IP Library Granted Patent US 7,842,331
Granted Patent B2
US 7,842,331 · App. 11/892,217 · Granted Nov 30, 2010

Manufacturing method and evaluating method of magnetic recording medium

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Quick Facts
Patent No.
US 7,842,331
App. No.
11/892,217
Granted
Nov 30, 2010
Kind
B2
Abstract

A manufacturing method of a magnetic recording medium having a surface where a lubricating layer is provided, the manufacturing method includes the steps of: applying a lubricant so that the lubricating layer is formed; and inspecting the magnetic recording medium where the lubricating layer is formed; wherein the step of inspecting includes a first step of floating a magnetic head over the magnetic recording medium or sliding the magnetic head on a surface of the magnetic recording medium; a second step of adhering a medium facing surface of the magnetic head to a surface of a substrate for measuring, standing the medium facing surface of the magnetic head on the surface of the substrate for measuring, and transferring the lubricant from the medium facing surface of the magnetic head to the substrate for measuring; a third step of measuring an amount of the lubricant on the surface of the substrate for measuring; and a fourth step of determining whether the amount of the lubricant is proper.

Claims (28)

1. A manufacturing method of a magnetic recording medium having a surface where a lubricating layer is provided, the manufacturing method comprising the steps of:

applying a lubricant so that the lubricating layer is formed; and

inspecting the magnetic recording medium where the lubricating layer is formed;

wherein the step of inspecting includes

a first step of floating a magnetic head over the magnetic recording medium or sliding the magnetic head on a surface of the magnetic recording medium;

a second step of adhering a medium facing surface of the magnetic head to a surface of a substrate for measuring, standing the medium facing surface of the magnetic head on the surface of the substrate for measuring, and transferring the lubricant from the medium facing surface of the magnetic head to the substrate for measuring;

a third step of measuring an amount of the lubricant on the surface of the substrate for measuring; and

a fourth step of determining whether the amount of the lubricant is proper.

2. The manufacturing method of the magnetic recording medium as claimed in claim 1 ,

wherein the substrate for measuring in the second step has a surface where a protection film made of carbon is provided, and

the protection film is exposed.

3. The manufacturing method of the magnetic recording medium as claimed in claim 2 ,

wherein the surface of the protection film is nitrided.

4. The manufacturing method of the magnetic recording medium as claimed in claim 3 ,

wherein the amount of nitrogen of the surface of the protection film is equal to or greater than 10 at % and equal to or smaller than 15 at %.

5. The manufacturing method of the magnetic recording medium as claimed in claim 1 ,

wherein, in the second step, transferring is performed at a temperature equal to or greater than 20° C. and equal to or less than 30° C.

6. The manufacturing method of the magnetic recording medium as claimed in claim 1 ,

wherein, in the second step, standing is performed for 60 minutes or more.

7. The manufacturing method of the magnetic recording medium as claimed in claim 1 ,

wherein, in the third step, the amount of the lubricant is measured by an X-ray electron spectroscopy method, a Fourier transform infrared spectroscopy method, or an ellipsometry method.

8. The manufacturing method of the magnetic recording medium as claimed in claim 1 ,

wherein, in the third step, distribution of the amount of the lubricant is measured with relation to the position of the medium facing surface.

9. An evaluating method of a magnetic recording medium, comprising the step of:

a first step of floating a magnetic head over the magnetic recording medium having a surface where a lubricating layer is formed or sliding the magnetic head on the surface of the magnetic recording medium;

a second step of contacting a medium facing surface of the magnetic head to a surface of a substrate for measuring, standing the medium facing surface of the magnetic head on the surface of the substrate for measuring, and transferring a lubricant from the medium facing surface of the magnetic head to the substrate for measuring;

a third step of measuring an amount of the lubricant on the surface of the substrate for measuring; and

a fourth step of determining whether the amount of the lubricant is proper.

Assignments (5)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 15, 2024
From: RESONAC CORPORATION
To: RESONAC HARD DISK CORPORATION
Reel/Frame 069167/0673 →
CHANGE OF ADDRESS Recorded Feb 14, 2024
From: RESONAC CORPORATION
To: RESONAC CORPORATION
Reel/Frame 066599/0037 →
CHANGE OF NAME Recorded Jun 23, 2023
From: SHOWA DENKO K.K.
To: RESONAC CORPORATION
Reel/Frame 064082/0513 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 4, 2010
From: FUJITSU LIMITED
To: SHOWA DENKO K.K.
Reel/Frame 023950/0008 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Aug 21, 2007
From: YAMAKAWA, EISHIN; OKADA, MAKOTO; FUJII, JUN; YAMAUCHI, TAKAKO
To: FUJITSU LIMITED
Reel/Frame 019771/0734 →