Isacord 1000m ポリエステル 3710 ブルーバード 糸

The color of this 3710 Blue Bird is so vibrant and consistent through the whole spool. Even at high speeds, the thread runs smoothly without any fraying or breakage.

I've been using this thread for heavy satin stitch fills, and it outlasts other polyester threads I've tried by a noticeable margin. The tensile strength makes a real difference when running high-speed commercial machines.

The smoothness of this thread is unreal—it glides through the needle without a single snag, even on dense designs. I’ve tested it against rayon and the strength difference is obvious. This blue bird shade is my new go-to for logo work.