Wood Panel Stability via Layered Adhesive and Fiber Alignment

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Wood-based panels with a middle layer of sticks exhibit strong rippling and torsion due to climate and temperature changes, limiting their size and stability, especially in fire conditions.

Innovation Solution

The use of urea formaldehyde adhesive for gluing outer layers to the middle layer and white or starch glue for gluing the rods within the middle layer, ensuring wood fibers are parallel, reduces waviness and twisting, enhancing stability and allowing larger formats while maintaining fire protection properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If wood-based panels use a middle layer of sticks with parallel wood fibers, then fire resistance and structural stability are improved, but surface waviness increases due to climate and temperature changes

Engineering Contradiction:
Improvefire resistanceVSAvoidsurface waviness
Core Design Contradiction:
ReliabilityVSShape

Solution Approach 1:

The patent applies composite materials by combining a middle layer of sticks with outer layers of wood-based material. This composite structure provides fire resistance through the stick layer's parallel fiber arrangement while outer layers compensate for surface waviness, achieving both fire protection and acceptable surface quality.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent applies local quality by having different layers serve different functions: the middle stick layer provides fire resistance and structural stability with parallel fibers, while outer layers provide surface quality. Each layer is optimized for its specific local function within the overall panel structure.

Inventive Principle:
Principle #3Local quality

2Stability of the object's composition

If wood-based panels use a middle layer of sticks perpendicular to outer layers, then torsion resistance is improved, but weight increases limiting larger formats

Engineering Contradiction:
Improvetorsion resistanceVSAvoidpanel weight
Core Design Contradiction:
Stability of the object's compositionVSWeight of stationary object

Solution Approach 1:

The patent uses composite materials with a middle stick layer oriented perpendicular to outer layers, creating a structurally efficient configuration that provides high torsion resistance. This composite design achieves enhanced stability without proportionally increasing weight, enabling larger panel formats.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent applies segmentation by dividing the panel into distinct layers with the middle stick layer providing structural reinforcement. This segmented approach allows the panel to achieve high torsion resistance through the perpendicular fiber orientation while managing overall weight for larger formats.

Inventive Principle:
Principle #1Segmentation

3Ease of manufacture

If wood-based panels use traditional gluing methods, then manufacturing simplicity is maintained, but fire protection properties deteriorate due to flammable adhesives

Engineering Contradiction:
Improvegluing processVSAvoidfire protection
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The patent applies parameter changes by modifying the adhesive properties to be fire-retardant while maintaining ease of manufacture. The use of fire-retardant adhesives changes the chemical parameters of the bonding agent, providing fire protection without significantly complicating the manufacturing process.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent converts the potential harm of flammable adhesives into a benefit by using fire-retardant adhesive formulations. This transforms the adhesive from a fire risk into a fire protection element, maintaining manufacturing simplicity while enhancing fire safety properties.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

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 results in a stable, low-waviness, large-format wood-based panel with improved fire resistance, where the middle layer remains intact during a fire as the outer layers char first, supported by heat-resistant glues, achieving high stability and prolonged fire endurance.

Implementation Method 1

the outer layers are glued to the middle layer by means of a first glue, that the rods of the middle layer are glued to one another with a second glue, that the first glue as 'surface glue' is a urea formaldehyde adhesive (KUF)

Methodology Applied
Scientific EffectAdhesive bonding: Adhesive

Implementation Method 2

the second glue as 'middle layer glue' is a white or starch glue... the second glue, which is designed as a highly heat-resistant white or starch glue

Methodology Applied
Scientific EffectAdhesive bonding: Adhesive

Implementation Method 3

the alignment of the wood fibers or capillaries essentially parallel to one another, the layer of sticks only increases their thickness when exposed to heat, but not in other dimensions, so that no shearing or twisting forces occur in this respect

Methodology Applied
Scientific EffectThermal expansion: Thermal Expansion

Implementation Method 4

in the event of a fire, the middle layer of the wood-based material board according to the invention proves to be its most stable supporting element, which is only exposed to the flames last because the outer layer chars or burns off first

Methodology Applied
Scientific EffectCharring: Pyrolysis

Data Source

PatentEP2030747B1Lightweight building slab and manufacturing method
Publication Date: 2010.02.17 MORALT TISCHLERPLATTEN
  • EP2030747B1 patent drawingFigure 1
  • EP2030747B1 patent drawingFigure 2

AI summary

The plate (10) has a middle layer (5) and an external layer (9) that are bonded to a central position by a paste (6). The external layer is made of wood and designed as a chip board, medium density fiberboard, veneer or plywood layer and a cotton wood plywood layer. The middle layer is formed as a rod layer with a set of rods that are bonded together by another paste. A set of wood fibers i.e. capillaries, runs parallel to each other and at right angle to the external layer. The former paste is urea formaldehyde adhesive and the latter paste is white or strong glue.