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Harnessing the Power of Electronic media for the Print media

 
Heading Problem Solution

Drying too fast

 

 

Drying too fast on rollers - rollers  

 

 

get tacky and this creates possible

Too much drier in ink.

Consult Ink Manufacturer.

picking and tacky  poor, uneven 

   

print which becomes worse with 

Too fast type of solvent used in ink

Consult Ink Manufacturer.

continued running.

and solvent is evaporated or absorbed

 

 

by rollers.

 

 

 

 
 

Rollers set too tight, generating

Adjust rollers to proper

 

excess heat or roller train.

pressure.

 

 

 

 

Press room too hot.

Improve air circulation in

   

press room.

     
Drying too slow    
     
Drying too slow- conventional inks do    
not dry in 4 to 8 hours and prints Not enough drier in ink. Add proper drier to ink
mark and rub easily.    Consult to Ink Manufacturer.
     
  Too much anti-oxidant in ink. Add drier and good drying  
    vehicle.  Consult Ink
    manufacturer.
     
  Too much non-drying oils or   Consult Ink Manufacturer.
  compounds in ink.  
     
  Stock too acidic. Test stock for drying
    properties before running
    Add drier stimulator to 
    water.
     
  Stock contains excess moisture. Use heater on delivery or
    store stock in warm place
    prior to running.
     
  Fountain solution is too acidic. Correct pH of fountain
    solution.
     
  Driers absorption in ink on aging. Add driers to ink replace
    lost driers.
     
  Ink taking up too much water and Consult Ink Manufacturer.
  emulsifying.  
     
     
     
Piling    
     
Pilling- ink piles on rollers, plate or       
to blanket and fails to transfer  Ink is too short, not water-repellent  a.  Add a varnish that will 
properly the substrate. enough. lengthen the ink and
    improve water resistance. 
    b.  Reduce dampening water
    to a minimum.  Add some
    alcohol to fountain solution.
    c.  If this does not help,  
    remake ink with more
    water-resistant varnish.
     
  Ink is poorly ground.  Particles are  Have ink reground.  Consult 
  transferred and build on rollers, plate Ink Manufacturer.
  and blanket.  
     
  Excessive use of heavy opaque  tend  Use a more transparent ink.
  pigment in ink, the particles of which  
  to pile.  
     
  Too much water and ink being carried  Cut down on water and ink
  ink to emulsify. feeds to obtain a proper
    balance.
     
  Stock coating adhesive is too water   a   Press size paper with
  soluble and coating is softened by transparent white ink
  first units and coating is then picked b   Change to a better
  up on the blanket of later units. paper.
     
  Ink tacks up too rapidly on the stock  Add alkyd to ink to slow 
  and piles on later units blankets. down setting.
     
     
     
Mottling    
     
Mottling- solid areas appear,  type     
or grainy. Pinholes of white paper Too much water. Reduce water if possible.
specked  showing through.  Edges of    
slurred and uneven. Too much water in a prior unit. Reduce water on prior unit if
    possible.
     
  Weak stock or paper coating is too Reduce with proper reducer
  soft. and reduce press speed if
    necessary.
     
  Improper pressure between blanket and Reduce pressure to minimum
  stock (excessive). between blanket and stock.
     
  Loose spots in paper coating. Change stock or press size
    sheets.
     
  Blanket too hard. Change to a softer blanket.
     
  Insufficient water at the plate. Increase water if possible.
     
  Ink too strong and insufficient ink is Weaken ink to allow more 
  being carried. ink to be carried on sheet.
     
     
     
Image Sharpness    
     
Sharpness of image- image    
working too sharp.  (Wearing of   Ink too tacky. Reduce tack.
plates).  Fine lines and dots tend to    
disappear.  Print loses clarity, Fountain solution is too acidic. Check pH and adjust if 
litho   printing becomes weak and   necessary.
streaked.    
  Ink sufficiently water-repellent and Add water-repellent varnish
  washes out. to ink.
     
  Pressures between plate and blanket Reduce pressure to minimum
  too heavy. between plate and blanket.
     
  Improper form roller setting. Check and reset form rollers.
     
  Starving Plate of ink. Weaken ink and carry more 
    to protect image.
     
  Poorly ground ink wears plate. Have ink reground.  Consult
    Ink Manufacturer.
     
     
     
Hickies    
     
Hickies- defects in a print    

appearing as specks surrounded

Particles of dried ink skin or drier mixed Only remedy is prevention.
by an unprinted halo.  Caused by into ink due to careless ink making or   
particles of dried ink, particles from careless handling in press room.  
decomposing rollers dirt, plaster, or    
accumulation of paper dust. Paper dust and spray powder  Good housekeeping around
  contaminating ink on rollers. the press is essential.  Clean
    the feed board and delivery
    grippers frequently to   
    spray remove paper dust 
    and powder. Use hot water 
    wash-up on rollers and 
    blankets.
     
     
     
Ghosting    
     
Ghosting- image patters appear    
in solids.  Ink is removed from roller  Poor distribution of ink. Ensure ink has good flow. 
by image in front of a solid and ink    Add alkyd varnish to improve
cannot be replaced or redistributed    flow.
prior to print solid.    
  Ink over-pigmented (too strong). Avoid running colors too
    heavy to produce tints. 
    Make ink weaker and run
    more of it.
     
  Faulty roller setting or poor rollers. Check rollers setting and
    adjust if necessary.
     
  Ink too transparent. If possible use opaque inks
    rather than transparent 
    inks.
     
  Poor layout of solids. Whenever possible make
    layout with solids well
    distributed.
     
     
     
Scumming    
     
Scumming- scum forms on plate.      
Hard to keep non-image areas   Ink too soft and spreads over Add heavy bounded get - 
clean. Non-image areas pick up ink.   non-image, sensitizing it. varnish to ink.  Consult ink 
Thickening of images.  Filling in of   manufacturer.
halftones.    
     
  Too much ink being carried and being Carry less ink and use a
  squashed over the non-image areas, strong ink if required to
  sensitizing those areas. achieve color density.
     
  Insufficient acid or gum in fountain  Strengthen fountain solution.
  solution.  
     
  Faulty plate.  Not opened properly.  Re-etch and gum plate on 
  Plate does not desensitize. press.
     
  Dirty or worn dampener covers. Clean or re-cover dampening 
    rollers.
     
  Wear of plate due to abrasive material Change to a better paper. 
  from the paper on the blanket.  Reduce plate-to-blanket
    pressure to minimum.
     
  Abrasive pigment particles in ink. Have ink reground or 
    replace with a better ink.  
    Consult Ink Manufacturer.
     
  Plate being sensitized from image off  a. Re-etch & gum scumming 
  previous units. plate.
    b.  Increase acid & gum on
    problem plate.
    c.  Run ink more sparely on
    preceding units.  If 
    necessary, use stronger
    inks.
     
  Greasy metering roller in Dahlgren type Clean rollers.
  dampening system.  
     
  Ink is not sufficiently water-resistant Add water-resistant varnish.
  and is broken down by fountain   
  solution.  
     
  Improper dampening setting. Reset dampeners to proper
    setting.
     
  Improper form roller settings usually Check stripe on plate and
  causes a lead-edge scum line across adjust if necessary.
  the plate.  
     
     
     
Tinting    
     
Pigment breaks down in the    
fountain solution causing a light Ink is too low in viscosity to carry the Add a high viscosity
discoloration of the non-printing  pigment. water-resistant varnish to
areas.   the ink.
     
  Ink is not litho resistant. Add a high viscosity 
    water-resistant varnish to
    the ink.
     
  Pigment is hydrophilic and bleeds in Reformulate ink with alcohol
  water. resistant pigments.
     
  Pigment bleeds in alcohol (Dahlgren). Reformulate ink with alcohol.
     
  Too much acid in fountain solution. Check pH pf fountain 
    solution and reduce acidity 
    of necessary.  Reduce  
    amount of solution if
    possible.
     
  Fountain solution is extracting an Change paper.
  emulsifier or sensitizing agent from the  
  paper coating. Proof: substitution of  
  another paper stops the tinting.   
     
     
     
Chalking    
     
Chalking - ink is dry but rubs off    
easily under a little pressure. Vehicle is too low in viscosity. Add good drying, high
    viscosity binder.
     
  Insufficient binder in ink. Add good drying, high
    viscosity binder.
     
  Stock is too porous. Add good drying, high 
    viscosity binder.
     
  Ink dries too slowly. Add good drying vehicle.  
    Add proper driers to the ink.
     
  a. too much anti-oxidant. a.  Add good drying vehicle.  
    Add proper driers to the ink.
     
  b.  Lack of driers. b. Add good drying vehicle.  
    Add proper driers to the ink.
     
  c.  Poor drying vehicle. c. Add good drying vehicle.  
    Add proper driers to the ink.
     
  d.  fountain solution is too acidic. d.  Adjust pH of fountain 
    solution to above 4.
     
  e.  paper is too acidic. e.  Add drier stimulator to 
    fountain solution and
    increase driers in  ink.
     
  f.  too much fountain solution stock  Cut back amount of water
  or moisture content of stock is too carried if possible, and use
  high. heater in delivery if possible,
    always store stock in a dry
    location.
     
     
     
Poor light fastness    
     
Color fades out when exposed to    
light.. Fugitive pigment used in ink. Use permanent inks when 
    light fastness is required.
     
     
     
Set-off    
     
Set-off (Offsetting)- ink    
transfers or smears from printed Too much ink carried Use stronger ink
side of sheet to reverse side in    
delivery pile. Ink sets too slowly on stock Use a heater to speed up
    setting Consult Ink
    Manufacturer
     
  Stock is too hard and solvent Increase amount of spray
  penetration is too slow powder
     
  Faulty spray settings- insufficient Correct spray unit if
  spray being carried.  Uneven coverage necessary
  of spray  
     
  Lifts stacked too high Reduce size of lifts or
    increase spray. Run Sheets
    into trays
     
  Rough handling of printed stock or Handle printed stock
  sheets.  Poor jogger settings carefully; reset jogger so
    that sheets do not side
     
     
     
Rub Resistance    
     
Rub Resistance (Poor)- ink is dry, Ink has only a surface dry and not a Consult Ink Manufacturer.
but has poor adhesion under rubbing  complete through dry.  
pressure.    
  Ink contains insufficient wax to Consult Ink Manufacturer.
  promote slip required to give rub.  
     
  Not enough binding varnish in ink for the  Add additional binder 
  stock run. required for particular stock.
     
     
     
Stripping    
     
Stripping- the rollers accept the    
ink unevenly and areas appear Rubber rollers are glazed. Deglaze rollers with glaze
which are stripped of ink,   remover.  Wash - up 
starving the plate of ink in those    thoroughly and use hot
places.   water for final wash-up.
     
  Steel or copper rollers have become a.  Copperize copper rollers
  preferentially wetted by the aqueous b.  Strip the steel rollers and
  etch and repel the ink from the area. dry well before re-inking.
     
  Ink is too heavy and short and has  Add alkyd varnish to ink to
  poor distribution. improve flow and distribution.
     
  Ink is too strong. Reduce strength and run 
    more ink.
     
  Too much water being carried on plate. Reduce dampener flow.
     
  Too much acid in fountain solution. Adjust to proper pH.
     
  Ink takes up too much water. Add water-resistant varnish.
     
  Ink does not emulsify properly. Consult Ink Manufacturer.
     
     
     
Trapping    
     
Trapping- poor in multi color wet Too much ink carried on first down    Make first down colors as   
printing.  last colors do not transfer  run colors. Underneath ink-film is too strong as possible, carry
properly to the first colors. heavy.  Underneath colors should never very thin films. (Thin films
  heavier than succeeding ink colors. trap better than thick films.)
     
  Tack sequence out of balance. First   Adjust to proper tack 
  down colors should be tackier than last sequence.
  down colors.  
     
  Unequal tack stability of quick set inks. Add alkyd to the unstable 
  One ink tacks up quicker on rollers ink to stabilize its tack on
  than the previous color. the rollers.
     
     
     
Slurring    
     
Slurring- shadow dots and reverse     
letters fill up. Caused most frequently by slippage  Correct poor press  aided  
  between cylinders or press. condition. Problem can be
    using a stronger and heavier
    by  ink, but this only masks
    the problem.
     
  Oil on bearers. Correct poor press condition.
     
  Over packed or under-packed cylinders Correct poor press condition.
     
  Slurs that show a double dot in   Correct poor press condition.
  halftones indicate improper press  
  adjustment.  
     
     
     
            

 

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