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The NEWTON relies on warm edge technology from H.B. Fuller | KÖMMERLING

Property developers and employers are increasingly investing in innovative real estate projects that sensibly combine New Work and Zero Waste concepts. A prominent example of such a super-efficient and attractive construction project is the NEWTON in Munich’s Westend, an office property from the TÜV SÜD Gruppe München, completed in 2018. What makes its ultra-modern façade stand out, among other things, are the sophisticated cold-bent, double-curved insulating glass units in the roof dome. To ensure that these meet the high demands for reliable edge-sealing and long-lasting stability, the ultra-high-performance Ködispace 4SG warm edge system from adhesive and sealant manufacturer H.B. Fuller | KÖMMERLING was used.

In recent years, Munich’s Westend has increasingly developed into a popular residential and nightlife area. The successful mix of old and new buildings, small pubs and popular restaurants, as well as the short distances to local recreation areas in and around Munich, make this new trendy neighbourhood especially attractive. At the same time an anprogressive business location has become established which, in addition to the well-known ADAC Tower, the Fraunhofer Institute and other renowned institutions, now boasts he NEWTON as its latest real estate project from the TÜV SÜD Gruppe.

In the NEWTON, a total of close to 35,000 m² of office space in 65 occupancy modules offer ideal conditions for new, forward-looking working environments accommodating up to 2,000 people. The glass-roofed hall forms the main focal point of the building and a forum for events. GEWE-therm 4SG insulating glass from SCHOLLGLAS were used to build the roof dome in the NEWTON. After production and delivery to the construction site, the insulating glass units were bent directly on site by experts from LAMILUX using an assembly and bending method that firstly fixes them to the frame construction diagonally, and then into their final shape.
All edges of the 1,850 x 1,850-millimeter insulating glass units are held in a linear manner using pressure bars and have a maximum corner deflection of 95 millimeters.

In the NEWTON’s double-curved roof dome, the flexible warm edge system with Ködispace 4SG ensures that the cold-bent insulating glass is permanently sealed.
Photo credit: koem_tuev_010.jpg, H.B. Fuller | KÖMMERLING, Martin Lässig
In the NEWTON’s double-curved roof dome, the flexible warm edge system with Ködispace 4SG ensures that the cold-bent insulating glass is permanently sealed. Photo credit: koem_tuev_010.jpg, H.B. Fuller | KÖMMERLING, Martin Lässig

The results clearly showed that, especially with cold-bent insulating glass units, the Ködispace 4SG reactive warm edge system has clear advantages over a conventional spacer bar system. This confirmed that stiffer conventional spacers cannot compensate for the resulting loads for two primary reasons. Firstly, inflexibility of the material and secondly, almost all of the shear load relies on absorption through a very thin PIB (butyl primary sealant) layer, often measuring less than 0.5 millimeters. This in turn leads to large deformations in the primary seal consequently leaks cannot be ruled out as a result.

Due to significantly more flexible behaviour, Ködispace 4SG absorbs the external deformation without creating significant stresses. Ködispace 4SG also uses the entire width and volume of the spacer it creates between the panes – depending on the system this is normally 12 to 20 millimeters compared to two 0.3 to 0.5-millimeter PIB layers in conventional systems – and is therefore much more able to compensate for the occurring loads and associated deformations than a conventional, rigid spacer system. With Ködispace 4SG the resulting deformations are smaller by a factor of about ten in the case detailed above. Additionally, greatly improved gas tightness is achieved with the reactive polyisobutylene chemically bonding to both the glass surface and the silicone secondary sealant. As a result, the entire edge seal “blends” into a flexible and resilient unit that is stable over long term becoming permanently tight. This and the final results of the FEA were confirmed by component tests: data that ultimately convinced both the planning parties and the NEWTON façade builders of the system from specialists H.B. Fuller | KÖMMERLING.

 

Platinum for sustainability

When building the NEWTON, long-term thinking and demonstrating responsible and sustainable design principles were top priorities for the team of architects at DMP, a member of the German Sustainable Building Council since 2008. In addition to the use of intelligent and innovative building materials, the building also stands out with an ecological concept that works with existing resources. Regardless of the season, the building is heated or cooled continuously with groundwater. Moreover, photovoltaics on the roof surfaces enable the use of regenerative solar power, reducing the general electricity requirement by a further 25 percent. The energy requirement itself is also impressive: with a primary energy requirement of approx. 72 kWh/m²a, the NEWTON achieves an absolute peak value, almost a third less than the average for an office building of comparable size. The use of the Ködispace 4SG warm edge system in the construction of the roof dome makes a significant contribution to sustainable construction, as long-term energy-efficient insulating glass units can only be achieved in combination with permanently gas-tight spacer systems. The prudent approach of all those involved in designing the environmental strategy for the building  was recently rewarded with a DGNB platinum certificate awarded for a sustainable building  performing at the highest award level. This puts the NEWTON in the top rankings of Munich’s desirable office properties.

Construction panel

 Project: NEWTON München, Ridlerstrasse 57, Munich

Client: TÜV SÜD AG Munich

Completion: 2018

Architecture firm: DMP Architects Axel Altenberend, Munich

Use: Office, conference and catering

GFA: 61,680 m² (total, incl. 2 basements)

Façade construction: Dodel metal construction and LAMILUX (for the roof construction)

Glass elements: SCHOLLGLAS GEWE-therm® 4SG

Spacer system: H.B. Fuller | KÖMMERLING Ködispace 4SG

 

About Kömmerling Chemische Fabrik GmbH

 Since 2017, Kömmerling Chemische Fabrik GmbH, as H.B. Fuller | KÖMMERLING, has been part of the US adhesives group H.B. Fuller. With its three business units – Engineering Adhesives, Construction Adhesives and Hygiene, Health and Consumable Adhesives – the world’s largest supplier of adhesives and sealants covers a wide range of demanding adhesive and sealant applications used in a number of industries such as electronics, hygiene, medicine, transport, construction and renewable energies. The international group generates sales of some 3 billion US dollars and has 6,500 employees serving customers in more than 125 countries. The Pirmasens site has become the “Technology Center of Excellence” for insulating glass applications and is therefore responsible for research and development of new products and fields of application as well as for advancing existing expertise.

Weitere Informationen und Belegexemplar an:

Kömmerling Chemische Fabrik GmbH
Zweibrücker Str. 200
66954 Pirmasens
Tel: +49 6331 56-2560
Fax: +49 6331 56-1110
E-Mail: alexandra.rohr@hbfuller.com
www.koe-chemie.de

The covered entrance hall is a central meeting point for employees and a popular location for all types of events.
Photo credit: koem_tuev_158.jpg, H.B. Fuller | KÖMMERLING, Martin Lässig
The covered entrance hall is a central meeting point for employees and a popular location for all types of events. Photo credit: koem_tuev_158.jpg, H.B. Fuller | KÖMMERLING, Martin Lässig
The warm edge with Ködispace 4SG compensates for any deformations of the cold-bent insulating glass in the roof dome much better than rigid spacer systems.
Photo credit: koem_tuev_103.jpg, H.B. Fuller | KÖMMERLING, Martin Lässig
The warm edge with Ködispace 4SG compensates for any deformations of the cold-bent insulating glass in the roof dome much better than rigid spacer systems. Photo credit: koem_tuev_103.jpg, H.B. Fuller | KÖMMERLING, Martin Lässig

A first-class warm edge system with Ködispace 4SG

In order to meet the high demands for reliable sealing and long-lasting stability, the building materials and composites used for the construction of the NEWTON were extensively tested in advance. First and foremost the structural integrity of the Ködispace 4SG spacer system for the glass structure in the roof dome was evaluated. To compare the double-glazed insulating glass units to be installed, two digital models were created: one with a Ködispace 4SG spacer system and one with a conventional aluminum spacer. Both models were then examined in detail within the framework of a finite element analysis (FEA) assessing the shear loads in the edge compound system of the planned roof dome caused by the consequent deformation from the bending.

The ideal prerequisite for a state-of-the-art New Work space: open, transparent office structures that can be flexibly combined.
Image: koem_tuev_085.jpg, H.B. Fuller | KÖMMERLING, Martin Lässig
The ideal prerequisite for a state-of-the-art New Work space: open, transparent office structures that can be flexibly combined. Image: koem_tuev_085.jpg, H.B. Fuller | KÖMMERLING, Martin Lässig
The NEWTON’s glass-roofed hall is a main focal point of the building, entrance for the working world of up to 2,000 people as well as a forum for events. Photo credit: koem_tuev_122.jpg, H.B. Fuller | KÖMMERLING, Martin Lässig
The NEWTON’s glass-roofed hall is a main focal point of the building, entrance for the working world of up to 2,000 people as well as a forum for events. Photo credit: koem_tuev_122.jpg, H.B. Fuller | KÖMMERLING, Martin Lässig
Due to its special composition, Ködispace 4SG forms a chemical bond with the glass as well as with the secondary sealant silicone. The insulating glass therefore becomes a firmly bonded yet flexible unit.
Photo credit: H.B. Fuller | KÖMMERLING
Due to its special composition, Ködispace 4SG forms a chemical bond with the glass as well as with the secondary sealant silicone. The insulating glass therefore becomes a firmly bonded yet flexible unit. Photo credit: H.B. Fuller | KÖMMERLING

Bildnachweis: Kömmerling Chemische Fabrik

Quality of support and expertise a key factor for new relationship

Tuffx, one of the country’s leading manufacturers of specialist glass for both the residential and commercial markets, has forged a long-term partnership with Kommerling UK. The latter is providing Tuffx with a range of hotmelts and specialist resins that are being incorporated into several of the company’s market leading products including glass for balustrades, canopies and stair treads.

Paul Higgins, Purchasing Manager at Tuffx, explained more; “Opportunities for laminated products in which the glass has one or more inherent properties eg photovoltaic capabilities or UV protection, are only going to increase as we see glass used in ever more creative ways, in both the commercial and high end residential markets. It became clear that Kommerling could offer us far more than just a high-performance product. From our first meeting the support from both the team here in the UK, backed up by extensive technical and development expertise in Germany has been first class.” He continued; We very much view this as a collaboration where our knowledge of glass manufacturing combined with Kommerling’s unrivalled expertise in the development and production of resins will lead to some exciting new products in the not too distant future.”

Kommerling supplies both its Koedigaurd UV-HS R liquid composite for Tuffx’s structural applications and Isomelt M, a hotmelt, for its IG glass range. Chris Davis, Composites Manager for Kommerling UK, said;” We are delighted to be working with Tuffx, and that they have recognised the true value of our technical and product support. We look forward to fruitful joint technical collaboration on various projects in the coming months that will deliver new products that we believe will extend how and where glass is used and which will excite the architectural community.”

 

The product that Tuffx has introduced on its production line is Koedigaurd UV-HS R liquid composite. With exceptional performance in terms of the strength of the finished bond, combined with quicker processing times and the ability to apply it to bespoke pieces of glass without having to subject them to a lengthy application and curing process, the product is delivering very real benefits in terms of production times. This in turn means that not only are customer lead times reduced but so are direct production costs.

Two examples of Tuffx products

Tuffx_Staircases

Background

Tuffx Processed Glass Ltd, has nearly twenty years’ experience in specialist, toughened safety glass manufacturing. Tuffx is established as one of the UK’s most progressive, customer-oriented companies. The company is based in Knowsley, Merseyside where it employs 156 people. For more information on Tuffx products visit

http://www.tuffxglass.co.uk

 

Koemmerling Chemische Fabrik GmbH is a leading international manufacturer of high-quality adhesives and sealants. Its European headquarters and extensive research and development facilities are in Pirmasens, Germany and it has a network of subsidiaries, sales offices and sales partners, in more than 80 different countries. With over 110 years’ experience, the company has established itself as an innovative market leader in provision of Polysulfide, Polyurethane, Silicone and Polyisobutylene sealants for the automotive, insulating glass and photovoltaic industries. In April 2015, Royal Holdings, Inc. through its Kommerling UK Limited subsidiary, acquired CIL.

 

Koemmerling Chemische Fabrik has been awarded ISO 9001, ISO 14001 ISO 50001 and OHSAS 18001 certification.

To find out more, Aboutcamp BtoB interviewed Iñaki Sigler - Marketing Manager, Durable Assembly - EIMEA at H.B. Fuller, and Ralf Fuhrmann - Business Manager, Transportation Adhesives & Aftermarket at Kömmerling Chemische Fabrik GmbH, an H.B. Fuller company.

H.B. Fuller is a major industrial adhesives manufacturer with factories and customers worldwide. It is headquartered in Minnesota, U.S. The recent acquisition of Royal Adhesives brought its annual turnover to $2.3 billion and included the Kömmerling brand and technology.

Aboutcamp BtoB: What has been the driver to bring these two companies together for the RV market in Europe?

Iñaki: H.B. Fuller has acquired Royal's business globally. In Europe, this means Kömmerling, and we now operate as a single company.

Ralf: Both H.B. Fuller and Kömmerling have been supplying the same market but with little overlap between their products. For example, H.B. Fuller was well known for its range of adhesives for sandwich panels and furniture, and Kömmerling is well known for its sealants and adhesives for assembly bonding and interior finishing. It was really quite amazing how our products complemented each other, a perfect fit you might say. The acquisition has, therefore, provided the opportunity to offer a one-stop solution for all RV manufacturers. This means the one company can now supply all the sealants and adhesives needed by the RV industry where previously this was not possible.

Aboutcamp BtoB: Did you each have RV manufacturer customers already in Europe?

Ralf: Yes, we did. I was hired some 20 years ago by Kömmerling to develop the RV sector and have been doing so ever since, together with an international team in the relevant European market. Beside this, H.B. Fuller has been in the RV market for more than 30 years.

Aboutcamp BtoB: How big do you think the European market is?

Ralf: Looking at RV production numbers, the European market is very large. Indeed, we jointly supply some 1,000 tonnes of adhesives and sealants each year. We have many customers with both large production operations but also with independent single producers. So, we are already a big player in the market, and we definitely want to grow further.

Aboutcamp BtoB: Do you also sell these products outside Europe, for example to the U.S. or Australia?

Ralf: We are a global company, and we have production sites and colleagues around the world, but Kömmerling has only a small presence outside Europe. We sell to the Australian market, and a couple of years ago, we began to manufacture and sell in China. We see this as a market with excellent growth potential.

Aboutcamp BtoB: Presumably you see yourselves as competitors to Henkel, Sika, Deka and so on?

Ralf: Exactly! Competition is strong, and we are now in a better position to expand our business than ever before, as we are now able to supply every single technology needed for production of high quality recreational vehicles.

Aboutcamp BtoB: What about new applications and products? Hwo do you go about testing to ensure fitness for purpose?

Ralf: Having a product for every conceivable RV application is key to the success of the new venture, and as new applications arise, we will commence dialogue with our client's technical teams and purchasing departments to better understand their requirements. Once we have a specific request, we discuss it face to face to understand the application and what environmental or other conditions might influence the joint line. Extensive testing is then carried out on the original customer substrates according to the conditions in which the new application will be used. Only once we are 100-percent happy is the new product or application released for production. But it's not only RV manufacturers we talk to about new applications. With new materials constantly coming to the market, we stay ahead of the game by talking directly to RV material suppliers and by testing samples before anything goes into production.

Aboutcamp BtoB: Which is your best-selling product in the RV market?

Ralf: Both parts of the business - legacy H.B. Fuller and Kömmerling - have strong product applications. H.B. Fuller was very strong in the sandwich panel fabrication and furniture markets, and these adhesives remain best sellers. Twenty years ago one-part polyurethane solutions dominated the market in other areas, but Kömmerling came along with a range of silane-terminated polymers and marketed these across the European RV sector. Isocyanate and solvent-free solutions have good adhesion on a wide range of substrate materials, and they offer good temperature and UV resistance. Today, these products are amongst our best sellers.

Aboutcamp BtoB: How is the adhesives industry evolving? For example, we hear quite a bit about 'Hot Melt'. Is this a process that's gaining ground?

Iñaki: There are different solutions to meet different needs. For example, there are thermoplastic hot melt and reactive hot melt in use. H.B. Fuller is very strong in both types of technology, but in the sandwich element fabrication market, one- or two-component, liquid reactive adhesives dominate. Some years ago, the use of reactive hot melt adhesives was analyzed for this application in order to speed up fabrication times. With reactive hot melt, it's ready to go as soon as it's cool, whereas with liquid reactive adhesives, pressure over time is needed for the chemical reaction to take place. We have very good reactive hot melt solutions, though we work closely with customers to determine the right solution. What we do is align our proudcts very closely to the conditions our customers have or want to implement. If they are liquid reactive proudcts and our customers want to change a line, we work with them from the beginning to adjust our formulations to give maximum performance under the new conditions.

Ralf: Unlike the non-reactive thermoplastic hot melts, reactive hot melt adhesive is transformed into an infusible bond, making it more resistant to high temperatures and, therefore, more durable. In Europe, reactive hot melt technology is not widely used with sandwich panel production. It is seen more often in the U.S. market.

Iñaki: That's very true. We do supply reactive and thermoplastic hot melt adhesives to factories worldwide - high quality furniture manufacturing is one example and is an application field in RV industries as well.

©Kömmerling Chemische Fabrik GmbH

Ralf Fuhrmann

"We are delighted to be part of this exciting opportunity. Our name is already well established in the RV sector in Europe, and now, with the backing of H.B. Fuller and its complementary product range, we can offer our customers new technologies and even better value. We look forward to the challenges ahead and to working with our customers to solve them."

Iñaki Sigler

"Combining these two businesses allows us to offer our RV customers new technologies, expertise and capabilities. For the first time, we can submit problem-solving passion that has been our hallmark. We will continue to discover and apply innovations in adhesive technology and to help our customers excel in this area."

Company profile

H.B. Fuller

From a one-man wallpaper paste shop in Minnesota in 1887, H.B. Fuller has grown into a $2.3 billion adhesives global leader today. Its recent acquisition of Royal, further strengthens its market reach as teh two companies have very little customer or product overlap. Nowhere is this more evident than with Royal's European brand, Kömmerling, a major supplier to the RV industry in Europe.

 

Kömmerling

Headquartered in Pirmasens, some 170 km south west of Frankfurt, and founded in 1897, Kömmerling is a leading international manufacturer of high-quality adhesives and sealants. In this capacity, it has been supplying the RV industry in Europe and beyond for more than 20 years. It became a member of H.B. Fuller's global network through the company's acquisition of Royal Adhesives & Sealants in October 2017.

Source: Aboutcamp BtoB, issue June 2018

Kommerling warm edge system, Ködispace 4SG, has been used in a recent extension to the Gösta Serlachius Museum in Finland. The Gosta Pavilion is the latest addition to the home of the industrialist and art collector, Gosta Serlachius. Designed by Spanish architect, MX-SI, the extension’s structure consists of 100 parallel laminated timber frames, interspersed by high windows.

The pavilion, which took 18 months to construct, is 135m long and 17m high at its maximum height. It is joined to the Serlachius private family residence, a brick house with a copper roof, by a glass corridor. The addition of this new building has reportedly increased the museum space by 500m², to a total of 1.500m², and it houses both a permanent exhibition of the Gost Serlachius art collection alongside varying exhibitions by both Finnish and international artists.

The warm edge system

The silicone-sealed glass panels in the project were manufactured by Finnish company, Seloy, with specialist sealant made by Kommerling. The bonded elements conceal a special warm-edge system, which thanks to flexible edging, is said to be equal to the wild temperature extremes of the local climate. At the heart of the sealing process is a separator called Ködispace 4SG.

According to Kommerling, the warm-edge system menas that insulation panes are ‘extraordinarily’ robust, resilient and durable and also ideally suited for the physical requirements of structural glazing.

Glass with aesthetic properties

Ködispace 4SG is said to considerably enhance the aesthetic properties of glass elements; there are no ‘ugly’ separator displacements in the three-ply insulation panes or disruptive light reflections that can be caused by metal parts. The black sealant ensures that the space between panes is almost invisible and sight lines from within the museum are unhindered, giving the impression of a ‘fluid transition’ between the building and its surroundings.

finland-b

finland-a

Q&A with Dr. Knut Göke, product manager at KÖMMERLING Chemische Fabrik GmbH

GGP: What sort of problems can arise with glass facades?

KG: The extreme temperatures occurring in the faces cause the insulation glass to expand and pull together again, thus exposing the edging to enormous stresses. If the sealant is not able to accommodate this movement and instead compensates for them, the seal becomes leaky, hence elasticity of the sealant is a significant precondition for permanently, well-sealed insulation glass. If the seal cannot be maintained then there is a risk of loss of gas and thermal insulation. Material incompatibility among the adhesives and sealants used and in interactions between construction materials deployed can also cause additional problem, which in the worst case scenario can lead to expensive and hazardous structural damage.

GGP: Why is Ködispace 4SG so well suited to structural glazing?

KG: Black polyisobutylene is extruded from the barrel direct on to the disc to create a well-sealed, homogeneous separator. In the process it replaces primary sealant, metallic separator and desiccant. Its special formulation allows it to form a chemical bond with the glass and secondary sealant silicone. The overall edging remains permanently elastic and gas-tight over the long term. Kommerling also offers suitable secondary sealants that are fully compatible and thus provide a reliable and safe warm-edge system.

GGP: How has this sealant benefited the Gosta pavilion?

KG: Serious cold puts additional strain on glass. The warm edges of Ködispace 4SG are great at surviving the severe sub zero temperatures of the Finnish winter without any problems. It is clear that this climate places great demands on thermal glass insulation and its durability. Without the appearance of an unsightly separator, the warm edge approach allows the interesting architectural design to deliver maximum impact.

Source: Glass & Glazing Products, issue October 2016

The last crime figures show that the police registered exactly 167,136 burglaries in Germany last year. Which means that another flat is ransacked every three minutes on average. Doors and windows are frequently exploited vulnerabilities for break-ins. But the protection from burglars can be markedly improved by gluing.

The annual number of burglaries has been on the increase again for a while, most recently by nearly 10 percent in 2015. The perpetrators very often break into flats and houses by prying open a window. A simple screwdriver will suffice to do this with standard windows. Leverage is applied to design-related vulnerabilities: the connections between the glazing and casement, between the casement and window frame, and between the window frame and wall.

Tested resistance classes

A remedy is provided by anti-burglary windows with demonstrably tested resistance classes. Which is also why the police is recommending components rated RC2 or higher. But a window will only prevent intrusion if the safety chain formed by the bonding of the glass, rebate area and connection to the wall is completely closed and the entire system meets the requirements of the desired resistance class.

Glued all around

What this means for the glass bonding is that glass strips need to be screwed or glued in place to make the grade. A far better solution for this is to glue the insulating glass into the casement, however, because the circumferential bond will fuse them into a single entity.

Only a small number of glazing blocks will now be required for load transfer, if any at all. This eliminates a leverage point for prying the window open at the glass joint. The gluing additionally improves the statics of the entire casement, which is rendered torsion-resistant and virtually impossible to twist. The consequence: A burglary tool applied to only a single point of the window will be unable to gain enough leverage for bending the casement. The gluing hence not only strengthens the glass joint, but indirectly also the connection between the casement and window frame.

The recommended RC2 resistance class is furthermore reached with particular ease if the insulating glass is glued to the casement. This offers tangible advantages for window makers and fitters: The blocking is reduced or even done away with entirely, with no separate fastening of glass strips required. All the window needs now is the right RC2 fitting, and appropriate installation at the building site. In addition, this can also be done using profiles with no additional steel reinforcements.

Polyurethane glue meets the requirements

To be recommended as an optimal antiburglary solution is the gluing position at the base of the rebate with a polyurethane adhesive called Ködiglaze P from Kömmerling. This can not only be used for RC-gluing to plastic profiles, but also all the other commonly used frame materials such as wood, wood/aluminium and aluminium, for example. The glue is available in a one-component version in 600 ml sausages or also in a two-component version for application with mixing and dispensing systems.

Glued to the rebate base

The bonding with the rebate base achieves the best statics: As opposed to glass edge bonding, the casement will not require additional overlaps for reinforcement. The PUR adhesive furthermore achieves a high mechanical stability and is hard to cut. It can even be used to provide RC2-compliant fixed glazing directly at the building site. The one-component adhesive is easy to handle, enabling the insulating glass to be glued into the ready-assembled frame on site without difficulties.

To ensure a permanently secure bond, the manufacturer’s adhesives are compatible with most insulating glass sealants available on the market. This also means that they are attuned to the commonly used polysulphide- or polyurethane-based insulating glass sealants in their chemical as well as mechanical properties. These materials are furthermore compatible with the commercially available PVB films used to increase the glazing’s anti-burglary effect from resistance class RC2.

 

koemmerling-logo

The polyurethane adhesive can not only be used on plastic to meet the RC requirements, but also on all other commonly found frame materials
such as wood, wood/aluminium and aluminium, for example.

 

Source: Adhesion, The Trade Journal for Industrial Adhesives and Sealants, 3/2016 Vol. 13

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