Function: The adhesive bandage secures the injured and exposed part of the human body. It also protects wound scab from atmospheric bacteria, friction,  impairment, and dust. Therefore, the healing phenomenon in the human body is less disrupted. Some of the dressings have resistant properties against disease-causing microorganisms. An additive purpose is to grip together the two edges of the wound in the skin to make the healing quicker.

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Courtesy: How Its Made

Material: The adhesive film is normally a woven fabric, plastic like PVC or polyethylene. The adhesive strip is normally an acrylate, for example epoxy diacrylates and methacrylates. These are also referred as vinyl resins.
The absorbent pad is usually produced from cotton, and there is at time a scant, spacious-polymer covering over the pad, to avoid it from sticking to the wound. The pad is also medically treated with an antiseptic agent. In some strips, the pad is formed of a water-soaking gel. This is particularly normal in dressings utilized on blisters, as the gel behaves and acts as a cushion.

Caution: Many folks have allergies to many of these materials, specially latex and few other adhesives. Therefore FDA recommends latex free materials to be used for this purpose.