Contact Lens Using Low Molecular Weight Polyamide for Surface Wettability

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Soft contact lenses often lack sufficient comfort and wettability, leading to reduced wear time due to their initial poor oxygen permeability and comfort issues, which existing manufacturing processes are unable to adequately address.

Innovation Solution

A contact lens manufacturing method involving a reactive mixture comprising a silicone component, low molecular weight polyamide, high molecular weight polyamide, and a diluent, cured within a mold and extracted using an aqueous solution to enhance comfort and wettability by releasing polyamide onto the lens surface during wear.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If soft contact lenses are made from hydrogels, then comfort is improved, but initial comfort and wettability are poor

Engineering Contradiction:

ImprovecomfortVSAvoidinitial comfort and wettability

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The patent incorporates low molecular weight polyamide into the lens matrix before use, which then migrates to the lens surface during initial wear to provide immediate wettability enhancement. This preliminary incorporation allows the lens to self-enhance its surface properties during the first few wears, addressing the poor initial comfort issue without requiring pre-coating or external treatment.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent changes the molecular weight parameter of the polyamide component, using low molecular weight polyamide (LMWP) specifically. This parameter change enables the polyamide to migrate to the lens surface more effectively, providing dynamic wettability enhancement. The specific parameter range (low molecular weight) is critical for achieving the desired surface migration and wettability improvement.

Inventive Principle:

Principle #35Parameter changes

2Productivity

If contact lenses are designed for multiple uses, then productivity is improved, but comfort and wettability deteriorate over time

Engineering Contradiction:

Improvemultiple usesVSAvoidcomfort and wettability

Core Design Contradiction:

ProductivityVSEase of operation

Solution Approach 1:

The patent creates a dynamic system where the low molecular weight polyamide continuously migrates from the lens bulk to the lens surface during wear. This dynamic migration process ensures that the lens surface is continuously replenished with wettability-enhancing polyamide, maintaining comfort and wettability properties throughout multiple uses rather than degrading over time.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The lens contains its own wettability enhancement mechanism through the incorporated low molecular weight polyamide. During normal wear, the polyamide naturally migrates to the surface and provides wettability enhancement without requiring external intervention, cleaning solutions, or manual re-coating. This self-service mechanism maintains comfort across multiple uses.

Inventive Principle:

Principle #25Self-service

3Reliability

If polyamide is incorporated into the lens, then wettability is improved, but manufacturing complexity increases

Engineering Contradiction:

ImprovewettabilityVSAvoidmanufacturing process

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges the wettability enhancement function directly into the lens manufacturing process by incorporating low molecular weight polyamide into the reactive mixture before curing. This combining approach integrates the wettability enhancement step with the base lens fabrication, eliminating the need for separate surface coating or post-processing steps, thus avoiding significant manufacturing complexity.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent uses a composite material approach by combining low molecular weight polyamide with the hydrogel lens matrix. This composite structure allows the polyamide to be distributed throughout the lens bulk and migrate to the surface, providing wettability enhancement while using a relatively simple manufacturing process that is compatible with existing contact lens fabrication methods.

Inventive Principle:

Principle #40Composite materials

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 method significantly increases the comfort and wettability of contact lenses, allowing for longer wear times by incorporating low molecular weight polyamide, which is released during wear, thereby improving lens performance.

Implementation Method 1

Some of this polyamide would be released from within the lens to the lens' surface during wearing

Methodology Applied

Scientific EffectDiffusion: Diffusion

Implementation Method 2

curing said reactive mixture within said mold to form said contact lens

Methodology Applied

Scientific EffectPolymerization: Photopolymerisation

Data Source

PatentEP2864110B1Lens comprising low and high molecular weight polyamides

Publication Date: 2016.12.21 JOHNSON & JOHNSON VISION CARE INC

AI summary

The present invention relates to a contact lens formed from components including (i) at least one silicone component, (ii) at least one low molecular weight polyamide having a weight average molecular weight of less than 200,000, and (iii) at least one high molecular weight polyamide having a weight average molecular weight of greater than 200,000, wherein the low molecular weight polyamide does not contain a reactive group.