Multilayer Resin Preform Molding for Vertical-Striped Containers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for manufacturing resin containers with vertical-striped patterns face challenges in precisely controlling the injection of multiple resin types and forming complex color patterns, leading to complicated and expensive apparatus configurations.
Innovation Solution
A manufacturing method involving two-stage injection molding to create a multilayer preform, where a first layer is formed with a groove pattern, followed by injecting a second resin of a different color into these grooves, and then blow-molding the preform to form a resin container with a vertical-striped pattern.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Shape
If multiple types of resin are simultaneously injected to form a multilayer preform with vertical-striped patterns, then the aesthetic appearance and gas barrier properties are improved, but the device complexity and manufacturing cost increase significantly
Solution Approach 1:
The injection molding process is segmented into two sequential stages: first injecting a base resin to form the main container body, then injecting a different colored resin to form the vertical-striped pattern layer. This segmentation allows each injection to be controlled independently, simplifying the apparatus configuration compared to simultaneous multi-resin injection while achieving the desired complex color pattern.
Solution Approach 2:
The first resin is injected and allowed to partially cool and set before the second resin is injected. This preliminary action creates a stable base layer that guides the flow of the second resin, ensuring precise formation of the vertical-striped patterns without requiring complex real-time control mechanisms.
2Reliability
If multiple types of resin are simultaneously injected to form a multilayer preform, then the gas barrier property is improved, but the manufacturing precision and stability of the intermediate layer decrease
Solution Approach 1:
The multilayer structure is created through segmented sequential injection rather than simultaneous injection. The first resin forms the base layer with good gas barrier properties, and the second resin is subsequently injected to form the patterned intermediate layer. This segmentation allows precise control over the width, position, and shape of each layer independently.
Solution Approach 2:
The injection parameters (temperature, pressure, injection rate) are changed between the two injection stages to optimize the formation of each layer. The first injection uses parameters optimized for gas barrier resin, while the second injection uses parameters optimized for creating the vertical-striped pattern, achieving both high manufacturing precision and desired aesthetic appearance.
3Productivity
If residual heat from injection molding is utilized for blow-molding, then the manufacturing efficiency is improved, but the control over the blowing process becomes more difficult
Solution Approach 1:
The temperature parameters of the preform are utilized from the injection molding process without additional heating or cooling. The residual heat maintains the preform at an optimal temperature range for blow-molding, allowing the thermoplastic material to be sufficiently pliable for forming while still providing enough structural control for precise mold filling and pattern formation.
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 allows for the stable formation of vertical-striped patterns with precise control over resin layers, reducing manufacturing complexity and cost while enhancing the aesthetic appeal of resin containers.
Implementation Method 1
a first injection molding process for injection-molding a first layer of a preform by using a first resin material
Implementation Method 2
a second injection molding process for injecting a second resin material into the groove of the first layer, the second resin material having a color that is different from a color of the first resin material, and laminating a second layer on an outer peripheral side or an inner peripheral side of the first layer
Implementation Method 3
a blow-molding process for blow-molding a preform that includes multiple layers and has been obtained in the second injection molding process in a state where residual heat at a time of injection molding is contained
Implementation Method 4
in a state where residual heat at a time of injection molding is contained
Data Source
AI summary
A manufacturing method of a resin container includes: a first injection molding process for injection-molding a first layer of a preform by using a first resin material, the preform having a bottomed cylindrical shape and including a groove that extends in an axis direction; a second injection molding process for injecting a second resin material into the groove of the first layer, the second resin material having a color that is different from a color of the first resin material, and laminating a second layer on an outer peripheral side or an inner peripheral side of the first layer; and a blow-molding process for blow-molding a preform that includes multiple layers and has been obtained in the second injection molding process in a state where residual heat at a time of injection molding is contained, and manufacturing the resin container having a vertical-striped color pattern formed by using the second layer.