FLEXO INSIGHT: Platemaking technologies

All of the current flat sheet platemaking technologies are negative working, and the quality of the finished plate is dependent on the quality of the negative film.

Liquid analogue photopolymer technology is predominately used for the production of plates for the corrugated industry. Water-based and so environmentally friendly and safe, the big benefit of liquid systems is that they are cost effective. Experience has revealed that 30% reclaimed resin can often be achieved from the non-image area of corrugated plate.s, so cost savings can be substantial. The speed at which they can be made is also advantageous.

In recent years, renewed interest in solid analogue and digital sheet photopolymer has taken place. These systems are based on conventional plate processing technology, with the vital exception that the solvent used is water. Print quality improvements are also claimed for some of the latest plates.

Solvent-based analogue platemaking has continually been refined to improve the printing performance and consistency. Plate and platemaking systems are universal, and each manufacturer has designed its plate chemistry to give specific characteristics: wide exposure latitude; high resilience; high ink transfer; and high print contrast.

By using advanced platemaking techniques that refine and accurately control the platemaking exposure, a very consistent print quality can be achieved with conventional analogue plates.

In solvent-based digital platemaking the plates have smaller dots and as a result better printing capability. When you compare analogue to digital print it can be clearly seen that the higher quality image is produced from the digital plate.

The growth of digitisation and cost pressures will end the use of negative film. The increased awareness of environmental issues will be a key driver for aqueous-based platemaking systems. Solvent-based analogue platemaking systems will eventually be replaced by digital, due to commercial pressure and the demand for consistent quality; but the key driver is improved workflow efficiency.