Machine purging compounds

The recent efforts of Ultra System have been focused entirely on the development of "purging compounds" for specific application sectors. Machine cleaning is an important part of the production cycle for moulders and if the cleaning process is carried out correctly it eliminates traces of burnt resins, masterbatches, additives and pigments, even in dead zones.
Machine cleaning compounds can be divided into four generations. The first consists of methacrylate and polymer blends which, while inexpensive, are certainly rather inefficient as cleaning materials. The products belonging to the second generation are more efficient, consisting of materials containing high proportions of methacrylates and polymers and also glass fibres and inorganic salts, like marble powder. However, although these products are undoubtedly more effective, they cause rapid wear of metal surfaces.
The third-generation products are less abrasive and, in cleaning terms, guarantee a good result, but they need long dwelling times and can smell unpleasant. The active components of these products are inorganic salts that absorb the traces of resin, and their chemical reaction is obtained through surface-active agents that have medium- and long-chain molecules.
The fourth-generation purging compounds have the advantage of not being abrasive; in addition, they react rapidly. The Ultra Plast range can be classed among these last generation products. These compounds are easy to remove and particularly effective against "black spots" (a frequent problem with transparent resins). They have a high foaming power, and are thus able to reach even the most inaccessible parts of the machine. Ultra Plast's products are FDA-approved and comply fully with all food industry regulations.
One problem that often arises when using cleaning compounds is the "milky shadow" phenomenon (due to traces of purging compound). This shadow appears on the first pieces that are produced following a thorough "after-purging" with neutral materials. To get round this problem, Ultra System has developed a new type of compound, Ultra Plast High-C, which guarantees deep cleaning without leaving residue or traces. This makes it particularly suitable for polycarbonates and polycarbonate-like resins, which require excellent transparency. According to the manufacturer, it is currently the only purging compound on the market that, in the production of visors, lenses, headlights and ceiling lights, rapidly ensures clear and brilliant pieces after changing colours or materials.