PTFE–Thermoplastic PCB Composites for Low-Loss, Strong Bonding

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current printed circuit boards (PCBs) face issues with high dielectric loss tangents, poor post-processing ability, and inadequate bonding properties, particularly in FR4 and PTFE-based composites.

Innovation Solution

A composite comprising thermoplastic polymers, such as cyclic olefin copolymers and PTFE-based polymers, with optional reinforcing materials like silica, alumina, and inorganic powders, is developed to achieve low dielectric loss tangents and improved mechanical and bonding properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If FR4 composites are used for PCB applications, then mechanical strength and structural stability are achieved, but dielectric loss tangent increases beyond acceptable levels for high-frequency applications

Engineering Contradiction:

Improvedielectric loss tangentVSAvoidhigh dielectric loss

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent employs composite materials by combining PTFE base polymer with thermoplastic fluoropolymer particles (20-80 wt%) to create a hybrid composite that leverages the low dielectric loss of PTFE while incorporating the processing advantages and bonding properties of thermoplastics. This composite structure resolves the contradiction by achieving dielectric loss tangent <10^-3 while maintaining mechanical integrity.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent changes the chemical composition parameters of the dielectric material by selecting specific thermoplastic fluoropolymers (FEP, PFA, ECTFE, PVDF) with controlled particle sizes (1-100 micrometers) and optimization ratios (20-80 wt%), transforming the material properties to achieve ultra-low dielectric loss while maintaining processability and bonding capabilities.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If PTFE-based composites are used for PCB applications, then dielectric loss is reduced, but post-processing ability and bonding properties deteriorate

Engineering Contradiction:

Improvedielectric loss tangentVSAvoidpost-processing ability

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent creates a composite material system where thermoplastic fluoropolymer particles are dispersed in the PTFE matrix, combining the low dielectric loss of PTFE with the superior processability and bonding characteristics of thermoplastics. The composite enables both low dielectric loss and good post-processing ability through synergistic material combination.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent applies local quality by distributing thermoplastic fluoropolymer particles throughout the PTFE matrix, creating regions with enhanced bonding capability and processability while maintaining the overall low dielectric loss property of the PTFE base material. This localized enhancement resolves the contradiction between dielectric performance and manufacturability.

Inventive Principle:

Principle #3Local quality

3Reliability

If PTFE-based composites are used for PCB applications, then dielectric loss is reduced, but bonding properties to copper foil cladding become inadequate

Engineering Contradiction:

Improvedielectric loss tangentVSAvoidbonding strength

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The patent develops a composite where thermoplastic fluoropolymer particles (20-80 wt%) are incorporated into the PTFE matrix, providing bonding sites that enhance adhesion to copper foil cladding while the PTFE continuous phase maintains low dielectric loss. The composite structure enables simultaneous achievement of low dielectric loss and adequate bonding strength.

Inventive Principle:

Principle #40Composite materials

4Ease of manufacture

If higher ratios of thermoplastic polymer are added to improve bonding and processing, then post-processing ability and bonding properties improve, but dielectric loss tangent increases

Engineering Contradiction:

Improvebonding propertiesVSAvoiddielectric loss tangent

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The patent optimizes the concentration parameter of thermoplastic fluoropolymer particles within the specific range of 20-80 wt%, balancing the competing requirements of bonding strength and dielectric performance. This parameter optimization resolves the contradiction by identifying the optimal composition window where both bonding properties and low dielectric loss are achieved simultaneously.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS12356544B2Composites for high-frequency printed circuit boards and methods of making

Publication Date: 2025.07.08 CORNING INC

AI summary

A composite includes at least one thermoplastic polymer; and at least one PTFE-based polymer, such that the composite has a dielectric loss tangent of less than 10−3. Moreover, a method for preparing a composite includes mixing at least one thermoplastic polymer with at least one PTFE-based polymer to form a homogenous mixture; melting the mixture to form a composite material; and hot pressing the composite material to form a composite sheet.