With the Establishment of 'Severe Heat Days', External Cooling Needs Rise in the 40°C Era: Prepare for Heatstroke with Ice Packs Surpassing 1 Million Cumulative Shipments

Peacock Vacuum Bottle Co., Ltd. (hereinafter referred to as Peacock Vacuum Bottle, Headquarters: Osaka City, President: Chika Yamanaka) is expanding its 'Ice Pack Series,' which realizes 'portable cooling,' against the backdrop of the increasingly severe intense heat environment in recent years.

In 2026, with the new definition of 'severe heat days' indicating a maximum temperature of 40°C or higher, the summer heat is expected to become even more severe than before. What becomes crucial in such an environment is 'measures to lower body temperature' in addition to hydration.

The Ice Pack is a portable cooling item that evolves the function of an ice bag to suit modern lifestyles. It combines the convenience of being immediately usable even outdoors and the practicality of efficiently cooling the body, and is utilized in various scenes such as commuting, school, sports, and leisure.

Product Details: https://www.the-peacock.co.jp/blogs/feature/pickup21
https://www.the-peacock.co.jp/blogs/feature/abc-150

■ The Establishment of 'Severe Heat Days' and the Normalization of the WBGT Danger Zone; Heatstroke Remains at a High Level

In 2026, the Japan Meteorological Agency newly defined days with a maximum temperature of 40°C or higher as 'severe heat days.' This indicates that dangerously hot weather threatening life, surpassing the conventional 'extremely hot days (35°C or higher),' is becoming an everyday occurrence.

Furthermore, according to the WBGT (Wet Bulb Globe Temperature) published by the Ministry of the Environment:
- 28°C or higher: Severe Warning
- 31°C or higher: Danger
In recent summers, the WBGT has reached the danger level of 31°C or higher during many daytime hours.

Ministry of the Environment 'Heatstroke Prevention Information Site' https://www.wbgt.env.go.jp/wbgt.php

■ Insights on the Effectiveness of External Cooling in Heatstroke Prevention

An increase in body temperature in a hot environment is considered a factor that elevates the risk of heatstroke. As a means to suppress such temperature rise, 'external cooling,' which cools from the body surface using ice or cold water, has been reported as effective in many studies.

Moreover, in studies conducted in environments with a WBGT of 31°C or higher, it has been confirmed that cooling suppresses the rise in core body temperature and heart rate, indicating that it leads to the suppression of body temperature elevation.

Furthermore, in practical demonstrations in educational settings, implementing palm cooling showed a tendency to reduce the occurrence of suspected heatstroke even in hot environments.

In addition, external cooling has the characteristic of immediately lowering skin temperature, making it an effective measure in heatstroke countermeasures where rapid body temperature reduction is required.

▼ Sources
- Sports Nutrition Association of Japan (SNDJ) 'The Importance of Conditioning and Cooling in Hot Environments'
https://sndj-web.jp/news/002360.php
- J-STAGE 'The Effect of Cooling on Physiological Responses in Hot Environments' https://www.jstage.jst.go.jp/article/juoeh/27/1/27_KJ00003570248/_article/-char/ja/
- CiNii Research 'Study on the Effect of Palm Cooling in Hot Environments' https://cir.nii.ac.jp/crid/1050303932801785472
- Weathernews 'The Importance of Cooling in Heatstroke Countermeasures' https://weathernews.jp/s/topics/202107/300135/

■ About the 'Ice Pack' Series

The 'Ice Pack' series is a flagship product of Peacock Vacuum Bottle that has been a massive hit since its launch in 2021. It solves the conventional problem of ice bags where the coldness does not last, enabling cooling anytime and anywhere. It has won the Good Design Award and acquired Phase Free Certification. It is introduced in numerous media, including TV, as a product that can be used for the increasingly necessary heatstroke countermeasures year by year, as well as during disasters.

While similar products have been on the market since last year, thanks to the trust in the quality and cold retention power produced by a pioneer and thermos manufacturer, it continues to be chosen as the 'original cold-retaining ice bag.'

About the cold retention power of the Ice Pack Silicone Ice Bag Type [ABB-L30] (Example)

The graph on the left shows that when the ice bag is kept in a thermos-structured cold-keeping holder in an environment of about 40°C, the temperature inside the ice bag is maintained at about 0°C even after 24 hours.

In reality, the cold retention effect will be shorter because the ice bag is taken in and out of the holder for use, but the [ABB-L30], which corresponds to the L size in the series, is useful for long-time activities in the heat.

Other product numbers also have different maximum cold retention times, but they keep the ice bag cold for a long time with the cold retention power that utilizes the vacuum insulation technology cultivated so far.