What is LIMEX

LIMEX is a new material mainly made from limestone
that can become an alternative to plastic and paper.

Limestone is a sustainable raw material, with abundant reserves all over the world.
It is 100% self-sufficient even in Japan and said to be almost inexhaustible.
We believe that this sustainable material can save the world.

Earth, a Planet of Stones.

Limestone, which is the raw material of LIMEX is a resource that can be self-sufficient even in Japan, where resources are scarce. The estimated recoverable years of limestone continue to grow, with 24 billion tons of resources reserved in Japan alone, and limestone is said to be a resource with a very low risk of depletion compared to oil, water, and forest resources. Since paper alternative products can be manufactured with almost no use of water or forest, it could be manufactured in many places. Also, by promoting local production for local consumption, a compact supply chain can be constructed, which could reduce impact on the environment. Because it is a resource that is abundant everywhere, we believe it can save the world.

Superiority of Limestone.

In the raw material procurement process, petroleum-based resin are manufactured by fractional distillation of crude oil and naphtha and polymerizing the extracted monomers. The impact of climate change is caused by the consumption of energy through the heating process. However, calcium carbonate, the main raw material of LIMEX, is produced by crushing limestone. Due to this difference in process, Limestone can reduce CO2 emissions by about 50 times compared to petroleum-based resins.

Mining and processing of limestone is easier than petroleum and metal. Because it is abundant all over the world, it has excellent supply stability and is inexpensive. Products such as plastics and rubber deteriorate due to environmental factors such as exposure to sunlight, but the physical characteristics of limestone are more stable. It is a resource that is not easily affected by environmental factors.

International Patents for LIMEX.

In 2014, LIMEX was patented in Japan. The basic patent has been submitted in over 40 countries worldwide.
LIMEX has been introduced at international conferences, such as COP and G20. Moreover, it is registered in the sustainable technology dissemination platform of UNIDO (United Nations Industrial Development Organization) as an excellent technology of Japan. We will export the LIMEX technology and brand as a new Japanese technology, so that LIMEX becomes a material used commonly in the world.

Flexible molding using LIMEX.

LIMEX is suitable for diverse molding methods including injection molding, extrusion molding, vacuum molding, and blow molding. Though LIMEX is a composite material, it does not require custom equipment and can be processed using traditional methods and machinery. LIMEX is used by more than 6,000 companies and municipalities for a variety of purposes. (As of June 2021)

LIMEX Manufacturing Process.

LIMEX is an advanced material produced from calcium carbonate (CaCO3), which is derived from limestone, and a small amount of polymeric resin added as a binder. These materials are heated and kneaded in a twin screw extruder, creating a molten, homogeneous composite containing over 50% calcium carbonate by body weight. Next, the composite is heated and pressurized treated under LIMEX’s proprietary manufacturing process, resulting in material properties ideal for post-processing.

LIMEX pellet is manufactured by pelletizing, the process of molding the molten composite into the shape of a pellet. LIMEX pellet is also manufactured by pelletizing edge waste produced through manufacturing and printing process or used LIMEX sheets collected from consumers. Since the amount of petroleum-based resin contained in conventional plastic products can be reduced, LIMEX is used as a material to "reduce plastic".

LIMEX sheet is manufactured by T-die sheet extrusion of the molten composite, and stretching process controlling a porous structure in order to create whiteness and lightness. Next, specific coating agent is applied onto the surface of LIMEX sheet depending on its application, enhancing surface properties for various kinds of printing process. Stone paper and LIMEX Sheet are different products.

Appropriate recycling of LIMEX.

Compared to polypropylene, which is a petroleum-based resin, LIMEX has been proved to be a material with a lower rate of deterioration of physical properties and higher recycling efficiency than PP in terms of melt flow rate (MFR) *1 and Charpy impact strength*2. In addition, when we verified the sorting of LIMEX and PP with an optical sorter, we were able to detect them as different substances and prove that they can be derived. the collected post-consumer LIMEX products (paper alternative products) will be upcycled into plastic alternative products. TBM will promote the resource recycling of LIMEX by cooperating with domestic and overseas partner companies.*1 MFR: A numerical value that represents the fluidity of a thermoplastic resin when it is melted
*2 Charpy impact strength: Impact test to evaluate the energy required to break the test piece and the toughness of the test piece


TBM is committed to leveraging our impact on progressing towards the SDGs, especially through our product, LIMEX.
We and many companies like us are determined to achieve these goals. Centered around Goal 12 ‘Responsible consumption and production’, we identified 8 key goals that we aspire to contribute towards: Goal 6 ‘Clean water and sanitation’, Goal 13 ‘Climate action’, Goal 14 ‘Life below water’, Goal 15 ‘Life on land’, Goal 8 ‘Decent work and economic growth’, Goal 9 ‘Creation of industries’, and Goal 17 ‘Partnerships for the goals‘.
To determine these 8 focal goals, we focused on two key perspectives to clarify the relationship between our business, specifically our value chain, and the SDGs. They are: (i) the impacts that TBM and its value chain can have on the SDGs and (ii) the impacts that the trends surrounding the SDGs have on TBM and its value chain. As a result of this process, we identified the 8 goals as our focal goals.

The Future of LIMEX.

In recent years, the international treaty "Basel Convention", which regulates the definition of hazardous waste and import / export, has increased the need for local resource recycling. In Europe, the European Commission has set a goal of eliminating disposable plastic packaging in the region by 2030. In Japan, the "Plastic Resource Recycling Strategy" was announced based on the “Basic Act on Establishing a Recycling Society”. The goal is to double the recycling of plastics by 2030, make 100% effective use of used plastics by 2035, and new resource recycling models are being created through partnerships between local governments, companies, and universities.

TBM sees these changes as an opportunity. To meet the growing needs for recycled materials and plastic alternative materials throughout the world, TBM will promote LIMEX and CirculeX, a material made from used LIMEX and plastics.

Issuance of JSA standard for LIMEX.

The JSA standard (JSA-S1008), which aims to clarify the definition of "inorganic / organic composite materials mainly composed of inorganic substances" including LIMEX was published by the Japanese Standards Association on April 19, 2021. This JSA standard aims to promote market expansion and quality stabilization, and lead to fair transactions of "inorganic / organic composite materials mainly composed of inorganic substances".
JSA-S1008 regulates the test methods for "Measurement of mass fraction with respect to total amount of inorganic substances", "Confirmation of presence / absence of thermoplastic resin" and "Types and mass fractions of the main constituent materials and the second material" for materials in which the main constituent material is a single inorganic substance and the total amount of inorganic substances exceeds 50% by body weight.

We make the most use of resources and regenerate its value sustainably.
A circular economy is the future we aim for.