Achieving the “Overwhelmingly Cool Umbrella” – What’s Amazing About Estaa’s “Dannetsu Parasol”?

As the summers in Japan become increasingly severe year by year, the demand for heat prevention items is expanding. Alongside cool towels and handheld fans, the effectiveness of umbrellas is being re-evaluated, and the number of users, regardless of gender, is on the rise.

Thanks to recent technological innovations, the functions of umbrellas are continuously improving. The umbrella, “Dannetsu Parasol,” developed by MOONBAT Corporation, is one such example. Since starting test sales in 2021, it has undergone numerous advancements.

What kind of features does this item possess? We spoke with Suzuki from the company about the characteristics and functionality of the Dannetsu Parasol.

What is the Difference Between “Shanetsu” & “Dannetsu”?

The Dannetsu Parasol is an umbrella developed with a focus on “coolness.” It has both heat shielding and insulation functions, claiming to lower the perceived temperature by about 2 degrees compared to umbrellas made with first-class light-blocking fabric (which has a light-blocking rate of 99.99% or higher). So, what exactly is the difference between “Shanetsu” and “Dannetsu”?

“Shanetsu means ‘the ability to block the heat contained in direct sunlight.’ While some heat can be prevented with just light-blocking fabric, the use of heat shield agents increases the effectiveness of blocking heat.

"However, there is a principle of radiant heat (輻射熱) that pulls heat from the outside to the inside. Therefore, if the umbrella is used for an extended period, the surface temperature rises, gradually increasing the temperature inside the umbrella due to radiant heat. The heat shielding effect alone has limitations in preventing radiant heat from penetrating inside the umbrella.

"Wishing to resolve this, we focused on 'Dannetsu.' Insulation is often utilized in construction materials, creating an air layer between the inside and outside walls, which retains heat and slows down the transfer of heat to the interior. The application of this principle to umbrellas resulted in the Dannetsu Parasol.”

The Dannetsu Parasol ensures that an air layer is created by sandwiching an aluminum insulation sheet between the outer and inner fabrics, making it difficult for heat to transfer inward. To facilitate air circulation, a light-blocking coating has intentionally not been applied. However, because of its three-layer structure of outer fabric, aluminum sheet, and inner fabric, it offers functionality comparable to products that claim 100% UV cut.

Thanks to both heat shielding and insulation features, the Dannetsu Parasol achieves overwhelming coolness.

Introducing the Foldable “Honeycomb Dannetsu Parasol”

While the Dannetsu Parasol was initially offered only as a long umbrella, the demand for foldable umbrellas is higher in the market. Therefore, in 2024, we will launch the foldable “Honeycomb Dannetsu Parasol.” Developing new technology was necessary to enable foldability.

“Due to the nature of the aluminum sheet material, it tends to be thick, making it difficult to fold. Additionally, there were challenges in proper sewing, making it an unsuitable material for foldable umbrellas.

"Therefore, we developed a honeycomb-structured aluminum sheet. This sheet has a matte honeycomb silver print (a pattern arranged with hexagons) over a fabric with light-blocking coating, creating a fabric that easily blocks sunlight and allows heat to escape, thus achieving both light-blocking and heat-shielding functions.”

Even with a change in the technology used, maintaining 100% light-blocking and UV shielding rates is something that only a company with high technological capabilities can achieve.

Three Years Required to Achieve Innovative “Insulation” Functionality

During development, the challenge arose that while the ideal functionality could be achieved, mass production proved difficult, often preventing product commercialization. Given that it was an unprecedented development, it reportedly took about three years from the initial concept until the product was completed.

Moreover, the commitment to the insulating parasol extends beyond functionality. Efforts have been made to ensure that the design and color of the umbrella’s interior also give a visual sense of “coolness.”

However, even if a product with excellent functionality and design is created, if its price diverges significantly from typical sun umbrellas on the market, the number of consumers willing to purchase it will likely be limited. Suzuki states, “I want more people to experience the coolness, so we are working to minimize the retail price as much as possible.”

“Since the insulating parasol uses more layered fabric than a standard sunshade, material costs rise, and due to the special frame design and sewing difficulties, insulation parasols tend to be more expensive. While there are still hurdles to price standardization, I believe there is room for improvement and would like to continue reviewing this in the future.”

Sun Umbrellas Are Essential for Enjoying a Comfortable Summer

Previously, many people purchased sun umbrellas mainly to prevent sunburn, but Suzuki notes that “the number of people buying them for heat protection and preventing makeup from melting due to sweat is increasing.”

“Sun umbrellas have traditionally been favored by relatively older individuals. However, I feel that recently even middle school and high school students have begun to use them. With the rise in extremely hot days, sun umbrellas seem to be becoming a necessity for all ages and genders.

"The insulating parasol is suitable for both sunny and rainy weather, making it a versatile item for year-round use. Especially under the intense summer sunlight, its effectiveness is greatly enhanced. I would love for more people to try it out to enjoy a slightly more comfortable summer.”

Moonbat is planning to continue developing new products to meet a diverse range of user requests. It will be interesting to see what items are born from this initiative.