Orthotic insoles, including those made of polyurethane (PU), are designed with multiple layers to provide optimal support and comfort. The structural composition typically includes the following components:
1. Top Cover
This is the uppermost layer of the insole that comes in direct contact with the foot. It is usually made of a soft and breathable material like fabric or foam. The top cover helps to enhance comfort, reduce friction, and prevent moisture buildup.
2. Cushioning Layer
The next layer is responsible for providing cushioning and shock absorption. In PU insoles, this layer is often made of a PU foam material. PU foam is known for its excellent cushioning properties, as it can effectively absorb impact forces and distribute pressure evenly across the foot.
3. Arch Support
Many orthotic insoles, including PU insoles, feature an arch support component. This part is designed to provide additional support to the arch of the foot, helping to maintain proper alignment and reduce excessive pronation or supination. The arch support is typically made of a firmer material like thermoplastic or EVA (ethylene-vinyl acetate).
4. Heel Cup
The heel cup is a deep, contoured area at the rear of the insole that cradles the heel. It helps to stabilize the foot and prevent excessive movement, providing support and alignment to the heel and ankle. In PU insoles, the heel cup is often made of a firm PU material to provide structural integrity and stability.
5. Base Layer
The base layer forms the bottom of the insole and provides stability and durability. It is usually made of a rigid or semi-rigid material like thermoplastic or PU. This layer helps to maintain the shape and structure of the insole and prevents excessive flexing or deformation.
By combining these different layers, PU insoles offer a balance of cushioning, support, and stability, making them comfortable for prolonged use and various activities. They can help alleviate foot fatigue, reduce discomfort, and provide overall foot support.
Related product links: https://www.aideastep.com/product/semi-rigid-flexible-support-orthotic-insole/.