Two-component composition for the production of an aqueous coating mass

Description

[0001] The invention relates to a two-component composition that can be converted into an aqueous, hydraulically curable preparation usable as an encapsulating compound by mixing with water. The aqueous encapsulating compound can be used to produce a hydraulically cured encapsulation of an electronic component.

[0002] The term "electronic component" used herein includes, in addition to passive electronic components, semiconductor modules and, among the latter, in particular power electronic assemblies.

[0003] Semiconductor modules are understood herein to be electronic or power electronic assemblies comprising at least one substrate (as a circuit carrier), at least one semiconductor component (semiconductor), and optionally at least one passive electronic component. The at least one semiconductor component may itself be partially or completely pre-encapsulated, for example, with an epoxy resin-based coating.

[0004] Examples of substrates are IMS substrates (insulated metal substrates), DCB substrates (direct copper bonded substrates), AMB substrates (active metal brazing substrates), ceramic substrates, metal-ceramic substrates, PCBs (printed circuit boards) and leadframes.

[0005] Examples of semiconductor components include diodes, LEDs (light-emitting diodes), dies (semiconductor chips), IGBTs (insulated-gate bipolar transistors), ICs (integrated circuits), and MOSFETs (metal-oxide semiconductor field-effect transistors). The semiconductor component(s) are, in particular, semiconductors that generate considerable heat during intended operation due to power dissipation, i.e., they reach self-destructive temperatures of, for example, 100 to > 200°C without a casing and unencapsulated.

[0006] Examples of passive electronic components include sensors, base plates, heat sinks, resistors, capacitors, transformers, chokes and inductors.

[0007] The term "hydraulic curing" as used herein includes setting in the presence of water or after the addition of water.

[0008] GB 2 186 227 A discloses a two-component system usable for producing a hardenable cement comprising as a first component an aqueous solution comprising phosphoric acid, aluminum dihydrogen phosphate and alkali, alkaline earth or aluminum salt of an acid at least as strong as phosphoric acid and as a second component a metal oxide hardener such as magnesium oxide.

[0009] US 2015 / 239784 A1 discloses hardenable cements suitable for sealing deep-sea boreholes, which can be prepared by mixing a liquid, aqueous mixture comprising magnesium oxide with a second liquid, aqueous mixture comprising phosphoric acid or hydrogen phosphate.

[0010] Powdered compositions and aqueous coating compositions in the form of phosphate cement that can be produced therefrom are disclosed, for example, in WO 2015 / 193035 A1. Coatings for electronic components made from such aqueous phosphate cement coating compositions serve, in particular, to provide electrical insulation and dissipate heat from the electronic component to the outside during operation.

[0011] As has surprisingly been shown and can be seen from the following disclosure, it is particularly expedient with regard to the production of aqueous phosphate cement coating compositions and their use for the production of coatings, in particular coatings of electronic components, on an industrial scale to provide compositions from which aqueous preparations usable as phosphate cement coating compositions can be produced as a two-component system.

[0012] The invention relates to a composition as defined in claim 1.

[0013] The composition consisting of the components (a) to (c) or (a) to (d) is thus in the form of two components, ie different and separate components (components to be stored separately or stored separately).

[0014] In other words, the invention relates to a system of two different components comprising no more than the following components: (a) 1 to 30 wt.% of at least one hydrogen phosphate selected from the group consisting of mono- and dihydrogen phosphates of sodium, potassium, magnesium, calcium, aluminum, zinc, iron, cobalt and copper, (b) 1 to 40 wt.% of at least one compound selected from the group consisting of oxides, hydroxides and oxide hydrates of magnesium, calcium, iron, zinc and copper, (c) 40 to 95 wt.-% of at least one particulate filler selected from the group consisting of glass; mono-, oligo- and polyphosphates of magnesium, calcium, barium and aluminum; calcium sulfate; barium sulfate; simple and complex silicates comprising sodium, potassium, calcium, aluminum, magnesium, iron and / or zirconium; simple and complex aluminates comprising sodium, potassium, calcium, magnesium and / or zirconium; simple and complex titanates comprising sodium, potassium, calcium, aluminum, magnesium, barium and / or zirconium; simple and complex zirconates comprising sodium, potassium, calcium, aluminum, magnesium, barium and / or zirconium; simple and complex zirconates comprising sodium, potassium, calcium, aluminum and / or magnesium; zirconium dioxide; titanium dioxide; aluminum oxide; silicon dioxide; silicon carbide; aluminum nitride; boron nitride and silicon nitride, and (d) 0 to 25 wt.% of at least one component other than components (a) to (c). wherein the weight proportions of components (a) to (c) and (a) to (d) respectively add up to 100 wt.%, wherein the complex silicates, complex aluminates, complex titanates and complex zirconates are silicates, aluminates, titanates and zirconates with more than one type of cation, wherein component (a) can comprise up to 10 wt.% of free water which is not bound as water of crystallization in the at least one hydrogen phosphate, based on the total component (a), wherein component (d) can comprise up to 10 wt.% water, based on the total component (d), wherein components (a) and (b) are present separately from one another.

[0015] The invention thus relates to a two-component composition consisting of said components (a) to (c) and, if present, also (d). The components together comprise all components (a) to (c) or (a) to (d). The components are stored separately from one another until they are used to produce an aqueous, hydraulically curable preparation comprising all components (a) to (c) or (a) to (d). The production of such a preparation requires the addition of, or mixing with, water.

[0016] Each of the components (a) to (d) may comprise one or more different ingredients, hereinafter also referred to as sub-components.

[0017] To avoid confusion, a distinction is made herein between components (a) to (d), subcomponents of these components and components of the two-component composition according to the invention.

[0018] Constituent (a), which makes up 1 to 30 wt. %, preferably 2 to 15 wt. %, of the two-component composition according to the invention, is at least one substance selected from the group consisting of sodium monohydrogen phosphate, potassium monohydrogen phosphate, magnesium monohydrogen phosphate, calcium monohydrogen phosphate, aluminum monohydrogen phosphate, zinc monohydrogen phosphate, iron monohydrogen phosphate, cobalt monohydrogen phosphate, copper monohydrogen phosphate, sodium dihydrogen phosphate, potassium dihydrogen phosphate, magnesium dihydrogen phosphate, calcium dihydrogen phosphate, aluminum dihydrogen phosphate, zinc dihydrogen phosphate, iron dihydrogen phosphate, cobalt dihydrogen phosphate, and copper dihydrogen phosphate. In other words, it is at least one hydrogen phosphate selected from the group consisting of mono- and dihydrogen phosphates of sodium, potassium, magnesium, calcium, aluminum, zinc, iron, cobalt, and copper.In particular, it is at least one hydrogen phosphate selected from the group consisting of mono- and dihydrogen phosphates of magnesium, potassium and aluminum.

[0019] Component (a) or its subcomponents are preferably solid particles, for example with particle sizes in the range of up to 1 mm.

[0020] Component (a) can contain up to 10% by weight of free water, based on the total component (a). With regard to component (a), free water is water that is not bound as water of crystallization in the at least one hydrogen phosphate. Component (a) preferably comprises no water, or at least no free water. In particular, component (a) preferably does not comprise deliberately added water.

[0021] Constituent (b), which makes up 1 to 40 wt. %, preferably 2 to 15 wt. %, of the two-component composition according to the invention, is at least one compound selected from the group consisting of oxides, hydroxides, and oxide hydrates of magnesium, calcium, iron, zinc, and copper, in particular at least one compound selected from the group consisting of magnesium oxide, iron oxide, and calcium oxide. Magnesium oxide is particularly preferred.

[0022] Preferably, component (b) or its subcomponents are solid particles, for example with particle sizes in the range of up to 0.3 mm.

[0023] Component (b) does not contain free water and preferably also does not contain bound water. Water that can be expelled from oxide hydrates at elevated temperatures is not considered bound water.

[0024] Constituent (c), which makes up 40 to 95% by weight, preferably 65 to 90% by weight, of the two-component composition according to the invention, is at least one particulate filler selected from the group consisting of glass; mono-, oligo- and polyphosphates of magnesium, calcium, barium and aluminum; calcium sulfate; barium sulfate; simple and complex silicates comprising sodium, potassium, calcium, aluminum, magnesium, iron and / or zirconium; simple and complex aluminates comprising sodium, potassium, calcium, magnesium and / or zirconium; simple and complex titanates comprising sodium, potassium, calcium, aluminum, magnesium, barium and / or zirconium; simple and complex zirconates comprising sodium, potassium, calcium, aluminum, magnesium, barium and / or zirconium; simple and complex zirconates comprising sodium, potassium, calcium, aluminum and / or magnesium; zirconium dioxide; titanium dioxide; aluminum oxide; silicon dioxide, in particular in the form of silicic acid and quartz; silicon carbide; aluminum nitride; boron nitride and silicon nitride.Zirconium silicate, silica and quartz are preferred.

[0025] The previous paragraph mentions mono-, oligo- and polyphosphates; to avoid any misunderstanding, these are phosphates that do not contain hydrogen, unlike the hydrogen phosphates of component (a).

[0026] In the previous paragraph, a distinction is made between simple and complex silicates, aluminates, titanates, and zirconates. Complex representatives are not complex compounds; rather, they refer to silicates, aluminates, titanates, and zirconates with more than one type of cation, such as sodium aluminum silicate, calcium aluminum silicate, lead zirconate titanate, etc.

[0027] The particle sizes of component (c) or its subcomponents are, for example, in the range from 20 nm to 0.3 mm or even from 20 nm to 1 mm.

[0028] Component (c) does not contain any free water and preferably also no bound water.

[0029] Component (d), which makes up 0 to 25 wt. %, preferably 0 to 15 wt. % or 2 to 15 wt. % of the two-component composition according to the invention, is at least one component or subcomponent different from components (a) to (c). Examples include, in particular, additives such as flow improvers, setting retarders (pot life extenders), defoamers, wetting agents, and adhesion promoters. Component (d) can comprise up to 10 wt. % water, based on the total component (d). Component (d) preferably comprises no water, or more precisely, no intentionally added water.

[0030] Component (d) or its subcomponents are preferably solid particles, for example, with particle sizes in the range of up to 0.3 mm or even up to 1 mm. It is possible, although not preferred, that component (d) is not solid, but rather, for example, liquid, or comprises non-solid, for example, liquid, subcomponents.

[0031] The following table illustrates some formulation examples of preferred embodiments of two-component compositions according to the invention. ingredient Embodiment 1 Embodiment 2 Embodiment 3 (a), in particular potassium and / or aluminum dihydrogen phosphate 3 - 9 wt.% 6 - 12 wt.% 12 - 23 wt.% (b), in particular magnesium oxide 3 - 8 wt.% 5 - 14 wt.% 8 - 19 wt.% (c), in particular zirconium silicate 70 - 90 wt.% 55 - 80 wt.% 45 - 65 wt.% (d) 0 - 13 wt.% 9 - 19 wt.% 13 - 25 wt.%

[0032] The two-component composition according to the invention consists of components (a) to (c) or (a) to (d), i.e., the weight percentages of the components add up to 100 weight percent of the two-component composition according to the invention. If no component (d) is present, the weight percentages of components (a) to (c) add up to 100 weight percent of the two-component composition according to the invention.

[0033] In one embodiment, the components of the two-component system according to the invention are present in a ready-to-use amount corresponding to the aforementioned quantitative ratio of the components (a) to (c) or (a) to (d), in other words, ready-portioned and thus immediately mixable with one another to form the one-component composition or additionally with water to form the aqueous hydraulically curable preparation without weighing or measuring.

[0034] The two components of the two-component composition according to the invention, which are to be mixed with one another and with water to form the aqueous, hydraulically curable preparation, are preferably provided in particulate form, for example in powder form. More than one, i.e., comprising two or more different constituents and / or subconstituents, particulate or powdery components of the two-component system according to the invention are present as an intimate mixture, in particular as a stochastically homogeneous mixture; such particulate components preferably exhibit no clumping and are free-flowing.

[0035] Particulate components of the two-component composition according to the invention can be produced by conventional processes known to those skilled in the art for producing free-flowing particulate compositions. Examples of production processes include tumble mixing, intensive mixing, dry grinding, and air blending.

[0036] As already mentioned, the components of the two-component composition according to the invention can be mixed with one another and with water to form an aqueous hydraulically curable preparation.

[0037] An aqueous hydraulically curable preparation, in particular an aqueous hydraulically curable preparation usable as an aqueous coating compound—i.e., a ready-to-use aqueous hydraulically curable preparation—can be obtained by mixing the components of the two-component composition according to the invention into one or more premixes, followed by subsequent mixing with water. For example, all components of the two-component system according to the invention can first be mixed without the addition of water and then with water to form the aqueous hydraulically curable preparation.

[0038] Alternatively, at least one of the components of the two-component composition according to the invention can first be mixed with water, thus converting it into at least one aqueous intermediate. The result is a two-component system that differs from the original two-component system (a two-component system derived from the original two-component system; also referred to as a "derived two-component system" for short), comprising the at least one aqueous intermediate and any remaining component of the original two-component system that is not mixed with water. The components of the derived two-component system thus formed can therefore be mixed directly or with the addition of water to form an aqueous hydraulically curable preparation, in particular to form an aqueous hydraulically curable preparation that can be used as an aqueous coating composition—that is, a finished aqueous hydraulically curable preparation.

[0039] A derived two-component system may in particular take the following embodiments (i), (ii) or (iii): (i) A derived two-component system comprising an aqueous component in the form of an aqueous intermediate A' comprising component (a) without any portions of component (b) and a further aqueous component in the form of an aqueous intermediate B' comprising component (b) without any portions of component (a). Such an aqueous intermediate A' is characterized by a virtually unlimited storage life, whereas the storage life of such an aqueous intermediate B' generally does not exceed 48 hours.In the case of a derived two-component system of type (i), its two aqueous and, for example, liquid or pasty components can be mixed by means of a suitable two-component mixing system, for example by means of a static mixer (in particular of the Kenics or Ross ISG mixer type), to form an aqueous hydraulically curable preparation, in particular an aqueous hydraulically curable preparation usable as an aqueous coating compound - i.e., a finished aqueous hydraulically curable preparation, in particular in the context of industrial series production, for example, a series production of corresponding coatings or coated electronic components. Such use of the derived two-component system of type (i) is particularly suitable for implementation by the end user, i.e., by the user of the aqueous hydraulically curable preparation, in particular an aqueous hydraulically curable preparation usable as an aqueous coating compound - i.e., a finished aqueous hydraulically curable preparation.(ii) A derived two-component system comprising a non-aqueous component comprising component (a) without any portions of component (b) and an aqueous component in the form of an aqueous intermediate comprising component (b) without any portions of component (a). As mentioned above, such an aqueous intermediate is characterized by a storage life of generally no more than 48 hours. An end user can convert this derived two-component system of type (ii) into a derived two-component system of type (i) by converting the non-aqueous component comprising component (a) without any portions of component (b) by mixing it with water. (iii) A derived two-component system comprising an aqueous component comprising component (a) without any portions of component (b) and a non-aqueous component comprising component (b) without any portions of component (a).The end user can convert this derived two-component system of type (iii) into a derived two-component system of type (i) by converting the non-aqueous component comprising component (b) without any portion of component (a) by mixing with water.

[0040] In general, an aqueous hydraulically curable preparation of the type in question does not contain an excess of acid; in other words, the basic component (b) can generally be selected in type and amount such that the acid equivalents provided by component (a) and any further acid equivalents from components (c) and (d) can be at least completely neutralised, preferably over-neutralised.

[0041] For example, a total of 100 parts by weight of the components, for example preferably particulate components, of the two-component composition according to the invention can be mixed with 5 to 30 parts by weight, preferably 6 to 15 parts by weight of water to form the aqueous hydraulically curable preparation.

[0042] As stated, it is possible to first mix all components of the two-component system according to the invention with one another without the addition of water and then to mix them with water to form the aqueous, hydraulically curable preparation. However, it is preferred to first mix at least one of the components with water to form at least one aqueous intermediate, thus creating a derived two-component system. Further mixing with the other component and / or the other aqueous intermediate can then take place.

[0043] When preparing the aqueous, hydraulically curable preparation using the two-component composition according to the invention, its individual components and the water can be mixed together in any order, optionally also in portions. It is possible to first prepare intermediates in the form of one or more of the aforementioned two-component premixes without the addition of water and / or in the form of the aforementioned aqueous intermediates with the addition of water. Aqueous intermediates may optionally be aqueous solutions, for example, aqueous solutions of components (a) or (d) or any subcomponents thereof.It may be expedient to prepare aqueous intermediates comprising component (b) and proportions of at least one acidic component (forming H3O+< ions in the presence of water) selected from components (a), (c) and (d) no longer than, for example, 2 to 24 hours before the final mixing to form the finished aqueous hydraulically curable preparation. The same applies to aqueous intermediates comprising component (b) or subcomponents of component (b) but free of acidic components or subcomponents; here it is expedient to prepare such aqueous intermediates no longer than, for example, 48 hours before the final mixing to form the aqueous hydraulically curable preparation.

[0044] Examples of dynamic mixing processes that can be used in the final mixing to form the aqueous hydraulically curable preparation using the two-component composition according to the invention are stirring and intensive mixing, for example intensive mixing using planetary mixers.

[0045] In an embodiment that is particularly useful with regard to use of the two-component composition according to the invention on an industrial scale, the composition comprises only two components A and B. Component A comprises component (a) and component B comprises component (b). Components (a) and (b) can thus be kept separate from one another during storage of the two-component system according to the invention. Components (c) and (d) can be present in component A and / or B, with preference being given to at least component (c) being present in approximately equal proportions in both components A and B. For example, 30 to 70% by weight, preferably 40 to 60% by weight, of component (c) can be present in component A and the remaining proportion in component B. It can further be preferred that component B does not contain any proportions of any acidic components (c) and (d).Any such acidic substances are preferably contained exclusively in component A. Mixing with water to form the aqueous hydraulically curable preparation can be carried out following the aforementioned principles. However, it is preferred to convert both components A and B, each with water, into a derived two-component system of the aforementioned type (i) comprising aqueous intermediates A' and B' and then mix these together to form the aqueous hydraulically curable preparation. This offers particular advantages with regard to use on an industrial scale. An aqueous intermediate A' comprising component A or component (a) without any portions of component (b) has a virtually unlimited storage life. An aqueous intermediate B' free of acidic substances and comprising component B or component (b) can generally be stored for at least 48 hours.Preferably, the aqueous intermediates A' and B' can be formulated such that, with regard to their mixing ratio, they have similar volumes, for example volumes differing from one another by no more than 20% (corresponding to a volume ratio of 1.2:1 to 1:1.2) and / or comparable rheological properties, for example viscosities in the range of 0.5 to 50 Pa s (rotational viscometry, plate-plate measuring principle, plate diameter 25 mm, measuring gap 1 mm, sample temperature 20°C, shear rate 36 min -1< , viscosity value determined after a measuring time of 2 minutes).A mixture of both aqueous intermediates A' and B' represents an aqueous hydraulically curable preparation in the aforementioned sense, brings components A and B and thus components (a) and (b) into contact with one another and has a pot life (processing period, duration of processability) expressed as the time until the initial viscosity (viscosity after 5 minutes calculated from the first contact of the two-component composition according to the invention and water) doubles, generally up to 120 minutes.It is therefore expedient to provide the two aqueous intermediates A' and B' separately and in a larger total amount, generally within a period of 48 hours, and to mix the required portions of aqueous intermediates A' and B' prior to use for encapsulating electronic components, for example immediately or no longer than 120 minutes, preferably no longer than 10 minutes, beforehand. Examples of two-component mixing systems that are not only usable in this context but are particularly suitable are the aforementioned static mixers, the outlet opening of which releases the aqueous hydraulically curable preparation in the form of the aqueous intermediates A' and B' sufficiently homogeneously mixed with one another in the desired mixing ratio, continuously or in portions in the required amount for the intended use for encapsulating, in particular, electronic components.For example, the desired mixing ratio of the aqueous intermediates A' and B' can expediently correspond to the above-mentioned desired ratio of the two-component composition according to the invention and water, for example the above-mentioned ratio of 100 parts by weight of the two-component composition according to the invention: 5 to 30 parts by weight, preferably 6 to 15 parts by weight of water.

[0046] As already mentioned, the aqueous, flowable, and hydraulically curable preparation can be used as an aqueous encapsulating compound for electronic components. For the sake of brevity, the term "aqueous encapsulating compound" will be used below.

[0047] The aqueous encapsulation compound can be used to produce a hydraulically cured encapsulation for electronic components. The process for producing a hydraulically cured encapsulation for an electronic component, carried out on an industrial scale within the framework of industrial series production, is defined in claim 6; it comprises the steps: (1) Providing an electronic component to be encased, (2) Providing an aqueous encapsulating compound in the form of an aqueous hydraulically curable preparation produced by mixing the components of a composition as defined in any one of claims 1 to 5 with one another and with water, wherein each of the two components of the two-component system is first mixed with water to form an aqueous intermediate before further mixing takes place, (3) Encapsulating the electronic component provided in step (1) with the aqueous encapsulating compound provided in step (2), and (4) Hydraulically curing the aqueous encapsulating compound enclosing the electronic component after completion of step (3).

[0048] The steps (1) to (4) or the process comprising the steps (1) to (4) are carried out on an industrial scale, ie in the context of industrial series production.

[0049] In step (1), an electronic component to be encased is provided, namely a passive electronic component or a semiconductor module, the latter in particular in the form of a power electronic assembly.

[0050] With regard to step (2), reference is made to the above, whereby each of the two components of the two-component system is first mixed with water to form an aqueous intermediate before further mixing. Step (2), implemented on an industrial scale, is carried out by mixing aqueous intermediates A' and B' of a derived two-component system of type (i) using a static mixer, in particular a Kenics or Ross ISG mixer. Step (2) comprises the following substeps: (2a) Providing a two-component composition according to the invention as defined in any one of claims 1 to 5, comprising a first component A comprising component (a) and a second component B comprising component (b), (2b) separately mixing each of components A and B with water to form two separate aqueous intermediates A' and B', and (2c) mixing the aqueous intermediates A' and B' by means of a static mixer to form an aqueous coating composition in the form of an aqueous, hydraulically curable preparation. It is preferred that the two aqueous intermediates A' and B' have volumes that differ from one another by no more than 20% and / or each have a viscosity in the range of 0.5 to 50 Pa s (rotational viscometry, plate-plate measuring principle, plate diameter 25 mm, measuring gap 1 mm, sample temperature 20°C, shear rate 36 min -1<, viscosity value determined after a measuring time of 2 minutes).

[0051] Preferably, step (3) is carried out immediately, for example within 120 minutes, preferably within 10 minutes after completion of step (2).

[0052] In step (3), the electronic component prepared in step (1) is encapsulated with the aqueous encapsulating compound prepared in step (2). Preferred application methods are potting, dipping, and injection molding. Potting can be carried out using conventional methods known to those skilled in the art, for example, by gravity, pressure-assisted, or reduced-pressure potting. It may be expedient to enclose the electronic component to be encapsulated with half-shell molds and then fill it with the pourable encapsulating compound. Encapsulation can be carried out as partial or complete encapsulation. For example, when encapsulating a semiconductor module, the encapsulating compound can partially or completely enclose electrical contacting elements connected to the semiconductor component, such as bonding wires, ribbons, and / or a substrate.Partial encapsulation means that one or more of the contacting elements are incompletely encapsulated and / or one or more of the contacting elements are not encapsulated, while complete encapsulation means that all contacting elements are completely encapsulated. However, encapsulation can also be carried out, for example, in such a way that the encapsulation compound forms a "glob-top" structure, as is known to those skilled in the art.

[0053] In step (4), which follows step (3), the aqueous encapsulating compound enclosing the electronic component is hydraulically cured. More precisely, the essential part of the hydraulic curing, including setting, takes place during step (4); of course, hydraulic curing begins as soon as components (a) and (b) come into contact with each other in the presence of water, i.e., already during step (2). During and after the actual setting, drying, meaning the removal of water or the water itself, can occur. Setting and drying can take place for, for example, 30 to 300 minutes in a temperature range of, for example, 20 to 300°C.

[0054] In the case of working with half-shell molds in step (3), the encapsulated electronic component can be removed from the half-shells after hydraulic curing according to step (4) and opening the latter. Examples General implementation:

[0055] The powdered solid compositions described in the table below were weighed accordingly for each component in a screw-top beaker. After closing the beaker, each component was individually homogenized manually by shaking and then added to water placed in another beaker. The mixture was homogenized to form an aqueous intermediate within 5 minutes by vigorous stirring. The mixing ratio for each aqueous intermediate was 100 parts by weight of solid composition: 10 parts by weight of water. The resulting aqueous intermediates were placed in the measuring cell of a rheometer, and the respective initial viscosity was determined as described above. The two aqueous intermediates were then combined in the specified mass ratio and homogenized to form an aqueous coating mass by vigorous stirring.This was placed in the measuring cell of the rheometer, and the pot life was determined according to the instructions in the previous description. Example 1 Example 2 ingredient Component A Component B Component A Component B (a) Potassium dihydrogen phosphate 3,84 0 3,84 0 (b) Magnesium oxide D 50 = 18 µm 0 4,6 0 4,6 (c) Zirconium silicate D 50 = 10 µm 19,4 17,92 21,3 16 (d1) Urea 2,4 3,6 2,4 3,6 (d2) L-tartaric acid 0,36 2,04 0,36 2,04 (d3) Trisodium citrate trihydrate 0,36 2,04 0,36 2,04 Relative mass fraction of the aqueous intermediate 1 1,13 1 1 Initial viscosity of the aqueous intermediate [Pa s] 2 4 2 2,5 Shelf life of component B 50 h 50 h Pot life of the coating compound 50 minutes 50 minutes D 50 = mean particle diameter

Claims

1. A composition consisting of the following constituents: (a) 1 to 30 wt.% of at least one hydrogen phosphate selected from the group consisting of mono- and dihydrogen phosphates of sodium, potassium, magnesium, calcium, aluminum, zinc, iron, cobalt and copper, (b) 1 to 40 wt.% of at least one compound selected from the group consisting of oxides, hydroxides and oxide hydrates of magnesium, calcium, iron, zinc and copper, (c) 40 to 95 wt.% of at least one particulate filler selected from the group consisting of glass, mono-, oligo- and polyphosphates of magnesium, calcium, barium, and aluminum; calcium sulfate; barium sulfate; simple and complex silicates comprising sodium, potassium, calcium, aluminum, magnesium, iron and / or zirconium; simple and complex aluminates comprising sodium, potassium, calcium, magnesium, and / or zirconium; simple and complex titanates comprising sodium, potassium, calcium, aluminum, magnesium, barium and / or zirconium; simple and complex zirconates comprising sodium, potassium, calcium, aluminum, and / or magnesium; zirconium dioxide; titanium dioxide; aluminum oxide; silicon dioxide; silicon carbide; aluminum nitride; boron nitride and silicon nitride, and (d) 0 to 25 wt.% of at least one constituent other than constituents (a) to (c), wherein the weight proportions of constituents (a) to (c) or (a) to (d) add up to 100 wt.%, wherein complex silicates, complex aluminates, complex titanates and complex zirconates are silicates, aluminates, titanates and zirconates with more than one type of cation, wherein constituent (a) may comprise up to 10 wt.% of free water which is not bound as crystal water in the at least one hydrogen phosphate, based on the total constituent (a), wherein constituent (d) may comprise up to 10 wt.% of water, based on the total constituent (d), wherein the composition is present as a two-component system, and wherein constituents (a) and (b) are present separately from one another.

2. The composition according to claim 1, wherein constituent (a) is at least one hydrogen phosphate selected from the group consisting of mono- and dihydrogen phosphates of magnesium, potassium and aluminum.

3. The composition according to claim 1 or 2, wherein constituent (b) is at least one compound selected from the group consisting of magnesium oxide, iron oxide and calcium oxide.

4. The composition according to any of the preceding claims, wherein constituent (c) is at least one particulate filler selected from the group consisting of zirconium silicate, silica and quartz.

5. The composition according to any of the preceding claims, wherein the components of the two-component system are present in a quantity corresponding to the quantitative ratio of constituents (a) to (d).

6. A method carried out on an industrial scale in the context of industrial series production for producing a hydraulically cured encapsulation of an electronic component, comprising the following steps: (1) providing an electronic component to be encapsulated, (2) providing an aqueous encapsulation compound in the form of an aqueous hydraulically curable preparation prepared by mixing the components of a composition according to any of claims 1 to 5 with one another and with water, wherein each of the two components of the two-component system is first mixed with water to form an aqueous intermediate before further mixing takes place, (3) encapsulating the electronic component provided in step (1) with the aqueous encapsulation compound provided in step (2), and (4) hydraulically curing the aqueous encapsulation compound encapsulating the electronic component after completion of step (3), wherein the electronic component to be encapsulated is a passive electronic component or a semiconductor module, wherein step (2) comprises the following substeps: (2a) providing a two-component composition according to any of claims 1 to 5 consisting of a first component A comprising constituent (a) and a second component B comprising constituent (b), (2b) separately mixing each of components A and B with water to form two separate aqueous intermediates A' and B', and (2c) mixing the aqueous intermediates A' and B' by means of a static mixer to form an aqueous encapsulation compound in the form of the aqueous hydraulically curable preparation.

7. The method according to claim 6, wherein the two aqueous intermediates A' and B' have volumes which differ from one another by no more than 20% and / or each have a viscosity in the range of from 0.5 to 50 Pa.s, wherein the viscosity values are viscosity values determined by means of rotational viscometry using the plate-plate measuring principle with a plate diameter of 25 mm, a measuring gap of 1 mm, a sample temperature of 20°C and a shear rate of 36 min-1 after a measurement period of 2 minutes.