Prepreg Tape Tack Control for High-Speed Automatic Lamination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing prepreg tapes face challenges in achieving low adhesive property at room temperature for easy unwinding, appropriate hardness for feeding to a laminating head, and sufficient adhesive property at 30°C to 60°C for sticking to a mold, which hinders high-speed automatic lamination and increases production costs.
Innovation Solution
A prepreg tape with controlled tack values and drape values within specific ranges at 23°C and 45°C, combined with a thermosetting resin composition, ensures low adhesive property at room temperature for easy unwinding, appropriate hardness for feeding, and increased adhesive property at 30°C to 60°C for sticking, suitable for automated lamination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the adhesive property at room temperature is reduced to enable high-speed unwinding, then the prepreg tape can be unwound at high speed without twining, but the adhesive property at 30°C to 60°C may become insufficient for proper sticking to the mold
Solution Approach 1:
The invention changes the chemical composition parameters of the thermosetting resin system, specifically using a novolak-type epoxy resin combined with a polyfunctional amine curing agent. This chemical parameter change creates a resin system with distinct temperature-dependent adhesive behavior: low tack at room temperature for easy unwinding, but sufficient adhesive strength at 30-60°C for proper bonding to the mold surface.
Solution Approach 2:
The invention creates a composite resin system by combining multiple resin components (novolak-type epoxy resin as base resin, polyfunctional amine curing agent, and optional accelerator) that work synergistically. This composite material approach allows the resin to exhibit different adhesive properties at different temperatures, resolving the contradiction between low-room-temperature-adhesion and high-temperature-adhesion requirements.
2Reliability
If the adhesive property at room temperature is increased to improve sticking to the mold, then the prepreg tape sticks better, but the prepreg tape cannot be unwound at high speed due to twining
Solution Approach 1:
The invention adjusts the adhesive parameter (tack value) to a specific range (0.03 to 0.08 N/cm) at room temperature by selecting appropriate resin composition parameters. This controlled parameter change ensures the prepreg has minimal stickiness at room temperature for high-speed unwinding, while maintaining sufficient adhesive strength at elevated temperatures for proper mold adhesion.
3Strength
If the hardness at room temperature is increased to maintain shape during feeding, then the prepreg tape can be fed to the laminating head, but the prepreg tape becomes too rigid for proper conformability
Solution Approach 1:
The invention optimizes the resin content and viscosity parameters to achieve a balanced mechanical property profile. The resin composition and content are controlled so that the prepreg has sufficient stiffness at room temperature to maintain its shape during feeding operations, yet remains flexible enough to conform to the mold surface when heated and pressed.
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
Enables high-speed automatic lamination with reduced twining and improved sticking, resulting in high-quality fiber-reinforced composite materials with enhanced mechanical properties and reduced production costs.
Implementation Method 1
adhesive property so that the prepreg tape easily sticks to the molding jig such as a mold or the prepreg tape of a lower layer (previously laminated) by being heated at the laminating head portion at about from 30°C to 60°C
Data Source
Figure 1
AI summary
A prepreg tape in which reinforcing fiber bundles are impregnated with a thermosetting resin composition, wherein the prepreg tape has a tack value measured at 23°C at a plunger push pressure of 90 kPa of 5-40 kPa, a tack value measured at 45°C and a plunger push pressure of 150 kPa of 35-100 kPa, and a drape value at 23°C of 10-40°, and includes unidirectional fibers arranged along the direction of length of the prepreg tape.