Köraform A 42 - Scabro

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PRODUCT INFORMATION Version 04/2008
Köraform A 42
Transparent addition curing two component silicone moulding compound for the reproduction
of master pattern (rapid-prototyping process)
• Good flow characteristics and high
transparency
• Excellent recovery
• Very high resistance to cast resins
• Rapid prototyping
• Transparent moulds
• Improved resistance to curing problems
(inhibiting)
• Adapted for - applications
Option for use with 3 different B-components for individual adjustment of Köraform A 42 to specific
requirements.
- Pot-life and curing time
- Dry or „moist“, self separating surface
- Mechanics
Köraform A 42 + Köraform A 42 B
- standard type
- silicone rubber with dry surface (casting of transparent parts)
Köraform A 42 + Köraform A 42 BW
- highly elastic
- extreme tear resistance
- excellent release properties
- improved resistance to cast resins
Köraform A 41/42 BL (pot-life extending agent)
Pot-life and curing time may be adjusted to the specific working conditions (mixing by hand or by mixing device) as well as to
the mould dimensions by adding Köraform A 41/42 BL. Mixing ratio A : B component of 10 : 1 remains unchanged. The mixing
ratio of the B components A 42 B and A 42 BW with A 41/42 BL changes the pot-life. The different pot-lives are shown in the
following list together with the respective waiting times for earliest removal from the mould.
Köraform A 42 B or A 42 BW : Köraform A 41/42 BL Pot-life (min) Earliest demould (h)
10 : 0
7 : 3
3 : 7
0 : 10
90
135
270
300
12
17
24
30

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KÖRAFORM A 42 Version 04/2008
TECHNICAL DATA
Base
Köraform A 42
A component
Köraform A 42 B
B component
Köraform A 42 BW
B component
Colour transparent transparent transparent
Viscosity 62 000 650 6 000 mPas 1)
Density 1,09 0,98 0,98 g/cm³ DIN 53 479 1)
Mixture
Köraform A 42 + Köraform A 42 +
A 42 B
A 42 BW
Mixing ratio 10 : 1 10 : 1 by weight
Viscosity 35 000 36 000 mPas
Pot-life 90 90 min
Earliest demould 12 12 h
Cured rubber
Hardness Shore A 42 40 DIN 53 505 2)
Tensile strength 6 5,6 N/mm² DIN 53 504 S 3 A 2)
Elongation at break 300 320 % DIN 53 504 S 3 A 2)
Tear resistance 25 30 N/mm ASTM D 624 Form B 2)
Linear shrinkage 0,1 0,1 % After 7 days 1)
Der Platinkatalysator befindet sich in der A-Komponente
1)
= Measured at Standard Climate according to Din 50 014-23/50-2
2)
= Vulcanized material, measured after 14 days of storage at Standard Climate, DIN 50 014-23/50-2
1)
1)
1)
1)
Distributor for The Benelux:
Scabro
Vliegveld Valkenburg
Wassenaarseweg 75-3265
NL - 2223 LA Katwijk
Tel: +31 (0) 71 4017246
Fax: +31 (0) 84 7402572
Email: info@scabro.com
Internet: www.scabro.com

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KÖRAFORM A 42 Version 04/2008
PROCESSING
Preparation
Component A is mixed with component B in the ratio of 10 : 1
by weight. Stirr the mixture thoroughly using a spatula or a
mixing device until the material has become homogeneous.
The pot-life during which Köraform A 42 must be processed
(casted or applied with a brush) starts with the mixing procedure.
Earliest removal from the mould can be carried out
after 13 hours at a temperature of 23°C minimum. A longer
pot-life can be achieved by using the pot-life extending agent
Köraform A 41/42 BL.
Prior to casting, the mixed silicone has to be degassed under
vaccum pressure in order to achieve a completely bubblefree
vulcanized material.
Viscosity can be increased up to creep stability by adding up
to 0,2 % by weight of Köraform TM to the A component.
Curing problems (inhibiting)
Certain substances can slow down or even completely halt
the curing of addition cross-linking silicones. Typical symptoms
are tacky surfaces of the silicone towards the contact
surfaces.
The following substances have to be particularly inspected
with utmost care:
- nitrogen-containing substances (amines, polyurethane,
epoxy resins, ...)
- sulphurous substances (polysulfides, polysulphones,
natural and artificial rubber (EPDM))
- organometallic compounds (organo-tin-compounds,
vulcanized materials and hardeners of condensation
cross-linking silicones)
CLEANING
Use Körasolv GL in order to remove fresh material. It is advisable
to let residues in the mixing or casting container
completely cure and to peel them off then.
SPECIAL NOTES
Storage
Köraform A 42 A and B components will retain their optimum
processing characteristics for at least 12 months when stored
at 5 – 30°C in the tightly closed original container.
SAFETY
Please notice the indications on our EC-safety-data-sheets
and the safety-indications on the labels of each product for
the treatment of our products.
Especially the directions of the Dangerous Substance Regulation
and the Accident Prevention Regulation of the Employers
Liability Insurance have to be respected.
Keep the EC-safety-data-sheet of the product you treat ready
to hand. It gives you valuable indications for the safe usage,
disposal and in case of accidents.
PACKAGING UNITS
When casting to unknown substrates, a compatibility test is
indispensible.
Distributor for The Benelux:
Scabro
Vliegveld Valkenburg
Wassenaarseweg 75-3265
NL - 2223 LA Katwijk
Tel: +31 (0) 71 4017246
Fax: +31 (0) 84 7402572
Email: info@scabro.com
Internet: www.scabro.com