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US 2002/0160105 A1Published application
Magnetic recording media and coating methods
AssigneeImation Corp.
InventorsWilliam Blake Kolb, Gary L. Huelsman
Life of this patent
Estimating the term…
Abstract
A method is provided for coating one or more fluid layers on a substrate to form magnetic recording media such as magnetic tape and diskettes. The method takes advantage of fluid coating formulations having a particular rheology that enables the coating of one or more magnetic layers with reduced thicknesses while achieving increased coating speeds. With proper rheology, one or more layers can be coated on a substrate traveling at increased speeds while maintaining desired coating thicknesses.
Claims85
A method for forming a magnetic recording medium, the method comprising:
- flowing a first fluid coating formulation over a first slide coating surface of a slide coater;
- flowing a second fluid coating formulation containing metal magnetic recording particles over a second slide coating surface of the slide coater and over the first coating formulation, the first and second coating formulations forming a multi-layer coating;
- and
- flowing the multi-layer coating onto a moving substrate to simultaneously apply the first and second coating formulations to the substrate,
- wherein the first coating formulation has a wet viscosity of approximately 4 to 10 cp at a shear rate of approximately 9000 to 11000 sec−1.
2 more elements
A method for forming a magnetic recording medium, the method comprising:
- moving a substrate relative to a slide coating surface;
- flowing a first fluid coating formulation over a first slide coating surface of a slide coater;
- flowing a second fluid coating formulation containing metal magnetic recording particles over a second slide coating surface of the slide coater and over the first coating formulation, the first and second coating formulations forming a multi-layer coating on substrate;
- and
- flowing the multi-layer coating onto the substrate to simultaneously apply the first and second coating formulations to the substrate,
- wherein the multi-layer coating has an average wet thickness on the substrate of less than approximately 25 micrometers.
3 more elements
A method for forming a magnetic recording medium, the method comprising:
- moving a substrate relative to a slide coating surface;
- flowing a first fluid coating formulation containing metal magnetic recording particles over a first slide coating surface of a slide coater;
- flowing a second fluid coating formulation containing metal magnetic recording particles over a second slide coating surface of the slide coater and over the first coating formulation, the first and second coating formulations forming a multi-layer coating;
- flowing the multi-layer coating onto the substrate to simultaneously apply the first and second coating formulations to the substrate;
- and
- drying the multi-layer coating on the substrate to form a film, wherein the film has a dry thickness of less than approximately 3 micrometers before calendaring.
3 more elements
A method for forming a magnetic recording medium, the method comprising:
- moving a substrate relative to a slide coating surface;
- flowing a first fluid coating formulation over a first slide coating surface of a slide coater;
- flowing a second fluid coating formulation over a second slide coating surface of the slide coater and over the first coating formulation;
- flowing a third fluid coating formulation over a third slide surface and over the first and second coating formulations, the first, second, and third coating formulations forming a multi-layer coating, wherein one of the first, second, and third coating formulations contains metal magnetic recording particles;
- and
- flowing the multi-layer coating onto the substrate to simultaneously apply the first, second, and third coating formulations to the substrate, wherein the first coating formulation has a wet viscosity of approximately 4 to 10 cp at a shear rate of approximately 9000 to 11000 sec−1.
3 more elements
A method for forming a magnetic recording medium, the method comprising:
- moving a substrate relative to a slide coating surface;
- flowing a first liquid coating formulation containing metal magnetic recording particles over a first slide coating surface of a slide coater;
- flowing a second liquid coating formulation over a second slide coating surface of the slide coater and over the first coating formulation;
- flowing a third liquid coating formulation over a third slide surface and over the first and second coating formulations, the first, second, and third coating formulations forming a multi-layer coating, wherein one of the first, second, and third coating formulations contains metal magnetic recording particles;
- flowing the multi-layer coating onto the substrate to simultaneously apply the first, second, and third coating formulations to the substrate, wherein the first coating formulation has a wet viscosity of approximately 4 to 10 cp at a shear rate of approximately 9000 to 11000 sec−1, approximately 20 to 150 cp at a shear rate of approximately 75 to 100 sec−1, and greater than or equal to approximately 50 cp at a shear rate of approximately 3 to 5 sec−1;
- and
- drying the multi-layer coating on the substrate to form a film, wherein the film has a thickness on the substrate of less than approximately 3 micrometers before calendaring.
4 more elements
A method for forming a magnetic recording medium, the method comprising:
- moving a substrate relative to a single coater;
- flowing a first fluid coating formulation containing metal magnetic recording particles out of a first outlet in the single coater;
- flowing a second fluid coating formulation containing metal magnetic recording particles out of a second outlet in the single coater and over the over the first coating formulation;
- flowing a third fluid coating formulation containing metal magnetic recording particles out of a third outlet in the single coater and over the first and second coating formulations, the first, second, and third coating formulations forming a multi-layer coating;
- and
- flowing the multi-layer coating onto the substrate to simultaneously apply the first, second, and third coating formulations to the substrate.
3 more elements
67 The method of claim 57, further comprising moving the substrate relative to the first, second, and third slide surfaces at a rate of greater than approximately 120 meters per minute.
A system for forming a magnetic recording medium, the system comprising:
- means for flowing a first fluid coating formulation over a first slide coating surface of a slide coater;
- means for flowing a second fluid coating formulation containing metal magnetic recording particles over a second slide coating surface of the slide coater and over the first coating formulation, the first and second coating formulations forming a multi-layer coating;
- and
- means for flowing the multi-layer coating onto a moving substrate to simultaneously apply the first and second coating formulations to the substrate,
- wherein the first coating formulation has a wet viscosity of approximately 4 to 10 cp at a shear rate of approximately 9000 to 11000 sec−1.
2 more elements
A system for forming a magnetic recording medium, the system comprising:
- means for moving a substrate relative to a slide coating surface;
- means for flowing a first fluid coating formulation over a first slide coating surface of a slide coater;
- means for flowing a second fluid coating formulation containing metal magnetic recording particles over a second slide coating surface of the slide coater and over the first coating formulation, the first and second coating formulations forming a multi-layer coating;
- and
- means for flowing the multi-layer coating onto the substrate to simultaneously apply the first and second coating formulations to the substrate,
- wherein the multi-layer coating has an average wet thickness on the substrate of less than approximately 25 micrometers.
3 more elements
A system for forming a magnetic recording medium, the system comprising:
- means for moving a substrate relative to a single coater;
- means for flowing a first fluid coating formulation containing metal magnetic recording particles out of a first outlet in the single coater;
- means for flowing a second fluid coating formulation containing metal magnetic recording particles out of a second outlet in the single coater and over the first coating formulation;
- means for flowing a third fluid coating formulation containing metal magnetic recording particles out of a third outlet in the single coater and over the first and second coating formulations, the first, second, and third coating formulations forming a multi-layer coating;
- and
- means for flowing the multi-layer coating onto the substrate to simultaneously apply the first, second, and third coating formulations to the substrate,
- wherein the first coating formulation has a wet viscosity of approximately 4 to 10 cp at a shear rate of approximately 9000 to 11000 sec−1,
4 more elements
Dependencies are inferred from the claim text.