Electro-conductive Member Matrix-Domain Structure for Compression Set
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electro-conductive members for electrophotography suffer from deformation issues due to compression set, leading to uneven discharge and streaks in electrophotographic images, as they tend to lose elasticity with the incorporation of electro-conductive particles, which affects their recoverability and discharge stability, especially at high printing speeds.
Innovation Solution
An electro-conductive member with a matrix-domain structure comprising a cross-linked first rubber matrix and electro-conductive domains, where the first and second rubbers have different monomer units and solubility parameters, and a specific ratio of loss factors, allowing for improved mechanical distortion resistance and uniform discharge by dispersing electro-conductive particles effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If electro-conductive particles are incorporated into the rubber composition to enhance electro-conductivity, then the electro-conductive performance is improved, but the elasticity and recoverability of the rubber are degraded
Solution Approach 1:
The rubber composition is segmented into a matrix phase (first rubber composition) and dispersed domains (second rubber composition with electro-conductive particles). This segmentation allows the matrix to provide elasticity and recoverability while the domains provide electro-conductivity, resolving the contradiction between these opposing properties.
Solution Approach 2:
The invention uses a composite rubber composition consisting of two different rubber materials with specific solubility parameter differences. This composite structure enables the material to simultaneously exhibit the elastic properties of the matrix rubber and the electro-conductive properties of the domain rubber, overcoming the limitation of single-rubber systems.
2Reliability
If the rubber composition is optimized for electro-conductivity, then discharge performance is improved, but resistance to mechanical distortion and compression set increases
Solution Approach 1:
By segmenting the rubber composition into matrix and domain phases with different functional priorities, the matrix is optimized for mechanical strength and distortion resistance while the domains are optimized for electro-conductivity and discharge performance, allowing both requirements to be satisfied simultaneously.
Solution Approach 2:
Different regions of the rubber composition have different local qualities: the matrix region provides mechanical strength and distortion resistance, while the domain regions provide electro-conductivity. This local differentiation resolves the contradiction between overall mechanical strength and electro-conductive performance.
3Manufacturing precision
If electro-conductive particles are added to improve charging uniformity, then image quality is improved, but compression set occurs leading to streaks
Solution Approach 1:
The segmentation of electro-conductive particles into discrete domains within an elastic matrix prevents the particles from causing overall compression set while maintaining localized electro-conductivity. This resolves the contradiction between achieving uniform charging and preventing compression set streaks.
Solution Approach 2:
The composite rubber composition with two different rubber materials creates a structure where the domain phase provides electro-conductivity for uniform charging while the matrix phase provides elasticity to prevent compression set, eliminating the harmful streaks while maintaining charging uniformity.
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 electro-conductive member with a matrix-domain structure enhances the mechanical properties and electro-conductivity, reducing deformation and ensuring stable discharge even under high-speed processes, thereby preventing streaks and maintaining image quality.
Implementation Method 1
a matrix-domain structure that includes a continuous phase of a polymer which is formed from an ion-conductive rubber material mainly formed from a raw rubber A having a volume specific resistivity of 1×1012 Ω·cm or smaller, and a particle phase of a polymer which is formed from an electron conductive rubber material
Implementation Method 2
a particle phase of a polymer which is formed from an electron conductive rubber material that has been made electro-conductive by an electro-conductive particle blended in a raw rubber B
Implementation Method 3
a charging member having an elastic layer that is formed from the rubber composition
Data Source
AI summary
The electro-conductive member has an electro-conductive support, and an electro-conductive layer in this order, the electro-conductive layer including a matrix and domains, the matrix constituted by a first rubber composition containing a cross-linked product of a first rubber, the domains having electro-conductivity, and dispersed in the matrix, each of the domains constituted by a second rubber composition containing a cross-linked product of a second rubber and an electro-conductive particle, the first rubber and the second rubber being diene-based rubbers, the first rubber having at least one monomer unit, the second rubber having at least one monomer unit different from the monomer unit which the first rubber has; a difference of absolute values of SP values between the first rubber and the second rubber is 0.2 (J/cm3)0.5 to 4.0 (J/cm3)0.5; and a tan δ1/tan δ2 is 0.45 to 2.00.