Signal Cable Insulation Roughness for Plating Adhesion

Solution Overview

Problem

Conventional signal transmission cables experience a gap between the insulation layer and the external conductor, which reduces the shielding effect and increases transmission loss.

Innovation Solution

A signal transmission cable with an insulation layer having an arithmetic average roughness of 0.6 μm to 10 μm, enhanced through dry-ice-blasting and corona discharge exposure, to improve adhesion with the plating layer, reducing gaps and enhancing shielding.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If the insulation layer surface is made smooth, then transmission loss is reduced, but adhesion between insulation layer and plating layer deteriorates causing gaps

Engineering Contradiction:

Improvetransmission lossVSAvoidadhesion between layers

Core Design Contradiction:

Loss of energyVSReliability

Solution Approach 1:

The patent applies different surface qualities to different regions of the insulation layer. The outer peripheral surface is roughened with a controlled arithmetic average roughness of 0.03 μm or more to enhance adhesion with the plating layer, while the inner surface remains smooth to maintain low transmission loss. This local differentiation resolves the contradiction between adhesion and transmission loss.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent changes the surface roughness parameter of the insulation layer's outer peripheral surface to a specific range (arithmetic average roughness of 0.03 μm or more) to optimize adhesion. This parameter modification allows the plating layer to form a continuous coating without gaps, improving reliability without significantly increasing transmission loss.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If the insulation layer surface is roughened to improve adhesion, then gap formation is reduced, but transmission loss increases

Engineering Contradiction:

Improveadhesion between layersVSAvoidtransmission loss

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

The patent applies different surface qualities to different regions of the insulation layer. The outer peripheral surface is roughened with a controlled arithmetic average roughness of 0.03 μm or more to enhance adhesion with the plating layer, while the inner surface remains smooth to maintain low transmission loss. This local differentiation resolves the contradiction between adhesion and transmission loss.

Inventive Principle:

Principle #3Local quality

3Object-affected harmful factors

If a plating layer is applied to cover the insulation layer, then shielding effect is improved, but gap formation between layers occurs reducing effectiveness

Engineering Contradiction:

Improveshielding effectVSAvoidcontinuity of plating layer

Core Design Contradiction:

Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent applies a preliminary surface treatment to the insulation layer's outer peripheral surface before applying the plating layer. The surface is roughened to create anchoring sites that ensure the plating layer adheres continuously without gaps. This preliminary action guarantees the reliability and continuity of the plating layer, maximizing the shielding effect.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent applies different surface qualities to different regions of the insulation layer. The outer peripheral surface is roughened with a controlled arithmetic average roughness of 0.03 μm or more to enhance adhesion with the plating layer, while the inner surface remains smooth to maintain low transmission loss. This local differentiation resolves the contradiction between adhesion and transmission loss.

Inventive Principle:

Principle #3Local quality

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 achieves high adhesion between the insulation and plating layers, thereby improving the shielding effect and reducing transmission loss in signal transmission cables.

Implementation Method 1

applying a dry-ice-blasting to an outer peripheral surface of the insulation layer

Methodology Applied

Scientific EffectDry-ice-blasting: Abrasion

Implementation Method 2

applying a corona discharge exposure process to the outer peripheral surface

Methodology Applied

Scientific EffectCorona discharge: Corona Discharge

Data Source

PatentUS10930988B2Resin with plating layer and method of manufacturing the same

Publication Date: 2021.02.23 PROTERIAL LTD

AI summary

A signal transmission cable includes a signal line, an insulation layer configured to cover the signal line, and a plating layer configured to cover the insulation layer. An arithmetic average roughness Ra of an outer peripheral surface of the insulation layer is between 0.6 μm and 10 μm inclusive. A method of manufacturing the signal transmission cable includes covering the signal line with the insulation layer, followed by conducting a dry-ice-blasting on the outer peripheral surface of the insulation layer, followed by conducting a corona discharge exposure process on the outer peripheral surface, and forming the plating layer on the outer peripheral surface.