Method for inactivating bacteria or viruses and inactivating apparatus for bacteria or viruses
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Solution Overview
Problem
Ultraviolet light sterilization at wavelengths of 200 nm to 235 nm generates a strange odor when used to inactivate bacteria or viruses on surfaces due to the decomposition of human sebum, leading to detectable odorous components like nonenal, hexanal, and heptanal.
Innovation Solution
Irradiating ultraviolet light with specific parameters, such as irradiance (X) and integrated irradiation dose (Y) within two hours, satisfying formulas like 0<Y<10.704X−0.373 or 0<Y<0.4534X−0.697, to inactivate bacteria or viruses while minimizing odor generation, using an apparatus with a light source emitting ultraviolet light in the 200 nm to 235 nm range and a controller to regulate emission intensity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If ultraviolet light with wavelength 200 nm to 235 nm is used for sterilization, then sterilization effectiveness is improved, but strange odor is generated due to sebum decomposition
Solution Approach 1:
The patent applies parameter changes by precisely controlling the wavelength range (200-235 nm), irradiance (X), and integrated irradiation dose (Y) to achieve effective sterilization while suppressing odor generation. The mathematical relationship Y < 10.704X - 0.373 defines the optimal parameter space that resolves the contradiction between sterilization effectiveness and odor control.
Solution Approach 2:
The patent employs dynamic control of the ultraviolet light source, allowing adjustment of irradiance and irradiation time based on the mathematical relationship provided. This dynamic approach enables the system to adapt to different surfaces and contamination levels while maintaining optimal sterilization-odor balance.
2Productivity
If high irradiance ultraviolet light is applied for short time, then sterilization speed is improved, but odor generation is increased
Solution Approach 1:
The patent transforms the static sterilization approach into a dynamic parameter-controlled process. By establishing the mathematical relationship between irradiance (X) and integrated irradiation dose (Y), the system can optimize the combination of intensity and duration to achieve fast sterilization without exceeding the odor threshold defined by Y < 10.704X - 0.373.
Solution Approach 2:
The patent enables periodic or intermittent irradiation patterns where the ultraviolet light source can be turned on and off in cycles. This allows accumulation of effective sterilization dose while controlling peak irradiance exposure time, thereby preventing excessive odor generation during high-intensity periods.
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
Effectively inactivates bacteria or viruses while suppressing the generation of strong odors, ensuring the odor index remains below detectable levels, even with intermittent irradiation, and maintaining air ventilation to remove any accumulated odor.
Implementation Method 1
DNA shows the highest absorption characteristics at wavelengths around 260 nm
Implementation Method 2
A technique of using a low-pressure mercury lamp for sterilization is widely availed
Implementation Method 3
Squalene, a kind of sebum, produces squalene monohydroperoxide (SQHPO) when ultraviolet light is irradiated
Implementation Method 4
the surface of the object is attached with human sebum (e.g., triglycerides, squalene, wax esters, etc.) and free fatty acids (palmitoleic acid) decomposed from the sebum
Data Source
AI summary
Provided are a method and an apparatus for inactivating bacteria or viruses attached to an object while suppressing generation of a strange odor. The method for inactivating bacteria or viruses includes a step (a) of irradiating with ultraviolet light having an optical output at a specific wavelength in a range of 200 nm to 235 nm. The step (a) is a step of irradiating with the ultraviolet light is performed so that an irradiance (X) [mW/cm2] (X>0) and an integrated irradiation dose within two hours (Y) [mJ/cm2] satisfy the following formula (1)0<Y<10.704X−0.373 (1).