Screen printing machine operation without ink, the understanding of the nature of the ink in a correct way will help a printing machine used for a long time!
Screen printing machine is printing machines, is one of the important raw material for the production of printing ink, its performance directly affects the products of printing quality and production efficiency.
So, correctly understand and recognize the nature of the ink, in the process of actual production operation according to the printing conditions and characteristic are appropriate for certain properties of ink to adjust and improve, to improve the production efficiency and product quality will have better effect.
thixotropy
Thixotropy ink refers to ink is getting thinner after once churn, friction, increase its liquidity, and let stand for a period of time, and will restore to its original state of thicker ink.
In printing ink transfer process, after the ink fountain and the rotation of the rubber roller friction, make its temperature, and also increase liquidity, ductility, until after the transfer to transfer ink to print, disappear due to external force, its liquidity, the ductility decreases, then by dilute thicken, so as to ensure the clarity of the printing ink.
If ink thixotropy is too big, easy to cause plugging ink, paste version and other ills, as the printing process, more and more thin, ink print ink printing more and more weak, caused by not clear, the problem should be paid attention to when printing.
Ink thixotropy have greater than little adverse impact on printing, printing ink with proper thixotropy.
viscosity
Viscosity fluid material refers to stop the flow of a character, is a fluid intermolecular interactions, resulting in a measure of the relative movement ability of the block, the fluid flow resistance.
If ink viscosity is too big, the printing ink transfer in the process of difficult evenly, easy to cause image sticking dirty, ink, the ink transfer, hair pulled off paper paper powder, make the layout of the paste or hair flower;If ink viscosity is too small, are prone to slip, causing printing bar mark, and mark hair light, printing ink emulsification, dirty etc. Bad phenomenon.
liquidity
Liquidity refers to the ink will flow like a liquid under their own gravity, the ink viscosity, yield value and thixotropy of the decision, but also has close relationship with temperature.
Ink liquidity affect the ink in ink tank, ink fountain, ink roll and passed between the substrates, which affects the printing effect.
Big ink viscosity, liquidity is poor;The low viscosity of the ink, liquidity is good.
dry
Ink should have good drying performance, ink drying too fast or too slow will affect printing process and the control of printing quality.
If the ink dry slowly, printed in the process of accumulation, and easy to cause the back stick dirty, severe adhesion phenomenon would appear, imprinting lacklustre even pulverization.
If ink drying too quickly, in the process of printing ink liquidity is difficult to control, which may lead to a difficult heap ink, ink roller transfer ink, ink inconsistent, the paper off powder dropping, ink film crystallization, etc, will also destroy the ink roller surface performance.
fineness
Ink fineness is refers to the ink pigment (including filling material) in pigment particles and particle size distribution in the link of material evenness.
Fineness good ink prone to preach in the process of printing ink and ink uneven, JiMo paste version, wear plate, color effect is not good and so on quality issues.
Relatively good ink fineness of its concentration is bigger also, the printing is clear.
If the ink fineness, print dot layout is easy to be afraid, paste, plate printing resistance rate is low.
Tinting strength
Ink tinting strength depends on the size of the ink color depth.
When ink tinting strength is big, the printing color is dark;On the other hand, the printing color slants shallow.
Tinting strength of large amount of ink in printing ink quantity is relatively small, ink quality is better also.Conversely, tinting strength small amount of ink used in printing inks for the relatively more, inky is relatively light.
Yield value
Yield value is the minimum shear stress required to instigate liquid to flow.
Yield value too much ink, poor flow property;Yield value is too small of ink, printing dot easy dizzy, not clear.
Light fastness
Ink under the action of light, the color changes in relative performance called ink light resistance.
In fact, there is no absolute don't change color ink, in under the action of light, any color more or less ink will produce change.
Light fastness good ink, bright color printed products, the columns of the outlets of fat, rich stereo feeling, and can be long-term preservation.
And poor light fastness of ink, printed ink prone to fade and become angry phenomenon.
Acid and alkali resistance and alcohol resistance
Acid-proof, alkali resistance and alcohol resistance strong inks, ink printed products bright, structured layout, clear network.
Printing ink with acid, alkali resistance and alcohol resistance is the basic requirement of packaging products, such as print for packaging of soap, soda, or food, used in printing ink must have good acid and alkali.
In addition, glazing oil containing alcohol solvent, so need to polish products used with ink, alcohol resistance must be considered in order to avoid adverse phenomenon.
Paper and ink performance varied, they are all in a certain extent affect the printing quality of the product.Learning and understanding the nature of the paper and ink, helps to avoid the blindness of printing process operation, prevent the occurrence of fault in the process of printing, the printing efficiency and quality are improved synchronization.Information from: screen printing machine