Folded Release Liner Adhesive Assembly for On-Body Injectors

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing on-body medical fluid injection devices face challenges in securely adhering to patient skin during and after injection, particularly when dealing with varying body shapes and requiring easy removal without causing discomfort or damage.

Innovation Solution

An on-body medical fluid injection device with a flexible skin adhesive structure, featuring a removable release liner with bi-folded film segments that expose the adhesive upon device removal from a support, allowing for easy application and conformation to body curves, and a non-adhesive edge for strain relief.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a connector is used to attach the cartridge to the syringe barrel, then the cartridge can be securely held, but the connector creates additional parts that increase device complexity and potential failure points

Engineering Contradiction:
Improvecartridge attachment reliabilityVSAvoiddevice complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The connector is integrated directly into the syringe barrel structure, merging two previously separate components (barrel and connector) into a single unified structure. This eliminates the need for a separate connector piece while maintaining the attachment function, thereby reducing device complexity and potential failure points.

Inventive Principle:
Principle #5Merging (Combining)

2Strength

If adhesive is applied to the connector to improve cartridge attachment, then attachment strength increases, but residual adhesive creates contamination risks and cleaning requirements

Engineering Contradiction:
Improvecartridge attachment strengthVSAvoidadhesive contamination
Core Design Contradiction:
StrengthVSObject-affected harmful factors

Solution Approach 1:

The adhesive application surface is separated from the connector and relocated to the syringe barrel interior. This extraction removes the source of contamination (adhesive on the connector) while preserving the bonding function, as adhesive is now applied only where it will be contained during the attachment process.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The syringe barrel interior acts as an intermediary controlled environment for adhesive application. By applying adhesive to the barrel interior rather than directly to the connector, the system creates a contained intermediate step that prevents adhesive from becoming a contaminant on external surfaces.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Manufacturing precision

If manual alignment and attachment of cartridge to syringe barrel are required, then precise positioning can be achieved, but the process requires significant operator skill and time

Engineering Contradiction:
Improvecartridge alignment precisionVSAvoidattachment ease of operation
Core Design Contradiction:
Manufacturing precisionVSEase of operation

Solution Approach 1:

Alignment features (protrusions and recesses) are pre-formed on the cartridge and syringe barrel during manufacturing. This preliminary action ensures that when the components are brought together, alignment is automatically achieved without requiring manual adjustment or high operator skill, thus maintaining precision while improving ease of operation.

Inventive Principle:
Principle #10Preliminary action

4Ease of manufacture

If the syringe barrel interior is used to hold adhesive, then adhesive application is simplified, but the adhesive must remain stable under varying storage and handling conditions

Engineering Contradiction:
Improveadhesive application easeVSAvoidadhesive stability
Core Design Contradiction:
Ease of manufactureVSStability of the object's composition

Solution Approach 1:

The adhesive formulation is modified with specific properties (viscosity, curing characteristics, temperature stability) to ensure it remains stable during storage and handling while maintaining applicability. By changing the chemical parameters of the adhesive, it can withstand varying conditions without degrading or becoming difficult to apply.

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

Facilitates secure and comfortable adhesion to patient skin, enhances conformation to body shapes, and simplifies removal by reducing manual effort and minimizing skin contact during the process.

Implementation Method 1

an adhesive assembly (40) including an adhesive (42) and a syringe barrel (20, 40)

Methodology Applied
Scientific EffectAdhesive bonding: Adhesive

Data Source

PatentEP3694582B1Injection device with adhesive assembly
Publication Date: 2026.04.29 ENABLE INJECTIONS INC
  • EP3694582B1 patent drawingFigure 1a~1b
  • EP3694582B1 patent drawingFigure 2~4a
  • EP3694582B1 patent drawingFigure 4b~4c

AI summary

An on-body medical fluid injection device with adhesive assembly includes a housing, an injection needle, a skin-facing surface that faces the skin of a patient when on the patient's body, a skin adhesive carried by at least a portion of the skin facing surface and a plurality of substantially contiguous folded film segments covering the skin adhesive.