The air catalyst “King of Air / AT254”, which was developed as a countermeasure against sick house syndrome, was commissioned to Nara Medical University to verify the inactivation of the new coronavirus.

[Test result announcement]
The air catalyst “King of Air / AT254”, which was developed as a countermeasure against sick house syndrome, was commissioned to Nara Medical University to verify the inactivation of the new coronavirus.
~ The reduction rate associated with the inactivation of the new coronavirus was demonstrated 99.887% effectiveness~

Bless Co., Ltd. (Head Office: Chuo-ku, Osaka, Representative Director: Tetsuhiro Nishizaki) conducted verification for the new coronavirus inactivation by “King of Air / AT254 (All Titanium AT254-V)” at the Department of Microbial Infectious Diseases, Nara Medical University School of Medicine, and announced the test results. AT254 is an air catalyst solution mainly composed of titania-based ceramic coating agent, which was developed in 2006 as antifouling, antifungal, antibacterial and sick house syndrome measures.

The test virus used was a new type of coronavirus (SARS-CoV-2; 2019-nCoV JPN / TY / WK-521 strain). In a demonstration experiment conducted by Nara Medical University, it was reported that the new coronavirus was inactivated by 78.754% in 30 minutes, 97.626% in 60 minutes and 99.887% in 120 minutes as the first air-catalyzed solution in Japan.

Contract Research Report by Department of Microbial Infectious Diseases of Nara Medical University School of Medicine


■ Changes in virus infectivity

* Control = raw glass plate

■ Virus inactivation effect and reduction rate

The product used in this demonstration experiment is AT254※1, which was developed in 2006 as a countermeasure against sick house syndrome and pollen.   AT254 facilitates redox reaction between oxygen and water in the air and repeatedly decompose toxic substances after it is sprayed over indoor walls or furniture with a spray gun.  The antibacterial and antiviral effects last for a long time.   Stronger infection prevention is expected using both instantaneous measures (disinfectant) and standing measures (AT254).


■ Kobe Municipal Subway Coating Work Scene


Based on the results of antiviral performance evaluation test using Type A Influenza and Feline Coronavirus conducted in 2019 by the Kitasato Research Center for Environmental Science, Kitasato University, AT254 was introduced in a wide range of industries, companies, facilities, etc. as early as spring of 2020 with expectation that it will be effective against aerial infection of coronavirus.  Users include major restaurant chains, medical malls, public transportation companies, shrines and temples receiving visitors at the year-end and New Year holidays.


In addition, the “King of Air / AT254 Air Conditioner Filter”※2, which was developed in 2016 as an item that utilizes air conditioners, supports the purification of indoor air by utilizing the internal circulation function of the air conditioner.  In addition to antifouling and antifungal effects inside the air conditioner, it receives high evaluation for reducing electricity bill.


Now that the values for indoor air have changed, as a leading company that prepares the air environment through “King of Air / AT254”, we will continue to provide antibacterial and antiviral products that performs “visible relief = filter, invisible safety = coating”.


※1 “King of Air / AT254”

Since it is an air catalyst, it is colorless and transparent and can be installed anywhere regardless of the environmental conditions.  The main component, the titania-based ceramic coating agent, inactivates bacteria and viruses in the air by the oxidation radical reaction (= air catalyst) with oxygen on their spikes, and bacteria and viruses are decomposed into water and carbon dioxide.  This effect is safe and lasts for a long time. Since it is an air catalyst, it is effective for 24 hours at places without light, in shade, or at night.  It can be coated on most places and objects (excluding cultural properties, works of art, precision machinery, etc.).  The average effect of air catalysts lasts 3 to 5 years.


※2 “King of Air / AT254 Air Conditioner Filter” is a high-performance air conditioner filter that contains AT254 and has antifouling, antifungal, deodorant and pollen prevention effects. Taking the test result forward, we are planning to conduct antiviral demonstration test with the air conditioner filters.


■ “King of Air / AT254 Coating Product Overview   ※ Business use only
Name: King of Air / AT254
Product name: All titanium AT-254-V
Capacity: 4L / container
Main components: silica, phosphorus pentoxide, alumina
How to use: Air gun spray

■ “King of Air / AT254 Air Conditioner Filter” Product Overview   ※ For ceiling cassettes / for wall hangings
Main component: Non-woven fabric, AT254 impregnated
How to use: Attach with special tape to the intake surface of the air conditioner
Sticker as an infection prevention PR for stores

General purchase: King of Air EC site

■ Introduction record (partial)
Kobe Electric Railway
Hanshin train
Kobe Municipal Subway
Kobe City Bus
MK Taxi, etc.

■ The “antiviral test” conducted this time is distinguished from “sterilization / eradication”, which temporarily kills / removes viruses and bacteria. Air catalyst coating exert its effect gradually after hardened.

■ Inactivating effect of “King of Air / AT254” recognized by the research institute
Antiviral performance evaluation tests completed by Kitasato Research Center for Environmental Science, Kitasato University
* Evidence for Type A Influenza virus
* Feline Coronavirus
Total 254 bacteria (antibacterial 70, antifungal 159 and anti-algae 25) have been verified for effectiveness.

Bless Co., Ltd.
Established: January 1997
Head Office: 4-7-4 Kawaramachi, Chuo-ku, Osaka
Representative Director: Tetsuhiro Nishizaki
Home page:
Business: Manufacturing and sales of All Titanium AT254 and AT254 Filter / Commercial air conditioner cleaning and house cleaning / Manufacturing and sales of air conditioning hygiene products