Development Roller Surface Free Energy for Toner Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Contact type nonmagnetic one-component development devices face challenges in maintaining a stable development bias setting range that balances target image density and effective cleaning of undeveloped toner over time.
Innovation Solution
The development device incorporates a development roller with a surface free energy between 5 mJ/m2 and 27 mJ/m2, a supply roller, and a layer thickness regulating member, allowing for controlled toner supply and collection, which adjusts the development bias and pressing force to achieve optimal image density and cleaning performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the development roller surface free energy is increased to improve toner carrying force and image density, then image density is improved, but the cleaning property of undeveloped toner deteriorates and afterimage generation increases
Solution Approach 1:
The patent applies parameter changes by precisely controlling the surface free energy of the development roller within a specific range (5-27 mJ/m2) to optimize the balance between toner carrying force and cleaning property. This quantitative parameter control resolves the contradiction by finding the optimal value range that satisfies both image density and cleaning requirements
2Manufacturing precision
If the development bias is increased to improve image density, then image density is improved, but the stability of development performance over time deteriorates
Solution Approach 1:
The patent uses parameter changes by optimizing the development bias voltage within a specific range (-50 to -200 V) combined with controlled surface free energy to expand the stable development bias setting range. This allows maintaining target image density while ensuring stable cleaning performance over extended operation periods
3Manufacturing precision
If the contact pressure between development roller and photosensitive drum is increased to improve toner transfer, then image density is improved, but the cleaning property deteriorates and white voids occur
Solution Approach 1:
The patent applies parameter changes by controlling the surface free energy of the development roller to optimize the interaction between toner and development roller surface. This allows achieving sufficient toner transfer at moderate contact pressures without causing cleaning failures or white voids, thus resolving the contradiction between image density and cleaning property
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
This configuration ensures a wider usable range for development bias and pressing force, stabilizing image formation and preventing issues like white voids and cleaning failures, thereby maintaining image quality and efficiency in a simple and low-cost setup.
Implementation Method 1
the toner is directly rubbed by the supply roller to the development roller to be triboelectrically charged
Implementation Method 2
the toner is attracted to the development roller and conveyed to the photosensitive drum by the development roller
Data Source
AI summary
A development device includes a development housing, a development roller, a supply roller and a layer thickness regulating member. The development housing stores a nonmagnetic one-component toner. The development roller is formed by a cylindrical elastic body, and moves in a same direction as a rotational direction of a rotatable photosensitive drum at a development nip area while coming into contact with the photosensitive drum. The supply roller is formed by a cylindrical elastic body, and supplies the toner to the development roller and collects the toner from the development roller. The development roller has a surface free energy within a range of 5 mJ/m2 or more and 27 mJ/m2 or less.