Buttonhole

Definition and Overview

A buttonhole is an opening made in the front placket, cuffs, collar, or cuffs to fasten the opening of a garment by passing a button through it. The cut edge of the fabric is reinforced around the opening with overcasting or similar stitching so it will not fray. It is also called a button hole.

A buttonhole is not the button itself, but a specification on the side that receives the button. The “holes” and “shanks” on two-hole buttons and shank buttons refer to the structure of the button side and are distinguished from a buttonhole.

Shape and Construction

Common shapes include a straight-ended buttonhole with both ends finished straight, and an eyelet buttonhole with one end rounded. Straight-ended buttonholes are used for shirts and blouses, while eyelet buttonholes may be used for thick outerwear and tailored garments.

In addition to machine buttonhole stitching, hand-overcasting methods are also used. If the textile is thin, easily stretches, or frays easily, the surrounding area is reinforced with fusible interlining or stay tape to prevent stretching and distortion of the opening.

• Straight-ended buttonhole: A buttonhole finished straight at both ends.
• Eyelet buttonhole: A buttonhole with one end rounded to make it easier to insert and remove the button.
• Buttonhole overcasting: Stitching that prevents fraying at the cut edge.

How Size Is Specified

Buttonholes are generally specified by the finished length of the opening in mm. It is important to make the length so the button passes through smoothly and is not more likely than necessary to come undone when fastened. The actual length is determined by considering the button’s outside diameter, thickness, shank height, and the thickness and stretch of the textile used.

Ligne is mainly a unit used to indicate button diameter, and is not a unit for indicating the length of the buttonhole itself. In specifications, the button size and buttonhole length are listed separately, and the fit is checked with an actual sample before mass production.

Main Applications

Buttonholes are used on garments that fasten with buttons, such as shirts, blouses, cardigans, jackets, coats, pants, skirts, and dresses. The appropriate reinforcement and sewing specification differ between areas that use small buttons, such as cuffs and collars, and areas that take repeated stress, such as front openings.

Even decorative buttons require buttonholes if they are to function as openings. On the other hand, buttonholes are not always provided in constructions that sew on decorative buttons only, or in constructions that fasten with snaps or zippers.

Handling and Precautions

When unfastening a button, do not pull on the textile strongly; guide the button along the opening. If fraying at the edge, broken stitching thread, or stretching occurs, repairing it promptly helps prevent the tear from spreading. This is especially important for knits and loosely woven fabrics, which are more likely to stretch around the opening.

Whether washing, dry cleaning, and ironing are allowed, and under what conditions, depends on the care label for the entire garment and the material of the button being used. Pressing a hot iron directly on the button or around the buttonhole may cause the button to crack, deform, discolor, or cause the fusible interlining to peel off.

Frequently Asked Questions

How is the length of a buttonhole determined?

It is determined based on the button’s outside diameter, taking into account the button’s thickness, whether it has a shank, and the thickness and stretch of the textile. Even with the same diameter, thick buttons or shank buttons require a different length for passage. In mass production, a trial sample is always made with the textile and button combination, and the fastening performance is checked.

What is the difference between a buttonhole, an eyelet buttonhole, and a straight-ended buttonhole?

Buttonhole is the general name for openings that pass a button through. Eyelet buttonhole and straight-ended buttonhole indicate differences in the construction shape. An eyelet buttonhole has rounded ends, while a straight-ended buttonhole is basically straight. They are used according to the thickness of the textile, the garment’s applications, and the design.