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Film made with DURANEX® PBT deployed in portable Instant Toilet with deodorizing disposal bag

Horiaki Co., Ltd.



    As awareness about preparedness for emergencies and disasters increases, there is an urgent need to have emergency-use toilets on hand for when disasters occur. The portable Instant Toilet developed and sold by packaging materials company Horiaki Co., Ltd. has caught the attention of many local governments and other related agencies because it eliminates concerns about additional disasters caused by odors at shelters and evacuation zones.
    In addition to being easy to assemble, this portable toilet by Horiaki Co., Ltd. also thoroughly blocks the sources of odors. This is made possible by the toilet’s deodorization bag made with Polyplastics DURANEX® PBT (polybutylene terephthalate).


Development of the Instant Toilet

    The Instant Toilet was originally developed to overcome the shortage of toilets when the Kumano Kodo pilgrimage trails in the south of Japan’s Kansai region were registered as a World Heritage site. Not only are new buildings not allowed on World Heritage sites, but it is not even permissible to dig a single hole. It was impossible to consider building new permanent restroom facilities on site, so portable toilets were needed. These toilets would have to be easy to assemble in the necessary places and to carry away after use.
    For these reasons, development of the toilet proceeded with focus on the keywords easy, lightweight, hygienic, sturdy, and deodorizing. Portable toilets made of cardboard already existed, but the problem was that they took time to assemble. The Instant Toilet overcame this with a two-piece design consisting of a base and a seat, making it easy to assemble. Its base made of cardboard with a polypropylene honeycomb structure connects easily with the seat made of the same material. In addition to having a simple structure, using cardboard made from polypropylene (plastic) as the material made the toilet lightweight at a mere 750 grams. While the structure may be both lightweight and easy to assemble, it is also sturdy enough to support up to 200 kg of body weight. Since the toilet is made of plastic it can also be washed with water and kept in a clean, hygienic state.
    The last major issue is odor. Since it takes time, manpower, and cost for local governments and communities to collect sewage, the toilet had to do more than just deodorize. It needed to be able to completely block odors so that none escape at all. For a portable toilet such as this, odors simply cannot be allowed to escape. More than just a requirement, this can be considered an essential characteristic. Consequently, attention turned to Polyplastics DURANEX.



Disposal bag made with PBT

    The disposal bag made with PBT is what made the Instant Toilet possible. Bags composed of film made with PBT are produced using single-layer blow molding, but crystalline resin is typically considered incompatible with blow molding. PBT is also particularly difficult to work with in blow molding because its viscosity decreases when melted. Kansai Kagaku Kogyo which produces and sells various films for packaging is currently the only company that manufactures these bags.
    Development of film made with PBT originated with sterilization bags for medical use. It began with requests from users to try producing sterilization bags that could withstand temperatures of 170°C for 20 minutes. This requirement ultimately led to Polyplastics DURANEX. After the bags were developed, film made with PBT started capturing attention for its odor-blocking properties as well as its heat resistance.

    The first expanded usage application of the bags was as carry-out bags for kimchee. Chosen by kimchee stores that pull kimchee from pickling barrels and sell it by weight, the bags were sold as odor-blocking bags which allow no odor to escape. Subsequently, the odor-blocking properties of the bags were deployed for sanitation in places such as nursing care facilities, which led to selection of the bags for the Instant Toilet.




Instant Toilet disposal kit and personal bags

    The Instant Toilet is comprised of the plastic cardboard main unit described at the beginning of this article, an Instant Tent, and the Instant Toilet disposal kit made up of the PBT bag and other parts of the kit. (Parts of the disposal kit and how to use it are as shown in the pictures)
    Horiaki sells these disposal kits as Personal Bags for Instant Toilet. Large personal bags are for outdoor use, containing both the portable toilet and a disposal kit, while small personal bags are made for use with a conventional toilet and therefore do not come with a portable toilet.



Portable toilets when disasters occur

    The Instant Toilet with its superior functionality is entering more widespread use as a portable toilet at shelters and evacuation zones. It is also being increasingly utilized during emergencies by local governments and at apartment complexes and buildings.
    When residents are suddenly unable to use water due to disasters or for any other reason, toilets might become unusable if buildings and apartment complexes face water shutoffs or usage restrictions. This could cause foul odors on entire floors of buildings, and unsanitary waste might pile up in the garbage collection area. Toilet-related problems such as these happen in many different places.
    Outer film bags made with DURANEX offer tremendous advantages in these types of situations. Portable toilets such as the Instant Toilet that can be used with peace of mind are likely to become an essential part of safety in everyday life.



    Film made with DURANEX can block odors and has heat resistance to withstand temperatures of 170°C. Despite having both these characteristics, it has mostly been deployed only for odor-blocking applications to this point. Going forward, Polyplastics aims to deploy this film for applications that require both heat resistance and odor blocking. We hope it becomes an essential material in functional heat-resistant bags and film that are all around you in everyday life.

【Related information】DURANEX® PBT Products Information