UV Cured Time-Temperature Indicator Manufacturing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing time-temperature indicator (TTI) devices face challenges in manufacturing due to rapid diffusion and reaction of activator and indicator layers, leading to premature reaction and increased costs, making it difficult to produce multilayer devices efficiently and economically.
Innovation Solution
The use of UV curing binders allows for the application and curing of layers quickly, preventing premature reaction by using UV light to cure the binders in seconds, enabling direct contact and curing of reactive layers, and the creation of single-layer devices by mixing solid reactants in a non-solvent medium, preventing initial reaction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional application and drying methods are used for multi-layer TTI devices, then layers can be applied sequentially, but premature reaction occurs between activator and indicator layers due to rapid diffusion
Solution Approach 1:
The patent changes the physical-chemical parameters of the binder by using UV-curable binders instead of conventional drying binders. The UV curing process rapidly polymerizes the binder upon UV light exposure, immediately immobilizing the activator and indicator layers to prevent diffusion-based premature reaction, while enabling continuous high-speed manufacturing.
Solution Approach 2:
The patent applies preliminary action by pre-curing each layer with UV light immediately after application. This preliminary curing action stabilizes each layer before the next layer is applied, ensuring that reactive components are locked in place before they can diffuse and react prematurely, while maintaining rapid production throughput.
2Reliability
If conventional drying methods are used to prevent premature reaction, then layer stability is improved, but production time and costs increase
Solution Approach 1:
The patent replaces the thermal drying mechanism with a photochemical curing mechanism. Instead of using heat to evaporate solvents and dry layers (which takes time and energy), UV light directly initiates polymerization of the binder, rapidly forming stable layers without the need for prolonged drying time, thus reducing both time and energy consumption.
Solution Approach 2:
The patent utilizes the phase transition of the binder from liquid (uncured) to solid (cured) through UV-induced polymerization. This phase transition occurs rapidly upon UV exposure, providing immediate layer stability without requiring the slow evaporation process of conventional drying, thereby eliminating the time-loss contradiction.
3Productivity
If UV curing is used to rapidly cure binders and prevent premature reaction, then manufacturing efficiency is improved, but equipment complexity increases
Solution Approach 1:
The patent introduces UV-curable binders as an intermediary material that enables rapid curing. These binders contain photoinitiators that activate upon UV exposure to trigger rapid polymerization. The intermediary UV curing system, while adding equipment, provides precise control over the curing process and enables high-speed manufacturing that outweighs the equipment complexity burden.
4Reliability
If activator and indicator are kept in separate layers to prevent premature reaction, then reaction control is improved, but device thickness and complexity increase
Solution Approach 1:
The patent maintains the segmentation principle of keeping activator and indicator in separate layers, each stabilized by UV-cured binder. This segmentation prevents premature reaction while the rapid UV curing minimizes the required separation distance and overall device thickness, resolving the contradiction between reaction control and device compactness.
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 enables the rapid and economical production of multilayer and single-layer TTI devices without premature reaction, extending shelf life and service life, and allows for precise control of color change and activation energy through layer thickness and reactant concentration.
Implementation Method 1
UV Ink/Binder: A type of radiation-curing ink that dries, cures or sets with the application of ultraviolet light can be used for making the indicating devices. UV curing inks are composed of polymerizable fluid oligomers (short chain polymers), monomers (light-weight molecules and that bind together to form polymers), polymer and initiators that, when exposed to ultraviolet radiation, release free radicals (extremely reactive atoms or molecules that can destabilize other atoms or molecules and start rapid chain reactions) that cause the polymerization of the vehicle/binder, which hardens to a dry ink or soft adhesive film containing the ingredient of the coating.
Data Source
AI summary
This invention relates to thin indicating devices, such as time-temperature indicators and a method of making by applying and UV curing one or more layers of indicating composition are disclosed. For example, an indicator layer is applied on substrate and cured with UV light, immediately followed by an application of an activator layer which is cured by UV light. The device can have other layers, such as a permeable barrier between the activator and indicator layer and a top protective layers which are also UV cured. This fast curing method prevents premature reactions, e.g., diffusion of activator into indicator layer and vice versa during manufacturing.