The demoulding speed is too fast, that is, don't lift the screen too fast after printing the glue.
There is residual glue at the bottom of the screen, which is not cleaned in time, which is also a factor that is easy to cause wire drawing.
The viscosity of glue is too high, because the glue is closely related to the climate, and the temperature is very high in summer, so the glue is easy to dilute; On the contrary, the temperature is very low in winter, and the glue tends to thicken, so the pressure needed for sizing will be greater. I hope I can help you!
Question 2: How to print the drawing effect? Just make the effect in the designed document.
Question 3: How to draw ink printing? The simplest method is to add ink thinner.
In addition, the printing speed slows down and the printing pressure becomes lighter.
Wire drawing can generally be solved by the above three methods.
Question 4: Printed matter is brushed. How to solve it? Is it screen printing?
There are generally two reasons for drawing silk screen printing ink. One is static electricity, not ink viscosity.
An ion fan can be installed beside the machine, or the ambient humidity can be increased. The other is to adjust the viscosity of ink, generally reducing the viscosity.
Question 5: Why draw cervical mucus? At different times of the cycle, the degree of stretching is different.
(1) The phenomenon that after the active period of the adhesive is exceeded, the adhesive partially solidifies and becomes filaments under tension [1].
(2) When spraying, the coating is not atomized well, so that the coating can not be converted into fine droplets, and it is sprayed in a filiform manner, and the obtained coating can not be leveled, resulting in wire drawing. The reason is that the coating construction viscosity is high and the diluent solubility is poor. Appropriate solvent should be selected and adjusted to the appropriate construction viscosity, so that the coating can be fully atomized and leveled during spraying to avoid this disadvantage.
(3) Wire drawing is a metal processing technology. In metal pressure machining, the metal is forced to pass through the die under the action of external force, and the cross-sectional area of the metal is compressed to obtain the required cross-sectional area shape and size. The technical processing method is called metal wire drawing process, and the tool to change its shape and size is called wire drawing die.
(4) This series of films is a series of functional hard coating products specially designed for printing purposes. Both sides (including coating) can be printed with solvent and UV ink, including varnish, excellent scratch resistance and wear resistance, outstanding embossing and punching performance, excellent aging resistance of common household cleaners and many other substances, and can provide various surface textures except transparency.
Question 6: Can screen printing give the effect of drawing? If the effect is good, the effect is good, and the effect is poor.
Screen printing belongs to stencil printing, which is called four-stroke printing together with lithography, relief printing and gravure printing. Stencil printing includes copying stencil, engraving stencil, stencil printing and screen printing. The principle of stencil printing is that when printing, the ink is transferred to the substrate (paper, ceramics, etc.). ) pass through the perforation of the template with a certain pressure to form an image or text.
Question 7: How to solve the problem of ink drawing in the process of screen printing metal? Common drawing is mainly divided into:
Shallow net position map,
Solid color block scraper position map and printing blank irregular map
three
Kindness
First, the position of shallow wire drawing
1.
Eliminate wire drawing from the source of design and plate making
Fully consider printability in manuscript design and plate making. Be sure to consider the printing direction and try to avoid printing from shallow to deep; Black and magenta versions
The light screen is the easiest to draw, especially the black screen version. Because of the coarse carbon particles in the ink, it is almost impossible to fit a dot when the black screen is very shallow.
Carbon particles, so it is easier to draw. Therefore, a large area of black screen should be designated as a special gray version as far as possible to reduce the printing difficulty and rejection rate.
2.
Use scraper correctly to avoid wire drawing.
( 1)
Selection of scraper.
The surface hardness of chrome-plated cylinder is
HV850
~
1 100
,
The hardness of the scraper should be lower than that of the printing plate.
about
HV600
If the hardness is too low, the ink can't be scraped clean, and if the hardness is too high, it will accelerate the wear of printing plates, produce knife marks and affect the quality of printed matter.
(2)
Smoothness of scraper. When installing the scraper, flatten the blade first, and tighten the screws from the middle to both sides in turn, which cannot be achieved in one step.
It needs to be repeated two or three times to ensure that the blade is evenly stressed.
(3)
Sharpness of scraper.
free
600#
Water sandpaper or 2
#
Metallographic sandpaper grinding scraper,
Or use a special sharpener,
Grind the back of the scraper.
A signed agreement/agreement
25
Even if the knife is new, it should be sharpened.
(4)
Scraper angle.
Compared with normal printing, the scraper angle is smaller,
At the same time, the distance between the contact point between the scraper and the printing plate and the stamping point is shortened.
3.
Reasonable selection of ink to prevent wire drawing
( 1)
When there is a large area of shallow net or horizontal transition on the page,
You should choose good quality ink,
Prevent the ink pigment particles from being too thick to cause wire drawing,
through
The fineness of ordinary ink is
15μm
Too rough ink particles do great damage to the scraper and printing plate.
(2)
When preparing ink,
On that premise that other pattern on the same printing plate are not affect,
Slow-drying solvents should be considered.
Don't add too much vinegar
Auxiliary solvents, such as ethyl acetate, will hinder normal printing due to ink change.
(3)
Ensure the ink viscosity is moderate and stable. The production of wire drawing is directly related to the viscosity of ink. Generally speaking, the higher the viscosity of ink,
The easier it is to generate cutting lines in printing. In addition, due to the different properties of various brands of inks, the amount of solvents added is also different, which can be used as a reference when preparing inks.
The specific data is provided by the ink manufacturer, and the specific operation is carried out in combination with its own printing conditions and prints.
Second, the scene color block cutting position drawing
The line drawing of the cutting position of the solid color block shows that the edge of the solid color block is raised by the scraper, which is generally
Short silk of several millimeters is mainly caused by excessive viscosity of ink and excessive crystallization of pigment particles in ink. The solution is as follows.
1.
Filter the ink and replenish a certain amount of new ink during use.
2.
Reduce the angle of the doctor blade and shorten the distance between the contact point between the doctor blade and the printing plate and the imprint point.
Third, irregular drawing in printing blank.
Random drawing in the blank of printing shows irregular ink knives, sometimes short, sometimes short, usually thick. Causes and solutions
As follows.
1.
There are foreign objects on the blade or under the scraper.
Before and after the printing process,
Move the scraper up and down,
Put away the adhered foreign matter or remove it directly on the blade of the scraper with a bamboo stick.
(Will
Must be completed by skilled operators to avoid unnecessary losses caused by improper operation), and stop the machine to clean the scraper thoroughly if necessary.
2.
Insufficient ink circulation
Part of the ink in the dead corner of the ink tank, due to poor circulation, causes resin precipitation, forms crystals and lumps of different sizes, or is excessive.
Dry separation leads to the formation of ink skin on the surface (ink skin is easy to occur in summer, and ink crystals are often caked in spring and autumn due to temperature).
With the circulation of ink, some ink crystals or ink skins are brought to the blade by the rotating plate cylinder and broken by the scraper to form graffiti.
Silk. Therefore, we must improve the fluidity and filterability of ink.
( 1)
Cycle improvement
First, tilt the ink tank left and right to ensure that the ink can be injected from a slightly higher end and flowed out from the lower end to form a good circulation; square
Method two, put the ink tank flat, but the ink must be injected from both ends at the same time and refluxed from the middle, which can also form a good circulation and cannot be injected from one side.
Enter the ink.
......& gt& gt
Question 8: What is ink painting? Especially silk-screen paintings! Please express it in common language! Please don't copy the silk-screen ink painting on the Internet. When printing, the ink is too thick when lifting the screen, and then the ink between the screen and the substrate is pulled out.
Question 9: How does 9:uv printing wire drawing silver make the ink particularly strong? Drawing silver is also a kind of metal plate, and uv printing drawing silver needs spraying layer to increase the adhesion of ink. Metal plate, glass, ceramic tile, etc. Usually need to be sprayed. Let me remind you that different materials choose different coatings. Please pay attention to this. It is recommended to test before printing to avoid loss.
The biggest feature of uv printer is that it can print without plate making. The print size depends on the print size of the printer. Of course, it can also be printed in blocks. Printing materials are as small as packaging boxes, cosmetic boxes, USB flash drives, etc. , as big as glass, tiles, boards, metal plates, acrylic, etc. As long as it is a flat material, it can be printed. Because of its wide printing range, it is also known as a universal printer, which can not only print 3d effects, but also print relief effects.
The first thing to consider when choosing a uv printer is the stability of the printer, the choice of nozzles, the later maintenance cost (the price of replacing nozzles), after-sales service and other factors. It is recommended to choose Toshiba uv printer.
Take the nozzle as an example, Ricoh g5 nozzle costs more than 20,000 yuan, Toshiba CE4 nozzle costs about 6,000 yuan, and Toshiba's service life is 24-36 months. Toshiba's printing speed is twice that of Epson, and its accuracy is higher than Ricoh's. Toshiba's nozzle is guaranteed for two years, which determines whether the cost of the printer will increase in the future use.
Question 10: I recently entered a plastic flexible packaging color printing factory. I heard that the printer often said "color difference" and "wire drawing" but I didn't understand them, so I asked my colleagues to explain! Color difference refers to color deviation; Wire drawing means that there is garbage on the printing plate roller, which leads to poor ink transfer during printing.