Ink-Receiving Layer Zeta Potential Beading Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Glossy recording media used in ink jet recording methods face issues with beading when recording with pigment ink at high speeds, leading to grainy nonuniformity and reduced printing speed, while existing solutions compromise on image quality and gloss.

Innovation Solution

A recording medium with a substrate and two ink-receiving layers, where the first layer has a positive surface zeta potential and the second layer has a negative surface zeta potential, using inorganic particles like fumed silica or alumina with controlled particle sizes to reduce beading and enhance image development.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Shape

If a single ink-receiving layer with inorganic particles is used to achieve high gloss, then surface smoothness is improved, but beading occurs during high-speed pigment ink recording

Engineering Contradiction:
Improvesurface smoothnessVSAvoidprinting speed
Core Design Contradiction:
ShapeVSProductivity

Solution Approach 1:

The ink-receiving layer is divided into two distinct layers: a first ink-receiving layer containing inorganic particles (such as silica or alumina) with average primary particle size of 50 nm or less that provides high gloss and surface smoothness, and a second ink-receiving layer without inorganic particles or with fewer inorganic particles that enables high-speed pigment ink recording by reducing beading. This segmentation allows each layer to perform its specialized function independently.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different regions of the ink-receiving structure are given different properties: the first ink-receiving layer (closer to the substrate) has high inorganic particle content for gloss, while the second ink-receiving layer (closer to the ink application surface) has low or no inorganic particles to facilitate ink absorption and prevent beading during high-speed recording.

Inventive Principle:
Principle #3Local quality

2Shape

If inorganic particles are added to the ink-receiving layer to enhance gloss, then surface finish is improved, but image uniformity deteriorates due to beading

Engineering Contradiction:
Improvesurface finishVSAvoidimage uniformity
Core Design Contradiction:
ShapeVSManufacturing precision

Solution Approach 1:

The ink-receiving layer is segmented into two layers with different inorganic particle contents. The first layer contains inorganic particles for gloss, while the second layer has reduced or no inorganic particles to ensure uniform ink absorption and prevent beading, thereby maintaining image uniformity during high-speed recording.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The second ink-receiving layer is designed with local quality differences - having fewer or no inorganic particles compared to the first layer - to create a region that promotes uniform ink distribution and absorption, preventing the grainy nonuniformity and beading that would otherwise occur on highly glossy surfaces.

Inventive Principle:
Principle #3Local quality

3Quantity of substance

If a thick ink-receiving layer is used to improve ink absorption, then ink uptake is enhanced, but gloss is reduced

Engineering Contradiction:
Improveink absorptionVSAvoidgloss
Core Design Contradiction:
Quantity of substanceVSShape

Solution Approach 1:

The total ink-receiving layer thickness is distributed across two layers: the first layer (closer to substrate) has greater thickness with inorganic particles for gloss, while the second layer (closer to surface) has smaller thickness without inorganic particles for ink absorption. This segmentation allows the system to achieve both high gloss and adequate ink absorption capacity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different thicknesses are assigned to different regions/layers: the first ink-receiving layer has larger thickness to provide gloss and structural support, while the second ink-receiving layer has smaller thickness optimized for rapid ink absorption, thereby achieving both gloss and ink uptake without compromise.

Inventive Principle:
Principle #3Local quality

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

The solution effectively reduces beading during high-speed pigment ink recording and improves color development for both pigment and dye inks, maintaining high gloss and image quality.

Implementation Method 1

The first ink-receiving layer has a positive surface zeta potential

Methodology Applied
Scientific EffectElectrostatic attraction: Ion Repulsion/Attraction

Implementation Method 2

The second ink-receiving layer has a negative surface zeta potential

Methodology Applied
Scientific EffectElectrostatic repulsion: Ion Repulsion/Attraction

Implementation Method 3

The first inorganic particles are particles of at least one material selected from the group consisting of fumed silica, fumed alumina, and hydrated alumina. The first inorganic particles having an average primary particle size of 50 nm or less

Methodology Applied
Scientific EffectAdsorption: Adsorption

Data Source

PatentUS11945252B2Recording medium and ink jet recording method
Publication Date: 2024.04.02 CANON KK

AI summary

A recording medium includes a substrate, a first ink-receiving layer, and a second ink-receiving layer adjacent to the first ink-receiving layer, in this order. The first ink-receiving layer has a positive surface zeta potential, and the second ink-receiving layer has a negative surface zeta potential. The thickness of the second ink-receiving layer is 2 μm to 15 μm.