cellulose ester or a vinyl chloride copolymer.
摘要:
Magnetic recording media comprise a non-magnetic base which is provided with a magnetic layer which consists of a dispersion of an anisotropic magnetic material in an organic binder which consists essentially of an OH-containing polyurea-urethane binder crosslinked with polyisocyanate. The OH-containing polyurea-urethane is obtained by reacting a polydiol, a diol and a primary or secondary aminoalcohol, and if appropriate a triol, with a diisocyanate.
摘要:
Magnetic recording media comprising a non-magnetic base which is provided with a magnetic layer which consists essentially of a dispersion of an anisotropic magnetic material in a mixture of an OH-containing polyurea-urethane binder, which is crosslinked with a polyisocyanate, with a physically drying binder.
摘要:
Magnetic recording media consist of a nonmagnetic substrate and at least one magnetizable layer which is firmly applied thereon and is based on a polyurethane binder which may be crosslinked with a polyisocyanate, not less than 50% by weight of the binder consisting of a low molecular weight branched polyurethane having OH-containing urea groups at the chain ends, and the frictional properties of the binder being improved and its friction reduced by the incorporation of perfluoro groups.
摘要:
Magnetic recording media consist of a nonmagnetic substrate and at least one magnetizable layer which is firmly applied thereon and is based on a polyurethane binder, not less than 50% by weight of the binder consisting of a high molecular weight branched polyurethane elastomer having OH-containing urea groups at the chain ends, and the frictional properties of the binder being improved and its coefficient of friction reduced by incorporation of perfluoro groups.
摘要:
Magnetic recording media comprising a non-magnetic base and, applied thereto, a firmly adhering magnetic coating based on a finely divided magnetic pigment dispersed in a binder which contains at least 50 percent by weight of a special polyurethane elastomer, namely a thermoplastic polyurethane which is soluble in tetrahydrofuran, is free from isocyanate groups and has been manufactured from (A) 1 mole of a hydroxyl-containing polyester having a molecular weight of from 700 to 2,500, (B) from 0.3 to 3 moles of a linear aliphatic diol of 2 to 10 carbon atoms, (C) from 0.05 to 0.4 mole of a triol of 3 to 10 carbon atoms, and (D) from 1.35 to 4.7 moles of a diisocyanate of 6 to 30 carbon atoms, the amount of NCO groups being approximately equivalent to the amount of OH groups of the sum of components (A) to (C).
摘要:
A process for the manufacture of acicular gamma-iron(III) oxide which, because of its improved dispersibility in organic binders, is suitable for the manufacture of magnetic recording media exhibiting a particularly high orientation ratio. For this purpose, the non-magnetic acicular .alpha.-iron(III) oxide or goethite pigment is treated with from 0.5 to 10% by weight, based on the pigment, of a compound of the formula I: ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are hydrogen, alkyl of 1 to 24 carbon atoms or alkenyl of 1 to 24 carbon atoms and (RX).sup.- is selected from the group consisting of an aliphatic carboxylic acid of 1 to 18 carbon atoms, an aromatic carboxylic acid of 1 to 18 carbon atoms, a sulfonic acid and an ester of phosphoric acid and is then further processed by conventional methods to give gamma-iron(III) oxide.
摘要翻译:用于制造针状γ-氧化铁(III)的方法,其由于其在有机粘合剂中的分散性的改善而适用于制造表现出特别高取向比的磁记录介质。 为此,非磁性针状α-铁(III)氧化物或针铁矿颜料以基于颜料的0.5至10重量%的式I化合物处理:其中 R 1,R 2和R 3是氢,1至24个碳原子的烷基或1至24个碳原子的链烯基和(RX) - 选自1至18个碳原子的脂族羧酸,芳族羧酸 1至18个碳原子,磺酸和磷酸酯,然后通过常规方法进一步加工,得到γ-铁(III)氧化物。