Small PET Carbonated Beverage Containers with Optimized Weight Distribution

Solution Overview

Problem

Small PET containers for carbonated beverages face challenges in maintaining carbonation retention and shelf life due to unpredictable performance when applying standard light-weighting methods, particularly in harsh climates, and existing designs fail to optimize weight distribution efficiency and material orientation effectively.

Innovation Solution

The solution involves optimizing the weight distribution efficiency and reducing the proportion of amorphous polymer in PET containers by selectively reducing material in the preform neck and end cap, combined with design and shape optimizations, to achieve improved carbonation retention and shelf life, even at low weights.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Weight of moving object

If standard light-weighting methods are applied to small PET containers, then the weight of the container is reduced, but carbonation retention and shelf life deteriorate in an unpredictable and severe manner

Engineering Contradiction:

Improvecontainer weightVSAvoidcarbonation retention

Core Design Contradiction:

Weight of moving objectVSReliability

Solution Approach 1:

The patent applies local quality by selectively reducing material thickness in specific regions (neck and end cap) while maintaining optimal wall thickness in other critical areas. This localized approach allows weight reduction without compromising the structural integrity and gas barrier properties needed for carbonation retention, resolving the contradiction between lightweight design and reliable carbonation retention.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent changes key parameters including weight distribution efficiency (targeting 95% or higher), crystallinity content (increasing to 10-30%), and wall thickness distribution. These parameter modifications enable the container to achieve both reduced weight and improved carbonation retention by optimizing the material structure rather than simply reducing material quantity.

Inventive Principle:

Principle #35Parameter changes

2Weight of moving object

If standard light-weighting methods are applied to small PET containers, then the weight of the container is reduced, but shelf life deteriorates

Engineering Contradiction:

Improvecontainer weightVSAvoidshelf life

Core Design Contradiction:

Weight of moving objectVSDuration of action of stationary object

Solution Approach 1:

The patent applies local quality by selectively reducing material thickness in specific regions (neck and end cap) while maintaining optimal wall thickness in other critical areas. This localized approach allows weight reduction without compromising the structural integrity and gas barrier properties needed for carbonation retention, resolving the contradiction between lightweight design and reliable carbonation retention.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent employs composite material strategies by combining PET with crystallizing agents and using multi-layer structures where appropriate. This creates a composite system that provides both lightweight properties and enhanced barrier characteristics, extending shelf life while maintaining reduced weight.

Inventive Principle:

Principle #40Composite materials

3Weight of moving object

If the amount of polymer is reduced to make smaller containers, then the weight is reduced, but volume to surface area ratio deteriorates

Engineering Contradiction:

Improvecontainer weightVSAvoidvolume to surface area ratio

Core Design Contradiction:

Weight of moving objectVSVolume of moving object

Solution Approach 1:

The patent changes key parameters including weight distribution efficiency (targeting 95% or higher), crystallinity content (increasing to 10-30%), and wall thickness distribution. These parameter modifications enable the container to achieve both reduced weight and improved carbonation retention by optimizing the material structure rather than simply reducing material quantity.

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

This approach significantly improves carbonation retention and shelf life in small PET containers by enhancing weight distribution efficiency and crystallinity, while maintaining light weight, and when used with coatings, provides enhanced creep performance and gas barrier properties.

Implementation Method 1

permeation is generally dependent on material characteristics such as the percent (%) crystallinity, orientation, surface area, and material thickness

Methodology Applied

Scientific EffectPermeation: Permeation

Implementation Method 2

Creep is primarily determined by container geometry and material distribution

Methodology Applied

Scientific EffectCreep: Creep

Implementation Method 3

Sorption is related to the amount of gas (CO2) that can dissolve in the PET itself

Methodology Applied

Scientific EffectSorption: Sorption

Data Source

PatentUS11801964B2Small carbonated beverage packaging with enhanced shelf life properties

Publication Date: 2023.10.31 THE COCA COLA CO

AI summary

This disclosure provides new containers, preforms, methods, and designs for small and light-weight carbonated beverage packaging that provide surprisingly improved carbonation retention and greater shelf life, while still achieving light weight. This disclosure is particularly drawn to small PET containers for carbonated beverages, for example less than or about 400 mL, and methods and designs for their fabrication that attain unexpectedly good carbonation retention and shelf life.