Stay Tape
Stay tape is a reinforcing tape used on seam allowances and similar areas to prevent seam slippage, where warp and weft threads shift and create gaps when force is applied to a woven fabric seam.
Definition and Overview
Stay tape is used on loosely woven fabrics, low-density fabrics, and fabrics made with slippery filament yarns to prevent yarn slippage near seams. Seam slippage is different from the fabric itself tearing; it is a condition in which the warp and weft pulled by the sewing thread move and the seam opens up and becomes visible.
Areas of Use and Role
It is used on seams that are subjected to concentrated pulling during wear, such as pocket openings, side seams, inseams, center back seams, neck openings, and armholes. It reinforces the seam allowance side, helps control fabric movement during sewing, and makes it easier to maintain the seam's appearance and durability.
On lightweight or slippery fabrics, yarn slippage may occur even if only the outer fabric is sewn firmly. By distributing the load with tape, it helps reduce seam allowance tearing and seam opening. However, it is not a material that restores the fabric's inherent strength.
Types and Cutting Direction
Tapes include ones cut straight along the grain, ones cut on the bias, and half-bias types with intermediate stretch between the two. Because stretch and conformity differ depending on the cutting direction, choose according to the shape of the area to be reinforced and the required stretch.
The straight type is suitable for straight areas where stretch should be minimized. The bias type follows curves more easily and is used for areas such as necklines and armholes that require moderate conformability. There are adhesive types with glue and non-adhesive types that are sewn in and secured, and they are used according to the outer fabric and the process.
- Adhesive type: easy to temporarily fix and secure with an iron or press, helping stabilize the process.
- Non-adhesive type: consider it for heat-sensitive materials or when you want to avoid changes in texture caused by adhesion.
- Straight type: suitable for areas where preventing stretch is the priority.
- Bias type: suitable for areas where conformity to curves and moderate stretch are needed.
Selection and Precautions for Adhesion and Sewing
Select the width by considering the seam allowance width, the distance from the seam line to the tape edge, and the area to be reinforced. If the tape is too narrow, the reinforced area will be insufficient; if it is too wide, the seam allowance may become stiff or fading may appear on the surface. It is important to avoid materials that are extremely harder than the outer fabric.
For adhesive types, confirm the temperature, pressure, and time using scraps of the outer fabric before use. Excessive heat or pressure may cause changes in texture, glossiness, or adhesive bleed-through. During sewing, do not stretch the tape; sew the tape and fabric at the same feed amount to prevent seam puckering and waviness.
Differences from Similar Terms
Stay tape is a reinforcing material used to suppress yarn slippage in woven seams. Anti-stretch tape is a broader term for uses such as controlling stretch and preventing loss of shape at shoulder seams and pocket openings, and it may not be intended mainly for preventing seam slippage. Clarify the required performance in the specifications.
Non-slip elastic band is an accessory material used to prevent garments or straps from shifting on skin or over other clothing. By contrast, stay tape is aimed at the movement of threads within the fabric structure. The names are similar, but their uses, installation positions, and required performance differ.
Frequently Asked Questions
What kinds of fabrics require stay tape?
It is considered for woven fabrics where the warp and weft are likely to move when force is applied to the seam. It can be especially effective for lightweight fabrics, open weaves, and slippery fabrics. However, whether it is needed depends on fabric density, seam direction, ease, and wearing conditions, so confirmation through prototypes is necessary.
Are stay tape and anti-stretch tape the same?
They are sometimes treated as the same, but the performance emphasized is different. Stay tape mainly suppresses yarn slippage around seams. Anti-stretch tape mainly prevents fabric stretch and loss of shape, and is selected according to the area and fabric issue.
What should be checked when using the adhesive type?
Before mass production, perform an adhesion test on scraps of the outer fabric and check the adhesive strength, texture, glossiness, bleed-through, and condition after washing. In addition to the pressing conditions, also check whether the taped area shows through on the face side as impact marks or fading.
