Frequently Asked Questions
The information provided by Arpa Industriale S.p.A. ("Arpa") in this document is solely indicative. Arpa is unable to warrant the accuracy and completeness of this information. No rights can be derived from the information provided; the use of the information is at the other party's risk and responsibility.
This document does not guarantee any properties of Arpa's products.
To counterbalance the effects of possible variations in material sizes, it is almost always necessary to apply a sheet of laminate to the back of composite panels, as similar as possible to the one on the front, (preferably of the same thickness, from the same manufacturer and cut in the same direction). In addition, simultaneous pre-conditioning of the substrate, the laminate and the balancing sheet is essential prior to bonding.
2. What are the most suitable substrates for HPL?
Plywood, particle board and MDF are all particularly suitable because, like the laminates, they are cellulose based and therefore have similar dimensional movement. In some industries and applications they require special substrates such as mineral fibre boards, sheet metal, foam or honeycomb panels etc. These materials all require special bonding and manufacturing techniques. Before proceeding with application, it is always advisable to check with the Arpa technicians.
3. Can the laminate be bent?
When the laminate needs to be bent, the "postforming" grade should be chosen (either HGP or VGP); this retains all the properties of HPL but is also capable of being hot formed into either concave or convex shapes. For detailed information customers can refer to Arpa's technical documentation or contact Customer Service.
4. What alternatives are there for finishing the edges of a worktop?
There are several options:
- using postforming HPL and bending it, as the design requires
- bonding a strip to the edge, of the same HPL as used for the surface
- with PVC, bonding a strip to the edge
- with wood, gluing a strip to the edge of the composite panel
- with Arpa Unicolor HPL, borders are not necessary, as this product has a core of the same colour - as the surfaces (full colour).
5. Can I make internal cuts without risk of the panels splitting or cracking?
Yes. Rounded corners need to be formed (5mm radius) and 90° angles avoided at all costs. Care should be taken, when forming notches and holes, not to induce micro cracks that could degenerate into real splits in the long term. In addition, the composite panel must have been manufactured with rigid or semi-rigid adhesives and, of course, with suitably pre-conditioned materials.
6. Can metallic laminates be worked and bent like the others
Metallic laminates require special attention but they can be worked with the normal equipment used for all laminates. Metallic laminates are also available for postforming. For detailed information on these processes, Customers can refer to Arpa's technical documentation or contact Customer Service.
7. What substrates can be used for metallic laminates?
Compared to other high-pressure laminates, metallic ones require greater care in the choice of substrate and adhesive. To achieve good results, the substrates should be perfectly smooth and the surfaces free from any undulation or blemish. Various adhesives (other than those that are urea based) can be used but the best results are obtained with a very evenly spread PVA type adhesive (which has no tendency to shrink) because this minimises the risk of irregularities extending over the finished surface.
8. In what circumstances should HPL Compact be chosen and how is it handled?
This is a particularly versatile grade of HPL, a strong, durable and homogeneous material, with excellent dimensional stability. It is much thicker than normal laminate and usually has the decor on both sides. Because of these properties it is often used to create partitions and wall coverings in densely trafficked public spaces, lockers or cubicles in damp environments such as swimming pools and gyms or laboratory benches.