Si-DLC Coated Plastic Food Container Adhesion

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Plastic food containers with low surface energy, such as polypropylene, struggle to achieve stable adhesion and high oxygen barrier properties with diamond-like carbon (DLC) coatings due to their porous structure, leading to poor adherence and breakdown of the DLC layer.

Innovation Solution

A silicon-incorporated diamond-like carbon (Si-DLC) layer is deposited on a porous plastic container using an intermediate silicon layer, with plasma pretreatment and chemical vapor deposition, enhancing adhesion and mechanical properties without breaking the layer.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a DLC layer is coated on plastic with low surface energy (such as polypropylene), then oxygen barrier properties are improved, but the DLC layer is not stably adhered and breaks off

Engineering Contradiction:

Improveoxygen barrier propertiesVSAvoidadhesion stability

Core Design Contradiction:

ReliabilityVSStability of the object's composition

Solution Approach 1:

A plasma polymerized silane layer is introduced as an intermediary between the polypropylene substrate and the DLC coating. This intermediate layer serves as a bridge that bonds to both the low surface energy plastic surface and the DLC layer, enabling stable adhesion without requiring the DLC to directly contact the porous plastic surface.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The invention changes the surface energy parameter of the plastic by applying plasma treatment, which increases surface energy and creates a more favorable surface for coating adhesion. Additionally, the plasma polymerized silane layer modifies the surface chemistry to enhance bonding capability.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If the thickness of a thin layer deposited on PP is increased, then oxygen barrier properties should be improved, but the layer is taken off or broken due to poor adhesion

Engineering Contradiction:

Improveoxygen barrier propertiesVSAvoidlayer integrity

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The plasma polymerized silane layer acts as a mediating layer that prevents the DLC coating from directly contacting the porous PP surface. This intermediate layer distributes mechanical stresses and provides chemical bonding sites, allowing thicker DLC layers to be applied without breaking or delaminating.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The invention creates a composite structure consisting of three layers: the polypropylene substrate, the plasma polymerized silane intermediate layer, and the DLC coating layer. This composite structure combines the benefits of each material while mitigating their individual weaknesses.

Inventive Principle:

Principle #40Composite materials

3Reliability

If plasma method is used to coat thin layer on PP, then oxygen barrier properties are attempted to be improved, but products cannot be produced due to layer breakdown

Engineering Contradiction:

Improveoxygen barrier propertiesVSAvoidproduct manufacturability

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The plasma polymerized silane layer is applied as an intermediary step before the DLC coating. This intermediate layer is formed through plasma polymerization and provides a stable foundation that enables subsequent DLC coating without layer breakdown, making the manufacturing process viable for producing oxygen barrier products.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The plasma polymerized silane layer is applied as a preliminary treatment before the final DLC coating. This preliminary action prepares the surface by increasing surface energy and creating bonding sites, ensuring that the subsequent DLC layer adheres stably and does not break during manufacturing or use.

Inventive Principle:

Principle #10Preliminary action

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

The Si-DLC layer provides stable high oxygen barrier properties and excellent mechanical characteristics, improving the container's ability to maintain freshness while maintaining cost-effectiveness and recyclability.

Implementation Method 1

A plasma pretreatment may be performed on the surface of the container so as to improve the adhesion between the surface of the container and the intermediate thin layer.

Methodology Applied

Scientific EffectPlasma treatment: Plasma

Implementation Method 2

depositing an intermediate thin layer on the surface of the container; and depositing a Si-DLC layer on the intermediate thin layer

Methodology Applied

Scientific EffectChemical vapor deposition: Chemical Vapour Deposition

Data Source

PatentUS10099837B2Food container having Si-DLC layer and manufacturing method thereof

Publication Date: 2018.10.16 CJ CHEILJEDANG CORP

AI summary

There are provided a food container having a silicon incorporated diamond like carbon (Si-DLC) layer and a method thereof. The food container includes a container made of a plastic material; an intermediate thin layer formed on a surface of the container; and a Si-DLC layer formed on the intermediate thin layer. Accordingly, it is possible to provide porous plastic container having a Si-DLC layer and a manufacturing method thereof, which can implement high oxygen barrier properties and excellent mechanical characteristics by stably depositing a Si-DLC layer on a food container having lower surface energy without breaking the Si-DLC layer.