U1404 is an extremely elastic polyurethane resin with excellent mechanical attributes that can be used to reproduce soft elastic moulded pieces (e.g. rubber handles) as well as to make moulds of very intricate master forms. The U1404 resin can be mixed using two different hardeners. Variable elastomers with different working life values, curing times, Shore Hardness and mechanical attributes can be produced by adjusting and changing the mixing ratios of the resin and the hardener(s). The individual mixing ratios can be found in the table below.
Regardless of the mixing ratio, poured block moulds made out of U1404 can, as a consequence of their transparency, be carefully cut into without damaging the master form which is not hidden by opacity. In the case of subsequent reproductions, the fact that the mould is transparent allows you to monitor the pouring process by looking through the mould whereby you will be able to better avoid developing bubbles.
In contrast to other polyurethanes, U1404 is less sensitive to moisture and should be worked with at room temperatures of at least 20 °C. If the material is to be coloured, the dye should be added to the less moisture sensitive hardener component before it is mixed with the resin component. As with silicone, care must be taken, when stirring and mixing, that as few bubbles as possible are created so as to assure an accurate mould.
We recommend that the casting moulds, which will have been already treated with a release agent, be tempered to a temperature of 20 °C to 25 °C before pouring the U1404. This PUR resin should not be poured into moulds made from condensation cured silicone.
When using U1404 as a mould material, a release agent must, without exception, be used. In addition, care should be taken that the heat from the typical PUR reaction and the measure of isocyanate it contains does not damage the master form. The cured elastomer does not attain its final mechanical properties until after 4 days time at room temperature. Before that much time has elapsed, moulds made from U1404 should not be used at all or even treated with a release agent. In comparison with similarly priced silicone, moulds made with the U1404 and used for serial production have a decidedly longer service life when an aggressive medium is used in the reproduction process (approximately 80 to 100 moulded pieces instead of the 20 to 25 in the case of the silicone mould).
Resin U1404 with the hardeners U1404 und U1419 L
Resin/Hardener
|
Mixing Ratio (parts per weight) |
Resin U1404 |
80 |
100 |
100 |
100 |
100 |
Hardener U1404 |
100 |
54 |
32 |
10 |
0 |
Hardener U1419 L |
0 |
6 |
8 |
10 |
11 |
Treatment |
|
|
|
|
|
Working Life (at room temp.) |
25 min |
60 min |
90 min |
100 min |
100 min |
Curing Time (at room temp.) |
3-5 days |
5-7 days |
5-7 days |
5-7 days |
5-7 days |
Elastomer Attributes |
|
|
|
|
|
Shore Hardness |
40 Sh-A |
47 Sh-A |
60 Sh-A |
74 Sh-A |
80 Sh-A |
Elongation at Tear |
> 600 % |
1000 % |
1000% |
1000% |
800% |
Tensile Strength |
4 N/mm² |
3 N/mm² |
5 N/mm² |
6 N/mm² |
16 N/mm² |
Tear Propagation Strength |
7 N/mm |
12 N/mm |
16 N/mm |
25 N/mm |
40 N/mm |