Immiscible Fluid Printhead Nozzle Capping

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Inkjet printing devices face issues with 'long term decap' and 'short term decap' leading to fluid evaporation, pigment-ink-vehicle separation, and increased waste and wear due to current methods of cap application and maintenance.

Innovation Solution

Applying an immiscible fluid, such as isoparaffin, to selectively cap the nozzles of a printhead using an immiscible fluid applicator, which prevents evaporation and maintains nozzle functionality during printing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If mechanical caps are used to cover nozzles during storage, then evaporation is prevented, but the printing process is interrupted by cap removal and reapplication

Engineering Contradiction:
Improvenozzle fluid integrityVSAvoidprinting continuity
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

An immiscible fluid (such as oil) is introduced as an intermediary substance that forms a cap over the nozzle opening. This fluid cap prevents evaporation and contamination of the jettable fluid without requiring mechanical intervention, allowing continuous printing operations while maintaining nozzle integrity.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If mechanical caps are removed and reapplied frequently, then nozzle functionality is maintained, but wear and waste increase

Engineering Contradiction:
Improvenozzle functionalityVSAvoidwaste ink and wear
Core Design Contradiction:
ReliabilityVSLoss of substance

Solution Approach 1:

The immiscible fluid automatically forms and maintains a cap over the nozzle through its own surface tension and immiscibility properties with the jettable fluid. This self-forming mechanism eliminates the need for external mechanical cap application and removal, reducing wear on mechanical components and minimizing waste ink generation during servicing routines.

Inventive Principle:
Principle #25Self-service

3Ease of operation

If nozzles are left uncapped during storage, then printing is immediately available, but fluid evaporation and pigment separation occur

Engineering Contradiction:
Improveprinting readinessVSAvoidfluid composition
Core Design Contradiction:
Ease of operationVSStability of the object's composition

Solution Approach 1:

The immiscible fluid acts as a protective intermediary layer that seals the nozzle opening during storage periods. This allows the printhead to be stored without mechanical caps while preventing evaporation and pigment-ink-vehicle separation, maintaining fluid composition stability without interrupting printing readiness.

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

Reduces waste ink generation, minimizes nozzle clogging, and extends printer usage by maintaining fluid integrity and preventing pigment separation, while allowing continuous printing without mechanical cap removal and reapplication.

Implementation Method 1

prevents evaporation and maintains nozzle functionality

Methodology Applied
Scientific EffectEvaporation prevention: Evaporation

Implementation Method 2

selectively applying an immiscible fluid to a surface of a printhead

Methodology Applied
Scientific EffectImmiscibility: Liquid-Liquid Extraction

Data Source

PatentEP3174720B1Applying a cap
Publication Date: 2020.04.15 HEWLETT PACKARD DEVELOPMENT COMPANY LP
  • EP3174720B1 patent drawingFigure 1
  • EP3174720B1 patent drawingFigure 2
  • EP3174720B1 patent drawingFigure 3A~3B

AI summary

A method of applying a cap to a printhead may comprise selectively applying an immiscible fluid to a surface of a printhead in which the immiscible fluid caps a number of nozzles on a number of nozzles defined within the printhead. A printhead may comprise a layer of immiscible fluid in which the immiscible fluid is selectively applied to the surface of the printhead and in which the immiscible fluid caps a number of nozzles defined within the printhead. A printer may comprise a printhead comprising a number of nozzles, an immiscible fluid applicator, and a processor to instruction the immiscible fluid applicator to apply a layer of immiscible fluid to the surface of the printhead.