JUJO TECNICAL INFOMATION

Jan, 2001

HOW TO SOLVE THE PROBLEMS OF PAD PRINTING

Problems Conditions Causes Countermeasures
Defective pattern Ink remains on the plate. (1) pad is new. Wipe the pad with solvent-soaked cloth.
(2) pad is too soft. Substitute the pad with the harder one.
(3) Ink is too viscous. Add thinner to lower viscosity.
(4) Ink dries too fast. Use thinner of slow dry type.
(5) Unsuitable thinner. Use designated thinner.
Blotting, Unevenness of solid color Ink remains on the pad after printing. (1) pad is too hard. Substitute the pad with the softer one.
(2) Too much thinner. Add ink.
(3) Ink dries too slowly. Use thinner of fast dry type.
(4) Printing speed is too fast. Slow down the printing speed.
(5) Attrition of the pad.
(Max: 30,000-50,000 times)
Replace the pad with the new one.
Misting A pattern is spoiled by thread-like ink. (1) Static electricity. Raise humidity in the printing room.
(2) pad rises too fast. Slow down the rising speed.
(3) The shape of pad is unsuitable. Replace the pad with the pointed one.
(4) Ink is too viscous. Add COMPOUND.
Pinholes Foam appears at the edge of the pattern. (1) ttrition of a blade.
(Max: 5,000-30,000 times)
Replace the blade with the new one.
(2) blade is stained. Clean the edge of the blade.
Crawling. (1) Too much thinner is added. Add ink.
(2) Printed surface is stained. Clean the surface with alcohol, etc.
(3) jLevelling agent is not enough. Add levelling agent.
Distortion A pattern is distorted. (1) pad is pushed too strongly. Push the pad lightly.
(2) Printed material is not fixed. Check the receiver of the material.
Poor adhesion Fail in scotch tape peeling or nail scratching test. (1) Choice of ink is wrong. Choose suitable ink for the material.
(2) Insufficient drying or curing. Dry or cure completely.
(3) Printed surface is stained. Clean the surface with alcohol, etc.
(4) Density of ink is too high. Use ink of lower density.
Poor physical properties Poor resistance to abrasion or solvent. (1) Choice of ink is wrong. Chooose correct ink series.
(2) Insufficient drying or curing. Dry or cure completely especially in case of two-component type.
(3) Ink film is thin. Deepen the etching of the plate or print two or three times.
Poor opacity Base color shows through ver-printed ink. (1) Opacity of ink is insufficient. Choose high-opacity ink.
(2) Ink film is too thin. Deepen the etching of the plate or print two or three times.
Low gloss Finish is matt. (1) Choice of ink is wrong. Choose the gloss type of ink.
(2) Two-pack type of ink exceeds its pot life. Replace the ink.
(3) Unsuitable thinner. Use designated thinner.
Poor stability of color-matched ink Density or color shades change during print or storage. (1) Ink is color-matched with the different series of inks. Match colors with the same ink series.
(2) Unsuitable thinner. Use designated thinner.