Image Forming Apparatus Pre-Post Processing Liquid Segmentation

Solution Overview

Problem

Conventional inkjet image forming methods often result in images on printing media that are prone to peeling when scraped, due to the insolubility or coagulation of coloring agents in the ink, leading to abrasion issues.

Innovation Solution

An image forming apparatus and method that includes pre- and post-processing units applying specific liquids to the printing medium before and after image formation, with amounts determined by the type of medium, to enhance abrasion resistance and image quality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a processing liquid is applied before and after inkjet printing to improve image quality, then the image density and environmental resistance are improved, but the coloring agent becomes insoluble or coagulated causing the image to peel off when scraped

Engineering Contradiction:

Improveimage fastnessVSAvoidabrasion resistance

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The processing liquid is divided into two distinct segments: a pre-processing liquid applied before inkjet printing and a post-processing liquid applied after inkjet printing. Each liquid has different functional compositions that work together to improve image fastness without causing peeling. The pre-processing liquid prepares the substrate surface, while the post-processing liquid enhances the image properties, thereby resolving the contradiction between image fastness and abrasion resistance.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The invention changes the chemical parameters of the processing liquids by specifying different compositions for pre-processing and post-processing liquids. The pre-processing liquid contains specific solvents and additives that prepare the substrate, while the post-processing liquid contains different components that enhance image density and resistance. By controlling the chemical parameters and sequence of application, the invention achieves both improved image fastness and maintained abrasion resistance.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If the processing liquid makes the coloring agent insoluble to improve water resistance, then the environmental resistance is improved, but the image peels off when scraped against objects

Engineering Contradiction:

Improveenvironmental resistanceVSAvoidabrasion resistance

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The processing liquid is divided into two distinct segments: a pre-processing liquid applied before inkjet printing and a post-processing liquid applied after inkjet printing. Each liquid has different functional compositions that work together to improve image fastness without causing peeling. The pre-processing liquid prepares the substrate surface, while the post-processing liquid enhances the image properties, thereby resolving the contradiction between image fastness and abrasion resistance.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The invention changes the chemical parameters of the processing liquids by specifying different compositions for pre-processing and post-processing liquids. The pre-processing liquid contains specific solvents and additives that prepare the substrate, while the post-processing liquid contains different components that enhance image density and resistance. By controlling the chemical parameters and sequence of application, the invention achieves both improved image fastness and maintained abrasion resistance.

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

The solution significantly improves the abrasion resistance and quality of images on printing media by applying pre- and post-processing liquids, preventing peeling and enhancing environmental resistance, water resistance, and image density.

Implementation Method 1

a pre-processing unit configured to apply a pre-processing liquid to the surface of the printing medium before the image is formed by the image forming unit, and a post-processing unit configured to apply a post-processing liquid different from the pre-processing liquid to the surface of the printing medium after the image is formed

Methodology Applied

Scientific EffectSurface treatment:

Data Source

PatentUS9840092B2Image forming apparatus using a pre-processing liquid and a post-processing liquid, and an image forming method using a pre-processing liquid and a post-processing liquid

Publication Date: 2017.12.12 RICOH CO LTD

AI summary

Disclosed is an image forming apparatus including an image forming unit that ejects droplets from an image forming apparatus, and forms an image on a surface of a printing medium, a pre-processing unit that applies a pre-processing liquid to the surface of the printing medium before the image is formed by the image forming unit, and a post-processing unit that applies a post-processing liquid different from the pre-processing liquid to the surface of the printing medium after the image is formed by the image forming unit. The pre-processing unit applies an amount of the pre-processing liquid which is determined based on a type of the printing medium and the post-processing unit applies an amount of the post-processing liquid which is determined based on the type of the printing medium.