Halogen-Free Resin Composition for Printed Circuit Boards
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional halogen-based flame retardants in laminates for printed circuit boards pose environmental concerns and fail to meet the demands for low dielectric constant, low dielectric loss, high thermal resistance, and low water absorption required for high-frequency and high-speed electronic applications.
Innovation Solution
A halogen-free resin composition combining alkyl phenol epoxy resin, benzoxazine resin, and alkyl phenol novolac curing agent, with the addition of a phosphorus-containing flame retardant, which synergistically enhances dielectric properties, thermal resistance, and flame retardancy while reducing water absorption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If brominated flame retardants are used to achieve flame retardancy, then flame retardancy is improved, but environmental harm and health risks worsen
Solution Approach 1:
The patent changes the chemical composition parameters by replacing brominated flame retardants with phosphorus-containing flame retardants and specific epoxy resin combinations, maintaining flame retardancy while eliminating harmful environmental effects
Solution Approach 2:
The patent uses a composite resin system combining phenolic resin, epoxy resin, and phosphorus-containing flame retardant to achieve both flame retardancy and environmental safety, creating a multi-component material system that addresses both requirements
2Ease of operation
If dicyandiamide is used as a curing agent for good processing operability, then ease of operation is improved, but thermal resistance worsens
Solution Approach 1:
The patent changes the curing agent from dicyandiamide to phenolic resin, which fundamentally alters the chemical structure and bonding characteristics to achieve both good processability and high thermal resistance simultaneously
Solution Approach 2:
Phenolic resin acts as an intermediary curing agent that bridges the gap between processing requirements and thermal performance, providing reactive groups for curing while forming thermally stable structures
3Temperature
If phenolic resin is used as a curing agent to improve thermal resistance, then thermal resistance is improved, but dielectric properties worsen
Solution Approach 1:
The patent creates a composite resin system combining phenolic resin with specific epoxy resins and phosphorus-containing flame retardants, where the synergistic interaction of components achieves both high thermal resistance and low dielectric constant
Solution Approach 2:
The patent optimizes the local chemical environment by selecting specific phosphorus-containing compounds and epoxy resin structures that locally reduce dielectric constant while maintaining the overall thermal stability provided by phenolic resin
4Object-affected harmful factors
If conventional halogen-free flame retardant laminates are used, then environmental safety is improved, but water absorption increases
Solution Approach 1:
The patent develops a composite resin system where phenolic resin, epoxy resin, and phosphorus-containing flame retardant work synergistically to create a dense cross-linked structure that provides both environmental safety and low water absorption
Solution Approach 2:
The patent changes the molecular structure parameters by selecting specific phosphorus-containing compounds and curing agents that form hydrophobic cross-linked networks, reducing water absorption while maintaining halogen-free composition
Data Source
AI summary
The present invention discloses a halogen-free resin composition, and a prepreg and a laminate used for printed circuit. The halogen-free resin composition comprises: alkyl phenol epoxy resin; benzoxazine resin; alkyl phenol novolac curing agent; phosphorus-containing flame retardant. The alkyl phenol epoxy resin used in the present invention has many alkyl branched chains in its molecular structure, making the composition have excellent dielectric properties while it has higher glass transition temperature, low water absorption and good heat resistance. Mixing benzoxazine resin into the composition can further reduce dielectric constant, dielectric loss value and water absorption of the cured product. With alkyl phenol novolac being used as curing agent, the advantages that the molecular structure thereof has many alkyls and thus the dielectric properties are excellent and the water absorption is low are fully played. A prepreg and a laminate used for printed circuit prepared using the resin composition have low dielectric constant, low dielectric loss factor, low water absorption, high dimensional stability, high thermal resistance and good flame retardancy, processability and chemical resistance.