Janome has just introduced a new variety of sewing needle called the Purple Tip Needle.
Purple Tip Needles are designed to prevent skipped stitches with heavy fabrics, including knits, while doing sewing and embroidering. They feature a ball point tip to prevent fabric thread breakage and a special cobra shaped head to form a proper needle thread loop so that it prevents skipped stitches caused by the fluctuation of the fabric. And they're available in a heavier 14 size.
Purple Tip Needles are recommended for:
Embroidery with a high density design and/or thick fabric
Fluffier thread like cotton
Quilting multiple layers which normally resist needle penetration
Sewing knit, tricot, and synthetic fabrics like thick polyester