Emulsion Aggregation Toner Surface Oxygen Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing emulsion aggregation toner compositions suffer from print defects such as marks and smears on high area coverage prints due to inadequate control over the amount of wax on the surface of toner particles.

Innovation Solution

The development of toner particles with a controlled surface composition, specifically limiting the atomic percent oxygen to less than 15, achieved by optimizing the wax content and processing conditions, including the use of waxes like POLYWAX 655 and POLYWAX 725, to ensure appropriate wax distribution and minimize print defects.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the amount of wax on the surface of EA toner particles is increased, then release from the fuser roll is improved, but marks on copy print defects increase

Engineering Contradiction:
Improverelease from fuser rollVSAvoidmarks on copy print defects
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The invention changes the surface composition parameter by controlling the atomic percent oxygen to less than 15%, which corresponds to optimizing the wax content on the particle surface. This parameter change resolves the contradiction by finding the optimal balance point where sufficient wax provides release properties while preventing excessive wax that causes marks on copy prints

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention replaces direct measurement and control of wax content with an indirect measurement method using atomic percent oxygen analysis. This substitution allows for more precise control of the wax-related surface properties without the complexity of directly measuring wax distribution, thereby resolving the contradiction between release properties and mark prevention

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Object-generated harmful factors

If the atomic percent oxygen on the surface of toner particles is reduced, then print defects are reduced, but measurement and control complexity increases

Engineering Contradiction:
Improveprint defectsVSAvoidatomic percent oxygen measurement
Core Design Contradiction:
Object-generated harmful factorsVSDifficulty of detecting and measuring

Solution Approach 1:

The invention uses atomic percent oxygen as an intermediary parameter to control wax content on the particle surface. Instead of directly measuring and controlling wax distribution, the patent measures oxygen content as a proxy, which simplifies the control process while achieving the desired reduction in print defects

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The invention implements a feedback control mechanism where atomic percent oxygen measurement results are used to adjust and control the wax content in subsequent production batches. This feedback loop enables consistent production of toner particles with optimal surface composition, reducing print defects while maintaining measurable control

Inventive Principle:
Principle #23Feedback

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 controlled surface oxygen level reduces print defects, allowing for improved image quality with reduced marks on copy prints, enhancing the reliability and performance of toner particles in various development systems.

Implementation Method 1

a surface of the toner particles comprises less than 15 atomic percent oxygen in relation to a total atomic percent of 100 for all elements on the surface of the toner particles

Methodology Applied
Scientific EffectSurface composition control:

Data Source

PatentUS7910276B2Toner compositions
Publication Date: 2011.03.22 XEROX CORP

AI summary

Disclosed herein are emulsion aggregation toner particles having less than about 15 atomic percent oxygen in relation to a total atomic percent of 100 for all elements on the surface thereof. Such toner particles exhibit lower marks on print defects.