Electrophotographic Blade Polyurethane Resin Curing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing manufacturing processes for electrophotographic blades face challenges with long curing times, resulting in inefficient production and surface defects such as concave patterns due to non-uniform shrinkage, and the use of high catalyst quantities leads to poor flowability and contamination issues.
Innovation Solution
A polyurethane resin composition is developed, including a polyisocyanate, a polyol with a number average molecular weight of 2,000 to 4,000, a chain extender with a molecular weight of 200 or less, and a urethane curing catalyst, specifically using an isocyanurating or allophanating catalyst to achieve rapid curing while maintaining flowability and preventing surface defects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If the quantity of catalyst is enlarged to shorten curing time, then the curing reaction proceeds faster, but the liquid material becomes highly viscous and loses flowability
Solution Approach 1:
The patent changes the chemical parameters of the catalyst system by introducing a specific isocyanurating catalyst (triisobenzylideneaminetriphenol) with controlled activity. This catalyst provides moderate curing speed that maintains liquid flowability during molding while still achieving practical curing times, resolving the contradiction between fast curing and good flowability.
2Ease of manufacture
If a highly temperature-sensitive isocyanurating catalyst is used to improve flowability, then the liquid material spreads well in the mold, but the reaction proceeds rapidly at stated temperature causing non-uniform shrinkage and surface patterns
Solution Approach 1:
The patent modifies the catalyst parameters by selecting an isocyanurating catalyst with optimal temperature sensitivity and activity. The specific catalyst (triisobenzylideneaminetriphenol) provides balanced reactivity that ensures uniform reaction progression, preventing non-uniform shrinkage and surface patterns while maintaining good flowability during the molding process.
3Ease of manufacture
If the curing time is long, then the manufacturing process is simple, but the production efficiency is low and requires numerous molds
Solution Approach 1:
The patent optimizes the catalyst parameters to achieve moderate curing time that balances manufacturing simplicity with production efficiency. The selected isocyanurating catalyst enables curing within a practical time frame, reducing the number of molds needed while keeping the manufacturing process straightforward and maintainable.
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 solution results in a blade with improved flowability, reduced curing time, and absence of concave patterns, enhancing the quality and production efficiency of electrophotographic blades.
Implementation Method 1
The polyurethane resin is produced by a prepolymer method, a semi-one-shot method or a one-shot method, using a polyisocyanate, a polyol, a chain extender and a catalyst
Implementation Method 2
a highly temperature-sensitive isocyanurating catalyst is often used which little shows its activity until the liquid temperature reaches a stated temperature, and makes the curing reaction proceed rapidly after the liquid temperature has become higher than the stated temperature
Data Source
AI summary
A blade for electrophotographic apparatus which has a blade member formed of a polyurethane resin, wherein the polyurethane resin is a resin produced by using a polyurethane raw-material composition containing at least the following components (A) to (E): (A) a polyisocyanate; (B) a polyol having a number average molecular weight of 2,000 or more and 4,000 or less; (C) a chain extender having a molecular weight of 200 or less: (D) a polyol having a number average molecular weight which is smaller than the number average molecular weight of the component-(B) polyol and is larger than the molecular weight of the component-(C) chain extender; and (E) a urethane curing catalyst.