Polyarylate Laminate for High-Frequency Circuit Boards

Solution Overview

Problem

Existing high-frequency circuit board laminates struggle to achieve a balance between low dielectric characteristics, low water absorption, and adhesiveness between the polymer layer and the copper layer.

Innovation Solution

A laminate comprising a copper layer and a polymer layer, where the polymer layer contains a specific polyarylate with repeating units represented by Formulas (I-A), (I-B), and (I-C), and a repeating unit II, which enhances the laminate's dielectric properties, water resistance, and adhesiveness.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a polymer layer is used in high-frequency circuit board laminates, then low dielectric characteristics are improved, but adhesiveness to the copper layer deteriorates

Engineering Contradiction:

Improvelow dielectric characteristicsVSAvoidadhesiveness between polymer layer and copper layer

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The polymer layer is designed with non-uniform composition by incorporating specific repeating units (I-A, I-B, or I-C) at controlled ratios. This creates local variations in chemical structure that simultaneously provide low dielectric properties in signal transmission regions and enhanced adhesiveness at the copper interface, resolving the contradiction between dielectric performance and bonding strength.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The invention uses a composite polymer structure combining multiple repeating units (I and II) with specific molecular architectures. This composite approach allows the material to exhibit both low dielectric characteristics for high-frequency performance and improved copper adhesion, achieving properties that neither simple polymer could provide alone.

Inventive Principle:

Principle #40Composite materials

2Reliability

If a polymer layer is used in high-frequency circuit board laminates, then low dielectric characteristics are improved, but water absorption increases

Engineering Contradiction:

Improvelow dielectric characteristicsVSAvoidwater absorption

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The polymer layer is designed with non-uniform composition by incorporating specific repeating units (I-A, I-B, or I-C) at controlled ratios. This creates local variations in chemical structure that simultaneously provide low dielectric properties in signal transmission regions and enhanced adhesiveness at the copper interface, resolving the contradiction between dielectric performance and bonding strength.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The invention uses a composite polymer structure combining multiple repeating units (I and II) with specific molecular architectures. This composite approach allows the material to exhibit both low dielectric characteristics for high-frequency performance and improved copper adhesion, achieving properties that neither simple polymer could provide alone.

Inventive Principle:

Principle #40Composite materials

Data Source

PatentUS20250187308A1laminate

Publication Date: 2025.06.12 FUJIFILM CORP

AI summary

An object of the present invention is to provide a laminate having excellent low dielectric characteristics, low water absorption, and adhesiveness. The laminate of the present invention includes a copper layer and a polymer layer, in which the polymer layer contains a polyarylate, and the polyarylate has at least one repeating unit I selected from the group consisting of a repeating unit represented by Formula (I-A), a repeating unit represented by Formula (I-B), and a repeating unit represented by Formula (I-C), and has a repeating unit II represented by Formula (II).