Buttonhole Elastic

Definition and Overview

Buttonhole elastic is elastic with buttonhole-shaped holes made at regular intervals near the center of the tape. By changing the position of the holes and fastening it to buttons, the circumference can be adjusted step by step even after sewing. It is mainly used for waist size adjustment.

Unlike flat elastic, which simply stretches to fit, its defining feature is that the adjustment amount can be controlled by the button fastening position. It is suitable for specifications that require accommodation for size changes and fit adjustment for each wearer.

Materials and Construction

In many cases, the surface is made with thread such as polyester, and elastic thread or polyurethane-based elastic thread that provides stretch is used inside or within the structure. Thickness, firmness, and stretch behavior vary depending on the type of surface thread, the thickness of the elastic thread, and the method used to reinforce the hole area.

Elastic tape construction includes woven elastic, knitted elastic, and braided elastic. In buttonhole elastic, woven tape structures are often seen because they stabilize the shape of the holes and reduce fraying at the ends, but the construction should be checked for each product.

• Woven elastic: made with a woven structure, and a construction that tends to have a relatively firm texture.
• Knitted elastic: made with a knitted structure, and a construction that tends to be soft and easy to stretch.
• Braided elastic: a construction made by braiding threads, used mainly for cord-like elastic.

How to Read Width and Stretch

Choose the width according to the dimensions of the belt section to be attached, the size of the button, and the required strength. It is important that the width and spacing of the holes match the diameter and thickness of the button used. If the button is too large, it can damage the hole; if it is too small, it can come off easily.

Stretch performance is expressed by the elongation rate, or how much longer it becomes when pulled compared with its length with no load. However, even with the same elongation rate, the initial firmness when pulling and the way it returns will differ. Make a sample at the actual use length and check the adjustable range and the pressure felt when worn.

Main Applications and How to Choose

The main applications are waist adjustment for children's clothing, maternity wear, uniforms, and similar items. It is generally used by threading it through the inside of the waist belt and fastening it to buttons placed on both sides or on one side. It is used for pants, skirts, dresses, and more.

When selecting it, check the tape width, hole spacing and shape, compatibility with the button, required adjustment range, and stretch strength. If it is sewn into the seam allowance, pay attention to the sewing position and stitching method to reduce damage to the elastic thread from the needle.

Handling and Precautions

Elastic materials may gradually lose their recovery from stretch due to repeated stretching during wear, heat, ultraviolet light, and exposure to sweat or detergent. For storage, avoid high temperature and humidity and direct sunlight, and do not leave it under strong stretch for long periods.

Durability during washing varies depending on the types of surface thread and elastic thread, as well as the sewing specification. Before mass production, check fastening and removal with the actual button, shrinkage and recovery after washing, and fraying or tearing around the holes, and handle it in accordance with the washing instructions for the product body.

Frequently Asked Questions

What is the difference between buttonhole elastic and flat elastic?

Flat elastic is an elastic tape that mainly fits through stretch force. Buttonhole elastic, on the other hand, has continuous holes for buttons, allowing dimensions to be adjusted step by step by changing the hole position used for fastening. Buttonhole elastic is suitable for waist size adjustment.

How do you choose a button to use with buttonhole elastic?

Choose a button with a size and thickness that passes through the elastic holes smoothly and is not easy to come off during wear. If the button is too large, it will place stress on the area around the hole; if it is too small, it will come off easily. It is necessary to combine the elastic and button to be used and check them by fastening and unfastening repeatedly.

Will buttonhole elastic stretch out completely after washing?

It does not necessarily stretch out completely immediately after washing, but the elastic gradually changes in performance due to heat, detergent, friction, and repeated stretching. Check the product's washing conditions, and in mass production evaluate recovery after washing tests, the condition of the holes, and the durability of the sewn parts.