PCB Imaging via Aqueous Alkaline Soluble UV Blocking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The electronics industry faces challenges in proper alignment and registration during the manufacture of printed circuit boards, leading to misregistration issues, inefficiencies, and costly scrap boards due to the difficulty in removing UV blocking compositions from textured surfaces like through-holes and vias.
Innovation Solution
A method involving the application of an aqueous alkaline soluble UV photosensitive material, an aqueous soluble UV transparent film, and an aqueous alkaline soluble UV blocking composition, which are selectively exposed to UV radiation and then simultaneously removed with an aqueous alkaline solution, allowing for efficient imaging and planarization of substrates like printed circuit boards.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If UV blocking composition is applied to textured surfaces with through-holes and vias, then imaging coverage is improved, but removal difficulty increases and ink is wasted
Solution Approach 1:
Aqueous alkaline soluble release dots are applied to the substrate before the UV blocking composition. These release dots create a preliminary pattern that guides selective removal, allowing the UV blocking composition to be easily removed from through-holes and vias while remaining on flat areas, thus solving both the coverage and removal difficulty problems
2Manufacturing precision
If through-holes and vias are filled with UV block ink, then imaging completeness is improved, but ink removal becomes difficult and board continuity is lost
Solution Approach 1:
Aqueous alkaline soluble release dots serve as an intermediary layer between the substrate and UV blocking composition. This intermediary enables selective removal of the UV blocking composition from through-holes and vias using aqueous alkaline solution, preventing loss of board continuity while maintaining imaging completeness
3Adaptability or versatility
If multiple fixed phototools are prepared manually, then registration flexibility is improved, but process time and inaccuracy increase
Solution Approach 1:
The system transitions from static fixed phototools to a dynamic digital imaging system. A digital image of the desired pattern is projected onto the substrate, allowing real-time adjustment and optimization of registration without manual phototool changes, thus reducing process time while maintaining flexibility
Solution Approach 2:
Instead of using physical phototools, a digital copy or image of the desired pattern is projected onto the substrate. This digital imaging approach eliminates the need for multiple physical phototools while maintaining registration flexibility and significantly reducing preparation time
4Ease of manufacture
If conventional solvents are used for removal, then removal effectiveness is improved, but environmental friendliness and safety decrease
Solution Approach 1:
The invention changes the chemical parameter of the removal agent from conventional organic solvents to aqueous alkaline solution. This parameter change maintains removal effectiveness for the aqueous alkaline soluble release dots and UV blocking composition while eliminating environmental and safety hazards associated with toxic solvents
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
This method is fast, economical, and environmentally friendly, preventing unwanted deposition of UV blocking compositions in apertures and other areas, reducing waste and improving manufacturing efficiency by eliminating the need for separate removal steps and toxic solvents.
Implementation Method 1
exposing the aqueous alkaline soluble UV photosensitive material to UV radiation except to regions covered with the aqueous alkaline soluble UV blocking composition
Implementation Method 2
simultaneously removing the aqueous alkaline soluble UV blocking composition, the aqueous soluble UV transparent film and selective portions of the aqueous alkaline soluble UV photosensitive material with an aqueous alkaline solution
Data Source
AI summary
Substrates, such as printed circuit boards, are coated with an aqueous alkaline developable UV photosensitive material followed by applying an aqueous soluble UV transparent film to coat the UV photosensitive material. An aqueous alkaline soluble UV blocking composition is selectively applied to the surface of the UV blocking film to function as a mask. UV light is applied to portions of the UV photosensitive material not covered by the mask. The UV blocking composition, UV transparent film and selective sections of the UV photosensitive material are simultaneously removed with an aqueous alkaline developer solution to form an image on the substrate.