Gold ink printing common fault handling

In the printing process, gold ink is often used, gold can play a role in finishing touch, but gold ink's adsorption and transferability is worse than the general ink, so in the printing process will encounter many problems and produce various Quality instability factors. When using gold ink, first adjust the printability of gold ink, pay close attention to the transfer effect of gold ink in the printing process, the operating speed of the printing press should not be too fast, and the transfer roller should always be in the best condition. It will help the ink to transfer to the surface of the printing plate and substrate intact and evenly. Get better results.

There are many quality defects encountered in the printing process of gold ink, which are mainly reflected in the dullness of the print, the enlargement of the print, the stencil, and the imprint of the ink.

Imprint

1 Chemically unstable. When golden ink is exposed to moisture, heat, contact with acid and alkali, or exposed to the air, it is prone to chemical reactions, causing gloss damage and darkening and lack of brightness. Therefore, gold ink should be protected from heat, moisture, and exposure during storage, to avoid contact with acid-base substances.

2 The printing machinery is not clean. In the printing process, the ink is accelerated by the high speed of the ink roller for a long time, which accelerates the oxidation rate of the gold ink and causes the ink to deteriorate. Under normal circumstances, for every 4 hours of continuous operation of the printing press, the rubber roller (offset including the water roller) must be thoroughly cleaned once and then replaced with a new ink to keep the ink fresh and shiny.

3 Proportioning ink storage time is too long. Gold ink deployment, should be less to adjust, generally kept in the amount of 3-4 hours as well, equipped with the time and the use of gold ink separated by time prone to oxidative deterioration, dark color, thereby affecting the product's gloss.

4 printing materials poor smoothness. The printing material is poor in smoothness and has a rough surface. The gold ink is permeated into the middle of the fiber immediately after it is transferred to the surface, causing the surface of the ink layer to lose luster.

5 The speed of the machine is too fast. The speed of operation of the machine is too fast, and the heat generated by friction is too high, which accelerates the oxidation of gold ink and loses its luster. Therefore, when printing gold ink, the machine speed is slower than that of other colors.

Imprint expansion, paste version

1 Insufficient ink volume. The amount of ink output by the ink fountain is excessive, resulting in an excessively thick ink layer on the surface of the ink roller. Transferred to the surface of the printing plate, the graphic part can't bear the excessive ink, under the effect of printing pressure, it will inevitably extend to the edge of the printing, or the phenomenon of pulling ink and stencil printing occurs. It is found that the ink volume is too large or the ink is too sticky. To control the amount of ink, remove the excess ink on the surface of the ink roller, and then print evenly.

2 printing pressure is too heavy. Improper adjustment of the machine pressure or due to wrong method of pad printing will cause the mechanical pressure to be too heavy, the pressure is too heavy, and the ink mark on the graphic will expand to the edge, and even paste. The pressure must be readjusted.

3 Drying is too slow or the product is too thick. Due to the slow drying of the ink, the finished product is too thick to accumulate, the gravitational force causes the imprint to expand, and the stencil is even dirty; during operation, an appropriate amount of desiccant should be added to the ink, and the stacking should not be too thick.

The imprint is missing and exposed

1 Print materials have poor smoothness. The printing material is poor in smoothness, rough and uneven surface, easy to make the graphic ink layer exposed, the imprinting is not smooth. Ink is uneven. Proper ground color processing, increased printing pressure and ink volume, can improve the quality of gold ink imprinting.

2 The printing pressure is not ideal. The printing pressure is too light or uneven, causing the graphic ink layer to be uneven: the ink layer floats on the surface of the printing material. The golden ink particles are relatively coarse, so that they can be smoothly and evenly transferred to the surface of the substrate. They must be compacted and pressed flat, and the pressure should be properly increased to make it uniform and solid. This can avoid the occurrence of defects such as the occurrence of false markings and exposed bottoms. In the case of thick lines, overprinting or two printing methods are usually used to solve the phenomenon of hairlessness.

3 ink roller poor adaptability. The roundness of the ink roller is uneven, and the flexibility, viscosity and elasticity are poor, so that the gold ink cannot be transferred to the surface of the printing plate and the substrate in a good manner during the transfer process. The ink layer of the graphic is not full and affects the printing quality. Before the printing, all the ink rollers should be properly maintained, and maintain a good printability, so as to create conditions for improving the printing quality of gold ink.

4 ink layer is not uniform. The gold ink is overly thinned, the consistency is poor, the effect of the green jade is poor, the ink supply is uneven, and the ink layer is too thin, which affects the quality. In the printing process, the dilute consistency of the gold ink is adapted to the printability. Keep the ink layer in a uniform state to prevent the prints from becoming imaginary and exposed.

Source: China Ink Technology Network