There are many kinds of shoes: leather shoes, football shoes, labor insurance shoes, running shoes, basketball shoes, etc. With the improvement of people's living standards, shoes are endowed with various functions: fashionable appearance, shock absorption, wear resistance, lightness, sports protection, etc. Different materials are used to make various parts of the shoes, which can reduce the cost while meeting the design requirements.
Tongues, uppers of sports shoes
The tongue and upper of sports shoes mainly play the role of ventilation and protection. Usage the polyurethane soft foam with lower density and good air permeability, and compound it with the fabric to achieve low weight and low cost
Good air permicity
Good light stability
The plastic parts for shoe upper decoration made of TPU have bright colors and good processability, and can make shoe upper accessories of various shapes and colors.
Midsole of sports shoes
Uniformed particle size
Good foaming effect and high yield
The midsole of sports shoes refers to the interlayer between the outsole and the shoe body, with a thickness of 1-2 cm. The main function is to absorb shock to reduce the impact of vibration on the knees and arches during running and jumping. The application of TPU in the midsole has increased significantly in recent years, such as foamed TPU (ETPU) and TPU air cushion: foamed TPU is foamed by supercritical carbon dioxide, and then formed by high-temperature steam heat pressing. Developed by BASF, Adidas was first applied to running shoes, which is characterized by very high resilience.
Good dynamic properties (rebound, energy- absorption)
The insole is made of polyurethane high-density sponge, usually high-rebound or slow-rebound sponge: the insole made of high-rebound sponge has good resilience and is suitable for running shoes; the insole made of slow-rebound sponge has an energy-absorbing effect, which can reduce long-distance walking and mountaineering fatigue.
High processing efficiency
The outsole of sports shoes needs to face the severe friction caused by high impulse in the process of high-speed movement, which requires the material to have good wear resistance and anti-slip performance on wet ground. The outsole made of TPU has excellent wear resistance and can be made into various colors, adding more possibilities to designers. The modified TPU can also have anti-slip properties
Hot-melt TPU adhesive for shoe sole
Safety and environmental protection
The various parts of the shoe are usually joined together using stitching or adhesive. The bonding process has high efficiency. With the improvement of environmental protection requirements, the use of solvent glue is less and less. Hot-melt TPU adhesive is easy to use, has no VOC, and has strong bonding. The amount of hot-melt TPU used in shoe bonding is increasing.