Poly(imide-carbonate) Charge Transport Layer Wear Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing photoconductors face issues with wear rates, ghosting, and cyclic stability in xerographic copying and printing systems, particularly at varying humidities, due to the limitations of charge transport layers without poly(imide-carbonate) and fluorinated polymers.
Innovation Solution
A photoconductor comprising a supporting substrate, a photogenerating layer, and a charge transport layer with a poly(imide-carbonate) copolymer and polytetrafluoroethylene (PTFE) as key components, which reduces wear rates and minimizes ghosting and cyclic instability by enhancing the compatibility and electrical properties of the charge transport layer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional charge transport layers are used in photoconductors, then the basic charge transport function is maintained, but wear rates increase and cyclic stability deteriorates at varying humidities
Solution Approach 1:
The patent employs a composite charge transport layer comprising polycarbonate resin binder, fluorinated polymer (such as polytetrafluoroethylene or polyvinylidene fluoride), and charge transport compound. This composite structure combines the electrical properties of polycarbonate, the wear resistance of fluorinated polymers, and the charge transport capability of the charge transport compound, thereby simultaneously improving cyclic stability and reducing wear rates under varying humidity conditions.
2Stability of the object's composition
If the charge transport layer composition is modified to improve wear resistance, then wear rates decrease, but ghosting and cyclic instability increase
Solution Approach 1:
The patent optimizes the weight ratio parameters of the charge transport layer components, specifically maintaining fluorinated polymer at 1-20 parts by weight per 100 parts of polycarbonate resin binder, and charge transport compound at 20-80 parts by weight per 100 parts of polycarbonate resin binder. This parameter optimization ensures sufficient wear resistance while preventing ghosting and cyclic instability by balancing the composition proportions.
Solution Approach 2:
The patent introduces a hole blocking layer with specific properties (resistivity of 10^8-10^12 Ω·cm and thickness of 1-10 μm) positioned between the substrate and photogenerating layer. This layer provides localized charge control to prevent harmful charge accumulation that causes ghosting, while the fluorinated polymer in the charge transport layer provides localized wear resistance at the surface.
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 incorporation of poly(imide-carbonate) and PTFE in the charge transport layer significantly reduces wear rates, minimizes ghosting, and maintains stable electrical properties across different humidity levels, improving the overall performance and longevity of the photoconductor in xerographic systems.
Implementation Method 1
a photogenerating layer, and wherein the charge transport layer contains a poly(imide-carbonate) copolymer and polytetrafluoroethylene (PTFE)
Data Source
AI summary
A photoconductor that includes for example, a supporting substrate, an optional ground plane layer, an optional hole blocking layer, an optional adhesive layer, a photogenerating layer, and a charge transport layer, and where the charge transport layer contains a charge transport component, and a mixture of a poly(imide-carbonate) polymer and a fluorinated polymer and optionally a third polymer, like a polycarbonate.