Polyester Resin Toner Anti-Hydrolysis Agent
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Polyester resins with low softening points, used as binder resins in toner production, suffer from high acid values and low hydroxyl radical values, leading to poor moisture resistance, chargeability, and image stability due to hydrolysis, which affects durability and long-term storage of toners.
Innovation Solution
A polyester resin is developed with controlled acid and hydroxyl radical values by using alkylesters of aromatic and aliphatic dibasic acids, aromatic and aliphatic diols, and an anti-hydrolysis agent to prevent hydrogen bonding with water, thereby enhancing hydrolysis resistance and moisture resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If polyester resin with low softening point is used to improve low-temperature fixability, then fixability is improved, but acid value increases and moisture resistance deteriorates
Solution Approach 1:
The patent applies parameter changes by precisely controlling the acid value (0.1-2.0 mgKOH/g) and hydroxyl radical value (200-600 mgKOH/g) of the polyester resin through optimized polycondensation reaction conditions, including temperature control (200-240°C), pressure control (0.1-10 mmHg), and reaction time control, thereby achieving both low softening point and high moisture resistance
Solution Approach 2:
The patent uses composite materials by combining polyester resin with specific additives including charge control agents (0.1-5 wt%), colorants (0.1-5 wt%), and waxes (5-30 wt%), creating a composite toner formulation where each component contributes to overall performance, allowing the binder resin to have low softening point while the composite system maintains moisture resistance
2Temperature
If polyester resin with low molecular weight is used to achieve low softening point, then softening point is reduced, but degree of polymerization decreases and chargeability deteriorates
Solution Approach 1:
The patent applies parameter changes by optimizing the molecular weight and degree of polymerization of the polyester resin through controlled polycondensation reaction parameters (temperature 200-240°C, pressure 0.1-10 mmHg, catalyst selection), achieving a balance where the resin has sufficiently low softening point for fixability while maintaining adequate molecular weight for chargeability
Solution Approach 2:
The patent uses charge control agents that replicate or enhance the charge properties of the binder resin, with charge control agents having specific glass transition temperatures (0-100°C) and charge characteristics that complement the polyester resin, thereby maintaining image formation performance even with lower molecular weight resin
3Reliability
If glass transition temperature is increased to improve blocking resistance, then blocking resistance is improved, but low-temperature fixability and pulverizability deteriorate
Solution Approach 1:
The patent applies parameter changes by carefully selecting and controlling the glass transition temperature of the binder resin (50-100°C) through monomer selection (aromatic diols, aliphatic diols, cyclic carbonates) and composition ratios, achieving optimal balance between blocking resistance and fixability
Solution Approach 2:
The patent applies local quality by using a mixture of different diol components (aromatic diols, aliphatic diols, cyclic carbonates) with different glass transition temperatures and properties, where each component contributes differently to the overall resin characteristics, allowing localized optimization of blocking resistance while maintaining overall fixability
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 resulting polyester resin exhibits improved hydrolysis resistance, low-temperature fixability, and image stability, ensuring better toner durability and storage stability with optimized acid and hydroxyl radical values.
Implementation Method 1
hydrolysis by hydrogen bonding between ester linkages in the chain of the polyester resin and/or carboxyl terminals of the resin and water
Implementation Method 2
preventing hydrolysis of the resin with addition of anti-hydrolysis agent thereto
Data Source
AI summary
The present invention relates to a polyester resin prepared by adding an anti-hydrolysis agent to a reactant comprising an acid selected from an alkylester of aromatic dibasic acid or a mixture of an alkylester of aromatic dibasic acid and an alkylester of aliphatic dibasic acid, an aromatic diol and an aliphatic diol; and a toner produced by using the same as a binder resin.