Hotmelt is a solvent-free, thermoplastic adhesive that remains solid at room temperature and liquifies upon the application of heat. In the garment decoration industry, it is typically composed of Polyurethane (PU) or Copolyamide and serves as the structural bridge that fuses decorative media—such as DTF prints or Flex Foils—to textile fibers.
Why It Matters: Impact and Use
Hotmelt technology is the “invisible engine” behind the durability of modern apparel. Choosing the correct hotmelt application is a critical technical factor in E-E-A-T (Expertise, Authoritativeness, and Trustworthiness), as it directly determines the wash-fastness and “hand-feel” of the finished product.
Industrial Resistance: High-quality hotmelts are designed to withstand high-temperature laundry cycles and chemical dry cleaning without delaminating (peeling).
Versatile Application Forms: * Solid/Layered: Found on the back of Flex Foils (HTV). It is a pre-applied, uniform layer that ensures edge-to-edge adhesion once cut and pressed.
Powder Form: Used in Direct to Film (DTF) printing. The powder is shaken onto wet ink, where it “gels” during curing to create a custom adhesive backing for complex, multi-colored designs.
The Bonding Process: During heat pressing, the hotmelt reaches its “melt flow” point, penetrating the porous structure of the fabric. As it cools, it solidifies into a flexible, permanent bond that moves with the garment.
Flexibility & Recovery: Unlike old-fashioned glues, modern hotmelts are engineered to be “stretchy.” This prevents the design from cracking when the fabric is pulled, making it ideal for performance wear and spandex blends.
Comparison: Hotmelt Applications
| Form | Media Example | Application Method | Best For |
| Integrated Layer | MagiCut Flex Foil | Pre-applied to the vinyl. | Single-color lettering, names, and numbers. |
| TPU Powder | DTF Powder | Shaken onto wet pigment ink. | Full-color, high-detail photographic transfers. |
| Web/Film | Double-sided Adhesive | Placed between two fabrics. | Appliqué, patches, and hem bonding. |
