Silicone impression material with accelerated curing

Abstract

The invention relates to a curable composition, more particularly cross-linkable composition, comprising addition-cross-linkable terminal ethylene-group-containing polydialkyl siloxanes and Si-H-group-containing polydialkyl siloxanes having a specific Si-H group content in relation to ethylene groups.

Description

[0001] Silicone impression material with accelerated setting

[0002] The invention relates to a curable composition comprising addition-crosslinkable polydialkylsiloxanes containing at least two terminal ethylene groups and polydialkylsiloxanes containing at least two Si-H groups with a specific content of Si-H groups in the molar ratio to ethylene groups.

[0003] Dental impression materials are typically used to depict the spatial situation of the teeth and jaw. Depending on the type of impression, the impression material placed in an impression tray remains in the patient's mouth for varying lengths of time. Many patients find this step very unpleasant, as it can impair breathing, among other things. This can result in gagging or anxiety, and may even lead to the impression being aborted. The aim is to accelerate the curing of an impression material and thus shorten the time it remains in the patient's mouth. At the same time, a working time must be maintained so that the impression materials can be mixed and applied. Furthermore, a high level of detail in the impression must be achieved. To achieve this, these impression materials must flow as well as possible to the tooth and surrounding tissue, even in the moist oral environment.

[0004] WO 2013 / 025494 A1 discloses addition-curing silicone impression materials consisting of hydride-functional and vinyl-terminated siloxanes that crosslink under Pt catalysis. The impression materials heat up due to the addition of low-molecular-weight allylsilanes during the crosslinking process. These allylsilanes are also already added in US Pat. No. 7,700,712 B2. This heating is caused by a reaction of the allylsilanes with the hydride-functional siloxanes contained in addition-curing silicones. WO 2013 / 025494 A1 states that this heating results in a shortened setting reaction.

[0005] However, the added allylsilanes are associated with two inherent disadvantages due to their low molecular weight. The reaction of allylsilanes with hydride-functional siloxanes is very efficient, which, according to WO 2013 / 025494 A1, can result in a temperature increase of up to 20 °C. In our opinion, this is likely to be perceived as unpleasant or threatening by patients and can trigger anxiety or defensive reactions. Furthermore, the allylsilanes used are monofunctional and therefore cannot contribute to the formation of a silicone network, i.e., effective curing or crosslinking. The object of the invention was to provide curable compositions of addition-curing polysiloxanes that set more quickly within a defined time window and yet are easily processable within this time window.In particular, the compositions should not exhibit any unpleasant temperature rise despite rapid setting. A temperature rise of greater than or equal to 10 °C is considered unpleasant. Furthermore, the impression materials should still exhibit high detail accuracy and flow well to the tooth and surrounding tissue in the moist oral environment.

[0006] The objects were achieved by an addition-curing composition according to claim 1. Preferred embodiments are disclosed in the subclaims and in more detail in the description. The invention also relates to a kit according to claim 18, comprising a 2K dispensing device comprising at least two cartridges, and to the use according to claim 19.

[0007] The present invention describes impression materials which, compared to the prior art, have a shortened setting time, in particular shorter time windows for the curing reaction, and preferably at the same time have a low temperature increase.

[0008] It has been found that for efficient network formation, i.e., a rapid curing reaction (tgo - ts) as the difference between setting time (tgo) and processing time (ts), a specific ratio of hydride- and vinyl-functional polysiloxanes must be established. To adjust the content of hydride-functional polysiloxanes, at least two specific polysiloxane compositions with different contents of polysiloxanes containing at least two Si-H groups are used to adjust the ratio of hydride-functional polysiloxanes. Furthermore, it has proven disadvantageous if monounsaturated compounds are present in the composition, such as low-molecular-weight species, for example, comprising monounsaturated compounds with H2C=CH-CH2, H2C=C(CH3)-CH2 groups, or monounsaturated compounds of formula I.It was found that the presence of monounsaturated compounds, which increase the reaction temperature and supposedly accelerate the addition crosslinking reaction, leads to competing reactions with the addition crosslinking reaction without accelerating curing. In this context, curing is correlated with the crosslinking reactions. According to the invention, the establishment of a specific ratio of hydride- and vinyl-functional siloxanes is crucial. For the additive crosslinking reaction of hydride-functional polysiloxanes, which are present in the base component, and vinyl-terminated polysiloxanes, which may be present in the base and catalyst components, these must be able to coordinate to a platinum catalyst.It has now been found that a specific ratio of at least two polysiloxane compositions, each with a defined molar content of Si-H groups, in a specific ratio to polysiloxanes with at least two terminal ethylene groups leads to accelerated curing (synonymous with curing or crosslinking) of the addition-crosslinkable polysiloxane-containing composition. It has further been found that while increasing the reaction temperature supposedly accelerates the addition reaction, the resulting competing reaction with the monounsaturated compound of formula I disproportionately delays the addition reaction, leading to unfavorable setting behavior and / or unfavorable time course of the curing reactions of the composition.

[0009] The defined time window of the curing reaction is characterized by the time difference tgo - ts. Here, ts corresponds to the processing time, i.e. the point in time up to which an almost stress-free deformation of the impression material is still possible. The time tgo corresponds to the setting time, i.e. the point in time at which a large part of the network has formed and only minimal deformation of the material is possible. Ideally, the time difference tgo - ts is as short as possible, as the impression can be removed from the patient's mouth quickly. The times are determined by measuring the viscosity of the mixed impression material at 30 °C using a rheometer. The setting time of the compositions was determined by measuring the viscosity as a function of time at 30 °C using a rheometer, as shown below.The total time was determined as the tgo value (setting time), at which 90% of the final viscosity of the complex viscosity was reached from the start of mixing. Another characteristic value is the ts value (processing time), at which 5% of the final viscosity of the complex viscosity is present. Up to this point in time, ts (processing window time), it is assumed that essentially no network formation has occurred in the composition (no curing). The difference t between the setting time tgo and the processing time ts is calculated using t = tgo - ts, defined here as the time window of the curing reaction, and corresponds to the transition time from the plastic to the elastic state of the material. The ratio between the processing time ts and the transition time t of the material is a measure of the so-called snap-set curing behavior of the material.ts corresponds to the time at which 5% of the final viscosity is reached, tgo corresponds to the time at which 90% of the final viscosity is reached. The measurement ends after 10 minutes. The defined time window for the curing reaction or crosslinking is defined as the time period from tgo minus ts. The time period before ts is reached is defined as the processing window time. The term "curable composition," which includes addition-curable polysiloxanes, is used synonymously with "crosslinkable composition."

[0010] Furthermore, it is preferred that the time ts (synonymous with t5) lasts at least 0.75 minutes, which in this case always corresponds to industrial minutes (industrial minutes, 60 minutes equals 100 industrial minutes, i.e. = hr + min / 60 + sec / 3600), in order to allow for the preparation of the mixture of base component and catalyst component, the application of the composition in the impression tray, the insertion of the impression tray in the patient's mouth, and optional adjustments. After correct placement of the impression tray in the patient's mouth, particularly rapid curing is desired. This rapid curing is specified in minutes by the time difference tgo minus ts.

[0011] According to the invention, a composition is provided which has a time window for a significantly faster additive curing or curing reaction of preferably less than 0.90 min for (tgo - ts) in industrial minutes (min.), particularly preferably less than 0.7 min. (tgo - ts) (min).

[0012] For the allyltrimethylsilane-containing compositions, curing reaction time windows (tgo - ts) of 0.94 minutes (allyltrimethylsilane in base paste) and 0.72 minutes (allyltrimethylsilane in catalyst paste) were determined. Compositions without the low-molecular-weight allylsilanes, in contrast, exhibited a significantly shorter curing time of less than 0.6 minutes and, depending on the Si-H content setting, of 0.33 minutes. In a particularly preferred embodiment, the composition is free of monofunctional and / or polyfunctional allylsilanes. The particularly preferred compositions that are free of monofunctional and / or polyfunctional allylsilanes can cure within a curing time of tgo - ts of less than 0.7 minutes, preferably less than 0.65 minutes, and more preferably less than or equal to 0.55 minutes.In a particularly preferred embodiment, curing can occur within tgo-ts of less than or equal to 0.4 minutes (industrial minutes). Compositions according to the modified reference examples exhibit a significant temperature increase of more than 10 °C. Such an extreme temperature increase will cause pain or be perceived as very unpleasant by the patient.

[0013] If polysiloxane compositions do not contain any allylsilanes, especially monofunctional and / or polyfunctional allylsilanes, unhindered additive curing of the hydride-functional polysiloxanes and vinyl-terminated polysiloxanes results. In the present invention, the curing time tgo - ts can be more than halved compared to allylsilane-containing silicone impression materials, with the same processing time. Furthermore, excessive heating of the materials, which could be perceived as unpleasant by the patient, is avoided.

[0014] The invention relates to a curable composition comprising addition-crosslinkable organofunctional polysiloxanes comprising, in particular selected from, i. addition-crosslinking polysiloxanes containing at least two terminal ethylene groups, and ii. polysiloxanes containing at least two Si-H groups, in particular polyhydrogensiloxanes, wherein the Si-H group-containing polysiloxanes comprise at least two polysiloxane compositions with different contents of Si-H groups, wherein a first polysiloxane composition (PS1) has a content of Si-H groups of 1 to 3.5 mmol / g and a second polysiloxane composition (PS2) has a content of Si-H groups of 3.8 mmol / g to 15 mmol / g, in particular the first and second and optionally further polysiloxane compositions are present as a mixture,wherein the first polysiloxane composition (PS1) contains Si-H groups and the second polysiloxane composition (PS2) contains Si-H groups in a weight ratio of 1:1.5 to 1:10, in particular in a weight ratio of 1:1.8 to 1:6, and wherein the molar ratio of Si-H groups of the polysiloxanes to ethylene groups of the polysiloxanes is from 4:1 to 10:1, and optionally comprising a hydrosilylation catalyst, and wherein the composition comprises essentially no monounsaturated compounds, in particular of the formula I.

[0015] Preferred polysiloxanes containing at least two Si-H groups have terminal Si-H groups and optionally pendant Si groups. Preferred polysiloxanes containing at least two terminal ethylene groups can optionally additionally comprise pendant ethylene groups. Polysiloxanes containing at least two terminal ethylene groups particularly preferably comprise terminal divinylpolysiloxanes, particularly preferably divinylpolydialkylsiloxanes, alkyl having 1 to 6 C atoms, particularly preferably divinylpolydimethylsiloxanes. Polysiloxanes containing Si-H groups or Si-H groups can also be synonymously referred to as polyhydrogensiloxanes.

[0016] Preferred hydrosilylation catalysts include hydrosilylation catalysts containing platinum, rhodium, and / or palladium. Another preferred embodiment comprises a composition whose maximum temperature increase (ΔT) upon curing is less than or equal to 7°C, preferably less than or equal to 6°C, particularly preferably less than or equal to 5°C, wherein the temperature increase is measured using a temperature sensor in the composition at intervals of 15 seconds from the first mixing to 10 minutes after the first mixing, with a temperature measurement being taken in particular every 30 seconds.

[0017] Furthermore, it is particularly preferred if, alternatively or cumulatively, (ii) the value ts in minutes (industrial minutes) of the complex viscosity of 5% of the complex viscosity corresponds to the value of the complex viscosity after 10 minutes after the start of mixing of the curable composition, is less than or equal to 1.7 minutes, preferably less than 1.6 minutes, particularly preferably less than or equal to 1.5 minutes, further preferably less than or equal to 1.4 minutes, and / or

[0018] (iii) the value tgo - ts as the difference between the time tgo at which 90% of the complex viscosity of the complex viscosity value is reached after 10 minutes and the time ts at which 5% of the complex viscosity of the complex viscosity value is reached after 10 minutes, is less than or equal to 1 minute, in particular less than or equal to 0.8 minutes, preferably less than or equal to 0.7 minutes, particularly preferably less than or equal to 0.6 minutes. Further preferably less than or equal to 0.5 minutes with a deviation of + / - 20%, wherein the temperature increase is preferably less than or equal to 6 °C, preferably less than or equal to 5 °C.

[0019] The processing time ts in minutes, i.e. the point in time up to which an almost stress-free deformation of the impression material is still possible, is preferably less than or equal to 1.8 minutes (industrial minutes), preferably less than or equal to 1.6 minutes, particularly preferably less than or equal to 1.5 minutes and preferably greater than or equal to 1 minute, wherein alternatively or additionally the time window of the curing reaction (tgo - ts) in minutes is less than or equal to 0.9 minutes, preferably less than or equal to 0.85 minutes, particularly preferably less than or equal to 0.7 minutes, wherein optionally at the same time the temperature increase is less than 7 °C. It is further preferred if the processing time ts in minutes (industrial minutes) is greater than or equal to 0.8 minutes, in particular greater than or equal to 0.9 minutes, and less than or equal to 2 minutes, preferably less than or equal to 1.5 minutes.

[0020] Without being bound to theory, it is assumed that the rapid setting combined with a good processing time results from a PS1 / PS2 weight ratio (PS1 = crosslinker with SiH 1.3 to 2.5 mmol / g and PS2 = crosslinker with SiH 4 to 8 mmol / g) of 1:1.8 to 1:6 and a molar SiH group to vinyl group ratio of 4.5 to 9.3. The compositions according to the invention correspond to a free-flowing corrective impression material, but in principle, transfer to all consistencies (Type 3 - Type 0 according to DIN EN ISO 4823:2021, DIN EN ISO 4823:2021-06) is possible.

[0021] According to a preferred embodiment, the addition-crosslinking polysiloxanes containing at least two terminal ethylene groups comprise polydialkylsiloxanes, polydialkylsiloxane ethers or mixtures thereof, in particular with alkyl each independently having 1 to 16 C atoms, preferably alkyl having 1 to 4 C atoms, particularly preferably methyl groups.

[0022] Preferably, the composition according to a preferred embodiment comprises substantially no monounsaturated compound(s), in particular of formula I. Furthermore, the compositions according to a preferred embodiment comprise substantially no monounsaturated compound of formula I

[0023] R 2 R 3 C=CR 1 -A-SiR3(I) with

[0024] R is each independently selected from H, monovalent alkyl group having 1 to 22 C atoms, aryl group having 16 to 12 C atoms, O-SiR 4 3-group, where

[0025] R optionally comprises heteroatoms, with the proviso that R is not an alkoxy group or arylalkoxy group,

[0026] R 1 , R 2 , R 3 are each independently selected from H, monovalent alkyl group having 1 to 22 C atoms, aryl group having 6 to 12 C atoms and optionally each independently comprise heteroatoms,

[0027] R 4 a monovalent alkyl group having 1 to 22 C atoms or aryl group having 6 to 12 C atoms, optionally containing two or three R 4 Residues in O-SiR 4 3can form a cyclic or polycyclic structure,

[0028] A is a bivalent linear, branched or cyclic hydrocarbon group having 1 to 12 C atoms, optionally comprising an aromatic having at least one methylene group which is directly covalently bonded to the aromatic, optionally comprising

[0029] -O atoms, preferably A is methylene, ethylene, propylene, butylene, hexylene, octylene, nonylene, or decylene. A composition containing no monounsaturated compound(s), in particular of formula I, is understood to mean compositions having a maximum content of 0.001 wt.% in the total composition of 100 wt.%, with the content preferably being 0%.

[0030] Verbindungen der Formel I umfassen: H2C=CH-CH2Si(CH3)3CAS: [762-72- 1], H2C=CH-(CH2)2Si(CH3)3, H2C=CH-(CH2)3Si(CH3)3, H2C=CH-(CH2)4Si(CH3)3, H2C=CH- (CH2)8Si(CH3)3, H2C=CH-CH2Si(i-C3H7)3CAS: [24400-84-8],

[0031] H2C=CH-(CH2)2Si(i-C3H7)3, H2C=CH-(CH2)3Si(i-C3H7)3, H2C=CH-(CH2)4Si(i-C3H7)3, H2C=CH- (CH2)2Si(CH3)2(t-C4H9), H2C=CH-(CH2)3Si(CH3)2(t-C4H9),

[0032] H2C=CH-(CH2)4Si(CH3)2(t-C4Hg), H2C=CH-(CH2)8Si(CH3)2(t-C4H9),

[0033] H2C=CH-CH2Si(C2H5)3, H2C=CH-(CH2)2Si(C2H5)3, H2C=CH-(CH2)3Si(C2H5)3, H2C=CH- (CH2)4Si(C2H5)3, H2C=CH-(CH2)8Si(C2H5)3, H2C=CH-CH2Si(CH3)2(n-Ci8H 37 ), H2C=CH- (CH2)2Si(CH3)2(n-Ci8H 37 ), H2C=CH-(CH2)3Si(CH3)2(n-Ci8H 37 ), H2C=CH-(CH2)4Si(CH3)2(n- CI8H 37 ), H2C=CH-(CH2)8Si(CH3)2(n-Ci8H 37 ),

[0034] H2C=CH-CH2Si(CH3)2(C6H5), H2C=CH-(CH2)2Si(CH3)2(C6H5),

[0035] H2C=CH-(CH2)3- Si(CH3)2(C6H5), H2C=CH-(CH2)4Si(CH3)2(C6H5),

[0036] H2C=CH-(CH2)8Si(CH3)2(C6H5), H2C=CH-CH2-O-Si(CH3)3, H2C=CH-CH2-O-Si(C2H5)3,

[0037] H2C=CH-CH2-O-Si(i-C3H7)3, H2C=CH-CH2-O-Si(CH3)2(t-C4H9),

[0038] H2C=CH-CH2-O-Si(CH3)2(n-Ci8H 37 ), H2C=CH-CH2-O-Si(CH3)2(C6H5),

[0039] H2C=CH-CH2Si(CH3)2-O-Si(CH3)3, H2C=CH-(CH2)2Si(CH3)2-O-Si(CH3)3,

[0040] H2C=CH-(CH2)3Si(CH3)2-O-Si(CH3)3H2C=CH-(CH2)4Si(CH3)2-O-Si(CH3)3,

[0041] H2C=CH-(CH2)8Si(CH3)2-O-Si(CH3)3, H2C=CH-CH2Si(CH3)(-O-Si(CH3)3)2,

[0042] H2C=CH-(CH2)2Si(CH3)(-O-Si(CH3)3)2, H2C=CH-(CH2)3Si(CH3)(-O-Si(CH3)3)2, H2C=CH- (CH2)4Si(CH3)(-O-Si(CH3)3)2, H2C=CH-(CH2)8Si(CH3)(-O-Si(CH3)3)2, H2C=CH-CH2Si(-O- Si(CH3)3)3, H2C=CH-(CH2)2Si(-O-Si(CH3)3)3,

[0043] H2C=CH-(CH2)3Si(-O-Si(CH3)3)3, H2C=CH-(CH2)4Si(-O-Si(CH3)3)3,

[0044] H2C=CH-(CH2)8Si(-O-Si(CH3)3)3, H2C=CH-CH2Si(OCH3)3,

[0045] <h2 style=";text-align:left;direction:ltr">H2C=CH-(CH2)2Si(OCH3)3, H2C=CH-(CH2)3Si(OCH3)3, H2C=CH-(CH2)4Si(OCH3)3, H2C=CH- (CH2)8Si(OCH3)3, H2C=CH-CH2Si(OC2H5)3, H2C=CH-(CH2)2Si(OC2H5)3, H2C=CH-(CH2)3Si(OC2H5)3, H2C=CH-(CH2)4Si(OC2H5)3, H2C=CH-(CH2)8Si(OC2H5)3, H2C=CH-CH2Si(C6H5)3CAS: [18752-21- 1], H2C=CH-(CH2)2Si(C6H5)3,<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr">

[0046] <h2 style=";text-align:left;direction:ltr"> H2C=CH-(CH2)3Si(C6H5)3, H2C=CH-(CH2)4Si(C6H5)3, H2C=CH-(CH2)8Si(C6H5)3, H2C=C(CH3)- CH2Si(CH3)3CAS: [18292-38- 1], H2C=CH-CH2Si(p-C6H)<h2 style=";text-align:left;direction:ltr"> 40 <h2 style=";text-align:left;direction:ltr"> CH3) CAS: [68469-60-3], H2C=CH- CH2Si(CH3)2H, H2C=CH-(CH2)2Si(CH3)2H,<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr">

[0047] <h2 style=";text-align:left;direction:ltr"> H2C=CH-(CH2)3Si(CH3)2H, H2C=CH-(CH2)4Si(CH3)2H, H2C=CH-(CH2)8Si(CH3)2H, and Mischungen dieser.<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr">

[0048] Allylsilanes, especially monofunctional and / or multifunctional allylsilanes, are considered organofunctional silicon compounds that do not contain Si-O-Si fragments and are therefore not siloxanes. The compositions most preferably do not contain monofunctional allylsilanes. Alternatively, the compositions may be free of di-, tri-, or tetrafunctional allylsilanes, or free of di-, tri-, and tetrafunctional allylsilanes.

[0049] A composition which contains less than or equal to 0.035% by weight of a monounsaturated compound, in particular one or more compound(s) of the formula I and / or no allylsilanes in a total composition of the curable composition of 100% by weight, is considered to contain essentially no monounsaturated compound, preferably no unsaturated compound of the formula I, and / or no allylsilanes, preferably less than or equal to 0.025% by weight, more preferably less than or equal to 0.001% by weight. Alternatively, a composition containing a base component and / or catalyst component which each independently contains less than or equal to 0.025% by weight, preferably less than or equal to 0.001% by weight, based on the respective total composition of 100% by weight, is considered to contain essentially no monounsaturated compound, in particular of the formula I.Preferred monounsaturated compounds of formula I which are not present in the composition have a molecular weight of less than 500 g / mol, preferably less than 250 g / mol.

[0050] Furthermore, a preferred composition may not comprise any tetraallylsilane content. Preferably, a composition may comprise no tetraallylsilane content or a maximum of 0.001 to 0.25 wt. %, in particular 0.001 to 0.15 wt. %, preferably 0.001 to 0.1 wt. %, of tetraallylsilane, based on the total composition of the curable composition of 100 wt. %. In a particularly preferred alternative, the curable composition does not comprise any tetraallylsilane. It has been found that a certain amount of tetraallylsilane can be advantageously added to the composition to extend the processing time to a certain extent, in particular without adversely affecting the additive curing in the time window tgo - ts, so that, taken together, a good processing time of less than 2 minutes and subsequent rapid curing of less than 1 minute can be achieved.

[0051] The significant advantage of the invention is thus that the inventive ratio of at least two polysiloxanes containing terminal ethylene groups and at least two polysiloxanes containing Si-H groups allows for very rapid additive curing within a time window. The time window can be adjusted to longer processing times by adding tetraallylsilane, while maintaining rapid curing, so that the total time from mixing to reaching 90% of the complex viscosity at 30°C can be less than 3 minutes. Furthermore, it is particularly preferred if a composition comprises at least one surfactant comprising a polyether, polyether-functionalized siloxane oligomer, fatty alcohol and / or fluorosurfactant or mixtures of the aforementioned surfactants. Preferred surfactants can optionally comprise at least one nonionic or ionic fluorosurfactant containing at least one fluoroalkyl group.Particularly preferably, a composition comprises at least one surfactant comprising a polyether and / or at least one polyether-functionalized siloxane oligomer or mixtures of the aforementioned surfactants. Preferred surfactants comprise polyether-functional siloxane surfactants and optionally a polyether, such as allyloxypolyethylene glycol alkyl ether, preferably allyloxypolyethylene glycol methyl ether, to adjust the hydrophilicity of the composition. Preferred surfactants comprise polyether-functionalized siloxane oligomers having at least one alkylsiloxane group and optionally a polyether. Particularly preferably, the additional surfactant comprises at least one polyether-alkylene-functionalized siloxane oligomer having at least one alkylsiloxane group. By definition, surfactants do not contain SiH and / or ethylene groups.

[0052] Surfactants are typically added to addition-curing impression materials to increase their hydrophilicity and thus facilitate their flow onto moist surfaces. In addition to conventional non-ionic surfactants, partially fluorinated and / or perfluorinated surfactants are also used in dental impression materials, sometimes in combination with conventional surfactants.

[0053] The content of surfactant(s) in the composition may be from 0.1 to 10 wt.%, preferably from 0.1 to 7.5 wt.%, particularly preferably from 0.1 to 5 wt.%, further preferably from 1 to 3 wt.%, the total composition of the curable composition being 100 wt.%.

[0054] The invention also provides a composition comprising addition-crosslinking polysiloxanes containing at least two terminal ethylene groups and having an ethylene group content of 0.01 mmol / g to 10 mmol / g, particularly vinyl groups. In particular, the polysiloxanes containing at least two terminal ethylene groups comprise a mixture of polysiloxanes (EP1) containing terminal ethylene groups from 0.01 to 0.07 mmol / g of vinyl groups and polysiloxanes (EP2) containing terminal ethylene groups from 0.1 to 0.5 mmol / g of vinyl groups.Preferably, the terminal ethylene group-containing polysiloxanes (EP1) comprise polysiloxanes having a vinyl group content of 0.01 to 0.07 mmol / g and a viscosity of 100 mPas to 2000 mPas (viscosity determination method: DIN 53015 Höppler, vinyl group content via FTIR spectroscopy using a calibration curve) and the terminal ethylene group-containing polysiloxanes (EP2) having a vinyl group content of 0.1 to 0.5 mmol / g have a viscosity of 5000 to 20000 mPas. The weight ratio of EP1 to EP2 is preferably in the range from 10:1 to 1:10, preferably from 5:1 to 1:2. It is further preferred if in the base component the weight ratio of EP1:EP2 is from 5:1 to 2:1 and / or in the catalyst component the weight ratio of EP1:EP2 is from 2:1 to 1:10, preferably from 1.5:1 to 1:2.

[0055] According to a particularly preferred embodiment, a curable composition comprises a first polysiloxane composition (PS1) having a content of Si-H groups of 1 to 3.0 mmol / g, preferably a content of Si-H groups of 1.3 to 2.5 mmol / g, more preferably a content of Si-H groups of 1.4 to 2.5 mmol / g. Likewise, a preferred composition can preferably simultaneously comprise a second polysiloxane composition (PS2) having a content of Si-H groups of 3.9 mmol / g to 10 mmol / g, preferably a content of Si-H groups of 4.0 to 5.0 mmol / g, in particular 4.1 to 5.0 mmol / g, alternatively preferably a content of Si-H groups of 4.0 to 8.0 mmol / g, in particular 4.1 to 8.0 mmol / g.

[0056] Furthermore, it is particularly preferred if in the curable composition the molar ratio of Si-H groups of the polysiloxanes to ethylene groups of the polysiloxanes is from 3.5:1 to 10:1, in particular from 6:1 to 10:1.

[0057] Particularly preferably, in the curable composition or in a mixture of base component and catalyst component, in particular in a ratio of 5:1 to 1:5, preferably of 1:1 to 2:1 to 1:2, particularly preferably of 1:1, there is a molar ratio of Si-H groups of the polysiloxanes to ethylene groups of the polysiloxanes of 1:1.8 to 1:6 with a first polysiloxane composition (PS1) having a content of Si-H groups of 1.3 to 2.5 mmol / g and a second polysiloxane composition (PS2) having a content of Si-H groups of 4 mmol / g to 8 mmol / g, and optionally wherein the ratio of terminal ethylene groups of the base component to terminal ethylene groups in the catalyst component is in a molar ratio of 1: 1.1 to 1:10, preferably the molar ratio is from 1:1.2 to 1:10, particularly preferably from 1:1.3 to 1:10, further preferably from 1:1.4 to 1:2.

[0058] According to a preferred embodiment, the first and second polysiloxane compositions are present in the composition as a mixture, and wherein the first polysiloxane composition (PS1) and the second polysiloxane composition (PS2) are present in a weight ratio of 1:1.6 to 1:10, or of 1:3 to 1:10, in particular in a weight ratio of 1:4 to 1:6. Furthermore, it is preferred if PS1 and PS2 are present in a weight ratio of 1:1.7 to 1:10, in particular in a weight ratio of 1:1.7 to 1:6, preferably of 1:1.8 to 1:2.3. According to a very particularly preferred embodiment, the first and second polysiloxane compositions are present as a mixture, the first polysiloxane composition (PS1) and the second polysiloxane composition (PS2) being present in a weight ratio of 1:1.5 to 1:2.2, in particular in a weight ratio of 1:1.5 to 1:2.

[0059] According to a further preferred embodiment, the curable composition is obtainable, is prepared or is obtained by mixing two components to obtain an addition-crosslinking curable composition, wherein the two components comprise, in particular are selected from: a) base component comprising addition-crosslinking polysiloxanes containing at least two terminal ethylene groups and polydialkylsiloxanes containing at least two Si-H groups, in particular polydialkylsiloxanes containing at least two terminal ethylene groups and polydialkylsiloxanes containing at least two Si-H groups, and b) catalyst component comprising a platinum, rhodium and / or palladium-containing hydrosilylation catalyst and optionally comprising addition-crosslinking polysiloxanes containing terminal ethylene groups and optionally polysiloxanes containing Si-H groups, in particular polydialkylsiloxanes containing terminal ethylene groups,and optionally, wherein the base component and / or the catalyst component may each independently comprise,

[0060] - optionally inorganic fillers, organic particulate polymers, in particular with a particle size of 10 nm to 75 micrometers, and

[0061] - optional pigments comprising organic or inorganic pigments.

[0062] It is preferred in each case that the base component and / or the catalyst component each independently contains at least one nonionic or ionic, at least one polyether and / or one polyether-functionalized siloxane oligomer and optionally one or mixtures of the aforementioned surfactants.

[0063] According to an alternative embodiment, a curable composition comprises addition-crosslinkable organofunctional polysiloxanes comprising, in particular selected from, i. addition-crosslinking polysiloxanes containing at least two terminal ethylene groups, in particular with from 0.01 to 10 mmol / g of terminal ethylene groups, preferably from 0.025 mmol / g to 5 mmol / g, particularly preferably from 0.025 mmol / g to 1 mmol / g, and ii.polysiloxanes containing at least two Si-H groups, in particular polyhydrogensiloxane, wherein the polysiloxanes containing Si-H groups comprise at least two polysiloxane compositions with different contents of Si-H groups, wherein a first polysiloxane composition (PS1) has a content of Si-H groups of 1 to 3.0 mmol / g and a second polysiloxane composition (PS2) has a content of Si-H groups of 3.9 mmol / g to 15 mmol / g, in particular the first and second and optionally further polysiloxane compositions are present as a mixture, wherein the first polysiloxane composition (PS1) has a content of Si-H groups and the second polysiloxane composition (PS2) has a content of Si-H groups in a weight ratio of 1:1.8 to 1:6, and wherein the molar ratio of Si-H groups of the polysiloxanes to ethylene groups of the polysiloxanes is from 4 : 1 to 10 : 1.

[0064] Furthermore, a composition is preferred in which the polydialkylsiloxanes containing at least two terminal ethylene groups can be selected from vinyl-terminated polydialkylsiloxanes and vinyl-terminated polyether-functional polydialkylsiloxanes, and / or the polydialkylsiloxanes containing at least two Si-H groups can be selected from polydialkylsiloxanes and polyether-functional polydialkylsiloxanes, wherein these can contain terminal Si-H groups and optionally -Si(CHs)H groups in the polysiloxane backbone.

[0065] Preferred polysiloxanes include polydialkylsiloxanes with alkyl each independently having 1 to 16 C atoms, in particular methyl groups.

[0066] According to a further preferred embodiment, the vinyl-terminated polydialkylsiloxanes and vinyl-terminated polyether-functional polydialkylsiloxanes can be selected from vinyl-terminated polydimethylsiloxanes and vinyl-terminated polyether-functional polydimethylsiloxanes. The Si-H group-containing polydialkylsiloxanes can preferably be selected from polydimethylsiloxanes and polyether-functional polydimethylsiloxanes that contain terminal Si-H groups and, optionally, -Si(CHs)H groups in the polysiloxane backbone. Furthermore, the vinyl-terminated polysiloxanes preferably comprise vinyl-terminated polydialkylsiloxanes and vinyl-terminated polyether-functional polydialkylsiloxanes having an average molecular weight (mass average, weight average) Mw in the range from 31,000 g / mol to 124,000 g / mol, preferably the number average Mn is in the range from 22,000 g / mol to 89,000 g / mol.Likewise, it is preferred if the polydialkylsiloxanes containing Si-H groups are selected from polydimethylsiloxanes and polyether-functional polydimethylsiloxanes, each independently having terminal Si-H groups and optionally in the polysiloxane backbone having -Si(CH3)H groups, in particular having an average molecular weight (mass average, weight average) Mw in the range from 500 g / mol to 19,000 g / mol, and preferably the number average Mn is in the range from 500 g / mol to 14,000 g / mol.

[0067] The polydialkylsiloxanes containing at least two Si-H groups are preferably selected from polydialkylsiloxanes and polyether-functional polydialkylsiloxanes containing terminal Si-H groups and optionally in the polysiloxane backbone -Si(CHs)H groups and with a content of Si-H and optionally in the polysiloxane backbone -Si(CHs)H groups of

[0068] 4 to 8 mmol / g, in particular from 4.05 mmol / g to 8 mmol / g. It may further be preferred that the polydialkylsiloxanes containing Si-H groups are selected from polydialkylsiloxanes and polyether-functional polydialkylsiloxanes, each independently containing terminal Si-H groups and optionally in the polysiloxane backbone containing -Si(CHs)H groups, which have a viscosity of 10 to 500 mPa s.

[0069] The polydialkylsiloxanes containing terminal ethylene groups can preferably be selected from vinyl-terminated polydialkylsiloxanes and vinyl-terminated polyether-functional polydialkylsiloxanes, with a content of vinyl groups in the range from 0.02 mmol / g to 2.0 mmol / g, preferably from 0.02 to 1.0 mmol / g.

[0070] According to an alternative embodiment, a composition is preferred which is obtainable or obtained by mixing an i) base component and ii) catalyst component, wherein i) the base component comprises

[0071] 30 to 50% by weight, in particular 35 to 45% by weight, of polydialkylsiloxanes containing at least two terminal ethylene groups,

[0072] 15 to 64% by weight, in particular 30 to 50% by weight, of inorganic fillers,

[0073] 5 to 30 wt.%, in particular 7 to 25 wt.%, of polydialkylsiloxanes containing at least two Si-H groups, 1.0 to 15 wt.%, in particular 1 to 10 wt.%, of at least one surfactant, in particular at least one polyether and / or at least one polyether-functionalized siloxane oligomer, in particular the polyether-functionalized siloxane oligomer has at least one alkylsiloxane group, or mixtures of these surfactants, and wherein the total of the base component is 100 wt.%, and ii) the catalyst component comprises

[0074] 20 to 80 wt.%, in particular 35 to 65 wt.%, of polydialkylsiloxanes containing at least two terminal ethylene groups,

[0075] 5 to 70 wt.%, in particular 35 to 65 wt.%, inorganic fillers,

[0076] 0.001 to 5.0 wt.% platinum, rhodium or palladium-containing hydrosilylation catalyst,

[0077] 0 to 15 wt.% of at least one surfactant, in particular 1.0 to 15 wt.% of at least one surfactant, in particular at least one polyether and / or at least one polyether-functionalized siloxane oligomer, in particular the polyether-functionalized siloxane oligomer has at least one alkylsiloxane group, or mixtures of these surfactants, and

[0078] 0 to 10 wt.% organic or inorganic pigments and / or structuring agents, the total sum of the catalyst components being 100 wt.%.

[0079] According to a preferred alternative, the base components and the catalyst component are mixed in a weight ratio of 10:1 to 1:10, in particular in a ratio of 5:1 to 1:5, preferably of 2:1 to 1:2.

[0080] Furthermore, it is preferred if the composition is obtainable or is obtained by mixing an i) base component and ii) catalyst component, wherein i) the base component comprises 30 to 50 wt.% of polydialkylsiloxanes containing at least two terminal ethylene groups, and ii) the catalyst component comprises 20 to 80 wt.% of polydialkylsiloxanes containing at least two terminal ethylene groups, and wherein the ratio of terminal ethylene groups of the base component to terminal ethylene groups of the catalyst component is in a molar ratio of 1:1.1 to 1:10, preferably the molar ratio is from 1:1.2 to 1:10, particularly preferably from 1:1.3 to 1:10, further preferably from 1:1.4 to 1:2. Preferred curable compositions comprise a i) base component and a ii) catalyst component or are optionally available by mixing a i) base component and ii) catalyst component, wherein i) comprises

[0081] 30 to 50% by weight, in particular 20 to 39% by weight, of polydialkylsiloxanes containing terminal ethylene groups,

[0082] 15 to 64% by weight, in particular 36 to 63% by weight, of inorganic fillers,

[0083] 5 to 30 wt.%, in particular 5 to 21 wt.%, of polydialkylsiloxanes containing Si-H groups,

[0084] 1.0 to 15 wt.%, in particular 1 to 10 wt.%, of at least surfactant and optionally at least one further surfactant comprising at least one polyether and / or at least one polyether-functionalized siloxane oligomer, particularly preferably from 4 to 8 wt.% of at least one polyether and / or at least one polyether-functionalized siloxane oligomer, in particular the polyether-functionalized siloxane oligomer has at least one alkylsiloxane group, or mixtures of these surfactants, preferably the further surfactant is at least one polyether-functionalized siloxane oligomer, and 0 to

[0085] 10 wt.%, in particular 0.001 to 0.5 wt.%, palladium-containing composition, and 0 to 10 wt.% organic or inorganic pigments and / or structuring agents, wherein the total sum of the components in the base component is 100 wt.%, and ii) comprises 20 to 80 wt.%, in particular 30 to 80 wt.%, polydialkylsiloxanes containing terminal ethylene groups, particularly preferably 36 to 61 wt.%,

[0086] 5 to 70 wt.%, in particular 36 to 61 wt.%, inorganic fillers,

[0087] 0.001 to 5.0% by weight, in particular 0.2 to 1.0% by weight, of a platinum, rhodium or palladium-containing hydrosilylation catalyst, in particular a platinum-containing hydrosilylation catalyst, preferably a Karstedt catalyst,

[0088] 1.0 to 15% by weight, in particular 1 to 10% by weight, of at least one surfactant and optionally at least one further surfactant comprising at least one polyether and / or at least one polyether-functionalized siloxane oligomer, in particular the polyether-functionalized siloxane oligomer has at least one alkylsiloxane group, or mixtures of these surfactants, preferably the further surfactant is at least one polyether-functionalized siloxane oligomer,

[0089] 0 to 10 wt.% organic or inorganic pigments and / or structuring agents, wherein the total sum of the components in the catalyst component is 100 wt.%, wherein the total content of the at least one surfactant and optionally of the at least one further surfactant comprising at least one polyether and / or at least one polyether-functionalized siloxane oligomer or a mixture of the aforementioned surfactants in the composition is from 2.0 to 20 wt.%. According to a further alternative, the invention relates to a kit comprising a 2K dispensing device comprising at least two cartridges, wherein the i) base component is present in one cartridge and the ii) catalyst components are present in the second cartridge. The kit can further comprise at least one removable and attachable static mixer.

[0090] Preferably, the at least one further surfactant is selected from polyether and polyether-functionalized siloxane oligomers, wherein the siloxane oligomer contains at least one alkylsiloxane group, in particular the polyethers and / or the polyether groups of the polyether-functionalized siloxane oligomers are selected from polyalkylene oxide groups, in particular the polyalkylene oxide groups are selected from polyethylene oxide groups comprising methoxy-polyethylene oxide-alkylene groups, ethoxy-polyethylene oxide-alkylene groups, methoxy-ethylene oxide-alkylene groups, polyethylene oxide-alkylene groups.

[0091] More preferably, the at least one further surfactant comprises or is selected from polyethers and polyether-functionalized siloxane oligomers, wherein the siloxane oligomer contains at least one alkyltrisiloxane group, preferably a polyalkylene oxide-functionalized heptamethyltrisiloxane, preferably a polyethylene oxide-alkylene-functionalized heptamethyltrisiloxane, particularly preferably 3-(2-methoxyethoxy)propylmethylbis(trimethylsilyoxy)silane.

[0092] The surfactant is particularly preferably selected from polyethers and polyether-functionalized siloxane oligomers, wherein the siloxane oligomer contains at least one alkylsiloxane group, in particular the polyethers and / or the polyether groups of the polyether-functionalized siloxane oligomers are selected from polyalkylene oxides.

[0093] Preferably, the polyalkylene oxide groups of the polyether-functionalized siloxane oligomers are selected from polyethylene oxide groups, methoxy-polyethylene oxide-alkylene groups, ethoxy-polyethylene oxide-alkylene groups, methoxy-ethoxy-alkylene groups,

[0094] Polyethylene oxide-alkylene groups, preferred is a polyalkylene oxide-functionalized alkyltrisiloxane, preferably a polyalkylene oxide-functionalized heptamethyltrisiloxane, particularly preferred is polyalkylene oxide-alkylene-functionalized heptamethyltrisiloxane. The viscosity of the additional surfactant is preferably 15 to 24.1 mPas. Preferred additional surfactants include: 3-(2-methoxyethoxy)propylmethylbis(trimethylsilyoxy)silane. Polyethers include a- and / or o-polyethers of alkenyl polyethers, alkynyl polyethers, hydroxy polyethers, aryloxy-, arylalkyloxy-, and / or alkoxy-terminated polyethers. Preferred polyethers include α-alkenylene-o-alkyl polyethers containing C1 to C8 alkenylene and C1 to C4 alkyl, preferably allyl polyethylene glycol methyl ether (CAS 27252-80-8) and / or α,o-alkyl polyethers containing C1 to C4 alkyl. The additional surfactant can preferably be present as a mixture of polyethers and polyether-functionalized siloxane oligomers.

[0095] Polyethers according to the present invention can be present as surfactant comprising C2 to C4 alkylene oxides or as polyether-functional polydialkylsiloxanes containing terminal ethylene groups.

[0096] The polyether-functional polydialkylsiloxanes containing terminal ethylene groups are preferably selected from vinyl-terminated polyether-functional polydialkylsiloxanes comprising C2 to C4 alkylene oxides. Suitable polyols for preparing the polyethers are, for example, the reaction products of ethylene glycol, propylene glycol, butanediol, or hexanediol isomers with one or more of the following alkylene oxides: ethylene oxide, propylene oxide, or butylene oxides, such as tetrahydrofuran. Furthermore, polyethers can also be reaction products of polyfunctional alcohols such as glycerol, trimethylolethane or trimethylolpropane, pentaerythritol, or sugar alcohols, or mixtures of two or more thereof, with the aforementioned alkylene oxides, which are suitable for forming the polyether polyols.

[0097] Suitable platinum-, rhodium-, or palladium-containing hydrosilylation catalysts are understood to be platinum-, rhodium-, or palladium-containing catalysts or their precatalysts that can be dissolved in the siloxanes and preferably in the components. Thus, catalysts that do not form a disperse phase in the other compounds present in the components are preferred. Platinum complexes comprising ethylenic siloxane compounds, preferably divinyldisiloxanes, are preferred. Typical precatalysts are hexachloroplatinic acid dissolved in isopropanol (Speier catalyst) and Karstedt catalysts (H2PtCle and divinyldisiloxanes such as (CH2=CH)Me2Si-O-SiMe2(CH=CH2)). Karstedt catalysts can contain binuclear platinum(O) complexes.Equally preferred hydrosilylation catalysts include [1,3-bis(cyclohexyl)imidazol-2-ylidene][1,3-divinyl I-1,1,3,3-tetramethyldisiloxane]platinum(O)(Icy)Pt(vs); [1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene][1,3-divinyl I-1,1,3,3-tetramethyldisiloxane]platinum(O), (Ipr)Pt(vs). Alternatively, the polydimethylsiloxanes can be substituted by 1 to 10 mol% of the methyl groups in the siloxane backbone by alkyl groups having C2 to C16, in particular C2 to C8, and / or phenyl groups. Alternatively, allyl-terminated polydialkylsiloxanes or allyl-terminated polyether-functional polydialkylsiloxanes can be used.

[0098] Furthermore, compositions are preferred in which the vinyl-terminated polydialkylsiloxanes and vinyl-terminated polyether-functional polydialkylsiloxanes have an average molecular weight (mass average, weight average) Mw in the range from 31,000 g / mol to 124,000 g / mol, preferably the number average Mn is in the range from 22,000 g / mol to 89,000 g / mol, and / or the Si-H group-containing polydialkylsiloxanes are preferably selected from polydimethylsiloxanes and polyether-functional polydimethylsiloxanes with terminal Si-H groups and optionally with groups containing -Si(CHs)H- in the polysiloxane backbone, in particular with an average molecular weight (mass average, weight average) Mw in the range from 500 g / mol to 19,000 g / mol, and preferably the number average Mn is in the range from 500 g / mol to 14000 g / mol. The determination of Mw and Mn can be performed using gel permeation chromatography (SDB copolymer with toluene eluent).

[0099] Likewise preferred are compositions which comprise polydialkylsiloxanes containing terminal ethylene groups which are selected from vinyl-terminated polydialkylsiloxanes and vinyl-terminated polyether-functional polydialkylsiloxanes which have a viscosity of 100 to 100,000 mPa s, and / or in which the polydialkylsiloxanes containing Si-H groups are selected from polydialkylsiloxanes and polyether-functional polydialkylsiloxanes which contain terminal Si-H groups and optionally Si(CHs)H groups in the polysiloxane backbone and have a viscosity of 10 to 500 mPa s, in particular of 20 to 50 mPa s (DIN 53015 Höppler ball 3) and optionally of 200 to 340 mPa s (DIN 53015 Höppler ball 4). The viscosity is generally determined using (DIN 53015 Höppler), whereby for the polydialkylsiloxanes containing ethylene groups the viscosity is determined using rotational viscosity cone (4740 mm) / plate BU-Q 30.027) U0.2 / U1 : DIN 53015 Höppler ball 5 can be done.

[0100] Likewise, curable composition, base and / or catalyst component comprising polydialkylsiloxanes containing Si-H groups of a first polysiloxane composition (PS1) are preferred, which comprise the terminal Si-H groups and optionally -Si(CH3)H groups contained in the polysiloxane backbone, wherein the content of Si-H and optionally in the polysiloxane backbone of -Si(CHs)H groups is from 1 to 3.5 mmol / g, preferably the content is from 1 to 2 mmol / g. Also preferred are compositions, base and / or catalyst components comprising polydialkylsiloxanes containing Si-H groups of a second polysiloxane composition (PS2), which comprise the terminal Si-H groups and optionally -Si(CH3)H groups contained in the polysiloxane backbone, wherein the content of Si-H and optionally in the polysiloxane backbone of -Si(CHs)H groups is from 3.8 to 15 mmol / g, preferably the content is from 4 to 8, in particular 4.05 to 8 mmol / g.

[0101] Rheological aids such as Aerosils or the like can be used as structuring agents. Palladium-containing compositions can be added to the curable compositions as hydrogen scavengers. Inorganic fillers or organic particulate polymers that can be used include silicon dioxide, fumed silica, precipitated silica, quartz, and kaolin, with the inorganic fillers preferably being hydrophobicized. Other surfactants that can be used include fatty alcohols, such as ethoxylated fatty alcohols, particularly C11 to C14 alcohols.

[0102] According to a preferred embodiment, the base component and the catalyst component can be mixed in a weight ratio of about 1:1 to 10:1, preferably about 1:1 or about 5:1 or about 4:1 or about 10:1. Particularly preferably in a weight ratio of 2:1 to 1:2, further preferably 1:1 with a deviation of + / - 15 wt.%.

[0103] The invention also relates to the use of the composition for making impressions in the medical, dental and / or veterinary field, for making impressions in the field of botany, for making impressions in the marine and aquatic field, for making impressions of surfaces of articles, for making impressions of design, art or craft objects, as a dental impression material, as an impression material for human, veterinary or marine soft (tissue) and / or hard structures (bones, shells, coral), such as ear impressions, podiatry, forensic science, for making impressions of electronic components, for making impressions of objects whose surfaces are wetted with aqueous compositions or whose surfaces are wetted with water and / or for printing three-dimensional structures, in particular in the semiconductor field.

[0104] The compositions according to the invention are suitable as impression materials in which high levels of detail accuracy are required. Impression materials, in particular dental impression materials, include precision impression materials, situation impression materials, bite registration materials, duplication materials (usable for duplicating master models such as all-ceramic restorations, inlays, onlays, cantilevers), as well as modeling materials such as those used for gingival reconstruction.

[0105] The following are exemplary embodiments intended to explain the invention without limiting it to the specific examples.

[0106] Figure 1 shows: Complex viscosity (r|*(ts), *(tgo) over 10 minutes for modified Reference Example 1, HAAKE RheoStress 1, rotational rheometer, oscillation mode, 30 °C

[0107] The base pastes (base component) and catalyst pastes (catalyst component) were each homogenized separately in a planetary mixer. For the subsequent experiments, 60 g batches of each paste were prepared in Hauschild beakers. The resulting base paste and catalyst paste were then filled into cartridges. In the following examples, the base paste and catalyst paste were mixed in a 1:1 weight ratio using static mixers.

[0108] Viscosity measurements

[0109] According to Figure 1, the complex viscosity was measured on a HAAKE™ RheoStress™ 1 rotational rheometer in oscillation mode at 30 °C and expressed as | r|* | [Pas] vs. t [min], continuously increasing the shear rate to 8 Hz. Upon subsequent reduction of the shear rate, the viscosity was measured at 3 Hz. The complex viscosity after 10 min corresponds to the maximum value, tgo corresponds to the time at 90% of this value, and ts to the time at 5% of the maximum value.

[0110] Procedure: The complex viscosity is measured during curing using a rheometer at 30 °C. The material cures on the oscillation rheometer for 10 minutes. The final viscosity is read after 10 minutes, and the values ​​ts (time at 5% of the final viscosity) and tgo (time at 90% of the final viscosity) are calculated from this. The times are obtained by extrapolating the curves at the corresponding viscosity value.

[0111] Measurement conditions for viscosity measurement

[0112] RheoStress 1 device

[0113] Manufacturer Thermo Scientific

[0114] Measuring device plate / plate, profiled

[0115] Measuring geometry P20 Ti LS

[0116] Measuring plate attachment MPC20 S Type rotating body PP20PRO. Measuring temperature 30°C Measuring frequency 1.0 Hz Shear stress 800 Pa Gap height 0.5 mm Gap volume 0.2 ml Rotation mode CS

[0117] Measurement type oscillation

[0118] No change in the viscosity curve visible = abort, or

[0119] Measurement time max 10 min

[0120] The sample amount was: m = (1 ,0 ± 0.1) g

[0121] The difference between tgo and ts in minutes (industrial time) indicates the transition time (defined time window of the curing reaction) from the plastic to the elastic state. The shorter tgo - ts is, the faster the composition cures within this time window.

[0122] Table 1 : Defined time window for curing reaction t = (t 90 - 1 5 ) (min), AT (°C)

[0123] Temperature measurement:

[0124] Description of the method

[0125] 1. A tube (21 mm diameter laminate tube = plastic-coated aluminum tube) is shortened to about 5 cm in length

[0126] 2. The tube is filled with material by discharging it from the cartridge with a static mixer (1:1 systems, 5:1 with a dynamic mixer) until the tube contains approximately 8 g of material. The timer starts when the cartridge is first discharged. The quantities were weighed after the test. 3. The temperature sensor of the measuring device (type: Testo 925) is placed in the mass. After 15 seconds, the first measurement is recorded.

[0127] 4. Starting at 30 seconds, the temperature is recorded every 30 seconds until 10 minutes. At this point, all samples have already passed the maximum temperature and the temperature steadily decreases.

[0128] 5. Sample is removed from the temperature measuring device and weighed (m = 8 g + / - 0.5 g).

[0129] Mixture of poldimethylsiloxane (PDMS oil)

[0130] Polydimethylsiloxane with terminal vinyl groups, (vinyl content: 0.13 mmol / g) Polydimethylsiloxane with terminal vinyl groups (vinyl content: 0.05 mmol / g)

[0131] The vinyl content in the base pastes of the following examples is:

[0132] Content of C=C groups: (0.066 to 0.076) mmol / g. The content of C=C groups increases from Example 1 to Example 7.

[0133] Mixture of polydimethylsiloxane (PDMS oil):

[0134] The vinyl content in the catalyst pastes of the following examples is:

[0135] Content of C=C groups: 0.088 mmol / g

[0136] Comparative examples (modified reference examples): In the examples of WO2013 / 025494, Example 1, B / A, no information on the vinyl content or C=C content is disclosed, therefore the vinyl content was adjusted analogously to the above base and catalyst pastes.

[0137] Crosslinker: Poly(methyl)(hydrogen)siloxane crystalline SiO2: cristobalite

[0138] Palladium dispersion (Pd dispersion): Palladium chloride dispersion in divinylpolydimethylsiloxane

[0139] Catalyst: Platinum tetramethyldivinyldisiloxane complex, Karstedt catalyst preparation (4 wt.% Pt)

[0140] The mixing ratio of base paste and catalyst paste of the impression materials is 1:1 unless otherwise stated. Therefore, the examples provided as reference examples are not comparative examples according to the state of the art, but internal reference examples. Table 2:

[0141] Table 3:

[0142] * It was reworked with our own silicone oil content vinyl groups as a comparison example, Table 4:

[0143] Table 5:

[0144] Table 6:

[0145] The compositions according to the invention can be used to provide fast-setting compositions that have very short time windows for the curing reaction tgo - ts, in particular tgo - ts less than or equal to 0.8, while simultaneously avoiding excessive temperature increases. The temperature increase of the compositions according to the invention is preferably below 7°C, more preferably less than or equal to 6°C, and particularly preferably less than or equal to 5°C.

Claims

Patent claims 1 . A curable composition comprising addition-crosslinkable organofunctional polysiloxanes comprising i. addition-crosslinking polysiloxanes containing at least two terminal ethylene groups and ii.at least two polysiloxanes containing Si-H groups, wherein the polysiloxanes containing Si-H groups comprise at least two polysiloxane compositions with different contents of Si-H groups, wherein a first polysiloxane composition (PS1) has a content of Si-H groups of 1 to 3.5 mmol / g and a second polysiloxane composition (PS2) has a content of Si-H groups of 3.8 mmol / g to 15 mmol / g, wherein the first polysiloxane composition (PS1) with a content of Si-H groups and the second polysiloxane composition (PS2) with a content of Si-H groups are present in a weight ratio of 1:1.5 to 1:10, and wherein the molar ratio of Si-H groups of the polysiloxanes to ethylene groups of the polysiloxanes is from 4:1 to 10:1, and optionally comprising a Hydrosilylation catalyst, wherein the curable composition substantially does not comprise a monounsaturated compound of formula I. R 2 R 3 C=CR1 -A-SiR3(I) with R is each independently selected from H, monovalent alkyl group having 1 to 22 C atoms, aryl group having 16 to 12 C atoms, O-SiR 4 3-group, where R optionally comprises heteroatoms, with the proviso that R is not an alkoxy group or arylalkoxy group, R 1 , R 2 , R 3 are each independently selected from H, monovalent alkyl group having 1 to 22 C atoms, aryl group having 6 to 12 C atoms and optionally each independently comprise heteroatoms, R 4 a monovalent alkyl group having 1 to 22 C atoms or aryl group having 6 to 12 C atoms, optionally two or three R 4 Residues in O-SiR 4 3form a cyclic or polycyclic structure, A is a bivalent linear, branched or cyclic hydrocarbon group having 1 to 12 C atoms, optionally comprising an aromatic with at least one methylene group which is directly covalently bonded to the aromatic, optionally comprising -O atoms 2. Composition according to claim 1, characterized in that the addition-crosslinking polysiloxanes containing at least two terminal ethylene groups comprise polydialkylsiloxanes, polydialkylsiloxane ethers or mixtures thereof, in particular with alkyl each independently having 1 to 16 C atoms, in particular each methyl group.

3. Composition according to claim 1 or 2, characterized in that the maximum temperature increase (AT) during curing is less than or equal to 7 °C, wherein the temperature increase is measured with a temperature sensor in the mass in a time interval of 15 seconds from the first mixing to 10 minutes after the first mixing, in particular wherein a temperature measurement is carried out every 30 seconds.

4. Composition according to one of claims 1 to 3, characterized in that the (i) maximum temperature increase (AT) during curing is less than or equal to 6 °C, wherein the temperature increase is carried out with a temperature sensor in the mass in a time interval of 15 seconds from the first mixing to 10 minutes after the first mixing, in particular wherein a temperature measurement is carried out every 30 seconds, and / or (ii) the value ts in minutes of the complex viscosity of 5% of the complex viscosity of the value of the complex viscosity after 10 minutes after the start of mixing of the curable composition is less than or equal to 1.7 minutes, and / or (iii) the value tgo- ts as the difference between the time tgo at 90% of the complex viscosity of the value of the complex viscosity reached after 10 minutes and the time ts at 5% of the complex viscosity of the value of the complex viscosity reached after 10 minutes is less than or equal to 1 minute.

5. Composition according to one of claims 1 to 4, characterized in that the composition does not comprise any content of tetraallylsilane.

6. Composition according to one of claims 1 to 5, characterized in that it comprises at least one surfactant comprising a polyether, polyether-functionalized siloxane oligomer, fatty alcohol and / or fluorosurfactant or mixtures of the aforementioned surfactants.

7. Composition according to one of claims 1 to 6, characterized in that the addition-crosslinking compounds containing at least two terminal ethylene groups Polysiloxanes have an ethylene group content of 0.01 mmol / g to 10 mmol / g ethylene groups, in particular vinyl groups.

8. Composition according to one of claims 1 to 7, characterized in that the first polysiloxane composition (PS1) has a content of Si-H groups of 1 to 3.0 mmol / g, preferably a content of Si-H groups of 1.3 to 2.5 mmol / g, preferably a content of Si-H groups of 1.4 to 2.5 mmol / g.

9. Composition according to one of claims 1 to 8, characterized in that the second polysiloxane composition (PS2) has a content of Si-H groups of 3.9 mmol / g to 10 mmol / g, preferably a content of Si-H groups of 4.0 to 5.0 mmol / g, in particular 4.1 to 5.0 mmol / g, alternatively preferably a content of Si-H groups of 4.0 to 8.0 mmol / g, in particular 4.1 to 8.0 mmol / g.

10. Composition according to one of claims 1 to 9, characterized in that the molar ratio of Si-H groups of the polysiloxanes to ethylene groups of the polysiloxanes is from 3.5:1 to 10:1, in particular from 6:1 to 10:

1.

11. Composition according to one of claims 1 to 10, characterized in that the first and second polysiloxane compositions are present as a mixture, the first polysiloxane composition (PS1) and the second polysiloxane composition (PS2) being present in a weight ratio of 1:3 to 1:10, in particular in a weight ratio of 1:4 to 1:

6.

12. Composition according to one of claims 1 to 10, characterized in that the first polysiloxane composition (PS1) and the second polysiloxane composition (PS2) are present in a weight ratio of 1:1.5 to 1:2.2, in particular in a weight ratio of 1:1.5 to 1:

2.

13. Composition according to one of claims 1 to 12, characterized in that the curable composition is obtainable by mixing two components to obtain an addition-curing curable composition, wherein the two components comprise: a) base component comprising addition-curing polysiloxanes containing at least two terminal ethylene groups and polydialkylsiloxanes containing Si-H groups, in particular at least two terminal ethylene groups containing polydialkylsiloxanes and polydialkylsiloxanes containing at least two Si-H groups, and b) catalyst component comprising a platinum, rhodium and / or palladium-containing hydrosilylation catalyst and optionally comprising addition-crosslinking polysiloxanes containing at least two terminal ethylene groups and optionally containing polysiloxanes containing at least two Si-H groups, in particular polydialkylsiloxanes containing at least two terminal ethylene groups, and optionally wherein the base component and / or the catalyst component each independently comprise - optionally inorganic fillers, organic particulate polymers, in particular with a particle size of 10 nm to 75 micrometers, and - optional pigments comprising organic or inorganic pigments.

14. Composition according to one of claims 1 to 13, characterized in that - the polydialkylsiloxanes containing at least two terminal ethylene groups are selected from vinyl-terminated polydialkylsiloxanes and vinyl-terminated polyether-functional polydialkylsiloxanes, in particular the vinyl-terminated polydialkylsiloxanes and vinyl-terminated polyether-functional polydialkylsiloxanes are selected from vinyl-terminated polydimethylsiloxanes and vinyl-terminated polyether-functional polydimethylsiloxanes.

15. Composition according to claim 14, characterized in that - the polydialkylsiloxanes containing at least two Si-H groups are selected from polydialkylsiloxanes and polyether-functional polydialkylsiloxanes which contain terminal Si-H groups and optionally -Si(CHs)H groups in the polysiloxane backbone, in particular the polydialkylsiloxanes containing Si-H groups are selected from polydimethylsiloxanes and polyether-functional polydimethylsiloxanes, wherein the polydialkylsiloxanes contain terminal Si-H groups and optionally -Si(CHs)H groups in the polysiloxane backbone.

16. Composition according to one of claims 1 to 15, characterized in that the composition is obtainable by mixing an i) base component and ii) catalyst component, wherein i) the base component comprises 30 to 50 wt.% of polydialkylsiloxanes containing at least two terminal ethylene groups, ii) the catalyst component comprises 20 to 80 wt.% of polydialkylsiloxanes containing at least two terminal ethylene groups, and wherein the ratio of terminal ethylene groups of the base component to terminal ethylene groups of the catalyst component is in a molar ratio of 1:1.1 to 1:

10.

17. Composition according to one of claims 1 to 16, characterized in that the composition is obtainable by mixing an i) base component and ii) catalyst component, wherein i) the base component comprises 30 to 50 wt.% polydialkylsiloxanes containing at least two terminal ethylene groups, 15 to 64 wt.% inorganic fillers, 5 to 30 wt.% polydialkylsiloxanes containing at least two Si-H groups, 1.0 to 15 wt.% of at least one surfactant, and wherein the total of the base component is 100 wt.%, and ii) the catalyst component comprises 20 to 80 wt.% polydialkylsiloxanes containing at least two terminal ethylene groups, 5 to 70 wt.% inorganic fillers, 0.001 to 5.0 wt.% platinum, rhodium or palladium-containing hydrosilylation catalyst, 0 to 15 wt.% of at least one surfactant, and 0 to 10 wt.% organic or inorganic pigments and / or structuring agents, the total sum of the catalyst components being 100 wt.%.

18. Kit comprising a 2K dispensing device comprising at least two cartridges, wherein in one cartridge the i) base component according to one of claims 13 to 17 and in the second cartridge contains ii) catalyst components according to any one of claims 13 to 17.

19. Use of a composition according to any one of claims 1 to 17 or of a kit according to claim 18 for making impressions in the medical, dental and / or veterinary fields, for making impressions in the botanical field, for making impressions in the marine and aquatic fields, for making impressions of the surfaces of articles, for making impressions of design, art or craft objects, as a dental impression material, as an impression material for human, veterinary or marine soft (tissue) and / or hard structures (bones, shells, coral), oral impressions, podiatry, for making impressions of electronic components, for making impressions of objects whose surfaces are wetted with aqueous compositions or whose surfaces are wetted with water and / or for printing three-dimensional structures, in particular in the semiconductor field.

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