After commercial laundry shirt pressing we sometimes encounter dark or discolored spots on the collar tips. During shirt manufacturing, your collars are constructed with two layers of fabric held together for shape and stability. This process is called interfacing. Interfacing requires an adhesive, or glue, to be applied between the layers to hold them in place prior to completed collar construction. If too much adhesive is used, the heat from the commercial laundry press will cause the excess bonding agent to soften and leave a permanent stain on the tips or surrounding area. There is no way to prevent or know of such instance prior to cleaning. The shirt manufacturer can be held responsible for this type of adverse discoloration.