Sheetfed ink printing failure and countermeasures

1, ink fountain deinking:
phenomenon:
The ink is deinked (not grooved), the ink supply is reduced or interrupted, and the printed product becomes lighter in color.
the reason:
1, ink is too short, the flow is too small
2, thixotropy is too large, the viscosity is too small
1. Join the new liquid ink
2, adding a larger viscosity of the connecting material to increase the ink slope

2, pull paper hair:
phenomenon:
A small amount of paper will be pulled from the surface of the paper. Causes the printing product to be scrapped.
the reason:
<1> Too much ink viscosity
<2> Paper surface strength difference measures:
1. Add TPP-041 pull paper inhibitor to reduce ink stickiness.
2, the use of high surface strength paper.
3, reduce the speed of the printing press.

3, ink powder:
phenomenon:
After a little pressure, the ink is easy to rub off.
the reason:
<1> There are few film-forming materials in the ink
<2> Ink viscosity
<3> The ink is poor in water resistance (emulsification)
<4> The paper is too ink-absorbing
<1> Improving the composition of film-forming substances such as adding high-viscosity resin oils
<2> Reduce the acidity of the medicine to reduce the amount of water.
<3> Replacing Less Absorbent Paper

4, dry slowly:
phenomenon:
48 hours quit, the blot can easily be erased.
the reason:
<1> Insufficient drying agent in ink
<2> Ink resistance is not good
<3> Ink storage, the effect of desiccant becomes smaller.
<4> Too much amount of wetting powder
<1> Add an appropriate amount of desiccant to the ink.
<2> Improve ink water resistance.
<3> Adjust the pH of the medicine and reduce the amount of wetting powder added.
<4> Add TPP-002 printing syrup desiccant to the printing solution.

5, heap rubber:
phenomenon:
The ink accumulates on the blanket and does not transfer to the paper.
the reason:
<1> Ink is too short to resist poor ink emulsification
<2> There are too many pigments or fillers used in the ink.
<3> Paper Flake
<4> The amount of anti-adhesive agent added is too large.
<1> Reducing the amount of antifouling agent added
<2> Increase ink length and improve water resistance

7, ink roller heap:
phenomenon:
The ink on the roller cannot be transferred, the density of the printed sample is not enough, the parking water evaporates, and then the car is driven. The density exceeds the requirement.
the reason:
1, ink water resistance is not good,
2, ink ink is too short.
3, the ink viscosity is too small.
4, the amount of printing syrup is too large.
Countermeasures:
1, check the ink viscosity and fluidity
2, improve the ink resistance
3, reduce the amount of water or add isopropyl alcohol to improve the wettability, increase volatility.

8, from greasy:
phenomenon:
There is a layer of floating point on the layout is not clear.
the reason:
<1> Poor ink resistance
<2> Insufficient viscosity of ink.
Countermeasures:
<1> Increase the viscosity of the ink and add TPP-101 external oil.
<2> Adjust the printing solution, add isohexol or alcohol, and reduce the surface tension.

9, dirty version:
phenomenon:
Cannot keep the non-image part clean.
the reason:
<1> The ink is too soft and the viscosity is too low
<2> The pressure of the ink roller depends on the order of the pressure
<3> The plate is not sensitive enough
<4> Poor water resistance of inks:
<1> Add TPP-101 External Oil
<2> Adding Isohydrin to Water to Decrease Surface Tension or Increase Water Volume
<3> Check the surface of the dampening roller for good water absorption and oil removal
<4> Adjusting the pressure of the printing roller

10, flying ink:
phenomenon:
The droplets of ink droplets that form between the ink rollers are scattered around the machine and pollute the environment.
the reason:
1. The ink supplied to the ink roller is too thick or the ink film of the ink roller is not uniform.
2. The ink is too long or the viscosity is too small.
3, ink spoke wear damage, or improper installation.
Countermeasures:
1, reduce the amount of ink or adjust the ink roller pressure to make the ink film even.
2, adding wax additives to make ink ink shorter.
3, check the ink roller is damaged, the installation is reasonable.
4, reduce the printing speed.

Source: 21st Century Fine Chemicals Network