Liquid Ejection Head Flow Path Accuracy via Dry Film Etching

Solution Overview

Problem

Existing methods for manufacturing liquid ejection heads face accuracy issues due to variations in filling depth and surface unevenness when filling through holes with fillers, leading to inaccuracies in forming flow path members.

Innovation Solution

A method involving the partial insertion of a dry film into a substrate's supply path, followed by etching to create a flat etched surface parallel to the substrate, allowing for precise formation of a flow path member using a mold, thereby enhancing the accuracy of the liquid ejection head manufacturing process.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If a through hole is filled with a filler by bringing a tape or glass plate into contact with the substrate surface, then the filling process can be performed, but the filling depth varies and the surface becomes uneven, resulting in poor accuracy in forming the flow path member

Engineering Contradiction:

Improveaccuracy in forming flow path memberVSAvoidsurface unevenness and filling depth variation

Core Design Contradiction:

Manufacturing precisionVSShape

Solution Approach 1:

The dry film is disposed on the substrate surface before the filler filling process, serving as a preliminary protective layer. This preliminary action prevents the filler from directly contacting the substrate surface, thereby maintaining surface flatness and uniform filling depth, which resolves the accuracy issue in forming the flow path member

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The dry film acts as an intermediary layer between the substrate surface and the filler. By introducing this intermediate element, the harmful direct contact between filler and substrate is eliminated, preventing surface unevenness and depth variation while still allowing the filler to be properly contained and formed

Inventive Principle:

Principle #24Intermediary (Mediator)

2Manufacturing precision

If the dry film is etched from the side facing the first surface of the substrate, then the etched surface becomes flat and parallel to the substrate, but additional etching process steps are required

Engineering Contradiction:

Improveflatness of etched surfaceVSAvoidnumber of process steps

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The dry film is disposed on the substrate surface before the filler filling process, serving as a preliminary protective layer. This preliminary action prevents the filler from directly contacting the substrate surface, thereby maintaining surface flatness and uniform filling depth, which resolves the accuracy issue in forming the flow path member

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The dry film acts as an intermediary layer between the substrate surface and the filler. By introducing this intermediate element, the harmful direct contact between filler and substrate is eliminated, preventing surface unevenness and depth variation while still allowing the filler to be properly contained and formed

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

This approach ensures accurate manufacturing of liquid ejection heads by maintaining the flatness of the etched surface, improving the dimensional accuracy and uniformity of the flow path member, resulting in a high-precision liquid ejection head.

Implementation Method 1

etching the dry film from a side of the dry film facing the first surface of the substrate so that the dry film has an etched surface substantially in parallel with the first surface

Methodology Applied

Scientific EffectEtching:

Data Source

PatentUS9789690B2Method for manufacturing liquid ejection head

Publication Date: 2017.10.17 CANON KK

AI summary

A method for manufacturing a liquid ejection head includes the steps of: preparing a substrate including an energy-generating element disposed on a first surface of the substrate and a supply path for liquid; disposing a dry film on the first surface of the substrate in such a manner that the dry film partially enters the supply path; etching the dry film from a side of the dry film facing the first surface of the substrate so that the dry film has an etched surface substantially in parallel with the first surface and covers the supply path; forming a resin layer to be a flow path member on the dry film covering the supply path; and removing the dry film covering the supply path.