Toner with Segmented Glass Transition for Fixability and Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional toners face challenges in achieving both low-temperature fixability and heat-resistant storage stability, with traditional production methods resulting in poor particle size distribution, amorphous shape, and increased energy consumption, as well as issues with cleanability and transferability.
Innovation Solution
A toner composition featuring toner base particles with a binder resin and resin particles on their surface, with specific glass transition temperature ranges and circularity values, enhancing low-temperature fixability, heat-resistant storage stability, cleanability, and transferability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a low-melting-point material is used to improve low-temperature fixability, then the toner can be fixed at lower temperatures, but the heat-resistant storage stability deteriorates
Solution Approach 1:
The toner is divided into two distinct components: toner base particles containing binder resin, and separate resin particles on the surface. This segmentation allows each component to have optimized properties - the binder resin provides structural integrity for storage stability, while the surface resin particles control fixation temperature, thereby resolving the contradiction between low-temperature fixability and heat-resistant storage stability
Solution Approach 2:
The toner employs a composite structure combining binder resin and surface resin particles with different glass transition temperatures. The binder resin (Tg: 20-50°C) ensures heat-resistant storage stability, while the surface resin particles (Tg: -40-10°C) enable low-temperature fixability. This composite material approach allows simultaneous achievement of both opposing requirements
2Ease of manufacture
If the kneading and pulverizing method is used to produce toner, then the production process is simple, but the particle size distribution becomes broad and the shape becomes amorphous, reducing image quality
Solution Approach 1:
The production process is segmented into two independent stages: first forming toner base particles with controlled size and shape, then separately forming resin particles and coating them on the base particles. This segmentation enables precise control of particle size distribution and spherical shape while maintaining production feasibility, resolving the contradiction between manufacturing simplicity and manufacturing precision
3Temperature
If wax is added during toner production to improve fixability, then the release effect is enhanced, but the toner cracks during pulverization and adheres to carrier and photoconductor
Solution Approach 1:
The harmful wax component is completely extracted and replaced with resin particles having controlled glass transition temperature. The resin particles provide the necessary release effect for fixability without causing cracking or adhesion problems, thereby resolving the contradiction between improvement in fixability and elimination of harmful effects
Solution Approach 2:
The key parameter changed is the glass transition temperature of the surface coating material. By using resin particles with Tg of -40-10°C instead of wax, the material provides adequate release effect at fixation temperature while maintaining structural integrity during pulverization, preventing cracking and adhesion to carrier and photoconductor
4Ease of operation
If the toner shape is made amorphous to improve cleanability, then the toner is prevented from passing through cleaning member, but the transferability deteriorates
Solution Approach 1:
Different parts of the toner structure are assigned different properties: the core toner base particles have spherical shape for excellent transferability, while the surface resin particles provide controlled circularity (0.970-0.985) for cleanability. This local differentiation of properties resolves the contradiction between cleanability and transferability
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 improved low-temperature fixability, heat-resistant storage stability, and cleanability due to its tailored glass transition temperatures and circularity, leading to better image quality and reduced energy consumption.
Implementation Method 1
A glass transition temperature of the toner at the first heating in differential scanning calorimetry (DSC) is 20° C. or higher and 50° C. or lower. A glass transition temperature of a tetrahydrofuran (THF)-insoluble component of the toner at the first heating in differential scanning calorimetry (DSC) is −40° C. or higher and 10° C. or lower.
Data Source
AI summary
A toner includes: toner base particles each containing a binder resin; and resin particles on a surface of each of the toner base particles. A glass transition temperature (Tg) of the toner at the first heating in differential scanning calorimetry (DSC) is 20° C. or higher and 50° C. or lower. A glass transition temperature of a tetrahydrofuran (THF)-insoluble component of the toner at the first heating in DSC is −40° C. or higher and 10° C. or lower. An average circularity of the toner is 0.970 or more and 0.985 or less. A standard deviation of the average circularity is 0.020 or less.