Lead-Free Solder Filtration and Fatty Acid Coating for Fine PCB Mounting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional soldering methods result in poor appearance with protrusions and bumps, solder bridges causing short-circuits, and lack of flowability, leading to increased CO2 emissions and aesthetic issues in precision manufacturing, particularly for micro components like micro LEDs, and mixing of solids like oxides during tin article production.
Innovation Solution
A method involving heating and melting a raw material mixture of tin with a secondary metal element, followed by filtration through a filter with aperture sizes not exceeding 10 μm to remove solids, and cooling to form a solder product with improved flowability and a surface layer of carboxylic acid to prevent oxidation and enhance durability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional soldering methods are used, then soldering process is simple, but solder has poor appearance with protrusions and bumps
Solution Approach 1:
The patent applies preliminary action by filtering the molten solder through a filter with aperture of 1 μm or less before the soldering process. This removes solid particles in advance, preventing protrusions and bumps on the solder appearance, while maintaining a relatively simple soldering process.
2Reliability
If conventional soldering methods are used, then soldering process is straightforward, but solder bridges cause short-circuits
Solution Approach 1:
The patent removes solid particles from molten solder through filtration before soldering. This preliminary purification prevents solder bridges and short-circuits by ensuring clean, uniform solder flow, thereby improving electrical connection reliability without significantly complicating the process.
3Productivity
If conventional solder product is used, then soldering material is readily available, but solder lacks flowability leading to increased CO2 emissions
Solution Approach 1:
The patent changes the physical parameters of solder by filtering out solid particles to achieve a smoother, more fluid solder consistency. This improves solder flowability, allowing for more efficient soldering processes that use less material and reduce energy consumption and CO2 emissions.
4Ease of manufacture
If solids mix into molten metal during tin article manufacture, then manufacturing process is simple, but bending and cutting become difficult
Solution Approach 1:
The patent applies preliminary filtration to remove solid particles from molten tin during the manufacturing process. This prevents solids from interfering with subsequent bending and cutting operations, improving workability while adding only a simple filtration step to the process.
5Manufacturing precision
If conventional soldering is used for micro components, then component mounting is straightforward, but solids project from solder pocket causing inclined mounting
Solution Approach 1:
The patent filters molten solder through a fine mesh filter (aperture 1 μm or less) before micro component soldering. This removes all solid particles that could project from the solder pocket, ensuring proper component alignment and preventing inclined mounting, while maintaining process simplicity.
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 method enables finer, high-quality soldering with reduced likelihood of inclined mounting, increased adhesion, and improved aesthetics, eliminating the need for nickel and gold plating, and reducing environmental impact by minimizing solder usage and oxidation.
Implementation Method 1
a filtration step of filtering the molten metal with a filter having an aperture size of not more than 10 μm
Implementation Method 2
a heating step of heating and melting a raw material to obtain a molten metal
Implementation Method 3
a cooling step of cooling and solidifying the filtered molten metal
Data Source
AI summary
A solder product 20 includes: a lead-free solder part 21 containing tin as a main component and a metal element other than lead as a secondary component; and a carboxylic acid having 10 to 20 carbons, the carboxylic acid being mainly distributed over the surface of the solder product 20 to form a surface layer 22. The carboxylic acid is preferably a fatty acid having 12 to 16 carbons, and more preferably a palmitic acid.