Instructions for application
The following instructions are an introduction to the proper processing and application of SurACer® 4450.
1. General
Experience to date has been that now and then mistakes are made when SurACer® 4450 is being used. By following the notes below, mistakes can be avoided which might lead to problems with quality or adverse effects on products, with possible consequences under guarantee.
The criteria to be applied when working with SurACer® 4450 fall under the following headings:
- Storage
- Mixing ratio
- Mixing of components 1 and 2
- Open time
- Curing
2. Storage
The mixture (after components 1 and 2 have bonded) must be stored at room temperature (20° C) in the dark.
Before component 1 (from the yellow plastic bottle) is mixed with component 2 (from the blue plastic bottle), the
temperature of both should be raised to between 20° and 40° C.
At a maximum temperature of 20° C, with light excluded, each component of SurACer® 4450 can be safely
stored for at least 6 months.
The viscosity of the components may alter during storage and transport of SurACer® 4450 at low temperatures (below 20° C). Component 1 may crystallise out without affecting the quality. For this reason, both components before use require gentle heating up to 40° C (on a heating plate or radiator or in a bain-marie) to homogenise them. Only then should they be mixed together.
3. Mixing ratio
To obtain the optimum SurACer® 4450 properties, both components must be weighed in the right proportions,
Component 1: 1.0 g / Component 2: 2.0 g
and then thoroughly mixed.
The more accurate the weighing and the more homogeneous the mixing, the better the quality of the doming surface and the
general properties of the material. Accurate weighing of the components (with a tolerance of +/- 0.1 g) is the safest way
to ensure the right mixing ratio. The weighing should preferably take place in the special weighing and mixing container
(Item no. 5388, 5389, 5390, 5395).
The components of a single kilo of mixture have been prepared in advance as component 1 (in the yellow bottle) and component 2 (in the blue bottle),
so that by simply emptying the entire contents of the yellow bottle into the blue bottle the correct mixing ratio is
achieved. It is absolutely necessary to ensure, by flushing the yellow bottle with some of the mixture several times,
that the contents of the yellow bottle have been used in their entirety.
The 5-kilo and 15-kilo sets for bonding are in a white container (component 1) and a blue container (component 2). For
these mixture weights, it is absolutely necessary that the weighing and mixing of the components take place in the
appropriate special weighing and mixing container.
Keeping the mixing ratio accurate is crucial to the achievement of the given product specifications for the hardened
doming material. There will be surface defects and poor quality, ranging from stickiness to patchy hardening, if the
ratio is not exactly maintained.
4. Mixing of components 1 and 2
The mixing of component 1 and 2 has been completed successfully when homogeneous clear mass has been formed from the two.
Any air bubbles imported during the mixing process will escape when the mixture has stood for some time: how long depends
on the quantity of the components blended and might be up to 24 hours. In the meanwhile, the mixture should be kept in the dark.
The time necessary for all the visible air bubbles to escape can be shortened by brief heating of the mixture, to no more than 40° C.
Warning
SurACer® 4450 must never be heated or degassed on a direct flame.
Suitable stirring implements (such as a glass rod, a plastic rod, an anchor-shaped stirrer or a propeller-type stirrer)
and suitable mixing container (see above) should be used for the mixing process. The propeller-type stirrer should be
the one used when weighing and mixing containers with a capacity of 500 or 1,000 ml are
being used, or if component 2 is being stirred in the blue bottle. The anchor-shaped stirrer is appropriate for the 1,000 ml container and should be used in particular for the 5,000 ml container. Both these stirrers can be operated as accessories to a suitable battery-driven screwdriver.
Warning
If the two components are not adequately blended and/or air has clearly been drawn into the mixture as air bubbles,
the end product will show a loss of quality. This is recognisable as pock marks, circles, rods, swirls or the like which
are still visible after the curing process.
SurA Chemicals GmbH wishes to draw attention to these problems attendant on careless processing. The company's quality
management system has been applied to all possible problems and it is clear that inadequate blending and/or trapped air
are the most frequent sources of any difficulty.
5. Pot life
Pot life is defined under the DIN 55945 standard as the maximum period for which a coating material supplied as
separate components will be usable once the components have been combined.
In the case of SurACer® 4450, when components 1 and 2 of have been blended in the prescribed proportions, the pot life
will be 5 days under refrigerated storage. This signifies that the blend will remain workable for 5 days after it has been
made up out of components 1 and 2 as long as the storage conditions are observed.
Even after the end of the pot life, the SurACer® 4450 blend can be used to produce domed surfaces if it is still capable of being dispensed and cured. In this case, experimental runs should be first carried out. The use of SurACer® 4450 after its por life has expired is not covered by guarantee.
6. Curing
SurACer® 4450 domes are hardened in SurALux light curing boxes, series 8204-E/8201-E/8207, specially developed for the purpose. The hardening takes place within between 5 and 10 minutes under illumination with UVA light. This period will depend on the surface area and height of the dome and must be determined experimentally before proceeding to mass production. Curing parameters are listed in the product information sheets supplied with the SurALux light curing boxes.
Warning
For the achievement of the properties specified by the manufacturer, it is absolutely necessary to use the technology
described, which has been adapted to the material involved.
A fingernail test will reveal whether the hardening process is complete: no depression possible. If there is still
liquid present in the body of the dome, the SurACer® 4450 is not fully cured.
It must be subjected to a further curing period. This period should be extended in gradual stages. The curing test
should be carried out after each.
SurA Chemicals GmbH will gladly help in the resolution of any problems; please do not hesitate to get in touch if necessary.
Any advice given orally or in writing will be to the best of our knowledge and is to be taken as non-binding commentary
(also as regards any copyright invested in third parties). The advice does not release the user of SurACer® 4450 products
from the obligation to test in respect of fitness for intended purpose. This manufacturer's liability extends solely to
the value of the products supplied by SurA Chemicals GmbH and put to use by the customer. It goes without saying that
SurA Chemicals GmbH guarantees its products to be of perfect quality as stated in its general terms and conditions of
sale and supply.