INK COOLING SYSTEM **** - Duo-Technik GmbH

INK COOLING SYSTEM ****
Information under
www.duo-technik.de
// COOL INKS
LOOK AFTER
THEMSELVES
// Keep your
inks cool
with the new
Ink Cooling System
from DUO-TECHNIK
// and achieve 4 h
more of the same
viscosity and pH
DUO-TECHNIK GmbH
Phone: +49(0)6641/9695-0
Fax: +49(0)6641/9695-40
E-Mail: info@duo-technik.de

COLOR MANAGEMENT
// Which factors need to
be monitored?
// Viscosity
// PH
// Temperature
With the right viscosity the converting of the inks are improved.
We suggest: for inks: 22-23 sec. Ford cup 4;
for water based varnishes: 20-21 sec. Ford cup 4.
The adhesion of the ink onto the sheet will be improved with the correct
pH-value. In addition the drying results will be improved, too. Basically, the
pH-value should decline from printing unit 1 to the last printing unit. The
pH-value of the first printing unit should be 9-9,5 and should be dropped by
0,2 per each further printing unit. However, it should never be lower than 8.
The ink temperature is influenced by the ambient temperature and the
friction of the inks in the ink circulation of the printing machine. With a fix
temperature the change of viscosity and pH can be controlled and kept on
a stable value. The temperature should be set between 20 and 22 °C (see
chart 1).

INK COOLING SYSTEM ****
The systems temperature control, viscosity control and pH control are modular
concepts. This means that you can decide which system is the right one
for your needs. The following examples make clear when and which combination
is reasonable for you.
Initial position 1: For each job change a new ink with adapted viscosity and
pH is brought to the printing machine. Here, a ink cooling system is sufficient
to hold the viscosity and the pH steady until the end of the printing job.
Initial position 2: You produce mainly with the base colours without changing
these at a new job. Here, we recommend installing all systems.
With consideration of the results of the test series for ink cooling it has to
be the goal to reach the aim temperature as fast as possible and keeps then
the temperature stable for the rest of the time. With the Duo-Technik ink
cooling it is possible to bridge a temperature gap of 10 °C in only 3 minutes.
Furthermore as a result of our own ink circulation we are reducing the micro
foam building. The following technical facts are characterizing the system:
• The ink cooling is working with a central cold water unit (3-5 °C)
• The electrical connection is only 1,5 KW for each printing unit
• The cold water is pumped through a double-walled heat exchanger
until the goal temperature is reached
• With a separate ink circulation continuously ink is brought through
the heat exchanger
• The total system is connected with the cleaning system of the printing
machine that no further actions for cleaning has to be taken place
// Which system is the right
one for me?
// THE DUO-TECHNIK
INK COOLING

VISCOSITY CONTROLS
IS THE 2ND STEP? Viscosity is a proportion to measure the capability of the flow of a fluid. The
higher the viscosity is the less the capability of the flow is. There is no defined
dimension unit for the viscosity. Several dimensions are common: Centi Poise
-> 50 [mPa*s]; Poise -> 0,5 [P]; DIN-Cup 4 -> 16 [s]; Pascalsecond -> 0,05
[Pa*s]; Engler -> 6,62; Ford-Cup 4 -> 22 [s]. Means first of all the right system
needs to be defined for each customer.
DUO-TECHNIK GmbH
Phone: +49(0)6641/9695-0
Fax: +49(0)6641/9695-40
E-Mail: info@duo-technik.de
Furthermore the viscosity depends on the temperature of the fluid (see chart
2), means the viscosity is automatically decreasing with a higher temperature
without any changes of the ink. In consequence of this we suggest to start
with the temperature to have a base for the viscosity comparison.
100
ŋ/mPa s
10
1
water
ethanol
mercury
olive oil
acetone
-100 -50 0 50 100 150
T/°C