This article is a speech made by Mr. Jack Knight on behalf of the United States INX in the "2008 Metal Packaging International Forum" technology exchange conference organized by the China Packaging Federation Metal Container Committee in Zhuhai. The advantages and popularization of transforming the traditional Indian iron production line into UV printing iron and UV printing have strong practical significance and are worthy of our consideration and reference.
When comparing the curing methods of the two inks, you will see great help in quality improvement and cost savings. Here are some suggestions and tips before you run.
There is no specific order here. First, the advantages of UV technology in metal printing:
1. Space-saving A UV ink-cured production line takes only about 3 meters in length, whereas a conventional gas oven curing line requires 30 meters in length.
2. Operation cost The production line using UV ink only needs electricity and the power used by UV line is the same as the power used in the traditional production line. Naturally, it saves gas consumption, but also saves the maintenance of the oven and related spare parts, etc. cost.
3. Pollution aspects UV lamps used in UV production lines produce only small amounts of ozone and quickly convert to oxygen without affecting the surrounding environment.
4. Production Operations The use of a UV line cure shortens the time it takes to see the results. Print results are immediately visible within 10 minutes and the next step can be performed immediately.
5. Immediate availability The UV line can be produced immediately without preheating. The UV lamp can be turned off before preparation or changing the plate. The traditional line needs to be warmed up before production.
6. Emissions In the process of using UV production lines, ozone will be produced, but it will be converted into oxygen in a short period of time, so it is not necessary to consider the issue of emissions.
7. Human resources The use of UV rays only requires the printing operator, who does not need to operate the back of the oven.
8. Maintenance and faults UV line design is relatively simple, there is no oven door and flower iron frame, saving time and costs, can completely avoid the impact of drying racks to the product quality. If the UV lamp does not meet the requirements, it can be replaced after low-speed production. However, when the conventional line is in trouble, it must be shut down for maintenance and the replacement of flower iron racks or flower iron racks, and the dirt on the conveyor chain should be regularly cleaned.
9. Ventilation system Because the UV line does not consume much oxygen when it is cured, it does not need to replenish a lot of fresh air, especially in the winter, it will save energy for heating.
Second, the use of UV benefits
1. Use of Ink and Cleaning Agents Since UV inks cure only in the UV band, UV inks require better control of the amount of ink, which saves cleaning agents and ink.
2. Excessive control points Because of the overlapping of colors in the printing process, the use of UV-rays produces a dry-to-wet printing that can better control the diffusion of dots than wet-to-wet printing of conventional threads.
3. Better arrangement of overprinting Because traditional lines are used for wet-to-wet printing, the viscosity and ordering of the inks should be taken into account when overprinting, while the use of UV-rays is dry-to-wet printing so these factors need not be considered.
4. Reducing production steps The use of UV printing makes it easy to arrange overprinting, which can greatly increase production efficiency and reduce scrap rate.
5. What changes are needed to change the UV line Fountain solution Transfer roller Blanket Cleaning agent
Third, the need to increase the cost of UV
1. Initial capital investment cost
2. Higher cost of UV inks
3. UV lamp has only 2000 hours of service life
4. The aluminum reflection plate of UV lamp needs to be replaced with 6000--7000 hours
5. The use of advanced dampening system can better achieve the balance of ink and ink separation
Fourth, if you consider changing the UV line can choose:
1. Buy a new UV production line
2. Change the existing production line to UV line. When changing the existing production line, it is necessary to adjust the transfer roller, blanket, cleaning solution and dampening plate to meet the requirements of UV ink.
V. Suggestions after using UV rays to summarize printing experience
(a) Cleaning
1. Use only solvent-based cleaning solutions for UV printers.
2. No washing residue remains on the blanket, plate, transfer roller.
3. Use with UV wash solution and IPA (isopropyl alcohol).
4. If any solvent remains on the plate, the transfer roller, and the blanket will affect the ink transfer and curing.
5. Keep the plate cylinder clean.
(B) Mixed fountain solution
1. Keep the conductivity at 1800-2800.
2. Keep the fountain pond clean without any build-up and residual emulsification.
3. Add only deionized water to the fountain pond.
(3) Balance of water and ink
1. Keep the amount of water at a minimum level because UV inks are susceptible to water.
2. If the water level is not properly controlled, it will affect the curing effect of the ink, because the softening and curing of the ink after water absorption will not produce the phenomenon of anti-printing.
3. Keep the sprinkler system clean and properly set up.
4. Maintain a uniform amount of ink (using a densitometer).
(d) Curing and power settings
1. Use the lowest power possible to achieve the curing effect.
2. Normally transparent inks can be cured with low power, opaque white inks require high power, darker inks require higher power to cure.
3. Try to use the minimum amount of ink to reach the standard, while having a good ink balance.
4. Keep the average amount of ink (using a densitometer) and set the UV lamp power at the same time.
5. If you need to use a larger amount of ink to achieve the standard, you must increase the power of the UV lamp, and at the same time contact the ink supplier can improve the ink.
Picture article:
Appendix : Appendix
UV CURING UV Curing Thermal Drying Heat Curing UV UV Heat Heating
Liquid Solvent Solvent
Coating Liquid Coating Substrate Substrate
Oligomers Monomers & Photoinitiators
Photofining agent
Substrate substrate