Backing - Constant film weight be maintained on print, ink does not follow duct rollers.

• SOLUTION:

1. Ensure there is sufficient ink in the ink duct
2. Add flow improving varnish to the ink max 5%

Chalking - Ink pigment does not bind to the stock and comes off by mere rubbing.

• SOLUTION:

1. Use less absorbent paper
2. Ensure fountain pH is between 4.8 to 5.5
3. Use higher quality ink (stronger and fast setting)
4. Use O.P. varnish to save printed sheets

Dot Gain/Muddy Halftones - Halftone dots increase in size causing the printed matter to lack sharpness.

• SOLUTION:

1. Reduce ink release
2. Check reproduction process/plate/blanket
3. Ensure proper ink-water balance
4. Check pressure between from roller to plate to blanket to paper
5. Use stronger ink

Emulsification/Tinting - Light tint appears on un-printed parts of stock and water marks spoil printed areas.

• SOLUTION:

1. Maintain proper ink-water balance
2. Clean/check plate, correct if necessary
3. Ensure fountain pH is between 4.8 to 5.5 

Fading - Print changes strength or color with time.

• SOLUTION:

1. Check paper stock
2. Use Light-Fast Inks in case of outdoor exposure

Gloss(Low) - Less gloss/reflection from printed image.

• SOLUTION:

1. Use smoother paper
2. Reduce fountain solution feed
3. Increase ink film thickness slightly
4. Use glossy ink

Hickies - Blemishes in the printed ink film, specially for solid image area.

• SOLUTION:

1. Ensure there is no skin while putting ink into ink duct
2. Clear rollers and blankets to remove dried ink
3. Inspect press room and press for cleanliness to avoid dust/contamination
4. Use paper having good pick strength to avoid fluffing

Mileage - More ink is consumed per impression than normal.

• SOLUTION:

1. Adjust color densities to optimum with satisfactory print quality
2. Maintain proper ink water balance
3. Use stronger ink

Misting/Flying - At high machine speed, a spray/fog/mist is visible in the air which finally covers entire parts of the press.

• SOLUTION:

1. Use stronger ink with lower release
2. Check roller settings
3. Release optimum fountain solution
4. Reduce the printing speed
5. Add Tack Reducer at Max 5%

Picking of Paper - Particles torn from papers, paper coating, scattered at irregular places.

• SOLUTION:

1. Use paper having good pick strength
2. Use less tacky blanket
3. Check print pressure
4. Reduce machine speed
5. Add Tack Reducer at Max 5%

Plate Wear Off - Loss image area meaning successive impression becomes weaker and weaker, especially common in long run jobs.

• SOLUTION:

1. Re-adjust the pressure of ink form roller and damping form roller
2. Check/reduce plate to blanket pressure
3. Check quality of plate
4. Ensure fountain pH is between 4.8 to 5.5
5. Consult the ink manufacturer to check grinding

Roller Stripping - Steel rollers do not accept ink and remain blank at certain areas.

• SOLUTION:

1. Reduce damping solution feed
2. Ensure fountain pH is between 4.8 to 5.5
3. Clean the rollers and copperize if required

Rub Resistance/Scuff Resistance(Poor) - Printed ink film appears dry but gets smudged/transferred when rubbed.

• SOLUTION:

1. Reduce fountain solution feed
2. Ensure fountain pH is between 4.8 to 5.5
3. Use smoother paper
4. Print with optimum ink release
5. Consult ink manufacturer
6. Use OP varnish

Scumming - Ink patches showing on non-image areas on the print.

• SOLUTION:

1. Ensure fountain pH is between 4.8 to 5.5
2. Check plate wear off
3. Use stronger ink and run with reduced release
4. Correct inkers and dampers setting

Set-off - Ink marks appear on the back of the next sheet in the delivery file.

• SOLUTION:

1. Reduce ink release
2. Use high quality ink (Stronger and fast setting)
3. Reduce size of stacks
4. Use Anti-setoff powder in multi color printing
5. Add SN 8193 Liquid Drier at Max 2%

Slow Drying - Ink film remains wet or tacky to the touch.

• SOLUTION:

1. Avoid addition of any non-drying compounds
2. Avoid using highly acidic paper
3. Ensure fountain pH is 4.8 to 5.5
4. Avoid Excess fountain solution unto the plate
5. Add SN 8193 Liquid drier at max 2%

Trapping - Subsequent colors on multi colors job do not transfer properly, resulting in poor color balance.

• SOLUTION:

1. Check temperature of the ink rollers
2. Make sure inks are printed in decreasing tack order
3. Check ink release of subsequent colors
4. Maintain proper ink water balance
5. Check the strength and viscosity of ink by consulting ink manufacturer
6. Add Tack Reducer in subsequent colors at max 5%

Mottled print - The printed has mottled or flecked appearance, with colored or black circles usually appearing in the light colors.

• SOLUTION:

1. (CAUSE: Viscosity too low) - Add non-diluted ink and adjust the viscosity, change the plate.
2. (CAUSE: Surface of plate in poor condition) - Add Thickener.
3. (CAUSE: Pollution "anti-foam, silicon, etc.") - Carefully clean the plates, do not use materials likely to leave lint on.
4. (CAUSE: Fount roller or anilox in poor condition) - Check the condition of the roller, the wear on the anilox cylinder and check that the link cells are not blocked.
5. (CAUSE: Unequal absorption of the ink into the substrate) - Use softer plates or opaque inks.

Drying too rapid - The ink dries on the inking system (plate and cylinder) and hampers ink transfer.

• SOLUTION:

1. (CAUSE: Solvent based ink "the thinning solvent evaporates too quickly") - Use a solvent with a lower evaporation rate.
2. (CAUSE: Water based ink "in correct pH") - Add 2% to 3% of retarding solvent, add re-generator (1% to 2% every 3/4 hours.

Drying too slow - Lifting of the ink or marking of the feed rods, blocking in the spool, ink sticky.

• SOLUTION:

1. (CAUSE: Solvent based inks "Viscosity of the ink too high" the thinning solvent evaporates too slowly) - Reduce the viscosity with the recommended solvent.
2. (CAUSE: Water based inks "Viscosity too high") - Dilute with water or viscosity reducer (2% to 5%) incorporate re-generator (1% to 2%).
3. (CAUSE: Problem with drying tunnel) - Check the temperature and the extraction system.

Poor adhesion of the ink to the substrate - Poor mechanical resistance (poor rub, adhesive tape, scratch resistance, etc.).

• SOLUTION:

1. (CAUSE: Ink not adapted to the substrate) - Use a suitable ink or consult the supplier.
2. (CAUSE: Substrate incorrectly treated or treatment has passed its expiry date) - Check the surface tension of the substrate or consult the supplier to check the expiry date of the treatment. Check the possibility of applying a pre-lacquer varnish or primer varnish or use CORONA treatment.
3. (CAUSE: Insufficient drying) - Increase the drying temperature and if possible the air flow.

Print not intense enough:

• SOLUTION:

1. (CAUSE: Viscosity too low) - Add non-diluted ink or a concentrate.
2. (CAUSE: Anilox screen too fine) - Use an anilox with a coarser screen size.
3. (CAUSE: Anilox screen worn or blocked up) - Change or clean the anilox.

Print too intense:

• SOLUTION:

1. (CAUSE: Viscosity too high) - Reduce the viscosity with an appropriate thinner.
2. (CAUSE: Anilox screen too coarse) - Anilox screen too coarse.
3. (CAUSE: Doctor blade incorrectly adjusted) - Adjust the doctor blade so that it correctly wipes the cylinder.
4. (CAUSE: Color strength too high) - Adjust the doctor blade so that it correctly wipes the cylinder.

Poor ink transfer: The plate does not deposit enough ink unto the substrate.

• SOLUTION:

1. (CAUSE: Viscosity too low "drying on the plate") - Add non-diluted ink, adjust the drying of the ink.
2. (CAUSE: Surface tension of the substrate too low or surface tension of the plate too high) - Check the treatment of the substrate and the surface energy of the plate.
3. (CAUSE: Pressure between the plate and the anilox incorrectly adjusted) - Adjust the pressure settings.
4. (CAUSE: Anilox screen worn or blocked up) - Change or clean the anilox.
5. (CAUSE: Anilox screen too fine) - Use a coarse screen.

Viscosity increases in the ink duct:

• SOLUTION:

1. (CAUSE: Solvent based inks "unsuitable solvent or imbalance due to evaporation") - Add a more suitable solvent.
2. (CAUSE: Water based inks "Reduced pH") - Add re-generator (1% to 2%)

Ink not homogeneous: Particles in suspension.

• SOLUTION:

1. (CAUSE: Wrong additive incorporated, causing precipitation) - Filter the ink in the ink duct, check that the product used is compatible with the ink. And the additives slowly, while agitating.

Moire effect: Blurred four colors print.

• SOLUTION:

1. (CAUSE: Incorrect ratio between the screen ruling of the plate and that of the anilox) - Use an anilox roller adapted to the print run.
2. (CAUSE: Plate screens not at right angle) - The color separation films should be corrected.

Blocking in the reel: Spools stick together, making the prints unusable, print leaves marks on the underside of the substrate.

• SOLUTION:

1. (CAUSE: Ink not drying correctly) - Reduce the viscosity of the ink, change the thinning solvent to accelerate drying, change the balance of the thinners, increase the drying capacity and/or the volume of air.
2. (CAUSE: Substrate temperature too high before spooling) - Install a cooling system before the re-spooling.
3. (CAUSE: Spooling pressure too tight) - Reduce the spooling tension.

Prints  clogged up or slurred: Excess ink around halftone dots and small text and poor character definition.

• SOLUTION:

1. (CAUSE: Pressure between plate and anilox too high) - Adjust the pressure correctly.
2. (CAUSE: Inks dries to rapidly) - Adjust the drying of the ink.
3. (CAUSE: Ink viscosity too high) - Dilute the ink.

Streaking: Wide streaks across the print.

• SOLUTION:

1. (CAUSE: Worn gears) - Replace the worn gears.
2. (CAUSE: Excessive tightening of the inking cylinder) - Check the thickness of the plate "using a too thin plate compensated by excess tightening").