Balloon Catheter Inner Layer Delamination Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Balloon catheters used in percutaneous transluminal coronary angioplasty face challenges with delamination of the inner layer from the outer layer during production and insertion of the guide wire, leading to potential complications and difficulty in removing the lumen forming core member.
Innovation Solution
The balloon catheter employs a heat-welding process where the outer layer is melted at a temperature higher than the inner layer's melting point, ensuring the outer layer is integrated without melting the inner layer, preventing delamination and allowing easy removal of the core member, with a thermoplastic polymer Shore D hardness range of 63D to 74D for the inner layer and 40D to 55D for the outer layer for adequate flexibility and strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the inside tube is made larger to increase blood perfusion amount, then the perfusion capability is improved, but the stress applied to the outside wall of the inside tube increases making it easier to be crushed or kinked
Solution Approach 1:
The inside tube is constructed as a composite structure with an inner layer made of a first thermoplastic polymer and an outer layer made of a second thermoplastic polymer with different melting points. This composite structure allows the tube to have both flexibility and resistance to crushing or kinking while maintaining adequate blood perfusion capability
Solution Approach 2:
The patent specifies particular melting point ranges for the thermoplastic polymers used in the inner and outer layers. By controlling these thermal parameters, the tube achieves optimal balance between flexibility, structural integrity, and resistance to deformation under pressure
2Strength
If adhesive is used to bond the inside tube and balloon, then the bonding strength is improved, but the bonded part becomes rigid
Solution Approach 1:
The patent replaces adhesive bonding with heat-welding to join the inside tube and balloon. This thermal joining method maintains flexibility at the bonded interface while achieving sufficient bonding strength, eliminating the rigidity problem associated with adhesive bonding
Solution Approach 2:
The heat-welding process utilizes phase transition (melting and solidification) of the thermoplastic polymers to create a strong bond between the inside tube and balloon without introducing rigid adhesive materials, thereby preserving catheter flexibility
3Strength
If the inner layer and outer layer are heat-welded at high temperature to ensure strong bonding, then the bonding strength is improved, but the inner layer may be damaged or delamination may occur
Solution Approach 1:
The patent applies local quality by using thermoplastic polymers with different melting points for the inner and outer layers. The outer layer has a lower melting point than the inner layer, allowing selective melting of the outer layer during heat-welding without damaging the inner layer, thus achieving strong bonding while preserving inner layer integrity
Solution Approach 2:
The patent performs preliminary action by carefully selecting thermoplastic polymers with appropriate melting point differences before the heat-welding process. This pre-established material property difference ensures that during subsequent heat-welding, only the outer layer melts and bonds to the inner layer without causing delamination or inner layer damage
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 effectively prevents delamination of the inner layer, ensures the balloon catheter's structural integrity, and facilitates the production process by allowing easy removal of the core member, enhancing the catheter's flexibility and operational stability.
Implementation Method 1
the outer layer is melted at a temperature higher than the inner layer's melting point
Implementation Method 2
employs a heat-welding process where the outer layer is melted
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
The present invention relates to a balloon catheter that includes a balloon, and a balloon inside tube which passes through an inner lumen of the balloon and includes an inner layer, an outer layer, and a support body. In the balloon catheter, the balloon, the inner layer, and the outer layer are formed of thermoplastic polymers that can be heat-welded to each other. A thermoplastic polymer forming the inner layer has a higher melting point than a thermoplastic polymer forming the outer layer. In the present invention, since the inner layer and the outer layer are formed of thermoplastic polymers that can be heat-welded to each other, delamination of the inner layer of the balloon inside tube can be prevented.