Reaction Liquid Control for Ink Fixation in Image Forming Apparatus

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing image forming apparatuses face challenges in efficiently setting the appropriate amount of reaction liquid for ink fixation, leading to issues like image unevenness and density lowering due to the reaction liquid's decrease over time and varying aggregability with different inks.

Innovation Solution

The image forming apparatus incorporates a system to calculate and adjust the reaction liquid amount based on the type of ink and the decrease rate of the reaction liquid on the print medium, using a weight coefficient to ensure adequate ink fixation and prevent image unevenness.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a fixed amount of reaction liquid is used for all inks, then the device complexity is reduced, but image unevenness occurs due to varying aggregability with different inks

Engineering Contradiction:
Improvereaction liquid amount controlVSAvoidimage uniformity
Core Design Contradiction:
Device complexityVSManufacturing precision

Solution Approach 1:

The patent applies local quality by setting different reaction liquid discharge amounts for different ink colors based on their specific aggregability characteristics. Each ink color (cyan, magenta, yellow, black) has a predetermined weight coefficient that adjusts the reaction liquid amount locally according to its chemical properties, thereby achieving uniform image quality across all colors without requiring complex real-time measurement systems.

Inventive Principle:
Principle #3Local quality

2Reliability

If the reaction liquid amount is increased to compensate for decrease over time, then ink fixation reliability is improved, but loss of substance increases

Engineering Contradiction:
Improveink fixationVSAvoidreaction liquid
Core Design Contradiction:
ReliabilityVSLoss of substance

Solution Approach 1:

The patent applies preliminary action by pre-determining weight coefficients for each ink color that account for the reaction liquid decrease rate over time. These coefficients are calculated in advance based on the aggregability characteristics and time-dependent decrease behavior of the reaction liquid. During printing, the system uses these pre-calculated coefficients to adjust reaction liquid amounts, ensuring adequate ink fixation without excessive application, thereby reducing waste while maintaining reliability.

Inventive Principle:
Principle #10Preliminary action

3Manufacturing precision

If the reaction liquid amount is adjusted for each ink type, then image uniformity is improved, but device complexity increases

Engineering Contradiction:
Improveimage uniformityVSAvoidreaction liquid amount control
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent applies parameter changes by modifying the reaction liquid discharge amount parameter based on ink-specific weight coefficients. Instead of implementing complex real-time measurement and adjustment systems, the invention changes the discharge parameter in advance according to the ink color being used. The control unit selects appropriate weight coefficients from predetermined values and adjusts the reaction liquid amount accordingly, achieving precise image uniformity through simple parameter selection rather than complex control mechanisms.

Inventive Principle:
Principle #35Parameter changes

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 effectively suppresses image unevenness and ensures proper ink fixation by accurately determining the reaction liquid amount needed for each ink, even as the reaction liquid decreases over time.

Implementation Method 1

varying aggregability with different inks

Methodology Applied
Scientific EffectAggregability: Coagulation

Data Source

PatentEP4509319A1Image forming apparatus, information processing method, and program
Publication Date: 2025.02.19 CANON KK
  • EP4509319A1 patent drawingFigure 1~2
  • EP4509319A1 patent drawingFigure 3
  • EP4509319A1 patent drawingFigure 4~6

AI summary

There is provided with an image forming apparatus. A deciding means decides a discharge amount of a reaction liquid based on a timing at which the reaction liquid is discharged onto a print medium by the image forming apparatus, a timing at which each of inks of not less than two colors is discharged onto the print medium next to the reaction liquid, and a discharge amount of each of the inks of the not less than two colors by the image forming apparatus. A controlling means controls discharge of the reaction liquid and the inks of the not less than two colors.