U.S. patent application 20190219320 (applicant Softbox Systems Ltd., Long Crendon, Great Britain):
"The present invention relates to the field of the transportation and storage of goods and to a passive temperature control system for such a transport and storage containers. The present invention seeks to provide a system that can enable goods to be securely and reliably transported and stored for limited periods within specified temperature ranges. Pharmaceuticals, proteins, biological samples and other temperature sensitive products, including food items, are regularly shipped in containers year round and are subjected to a wide range of temperatures. Though they are shipped in insulated containers and/or climate controlled environments, the temperature stability of the shipping containers can be significantly improved by utilising suitable phase change materials in an ordered fashion. The present invention provides a simple solution to the maintenance of temperature profiles for the transport and storage of temperature sensitive products."