Toner Binder Network Structure for Halftone Graininess
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current toners face challenges in achieving excellent low-temperature fixability and halftone image graininess, particularly in high-speed machines operating in high-temperature, high-humidity environments, where graininess worsens due to uneven toner melting and reduced flowability.
Innovation Solution
A toner with a specific binder material composition that forms a unified network structure by dispersing linear and crosslinked components at the molecular level, controlling their physical entanglement to maintain low-temperature fixability while improving halftone image graininess through controlled viscoelastic properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If the low-temperature fixability of a toner is improved by imparting sharp melt behavior, then the toner undergoes excessive liquefaction at protrusions on the paper surface, but this causes deterioration in the halftone image graininess
Solution Approach 1:
The invention changes the molecular structure parameters of the binder resin by introducing specific functional groups (carboxyl, hydroxyl, or amino groups) with controlled concentrations. This modifies the melt behavior and viscosity characteristics of the toner, enabling it to achieve appropriate melting at protrusions while maintaining flowability in depressions, thus resolving the graininess issue while preserving low-temperature fixability
Solution Approach 2:
The invention creates a composite binder resin system by combining base resin components with functionalized resin components containing specific polar groups. This composite structure allows the toner to exhibit both sharp melting characteristics for low-temperature fixing and controlled viscosity for uniform distribution, preventing excessive liquefaction and improving halftone image quality
2Productivity
If a sharp melt behavior is imparted to the toner to accommodate high-speed machines, then the low-temperature fixability is improved, but the toner undergoes excessive liquefaction at protrusions and halftone image graininess deteriorates
Solution Approach 1:
The invention modifies the viscosity-temperature relationship parameters of the toner by incorporating functional groups with specific concentrations. This allows the toner to maintain sharp melting for high-speed fixing while controlling the degree of liquefaction through adjusted molecular interactions, preventing excessive spreading at protrusions and maintaining image quality
3Reliability
If the toner is used in a high-temperature, high-humidity environment for long-term use, then the toner flowability declines due to frequent rubbing in the developing nip, but this causes deterioration in dot reproducibility and halftone image graininess
Solution Approach 1:
The invention changes the surface charge and flowability parameters of the toner by introducing functional groups that enhance electrostatic stability. This allows the toner to maintain consistent charging characteristics and flowability even after prolonged exposure to high-temperature, high-humidity conditions and frequent rubbing, preserving dot reproducibility and image quality over time
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 toner exhibits excellent low-temperature fixability and halftone image graininess across a broad range of media, even in long-term use in high-speed machines, by preventing excessive melting and maintaining flowability in high-temperature, high-humidity conditions.
Implementation Method 1
controlling their physical entanglement to maintain low-temperature fixability while improving halftone image graininess through controlled viscoelastic properties
Implementation Method 2
the toner preferably undergoes sharp melting within the fixing nip
Data Source
AI summary
A toner comprising a toner particle containing a resin and a colorant, wherein, with respect to a temperature-storage elastic modulus curve obtained by powder dynamic viscoelastic measurement on the toner, (I) the relative minimum values for the variation in the storage elastic modulus E′ with respect to temperature T in the temperature range of at least 30° C. and not more than 180° C. have a relative minimum value of equal to or less than −1.00×107 and the relative minimum value on the lowest temperature side is equal to or less than −1.00×108; (II) the storage elastic modulus E′ (50) of the toner at 50° C. is at least 1.00×109 and not more than 9.00×109; and (III) for a storage elastic modulus E′ (120) of the toner at 120° C., E′ (50) and E′ (120) satisfy 1.50≤[E′ (50)]/[E′ (120)]≤3.00.