To complete the unit requirements safely and effectively, the individual must:
describe production problems that could be created by not reading or understanding the job specifications
list work health and safety (WHS) factors to consider when mounting and proofing flexographic plates
describe the most common cause of photopolymer plates crazing on the image side
explain the importance of printing plate resiliency
list main advantages of using thin photopolymer plates in process printing
outline faults that may be detected on new plates
identify types of solvents used on photopolymer plates
describe benefits of optical mounting
explain the purpose of binding plates after mounting
outline possible print faults that could be eliminated by using a cushion mount
list WHS factors to consider when installing printing cylinders or sleeves
describe precautions to ensure the plates and cylinders or sleeves are not damaged during installation
explain what to check to ensure plates and cylinders or sleeves have been installed correctly
list WHS precautions to be observed when webbing up the machine
explain how to determine position of the reel
demonstrate how the substrate is pulled into the machine
outline consequences of insufficient unwind tension
describe consequences of excessive unwind tens
outline the function of the ‘Dancer’ roller on a web machine
explain the function of the PIV unit
demonstrate knowledge of how to make adjustments to the PIV
describe the function of the lay-on roller
outline effects of excessive lay-on roller pressure
describe what can happen if the web is not spliced correctly
explain how the particular web viewing device works
list WHS precautions for setting up the delivery
explain how the web is controlled in the rewind unit
describe the result of incorrect rewind tension
outline remedial steps if there is a possibility of ink marking in the rewind
explain the function the air blast plays in the delivery of sheets
list WHS precautions for preparing inks and additives
identify details to check an ink’s suitability for the printing process
outline special end-use requirements that may be necessary
describe the main functions of a pigmented extender used in flexographic printing
explain the purpose of adding plasticisers to flexographic inks
list additives used in flexographic inks
outline the range, in seconds, for zahn cup measurements
describe the effect foaming has in a zahn cup when measuring ink viscosity
identify recommended pH range when printing with aqueous inks
list precautions to observe to minimise waste when preparing ink
describe how to determine shelf life of most inks
outline conditions relevant to storing inks and additives
list conventions for labelling mixed ink
list WHS factors to consider when setting up the machine
identify advantages of centring all machine controls
describe checks to be made on cylinders and gears
outline checks to do prior to cylinder or sleeve installation
identify the angle chamber blades should be set at
outline the main advantage of gauging up and dry register prior to printing a job
describe the cell count of the anilox roller used when printing solids
explain why water treatment additives should be used in a central impression drum and chill roller coolant system
list advantages of laser engraved ceramic anilox rollers
demonstrate knowledge of the anilox roller and what it measures
list possible reasons for anilox wear
describe the type of job printed using a hexagonal cell configuration
identify the recommended web temperature when printing polypropylene film
explain the method of drying used when printing on polythene by the flexographic process
list factors affecting drying rate of liquid inks
list factors affecting drying of aqueous inks
identify the operating range of UV lamps
list WHS precautions to be observed when slitting on the machine
explain how a cold seal is formed
outline reasons for a printed product to be punched
describe what to consider when setting hole punching in relation to repeat length
outline consequences of excessive pressure on the slitters
describe why is it necessary to graduate drying speeds of each progressive colour, so first-down colours dry faster the subsequent colours
explain why, in flexographic printing, that as press speed increases so does colour strength
list causes of a decrease in web tension
outline consequences of increasing rewind tension after the roll has been partially rewound
identify the major cause of a telescopic roll
describe print characteristics related to excessive printing pressure
list causes of picking when printing multicoloured work
identify print faults from using an over-reduced ink
outline problems that can cause lateral streaks in uneven printing
describe causes of moire patterns when printing by the flexographic process
outline consequences of air being trapped under mounted plates
name the instrument used to identify retained solvent trapped in the print
explain the purpose of taking Dyne readings
explain the purpose of the crinkle test when testing an ink
outline consequences if an excessive final drying temperature was used when printing polypropylene film
identify the ink property that can be adjusted to reduce dot gain
demonstrate understanding of correctly checking ink viscosity while using ink pumps
identify problems resulting from excessive use of slow solvents
explain why laminating inks, once printed, appear dull and become easy to scratch
outline the result of excessive print area tension
list some of the problems the printer may associate with cold seals
locate machine manuals, safety and other documentation relevant to this task, and outline information included in these documents.