The core component of a UV printer is undoubtedly the UV print head, commonly known as the nozzle. For printing enterprises, the "nozzle clogging" phenomenon of UV printers occurs from time to time, which is really distressing for users. Leaving the printer unused for a long time can cause clogging, improper operation can cause clogging, and using poor quality ink can even cause clogging! It seems that nozzle clogging is quite troublesome!
If not repaired in time, it will not only affect the production progress, but may also cause permanent clogging, rendering the printer useless. If you need to replace a nozzle, the cost will be high! Therefore, it is particularly important to master the proper skills. Daily maintenance can reduce clogging issues, and enable you to deal with emergencies easily!
The main causes of UV printer nozzle clogging include improper sealing after normal printing or prolonged inactivity, leading to excessive evaporation of moisture. This causes ink particles to dry and accumulate on the delicate tip of the print head, preventing normal ink ejection. Additionally, mixing different types of inks can cause chemical reactions, typically resulting in issues such as line breaks, color loss, blurred text, or even complete printing failure.
We all know that a UV flatbed printer costs anywhere from tens of thousands to hundreds of thousands of yuan. The most important part of the entire machine that requires maintenance is the nozzle. Nozzle clogging is one of the common problems. First, we need to understand the causes of clogging to address the issue at its root!
Common causes of UV flatbed printer nozzle clogging:
1.【Bubble-induced Clogging】
Poor defoaming performance of UV ink causes bubbles to form in the ink. Once these bubbles enter the nozzle, they are difficult to remove, resulting in air blockage.
2.【Particle-induced Clogging】
Tiny particles in UV ink enter the nozzle and block the narrow ink outlet channel.
3.【Filter Clogging】
Impurities and harmful solvents in low-quality UV ink get trapped in front of the filter, causing clogging over time.
4.【Drying-induced Clogging】
Leaving the nozzle unused for an extended period causes ink to dry up, resulting in clogging.
5.【Chemical Reaction Clogging】
Using UV inks of different properties causes chemical reactions that produce impurities, leading to clogging.
6.【Degradation Clogging】
Occurs in high temperatures when bacteria breed in UV ink, causing ink degradation and formation of impurities inside the nozzle.
7.【Scaling Clogging】
UV ink with excessively high mineral content, when used long-term, causes scale buildup in the nozzle, reducing the effective diameter, often starting with horizontal streaks in printing.
8.【Oil Contamination Clogging】
UV print carts require lubricating oil, which can vaporize and spread to the nozzle, altering the physical properties at the nozzle opening and causing clogging.
9.【Electrical Clogging】
Nozzles with ink or cartridge chip electrical detection may partially close ink valves when non-standard ink or chips are used, preventing normal ink flow, known as false clogging.
10.【Dust Clogging】
Exposed nozzles attract dust particles from the air, which adhere to the nozzle and cause clogging.
In general, UV printer nozzle clogging can be roughly categorized into soft clogging and hard clogging, each with different solutions. Now that we understand the causes, let's look at the solutions:
Soft clogging refers to line breakage caused by increased ink viscosity on the nozzle for various reasons. Sometimes, it only adheres to the surface of the ink outlet. It can generally be resolved by applying cleaning fluid and performing multiple cleanings.
Advantages: Simple and quick operation without any physical damage;
Disadvantages: Higher usage cost and more waste of cleaning fluid.
Note: The above method should generally not exceed three attempts. For minor clogging, three attempts should clear it. If unsuccessful after three tries, the clogging is more severe, and additional cleanings will likely be ineffective while wasting expensive cleaning fluid. In such cases, further treatment is needed based on specific conditions.
Hard clogging refers to blockages caused by chemical deposits or impurities inside the nozzle. This malfunction is more difficult to resolve and can be addressed using the following methods:
1. Soaking Method
Applicable range: Mild clogging situations.
Necessary tools: Cleaning fluid, a clean cup, and a flat-bottomed metal container;
Working principle: Using a medium-strength organic solvent to dissolve ink particles one by one. Note that cleaning fluid must be used, otherwise it may cause more harm than good.
Solution: Find a flat-bottomed metal container, add a small amount of cleaning fluid, enough to submerge the stainless steel edge of the print head (be careful not to let the PCB board come into contact with the cleaning fluid). Soaking time generally ranges from 2 hours to 4 days.
Advantages: Good cleaning effect and unlikely to cause physical damage to the print head;
Disadvantages: Requires a long time, not suitable for urgent situations.
2. Distilled Water Cleaning Method
Applicable range: Severe clogging situations.
Necessary tools: A decoded empty cartridge, a disposable syringe, and a bottle of medical distilled water (purified water can also be used as a substitute).
Working principle: Similar to the pressure cleaning method.
Solution: Prepare a decoded empty cartridge, a disposable syringe, and a bottle of medical distilled water. Use the siphon pressure from the syringe to inject distilled water into the cartridge through the ventilation hole. After a while, extract the distilled water with the syringe. Repeat this process multiple times to thoroughly clean the remaining ink in the cartridge.
3. Ultrasonic Cleaning Method
Applicable range: Most severe clogging situations.
Working principle: Using an ultrasonic cleaner to generate strong ultrasonic waves that cause intense vibration of water molecules, breaking down tiny dried ink particles and dissolving them in water to achieve cleaning purposes.
Solution: Gently place the UV printer head into the cleaner, add purified water or special print head cleaning fluid, enough to submerge the stainless steel edge of the print head (be careful not to let the PCB board come into contact with the water or cleaning fluid). Turn on the machine for 10 to 15 hours for thorough cleaning.
Advantages: Excellent cleaning effect, can clean print heads that have been blocked for years, and operation is very simple;
Disadvantages: Higher maintenance cost and relatively expensive equipment.