Polyester Resin Toner Hot-Offset Resistance VOC Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing polyester resin for toner faces challenges with high viscosity during polymerization, difficulty in removal from polymerization devices, and high volatile organic compound (VOC) levels, which affect hot-offset resistance and productivity.
Innovation Solution
A polyester resin formulation incorporating a constitutional unit derived from tetravalent carboxylic acids and aliphatic alcohols with specific molecular structures, optimized to achieve low VOC levels and improved storage elastic modulus, allowing for easier removal and enhanced hot-offset resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a large amount of tri- or higher valent polyfunctional monomer is used to improve elasticity at high temperature, then hot-offset resistance is improved, but viscosity increases remarkably causing resin to solidify in polymerization device
Solution Approach 1:
The patent changes the chemical structure parameters of the carboxylic acid component by specifying particular compounds (1,2,4-naphthalenetricarboxylic acid and its derivatives) with controlled molecular weight and structural characteristics. This parameter optimization allows achieving the required crosslinking density for elasticity while maintaining lower viscosity during polymerization, enabling easy removal from the polymerization device.
2Reliability
If polyfunctional monomer is used to form crosslinked structure for high elasticity, then hot-offset resistance improves, but resin solidifies due to increased viscosity
Solution Approach 1:
The patent optimizes the molecular weight parameters of the polyfunctional monomer within specific ranges (number average molecular weight 200-5000) and controls the content of carboxylic acid units with 3 or more functional groups at 5-50 mol%. These parameter changes enable forming adequate crosslinked structures for hot-offset resistance while preventing excessive viscosity increase that would hinder polymerization productivity.
Solution Approach 2:
The patent creates a composite resin system combining polyester resin with polyfunctional monomers of specifically controlled molecular weight and structure. This composite approach allows the system to achieve the desired crosslinking for reliability while the controlled molecular weight components prevent excessive viscosity, maintaining productivity during polymerization.
3Ease of manufacture
If conventional polyester resin is used, then processing is straightforward, but VOC emissions are high affecting health and environment
Solution Approach 1:
The patent changes the chemical composition parameters by incorporating specific polyfunctional monomers (1,2,4-naphthalenetricarboxylic acid and its derivatives) that have lower volatility compared to conventional monomers. This parameter change reduces VOC emissions while the controlled molecular weight and structural features maintain ease of processing during manufacturing.
Data Source
AI summary
A polyester resin, including:(a) a constitutional unit derived from at least one tetravalent carboxylic acid selected from Compounds (A) and (B);a constitutional unit derived from a bisphenol A-alkylene oxide adduct; anda constitutional unit derived from an aliphatic alcohol having a boiling point of lower than or equal to 290° C.,where the polyester resin is free of a constitutional unit derived from a monovalent carboxylic acid, an acid value of the polyester resin is 8 to 55 mg KOH/g, and an amount of the tetravalent carboxylic acid is 1 to 30 mol % when an total amount of the tetravalent carboxylic acid, and other polyvalent carboxylic acid excluding the Compounds (A) and (B) is set to 100 mol %,where X1, X2, X3 and X4 each independently represent a trivalent organic group, and Z1 and Z2 each independently represent a single bond or a divalent organic group, wherein tetravalent carboxylic acid is, for example, 3,3′,4,4′-biphenyltetracarboxylic dianhydride, 2,2′,6,6′-biphenyltetracarboxylic dianhydride, 4,4′-oxydiphthalic dianhydride, 9,9-bis(3,4-dicarboxyphenyl) fluorene dianhydride, and/or 4,4′-(4,4′-isopropylidenediphenoxy) diphthalic anhydride.