Monolayer Photoreceptor and Core-Shell Toner for Stable Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrophotographic apparatuses using toner with a core-shell structure experience a decrease in transfer efficiency after endurance, leading to a decrease in image quality due to peeling of the shell structure and reduced positive chargeability of the toner.
Innovation Solution
An electrophotographic apparatus with a monolayer photosensitive layer containing a charge generating substance, a hole transporting substance, and a binder resin, where the binder resin includes a polyarylate resin with specific structural units, and toner particles with a core-shell structure having a melamine resin or similar, to enhance positive chargeability and stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If toner with a core-shell structure using melamine resin or oxazoline group is used to improve positive chargeability and charging stability, then image quality is improved from initial stage to after endurance, but transfer efficiency decreases after endurance due to shell peeling
Solution Approach 1:
The patent changes the chemical composition parameters of the shell resin by introducing a specific structural unit (formula 3 with R1 representing hydrogen or alkyl group) combined with melamine resin. This parameter change modifies the shell's adhesion properties and chargeability, preventing shell peeling while maintaining high positive chargeability throughout the service life, thus resolving the contradiction between charging stability and transfer efficiency
Solution Approach 2:
The patent uses a composite shell structure combining melamine resin with a resin containing the specific structural unit (formula 3). This composite material approach creates a shell that leverages the chargeability of melamine resin while the formula 3 component provides enhanced adhesion to prevent peeling, simultaneously achieving both charging stability and maintained transfer efficiency after endurance
2Reliability
If shell structure is used to improve positive chargeability, then charging stability is improved, but shell peeling occurs after endurance leading to decreased transfer efficiency
Solution Approach 1:
The patent modifies the shell resin composition by incorporating a specific structural unit (formula 3) with controlled R1 groups (hydrogen or alkyl). This parameter change enhances the chemical bonding strength and adhesion of the shell to the core, preventing shell peeling while preserving the shell's function in providing positive chargeability, thus maintaining both chargeability and structural stability after endurance
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 configuration suppresses the decrease in transfer efficiency after endurance, maintaining high image quality from the initial stage to the stage after endurance by increasing the positive chargeability of the toner.
Implementation Method 1
an exposing unit configured to irradiate the charged surface of the electrophotographic photosensitive member with light to form an electrostatic latent image on the surface of the electrophotographic photosensitive member
Implementation Method 2
a monolayer type photosensitive layer containing a charge generating substance, a hole transporting substance, an electron transporting substance, and a binder resin
Data Source
AI summary
An electrophotographic apparatus including an electrophotographic photosensitive member, a charging unit that charges a surface of the electrophotographic photosensitive member, an exposing unit that irradiates the charged surface of the electrophotographic photosensitive member with light to form an electrostatic latent image on the surface of the electrophotographic photosensitive member, and a developing unit, which includes toner, and which develops the electrostatic latent image formed on the surface of the electrophotographic photosensitive member with the toner to form a toner image on the surface of the electrophotographic photosensitive member. The electrophotographic photosensitive member includes a monolayer type photosensitive layer containing a charge generating substance, a hole transporting substance, an electron transporting substance, and a binder resin. The photosensitive layer contains, as the binder resin, a polyarylate resin having a structural unit represented by the following formula (1) and a structural unit represented by the following formula (2).