The assembly process involves a dispenser or
a screen printer, a spacer spray machine, the assembly machine and a hot
press machine as well as final cure oven.
In order to prepare the assembly of the panel, on one glass plate a
seal has to be dispensed or printed by screen printing.
Some wholes are left open in the sealing in order to allow later
filling of the display with liquid crystal liquid. A pre-cure step is required, using a
On the second glass plate the spacers are sprayed using a
spacer spray machine.
In the assembly machine, the two glass plates
have to be put together. On the lower glass plates dots of UV hardening
polymer are dispensed. The upper glass plate has to be turned over,
orientated versus the lower glass plate, using marks on both glass
plates and a proper pattern recognition system. Then both glass plates
are pressed together and UV lamps harden the polymer spots in order to
fix the position of the two glass plates for some time.
After the mounting of the two glass plates
and the formation of a panel in the assembly machine, the sealing has
to be hardened. This happens in a so called hot press machine. The
panels are in a first step carefully evacuated. During evacuation the
normal air pressure from outside will press the two glass plates
already together and air is taken out of the cells. This is helpful in
order to avoid a damage of the seal during hot press process. The
compression stays for a few minutes after purge. Then the main hot
press follows in two steps. A hot press unit always consists therefore
of two presses. The first step works with little bit lower temperature
and pressure than the second step. The panels are transported to the
presses by a carbon fibre belt who stays in the press during the
process and ensures a good pressure uniformity on the panels.
Depending on the required throughput a hot press consists of
several hot press units. The market share is
estimated to be around 95% for treatment of larger displays (>G3,5).
We can also recommend proper sealant material to the customers.
During the hot press process the seal gets 90% polymerised. The final
polymerisation takes little bit longer is done is a
Manuel versions for research and development are available for assembly
machines as well as for hot press machines.
Manuel versions for research and development (Joyo Engineeing)