Aluminum Photosensitive Member Surface Control for Stable Imaging

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing electrophotographic photosensitive members suffer from image defects and long-term potential fluctuations due to surface roughness of the support, which are not adequately addressed by existing surface treatments.

Innovation Solution

The surface of the support is treated to achieve an IR peak area ratio A ≥ 0.75, determined by Fourier transform infrared spectroscopy, to suppress image defects and reduce long-term potential fluctuations, using methods such as immersion in pure water at specific temperatures and times, and applying conductive and undercoat layers.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If the surface of the support is treated to reduce roughness to suppress image defects, then image quality is improved, but long-term potential fluctuation increases

Engineering Contradiction:
Improvesurface roughnessVSAvoidlong-term potential fluctuation
Core Design Contradiction:
Manufacturing precisionVSReliability

Solution Approach 1:

The patent applies parameter changes by controlling the IR peak area ratio A to be 0.50 or more, which corresponds to specific surface treatment conditions (immersion in pure water at 91-98°C for 60-300 seconds). This parameter control optimizes the surface state to simultaneously achieve image defect suppression and long-term potential stability

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent uses a composite approach by combining the support surface with specific layers (conductive layer, undercoat layer, photosensitive layer) where each layer has specific compositional requirements. The support surface contains Al and/or Al alloy with controlled oxidation state, creating a multi-layer composite structure that balances image quality and electrical stability

Inventive Principle:
Principle #40Composite materials

2Manufacturing precision

If existing surface treatment methods are applied to the support, then image defects are suppressed, but long-term potential fluctuation becomes large

Engineering Contradiction:
Improvesurface uniformityVSAvoidpotential stability
Core Design Contradiction:
Manufacturing precisionVSReliability

Solution Approach 1:

The patent introduces a new control parameter (IR peak area ratio A ≥ 0.50) that differs from conventional treatment methods. This parameter change represents a shift in the oxidation state control of the support surface, achieving a balance between surface uniformity for image quality and electrical stability for potential consistency

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent applies preliminary action by performing specific surface treatment (immersion in pure water at 91-98°C for 60-300 seconds) before forming the photosensitive layer. This preliminary treatment establishes the optimal surface state (IR peak area ratio A ≥ 0.50) that prevents both image defects and long-term potential fluctuation

Inventive Principle:
Principle #10Preliminary action

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 treatment effectively suppresses image defects and reduces long-term potential fluctuations, enhancing the performance and reliability of the electrophotographic photosensitive member.

Implementation Method 1

an IR peak area ratio A of the surface of the support determined by Fourier transform infrared spectroscopy satisfies the following condition: A≥0.50

Methodology Applied
Scientific EffectFourier transform infrared spectroscopy: Absorption Spectroscopy

Data Source

PatentEP4050417B1Electrophotographic photosensitive member, process cartridge, electrophotographic apparatus, and method of manufacturing electrophotographic photosensitive member
Publication Date: 2026.04.08 CANON KK
  • EP4050417B1 patent drawingFigure 1
  • EP4050417B1 patent drawingFigure 2
  • EP4050417B1 patent drawing

AI summary

Provided is an electrophotographic photosensitive member that suppresses an image defect resulting from its support and is reduced in long-term potential fluctuation. The electrophotographic photosensitive member is an electrophotographic photosensitive member including a support having a cylindrical shape and a photosensitive layer formed on the support, wherein the support has a surface formed of Al and/or an Al alloy, and wherein the IR peak area ratio A of the surface of the support determined by Fourier transform infrared spectroscopy satisfies the following condition: A≥0.50 where the IR peak area ratio A represents a ratio a/z of a peak area "a" in the range of from 1,016 cm-1 or more to 1,130 cm-1 or less to a peak area "z" in the range of from 650 cm-1 or more to 1,130 cm-1 or less.