Double-dot

Definition and Overview

Double-dot is a type of dot coating in which adhesive resin is applied in dots to a fusible interlining. It is intended to achieve both retention on the base fabric of the interlining and adhesion to the outer fabric by creating a two-layer structure of resin dots.

It does not refer to the type of fusible interlining itself, but to the processing method for the adhesive resin applied to one side of the interlining. It is handled separately from the type of base fabric, such as nonwoven interlining, woven interlining, or knit interlining.

Applicable Areas and Role

Double-dot processed fusible interlining is used in areas where shape is to be maintained or stretch is to be suppressed, such as collars, button plackets, cuffs, facings, and waist areas. It is considered for thin to medium-weight outer fabrics when it is desirable to preserve the fabric's surface texture and suppleness as much as possible.

By bonding the interlining, it improves ease of handling during sewing and helps prevent loss of shape during wear. However, the finished stiffness and adhesion durability depend not only on whether it is double-dot, but also on the combination of base fabric, resin, and bonding conditions.

Materials and Types

The base fabric of fusible interlining may be nonwoven, woven, or knitted, using materials such as polyester. In double-dot, the properties and amount of the lower and upper layer resins are adjusted to balance fixation to the interlining and adhesion to the outer fabric.

Compared with ordinary single-layer dot coating, it is characterized by making it easier to control the amount of resin that contacts the outer fabric and the flow during bonding. However, the terminology and the specific two-layer structure may vary depending on the interlining specifications and supplier.

How to Choose and Precautions

When selecting, check the thickness, density, elasticity, fuzz, and surface unevenness of the outer fabric, as well as the desired stiffness. For thin and delicate outer fabrics, it is important to choose an interlining that is less likely to leave resin marks on the surface side and less likely to impair the texture of the outer fabric.

While a stiffer interlining or a specification with more resin makes shaping easier, it may cause a hardened feel, fading, or bleed-through depending on the outer fabric. For stretch materials, consider knit interlining or similar options that can accommodate the stretch of the outer fabric, and confirm that it does not interfere with the required elongation.

• Layer the outer fabric and interlining, and compare the texture and appearance before and after bonding.
• Light colors, thin fabrics, glossy materials, and fuzzy materials should be checked particularly carefully because surface changes are easier to see.
• Products that undergo garment washing, laundering, or dry cleaning should also be evaluated after the actual process.

Precautions for Bonding and Sewing

Bonding should follow the temperature, time, pressure, and cooling conditions specified for each interlining. If the conditions are insufficient, adequate peel strength may not be obtained, and excessive heat or pressure may cause glossing, shrinkage, bleed-through, or changes in texture of the outer fabric.

Before mass production, perform trial bonding using the outer fabric and interlining to check for peeling, bubbling, and surface fading. After bonding, allowing sufficient cooling before cutting and sewing makes it easier to confirm the stability of the bonded area.

Frequently Asked Questions

Are double-dot and fusible interlining the same thing?

No, they are not the same. Fusible interlining is the general name for interlining that is attached to the outer fabric with heat and pressure. Double-dot refers to the method of processing that fusible interlining with adhesive resin in a two-layer dot structure. It is a separate classification from whether the base fabric is nonwoven, woven, or knitted.

Can double-dot be bonded to any outer fabric?

Compatibility with the outer fabric must be checked. With thin fabrics, light colors, glossy materials, fuzzy materials, and stretch materials, bleed-through, fading, a hardened feel, or inhibition of stretch may occur. Perform trial bonding with the outer fabric and interlining to be used, and also check after the assumed processing such as laundering.

What should be done if the interlining peels off after bonding?

First, check whether the bonding conditions, such as temperature, time, pressure, and cooling, match the interlining specifications. If there is no problem with the conditions, review the compatibility between the outer fabric's processing or surface properties and the resin, as well as the interlining selection. Evaluate not only peel strength, but also changes in appearance.