Capsule Color Toner for Low-Temperature Fixing and Heat Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electrophotographic toners face challenges in achieving compatibility between heat-resistant storage stability and low-temperature fixability, with issues such as resin limitations, particle shape, and surface layer peeling leading to reduced image quality and durability.
Innovation Solution
A color toner with capsule-type toner particles featuring a surface layer formed of a specific resin (b) on a toner base particle (A), where the loss modulus characteristics are optimized to ensure low-temperature fixability and heat-resistant storage stability, with a temperature range and viscoelasticity ratio that allows for sharp melt properties and improved durability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a pulverization method is used to produce toner, then low-temperature fixability is improved, but the number of resin alternatives is limited and production complexity increases
Solution Approach 1:
The toner particle is divided into two distinct parts: a core particle containing binder resin, colorant, and wax, and a surface layer made of resin. This segmentation allows each part to have optimized properties for its specific function, resolving the contradiction between low-temperature fixability and production simplicity.
Solution Approach 2:
The toner uses a composite structure combining different materials with complementary properties: the core contains binder resin for aggregation, colorant for color, and wax for low-temperature fixability, while the surface layer provides heat-resistant storage stability. This composite approach enables simultaneous achievement of multiple performance requirements.
2Manufacturing precision
If particle size distribution is sharpened for high developing performance, then developing performance is improved, but production yield reduces or production steps increase
Solution Approach 1:
The invention changes the fundamental parameter of particle structure from uniform composition to differentiated core-shell structure. This allows the use of conventional, simpler production methods while achieving the desired particle size distribution and performance characteristics without sacrificing yield.
3Measurement precision
If toner particles are pulverized to reduce particle diameter, then resolution is improved, but surface layer peeling occurs and fine powder is generated
Solution Approach 1:
The surface layer is designed as a continuous outer shell that completely covers the core particle, creating a protective capsule structure. This spherical shell prevents surface layer peeling and fine powder generation during pulverization, while allowing the core to maintain its functional properties for high resolution.
4Shape
If conventional polymerization methods are used to prepare spherical toner, then spherical particles are obtained, but binder resin is limited to vinyl resin only
Solution Approach 1:
The invention extracts the essential function of the surface layer (providing spherical shape and protective properties) from the conventional polymerization process. This allows the use of polyester resin in the core while forming a separate resin surface layer, greatly expanding resin selection flexibility beyond vinyl resin limitations.
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 achieves excellent low-temperature fixability and heat-resistant storage stability, enhancing image quality and durability by leveraging the distinct melt characteristics of the toner base and surface layers, thereby addressing the compatibility issues in existing toners.
Implementation Method 1
a temperature Tp at which a curve (1) obtained by plotting a temperature (°C.) on an axis of abscissa and a common logarithm (log G'') of a value obtained by dividing a loss modulus G'' (Pa) of the color toner by a unit (Pa) of the loss modulus on an axis of ordinate shows a maximum is present, and Tp satisfies a relationship of 40° C.≦Tp≦60° C.
Implementation Method 2
the sharp melt property of the binder resin of toner is improved so that an image formed with the toner can be fixed at an additionally low temperature
Data Source
AI summary
The color toner has capsule type toner particles each having a surface layer (B) mainly formed of a resin (b) on the surface of a toner base particle (A) containing at least a binder resin (a), a colorant, and a wax, in which (1) a temperature Tp at which a curve 1 obtained by plotting a temperature on an axis of abscissa and the common logarithm of a value obtained by dividing the loss modulus G″ of the color toner by the unit of the loss modulus on an axis of ordinate shows a maximum is present, and Tp satisfies the relationship of 40° C.≦Tp≦60° C., (2) a temperature Ts at which a curve 2 obtained by differentiating the curve 1 with respect to the temperature twice shows a local minimum is present in the temperature range of Tp+10(° C.) to Tp+40(° C.), and (3) a ratio G″(Ts)/G″(Ts+5) in the curve 1 is larger than 3.0.