Adhesive bandage

An adhesive bandage, also called a sticking plaster (or simply plaster) in British English, is a small medical dressing used for injuries not serious enough to require a full-size bandage. They are also known by the genericized trademarks Band-Aid (as "band-aid" or "band aid" in the US) or Elastoplast (in the UK).

The adhesive bandage protects the wound and scab from friction, bacteria, damage, and dirt. Thus, the healing process of the body is less disturbed. Some of the dressings have antiseptic properties. An additional function is to hold the two cut ends of the skin together to make the healing process faster.

An adhesive bandage is a small, flexible sheet of material which is sticky on one side, with a smaller, non-sticky, absorbent pad stuck to the sticky side. The pad is placed against the wound, and overlapping edges of the sticky material are smoothed down so they stick to the surrounding skin. Adhesive bandages are generally packaged in a sealed, sterile bag, with a backing covering the sticky side; the backing is removed as the bandage is applied. They come in a variety of sizes and shapes.

The backing and bag are often made of coated paper, but may be made of plastic.

The adhesive sheet is usually a woven fabric, plastic (PVC, polyethylene or polyurethane), or latex strip. It may or may not be waterproof; if it is airtight, the bandaid is an occlusive dressing. The adhesive is commonly an acrylate, including methacrylates and epoxy diacrylates (which are also known as vinyl resins).

The absorbent pad is often made of cotton, and there is sometimes a thin, porous-polymer coating over the pad, to keep it from sticking to the wound. The pad may also be medicated with an antiseptic solution. In some bandages, the pad is made of a water-absorbing hydrogel. This is especially common in dressings used on blisters, as the gel acts as a cushion.

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