The
heat transfer printing film can be printed on the printing machine after the
materials are fully prepared. Generally, the release layer, printing layer and
adhesive are coated and printed on a unified gravure printing machine.
Unwinding: Mount the base film in the center of the unwinding roller, pass it
between the impression roller and the plate cylinder, and then pass through the
constant tension traction roller and enter the winding roller.
Adjust
the paper feeding force according to the diameter of the roll, and set
different drying temperatures according to the different materials to be
coated. Distribute the release agent first, pour it into the coating tank and
stir evenly. Turn on the gravure printing machine for coating. The coated
substrate film is dried on the drying equipment. The drying temperature can be
based on the temperature required by the release agent or Set according to the
data provided by the manufacturer. The release agent has a very short curing
time on the surface of the base film, but to achieve a better transfer effect,
the solvent must be allowed to evaporate completely before preparing to apply
the ink. Therefore, the drying temperature can be appropriately higher, or in
2-4 colors. The group is boring. The coating thickness of the release agent
should be controlled at about 5 μm. It should not be too thick or too thin. If
it is too thick, the release layer will easily fall off the base film. If it is
too thin, the printing layer will not be completely transferred during thermal
transfer.
The
printing layer of thermal transfer film is generally gravure printed. Pass the
base film roll coated with release agent through the middle of the impression
roller and the printing plate roller. The printing plate roller rotates in the
ink tank to print out the graphics and text, and then passes the drying
equipment to the printed The ink layer is dried to accelerate the drying speed.
The drying temperature of thermal transfer ink is selected according to its
solvent. If the solvent is fast-drying toluene, the drying temperature can be
appropriately lowered; if it is slow-drying xylene, the drying temperature
should be increased. At the same time, please note that the printing color
sequence of the thermal transfer film is opposite to the general printing color
sequence, that is, the ink with high transparency is printed first, then the
ink with low transparency is printed, and finally a layer of white ink is
printed as needed. The function of opaque white ink is to cover the color of
the substrate itself, so that the level and color of the graphics and text
transferred to the colored object are not affected.
To
avoid damaging the graphics and text on the printed layer, the adhesive layer
should be applied when the printed layer is completely dry. The adhesive layer
can be directly coated on the last color group of the gravure printing machine.
The coated substrate film is then dried. The drying temperature is determined
according to different substrate films. It is controlled by the rewinding air
shaft and the paper release The axes are the same, and the winding force is
controlled by the winding motor to control the traction force of the traction
roller, which is generally the same as the tension at the paper release point,
so that the machine can operate normally. When one reel is finished, it can be
cut and then rolled onto another reel. Thermal transfer film rolls will be cut
into products of different widths as required. In order to save costs, thermal
transfer graphics and text are usually evenly distributed on a printing plate
according to size, and then cut when used. At the same time, it is important
that the cutting machine must have automatic correction equipment, otherwise it
will affect the overall effect of the graphics and text.
During
the printing process, release agent, ink and adhesive must be replenished at
any time, and the roll film must be placed on the paper feeding mechanism in
time to ensure continuous and normal printing. It is also necessary to
regularly check the coating status of each material of the thermal transfer
printing film, whether there are white spots, dirt, streaks and other defects
on the printed sheet, and to promptly remove rough printing defects.
Name: Edison
Mobile:+86-17669797337
Tel:+86-17669797337
Whatsapp:8617669797337
Email:sales@ulikefilm.com
Add:Dazhuge Industry Park,Jiaozhou City,Qingdao,China