Topstitch Thread

Definition and Overview

Stitch thread is thread used for topstitching, visible on the face side. In addition to the function of joining pieces, it shows the seam line, thread color, thickness, and sheen as part of the product design. It is used for contrast stitching on denim, and for edge stitching on jackets and bags.

Ordinary sewing thread can also sew stitches, but stitch thread usually refers to thread with thickness and a surface feel that make it easy to create presence. However, the scope of the term varies by maker and by workplace, and thick sewing thread may also be used for stitching.

Materials and Twist / Structure

Materials include polyester, cotton, nylon, and silk, and are selected according to the desired appearance and use environment. Polyester may be chosen for applications that emphasize strength and ease of handling, while cotton may be chosen for applications that aim to create a natural look.

Thread structures include spun thread made by twisting short fibers together, filament thread made from continuous long fibers, and core-spun thread with fibers covering a core thread. The direction and amount of twist, and the thread structure, affect sheen, fuzz, resistance to friction, and ease of handling during sewing.

• For thicker thread, check compatibility with the needle hole and thread path.
• The strength of the sheen affects the contrast with the textile and the appearance of the seam line.
• If the stretch difference between the textile and the thread is large, it may cause seam puckering or thread breakage.

How Thickness Is Expressed

The thickness of stitch thread is shown by count, denier, tex, or nominal count. The way count is expressed differs by thread type; in general, for cotton count, the smaller the number, the thicker the thread, but numbers cannot be compared across different systems simply by the value alone.

Nominal count is a thickness guide used for sewing thread, but the actual thickness and strength vary depending on the material and structure. In specifications, it is important to list not only the count or nominal count, but also the material, color, and, if necessary, the thread structure, and to confirm with an actual sample.

Main Applications

Typical applications include the side seams, yokes, and pockets of denim, reinforcement stitching for workwear, and edge stitching that secures the edges of shirts and jackets. It is also used in bags and leather goods to emphasize the seam line as an outline.

Depending on the application, the required properties of the same stitch thread differ. For garments that are washed frequently or subject to much friction, attention must be paid to color fading and abrasion. Also, in thick layered sections, the needle’s ability to penetrate the textile and the feed performance of the sewing machine affect the finish.

How to Choose and Sewing Considerations

Select the material and thickness according to the textile thickness, weave or knit density, number of stitches, and product washing conditions. For prominent stitching, check not only the contrast with the textile color, but also color difference and sheen difference after washing through trial sewing.

When using thick thread, adjust the needle size, needle hole size, upper thread tension, and combination with the lower thread. If the thread is too thick for the needle hole, thread breakage, skipped stitches, and puckering become more likely. Before mass production, carry out sewing tests under conditions with the actual textile layered as it will be used.

Stitch thread is mainly thread intended for visual appearance on the face side, while buttonhole twist is thread suitable for buttonhole stitching, and button sewing thread is thread for sewing on buttons. All of these can be thick, but the strength, twist, and sewing suitability appropriate to the application differ.

FAQ