Toner Particle with Nested Release Agent for Image Quality

Solution Overview

Problem

In electrophotography, the exposure of release agents on the surface of toner particles due to abrasion leads to toner solidification and image deletion, particularly in high temperature and high humidity environments, especially when forming images with high density after continuously printing low-density images.

Innovation Solution

The development of an electrostatic charge image developing toner with a toner particle composition that includes a binder resin, a release agent, and an inorganic mineral, where 80% or more of the release agent and inorganic mineral are present within 400 nm from the surface, enhancing the toner's surface strength and preventing abrasion and subsequent image deletion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the release agent is present on the surface of the toner particle to ensure peeling properties, then the image can be properly transferred and peeled from the fixing member, but the release agent is exposed due to abrasion during stirring in the developing unit, leading to toner solidification and image deletion

Engineering Contradiction:

Improvepeeling propertiesVSAvoidimage deletion

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The release agent is nested within the toner particle structure, specifically positioned in the inner layer rather than exposed on the outer surface. This nested configuration allows the release agent to maintain its function for peeling while being protected from abrasion during the stirring process in the developing unit, preventing both image deletion and solidification issues

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The toner particle is designed with non-uniform distribution of components: the release agent is concentrated in the inner layer while the outer layer has different composition characteristics. This local quality differentiation ensures that the release agent performs its peeling function when needed while being shielded from mechanical wear during normal operation

Inventive Principle:

Principle #3Local quality

2Productivity

If the toner is stirred in the developing unit to enable image formation, then the toner can be supplied to the photoreceptor, but abrasion during stirring exposes the release agent on the surface, causing toner solidification

Engineering Contradiction:

Improveimage formation capabilityVSAvoidtoner particle integrity

Core Design Contradiction:

ProductivityVSStability of the object's composition

Solution Approach 1:

The release agent is nested within the toner particle structure, specifically positioned in the inner layer rather than exposed on the outer surface. This nested configuration allows the release agent to maintain its function for peeling while being protected from abrasion during the stirring process in the developing unit, preventing both image deletion and solidification issues

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The release agent is pre-positioned within the inner layer of the toner particle before the stirring process begins. This preliminary positioning ensures that during the subsequent stirring and image formation process, the release agent remains protected and does not get exposed or cause solidification, maintaining toner particle integrity throughout operation

Inventive Principle:

Principle #10Preliminary action

3Productivity

If high temperature and high humidity conditions occur during image formation, then the developing process can proceed, but the exposed release agent accelerates toner solidification and image deletion

Engineering Contradiction:

Improveimage formation capabilityVSAvoidimage quality

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The release agent is nested within the toner particle structure, specifically positioned in the inner layer rather than exposed on the outer surface. This nested configuration allows the release agent to maintain its function for peeling while being protected from abrasion during the stirring process in the developing unit, preventing both image deletion and solidification issues

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The toner particle structure is designed with the release agent nested in the inner layer as a protective configuration before environmental challenges occur. This beforehand arrangement cushions against the harmful effects of high temperature and humidity by preventing release agent exposure, thereby maintaining image quality and preventing solidification even under challenging environmental conditions

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

Data Source

PatentUS9529288B1Electrostatic charge image developing toner, electrostatic charge image developer, and toner cartridge

Publication Date: 2016.12.27 FUJIFILM BUSINESS INNOVATION CORP

AI summary

An electrostatic charge image developing toner includes a toner particle containing a binder resin, a release agent, and an inorganic mineral, wherein 80% or more of the entire release agent is present in a portion within 400 nm from the surface of the toner particle and 80% or more of the entire inorganic mineral is present in a portion within 400 nm from the surface of the toner particle.