Composite Panel Forming via Foam Substrate Gas Displacement

Solution Overview

Problem

Traditional methods for forming composite panels, such as those used in doors and windows, face issues like warping due to temperature and humidity changes, structural failures from adhesive delamination, and high production costs, particularly with compression moulding processes that require expensive stainless steel moulds and high pressures.

Innovation Solution

A method involving a sheet-form moulding material applied to a substrate with a porous, open-celled structure that allows gas displacement during pressing, reducing the pressure required for bonding and eliminating the need for separate skin and core formation, using a foam substrate to facilitate gas escape and improve bonding strength.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If compression moulding is used to form skins separately, then structural strength is improved, but production cost increases due to expensive stainless steel moulds and high pressure requirements

Engineering Contradiction:

Improvestructural strengthVSAvoidproduction cost

Core Design Contradiction:

StrengthVSEase of manufacture

Solution Approach 1:

The patent combines the skin formation and core bonding operations into a single compression moulding process. The skin-forming composition is applied to the substrate in the mould cavity, and both are cured together in one operation, eliminating the need for separate skin formation and adhesive bonding steps. This merging of operations reduces production cost and complexity while maintaining structural strength.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent uses a foam substrate as an intermediary that serves multiple functions: it provides the core structure, enables gas escape during curing through its open-cell structure, and facilitates bonding with the skin-forming composition. This intermediary substrate eliminates the need for expensive stainless steel moulds and high pressure requirements while maintaining structural integrity.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Adaptability or versatility

If adhesive bonding is used to join skins and core, then assembly flexibility is improved, but reliability deteriorates due to adhesive delamination under certain conditions

Engineering Contradiction:

Improveassembly flexibilityVSAvoidbonding reliability

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The patent merges the skin formation and core bonding operations into a single compression moulding process. The skin-forming composition is applied to the substrate in the mould cavity, and both are cured together in one operation, eliminating the need for separate skin formation and adhesive bonding steps. This merging of operations reduces production cost and complexity while maintaining structural strength.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent replaces chemical adhesive bonding with mechanical and chemical bonding through compression moulding. The skin-forming composition is compressed against the substrate under heat and pressure, creating a strong bond through both mechanical interlocking and chemical curing. This substitution eliminates adhesive delamination issues while maintaining assembly flexibility.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Productivity

If heat bonding is used to join layers, then bonding speed is improved, but applicability deteriorates because it requires heat-softenable materials and controlled temperature conditions

Engineering Contradiction:

Improvebonding speedVSAvoidmaterial applicability

Core Design Contradiction:

ProductivityVSAdaptability or versatility

Solution Approach 1:

The patent combines the skin formation and core bonding operations into a single compression moulding process. The skin-forming composition is applied to the substrate in the mould cavity, and both are cured together in one operation, eliminating the need for separate skin formation and adhesive bonding steps. This merging of operations reduces production cost and complexity while maintaining structural strength.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent changes the bonding mechanism from heat-softening to compression curing. Instead of requiring materials to be heat-softenable, the process uses compression moulding with heat and pressure to cure the skin-forming composition directly onto the substrate. This parameter change expands material applicability while maintaining bonding speed through the efficiency of the combined operation.

Inventive Principle:

Principle #35Parameter changes

4Object-generated harmful factors

If SMC is folded to form a block for compression moulding, then gas release is improved, but pressure requirement increases to 1000-1200 tonnes

Engineering Contradiction:

Improvegas releaseVSAvoidpressure requirement

Core Design Contradiction:

Object-generated harmful factorsVSStress or pressure

Solution Approach 1:

The patent uses a foam substrate as an intermediary that serves multiple functions: it provides the core structure, enables gas escape during curing through its open-cell structure, and facilitates bonding with the skin-forming composition. This intermediary substrate eliminates the need for expensive stainless steel moulds and high pressure requirements while maintaining structural integrity.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent employs a foam substrate with an open-cell porous structure that allows gas to escape during the compression moulding process. This porous structure eliminates the need to fold the SMC to create gas escape paths, thereby reducing the pressure requirement from 1000-1200 tonnes to a much lower level while still enabling effective gas release.

Inventive Principle:

Principle #31Porous materials

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 method reduces production costs and complexity by lowering the pressure needed for forming composite products, enhancing bonding strength, and allowing for the creation of composite panels with improved thermal stability and surface finish without the need for expensive moulds or adhesives.

Implementation Method 1

the configuration of the substrate is such that gas and/or vapour can be displaced from the pressing region

Methodology Applied

Scientific EffectGas displacement through porous structure: Porosity

Implementation Method 2

pressing the sheet-form material to the substrate

Methodology Applied

Scientific EffectCompression bonding: Compression

Implementation Method 3

The mould is closed and pressure is applied to press the moulding compound so that it spreads to all parts of the mould. Heat and pressure is applied until the moulded material has cured.

Methodology Applied

Scientific EffectCuring:

Data Source

PatentUS11904557B2Composite products

Publication Date: 2024.02.20 ACELL IND LTD

AI summary

A method of forming a composite product is described. An example of the method comprises providing a layer (34) comprising a sheet-form moulding material and providing a substrate (36). The layer of sheet-form material is applied onto a surface of the substrate (36); and pressed to the substrate in a mould (30). In some examples, the substrate (36) is an open celled foam and gas and/or vapour can be displaced from the pressing region.