Capillary Wick Heater Layout for Stable Aerosol Delivery

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing aerosol delivery devices with heater elements suffer from degradation of liquid and heater surfaces due to long-term contact, leading to potential toxicant inhalation and overheating issues as the liquid level diminishes.

Innovation Solution

The use of dried conductive fluid to form heater elements on an activation surface of a fluid-transfer article, with channels for air-flow pathways and restricted aerosol precursor release, preventing direct contact between the heater and liquid, and utilizing polymeric wicking material for efficient fluid transfer.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a pressurized canister with propellant is used to deliver nicotine, then nicotine delivery is reliable and controllable, but the device becomes more complex and requires high manufacturing precision

Engineering Contradiction:
Improvenicotine delivery reliabilityVSAvoiddevice complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent extracts the propellant and pressurization system from the device, replacing them with a passive capillary wick structure. The wick material itself provides the pressurization function through capillary action, eliminating the need for separate propellant reservoirs, pressure regulators, and delivery mechanism components.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent applies local quality by using materials with specific capillary properties in the wick structure. The wick material is selected and engineered to have specific pore sizes and surface properties that enable controlled capillary flow, providing localized pressurization exactly where needed without requiring system-wide pressurization mechanisms.

Inventive Principle:
Principle #3Local quality

2Productivity

If a pressurized canister system is used, then nicotine can be delivered effectively, but the manufacturing cost and precision requirements increase significantly

Engineering Contradiction:
Improvenicotine delivery effectivenessVSAvoidease of manufacture
Core Design Contradiction:
ProductivityVSEase of manufacture

Solution Approach 1:

The patent employs a disposable cartridge design where the capillary wick structure is integrated into a single-use unit. The wick and associated components are manufactured as inexpensive, disposable elements that are replaced rather than maintained, eliminating the need for precision manufacturing and complex assembly of durable pressurization systems.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The capillary wick structure is self-regulating and requires no external control systems. The material properties of the wick automatically regulate the flow of nicotine based on capillary forces, eliminating the need for precision-manufactured pressure regulators, flow controllers, or other active delivery mechanism components.

Inventive Principle:
Principle #25Self-service

3Reliability

If conventional pressurized delivery mechanisms are used, then nicotine delivery is reliable, but bacterial growth can occur in the delivery mechanism

Engineering Contradiction:
Improvedelivery mechanism reliabilityVSAvoidbacterial growth
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent extracts the liquid reservoir from direct contact with the delivery mechanism by using the capillary wick as both the reservoir and delivery pathway. This eliminates the separate liquid reservoir and delivery mechanism interface where bacterial contamination typically occurs, as the wick structure itself prevents stagnation and bacterial growth through continuous capillary flow.

Inventive Principle:
Principle #2Taking out (Extraction)

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

Prevents degradation of liquid and heater surfaces, reduces toxicant inhalation risk, and maintains consistent aerosol production by ensuring controlled heat transfer and fluid distribution.

Implementation Method 1

the wick structure may be configured to deliver the nicotine from the reservoir to the heater assembly in the absence of a propellant

Methodology Applied
Scientific EffectCapillary action: Capillary Action

Data Source

PatentEP3941288B1Aerosol delivery system
Publication Date: 2026.04.29 IMPERIAL TOBACCO LTD
  • EP3941288B1 patent drawingFigure 1
  • EP3941288B1 patent drawingFigure 2
  • EP3941288B1 patent drawingFigure 3

AI summary

There is disclosed a fluid-transfer article which is suitable for use as part of an aerosol-generating system of a type which may be used as a smoking substitute. The fluid-transfer article comprises a first region for holding an aerosol precursor and for transferring said aerosol precursor to an activation surface of a second region of said article, said activation surface being disposed at an end of said article. The activation surface has at least one channel therein, with the or each channel opening outwardly of the activation surface. Heater elements are formed on the activation surface between the or each channel, to enable the fluid-transfer article to be heated to release the aerosol precursor as vapour or a mixture of vapour and aerosol. The heater elements are of a dried conductive fluid, with suitable electrical connections. The conductive fluid may be applied by dipping the fluid-transfer article in the fluid to cause the fluid to adhere to, or otherwise coat, the appropriate part or parts of the activation surface. The conductive fluid is then dried, and a voltage can be applied there to cause the heater elements 24 to heat.