Solvent Printhead Blocked Reasons & Solutions

Reason of nozzle blocking:

• Ink qualitynot good, have impurities. ink cartridge quality not

SOLUTION: Use filter devices to avoid the impurities , use better ink and ink cartridges.

• The temperature and humidity change rapidly has a bad effect on ink and nozzle,which cause the blocked up.

The temperature and humidity of Storage and working environment has an effect on stability of ink, which lead to ink break or scattered or make ink dried on the surface of the nozzle etc. Temperature changes rapidly may easily break the balance of inner printhead and work abnormal , ink may also can’t use suddenly.

SOLUTION: Equip temperature adjustment device in the workshop, control temperature varies within 3-5 degrees.

• Printhead voltage has an effect on printhead .

Too low voltage of printhead will make affect the saturation of images, however, the high voltage may cause damage to the piezoelectric crystal inner head nozzle,cause frequently leakage ink,decrease the lifetime of printhead. Therefore ,do not make head voltage too high if not affect image quality.

Different brand solvent printers require different head voltages, high voltage will also require high ink viscosity.

When the voltage of the printhead is high but the viscosity of ink is low, will cause burrs and floating too much ink and too fast speed ink jetting, and block up the printhead etc.

When the voltage of the printhead is low but the viscosity of ink is high ,will cause no ink-jetting, saturation not good, non-uniformity etc.

SOLUTION: Change to appropriate ink or adjust voltage.

• Static electricity has an effect onSolvent printer and ink.

Must take right effective measures to eliminate the static electricity of the equipment to protect the printhead and circuit board.

• The Cleaning way has an effecton printhead.

Recommend to wipe the nozzle with a quality soft non-dust cloth or a soft sponge or sponge swab .

• Theworking habits has an effect on

Drying is most easily reason to block up the printhead, if printhead not use for a long time, should found a way to prevent the nozzle from drying out. In addition, be careful do not scratch nozzle while do cleaning.

• Ink viscosity has an effect on printhead.

The ink viscosity is high, If heating circulation is not good, ink adhesion in ink tube, may result in insufficient inkjet volume and color breakage.

SOLUTION : Enhance the indoor temperature to reduce the viscosity of the ink.

The ink viscosity is low ,when sprayed ink on the lamp cloth will easily reflect back to nozzle and accumulate on the nozzle, which cause block up issue .

SOLUTION :Wipe the nozzle with swab cotton dipped in cleaning solution. Change high viscosity ink if want to resolve this problems completely.

Printhead Maintenance Methods:

Doing proper and effective maintenance everyday can greatly reduce the possibility of nozzle block.

1. Installation complete and initially maintenance of printhead.

• Before start printer andwork formally, please be sure to print pictures with C M Y K as many as possible for 1-2 days, and do test-print with C,M,Y,K four colors ensure that all nozzles keep ink-jetting condition.
• Better take outthe sponge and cleaning bracket together from the machine during printing

2. Daily maintenance of printheadbefore shutting down the machine

• Clean theprinthead and make surenozzle in a good condition, turn off device power.
• Clean the moisturizing sponge or non-woven fabric with special cleaning solution andsoak it.
• Move back the carriage to cleaning side and tightly combined nozzle and the moisturizing sponge or non-woven fabric, or cover the nozzle surface with cleaning solution and tightly wrapped with cling film , to reduce the volatilize of cleaning solution.
• Keep device in this status all night till tomorrow.

3. The treatment method of nozzleblocked.

• It is very important to clean it timely when the nozzle has slightly blocked.

Here are some tips: Clean the outside nozzle ink drop with a cotton swab dipped cleaning solution, suck out the residual ink from inner printhead by vacuum cleaner. Can also use Self-cleaning program of printer to clean.

• The treatment method of frequently blocked nozzleduring printing.

Suspending work, keep the equipment power on, move the carriage to the cleaning position,pull off all the float switch datalines connected sub-inktank and printhead board, also unplug the ink supply tube (sub-tank end), then clean using the syringe extract the special cleaning solution to clean the nozzle, after cleaning re-connect with float switch cables and ink supply tube , then continue the work .

• If the nozzle is seriously blocked, may need toclean it deeply manually

1^st, Detach the printhead out from the install frame.

2^nd, To put the printhead into a clean glass container (poured appropriate amount of special cleaning solution) and the head bottom soaked 2-3mm, seal the glass container by cling film and put to anti -ash place it for 1 day or more .

(Pay attention that do not let the signal interface on the top ofprinthead touch the cleaning solution)

3^rd, After socked printhead, do microwave shaking with a speical ultrasonic cleaner, put the printhead into a clean glass container (poured appropriate amount of special cleaning solution) soaked bottom 2-3mm deep, then start the cleaner, not the time should be less than five minutes, to prevent from detroying the inner circuit.

This process shall not handle more than three times continuously.

4^th, Use syringe to draw 40ML special cleaning solution, pull off the ink tubes, insert to ink inlet of printhead, make cleaning solution enter printhead till the nozzle inner ink is flushed out. Observe the status of water line spray out from printhead during the cleaning process, if all waterlines are straight ,it means the cleaning was effective, head can continue to be used ( on condition that both circuit and piezoelectric crystal are intact). If the waterlines are not straight, then try re-do serveral times of process 2^nd and 3^rd.

• Recommed to send printhead back to manufacture to do repairing if it is blocked seriously.

Other precautions for printhead maintenance.

• The socket of the printheadshall not be touched by hand, ink or cleaning solution etc, to avoid The contaminated socket can be cleaned by alcohol.
• The socket of printhead must be aligned and shall not be hard plugged during the installation, once the pinholes broken or not properly inserted, printhead can’t work normally.
• Printhead must be kept in a good heat dissipation environment ,otherwise may causedamage of head circuit.
• Static electricity is seriouslyharmful to printhead circuit, so must eliminate static electricity factors.
• Use purge ink and test-print fuction of printerprogram, ensure that all colors will be inkjeting regularly during printing.
• The surface of head nozzle film is made of polymide film, should be careful when installing and disassembling,cleaning and immersing. If it is injured by hard object, will cause the nozzle beam ray not straight and will affect image quality.