Polyimide Precursor Composition Low-Temperature Curing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing polyimide precursor solutions face challenges in achieving high concentration with low viscosity, stable imidization at low temperatures, and maintaining physical properties such as adhesiveness and chemical resistance, particularly when used in flexible substrates and printed wiring boards.
Innovation Solution
A polyimide precursor composition comprising an imidized tetracarboxylic acid and a diamine, specifically formulated to have a low viscosity even at high concentrations, allowing for the production of a polyimide coating film with high strength and excellent physical properties, which can be cured at temperatures of 250°C or lower.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If a polyamic acid solution or polyimide resin solution is used, then the solution can be formed into a coating film, but the high molecular weight and low solubility make it impossible to adjust the concentration to be high, requiring volatilization of a large amount of solvent and resulting in low productivity
Solution Approach 1:
The invention changes the molecular weight parameter of the polyimide precursor from high to low, enabling high concentration solutions with low viscosity. This parameter change allows the solute concentration to be adjusted to high levels (solving the concentration problem) while maintaining low viscosity for easy coating and reduced solvent volatilization (solving the productivity problem).
Solution Approach 2:
The invention performs preliminary imidization of the tetracarboxylic acid component before mixing with the diamine component. This preliminary action creates a precursor composition that can be dissolved at high concentrations with low viscosity, eliminating the need for high-temperature imidization later and enabling high productivity through reduced solvent volatilization.
2Temperature
If a polyimide resin precursor solution is used, then a coating film can be formed, but imidization must be performed at a heating temperature higher than 300°C, causing degradation of wiring materials on flexible substrates
Solution Approach 1:
The invention performs preliminary imidization of the tetracarboxylic acid component before use. This preliminary action transforms the acid component into an imidized form that reacts with diamine at low temperatures (250°C or lower), preventing wiring material degradation while still achieving complete imidization in the final coating film.
Solution Approach 2:
The invention segments the imidization process into two stages: (1) preliminary imidization of the tetracarboxylic acid component, and (2) final imidization during coating film formation. This segmentation allows the first stage to occur under controlled conditions that protect sensitive wiring materials, while the second stage completes the polyimide formation at safe temperatures.
3Quantity of substance
If a polyimide precursor solution with high concentration is prepared, then the solute concentration can be increased, but the viscosity of the solution increases significantly, affecting processability
Solution Approach 1:
The invention changes the molecular weight parameter of the polyimide precursor to low values, which fundamentally alters the viscosity-concentration relationship. This parameter change enables high solute concentration (improving feature) while maintaining low viscosity (preventing worsening of composition stability), thereby resolving the contradiction between concentration and viscosity.
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 enables the production of polyimide coating films with enhanced adhesiveness, environmental resistance, and chemical resistance, suitable for use in flexible substrates and printed wiring boards, while maintaining low imidization temperatures and stable viscosity over time.
Implementation Method 1
it is necessary to perform imidization, and the imidization must be performed at a heating temperature higher than 300° C. Therefore, for example, when such a polyimide resin precursor solution is used as a protective agent of a flexible substrate or the like, an adhesive of a formed body, or the like, a problem that a wiring material cannot withstand high temperatures
Implementation Method 2
A polyimide precursor composition comprising an imidized tetracarboxylic acid and a diamine, specifically formulated to have a low viscosity even at high concentrations, allowing for the production of a polyimide coating film with high strength and excellent physical properties, which can be cured at temperatures of 250°C or lower
Implementation Method 3
The solution enables the production of polyimide coating films with enhanced adhesiveness, environmental resistance, and chemical resistance
Data Source
AI summary
An object of the present invention is to provide a polyimide precursor composition that can be cured at low temperatures (250° C. or lower), while having a low viscosity even at a high concentration, and a method of producing the same. Another object of the present invention is to provide a polyimide coating film obtained from the polyimide precursor composition and having good physical properties, and a method of producing the same. Furthermore, another object of the present invention is to provide a photosensitive resin composition containing the polyimide precursor composition, and a method of producing the same. These objects can be achieved by the polyimide precursor composition containing an imidized tetracarboxylic acid having a specific structure and a diamine having a specific structure.