To complete the unit requirements safely and effectively, the individual must:
outline production problems that can eventuate if job specifications are not read and/or understood
identify the person to discuss production problems with
list work health and safety (WHS) factors to consider when mounting and proofing flexographic plates
discuss the most common cause of photopolymer plates crazing on the image side
explain the importance of printing plate resiliency
describe the main advantage of using thin photopolymer plates in process printing
list faults that may be found on new plates
describe the type of solvents to use on photopolymer plates
explain what V-block mounting is
describe how V-block mounting is achieved
list benefits of optical mounting
outline the purpose of binding plates after mounting
explain possible print faults that can be eliminated by using cushion mount
explain any WHS factors to be considered when installing printing cylinders or sleeves
describe precautions to ensure plates and cylinders or sleeves are not damaged during installation
outline checks to ensure plates and cylinders or sleeves have been installed correctly
discuss WHS precautions for webbing up the machine
explain how to determine position of the reel
describe how the substrate is pulled into the machine
explain the result of insufficient unwind tension
discuss the result of excessive unwind tension
describe the function of the ‘dancer’ roller on a web machine
explain the function of the positive input ventilation (PIV) unit
discuss the result of adjustments to the positive input ventilation (PIV) unit
describe the function of the lay-on roller
discuss the effect of excessive lay-on roller pressure
describe the effect of the web not being spliced correctly
explain how the particular web viewing device functions
outline WHS precautions for setting up the delivery
explain how the web is controlled in the rewind unit
outline the result of incorrect rewind tension
discuss remedial steps to take if there is a possibility of the ink marking in the rewind
explain the use of air blast play in the delivery of sheets
discuss WHS precautions for preparing inks and additives
outline how to determine an ink’s suitability for the printing process
explain special end-use requirements that may be necessary
outline the main function of a pigmented extender used in flexographic printing
describe the effect of adding plasticisers to flexographic inks
explain why other additives are used in flexographic inks
explain the range, in seconds, for zahn cup measurements
describe the effect foaming has in a zahn cup when measuring ink viscosity
explain the recommended ph range when printing with aqueous inks
outline precautions to minimise waste when preparing ink
explain the shelf life of most inks
identify conditions relevant to storage of inks and additives
describe conventions for labelling mixed inks
list WHS factors to consider when setting up the machine
explain the advantage of centring all machine controls
list checks to make on cylinders and gears
outline checks to perform prior to cylinder or sleeve installation
explain the angle chamber blades should be set at
discuss the main advantage of gauging up and dry register prior to printing a job
discuss cell count of the anilox roller for printing solids
outline 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
describe three things relating to the anilox roller that a roller scope measures
explain possible reasons for anilox wear
outline the type of job that is printed using a hexagonal cell configuration
describe 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 the drying rate of liquid inks
identify factors that affect drying of aqueous inks
explain the operating range of UV lamps
explain why it is necessary to graduate drying speeds of each progressive colour, so that first-down colours dry faster than subsequent colours
explain why in flexographic printing, the colour strength increases as the press speed increases
identify possible causes of a decrease in web tension
describe the result of increasing rewind tension after the roll has been partially rewound
explain the major cause of a telescopic roll
list print characteristics related to excessive printing pressure
outline causes of picking when printing multicoloured work
explain print faults from using an over-reduced ink
discuss problems that can cause lateral streaks showing up in uneven printing
describe causes of moire patterns when printing by the flexographic process
explain what happens when air is trapped under mounted plates
describe which instrument is 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 the result if an excessive final drying temperature was used when printing polypropylene film
explain what ink property can be adjusted to reduce dot gain
discuss the effect of using the ink returning from the ink fountain when checking viscosity for ink while using ink pumps
list problems that result from excessive use of slow solvents
explain the effect of the ‘yield value’ of ink on the ink transfer of halftone dots
discuss why laminating inks, once printed, appear dull and easy to scratch
explain the result of excessive print area tension
identify some of the problems associated with cold seals
identify the location of machine manuals, safety and other documentation that are relevant to this task, where they are kept, and describe the information included in them.