For more than 80 years now, nora at its Weinheim location has been producing materials for both shoe components and other industrial applications. The complexity of the materials EVA and rubber, and the specific requirements that our employees’ know-how must fulfil, provide the basis for high-grade, innovative materials of the highest quality.
More than 80 years of know-how, experience in the development and production of innovative materials …
Together with professionals
In collaboration with experienced technicians and craftsmen in the sector, we work on new developments in materials. This has given rise, for example, to the innovative EVA material Lunatec motion, which absorbs shearing forces.
Innovative EVA materials
One of the milestones in 2004 was the first vulcanised composite EVA Lunatec combi, which simplify the sandwich technique. An extensive range of multi-ply composite materials has been growing since then. The benefits are obvious: the manufacturing process bonds the customary material combinations, which can then be used for a great many applications.
Our videos present more about our innovative products and know-how about working with them.
Own development department
Since the very outset, it has always been our goal above all to develop innovative materials that simplify everyday work for the craftsman and offer the industry custom solutions. Materials that promise stability and safety to both technicians and patients alike. To create products that in turn give rise to new special properties and so innovative solutions. That is why we have a competent development department at our production site in Weinheim.
The challenge posed by this production process is the combination of materials with differing densities and hardnesses. Taking control of the behaviour that differing qualities demonstrate in this sensitive production process means years of experience and know-how.
Processing tips and know-how for optimal results
The best material quality is worth nothing when the material itself is not processed to optimal effect. nora® EVA materials are high-grade products consisting of a highly homogeneous and stable cell structure. The desired results can be achieved only when the material is uniformly heated, the recommended temperature is not exceeded, and the cooling times in the mould are observed. This is of particular importance for the thicker Lunatec combi sheets (vulcanised composite EVA).
For successful bonding and thermoplastic moulding, correct heating of EVA materials is decisive. Closed heat sources, such as an oven, are always preferable. So an oven should always be chosen over a one-sided warming on a stovetop. Temperature setting: 130°C | 260°F.
At this setting the material reaches a consistent optimal temperature of 110-130° C | 230-260°F, which varies due to material thickness and density.
Make sure to comply with sufficient cooling times for EVA materials during the heat moulding process.
A rule of thumb suggests: Heating time x factor 2 = optimal cooling time
For ideal permanent bonding, both of the materials to be bonded should be quickly ground or sanded.
Then apply a thin layer of adhesive and allow for drying until there are no visible wet spots anymore. Subsequently, bring the materials together under slight pressure and then press. For the processing of EVA materials adhesives are generally suitable that are based on polychloroprene.
For soft and light materials, such as Lunairmed and Lunairflex, please adapt the pressure in order to avoid compression of the materials, which would impair restoration capability. Find more tips in our application examples.
The materials are generally very easy to grind. The choice of grit should be determined by the softness and elasticity of the material.
We recommend to start grinding with a coarser grit (e.g. granulation 24) before moving on to a finer grit (e.g. granulation 80), to grind insoles or moulded parts to shape.
Frequently Asked Questions (FAQ's)
What does EVA stand for?
EVA stands for the synthetic material ethylene-vinyl-acetate and is a highly valuable raw material, which is used in granulate form in the production of nora® products.
Do expanded rubber sheets contain latex?
No, the expanded rubber sheets from nora® do not contain any latex proteins that might cause allergic reactions for patients.
What are composite sheets?
Composite sheets, vulcanised composite EVA or combi sheets, are compositions of proven nora materials, which means that two or three different nora materials are vulcanised together already during the manufacturing process. As the first manufacturer in the industry we have started with this kind of production method more than 15 years ago, combining the most common material combinations with each other. This is particularly interesting for foot beddings that require a sandwich build up, like the diabetes-adapted footbed. The composite sheets save certain labour steps for the build up with the multilayer sandwich-technique.
What's the benefit of composite sheets vs. single materials?
The use of vulcanised composite EVA sheets is more efficient, because it saves time and money. Two different materials are already bonded together so that no further bonding is necessary. This eliminates the risk of the different materials shifting as they are worked or of bubbles forming at the joint. In addition, there is no hardening due to a bonding layer, and there is greater retention of volume, because no deep drawing is needed.
Which temperature is ideal for warming a Lunatec combi sheet?
The oven should be set to a temperature of 130°C | 260°F. At this setting, the material consistently reaches an optimal temperature of 110-130° C | 230-260°F. Please note the different activation times for Lunatec combi sheets! We would be happy to provide you with tested heating and cooling times.
How long must the material cool after heat moulding on the last?
For the cooling time the recommended rule of thumb is: activation time x factor 2 = optimal cooling time. Through the use of vacuum deep drawing equipment with a cooling system, the cooling process can be accelerated. Note: If the cooling time is too short, formed materials can pull away from the last.
Is it possible to clean an insole with off-the-shelf disinfectant?
Yes. The disinfectability of contaminated footbeds and inserts with a commercially available disinfectant has been verified regularly by the PFI laboratory conducting extensive microbiological tests with precisely defined quantities of bacteria and fungi. Disinfection is successful only on materials with closed cellular structures. Unlike foams with open cellular structures, closed cell surfaces are impenetrable to wound secretions, bacteria, and fungi, which can then be removed with ease. For a cleaning recommendation guideline, please go to our downloads section.
Are there any products that are particularly sustainable?
The products in the Lunatur Walnut range consist for a large part of finely ground walnut shells. The goal of this development was to make practical use of a natural waste product and refine the EVA material with a valuable natural resource.
What does the SG label mean?
The SG label is awarded by approved test institutes after intense material analyses. This test mark confirms that, according to current knowledge, there are no risks to the health of dealers, processors, or patients. It entitles the test institute to take samples at any time from ongoing production and does not constitute a once only test. nora® products are never only tested, but certified. A simple test report does not confirm compliance with the SG mark.
Have your materials been tested for skin compatibility?
Since 1988, nora® materials have been regularly tested for skin compatibility, previously from Institute Fresenius and now from the renowned institute Dermatest.
The dermatological tests are performed on human skin. Through the patch test the material is tested by applying small patches of the material to the skin and after 24, 48 and 72 hours the skin is dermatologically examined.Dermatest describes this test as follows: “The patch test shows any primary irritation or contact dermatitis (by provoking allergic skin reactions in sensitised volunteers). The test substances are applied most of the time occlusively to the skin, i.e. under closed conditions, in appropriate concentrations.”
What does “SG plus” stand for?
SG plus stands for proven disinfectability, outstanding quality under static and dynamic long-term stress, and a certified production site. The SG plus test mark adds microbial and physical tests and monitoring of the production site to the requirements of the eco-label ‘Schadstoffgeprueft’ (SG). This test mark was developed exclusively for nora® products.
Can I receive a REACH Certifiate from you?
All products from nora systems GmbH comply with the regulation (EG) No. 1907/ 2006 (REACH), as it is the applicable law. As it is our knowledge, they do not contain any of the substances of the candidate list (SVHC, cited 07.09.2018) in a concentration of over 0,1 %. We are happy to send you certificates in regards to this topic, of our products that are tested and certified. When it comes to REACH – it is a certification under international standards which is just as much a matter of course as adherence to the pertinent legislation, and therefore followed unquestioningly and without exception!
Do nora® materials have a CE label?
With the CE labelling of products, the complete conformity with the legal regulations is documented, e.g. those of the Medical Devices Ordinance (MDR). It guarantees the free movement of goods and services in the European internal market. This concerns, for instance, over the counter medical products with a defined function. Individual custom-made products are not affected, as they are not freely available in the marketplace but made for the individual person.
Since nora® materials are used in medical products, but are not declared as such, CE marking is not relevant or required. All requirements of the MDR relevant to materials are met by nora® materials. Owing to their properties, nora® materials are suitable for the processing of Class 1 medical products.
When nora® products are used, is it possible to track and trace them?
Yes, the batch numbers printed on the material ensure the necessary reliability for your quality management. The batch number can be used to reproduce the history of product manufacture at any time.
Is it true that CONTITECH belongs to nora®?
In 2001 the repair materials of the brand CONTITECH found a new home in the nora shoe component product range. Regarding the proven quality of CONTITECH heel and outsole materials, nothing has changed. Since then, the items have been integrated into the nora product range and are managed under the brand nora®.
If the last is rough, the unevenness always shows up in the material, how can I prevent this?
For rough lasts, it is recommended to use a test-shoe-foil on the last, which evens out the roughness, making the surface of the material smoother.
Where do I find safety data sheets (SDS)?
Safety data sheets are generally only necessary for chemicals and chemical substances. nora® materials are products that legally do not require safety data sheets. We are happy to provide safety information sheets for you.
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