Charging Member Surface Layer Electron Emission Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Contact type charging members in image forming apparatuses experience charging unevenness due to electrical irregularities, leading to image defects such as colored spots and streaks, particularly when using DC charging methods and thicker charge transport layers or slower rotation speeds.
Innovation Solution
A charging member with a conductive support and a surface layer having an electron emitting energy of equal to or less than 10 cps0.5/eV, incorporating phosphor-doped tin oxide-containing conductive materials to control electron emission characteristics and prevent charging unevenness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If DC charging method is used, then charging efficiency is improved, but charging unevenness occurs leading to image defects
Solution Approach 1:
The invention changes the electrical parameter of the surface layer by controlling its volume resistivity to be within a specific range (10^8 to 10^14 Ω·cm). This parameter optimization allows the surface layer to effectively control electron emission and discharging behavior, enabling uniform charging even under DC charging conditions, thus resolving the contradiction between charging efficiency and charging uniformity
Solution Approach 2:
The invention uses a composite structure consisting of a conductive support and a surface layer made of charge transport material. This composite design allows the surface layer to modulate electron emission characteristics while the conductive support provides structural stability and electrical conductivity, solving the charging unevenness problem while maintaining high charging efficiency
2Quantity of substance
If thicker charge transport layers are used, then charge transport capacity is improved, but charging unevenness increases
Solution Approach 1:
The invention optimizes the volume resistivity parameter of the surface layer to a specific range that compensates for the increased thickness effect. By controlling the electrical properties rather than the physical dimensions, the invention maintains uniform charging performance even with thicker charge transport layers, resolving the contradiction between charge transport capacity and charging uniformity
3Manufacturing precision
If slower rotation speeds are used, then image quality is improved, but charging unevenness occurs
Solution Approach 1:
The invention changes the electrical parameter (volume resistivity) of the surface layer to control electron emission characteristics. This allows the system to maintain stable charging performance across different rotation speeds, enabling slower speeds for better image quality without suffering from charging unevenness that normally occurs at low speeds
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 prevents charging unevenness and associated image defects by controlling electron emission and discharging, even when using thicker charge transport layers or slower rotation speeds, ensuring consistent image quality.
Implementation Method 1
electron emitting energy on a surface of the charging member is equal to or less than 10 cps0.5/eV
Data Source
AI summary
A charging member includes a conductive support and a surface layer provided on the conductive support, wherein electron emitting energy on a surface of the charging member is equal to or less than 10 cps0.5/eV.