Double-fold, Single-fold, And Four-fold

Definition and Overview

Double-fold, single-fold, and four-fold are names for shapes finished by folding ribbon, flat tape, synthetic leather tape, and similar materials lengthwise. They do not refer to the material type or to the manufacturing method itself, such as weaving, knitting, or braiding; they mainly describe how the edges are folded in.

Single-fold refers to a shape with one edge folded in, while double-fold refers to a shape with both edges folded inward. Four-fold generally refers to a construction with multiple layers in the cross section, such as folding tape with both edges folded and then folding it in half again at the center.

Materials and Structure

These folded shapes are used for a variety of tape-like materials, including woven tape, knitted tape, and synthetic leather. Depending on the base structure, thickness, and surface finish, the ease with which fold lines form, slipperiness during sewing, and edge durability will vary.

Some woven or knitted tapes have selvage edges that are less likely to fray when cut. On the other hand, folded processing is used for cut synthetic leather and thick materials to conceal the cut edge. Four-fold structures tend to create thickness and firmness in the cross section because of the overlapping layers.

• Single-fold is a shape that hides the cut edge on the folded side and makes the opposite side easy to use as the seam allowance side.
• Double-fold is used when both visible edges need to be neat.
• Four-fold can be finished so that both edges are enclosed, and it is also used for loops and handles.

How to Read Width and Main Applications

Tape width is often shown by the finished width after folding, rather than the open width before folding. However, the display standard varies by product and supplier, so when ordering, confirm the finished width, open width, thickness, and fold direction from the spec sheet or actual sample.

Single-fold and double-fold tape are used for trimming that tidies seam allowance and edge appearance, decorative stitching, and narrow facing applications. Four-fold tape is used for parts that need strength and thickness without exposing both edges, such as belt loops, tabs, handles, and the base for piping.

Selection and Handling Notes

For the intended application, check not only the finished width but also the material stiffness, the thickness of the folded section, the required strength, and whether the overlap can be sewn on a sewing machine. When following curves, hard tape or thick four-fold tape can easily cause lifting or wrinkles, so confirming sewability through a prototype is important.

When washing or product washing is required, check in advance for shrinkage, color transfer, surface peeling, or cracking of both the tape and the main textile. If the cut edge or stitching finish of woven tape is inadequate, it can lead to fraying, so decide the edge finish and securing method according to the application.

Differences from Similar Terms

Double-fold may refer to a shape in which the tape is folded once at the center, and the number of folded edges differs from single-fold or double-fold. However, the use of terms such as double-fold, single-fold, and four-fold varies by manufacturer and practice, so it is important not to judge the cross section from the name alone.

Triple-fold often refers to edge finishing or hem finishing in the sewing process, and it is treated separately from preformed triple-fold tape. Bias tape refers to tape cut on the bias grain of the textile, while single-fold, double-fold, and four-fold indicate the folding method, so the two are names from different viewpoints.

Frequently Asked Questions