Toothbrush Manufacturing

ICA02_Introduction Toothbrushes have come a long way over the centuries. Since 3500 BC, people around the world have been using tools to clean their teeth. Egyptians and Babylonians made brushes by fraying the end of twigs. In the 15th century, the Chinese invented the first toothbrush by attaching bristles from pigs’ necks onto a bamboo handle. The design was adapted by Europeans, who modified the design using soft horsehairs. Process selection In this case injection molding process is considered for manufacturing the brush handle and followed by other processes to complete entire the tooth brush First, The Materials Are Gathered The handles are made out of plastic and the bristles are made out of natural boar or synthetic fibres such as nylon.. The Handles by Moulding Plastic pellets are placed in a moulding machine, which melts the plastic. Rotating screws turn the liquid plastic into the moulds. Small “cores” are inserted into the handles which makes the holes, into which the bristles are later placed. The handle moulds are tightly clamped onto a pressuriser. This helps them to cool. Once they have cooled, the handles are pushed out of the moulds. The manufacturing of multi colour plastic tooth brushes slightly varies in the process as it has to be in multi colour, multiple materials has to be used to make the handle. Multicolor Molding There are different methods for multicolor injection moulding Double injection, two types of raw materials while injection into the mold cavity. The technology is usually based on pre-injection rate and geometry of the cavity to determine the material distribution and two kinds of raw materials in the mold point. When using this method requires injection presses with very high accuracy and excellent repeatability of each cycle. Some flexibility over the technology used for the injection occasions, such

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as processing for raw materials hampered by poor liquidity, or the component parts function as