Selective Gold Plating via Heterocyclic Additive

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional gold plating solutions often deposit gold on undesired areas, leading to inefficiencies and increased costs due to the need for masking and subsequent removal of unwanted gold deposits, and they lack stability during storage.

Innovation Solution

A gold plating solution incorporating a reaction product of a nitrogen-containing heterocyclic compound and epihalohydrin, along with gold cyanide and cobalt compounds, which enhances selective deposition and stability, allowing for restricted gold deposition on desired areas while maintaining corrosion resistance, wear resistance, and conductivity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of substance

If conventional gold plating solutions are used, then gold can be deposited on the substrate, but gold is also deposited on undesired areas leading to unnecessary metal consumption

Engineering Contradiction:
Improvegold consumptionVSAvoidselective deposition control
Core Design Contradiction:
Loss of substanceVSManufacturing precision

Solution Approach 1:

The patent introduces a specific additive (hexamethylene tetramine in combination with other compounds) as an intermediary substance that mediates between the gold plating solution and the substrate. This additive acts as a selective agent that prevents gold deposition on undesired areas while allowing deposition on targeted areas, thereby reducing unnecessary gold consumption without compromising manufacturing precision

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent modifies the chemical parameters of the plating solution by adding specific compounds (hexamethylene tetramine, fluorinated compounds, etc.) that change the deposition behavior of gold. These parameter changes enable selective deposition control, allowing gold to be deposited only on desired areas while preventing deposition on undesired areas, thus reducing material waste

Inventive Principle:
Principle #35Parameter changes

2Loss of substance

If masking is used to restrict gold deposition to desired areas, then gold consumption is reduced, but the process complexity and time increase

Engineering Contradiction:
Improvegold consumptionVSAvoidmasking process complexity
Core Design Contradiction:
Loss of substanceVSDevice complexity

Solution Approach 1:

The patent extracts the selective deposition function from the mechanical masking process and transfers it to the chemical composition of the plating solution itself. By incorporating selective additives directly into the solution, the need for complex masking operations is eliminated, while still achieving restricted gold deposition on desired areas only

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The plating solution is designed to be self-regulating through the inclusion of selective additives that automatically prevent deposition on undesired areas. The solution itself provides the selectivity function without requiring external masking devices or complex process controls, thereby simplifying the overall manufacturing process

Inventive Principle:
Principle #25Self-service

3Manufacturing precision

If hexamethylene tetramine is added to hard gold plating solution to suppress unnecessary precipitation, then selective deposition is improved, but the plating solution becomes unstable

Engineering Contradiction:
Improveselective depositionVSAvoidplating solution stability
Core Design Contradiction:
Manufacturing precisionVSStability of the object's composition

Solution Approach 1:

The patent creates a composite plating solution system by combining hexamethylene tetramine with other stabilizing compounds (such as fluorinated compounds and other additives). This composite formulation maintains the selective deposition capability of hexamethylene tetramine while the additional compounds provide stability to the solution, preventing decomposition and maintaining consistent performance over time

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent incorporates stabilizing additives in advance into the plating solution formulation to cushion against the instability caused by hexamethylene tetramine. These pre-added stabilizers prevent potential decomposition or unwanted reactions before they occur, ensuring the solution remains stable during storage and use while maintaining its selective deposition properties

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

4Loss of substance

If plating is conducted with masking to restrict gold usage, then gold consumption is reduced, but removal of gold from masked areas requires additional processing time

Engineering Contradiction:
Improvegold consumptionVSAvoidpost-plating processing time
Core Design Contradiction:
Loss of substanceVSLoss of time

Solution Approach 1:

The selective additives in the plating solution act as intermediaries that prevent gold deposition on undesired areas during the plating process itself. This eliminates the need for subsequent removal operations, as no unwanted gold deposits are formed in the first place, thereby saving significant post-plating processing time while maintaining reduced gold consumption

Inventive Principle:
Principle #24Intermediary (Mediator)

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 efficient, selective gold deposition on desired areas, reducing unnecessary metal consumption and improving storage stability, resulting in faster plating speeds and improved work efficiency with broad current density applicability, suitable for industrial use.

Implementation Method 1

electrolytic gold plating solution

Methodology Applied
Scientific EffectElectroplating: Electroplating

Implementation Method 2

gold deposition can be restricted to areas where gold is desired

Methodology Applied
Scientific EffectSelective deposition: Deposition (physical)

Data Source

PatentEP2458036B1Gold electroplating solution
Publication Date: 2019.02.27 DUPONT ELECTRONIC MATERIALS INT LLC

AI summary

A gold plating bath and a plating method is disclosed where gold cyanide or salts thereof provide the source of gold, a cobalt compound, and a reaction product of compound containing at least a nitrogen-containing heterocyclic compound and an epihalohydrin. The gold plating bath has high deposition selectivity.