This process is where customers digital data is specifically prepared and transferred onto the appropriate format for futher stamper production. In case the parameters of the material provided by a customer do not comply with stamper and disc replication requirements, technical data can be corrected during the premastering stage
We make sure that the material provided by customers meet all the required standards and is readable by a player. The material is recorded into the information storage device and tested in a special testing device for suitability for futher stamper production.
At this stage, a unique mould, so-called stamper, is produced. The stampers are used to make a disc ingot for further replication. To produce a stamper the glass mould with a piece of photo-resist (light-sensitive layer) is used, in which a laser beam “records” the information that is going to be in replicated discs. Recorded glass mould is placed in a special galvanic facility where the nickel layer is grown with a help of electrolysis. Afterwards, a layer of nickel is separated from the glass mould. This produces a stamper a negative disc image, which is used to replicate the discs.
When the stamper is made, the disc replication is started. Thoroughly cleaned stamper is placed into a mould, which is closed and the casting process begins. Using a syringe injects with a controlled, up to ~ 360 degrees heated liquid polycarbonate, a CD/DVD master is poured out. It already contains digital information, but it still cannot be scanned by a laser beam, because the disc is completely transparent.
When replicating CDs, the one disc mould is prepared (thickness – 1,2 mm), while replicating DVDs – two disc moulds are prepared and glued afterwards (thickness – 0.6 mm of each).
One of the clear disc side with the imprinted information is covered with aluminium. This acts as a mirror reflecting a laser beam to read the information.
When replicating DVDs, the number and composition of metallisation layers depend on DVD format and capacity (DVD-5, DVD-9 or DVD-10).
Metal layer formed on the disk after metallisation process is very thin and in case of any infringements the information will not be readable. That is why the discs are covered with a special varnish dried with UV rays. When replicating DVDs, the moulds are glued together using special UV glues without varnishing, because the information stays in the inner side and does not have to be protected.
Screen printing or offset printing method can be used to cover the discs according to the customers provided graphic design. The latest technologies allow us to print the discs according to the highest quality standards.