Terra Innovation Centre

Work BootAnatomy

Terra work boots use a combination of full grain leathers with sealed seams, ballistic (or high denier) nylon, rustproof eyelets and high tensile stitching. The uppers are then complemented with insulation layers or a waterproof membrane suited to the purpose of the footwear.

The Upper

The upper of a work boot is the top layer that covers and supports the foot, comprised of leather, nylon, insulation and waterproofing, as well as the hardware and lacing systems.

Terra Elite
Terra Elite

Terra Leathers

Leather is a natural material chosen primarily for uppers due to its natural breathability, waterproofing properties and abrasion resistance. It’s durable and very versatile. All Terra uppers use sealed seams to improve waterproofing; however, the water resistance of Terra leathers starts at a more fundamental level. During leather selection, all prospective leathers undergo a flex test. The test, using a Maser flex machine, takes a section of leather and flexes it continually. One side of the leather is exposed to water while the other side is exposed to a mild electrical current. The machine flexes the leather until the water penetrates, contacting the electrical current and closing the circuit.

Terra Elite

All Terra leathers must pass a 15,000 flex test in order to pass baseline standards; however the majority of our leathers pass or exceed the standard by more than 30,000 flexes prior to water penetration.

Nylon Fabrics & Linings

Synthetic nylon fabrics are employed in the construction of a boot upper to increase abrasion resistance, lower overall weight and improve chemical resistance. Nylon fibres are woven together in a particular pattern to create a durable, redundant layer that resists snags and tears. The end result is a strong defensive layer that protects against sharp edges, protrusions and other hazardous environments where leather could be compromised. Synthetic upper materials like nylon also have the added benefit of being easier to clean and maintain, as well as offering superior protection from chemical hazards, especially when paired with a Gore-Tex® waterproof membrane. The strongest and most successful ballistic nylon configuration is a double weave 1050 denier nylon. Denier is a measurement of the weight of the fibres, not the strength. The key to the strength is in the weave pattern.

Linings protect the upper and the inside of the boot from being damaged by excessive wear or moisture damage, including mildew and odour. Insulation keeps feet comfortable and controls environmental factors.

Terra footwear incorporating Gore-Tex® waterproof membranes provide world class, guaranteed waterproofing. Gore-Tex® membranes contain over 9 billion microscopic pores per square inch. These pores are 20,000 times smaller than a water droplet, but 700 times larger than a water vapour molecule, which makes the GORE-TEX® membrane durably waterproof, while allowing perspiration to escape from the inside. An oleophobic, or oil repelling, substance is integrated into the membrane, preventing the penetration of body oils and insect repellent that could otherwise affect the membrane.

Nylon Fabric
The Midsole

The Midsole.

The midsole of a work boot serves as the primary shock absorbing layer. Situated between the upper (with insole) and the outsole, TERRA midsoles are made of lighter, less dense materials than the outsole. Impact and weight are distributed evenly to improve boot stability and comfort.

Materials used in midsole construction vary depending on application.

Polyurethane [PU] midsoles are injected in varying densities and offer a range of comfort and support potential. The PU material is injected in a liquid form as part of a multi stage process, before being bonded to the boot upper.

Ethylene-Vinyl Acetate [EVA], is attached or cemented to the upper and outsole of a shoe or boot. It is a mouldable and versatile material which is very lightweight offering much in the way of comfort, but much less in terms of durability than other options. EVA midsoles are most commonly found on athletic footwear or lighter weight shoes.

The Outsole.

The outsole is the foundation of the boot, the layer that comes in direct contact with the ground. Different soling materials provide varying benefits to traction and durability. As such, the conditions and intended use of the footwear play a vital role in selection of the soling materials to be used.

Outsole tread design also plays an important role in mitigating several of these factors. Finer edges and higher surface area will greatly improve slip resistance. Harder materials and more defined tread patterns will provide superior abrasion resistance. Depending on the application, the dispersion and ejection of foreign objects from the outsole rely almost entirely on the pattern of the tread.

Polyurethane [PU] is a lightweight soling material injected in a liquid form directly onto the upper of the boot. PU outsoles offer excellent abrasion resistance, slip resistance and flexibility and chemical resistance.

Thermoplastic Urethane [TPU] has many unique properties as a soling material. Its high abrasion resistance allows it to be used in much thinner layers than other materials. This creates more flexible, comfortable outsoles by allowing more room for lighter weight midsole materials. Improved mould definition permits the creation of more intricate outsole designs with sharper edges, providing much better slip resistance. TPU also remains pliable in cold temperatures, making it suitable for winter conditions.

Rubber is a natural material used in a variety of soling applications. It is the most versatile soling material with a higher melting temperature compared to PU/TPU, it also stays flexible in cold temperatures. Nitrile rubber has an additive in the soling material which vastly improves heat resistance (Up to 300 degrees C) and provides exceptional oil and acid resistance.

Vibram® Fire & Ice is a rubber outsole developed by Vibram® for use on TERRA boots specifically designed to handle extreme temperature changes. The material stays flexible and slip resistant under extreme cold or high heat, with an improved melting point and retaining its traction. Vibram® rubbers are hard enough to be very abrasion resistant, but flexible and soft enough to offer excellent slip resistance.

The Outsole
TERRA FOOTBED

TERRA FOOTBED®

The comfort and support layer upon which the foot rests in the boot.

A FOOTBED® improves overall comfort and health of the wearer by keeping the foot stable and supported. Providing additional shock absorption and distributing impact across a larger surface area, the FOOTBED® will reduce overall fatigue.

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