A hickey, also known as a screen-ejection defect, is a printing imperfection that appears as a small dot or line on a printed substrate. The most common cause of hickeys is a foreign particle such as dust or lint that becomes lodged in the screen mesh of a screen printing press. When the screen is subsequently wiped with a squeegee during the printing process, the foreign particle is forced through the mesh, leaving a small hole. As the squeegee continues to move across the screen, ink from the stencil is forced through the hole and onto the substrate, resulting in a hickey.
Hickeys can also be caused by static electricity, which can cause the ink to become electrically charged and adhere to the substrate in a random pattern. In some cases, hickeys may also be caused by improper screen tension, which can cause the screen to sag and create small voids in the stencil through which ink can bleed.
While hickeys are generally considered to be a cosmetic defect, they can occasionally have a functional impact as well. For example, if a hickey falls within the printed image area of a barcode, it can render the barcode unreadable.
A hickey, also known as a screen-ejecting pin or screen-lock pin, is a device used in screen printing to remove the mesh from the screen after the image has been printed. The hickey is inserted into a hole in the screen and then pulled out, which causes the screen to eject the mesh.
Hickeys are typically made of metal or plastic, and come in a variety of sizes and shapes. They can be round, oval, or square, and have either a smooth or textured surface. Some hickeys also have a notch or groove on one side, which helps to grip the mesh and prevent it from slipping.
Hickeys are an essential tool for screen printers, as they allow for quick and easy screen changes. They are also relatively inexpensive, which makes them a good choice for businesses that do a lot of screen printing.