Magnetic Recording Medium Temperature Stability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Magnetic recording media containing ε-iron oxide powder deteriorate in electromagnetic conversion characteristics when used under varying temperature conditions, such as room temperature and higher temperatures, necessitating a solution to maintain performance across different temperatures.

Innovation Solution

A magnetic recording medium with a non-magnetic support and a magnetic layer containing ε-iron oxide powder, where the vertical squareness ratio (SQ) is maintained between 0.50 and 0.95 at 25°C, and the inclination of SQ is within specific ranges across different temperatures, ensuring minimal deterioration in electromagnetic conversion characteristics.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a magnetic recording medium contains ε-iron oxide powder as ferromagnetic powder, then electromagnetic conversion characteristics are improved, but deterioration occurs when used under varying temperature conditions

Engineering Contradiction:
Improveelectromagnetic conversion characteristicsVSAvoidelectromagnetic conversion characteristics stability under temperature variation
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The patent applies parameter changes by precisely controlling the vertical squareness ratio (SQ) to be 0.50 or more and 0.95 or less at 25°C, and controlling the inclination of SQ to be within -0.0050°C⁻¹ to -0.0003°C⁻¹. These specific parameter ranges optimize the magnetic layer's response to temperature variations, maintaining electromagnetic conversion characteristics across different operating temperatures.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent uses composite materials by combining ε-iron oxide powder with specific binders and additives in the magnetic layer. This composite structure allows the magnetic recording medium to maintain its electromagnetic conversion characteristics while resisting deterioration under varying temperature conditions through the synergistic effects of different materials.

Inventive Principle:
Principle #40Composite materials

2Use of energy by stationary object

If temperature control conditions are relaxed to save power in data centers, then energy consumption is reduced, but electromagnetic conversion characteristics deteriorate

Engineering Contradiction:
Improvepower consumption for temperature controlVSAvoidelectromagnetic conversion characteristics
Core Design Contradiction:
Use of energy by stationary objectVSReliability

Solution Approach 1:

The patent changes the operational parameters by defining specific ranges for vertical squareness ratio (0.50-0.95 at 25°C) and SQ inclination (-0.0050°C⁻¹ to -0.0003°C⁻¹), which enable the magnetic recording medium to function reliably across a broader temperature range, thereby allowing relaxed temperature control conditions.

Inventive Principle:
Principle #35Parameter changes

3Reliability

If the vertical squareness ratio SQ is increased to improve electromagnetic conversion characteristics, then recording performance is improved, but sensitivity to temperature variations increases

Engineering Contradiction:
Improveelectromagnetic conversion characteristicsVSAvoidtemperature sensitivity
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent applies parameter changes by optimizing both the vertical squareness ratio (0.50-0.95) and its temperature coefficient (inclination: -0.0050°C⁻¹ to -0.0003°C⁻¹). This dual parameter optimization ensures high electromagnetic conversion characteristics while minimizing temperature sensitivity through controlled material properties.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The solution effectively suppresses deterioration in electromagnetic conversion characteristics, enabling reliable performance under different temperature conditions, which is crucial for data storage applications in environments with varying temperatures.

Implementation Method 1

a magnetic layer containing a ferromagnetic powder, in which the ferromagnetic powder is an ε-iron oxide powder

Methodology Applied
Scientific EffectFerromagnetism: Ferromagnetism

Implementation Method 2

magnetic recording and reproducing device

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentUS12014759B2Magnetic recording medium, magnetic tape cartridge, and magnetic recording and reproducing device
Publication Date: 2024.06.18 FUJIFILM CORP

AI summary

Provided are: a magnetic recording medium including a non-magnetic support and a magnetic layer containing a ferromagnetic powder, in which the ferromagnetic powder is an ε-iron oxide powder, a vertical squareness ratio SQ of the magnetic recording medium is 0.50 or more and 0.95 or less at a measurement temperature of 25° C., and an inclination of SQ obtained from SQ at a measurement temperature of 10° C., SQ at a measurement temperature of 25° C., and SQ at a measurement temperature of 40° C. is −0.0050° C.−1 or more and −0.0003° C.−1 or less; a magnetic tape cartridge including the magnetic recording medium which is a magnetic tape; and a magnetic recording and reproducing device including the magnetic recording medium.