Early CTP Plates

The first CTP plates, also known as ‘conventional CTP plates’, were imaged by visual lasers.

These plates have several critical limitations:

• They are light-sensitive. This forced manufacturers to develop sealed platesetters and operators had to handle the plates under dark room conditions.
• Light intensity in the exposure process must be strictly controlled to prevent under- or overexposed plates.
• After imaging, the plate must be chemically developed before it can be used. The toxic waste from this process has to be carefully disposed of.

The difficulties of handling conventional CTP plates inspired the prepress industry to invent thermal sensitive plates.