Polylactide Fibre Filter Material Biodegradability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional cigarette filter materials, such as cellulose acetate, are slow to degrade due to their poor biodegradability and require plasticizers that act as binders, reducing the degradability and adsorption efficiency of semi-volatile compounds.

Innovation Solution

A filter material comprising polylactide fibres with added plasticizers like PEG, triacetin, and triethyl citrate, which act as true plasticizers rather than binders, enhancing mechanical properties and adsorption characteristics while maintaining biodegradability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If cellulose acetate is used as filter material, then mechanical strength and fibre binding are improved, but biodegradability deteriorates

Engineering Contradiction:
Improvemechanical strengthVSAvoidbiodegradability
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The patent changes the chemical composition parameter from cellulose acetate to polylactide polymer, which fundamentally alters the material's biodegradation behavior while maintaining mechanical properties through appropriate polymer selection and processing parameters

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite material system combining polylactide polymer with plasticizers, where the plasticizer component provides fibre binding and mechanical strength while the polylactide base maintains biodegradability, resolving the contradiction between strength and biodegradation

Inventive Principle:
Principle #40Composite materials

2Strength

If plasticizer is added to bind fibres, then mechanical strength is improved, but degradability deteriorates

Engineering Contradiction:
Improvemechanical strengthVSAvoiddegradability
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The patent changes the plasticizer concentration parameter to optimal levels that provide sufficient fibre binding without excessive binding that would prevent degradation, and selects specific plasticizer types that are themselves biodegradable, resolving the contradiction between binding strength and degradability

Inventive Principle:
Principle #35Parameter changes

3Strength

If plasticizer is added to improve mechanical properties, then fibre binding is improved, but adsorption efficiency of semi-volatile compounds deteriorates

Engineering Contradiction:
Improvefibre bindingVSAvoidadsorption efficiency
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The patent optimizes the plasticizer concentration parameter to a specific range that provides adequate fibre binding while leaving sufficient surface area and porosity available for adsorption of semi-volatile compounds, and selects plasticizer types with appropriate chemical properties that do not interfere with adsorption functionality

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 use of polylactide fibres with plasticizers improves the selective removal of semi-volatile compounds and taste characteristics of smoke, while ensuring biodegradability and mechanical strength, outperforming conventional cellulose acetate filters in terms of adsorption efficiency.

Implementation Method 1

The plasticizer acts by binding adjacent fibres to one another at their contact points, thereby affording the filter rods sufficient hardness for cigarette manufacture and use

Methodology Applied
Scientific EffectAdhesion: Adhesive

Implementation Method 2

Biodegradable polymers disposed of in bioactive environments degrade by the enzymatic action of microorganisms such as bacteria, fungi and algae. Their polymer chains may also be cleaved by non-enzymatic processes such as chemical hydrolysis

Methodology Applied
Scientific EffectBiodegradation: Decomposition (biological)

Implementation Method 3

the addition of a plasticizer which binds fibres actually can result in a reduction in the degradability of the filter material. The binding of the fibres certainly slows the separation of the individual fibres making up the tow in a spent smoking article, thus maintaining the bundle of fibres and reducing their exposure to the elements that will carry out any degradation process

Methodology Applied
Scientific EffectAdsorption: Adsorption

Data Source

PatentEP2723201B1Filter material comprising polylactide fibres
Publication Date: 2018.08.08 BRITISH AMERICAN TOBACCO (INVESTMENTS) LTDA
  • EP2723201B1 patent drawingFigure 1
  • EP2723201B1 patent drawingFigure 2
  • EP2723201B1 patent drawingFigure 3

AI summary

The invention relates to filter material for inclusion in the filter or filter element of a 5 smoking article, said filter material comprising polylactide fibres and a plasticizer. The invention also relates to filters or filter elements comprising the filter material, and smoking articles comprising the same.