glue

Area	Manufacturing process joining
title	glue
Brief description:	Classification, subdivision, terms
Latest edition	2003-09
ISO

The bonding is a manufacturing process from the main group joining . Like welding and soldering , gluing is one of the integral joining processes. Gluing is used to connect parts to be joined together using glue .

history

Even if gluing as a joining process is closely linked to the development of plastics - most of the adhesives used today are naturally plastics - it is a very old joining process. First evidence for the use of birch pitch shows that as early as 220,000 years ago birch pitch was obtained from birch bark by dry distillation and used as an adhesive for the manufacture of tools. Further examples of the history of gluing can be found under glue.

Basics

Universal adhesive

The force-transmitting effect of an adhesive is based on the interplay of adhesion - the ability of a material to build up adhesive forces on the surface of another material - and cohesion - the internal strength of the (solidified) adhesive.

adhesion

The interactions that form the adhesion between the adhesive and the surface of the part to be joined have an extremely short range of less than 1 nanometer . Therefore, good wetting of the parts to be joined by the not yet solidified, i.e. liquid adhesive is a necessary prerequisite for the production of a high-quality bond. In addition to being able to be wetted, the adhesive and the part to be joined must have groups of molecules that match each other, so that an interaction between the adhesive and the part's surface and thus adhesion can occur.

The adhesive forces are mostly based on physical interactions, such as B. on those between polar or polarizable groups, on hydrogen bonds or the so-called van der Waals forces. Diffusion processes can also occur when bonding plastics, in particular with solvent-based adhesives . The plastic is loosened on the surface of the part to be joined by the solvent contained in the adhesive. This leads to an increased mobility of the polymer chains, which in turn allows penetration of the polymer chains of the joining part with those of the adhesive. Ultimately, additional interactions develop between the polymer chains of the adhesive and the part to be joined. After the solvent has evaporated, a solid bond is created. Chemical bonds are required for certain component-adhesive combinations, e.g. B. when gluing glass with silicone adhesives, wood with polyurethane adhesives or aluminum with epoxy adhesives is also possible. Compared to physical interactions, chemical interactions lead to significantly higher adhesive forces. In addition, penetration of the liquid adhesive into undercuts after it has hardened can result in a certain additional form fit that increases strength .

Since the creation of adhesive forces between the adhesive and the surface of the joining part not only requires an adhesive composition that is suitable for the respective joining part material, but also places high demands on the joining part surface, this is of great importance for bonding. So it is clear that due to the small range of the adhesive forces, the nature of the outermost surface layer is decisive. This must also be sufficiently firmly connected to the subsurface; Many adhesives adhere very well to a corroded steel surface, but the corrosion layer - the rust - is not firmly attached to the substrate. When loaded, failure occurs in the corroded material or between the rust layer and the unchanged steel. The same applies to coated parts to be joined. Here the coating represents the surface to which the adhesive has to build up adhesion. The coating, in turn, must be firmly bonded to the substrate.

In the same way, impurities, especially those which, due to their low surface tension, counteract wetting by the adhesive (e.g. oils, release agents, etc.), prevent the formation of the interactions that make adhesion. Impurities form, so to speak, a barrier between the adhesive and the surface of the part to be joined, which the adhesive forces cannot bridge due to their limited range.

Therefore, contamination must usually be removed before gluing. The rule of thumb is: not as clean as possible, but as clean as necessary. Some special adhesives show a certain compatibility with certain oils. They are able to absorb certain oils during the hardening of the adhesive, which takes place at elevated temperatures, and thus remove them from the boundary layer between the adhesive and the part to be joined. Such adhesives are z. B. used in the body shop of the automotive industry. They allow sheet metal parts with corrosion protection and drawing oils to be glued without first cleaning them; The adhesive is hardened in the following ovens required for the hardening of the lacquer at temperatures between approx. 150 and 200 ° C.

Solidification of the adhesive - cohesion

As the adhesive solidifies, its internal strength, the cohesion , increases. The cohesion is also based on physical interactions, here between the individual adhesive polymers. In the case of adhesives that cure through a chemical reaction, i.e. the formation of the polymers through a chemical reaction of the adhesive components, the chemical bonds that arise play an important role.

Properties of a bond

The cohesion and adhesion properties of the adhesive, in conjunction with the part to be joined, determine the properties of a bond. While the adhesion properties essentially determine whether an adhesive sticks (adheres) to a component to be joined, the cohesion properties make a major contribution to the mechanical properties of the bond, in particular the deformation behavior under load.

It must be taken into account that adhesive connections are not only subject to a certain aging, but their properties are dependent on the respective environmental conditions, in particular the temperature. Both the adhesion-forming interactions between adhesive and joining part, as well as the inter- intramolecular interactions causing cohesion can be adversely affected by external influences (including temperature, humidity, chemicals, radiation, mechanical stress). The extent of the impairment depends on the type of conditions and their duration; the process is known as aging. When planning a bond, not only the real environmental conditions but also their possible long-term effects must be taken into account.

Due to the large number of influencing parameters and sometimes conflicting requirements for adhesive connections, it is easy to understand that the so-called “all-round adhesive” cannot exist. In this context, it should be noted that, contrary to the common usage, the term “adhesive” describes the material that connects parts to be joined through the interplay of adhesion and cohesion . The “glue”, on the other hand, is the person who creates the glue.

Adhesive selection

Important criteria to consider when choosing an adhesive

The selection of a suitable adhesive for a special application should be based on a specific requirement profile. In this requirement profile, all direct, verifiable requirements for the component to be bonded and the resulting bond and adhesive are listed. A distinction can be made between requirements that must be met and those that are advantageous but not absolutely necessary. Requirements from the bonding process, including those from upstream and downstream process steps, must also be taken into account. The figure on the right gives, without claiming to be exhaustive, an overview of the most important parameters to be considered when choosing an adhesive.

Advantages and disadvantages of gluing

Advantages of gluing

The main advantages are:

Almost all materials can be bonded to themselves or other materials;
Due to the two-dimensional force transmission, an even distribution of the forces over the entire adhesive surface is achieved. This allows optimal use of the properties of the joining part;
By choosing a correspondingly large adhesive surface, relatively high forces can also be transmitted between thin parts to be joined, which is particularly advantageous for lightweight construction applications;
by choosing an elastic adhesive, movements of the parts to be joined relative to one another can be compensated for, e.g. For example, expansion of the joining part can be compensated for in the event of temperature fluctuations and vibrations can be effectively damped, thus avoiding material damage or material fatigue of the joining part;
There is no material damage to the parts to be joined by drilling holes for z. B. rivets or screws;
visually appealing surfaces can be realized;

There is little or no thermal load associated with gluing, so that thermal distortion, thermal stresses or changes in the microstructure and consequently a change in the mechanical properties of the materials to be joined are largely avoided;
Joint tolerances can be compensated by means of gap-bridging adhesives
Gluing is equally suitable for both small and large parts. In microelectronics, for example, the amount of adhesive per component is Sometimes just a few micrograms, while the manufacture of rotor blades for wind turbines requires several hundred kilograms per component.
In addition to the power transmission, additional properties such as B.
- sealing connection
- acoustic decoupling, damping
- electrical insulation (avoidance of contact corrosion)
- electrically conductive
- thermally insulating
- thermally conductive (thermal management for electronic components)

to get integrated.

Disadvantages of gluing

Disadvantages are e.g. B .:

as a rule, immediate strength is not achieved. The pressure-sensitive adhesives, which are often used in the form of double-sided adhesive tapes, the fast-curing cyanoacrylates , often also referred to as " instant adhesives " , and many light-curing adhesives achieve a certain initial strength after the joining process has been completed or very shortly thereafter, if not yet their final strength that is sufficient to further process the glued assembly;
Depending on the chemical basis, adhesive connections have limited thermal and chemical resistance / resistance;
the mechanical properties of the bond are temperature dependent;
Adhesives show e.g. T. a certain tendency to creep;
the long-term stability of a bond is subject to aging processes;
a releasability of the connection is often not possible without damaging at least one of the parts to be joined;
Gluing is a so-called “special process”, ie a test cannot be fully realized using non-destructive methods. Therefore, the bonding process must be mastered to avoid errors. DIN 2304-1 (Adhesive Bonding Technology - Quality Requirements for Adhesive Processes - Part: 1: Adhesive Process Chain) defines the requirements for a high-quality execution of load-transferring adhesive joints along the adhesive process chain - from development through production to rework;
Many adhesives and auxiliary materials required for the bonding process (solvents for cleaning, primers) are hazardous substances and require appropriate precautionary measures when handling.

Comparison of the joining processes

The disadvantage of the lack of immediate strength with many adhesives can be achieved by combining them with a second, fast-curing adhesive (e.g. double-sided adhesive tape) or with another joining method, e.g. B. spot welding , riveting , screwing , or clinching can be compensated. In this process, known as hybrid joining, the flat connection of the parts to be joined between the other joining points leads to a significant reduction in the stress peaks at these joining points, and immediate strength is achieved.

Applications (selection)

Modern adhesives have become indispensable in today's life. They can be found in a variety of everyday products as well as in specialty products. Here are some examples from different areas:

Stamp

See also: postage stamp

The history of the postage stamp, which was first introduced in the Kingdom of Bavaria in 1849, is closely linked to adhesives. At that time the postage stamp adhesive consisted of naturally occurring raw materials such as sugar molasses, potato starch and occasionally isinglass, but showed significant weaknesses. The stamps either stuck together or fell off prematurely and had a penetrating odor. In addition, the stamps had to be moistened before sticking, which was often done by licking. However, due to the unpleasant taste, this was rather unpopular. With the development of synthetic adhesives, it was possible in the middle of the 20th century to switch to the use of tasteless and odorless adhesives made from polyvinyl acetate or polyvinyl alcohol. This also solved the problem of sticking and falling off prematurely. Today more and more stamps are offered that do not require moistening. These self-adhesive postage stamps are coated on the back with a pressure-sensitive adhesive and only have to be peeled off from a carrier provided with a non-stick coating before they can, for B. be stuck on a letter.

Automotive industry

The manufacture of modern cars would not be possible without adhesives, here are two examples:

Windshield

Today's windshields are made of laminated safety glass, which consists of two or more panes of glass bonded with a tear-resistant, tough-elastic, transparent hot-melt adhesive film. This film provides u. a. to ensure that the pane remains connected as a unit after a break, thus minimizing the risk of injury from broken glass. While the windshields used to be attached to the body by means of a rubber seal, today they are firmly glued in and are a structural component of the body. This is only possible through the use of an adhesive that is adapted to the application in terms of its mechanical properties. On the one hand, the adhesive offers sufficient strength to securely connect the window to the body and, on the other hand, is sufficiently elastic to protect the B. to compensate for relative movements between the body and the window during driving, so to prevent glass breakage. Since the glued-in windshield contributes to the rigidity of the body, thinner sheet metal can be used in certain areas in body construction, thereby reducing the vehicle weight and ultimately the energy consumption.

Vehicle electronics

The introduction of more and more electronics in motor vehicles, from engine controls to safety components such as ABS and ESP and driver assistance systems to elements that increase comfort, would also not be possible without modern adhesives. Given the small size of e.g. B. control devices, sensors, cameras etc. one quickly reaches its limits with conventional joining processes. Therefore, the components used today are glued to a large extent.

In order to ensure proper functioning of the control units and the associated sensors, which are increasingly performing safety-related tasks, the electronics must be protected from external influences such as e.g. B. moisture, salt, fuel and other operating materials are safely protected. Many sensors are therefore encapsulated or are protected by absolutely tight housings. In both cases, adhesives are used. When potting components, a bubble-free potting must be achieved and the hardened potting material must have sufficient media resistance as well as a certain mechanical stability in order to withstand the abrasive loads caused by sand and split bombardment during driving. On the other hand, it must have sufficient elasticity to avoid that it is in the z. Sometimes sudden temperature changes due to the different thermal expansion behavior of the materials involved lead to tensions and, as a consequence, to leaks or to the tearing of soldered connections and thus to failure.

The steadily increasing number of electronic components also increases the risk of mutual interference due to insufficient electromagnetic compatibility (EMC). To ensure the EMC, z. B. Metal housing used in which the cover is glued on by means of adhesives containing special fillers. This guarantees the required EMC in addition to the required tightness.

Home appliance industry

Similar to the automotive industry, adhesives are also used in the manufacture of household appliances for a large number of bonds with very different requirements. For example, temperature-stable silicone adhesives are used in the manufacture of ceramic hobs or the fastening of the viewing window in oven doors. The connections must withstand temperatures of up to 250 ° C and of course must not release any harmful substances. Membrane keyboards as operating elements as well as the labeling panels for conventional operating elements are attached to the devices by means of double-sided adhesive tapes , such as B. stoves and ovens, refrigerators, washing machines, tumble dryers attached.

But glue is also used in the manufacture of small electrical appliances. So z. B. in coffee machines, the plastic handle is often glued to the jug body made of glass. Compared to fastening using a metal clamping ring, gluing offers advantages in production by avoiding glass breakage. Another advantage is that during use, dirt particles can accumulate between the can body and the clamping ring and moisture can hold for a long time, which in the long term can lead to corrosion of the clamping ring and thus to an unattractive appearance, which can no longer occur with an adhesive solution without a clamping ring. Adhesives based on polyurethane or silicone are used, either as a 2K system or moisture-curing. The adhesives must u. a. have sufficient strength over the entire service life of the coffee machine even at temperatures of up to 100 ° C, be dishwasher-safe and have sufficient elasticity to compensate for the different thermal expansion behavior of glass and the plastic material of the handle and thus prevent glass breakage.

The production of all-round devices that have various functions in one device, such as B. Combining cooking, stirring, kneading, mixing and grinding would not be possible in today's form without modern adhesives. The heart of such devices is z. B. an extremely powerful, brushless electric motor. To z. B. To crush nuts, high speeds are required, whereas kneading cake dough requires high torques at low speeds. Since the devices are also suitable for cooking, an appropriate temperature resistance is required. Light-curing adhesives ensure that the rotor and stator, the two essential components of the motor, form a solid unit. The hardening of the adhesive takes place within a very short time, so that large quantities can be produced cost-effectively. During curing, the photoinitiators contained in the adhesive are initially formed under the influence of light and highly reactive molecules which in turn cause the chemical curing process of the adhesive resin.

Packaging industry

Most deep-freeze and microwave packaging today consist of biodegradable film composites. Of course, the adhesives used to manufacture these film composites must also be biodegradable. This is achieved through the use of molecules similar to those of naturally occurring polymers, such as. B. cellulose and starch, are similar and can be broken down by microorganisms with the help of enzymes to water, carbon dioxide and biomass.

Medicine and medical technology

In medicine and medical technology, adhesives play an increasingly important role. On the one hand, a plaster is required to adhere well to a wide variety of skin types and, on the other hand, to be removed as painlessly as possible. In addition, some plasters z. B. release medical active ingredient as a transdermal patch over a longer period of time through the skin into the bloodstream and others partly for the long-term attachment of sensors z. B. can be used for the continuous measurement of the blood sugar level on the skin. These plasters have to stick securely for up to 14 days, even under e.g. T. extreme conditions such. B. when showering, when going to a swimming pool or sauna and when doing sport. Corresponding skin tolerance is a matter of course. Special pressure-sensitive adhesives based on both acrylates and synthetic rubber are used as adhesives .

In surgery, adhesives are used to treat certain surgical wounds. These adhesives are mostly based on fibrin , the natural ( adhesive ) substance that causes blood to clot when injured. As the body's own substance, this has the advantage that the adhesive is not repelled by the body. In addition, it degrades by itself over time, which eliminates the need for time-consuming post-treatment such as pulling threads from a seam. This property is particularly important in interventions on the heart or the gastrointestinal tract.

Medical bonding is most advanced in dentistry. Adhesives are not only used for filling cavities and the production of dentures, but also help in orthodontics. The so-called brackets, through which the wires of a fixed tooth bracket are pulled, are attached to the teeth using special adhesives. On the one hand, the brackets should hold securely in the moist and warm environment of the oral cavity, which is critical from the adhesive point of view, but should later be removable without leaving any residue.

Adhesives have also proven themselves in medical technology. This is how the needles of syringes are usually glued into place. The stainless steel cannula must be securely connected to the adapter, which is often made of plastic. Due to the high number of items, short cycle times are required. Light- curing adhesives are often used that achieve sufficient strength after just a few seconds of exposure to light of a certain wavelength and also withstand the subsequent sterilization process using superheated steam, ethylene oxide or gamma radiation without damage.

The manufacture of endoscopes, where u. a. Tension-free attachment of lenses with ever smaller dimensions is also a good example of the performance of modern adhesives. In addition to the strength, it is important to compensate for the different thermal expansions of the joining partners. In this case, no voltages that affect the image quality may be transferred from the lens holder to the lens.

Adhesive standardization, training and further education

With the increasing use of adhesive technology in industry and trade and the resulting increasing demands on the quality and durability of the bonded products , a comprehensive set of national and international standards and the like arose, similar to other joining processes with high requirements. a. for characterization, classification and testing of adhesives or bonded joints.

Since gluing is only part of the vocational training in a few professions and then only the adhesive processes relevant to the respective profession are taught, there was a need for qualifying further training measures for personnel who are involved in the development, manufacture and repair of glued products. This need was met with the introduction of a three-stage training concept. The advanced training to become an adhesive practitioner , adhesive specialist and adhesive engineer is defined in the harmonized guidelines of DVS (for Germany) and EWF (for Europe). With the DVS guideline DVS-3310, which was published in 2003 and revised in 2012, the operational requirements for adhesive bonding processes were described for the first time. In 2007, with the publication of the DIN 6701 series of standards (bonding of rail vehicles and vehicle parts), a regulation came into force for the first time, with which the quality standards of bonding technology user companies for rail vehicle construction and construction specifications as well as implementation rules and quality assurance of bonding processes were specified. With DIN 2304-1 (Bonding technology - Quality requirements for bonding processes - Part: 1: Bonding process chain) published in March 2016, the state-of-the-art for the professional execution of all load-transferring bonded joints across industries and products as well as for all adhesive classes and material combinations became for the first time in one German standard established. The standard regulates the technical and organizational quality assurance in the production of adhesive joints along the bonding process chain, from development through production to any necessary rework or repair.

Surface pretreatment

The most important processes for surface pretreatment (according to H. Gleich)

The adhesive strength of the bond can be greatly increased in many applications, in particular by cleaning , degreasing , roughening and coating with an adhesion promoter (primer), which forms a better bond with the component than the actual adhesive.

The parts to be connected are usually first cleaned, dried and degreased with solvents . For highly stressed bonds , the surfaces are also pretreated by flame treatment , low-pressure or normal-pressure plasma treatment and corona discharge technology . Some plastics cannot be bonded at all without these processes or the use of adhesion promoters.

Surfaces that have been pretreated by cleaning may have to be protected from corrosive influences from the surrounding atmosphere. For example, they can be preserved by applying adhesion promoters or glued immediately. Metallic materials tend to oxidize . Under certain circumstances, they can be preserved with anti-corrosion oil if the adhesive used is compatible with oil. Otherwise, the reaction layers that form must be removed, provided they do not adhere firmly to the starting material as well as to the adhesive.

Physical procedures

Aqueous cleaners

Aqueous cleaners are usually made slightly alkaline . If necessary, acidic cleaners and neutral cleaners can also be used.

Wiping, dipping or spraying processes can be used. Emulsifiers improve the cleaning effect on non-polar contaminants such as fats and oils. The heating of the cleaning solution to 40 ° C to 90 ° C and the use of brushes or ultrasound ( cavitation ) also improve the cleaning effect .

Solvent-based cleaners

Solvent-based cleaners are also used in wiping, dipping and spraying processes and also in vapor degreasing , in which the components to be cleaned are placed in a chamber with boiling solvent. The evaporated solvent condenses on the component and carries the dissolved impurities back into the boiling sump, where they remain while the cleaning agent evaporates and condenses again.

Rays

When blasting , the surface is cleaned and roughened at the same time by the impact of the abrasive (e.g. corundum or glass balls). The abrasive is accelerated by compressed air or a centrifugal wheel and can also remove stubborn deposits and oxide layers. The removed particles remain in the blasting agent, which must therefore be replaced or processed regularly.

Due to the resulting frictional heat and tribochemical processes, components of the blasting agent can react with the component surface or cling to it, which can reduce the adhesion of the adhesive.

Occasionally, substances are deliberately added to the abrasive that chemically change the surface.

Physically thermal processes

Treatment with plasma jet (e.g. with low pressure plasma , atmospheric pressure plasma or corona treatment )

Flame

Laser pre-treatment

Ion etching / sputtering

Flame

A flame is applied to plastics by directing a flame past the surface at an even distance and speed. The ratio of fuel gas to oxygen must also be kept constant. Depending on the plastic, the flame is set to be reducing or oxidizing. With flame coating , the surface is pretreated by applying reactive substances that are added to the flame.

Flaming cannot replace the cleaning of the workpiece, rather it serves to transform the material of the surface. Excessive heating of the component surface can lead to the formation of undesirable layers that have a separating effect.

Physico-chemical processes

Adhesion promoters, primers, activators

Adhesion promoters work in a similar way to adhesives, but are usually only applied very thinly and dry before the actual adhesive is applied and the components are joined together.

Adhesion promoters are primarily used when different materials are to be joined that cannot be joined with the same adhesive. In rare cases, they allow the use of an adhesive with special properties, which, however, does not readily adhere to the desired substrate, and improve the durability of the bond.

Adhesion promoters protect cleaned surfaces from oxidation and the formation of different types of reaction layers, can contain various reactive groups for the component to be joined and the adhesive, and may wet the surface of the substrate better than the adhesive itself.

Excimer ozone

The high-energy UV radiation of the xenon excimer stimulates molecular bonds on the surface of the adhesive surface and oxygen molecules in the surrounding atmosphere are converted to ozone . Oxygen atoms react with the bonds, cleanse and diffuse into the surface. This increases the surface energy and the wettability of the surface by the adhesive, which is what makes the bonding of difficult materials possible in the first place.

literature

Walter Brockmann among others: Bonding technology. Adhesives, Applications and Processes. Wiley-VCH, Weinheim 2005, ISBN 3-527-31091-6 .

Hermann Onusseit: practical knowledge of adhesive technology. Volume 1: Basics. Hüthig, 2008, ISBN 978-3-410-21459-5 .

Manfred Rasche: Manual Bonding Technology. Carl Hanser Verlag, Munich / Vienna, ISBN 978-3-446-42402-9 .

Wilhelm Finally: Adhesives and sealants in modern technology. Practical manual for adhesive and sealant application. Vulkan-Verlag, Essen 1998, ISBN 3-8027-2183-7 .

Gerhard Gierenz, Frank Röhmer: Adhesives. Gluing and Adhesives Workbook. Cornelsen-Verlag, Düsseldorf 1991, ISBN 3-590-12939-5 .

Gerd habenicht: Gluing. Basics, technology, applications. Springer, Heidelberg 2005, ISBN 3-540-26273-3 .

Gerd habenicht: Gluing - successful and error-free. Vieweg, Wiesbaden 2003, ISBN 3-528-24969-2 .

Industrieverband Klebstoffe e. V .: Handbook Bonding Technology. Vieweg, Wiesbaden 2016, ISBN 978-3-658-14529-3 .

Industrial Association for Adhesives V., Fonds der Chemischen Industrie im VCI e. V .: Teaching Material Adhesives - The Art of Gluing. Chemical Industry Fund

Elastic bonding. Modern industry publishing house, Landsberg / Lech 1998, ISBN 3-478-93192-4 .

Elastic bonding on construction. Modern industry publishing house, Landsberg / Lech 2001, ISBN 3-478-93245-9 . (Basic knowledge with the know-how of leading companies)

Karl F Berger, Sandra Kiefer (ed.): Seal Technology Yearbook 2007. ISGATEC, 2006, ISBN 3-9811509-0-2 .

BOND it - reference work on adhesive technology. DELO Industrial Adhesives, 2007, ISBN 978-3-00-020649-8 .

DVS-3310 Quality requirements in adhesive technology. DVS Media, February 2012. (Guideline)

DIN 6701 bonding of rail vehicles and vehicle parts. Beuth-Verlag, Berlin, 2007. (Standard)

Detlef Symietz, Andreas Lutz: Structural bonding in vehicle construction. Properties, applications and performance of a new joining process. (= The Library of Technology. Volume 291). Verlag Moderne Industrie, 2006, ISBN 3-937889-43-4 , pp. 7-13, p. 27, p. 37, p. 68.

DIN 2304-1 Bonding technology - Quality requirements for bonding processes. Part 1: process chain. Kleben Beuth-Verlag, Berlin 2016.

Individual evidence

↑ Paul Peter Anthony Mazza, Fabio Martini, Benedetto Sala et al: A new Palaeolithic discovery: tar-hafted stone tools in a European Mid-Pleistocene bone-bearing bed. In: Journal of Archaeological Science. Volume 33, No. 9, 2006, pp. 1310-1318.

↑ Horst Stepanski: Spot weld bonding in automobile construction . In: Adhesion: glue & seal . 5/2010 and 6/2010. Vieweg + Teubner - Springer Fachmedien, Wiesbaden 2010.

↑ H. Kollek: The adhesion mechanisms . In: O.-D. Hennemann, W. Brockmann, H. Kollek (Eds.): Handbook Manufacturing Technology Gluing . Carl Hanser, Munich / Vienna 1992, ISBN 3-446-17165-7 , pp. 209 ff .

↑ DIN 2304-1: 2016 Bonding Technology - Quality requirements for bonding processes - Part: 1: Bonding process chain . Beuth Verlag, Berlin 2016.

↑ Stamp gumming - the sticky secret is revealed . In: Industrieverband Klebstoffe e. V. (Ed.): Gluing for life . May 2015, p. 36 f . ( kleben-fuers-leben.de ).

↑ Windshield - glued holds better . In: Industrieverband Klebstoffe e. V. (Ed.): Gluing for life . No. 5/2016 , p. 26th f . ( kleben-fuers-leben.de ).

↑ Cooking has never been so easy - a revolution in the kitchen world . In: Industrieverband Klebstoffe e. V. (Ed.): Gluing for life . May 2016, p. 43 f .

↑ Adhesion: glue & seal . No. 7-8 / 2017 . Springer Vieweg, Wiesbaden, p. 47 .

↑ Organic packaging - on the compost instead of in the bin . In: Industrieverband Klebstoffe e. V. (Ed.): Gluing for life . May 2016, p. 42 .

↑ Active substance intake via plaster - no more injections . In: Industrial Association of Adhesives (Ed.): Gluing for life . May 2011, p. 24 .

↑ Medicine / technology - glue instead of needle and thread . In: Industrieverband Klebstoffe e. V. (Ed.): Gluing for life . May 2015, p. 29 .

↑ DVS - German Association for Welding and Allied Processes V. (Ed.): DVS guideline DVS 3311 . May 2012.

↑ Bonding of rail vehicles and vehicle parts . Beuth Verlag, Berlin 2007.

↑ DIN 2304-1: 2016 Bonding Technology - Quality requirements for bonding processes - Part: 1: Bonding process chain . Beuth Verlag, Berlin.

↑ Henning Gleich, Andreas Hartwig, Hartwig Lohse: Why pre-treatment is so important . In: Adhesion: glue & seal . No. 9/2016 . Springer Vieweg, Wiesbaden, p. 34 ff .

↑ iot-gmbh.de: Excirad 172 surface treatment

Web links

Industrial Association for Adhesives V. klebstoffe.com

[1] Paul Peter Anthony Mazza, Fabio Martini, Benedetto Sala et al: A new Palaeolithic discovery: tar-hafted stone tools in a European Mid-Pleistocene bone-bearing bed. In: Journal of Archaeological Science. Volume 33, No. 9, 2006, pp. 1310-1318.