Terminal block labelling - Kablo Etiketi

Material properties
Comparative properties of polycarbonate and polyamide label plates
For your label plates Murrplastik Systemtechnik uses high-quality polycarbonate meeting the requirements laid
down by UL94 for the top fire classification V0. This offers clear advantages over polyamide as used by our
competitors.
Polycarbonate (PC) is used in applications requiring a high-quality surface finish in respect of scratch resistance
and gloss level. As such, PC is widespread in the automotive sector, where examples of its use include headlight
lenses and PC/ABS blends in the interior. By contrast, polyamide (PA) is rarely found as a blend in interior fittings.
Polyamides are, however, prevalent under the bonnet, for example, where less significance is attached to the
appearance.
For use as a label plate polyamide has another unfavourable property: ambient water absorption of approx. two
weight percent. This can cause dimensional variations (small dimensions at low temperatures and low air humidity,
large dimensions at high temperatures and high air humidity). While this may not affect the dimensions of the
label plates too severely, it does unduly impact on the properties of the material. Indeed, if water absorption is
low the material is very brittle and tends to break (e.g. when latching onto a terminal block). Conversely, if water
absorption is high then it is very soft and it may be difficult to separate plates from each other (tear response).
In terms of its inscription properties polycarbonate is streets ahead of polyamide. Since PC is more prone to
chemical reaction it lends itself well to ink and also laser inscription. Whereas PA scarcely reacts to the energy
application of laser light the colour change achieved with PC is outstanding.
The chemical reactivity of polycarbonate during inscription makes it an excellent abrasion-resistant surface for
inks. If the resistance to abrasion and water is good in both materials then the inscription on polyamide wears
off significantly if comes into contact with oil, petrol or spirit. Polycarbonate, however, is also resistant to these
substances.
Material description
Material Description
Polycarbonate (PC): Excellent surface gloss and transparency (natural), high mechanical
strength and dimensional stability under heat, outstanding electrical and
dielectric properties, superb dimensional accuracy and low water
absorption. Impact resistance up to approx. 150 °C and, as a general
rule, PC is self-extinguishing without the addition of fire-retardants.
Polyamide (PA): Broad range of properties covered by different types (PA 6 and PA6.6
are frequently used). Generally good electrical and mechanical properties
with resistance to impact and abrasion being particularly strong.
When dry, PA is sensitive to impact. Water absorption renders PA flexible.
Polyvinyl chloride (PVC): Soft PVC is made from polyvinyl chloride, softeners and process
materials, e.g. stabilisers and lubricants. PVC is resistant to corrosive
saline solutions and most acids.
Thermoplastic polyurethane (TPU) : Outstanding features of this material include its high flexibility even
at low temperatures, high continuous operating temperature, high
resistance to tear propagation and very good restoring forces, high
resistance to grease, oil, solvents, high-energy radiation and ultraviolet
light.
184 Murrplastik Systemtechnik GmbH Postfach 1143 D-71567 Oppenweiler A +49 (0 ) 71 91/4 82-0 E +49 (0 ) 71 91/4 82-2 80 www.murrplastik.de info@murrplastik.de