Composite Resin Particles for Uniform Sheet Formation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current paper manufacturing methods, such as pulp molding, require large amounts of water and energy, and existing dry methods using thermal fusion-bondable resin face challenges with resin detachment and uniformity during air-laid web formation.

Innovation Solution

A sheet manufacturing apparatus and method utilizing resin particles with a portion of their surface covered by inorganic fine particles, achieving an absolute charging amount of 40 µC/g or higher, which enhances attachment and reduces detachment during web formation, allowing for the production of sheets with improved strength and uniformity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If the particle diameter of the resin is reduced to improve uniformity of distribution, then the uniformity of resin distribution between fibers is improved, but the resin easily detaches from between the fibers during web formation

Engineering Contradiction:
Improveuniformity of resin distributionVSAvoidresin attachment stability
Core Design Contradiction:
Manufacturing precisionVSReliability

Solution Approach 1:

The patent uses composite resin particles consisting of organic resin particles combined with inorganic particles (such as metal oxides or carbon particles) on the surface. This composite structure allows the particles to maintain small size for uniform distribution while the inorganic surface components provide enhanced attachment properties that prevent detachment during web formation

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent modifies the surface properties of resin particles by controlling the particle diameter within a specific range (5-50 μm) and adjusting the content of inorganic particles (1-50 wt%). These parameter changes optimize both the uniformity of distribution and the attachment stability, resolving the contradiction between fine dispersion and retention

Inventive Principle:
Principle #35Parameter changes

2Manufacturing precision

If pulp molding is used to achieve favorable uniformity in fiber deposition, then the uniformity of paper surface is improved, but large volumes of water are required and energy consumption increases

Engineering Contradiction:
Improveuniformity of fiber depositionVSAvoidwater consumption
Core Design Contradiction:
Manufacturing precisionVSQuantity of substance

Solution Approach 1:

The patent extracts and eliminates the water medium from the traditional pulp molding process. By using dry fiber mixing and air-laid web formation without water, the method achieves favorable uniformity in fiber deposition while completely avoiding the water consumption and energy-intensive dewatering and drying steps required by conventional pulp molding

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent replaces the water-based suspension system with an air-based transport and deposition system. Fibers and resin particles are mixed and deposited using air flow and mechanical conveyance, substituting the hydraulic system of pulp molding with a pneumatic-mechanical system that achieves similar uniformity without water

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Strength

If thermal fusion-bondable resin powder is used for bonding fibers, then fiber bonding is achieved, but the resin detaches from between the fibers during air-laid web formation

Engineering Contradiction:
Improvefiber bondingVSAvoidresin retention during forming
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The patent employs composite resin particles where inorganic particles are attached to the surface of organic resin particles. This composite structure provides dual functionality: the organic resin component enables thermal fusion bonding of fibers, while the inorganic surface component (metal oxides or carbon particles) enhances attachment stability and prevents detachment during air-laid web formation

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent applies different properties to different parts of the resin particle system. The core resin particles provide bonding capability through thermal fusion, while the surface inorganic coating provides retention and attachment stability. This local differentiation of properties allows simultaneous achievement of strong bonding and reliable retention during forming

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 apparatus effectively prevents resin detachment and ensures uniform bonding, resulting in sheets with enhanced mechanical strength and improved uniformity, while reducing water and energy consumption.

Implementation Method 1

an absolute value of an average charging amount of the composite is 40 μC/g or higher

Methodology Applied
Scientific EffectElectrostatic charge: Electrostatics

Data Source

PatentEP3626884B1Sheet manufacturing composite
Publication Date: 2023.12.20 SEIKO EPSON CORP
  • EP3626884B1 patent drawingFigure 1
  • EP3626884B1 patent drawingFigure 2A~3

AI summary

A sheet manufacturing apparatus includes a mixing unit that mixes fibers and a composite in the atmosphere, a forming unit that deposits and heats a mixture mixed by the mixing unit to form a sheet; in which the composite is resin particles with at least a portion of a surface coated by inorganic fine particles, and an absolute value of an average charging amount of the composite is 40 µC/g or higher.