Hook And Loop

Definition and Overview

Hook and loop is a fastening material made up of a hook surface with tiny hooked pile on one side and a loop surface with looped pile on the other. When both sides are pressed together, the hooks catch on the loops, and it opens by peeling them apart.

Structure and Differences from Zippers

Typical hook and loop consists of the hook surface, the loop surface, a base fabric supporting each, and selvage edges for sewing. Depending on the application, there are also double-sided types that combine hooks and loops on one side, and types with adhesive on the back.

Hook and loop does not have teeth, sliders, top stops or bottom stops, or openings like coil zippers or metal zippers. Rather than choosing opening performance by tooth size or zipper length, specifications are considered based on the type of surface, width, overlap length, and holding power.

Types and Specifications

The hook surface has high holding power, but it can feel stiff and easily catch, while the loop surface is soft and is often used on the garment side. Depending on pile length, density, base fabric thickness, and flexibility, the feel when putting on and taking off, fastening strength, and appearance will change.

Tape-style products are selected by width and required length. When fastening the entire opening, set the overlap length by considering the fastening area, seam allowance, and edge finishing. Hardware cut into round or square shapes is also used depending on the application.

• For lightweight fabrics or areas that touch the skin, a soft loop surface or a thin specification is considered.
• In areas subject to strong loads, secure enough area by making the width wider or the overlap longer.
• Adhesive types are useful for temporary fixing or non-sewn applications, but compatibility with the material being attached should be checked in advance.

Main Applications

In apparel, it is used for front openings, cuffs, necklines, pocket openings, waist adjustment sections, and more. Compared with buttons or zippers, it is easier to operate with one hand and makes it easier to allow flexibility in the opening and closing position.

It is also used in sportswear, workwear, kidswear, bags, shoes, care and medical products, interior goods, and more. In areas that are opened and closed frequently, the balance between the required holding power and ease of use is important.

Selection and Handling Notes

In sewing, the direction of the hook surface and loop surface, the overlap position, and interference with seam allowance are clearly specified in the specification sheet. Because the tape edge can lift and cause peeling, confirm whether the shape allows stable sewing all the way to the edge. If the fabric is thin, also be careful about seam puckering and waviness.

If the hook surface is left open during washing, it may pick up lint and thread from other garments, which can reduce fastening strength. Before washing, it is generally secured to the corresponding loop surface, and any lint or foreign matter that adheres should be removed. Suitability for heat treatment, washing, and dry cleaning should be confirmed for each product specification.

Frequently Asked Questions

Where do you measure the length of hook and loop?

For tape-style hook and loop, the length is generally measured from one end of the tape to the other. When used for a garment opening, it is designed to include allowance needed for seam allowance and edge finishing. The length of the actual overlapping fastening area also affects holding power, so it must be checked separately.

Which side, the hook surface or the loop surface, should be attached on the outer side?

On the side that is likely to touch the skin or other garments, the softer loop surface is generally placed. However, the decision is made by prioritizing that the hook surface is not exposed during wear and that the edge does not catch when closed. It is important to confirm this with a prototype, including the opening and closing direction and the sewing process.

What should you do if hook and loop no longer fastens well?

If lint, pile, dust, or similar material gets packed into the hook surface, it will not catch the loop surface easily. Remove adhered material without damaging it, and check whether the hooks or loops are flattened, worn, or separated. If performance has declined through repeated use, replacement should be considered.