BLISERING BLOCKING DOT SHARPNES
INADEQUATE DRYING GLOSS HICKIES
INCONSISTENT COLOR REPRODUCTION INK/ WATER BALANCE INK MILEAGE
MARKING MISREGISTER MISTING/SLINGING
MOTTLED SOLIDS PICKING/LINTING

PILING

PLATE BINDING POOR RUB AND SCUFF RESISTANCE SCUMMING
ROLLER STRIPPING TINING/TONING TRAPPING
WEB BREAKS  
     

Problem

Cause

Solution

BLISERING
A moisture explosion in the paper- looks like a bubble on both sides of web and generally in heavy coverage areas.

Over heat is too high. Reduce oven temperature. Consult ink manufacturer to provide ink that can be cured at a lower temperature.
Excess dwell time is oven. Correlate press speed. Web dwell time in dryer, and chill roll temperature to optimum performance levels.
Defect in paper causing excessive moisture content, improper density or base. Blistering may not occur the full machined reel. Run roll from different paper machine position. Run a substitute stock. Consult paper manufacture and reject if necessary.
Pigment strength of ink is too low, requiring more ink than normal to be carried in heavy coverage area. Consult ink manufacturer to adjust.

Problem

Cause

Solution

BLOCKING
Undesired adhesion between printed signatures or sheets in a bundle or load causing them to stick together.
Refer to INADEQUATE DRYING section of this guide.  

Problem

Cause

Solution

DOT SHARPNESS
Printed halftone areas appear muddied and shop higher values than the "Prog" proof show.
Too much form roller-to-plate, plate-to-blanket, or blanket -to-blanket pressure. Check setting and correct to proper pressure.
Doubled or slurred dots. Adjust plate - to - blanket pressure. Make sure blanket is secure. Check press for roller slippage are mechanical stability to high speeds.
Ink body is too long and is squashing at the point of impression. Consult ink manufacturer to provide stiffer ink.
Ink is too water receptive. Consult ink manufacturer.
Piling. Refer to PILING section of this guide.
Plate was not sharp enough to compensate for normal dot spread from film to plate to press. Have cameraman and plate maker cooperate in making sharper halftones, negatives, positives and plates.
Improper ink/water balance. Adjust ink an water settings. Consult ink manufacturer.

Problem

Cause

Solution


INADEQUATE DRYING
Printed halftone areas appear muddied and shop higher
values than the "Prog" proof show.

 

Dryer temperature too low to speed of web. Insufficient solvent being released from ink film. Increase dryer temperature to specification level.
Ink film thickness excessive.

Run less ink or consult ink manufacturer to increase strengths for this purpose.

Inadequate evacuation of solvent vapors clinging to web as it leaves dryer. Consult ink manufacturer.
Different Pantane Color Formula Guides. Increase velocity of air in air knife scavenger at dryer exit.
Chill system not working properly; ink resins are not setting hard enough. Lower chill roll temperature. Caution : Watch for chill roll condensation.
Stock is not porous enough or has too high water content. Switch stock to correct porosity or water content.
PH/ conductivity of fountain solution is incorrect. Adjust ph/ conductivity to proper level. Refer to ink manufacturer.
Ink takes on too much water. Consult ink manufacturer for proper adjustment.
Plate dampening is uneven. Keep dampeners clean and free from accumulated dirt. Prevent draft, check windows, vents, and forced air systems.
Ink film is only surface dried is oven and still wet underneath. After chilling ink solvent will work its way toward surface causing set - off. Most likely to offer with heavier than normal ink film thickness, very nin absorbent stocks. On high oven temperature. Reduce speed of press. Adjust oven temperature.
Ink films do not try at normal dryer temperature. Consult ink manufacturer for inks that dry at low temperatures.

Problem

Cause

Solution

GLOSS

There is a decrease in the normal reflection of light from the dried ink surface whether observed visually, or red via glassmeter.
Paper too ink absorbent. Paper surface very rough and grainy. Paper has poor gloss. Consult paper manufacturer to obtain stock with more ink hold out. Obtain stock having a smooth surface. Obtain paper with better gloss.
Dryer temperature is too high. Consult ink manufacturer to obtain low temperature inks. Decrease press speed to allow decrease of oven temperature.
Press dampeners - too much water being introduced in to linking system. Cut back on amount of fountain solution used. Consult ink manufacturer to decrease water receptivity of ink.
Ink film thickness too low. Increase ink film thickness being carried on web.
Excessive ink vehicle penetration in to web. Reduction of heat in dryer. Increase press speed to reduce oven dwell time, maintain sufficient chilling capacity. Consult ink manufacturer, obtain inks with better hold - out.

Problem

Cause

Solution

HICKIES
Doughnut shaped or irregularly shaped white spots surrounding a small spot of ink.
Dried ink particles. Avoid dried ink skin when removing ink from cans or kit. Protect ink remaining in a can or kit from oxidation, drying and formation of ink skin by applying a sheer of paper or plastic on top of it. Clean the press throughly and remove all dried ink in the fountain or on the rollers before inking up the press. Prevent the ink in the ink fountain from mixing with dried ink around tie ink fountain edges. Prevent ink from caking on the ends of rollers by lubrication and manual washing. Use a leather covered or a grained rubber roller. This will pick up hickies that are passed on to the plate. Remove the leather- covered rollers and clean them thoroughly as needed.
Flakes of ink rollers. Recondition the rollers and drums. Replace if necessary.
Glazed rollers. Use one of the specially formulated glaze - removing materials or remove the form rollers, and alternately scurb the form rollers and the drums with pumice powder and ink solvent to remove the glaze.
Disintegration of dampener roller sleeves or rollers due to wear. Replace suspect roller sleeves or roller with new one.
Foreign particles ( dirt ) from ceiling have fallen in to press. Vacuum clean the ceiling and everything overhead where dirt can accumulate. Paint the ceiling if necessary, or hang plastic sheeting over the press to catch the falling particles. Use a leather covered or a grained rubber roller. This will pick up hickies that are passed on to the plate. Remove the leather covered rollers and clean them thoroughly as needed.
Loose paper dust on web. Install vacuum sheet cleaner. Consult paper manufacturer.

Problem

Cause

Solution

INCONSISTENT COLOR REPRODUCTION
Color hues when printed do not match proofs.
Paper proofed on is not the same as that being printed. Paper being printed is more absorbent. Adjust ink film thickness to that of the proof. Consult ink manufacturer to adjust hue and ink hold - out to match the proof on the actual paper being printed on. Consulate paper manufacturer to see if paper is available which more easily duplicates the paper proofed on.
Excessive heat in dryer results too much penetration of the ink resin, resulting in loss of gloss - ink is overdried. Reduce fryer temperature increase press speed.
Special, spot color does no match proof. Consult ink manufacturer's.

Problem

Cause

Solution

INK / WATER BALANCE
Frequent adjustments required on press to maintain print quality.
Excessive or insufficient dampening solution being run. Reduce or decrease dampener settings.
Fountain solution too weak or improperly mixed. Check pH/ Conductivity and adjust accordingly. Refer to ink manufacturer.
Improper dampening roller settings. Re - set rollers. Be sure dampener form rollers are driven the vibrator roller or not the plate.
Improper ink from roller settings. Conduct ink stripe test to check form roller pressure.
Improper ink fountain settings. Adjust the amount of ink at fountain. Allow adequate time for adjustment to take full effect.
Weak ink, i.e. low color strength. Consult ink manufacturer for proper adjustment.
Ink taking up too much water. Consult ink manufacturer.

Problem

Cause

Solution

INK MILEAGE
More ink used per impression than normal
Lack of control on color densities. Adjust color densities to minimum, consistent with satisfactory print quality.
Ink penetration in to stock too rapid. Consult ink manufacturer for ink with more hold - out change to less porous stock.
Improper ink and water balance. Reduce amount of water carried.
Low pigmented inks. Consult ink manufacturer for proper tinctorial strength.
Excessive waste at start - up of run. Improve start - up procedures.
Improper estimate of coverage from job to job. Establish ink usage history so that these figures can be used to more accurately predict ink usage.

Problem

Cause

Solution

MARKING

Streaks, tracks, or smudges on web due to mechanical contact.
Grater roller. Install grater roller with sharper points. Increase pigment strength of ink so as to decrease in ink film thickness Carrie on web.
Web bustle wheels. Move wheels so as to contact non image areas only. If moving wheels is not possible, apply teflon tape to lessen abrasiveness of wheel surface.
Improper it flow through oven causing web to flutter and make contact with oven apparatus. Consult oven manufacturer for proper adjustment or adjust web tension.
Chill role not cool enough. Reduce chill role temperature so that post chill role web temperature is 90 degree F or less. Recommended chill role water temperature is 72 -75 degree F. Caution : If chill roll are too cold, condensation can occur. Reduce oven temperature to mainimum necessary to get the web through chilling and press folding delivery operation.
Web temperature reached in the oven is not high enough to drive off sufficient ink solvents. If flame impingement drier used adjust flame tips to impinge properly. If high velocity forced air drier used, raise circulating air temperaturer in oven until making is eliminated. Caution : Remember paper will burn at 451 degree F and can scorch at lessen temperatures. Decrease press speed. Increase air velocity through oven as to remove air and vapor layer clinging to moving web. Consult ink manufacture to obtain faster drying ink.
Dryer does not have capacity to properly handle press speeds reached or type of work printed. Consult dryer manufacturer.
Paper is very absorbent, very little ink penetration occurs to provide basic for binding to paper. Consult paper manufacturer change paper.
Ink film thickness is too great. Raise air temperature circulating in dryer. Increase air velocity circulating to help remove solvent vapor layer. Consult ink manufacturer, change to faster drying inks.

Problem

Cause

Solution

MISREGISTER
In the press running direction and side to side, after the press has been ser for proper registration, trouble arises when some condition prevents consistently good register.
MISREGISTER IN THE PRESS RUNNING DIRECTION  
One or more pleats are cocked or are not properly set on there cylinder. Plates should be handled more carefully on bending jig.
One or more pleats are printing longer or shorter than the others. Transfer the packing from blanket to plate to shorten the print, or from plate to blanket to lengthen the print, of from plate to blanket to lengthen the print. Maintain good tension on the web.
Uneven blanket packing. If one of the printing units is no pulling the web fast enough, web tension between it and the following unit will built - up until the web snaps back, causing misregister. Adjust blanket packing until the draws between the suits are equal.
Web tension is too low; the higher the tension, the better the register Increase web tension in the infeed section of the press.
Web tension changes during run because infeed tension changes. Equip presses with a constant - tension infeed.
Ink at the point of impression is too high causing the web to follow the blanket more than normal. This momentarily increases the tension in localized areas as a result can effect running register. Increase web tension. Reduce press speed. Consult ink manufacturer for tack reduction of ink causing problem.
Paper pile on blanket changes blanket diameter. Wash blanket more frequently. Change to paper that is more moisture resistant.
Paper roll out of round or having flat areas therein. Constant - tension infeed will help. Increase distance traveled by the web between infeed and the first printing unit. Change to a roll that does not have problem.
MISREGISTER SIDE - TO - SIDE ( More likely with wide webs 35+ inches):  
Non - uniform moisture across the web causes corrugation of roll, resulting inside - to - side misregister. Increase distance traveled by the web between the infeed and the first printing unit. The longer this distance and the higher the web tension, the more uniform the web will be. Use a pre heater on the infeed and the first printing unit to dry the paper, even out the moisture content and flatten the web. Equip press with a curved roller to spread and flatten the web.
Welts caused by unwrapping rolls in a high humidity area and allowing them to stand for a long time. These welts will occur no more than 25 mils in to roll. The small amount of corrugation will cause some side - to - side misregister just after splicing. Remove outer 25 miles of paper. Do not unwrap rolls until just before going to press.
Paper varies in calipaer across the web. Consult paper manufacturer.
Web has slack edges due to moisture pick - up while in the roll. Keep rolls from protected from atmospheric changes until they are mounted on the infeed and the web between the infeed stand. Increase distance traveled by the web between the infeed and the first printing unit in increase web tension, stretching the web tends to tighten slack edges. Equip the press with a curved roller on the infeed to spread and flatten the web. Adjust the eccentric - mounted infeed roller to balance edge tension.
Ink track too high at point of impression. Refer tip RUNNING DIRECTION MISREGISTER section of this guide. #6 under cause. Refer to RUNNING DIRECTION MISREGISTER section of this guide # 6 under solution.

Problem

Cause

Solution

MISTING / SLINGING

MISTING - Excessive amount of ink being thrown ink train rollers described as fine droplets.
SLINGING - Ink being thrown from rollers in filaments.

Too much ink on rollers.

Make press adjustment to decrease amount of ink carried or consult ink manfacture to increase ink strength and carry less ink or rollers.
Improper ink and water balance. Adjust ink and water balance to proper setting.
Ink is too long in body. Consult ink manufacturer.

Rollers are incorrectly set or in poor condition.

Rest roller based on manufacturer specification. Replace rollers if in poor condition.

Roller train too hot. Reduce temperature or increase flow of cooling water throw ink train rollers.

Problem

Cause

Solution

MOTTLED SOLIDS
Printed solid area is not uniform(smooth)ink appearance or density.

Stock has non - uniform surface formation.

Get better grade of paper. Consult ink manufacturer to provide weaker ink and minimize and penetrating tendencies.
Too much Printing pressure. Reduce printing pressure.
Improperly set ink from roller or roller ink poor conditions. Check condition and reset ink from roller to specification.
Improper ink and water balance. Adjust to paper ink and water balance.
Blanket has not been changed for a long time and has become worn and rough certain areas. Replace with a new blanket.
Poor ink transfer. Consult ink manufacturer.

Problem

Cause

Solution

PICKING/LINTING
PICKING - Lifting of the coating from coated stocks onto blankets, plates or rollers.
LINTING - Pulling fibers from uncoated stock.
Too much water reaching papers. Reduce dampener setting for proper performance.
Dampening solution concentration too high. Adjust dampening solution mix. Consult dampening solution manufacture.
Paper surface trash, coating dust, slitter or trimmer dust. Make tape pulls from blanket, consult paper manufacturer.
Base stock picks. If serious, reject paper, change to more lint or pick - resistant stock.
Pressure set too high for ink/ stock combination being used. Reduce impression pressure, repack to manufacturer specification.
Blankets is too high. Consult blanket manufacturer. Treat blanket or change it to a less tacky blanket. Check blanket wash.
Ink is too tacky for stock being run. PAPER: Refer to PICKING/ LINTING section of this guide. Consult ink manufacturer to lower tack of ink refer to PICKING/ LINTING section of this guide.

Problem

Cause

Solution

PILING
Build - up of paper coating lint, or ink on rollers, blankets or plates.
INK :  
Incase water logged. Reduce dampener setting. Consult ink manufacturer.
Incase poorly ground, contains a coarse, heavy pigment. Consult ink manufacturer. Have ink reworked or reformulated.

Problem

Cause

Solution

PLATE BINDING
(LOSS OF IMAGE) Part or all of image on plate does not take ink.
Improper packing of cylinders or roller not set correctly. Check specification and adjust if required.
Excessive amount of lint being deposited on place. Refer to PICKING/ LINTING section on this guide.
Excessive plate - to - blanket pressure causing plate wear. Re-set to specification. Use packing gauge to check pressure.
Improperly set ink and dampening form rollers. Roller could be too hard, check durometer. Also check setting; re- set if too much pressure exists.
Abrasive particles destroying image. Check ink grind, fountain solution, solvents, etc. Replace all contaminated material.
CHEMICAL:  
Too much acid in the fountain solution. Check pH/ conductivity and reduce acid to proper amount. Refer to Flint Corporation. Technical monograph TM84-5 on conductivity.
Too much gum in fountain solution. Re - etch plate and rub up image areas with press ink. Drain fountain solution and refill with tap water. If image returns, replace tap water with fountain solution containing less gum.
Plate cleaners and / or scratch removers have dried on plate image. Always rinse plate thoroughly and immediately after using such item.
Detergent remains or has somehow entered the fountain system. Make sure that all parts that comes in contact with cleaning detergent have been thoroughly rinsed before reinstalling in press.
Ink will not adhere to image area due to excess amount of fountain solution being accepted by the ink. Reduce dampener setting to minimum, if problem persist consult ink manufacturer.
Plate not completely developed. Plate was improperly developed with gum remaining on image area wash plate. If problem persist have plate remade.

Problem

Cause

Solution

POOR RUB AND SCUFF RESISTANCE
Printed ink film appears dry but exhibits poor rub and so scratch resistance when abraded.
Too much water runs on job or paper contains too much water. Reduce dampener setting. Change paper.
PH/ conductivity too high in fountain solution. Very high pH/ conductivity is indicated of too much acid in fountain solution which can retard or prevent drying of ink. Adjust pH/ conductivity according. Refer to flint ink corporation technical monograph TM84-5 on conductivity.
Ink not fully dried. Refer to INADEQUATE DRYING section of this guide.
Poor paper coating inergrity. Consult paper manufacturer.
Roughness of paper surface creates poor rub between unprinted paper surface and printed paper surface. ( i.e. some dull coat type stocks.) Consult ink manufacturer to provide ink with better rub resistance.
Too much ink. Lower level of ink carried.
Ink is not properly formulated for rub resistance. Consult ink manufacturer for adjustment.

Problem

Cause

Solution

SCUMMING
The non - image area of a lithographic plate accepting ink random area.
Low alcohol or alcohol substitute content in dampening system. Bring alcohol or alcohol substitute content of correct concentration. 2. 3.4.5.6.
Glazed blanket ink rollers, or dampening rollers. Clean thoroughly and recondition per manufacturer instructions.
Excessive printing pressure. Make on - press adjustment to proper pressure.
Ink spreading in to non - printing area. Consult ink manufacturer to assure ink is on - standard reformulate if necessary.
Plate improperly exposed to light after allowed to try. Desensitize or remake plate.
Improper ink/ water balance. Refer to INK/ WATER BALANCE. Section.

Problem

Cause

Solution


ROLLER STRIPPING

Rollers do not except ink.

Fountain solution too acid.

Check pH/ conductivity and gum concentration levels of fountain solution. Refer to flint ink corp. Technical Monograph TM 84-5 on conductivity.
Too much water being run. Reduce dampener setting.
Desensitized Mattel vibrator rollers. Clean rollers, copperas, wash thoroughly. Then ink rollers and wash again.
Glazed form roller. Remove rollers from press and deglaze as per manufacturer procedure. Rinse thoroughly.
Too much dampening solution being emuismed in ink. Consult ink and dampening solution manufacturer.

Problem

Cause

Solution

TINTING/ TONNING
Fine particles of ink adhering to non image areas of plate transmitted by press water dampener.
Ink bleeding in to fountain solution. Check concentration of alcohol or alcohol substitute in fountain solution. Consult ink manufacturer.
Improper fountain solution concentration. Check pH/ conductivity and adjust to proper concentration. Refer to flint ink corp. Technical Monograph TM84-5 on conductivity.
Too much pressure between plate and blanket. Check and re set to manufacture's specifications.
Improper setting of dampener or ink rollers. Check and re set to recommended manufacturer's specification.
Ink not sufficiently water resistant. Consult ink manufacturer.
Plate improperly exposed, developed. Check platemaking procedure; correct if necessary.

Problem

Cause

Solution

TRAPPING
Connot achieve good color balance or over all appearance.
Too much tack in relation to preceding ink. Consult ink manufacturer. Reduce tack of the ink that is not trapping properly.
Unequal press stability of inks. Ink tack up quicker than preceding ink. Consult ink manufacturer to adjust stability to be in line with previous color (s).
Ink strength not balanced properly. Consult ink manufacturer.
Inks contains additive that creates a film on top of it that will not allow succeeding ink layers to adhere to it when printed. Consult ink manufacturer.
Ink - water balance. Refer to MOTTLED SOLID section of this guide.
Poor ink release from blanket. Consult blanket and / or ink manufacturer.
Improper register causing poor appearance. Refer to MISTEGISTER section of this guide.

Problem

Cause

Solution

WEB BREAKS
Tearing of web as it travels through press - can occur infeed to cut - off to (1) paper defects, (2) press settings, or (3) ink.
Excessive tension on one or both edges of the web to loss of moisture and inkage. Keep rolls completely wrapped until ready to mount on roll stand. If the rolls are stored, make sure wrappings are undamaged.
Roll has dent or cut in end. If the dent is not deep, send or cut it out until edges of the paper are smooth. If the dent is deep, print down to the dent, stop the press, slab off the damaged portion of roll, resplice, and resume printing. If rolls are too badly damaged. Consult paper manufacturer.
Fiber cuts, hair cuts, wire holes, wrinkles, slime spots, foam spots, calendar cuts - any one of these can start a tear. If defects are numerous consult paper manufacturer.
Bad mill splices. If problem is extensive. The paper mill should be contacted.
PRESS :  
Web tension set too high. Decrease web tension.
Printing units or other press elements may be out of line. This is indicated if a proportionately large number of web breaks occur in one section of the press. An indication of misalignment of press elements is the presence of diagonal wrinkles in any span of web in the press. INK :
INK:
Have the press alignment checked and corrected if necessary.
Printing tack of ink is too high causing web to adhere to blanket and follow it causing a tear and subsequent web break. Consult ink manufacturer.
Body of ink is too long allowing drippage from fountain nip on to web below. Web will follow blanket causing break. Consult ink manufacturer.
Pigment strength of ink is too low causing ink fountain keys to be opened up too much. As a result ink will drip through ink fountain nip on to web below. Web will follow blanket causing break. Consult ink manufacturer.
Ink slinging. Consult MISTLING/ SLINGING section.

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