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Thin film magnetic head with a magnetic gap spacer of a thermally decomposed polymer

Assignee: NEC Corp
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Filing: 1987-03-18
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Granted: 1988-06-07
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Expires: 2007-03-18
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Abstract

Abstract A thin film magnetic head comprises a magnetic gap spacer layer interposed between two soft magnetic members at least one of which is formed in a thin film form. The magnetic gap spacer layer is made of a thermally decomposed polymer of a metallic compound represented by the formula, M(OR1)m(R2)n-m, where M is a metallic element selected from metals and metalloids which are elements intermediate in properties between the typical metals and non-metals, R1 being one selected from hydrogen and an alkyle group, R2 being an alkyle group, n being a valence of the metallic element, and m being an integer equal to or less than n. Typical ones of the metallic compound are tetraisopropyl titanate, tetranormalbutyl titanate, tetraalkoxysilane, organosilanol, and aluminum isopropylate. The metallic compound is solved in an organic solvent and is coated on a surface to be formed with the magnetic gap spacer. The coating is heat-treated at a lower temperature to thereby form the polymer. The polymer serves as an adhesive layer for adhering the two magnetic members.

Inventors

  • 👤 Takao Maruyama

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 17:32
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/33; G11B5/39; G11B5/3903; G11B5/31

Claims Analysis

Total Claims: 24
Claim 1
Independent Claim 186 words
In a thin film magnetic head for magnetically recording and/or reading information on a magnetic recording medium comprising a first magnetic member of a soft magnetic material having a specific surface, a gap spacer layer overlying on and covering said specific surface of said first magnetic member, and a second magnetic member of a soft magnetic thin film said second magnetic member having an opposite face spaced apart from said specific surface by said gap spacer layer, each of said first and second magnetic members and said gap spacer layer having a side surface facing the magnetic recording medium and lying in the same plane, the improvement wherein said gap spacer layer consists essentially of a thermally decomposed polymer of a metallic compound represented by the following formula; M(OR1)m(R2)n-m where M denotes a metallic element selected from metals and metalloids which are elements intermediate in properties between the typical metals and non-metals, R1 indicating one selected from hydrogen and an alkyle group, R2 indicating an alkyle group, n being a valence of the metallic element, and m being an integer equal to or less than n.
Claim 2
Dependent Claim 186 words
In a thin film magnetic head for magnetically recording and/or reading information on a magnetic recording medium comprising a first magnetic member of a soft magnetic material having a specific surface, a gap spacer layer overlying on and covering said specific surface of said first magnetic member, and a second magnetic member of a soft magnetic thin film said second magnetic member having an opposite face spaced apart from said specific surface by said gap spacer layer, each of said first and second magnetic members and said gap spacer layer having a side surface facing the magnetic recording medium and lying in the same plane, the improvement wherein said gap spacer layer consists essentially of a thermally decomposed polymer of a metallic compound represented by the following formula; M(OR1)m(R2)n-m where M denotes a metallic element selected from metals and metalloids which are elements intermediate in properties between the typical metals and non-metals, R1 indicating one selected from hydrogen and an alkyle group, R2 indicating an alkyle group, n being a valence of the metallic element, and m being an integer equal to or less than n.
Claim 3
Dependent Claim 27 words
A thin film magnetic head according to claim 1, wherein said alkyl group comprises methyl, ethyl, propyl, butyl, 2-ethyl hexyl, stearyl, nonyl, cetyl, glycol, isopropylhexyleneglycol, and oleoyl.
Claim 4
Dependent Claim 25 words
A thin film magnetic head according to claim 2, wherein said metallic compound is one of tetraisopropyl titanate, tetranormalbutyl titanate, tetraalkoxysilane, organosilanol, and aluminum isopropylate.
Claim 5
Dependent Claim 21 words
A thin film magnetic head according to claim 1, wherein said gap spacer layer includes a stress relaxation agent dispersed therein.
Claim 6
Dependent Claim 19 words
A thin film magnetic head according to claim 4, wherein said stress relaxation agent is a silane coupling agent.
Claim 7
Dependent Claim 25 words
A thin film magnetic head according to claim 5, wherein said silane coupling agent is one of vinyl trichlorosilane, vinyl triethoxysilane, and vinyl tris(beta-methoxyethoxy) silane.
Claim 8
Dependent Claim 26 words
A thin film magnetic head according to claim 1, wherein said first and second magnetic members are connected to each other to form a magnetic headcore.
Claim 9
Dependent Claim 27 words
A thin film magnetic head according to claim 1, wherein said first magnetic member is a shield plate and said second magnetic member is a magnetoresistive element.
Claim 10
Dependent Claim 354 words
A thin film magnetic head for magnetically recording and/or reading information on a magnetic recording medium comprising; a first block comprising a first non-magnetic substrate, a first soft magnetic thin film overlying on said first substrate, and a first insulator guard layer overlying on said first magnetic film, said first block having a first flat side surface on which said first substrate, said first magnetic film, and said guard layer are exposed, said first block having a first contact surface on which said first substrate, said first magnetic film, and said first guard layer are also exposed, said first substrate being formed with a groove in said first contact surface; a coil being wound on said first block through said groove; a second block comprising a second non-magnetic substrate, a second soft magnetic thin film overlying on said second substrate, and a second insulator guard layer overlying on said second magnetic film, said second block having a second flat side surface on which said second substrate, said second magnetic film, and said second guard layer are exposed, said second block having a second contact surface on which said second substrate, said second magnetic film, and said second guard layer are also exposed, said second block being in contact with each other at said first and second contact surfaces with said first and second side surfaces lying in the same plane to form a sliding surface for the magnetic recording medium; a gap spacer layer being interposed between said first and second contact surfaces adjacent said first and second side surfaces, said gap spacer layer exposing in the same plane of said sliding surface, said gap spacer layer adhering said first and second blocks together, said gap spacer layer consisting essentially of a metallic compound represented by, M(OR1)m(R2)n-m where M denotes a metallic element selected from metals and metalloids which are elements intermediate in properties between the typical metals and non-metals, R1 indicating one selected from hydrogen and an alkyle group, R2 indicating an alkyle group, n being a valence of the metallic element, and m being an integer equal to or less than n.
Claim 11
Dependent Claim 354 words
A thin film magnetic head for magnetically recording and/or reading information on a magnetic recording medium comprising; a first block comprising a first non-magnetic substrate, a first soft magnetic thin film overlying on said first substrate, and a first insulator guard layer overlying on said first magnetic film, said first block having a first flat side surface on which said first substrate, said first magnetic film, and said guard layer are exposed, said first block having a first contact surface on which said first substrate, said first magnetic film, and said first guard layer are also exposed, said first substrate being formed with a groove in said first contact surface; a coil being wound on said first block through said groove; a second block comprising a second non-magnetic substrate, a second soft magnetic thin film overlying on said second substrate, and a second insulator guard layer overlying on said second magnetic film, said second block having a second flat side surface on which said second substrate, said second magnetic film, and said second guard layer are exposed, said second block having a second contact surface on which said second substrate, said second magnetic film, and said second guard layer are also exposed, said second block being in contact with each other at said first and second contact surfaces with said first and second side surfaces lying in the same plane to form a sliding surface for the magnetic recording medium; a gap spacer layer being interposed between said first and second contact surfaces adjacent said first and second side surfaces, said gap spacer layer exposing in the same plane of said sliding surface, said gap spacer layer adhering said first and second blocks together, said gap spacer layer consisting essentially of a metallic compound represented by, M(OR1)m(R2)n-m where M denotes a metallic element selected from metals and metalloids which are elements intermediate in properties between the typical metals and non-metals, R1 indicating one selected from hydrogen and an alkyle group, R2 indicating an alkyle group, n being a valence of the metallic element, and m being an integer equal to or less than n.
Claim 12
Dependent Claim 105 words
A thin film magnetic head according to claim 9, wherein said gap spacer layer is formed by a method comprising steps of; solving said metallic compound in an organic solvent to form a solution with an appropriate viscosity; applying said solution onto said first contact surface of said first block adjacent said first side surface to form a solution coating with a predetermined thickness; and heat treating said solution coating at a low temperature of 100° C.-200° C. under press of said second block onto said first block, so that said metallic compound is thermally decomposed to form the polymer with said solvent being evaporated.
Claim 13
Dependent Claim 15 words
A thin film magnetic head according to claim 10, wherein said metallic compound is organosilanol.
Claim 14
Dependent Claim 224 words
A magnetoresistive type magnetic head for magnetically recording and/or reading information on a magnetic recording medium comprising; a first magnetic shield plate having a main surface and a first plate side end for defining a sliding surface for the magnetic recording medium; an insulator layer overlying on said main surface of said first magnetic shield plate and having an insulator side end lying in the same plane of said first plate side end; a magnetoresistive element having a predetermined pattern and being formed on said insulator layer, said magnetoresistive element having an element side end lying in the same plane of said first plate side end; a second magnetic shield plate having a second plate side end lying in the same plane of said first plate side end; and a gap spacer layer adhering said second magnetic shield plate onto said magnetoresistive element and said insulator layer, said gap spacer consisting essentially of a thermally decomposed polymer of a metallic compound represented by the following formula, M(OR1)m(R2)n-m where M denotes a metallic element selected from metals and metalloids which are elements intermediate in properties between the typical metals and non-metals, R1 indicating one selected from hydrogen and an alkyle group, R2 indicating an alkyle group, n being a valence of the metallic element, and m being an integer equal to or less than n.
Claim 15
Dependent Claim 224 words
A magnetoresistive type magnetic head for magnetically recording and/or reading information on a magnetic recording medium comprising; a first magnetic shield plate having a main surface and a first plate side end for defining a sliding surface for the magnetic recording medium; an insulator layer overlying on said main surface of said first magnetic shield plate and having an insulator side end lying in the same plane of said first plate side end; a magnetoresistive element having a predetermined pattern and being formed on said insulator layer, said magnetoresistive element having an element side end lying in the same plane of said first plate side end; a second magnetic shield plate having a second plate side end lying in the same plane of said first plate side end; and a gap spacer layer adhering said second magnetic shield plate onto said magnetoresistive element and said insulator layer, said gap spacer consisting essentially of a thermally decomposed polymer of a metallic compound represented by the following formula, M(OR1)m(R2)n-m where M denotes a metallic element selected from metals and metalloids which are elements intermediate in properties between the typical metals and non-metals, R1 indicating one selected from hydrogen and an alkyle group, R2 indicating an alkyle group, n being a valence of the metallic element, and m being an integer equal to or less than n.
Claim 16
Dependent Claim 22 words
A magnetoresistive type magnetic head according to claim 12, wherein said gap spacer layer further contains a stress relaxation agent dispersed therein.
Claim 17
Dependent Claim 26 words
A magnetoresistive type magnetic head according to claim 13, wherein said stress relaxation agent is one of vinyl trichlorosilane, vinyl triethoxysilane, and vinyl tris (beta-methoxyethoxy) silane.
Claim 18
Dependent Claim 107 words
A magnetoresistive type magnetic head according to claim 12, wherein said gap spacer layer is formed by a method comprising steps of; solving said metallic compound in an organic solvent to form a solution with an appropriate viscosity; applying said solution onto said second magnetic shield plate to form a solution coating with a predetermined thickness; and heat treating said solution coating at a low temperature of 100° C.-200° C. under press of said solution coating of the second magnetic shield plate onto said insulator layer and said magnetoresistive element, so that said metallic compound is thermally decomposed to form the polymer with said solvent being evaporated.
Claim 19
Dependent Claim 327 words
A thin film magnetic head for magnetically recording and/or reading information on a magnetic recording medium comprising; a non-magnetic substrate having a main surface and a substrate side end defining a sliding surface for said magnetic recording medium; an insulator layer overlying on the main surface of said non-magnetic substrate and having an insulator side end lying in the same plane of said substrate side end; a first magnetic thin film being formed on said insulator layer and having a predetermined pattern and a first film end lying in the same plane of said substrate side end; a gap spacer layer overlying on said insulator layer and said first magnetic thin film and having a spacer end lying in the same plane of said insulator side end, said gap spacer layer consisting essentially of a thermally decomposed polymer of a metallic compound represented by the following formula, M(OR1)m(R2)n-m where M denotes a metallic element selected from metals and metalloids which are elements intermediate in properties between the typical metals and non-metals, R1 indicating one selected from hydrogen and an alkyle group, R2 indicating an alkyl group, n being a valence of the metallic element, and m being an integer equal to or less than n; a conductor layer with a coil pattern being formed on said gap spacer layer without any conductor end lying in the same plane of said substrate side end; a second magnetic film having a predetermined pattern and being formed in said gap spacer layer and said conductor layer, said second magnetic layer having a second film side end overlying on said gap spacer layer and lying in the same plane of said substrate side end, said second magnetic film being connected with said first magnetic film to form a magnetic headcore having a magnetic gap defined by said gap spacer layer interposed therebetween; and a non-magnetic guard layer overlying on said second magnetic film, said conductor layer, and said gap spacer layer.
Claim 20
Dependent Claim 327 words
A thin film magnetic head for magnetically recording and/or reading information on a magnetic recording medium comprising; a non-magnetic substrate having a main surface and a substrate side end defining a sliding surface for said magnetic recording medium; an insulator layer overlying on the main surface of said non-magnetic substrate and having an insulator side end lying in the same plane of said substrate side end; a first magnetic thin film being formed on said insulator layer and having a predetermined pattern and a first film end lying in the same plane of said substrate side end; a gap spacer layer overlying on said insulator layer and said first magnetic thin film and having a spacer end lying in the same plane of said insulator side end, said gap spacer layer consisting essentially of a thermally decomposed polymer of a metallic compound represented by the following formula, M(OR1)m(R2)n-m where M denotes a metallic element selected from metals and metalloids which are elements intermediate in properties between the typical metals and non-metals, R1 indicating one selected from hydrogen and an alkyle group, R2 indicating an alkyl group, n being a valence of the metallic element, and m being an integer equal to or less than n; a conductor layer with a coil pattern being formed on said gap spacer layer without any conductor end lying in the same plane of said substrate side end; a second magnetic film having a predetermined pattern and being formed in said gap spacer layer and said conductor layer, said second magnetic layer having a second film side end overlying on said gap spacer layer and lying in the same plane of said substrate side end, said second magnetic film being connected with said first magnetic film to form a magnetic headcore having a magnetic gap defined by said gap spacer layer interposed therebetween; and a non-magnetic guard layer overlying on said second magnetic film, said conductor layer, and said gap spacer layer.
Claim 21
Dependent Claim 91 words
A thin film magnetic head according to claim 16, wherein said gap spacer layer is formed by a method comprising steps of; solving said metallic compound in an organic solvent to form a solution with an appropriate viscosity; applying said solution onto said insulator layer and said first magnetic thin film to form a solution coating with a predetermined thickness; and heat treating said solution coating at a low temperature of 100° C.-200° C., so that said metallic compound is thermally decomposed to form the polymer with said solvent being evaporated.
Claim 22
Dependent Claim 15 words
A thin film magnetic head according to claim 17, wherein said metallic compound is tetrahydroxysilane.
Claim 23
Dependent Claim 22 words
A thin film magnetic head according to claim 16, wherein said gap spacer layer further contains a stress relaxation agent dispersed therein.
Claim 24
Dependent Claim 26 words
A thin film magnetic head according to claim 19, wherein said stress relaxation agent is one of vinyl trichlorosilane, vinyl triethoxysilane, and vinyl tris (beta-methoxyethoxy) silane.

References Cited (Backward Citations)

US3700827A Cited
US3940797A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-06-07 1991-12-07 1992-06-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-06-07 1995-12-07 1996-06-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-06-07 1999-12-07 2000-06-07 $7700.00 Window Closed / Lapsed

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