Multi-Substrate Liquid Supply Path Design for Sealing and Flow
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing liquid ejection heads face challenges in achieving high sealing properties and joining strength between substrates while maintaining a sufficient liquid supply path width, which is essential for efficient liquid ejection and preventing leakage or mixing of different liquids.
Innovation Solution
The substrate design includes a first substrate through hole and a second substrate through hole that communicate to form a liquid supply path, with specific width relationships (D1 < D2 and D3 < D2) to enhance joining strength and supply path efficiency, and a manufacturing method that forms the second substrate through hole by etching using a substrate joining material as a mask.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the joint area between the element substrate and the support member is increased to enhance sealing property, then the sealing property is improved, but the opening portion of the supply path cannot be made large enough
Solution Approach 1:
The patent transitions from a single-substrate design to a multi-substrate stacked architecture, where the supply path extends through multiple layers (first substrate through hole, second substrate through hole, third substrate through hole). This dimensional expansion allows the supply path to achieve sufficient width for high-speed liquid ejection while the joint areas between substrates maintain adequate sealing properties.
Solution Approach 2:
The element substrate is divided into multiple separate substrates (first substrate, second substrate, third substrate) that are joined together. Each substrate can be independently manufactured and optimized, allowing the supply path openings in different substrates to be sized appropriately for both sealing and liquid flow requirements.
2Productivity
If the opening portion of the supply path is made large to increase liquid supply width, then the liquid ejection speed is improved, but the joint area is reduced and joining strength is weakened
Solution Approach 1:
The supply path is extended into the third dimension by creating through holes in multiple stacked substrates. This allows the liquid supply width to be increased through the cumulative effect of multiple opening portions (D1, D2, D3) while each individual joint area remains sufficient for strong bonding.
Solution Approach 2:
Different opening portions of the supply path are positioned at different locations and have different width characteristics. The opening portions in the first and third substrates can be optimized for liquid supply width, while the joint areas between substrates maintain adequate bonding surface area.
3Productivity
If a multilayer substrate structure is used with different opening areas, then the supply path width can be increased, but the joining strength at some interfaces is reduced
Solution Approach 1:
Each substrate in the multilayer structure has locally optimized opening portions tailored to its specific function. The first substrate has opening portion D1 optimized for liquid entry, the second substrate has opening portion D2 for intermediate flow, and the third substrate has opening portion D3 for final supply to the pressure chamber. This local optimization allows efficient liquid supply while maintaining adequate joint areas.
Solution Approach 2:
The patent utilizes a stacked three-substrate configuration where the supply path extends vertically through all layers. This vertical dimensionality allows the horizontal opening areas at each level to be optimized independently, achieving both high liquid supply efficiency and adequate joining strength at each interface.
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 configuration increases the joining strength of the substrate with other members, suppresses peeling or damage, and allows for efficient liquid supply and ejection, while maintaining a wide joint area and supporting high-density energy generating element placement.
Implementation Method 1
introducing an etching liquid from the first substrate through hole of the first substrate directly or indirectly overlapping the second substrate so that the etching liquid reaches the second substrate, and forming the second substrate through hole directly or indirectly communicating with the first substrate through hole in the second substrate
Data Source
AI summary
A substrate includes a first substrate which has a first substrate through hole, and a second substrate which has a second substrate through hole and directly or indirectly overlaps the first substrate, the first substrate through hole and the second substrate through hole directly or indirectly communicate with each other to form a liquid supply path and a width D1 of an opening portion of the first substrate through hole on a surface of the first substrate closer to the second substrate, a width D2 of an opening portion of the second substrate through hole on a surface of the second substrate closer to the first substrate, a width D3 of an opening portion of the second substrate through hole on a surface of the second substrate farther from the first substrate have a relationship of D1<D2 and D3<D2.