Ensure the normal order of the printing screen has a certain tension, but the stability of the printing for depends on the tension lasting constant, practice has proved that screen keeping the tension at 14 ~ 18 n/cm is most suitable for screen printing cylinder products.Cylinder products especially the geometric center of rotation of hollow plastic products and fixture of the centerline are often not overlap, lead to the ups and downs of the printing process, excessive tension is not easy to adjust the limits.For multi-color printing, we also don't sum print that has the high tension, and make the guarantee four equal network version of tension.
Silk screen printing process
1) scraper:
Scraper in screen printing transfer printing pressure and printing ink, its hardness and shape and printing the perfect Angle is one of the basic parameters influence the function.
First of all, is the most commonly used cross section shape of the scraper pointed triangles and rectangles, rectangular used for print, pointed triangles used as surface screen printing, this is because the surface of a line of printing, pointed triangles are more likely to get smaller printing pressure ideal ink.Previously, ups and downs in the process of rotating cylinder products also provides for the application of pointed triangles of the stencil good comments.
Second, the stencil is considered one of the parameters of the hardness of the same circumstances, the condition of all printing soft plastic blowing pressure on screen is smaller than a hard plastic blowing pressure.The greater the pressure, printing ink will clear some more.For cylinder products, and products to choose rubber hardness is clearly inappropriate, the pressure of the cylinder product need more small, so the hardness of the best control under 80 degrees.
2) the net distance
The net in the silk screen printing is silk screen printing process in unique variables, it directly affect the ink transfer effect.Too big and too small distance will be a negative influence on the silk screen printing.Cylindrical products after screen press and the bus line contact condition of determines the distance than a face screen printing.There is no fixed number, can the key is to test out the most suitable results.
3) silk screen printing machine
It is obvious that the cylinder products of printing must be chosen which has the function of surface screen printing press.Curved surface screen printing machine and flat screen printing machine is the difference between the network version of the former in the printing process for reciprocating motion plane, and products in the web version of the rack drive low rotary motion.
Most curved surface screen printing press will be fixed in the hollow plastic end on the rotation of the drive gear fixture, the parameters of the gear is very important, otherwise the printing can be a problem: we must make gear indexing the diameter of the circle and the diameter of the hollow plastic bottles are equal, so, in the printing process on the first edition of graphic will accurately transferred to the surface of plastic bottles.