Radiation-crosslinkable composition containing Pt(octane-2,4-dione)2 as a catalyst

Abstract

The subject of the present invention is a silicone composition X which is crosslinkable by a polyaddition reaction to form a silicone elastomer. The subject of the present invention is in particular a silicone composition X which is crosslinkable by photon irradiation catalyzed by a hydrosilylation catalyst C which is Pt(octane-2,4-dione)2.

Description

[Technical field]

[0001] The subject of the present invention is a silicone composition X which is crosslinkable by a polyaddition reaction to form a silicone elastomer. The subject of the present invention is in particular a silicone composition X which is crosslinkable by photon irradiation and which is catalyzed by a hydrosilylation catalyst C which is Pt(octane-2,4-dione)2. [Background technology]

[0002]

[0002] Silicone compositions crosslinkable by polyaddition reactions are generally thermally crosslinked in the presence of platinum catalysts, in particular Karstedt's catalyst. However, some years ago, compositions crosslinkable by irradiation were developed. This type of composition crosslinkable by irradiation is very useful in particular for coating-type applications in which a substrate is covered with a silicone coating. Furthermore, this type of method has the advantage that savings can be achieved due to the consumption of less energy than thermal methods. This is especially true when irradiation is carried out by UV-LED systems.

[0003]

[0003] Patent application WO9525734 describes photoactive organoplatinum complexes for crosslinking by hydrosilylation of SiH and SiVi organopolysiloxanes. These photoactive organoplatinum complexes are prepared by reacting photosensitive ligands with Karstedt complexes. Nevertheless, the systems described in that application do not serve to obtain both good reactivity under UV (rapid crosslinking under irradiation) and good stability of the composition without irradiation (long gel time without irradiation). The described organoplatinum complexes may also have solubility problems in silicone compositions.

[0004]

[0004] It is also known, for example from European Patent EP 0,398,701, to use Pt(acetylacetonate)2 (or Pt(acac)2) as a hydrosilylation catalyst for silicone compositions crosslinkable by irradiation. Nevertheless, Pt(acetylacetonate)2 is suspected of damaging fertility or the fetus (H361-CMR reproductive toxicity category 2).

[0005]

[0005] Moreover, the above systems cannot always be used when irradiation is performed by UV-LED systems. In fact, the fact of operating with mostly monochromatic light sources such as LEDs requires a more precise design of the photocatalytic system in order to maximize the efficiency of the absorption of photons and thus the reactivity of the system.

[0006]

[0006] Therefore, it is necessary to develop a photocatalytic system which can overcome these disadvantages.

[0007] In this context, the present invention aims to meet at least one of the following objectives: One of the objectives of the present invention is to provide a composition that is crosslinkable by UV radiation, in particular by UV-LED.

[0007]

[0008] Another object of the present invention is to provide a radiation crosslinkable composition catalyzed by a composition that is slightly or non-toxic.

[0009] Another object of the present invention is to provide a radiation crosslinkable composition that has good reactivity.

[0008]

[0010] Another object of the present invention is to provide a radiation crosslinkable composition that has good stability without irradiation.

[0011] It is another object of the present invention to provide a photocatalytic system that has good solubility in a silicone composition. Summary of the Invention

[0009]

[0012] These objectives are, inter alia: a. C2 to C bonded to silicon 12 At least one organopolysiloxane A having at least two alkenyl groups per molecule therein; b. at least one organopolysiloxane B having at least two SiH units per molecule; c. a catalytically effective amount of at least one hydrosilylation catalyst C, which is Pt(octane-2,4-dione)2; This is achieved according to the invention in the first place with respect to a radiation crosslinkable silicone composition X, which comprises

[0010]

[0013] Surprisingly, the inventors have shown that Pt(octane-2,4-dione)2, in contrast to Pt(acac)2, has the advantage of not being mutagenic. Indeed, the compound was analyzed by the Ames test (the Ames test is a commonly used method that uses bacteria to verify whether a given chemical product can cause DNA mutations in the tested organism). The Ames test was unexpectedly conclusive, and Pt(octane-2,4-dione)2 did not induce any mutagenic changes in the tested microorganisms.

[0011]

[0014] Moreover, the fact that catalyst C, which is Pt(octane-2,4-dione)2, is used plays a role in increasing the reactivity of silicone composition X under irradiation, especially under UV-LED irradiation. Silicone composition X therefore crosslinks more rapidly than with Pt(acac)2 or other Pt β-diketonate complexes. Finally, silicone composition X is very stable when not irradiated. Therefore, non-crosslinked silicone composition X protected from light can be stored for several tens of days.

[0012]

[0015] Catalyst C, Pt(octane-2,4-dione)2, also has very good solubility in silicone compositions, which is advantageous over other Pt β-diketonate complexes, for example.

[0013]

[0016] The composition X according to the invention therefore has many advantages: it has good stability and good reactivity, the catalyst C, which is Pt(octane-2,4-dione)2, has good solubility in the silicone composition and is not a mutagenic compound according to the Ames test.

[0014]

[0017] The subject of the present invention is also a method for the preparation of a coating on a support, comprising the following steps: - application of a silicone composition X to a substrate, preferably a textile substrate; - crosslinking of said composition by electron or photon irradiation, preferably by exposure to electron beams, by exposure to gamma radiation or by exposure to radiation having a wavelength comprised between 100 nm and 450 nm, preferably UV radiation; The method includes:

[0015]

[0018] Another subject of the invention is a coated substrate obtainable according to said process.

[0019] Another subject of the invention is the use of silicone composition X for the preparation of silicone elastomers.

[0016]

[0020] Another object of the present invention is to provide - C2 to C bonded to silicon 12 At least one organopolysiloxane A having at least two alkenyl groups per molecule therein; at least one hydrosilylation catalyst C which is Pt(octane-2,4-dione)2; A premix for a silicone composition comprising:

[0017]

[0021] definition In the present application, "silicone composition crosslinkable by radiation" is understood to mean a silicone composition containing at least one organopolysiloxane that can be cured by electron or photon radiation. Exposure to electron beams can refer to one of electron radiation. Exposure to UV rays or gamma rays can refer to one of photon radiation. Preferably, the irradiation is by exposure to radiation having a wavelength comprised between 100 nm and 450 nm or between 200 nm and 405 nm.

[0018]

[0022] As used herein, "UV" means ultraviolet. Ultraviolet radiation is defined as electromagnetic radiation having wavelengths beyond the visible light spectrum, comprised between about 100 nm and about 405 nm.

[0019]

[0023] Additionally, in this text, "LED" is an abbreviation for "light emitting diode," a term well known to those skilled in the art.

[0024] Unless otherwise indicated, all viscosities of silicone oils discussed in this disclosure correspond to a measure of dynamic viscosity at 25° C. referred to as “Newtonian”, and refer to dynamic viscosity as measured in a well-known manner using a Brookfield viscometer, and with sufficiently low shear rate gradients such that the viscosity measured is independent of velocity gradients.

[0020]

[0025] In this specification, "fabric" is a general term that covers all textile structures. Fabrics may be composed of threads, fibers, filaments and / or other materials. They include particularly soft fabrics, whether woven, bonded, knitted, braided, felted, needle embroidered, embellished or made by another mode of production. "Yarn" is understood to mean a continuous multifilament body, a continuous thread obtained from an assembly of several threads, or a continuous fiber thread obtained from a single type of fiber or a mixture of fibers. "Fiber" is understood to mean the manufacture of nonwoven articles or tow, for example, intended to be cut to form short or long fibers, fibers processed by spinning, or short fibers. The textile may in particular be made of yarns, fibers and / or filaments that have undergone one or more processing steps, such as, for example, texturing, drawing, drawing-texturing, oiling, relaxation, thermal setting, twisting, fixing, clapping, washing and / or dyeing steps, prior to producing the textile surface.

[0021]

[0026] In this application, all percentages and ppm are by weight unless otherwise indicated. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022]

[0027] Crosslinkable silicone composition X

[0028] The object of the present invention is to a. C2 to C bonded to silicon 12 At least one organopolysiloxane A having at least two alkenyl groups per molecule therein; b. at least one organopolysiloxane B having at least two SiH units per molecule; c. a catalytically effective amount of at least one hydrosilylation catalyst C, which is Pt(octane-2,4-dione)2; The silicone composition X is crosslinkable by irradiation, comprising:

[0023]

[0029] According to an embodiment, composition X is crosslinkable by exposure to radiation having a wavelength comprised between 100 nm and 450 nm, in particular UV radiation.

[0030] Silicon-bonded C2-C 12 The organopolysiloxane A having at least two alkenyl groups per molecule is - The following formula: Y a R 1 b SiO (4-a-b) / 2 At least two siloxyl functional groups (In the formula, Y is C2~C 12 alkenyl, preferably vinyl; R 1 is a monovalent hydrocarbon radical having 1 to 12 carbon atoms, preferably selected from alkyl radicals having 1 to 8 carbon atoms, such as methyl, ethyl and propyl radicals, which may be substituted by at least one halogen atom, such as chlorine or fluorine, cycloalkyl radicals having 3 to 8 carbon atoms, and aryl radicals having 6 to 12 carbon atoms; a=1 or 2, b=0, 1 or 2, a+b=1, 2 or 3) In some cases, the formula: 1 c SiO (4-c) / 2 Functional group (In the formula, R 1 has the same meaning as above, and c=0, 1, 2 or 3), may in particular be formed.

[0024]

[0031] Multiple R 1 It is understood in the above formula that, when groups are present, they may be the same or different from one another.

[0032] These organopolysiloxanes A contain the siloxy functional group YSiO 2 / 2 , Y.R. 1 SiO 2 / 2 and R 1 2SiO 2 / 2a siloxy functional group "D" selected from the group consisting of 1 2SiO 1 / 2 , Y2R 1 SiO 1 / 2 and R 1 3SiO 1 / 2 The symbols Y and R may have a linear structure consisting essentially of terminal siloxy functional groups "M" selected from the group consisting of 1 is as described above.

[0025]

[0033] The following groups may be mentioned as examples of terminal functional groups "M": trimethylsiloxy, dimethylphenylsiloxy, dimethyl(vinyl)siloxy or dimethylhexenylsiloxy.

[0026]

[0034] The following groups may be mentioned as examples of the functional group "D": dimethylsiloxy, methylphenylsiloxy, diphenylsiloxy, methyl(vinyl)siloxy, methylbutenylsiloxy, methylhexenylsiloxy, methyldecenylsiloxy or methyldecadienylsiloxy.

[0027]

[0035] The following: - a poly(dimethylsiloxane) having a terminal dimethyl(vinyl)silyl group; - poly(dimethylsiloxane-co-methylphenylsiloxane) having terminal dimethyl(vinyl)silyl groups; - poly(dimethylsiloxane-co-methylvinylsiloxane) having terminal dimethyl(vinyl)silyl groups; - a trimethylsilyl terminated poly(dimethylsiloxane-co-methyl(vinyl)siloxane); - cyclic poly(methyl(vinyl)siloxane); are some examples of organopolysiloxanes which may be organopolysiloxane A according to the present invention.

[0028]

[0036] In its most preferred form, organopolysiloxane A contains terminal dimethyl(vinyl)silyl functional groups, and even more preferably, organopolysiloxane A is a poly(dimethylsiloxane) having terminal dimethyl(vinyl)silyl.

[0029]

[0037] Silicone oils generally have a viscosity comprised between 1 mPa·s and 2,000,000 mPa·s. Preferably, said organopolysiloxane A is an oil having a dynamic viscosity comprised between 20 mPa·s and 300,000 mPa·s, preferably between 100 mPa·s and 200,000 mPa·s at 25° C., and more preferably between 600 mPa·s and 150,000 mPa·s.

[0030]

[0038] Optionally, the organopolysiloxane A may contain siloxyl functional groups "T" (R 1 SiO 3 / 2 ) and / or siloxyl functional group "Q" (SiO 4 / 2 R 1 is as described above. Then, organopolysiloxane A has a branched structure. - poly(dimethylsiloxanes) (methylsiloxanes) having terminal trimethylsilyl and dimethyl(vinyl)silyl groups, which are composed of "M" trimethylsiloxy, "M" dimethyl(vinyl)siloxy, "D" dimethylsiloxy and "T" methylsiloxy functional groups; - a resin composed of "M" trimethylsiloxy, "M" dimethyl(vinyl)siloxy and "Q" functional groups; - a resin composed of "M" trimethylsiloxy, "D" methyl(vinyl)siloxy and "Q" functional groups; are some examples of branched organopolysiloxanes which may be organopolysiloxane A according to the present invention.

[0031]

[0039] However, according to an embodiment, the silicone composition X is a branched organopolysiloxane or a C2-C 12The resin does not include resins containing alkenyl functional groups having the formula:

[0040] Preferably, the organopolysiloxane compound A has an alkenyl functional group concentration by mass comprised between 0.001% and 30%, preferably between 0.01% and 10%, preferably between 0.02 and 5%.

[0032]

[0041] Silicone composition X preferably contains 50% to 95% by weight of organopolysiloxane A, more preferably 60% to 87% by weight of organopolysiloxane A, and even more preferably 70% to 85% by weight of organopolysiloxane A, based on the total weight of silicone composition X.

[0033]

[0042] The silicone composition X may comprise a single organopolysiloxane A or a mixture of several organopolysiloxanes A, for example having different viscosities and / or different structures.

[0034]

[0043] Organopolysiloxane B is an organohydrogenpolysiloxane containing at least two, and preferably at least three, hydrogensilyl or Si-H functional groups per molecule.

[0035]

[0044] The organohydrogenpolysiloxane B advantageously comprises at least two, preferably at least three, groups of the following formula: d R 2 e SiO (4-d-e) / 2 (In the formula, - Radical R 2 (s) are the same or different and represent monovalent radicals having 1 to 12 carbon atoms; - d=1 or 2, e=0, 1 or 2, d+e=1, 2 or 3) and a siloxyl functional group having the formula: In some cases, the formula: 2 f SiO (4-f) / 2 (In the formula, R 2has the same meaning as above, where f=0, 1, 2 or 3) and another functional group having the formula: The organopolysiloxane may be an organopolysiloxane comprising:

[0036]

[0045] In the above formula, multiple R 2 It is understood that when groups are present, they may be the same or different from each other. 2 may represent a monovalent radical selected from the group consisting of alkyl groups having 1 to 8 carbon atoms, cycloalkyl groups having 3 to 8 carbon atoms, and aryl groups having 6 to 12 carbon atoms, which may be substituted with at least one halogen atom, such as chlorine or fluorine. 2 may advantageously be chosen from the group consisting of methyl, ethyl, propyl, 3,3,3-trifluoropropyl, xylyl, tolyl and phenyl.

[0037]

[0046] In the above formula, the symbol d is preferably equal to 1.

[0047] The organohydrogenpolysiloxane B may have a linear, branched or cyclic structure. The degree of polymerization is preferably greater than or equal to 2. Generally, the degree of polymerization is less than 5000.

[0038]

[0048] When the organohydrogenpolysiloxane B is accompanied by linear polymers, these linear polymers have the following formula D:R 2 2SiO 2 / 2 or D′:R 2 HSiO 2 / 2 and a siloxyl functional group selected from functional groups having the following formula M:R 2 3SiO 1 / 2 or M′:R 2 2HSiO 1 / 2 wherein R 2 have the same meaning as above).

[0039]

[0049] Some examples of organohydrogenpolysiloxanes that contain at least two hydrogen atoms bonded to silicon atoms and that can be organopolysiloxane B according to the invention are: - a poly(dimethylsiloxane) having a terminal hydrogenmethylsilyl group; - a trimethylsilyl terminated poly(dimethylsiloxane-co-methylhydrogensiloxane); - poly(dimethylsiloxane-co-methylhydrogensiloxane) having hydrogendimethylsilyl terminal groups; - a trimethylsilyl-terminated poly(methylhydrogensiloxane); - cyclic poly(methylhydrogensiloxane); It is.

[0040]

[0050] When the organohydrogenpolysiloxane B has a branched structure, the branched structure preferably has the following formula: - M'Q, where the hydrogen atom bonded to the silicon atom is attached on the M group, - MM'Q, where the hydrogen atom bonded to the silicon atom is attached to a part of the M functional group, - MD'Q, where the hydrogen atom bonded to the silicon atom is attached to a D group, - MDD'Q, where the hydrogen atom bonded to the silicon atom is attached to a part of the D group, - MM'TQ, where the hydrogen atom bonded to the silicon atom is attached to a part of the M functional group; - MM'DD'Q, where the hydrogen atoms bonded to the silicon atoms are linked by part of the M and D functional groups, - mixtures thereof, and wherein the silicone resin is selected from the group consisting of silicone resins having the formula: M, M′, D and D′, T as previously defined: 2 3SiO 1 / 2 and Q: a siloxyl functional group having the formula SiO 4 / 2 wherein R 2 have the same meaning as above).

[0041]

[0051] Preferably, the organohydrogenpolysiloxane compound B has a mass concentration of hydrogensilyl functional groups Si—H comprised between 0.2% and 91%, more preferably between 3% and 80%.

[0042]

[0052] Considering now the silicone composition X as a whole, the molar ratio of hydrogensilyl functional groups Si—H to alkenyl functional groups may advantageously be comprised between 0.2 and 20, preferably between 0.5 and 15, more preferably between 0.5 and 10, and even more preferably between 0.5 and 5.

[0043]

[0053] Preferably, the viscosity of organohydrogenpolysiloxane B is comprised between 1 mPa·s and 5000 mPa·s, more preferably between 1 mPa·s and 2000 mPa·s, and even more preferably between 5 mPa·s and 1000 mPa·s.

[0044]

[0054] Silicone composition X preferably contains 0.1% to 10% of organohydrogenpolysiloxane B, and even more preferably 0.5% to 5%, by weight based on the total weight of silicone composition X.

[0045]

[0055] The silicone composition X may comprise a single organohydrogenpolysiloxane B or a mixture of several organohydrogenpolysiloxanes B, for example having different viscosities and / or different structures.

[0046]

[0056] According to an embodiment, the silicone composition X is - at least one organohydrogenpolysiloxane B as described above, containing two SiH functional groups per molecule, - at least one organohydrogenpolysiloxane B as described above, containing at least three SiH functional groups per molecule; The mixture may include:

[0047]

[0057] In the context of the present invention, the hydrosilylation catalyst C is Pt(octane-2,4-dione)2. The amount by weight of catalyst C, calculated by the weight of metallic platinum, is generally comprised between 1 and 400 ppm, preferably between 2 and 200 ppm, and more preferably between 5 and 100 ppm, based on the total weight of silicone composition X.

[0048]

[0058] Pt(octane-2,4-dione)2 exists as two diastereomers, cis and trans.

[0049] [ka]

[0050] cis,

[0051] [ka]

[0052] trans has.

[0059] The cis:trans ratio in the hydrosilylation catalyst C is comprised between 0:100 and 100:0. Therefore, only the cis diastereomer, only the trans diastereomer or a mixture of the two diastereomers can be used as the hydrosilylation catalyst C.

[0053]

[0060] According to an embodiment, Pt(octane-2,4-dione)2 is a mixture of cis and trans diastereomers. The cis:trans ratio may be comprised between 90:10 and 10:90, or between 75:25 and 25:75. According to a particular embodiment, the mixture comprises a majority of cis diastereomers.

[0054]

[0061] Pt(octane-2,4-dione)2 can be synthesized by reacting an octane-2,4-dione ligand with a platinum precursor such as K2PtCl4 in the presence of a base such as NaOH.

[0055]

[0062] The silicone composition X according to the invention may contain a crosslinking inhibitor D. Crosslinking inhibitors are intended to slow down the crosslinking reaction and are also called retarders. Crosslinking inhibitors are well known from the prior art. The following may be mentioned as examples: cyclic polymethylvinylsiloxanes and acetylenic alcohols as described in patent US 3,923,705, acetylenic alcohols as described in patent US 3,445,420, heterocyclic amines as described in patent US 3,188,299, diallyl maleate and other dialkyl esters as described in patent US 4,256,870, olefinic siloxanes as described in patent US 3,989,667, and dialkylethynedicarboxylates as described in patent US 4,347,346. The following classes of inhibitors may also be mentioned: hydrazines, triazoles, phosphines, mercaptans, nitrogenous organic compounds, acetylenic alcohols, silylacetylenic alcohols, maleic acid, fumaric acid, ethylenically or aromatically unsaturated amides, unsaturated ethylene isocyanates, olefinic siloxanes, unsaturated hydrocarbon monoesters and diesters, conjugated eneines, hydroperoxides, nitriles and diaziridines. The crosslinking inhibitor D is preferably 1,3,5,7-tetramethyl-1,3,5,7-tetravinyl-cyclotetrasiloxane, 1-ethynyl-1-cyclohexanol (ECH), 3-methyl-1-butyn-3-ol, 2-methyl-3-butyn-2-ol, 3-butyn-1-ol, 3-butyn-2-ol, propargyl alcohol, 2-phenyl-2-propyn-1-ol, 3,5-dimethyl-1-hexyn-3-ol, 1-ethynylcyclopentasiloxane ... The aryl alcohol may be selected from the group consisting of ethanol, 1-phenyl-2-propynol, 3-methyl-1-penten-4-yn-3-ol, 3-methyl-1-dodecin-3-ol, 3,7,11-trimethyl-1-dodecin-3-ol, ordiphenyl-1,1-propyne-2-ol-1, 3,6-diethyl-1-nonin-3-ol, 3-methyl-1-pentadecin-3-ol, and mixtures thereof.Acetylenic alcohols are highly preferred crosslinking inhibitors D according to the invention, more particularly 1-ethynyl-1-cyclohexanol (ECH). According to an embodiment, the silicone composition X comprises between 2 and 10,000 ppm of crosslinking inhibitor D, preferably between 5 and 1000 ppm, relative to the total weight of the silicone composition X.

[0056]

[0063] The crosslinkable silicone composition X may comprise a filler E. According to an embodiment, the silicone composition X comprises between 5% and 40% by weight of filler E relative to the total weight of the silicone composition X. Advantageously, the silicone composition X comprises between 8% and 20% by weight of filler E.

[0057]

[0064] The filler E that may be provided is preferably inorganic. It may be a very finely divided product, the average specific diameter of which is less than 0.1 μm. The filler E may in particular be silica-based. As regards the silica-based material, it may play the role of a reinforcing or semi-reinforcing filler. The reinforcing silica-based fillers are chosen from colloidal silica, silica combustion and precipitation powders, or mixtures thereof. These powders generally have an average particle size below 0.1 μm and a specific diameter of 30 μm. 2 / g, preferably from 30 to 350 m 2 / g. Semi-reinforcing silica-based fillers such as diatomaceous earth and / or ground quartz may also be used. These silicas may be incorporated as such or after being treated with organosilica compounds typically used for this purpose. These compounds include methylpolysiloxanes such as hexamethyldisiloxane, octamethylcyclotetrasiloxane, methylpolysilazanes such as hexamethyldisilazane, hexamethylcyclotrisilazane, tetramethyldivinyldisilazane, chlorosilanes such as dimethyldichlorosilane, trimethylchlorosilane, methylvinyldichlorosilane, dimethylvinylchlorosilane, alcoxysilanes such as dimethyldimethoxysilane, dimethylvinylethoxysilane, trimethylmethoxysilane, and mixtures thereof. As for non-silica-based inorganic materials, they may be involved as semi-reinforcing inorganic fillers or filler materials. Examples of these non-siliceous fillers, which may be used alone or in admixture, are calcium carbonate, which may be surface treated with organic acids or with organic acid esters, calcined clay, rutile titanium dioxide, oxides of iron, zinc, chromium, zirconium, and magnesium, various forms of alumina (hydrated or non-hydrated), boron nitride, lithopone, barium metaborate, barium sulfate, and glass microbeads. These fillers are coarse, generally with an average particle size greater than 0.1 μm, and generally with a particle size of 30 μm or less. 2 / g. These fillers may be surface modified by treatment with various organosilica compounds typically used for this purpose.

[0058]

[0065] Preferably, filler E is silica, and even more preferably fumed silica. The silica is advantageously of a 75 to 410 m 2 / g.

[0059]

[0066] Silicone composition X may also contain other functional additives typical of silicone compositions. The following may be listed as a family of functional additives: adhesion promoters, adhesion modulators, silicone resins, additives for increasing viscosity, additives for heat resistance, oil resistance, fire resistance, such as metal oxides, virucides, fungicides, antiwear additives, and pigments (organic or inorganic).

[0060]

[0067] According to a preferred embodiment, the silicone composition X according to the invention comprises, based on the total weight of the silicone composition X: - 50% to 95%, preferably 60% to 87%, of C2 to C bonded to silicon 12 an organopolysiloxane A having at least two alkenyl groups per molecule therein; - 0.1% to 10%, preferably 0.5% to 5%, of organopolysiloxane B having at least 2 SiH units per molecule, - a hydrosilylation catalyst C of Pt(octane-2,4-dione)2 in an amount of from 1 ppm to 400 ppm, preferably from 2 ppm to 200 ppm, and more preferably from 5 to 100 ppm (calculated in parts per million of metal); - if necessary, preferably between 5% and 40% of filler E Includes.

[0061]

[0068] Silicone Composition X can be prepared by mixing all of the various ingredients described above.

[0069] According to an embodiment, the silicone composition X according to the invention may be prepared from a two-component system, characterized in that it has two different parts intended to be mixed to form said silicone composition X, one of which comprises the catalyst C and does not comprise the organopolysiloxane B, and the other of which comprises the organopolysiloxane B and does not comprise the catalyst C.

[0062]

[0070] Alternatively, the silicone composition X according to the present invention may be a single component system.

[0071] Another object of the present invention is to provide - C2 to C bonded to silicon 12 At least one organopolysiloxane A having at least two alkenyl groups per molecule therein; at least one hydrosilylation catalyst C which is Pt(octane-2,4-dione)2; A premix for a silicone composition comprising:

[0063]

[0072] In said premix, the amount by weight of hydrosilylation catalyst C, calculated by the weight of metallic platinum, is generally comprised between 0.1% and 10%, based on the total weight of the premix.

[0064]

[0073] The pre-mixture may optionally contain a co-solvent, for example hexamethyldisiloxane or a short silicon oil, typically having a viscosity below 100 mPa·s.

[0065]

[0074] Method for the preparation of a coating on a substrate

[0075] The present invention relates to a method for the preparation of a coating on a substrate, comprising the following steps: - application of a silicone composition X to a substrate, preferably a textile substrate; - crosslinking of said composition by electron or photon irradiation, preferably by exposure to electron beams, by exposure to gamma radiation or by exposure to radiation having a wavelength comprised between 100 nm and 450 nm, preferably UV radiation; The present invention also relates to a method comprising the steps of:

[0066]

[0076] The step of applying silicone composition X can be done by continuously or discontinuously depositing said silicone composition X onto at least one surface of said support.

[0077] Deposition can typically be achieved by transfer with a kiss roll or by spraying using a nozzle, a doctor blade, a rotating screen or a reverse roll. The thickness of the layer with silicone composition X deposited on the support can be comprised between 0.1 mm and 0.8 mm, preferably between 0.3 mm and 0.6 mm, and even more preferably between 0.4 mm and 0.5 mm.

[0067]

[0078] According to an embodiment, the crosslinking step of the method according to the invention is performed by UV radiation having a wavelength comprised between 100 nm and 405 nm. According to a preferred embodiment of the invention, the radiation is ultraviolet light having a wavelength equal to or less than 405 nm. According to a preferred embodiment of the invention, the radiation is ultraviolet light having a wavelength greater than 100 nm.

[0068]

[0079] UV radiation can be emitted by doped or undoped mercury vapor lamps with an emission spectrum extending from 100 nm to 405 nm. Light sources such as light emitting diodes, better known by the acronym "LED", which emit points of UV or visible light, can also be used.

[0069]

[0080] According to a preferred embodiment, the crosslinking of the silicone composition X is carried out by irradiation with UV rays, the source of which is a UV-LED lamp. The UV-LED lamp can emit radiation with wavelengths of 365 nm, 385 nm, 395 nm or 405 nm. Preferably, the UV-LED lamp is a lamp that emits at 395 nm.

[0070]

[0081] The power of the UV-LED lamp is preferably 2W / m 2 to 200,000 W / m 2 is included between.

[0082] According to a preferred embodiment, the irradiation of silicone composition X is carried out continuously by passing the support under the UV-LED lamp. The speed of the passes and the number of passes can be defined so that the total irradiation of the silicone composition occurs over a time comprised between 1 and 60 seconds, preferably between 2 and 40 seconds, and even more preferably between 3 and 15 seconds. Thus, the energy obtained by the silicone composition X by irradiation is preferably less than 1 J / m 2 from 1200 J / cm 2 Between 100 and 200 mm, preferably 5 J / m 2 from 5J / cm 2 is included between.

[0071]

[0083] According to a preferred embodiment, the crosslinking step is carried out without inerting, nevertheless, proceeding under an inert atmosphere, for example nitrogen, argon or oxygen-depleted air, is not excluded.

[0072]

[0084] The crosslinking step is carried out at a temperature comprised between 15°C and 60°C, more preferably between 20°C and 40°C, and even more preferably at ambient temperature, typically around 25°C.

[0073]

[0085] According to the invention, any type of support may be used, in particular a fabric support. For reference, the following: - Natural fabrics: Fabrics of plant origin such as cotton, linen, hemp, jute, coconut, cellulose fibres from paper, fabrics of animal origin such as wool, fur, leather and silk. - artificial textiles: cellulosic textiles, such as cellulose or its derivatives, and textiles made from proteins of animal or vegetable origin; - Synthetic fabrics: polyester, polyamide, polymalic alcohol, polyvinyl chloride, polyacrylonitrile, polyolefin, acrylonitrile, (meth)acrylate-butadiene-styrene copolymer and polyurethane, etc. may be listed as a fabric support.

[0074]

[0086] Synthetic textiles resulting from polymerization or polycondensation may in particular contain various kinds of additives in the matrix, such as pigments, delusterants, matting agents, catalysts, heat and / or light stabilizers, antistatic agents, flame retardants, antibacterial agents, antifungal agents and / or anti-mite agents.

[0075]

[0087] The following may in particular be mentioned as types of textile surfaces: surfaces resulting from a linear combination of yarns or fabrics, surfaces resulting from a combination of curved loops of yarns or knits, multi-line or tulle surfaces, nonwoven surfaces, and composite surfaces.

[0076]

[0088] The fabric support used in the method according to the present invention is composed of one or more of the same or different fabrics, and can be assembled by various means.The fabric can be single-layered or multi-layered.The fabric support can be composed of a multi-layer structure, which can be produced by various assembly means, such as sewing, welding, or mechanical means such as spot or continuous bonding.

[0077]

[0089] The fabric substrate may, besides the coating method according to the invention, undergo one or more other subsequent treatments, also called finishing or upgrading treatments. These other treatments may be done before, after or during said coating process according to the invention. The following may be listed as other treatments: dyeing, printing, laminating, coating, assembling with other textile materials or surfaces, washing, degreasing, preforming or setting.

[0078]

[0090] According to an embodiment, the support is an open-weave and / or elastic textile support.

[0091] If the fabric contains void spaces that are not composed of fabric, the fabric is called "openwork". The void spaces (which may be designated by pores, gaps, cavities, holes, tears or voids) may or may not be uniformly distributed over the fabric. These void spaces may be created during the preparation of the fabric in particular. For the coating of the silicone composition according to the present invention to be effective, it is preferred that the smallest dimension of these void spaces is less than 5 mm, in particular less than 1 mm.

[0079]

[0092] A fabric is said to be "elastic" if it has a modulus of elasticity greater than 5%, preferably greater than 15%. The modulus of elasticity of a fabric can typically be up to 500%. The modulus of elasticity represents the percentage of the stretch of the fabric when it is fully stretched. The stretch can be in the machine direction only, the cross direction only, or both the machine direction and the cross direction.

[0080]

[0093] The fabric support may be lace or an elastic band.

[0094] Another subject of the invention is a coated substrate obtainable according to said process.

[0081]

[0095] The resulting coated fabric substrates can be used as such or converted into fabric articles, for example in the apparel field, especially as lingerie, such as lace for tops, stockings or brassieres, and sportswear, as well as in hygiene articles, such as elastic bandages or dressings, in many applications.

[0082]

[0096] Other Applications

[0097] The use of Pt(octane-2,4-dione)2 as a hydrosilylation catalyst is also an object of the present invention.

[0083]

[0098] Another subject of the invention is the use of silicone composition X for the preparation of silicone elastomers.

[0099] The invention also relates to the use of composition X according to the invention for the preparation of conformal coatings in the electronics sector, for example for printed circuits and for potting microcircuits and electronic components such as IGBTs.

[0084]

[0100] The present invention also relates to the use of the composition X according to the invention for the preparation of silicone elastomer articles by additive manufacturing methods. Additive manufacturing methods are also known as 3D printing methods. This specification includes throughout the ASTM F2792-12a designation "Standard Terminology for Additive Manufacturing Technologies". In accordance with this ASTM standard, "3D printer" is defined as "a machine used for 3D printing" and "3D printing" is defined as "the manufacture of an object through the deposition of material using a print head, nozzle, or another printing technology".

[0085]

[0101] In contrast to subtractive manufacturing methods, additive manufacturing "AM" is generally defined as the process of layer-by-layer material deposition to produce an object from 3D model data. Synonyms related to and encompassed by 3D printing include additive manufacturing, additive process, additive technology, and layer-by-layer manufacturing. Additive manufacturing (AM) is sometimes also referred to as rapid prototyping (RP). As used herein, "3D printing" is interchangeable with "additive manufacturing" and vice versa.

[0086]

[0102] Irradiation of layers of silicon composition X as printing progresses can result in rapid gelation of at least a portion of the composition during production, allowing each layer to retain its shape without collapse of the printed structure.

[0087]

[0103] Advantageously, the silicone composition X according to the invention can be used for the methods of tank photopolymerization (digital light processing, stereolithography), material extrusion, material deposition or 3D printing carried out in inkjet, by adapting the viscosity of the silicone composition X to the technique used.

[0088]

[0104] Other details or advantages of the invention will become clearer through the examples given below, purely for reference purposes. EXAMPLES

[0089]

[0105] The silicone compositions described below as examples were prepared using the following raw materials: A: poly(dimethylsiloxane) containing approximately 2 wt. % Si-vinyl functional groups and terminal dimethyl(vinyl)silyl groups with a viscosity of ≈100 MPa·s; B: trimethylsilyl terminated poly(methylhydrogensiloxane) containing 56% by weight of SiH functional groups; C1: Pt(octane-2,4-dione)2 prepared according to Example 1; C2: Pt(acac)2 (0.1% solution in dichloromethane), C3: Pt(heptane-3,5-dione)2 prepared according to Example 1 using heptane-3,5-dione; C4: Pt(hexane-2,4-dione)2 prepared according to Example 1 using hexane-2,4-dione; C5: mixture of Pt Karstedt-benzoquinone complexes as described in patent application WO95 / 25734; was obtained from.

[0090] [ka]

[0091] Example 1

[0106] Catalyst C1: Synthesis, properties and toxicity testing of Pt(octane-2,4-dione)2

[0107] A solution of NaOH (3.0 equiv.) in distilled water was added to octane-2,4-dione (4.0 equiv.) and the mixture was stirred at 70° C. for 5 min. K2PtCl4 (500 mg, 1.20 mmol, 1.0 equiv.) was then added and the reaction mixture was stirred at 70° C. in the dark. The reaction immediately changed color from red to orange to yellow and a brown oil separated from the pale aqueous solution. The consumption of octane-2,4-dione was followed by GC-FID and no further change was observed after 4 h. The mixture was then cooled to 25° C. and diluted with CHCl2. The phases were separated and the aqueous phase was extracted again with CHCl2. The combined organic phase was then dried over Na2SO4, filtered and concentrated under reduced pressure to obtain a brown oily residue.

[0092]

[0108] Purification was carried out by flash chromatography on silica gel (cyclohexane / EtOAc 75:25). Two fractions: - 33% yield and 99% purity ( 1 1 H NMR determined mass percent), cis / trans ratio 91 / 9 ( 1 1 H NMR)) - 28% yield and 98% purity ( 1 1 H NMR determined mass percent), cis / trans ratio 4 / 96 ( 1 1 H NMR)) obtained.

[0093]

[0109] Cis-Pt(octane-2,4-dione)2 (toluene-d8, 400 MHz, 25 °C) δ = 5.14 (s, 2H), 1.89 (t, J = 7.6 Hz, 4H), 1.53 (s, 6H), 1.43 (quintet, J = 7.6 Hz, 4H), 1.13 (sexlet, J = 7.2 Hz, 4H), 0.75 (t, J = 7.2 Hz, 6H)

[0110] Trans-Pt(octane-2,4-dione)2(toluene-d8, 400MHz, 25℃)δ = 5.14 (s, 2H), 1.90 (t, J = 7.6 Hz, 4H), 1.52 (s, 6H), 1.44 (quintet, J = 7.6 Hz, 4H), 1.14 (sextet, J = 7.6 Hz, 4H), 0.75 (t, J = 7.2 Hz, 6H)

[0111] Toxicity test (Ames test, described in OECD guidelines for chemical product tests-test 471: Bacterial Reverse Mutation Test): Solutions were prepared with Pt(octane-2,4-dione)2. These solutions did not induce any mutagenic modifications in Salmonella typhimurium TA1535, TA1537, TA98, TA100 and in Escherichia coli WP2(uvrA-)(pKM101) with or without metabolic activation at 5000, 1500, 150 and 50 μg / plate.

[0094] Example 2

[0112] Determination of catalytic activity

[0113] How to operate - A mother liquor of catalyst C1 or C2 is prepared with 600 ppm Pt in hexamethyldisiloxane. - 0.1 mL of mother liquor is added to 5.5 g of organopolysiloxane A, then 0.29 g of organopolysiloxane B is added (molar ratio of SiH / Si(vinyl)=2:1 and metal Pt concentration of 10 ppm). - Irradiate the solution under a stream of compressed air and stirring (500 rpm) until the liquid becomes a gel and the mass becomes unstirrable.

[0095]

[0114] Irradiation: UV LED lamp with a wavelength of 365 nm.

[0115] The crosslinking time is measured, which corresponds to the time when the bulk of the system has hardened (a bar magnet cannot stir the system any more). The results are shown in Table 1.

[0096]

[0116]

[0097] [Table 1]

[0098]

[0117] These results show that the silicone composition according to the invention has excellent properties. In fact, the crosslinking time under UV is shorter than with the reference catalyst Pt(acac)2. Furthermore, Pt(octane-2,4-dione)2 has better solubility in silicone.

[0099] Example 3

[0118] Photo DSC experiment

[0119] The complex was isolated in more than 90% pure form and evaluated by Photo-DSC (DSC=differential scanning calorimetry) using the same component composition as in Example 2 to determine the time of maximum reaction rate.

[0100]

[0120] The time to reach maximum heat flow in mW / s and the peak value are recorded in the following table.

[0101]

[0121] How to operate - Prepare a catalyst mother liquor having 600 ppm Pt in hexamethyldisiloxane. - 30 mg of mother liquor was added to 1.76 g of Organopolysiloxane A, then 48 mg of Organopolysiloxane B was added. The resulting sample had a metallic Pt concentration of 10 ppm. Photo-DSC experiments were performed under N2 purge using a Mettler DSC system equipped with a Hamamatsu spot UV light source model LC8-02. - The heat flow was measured with a DSC while delivering equal photo doses to the sample cup and to an empty reference cup via two waveguides coupled to the instrument. - The light source is a mercury xenon lamp with a 365 nm filter, the UV dose at 365 nm is 14.4 mW / cm 2 It is.

[0102]

[0122] The results are shown in Table 2.

[0123]

[0103] [Table 2]

[0104]

[0124] These results show that the two diastereomers of Pt(octane-2,4-dione)2 have higher thermal peaks than reference catalysts such as Pt(acac)2. A higher peak is desirable because the higher the peak, the higher the activity. Furthermore, the time for the two diastereomers of Pt(octane-2,4-dione)2 to reach the thermal peak is comparable to or less than the other catalysts tested. This indicates good reactivity of Pt(octane-2,4-dione)2.

[0105]

[0125] These results also show that the two diastereomeric Pt(octane-2,4-dione)2 have comparable or improved solubility in the silicone composition compared to the other tested catalysts.

[0106] Example 4

[0126] Determination of catalyst solubility

[0127] The solubility of the various catalysts C1-C5 was determined in hexamethyldisiloxane (HMDSO) at 20°C according to the following protocol. 1) Collect 5 mg of Pt catalyst and add 200 mg of HMDSO. 2) Stir for 5 minutes at 20° C. to suspend the catalyst and saturate the medium. 3) Continue stirring the medium while diluting with HMDSO by successive additions (100 mg each, then 500 mg each, up to a total of 1 g) until a clear medium is obtained with no precipitation observed at the end of the stirring stage. The results are shown in Table 3.

[0107]

[0128]

[0108] [Table 3]

[0109]

[0129] These results show that Pt(octane-2,4-dione)2 (C1) has significantly better solubility in silicones than other Pt-based complexes, especially the other Pt β-diketonates (C3 and C4).

[0110] Example 5

[0130] Determination of catalyst stability

[0131] Solutions containing catalysts C1 or C5 were prepared with organopolysiloxanes A and B according to Example 2 (Pt metal concentration of 10 ppm).

[0111]

[0132] The stability of the solutions was then determined.

[0133] Solutions containing Pt(octane-2,4-dione)2 (C1) remained stable for more than 20 days protected from light and for more than 7 hours exposed to ambient light.

[0112]

[0134] The solution containing the mixture of Pt Karstedt-benzoquinone complexes (C5) is crosslinked in a final step of 5 min protected from light.

[0135] These results show that the silicone composition according to the invention has a very good stability without irradiation: in fact, the gel time without irradiation is very long, significantly longer than that obtained with the mixture of Pt Karstedt-benzoquinone complexes (C5).

Claims

1. a. Silicon-bonded C ２ ~C １２ At least one organopolysiloxane A having at least two alkenyl groups per molecule therein; b. at least one organopolysiloxane B having at least two SiH units per molecule; c. a catalytically effective amount of at least one Pt(octane-2,4-dione) ２ and a hydrosilylation catalyst C, 1. A radiation crosslinkable silicone composition X comprising:

2. Pt(octane-2,4-dione) ２ Cis and trans diastereomers 【Chemistry 1】 cis, 【Chemistry 2】 Trans 2. The silicone composition of claim 1, which is a mixture of

3. 3. Silicone composition X according to claim 1 or 2, which is crosslinkable by exposure to radiation having a wavelength comprised between 100 nm and 450 nm, in particular UV radiation.

4. Silicone composition X according to one of claims 1 to 3, wherein the amount by weight of catalyst C, calculated by the weight of metallic platinum, is generally comprised between 1 and 400 ppm, preferably between 2 and 200 ppm, and more preferably between 5 and 100 ppm, based on the total weight of said silicone composition X.

5. 1. A method for the preparation of a coating on a substrate, comprising the steps of: - application of a silicone composition X according to any one of claims 1 to 4 to a substrate, preferably a textile substrate; - a step of crosslinking of said composition by electron or photon irradiation, preferably by exposure to electron beams, by exposure to gamma radiation or by exposure to radiation having a wavelength comprised between 100 nm and 450 nm, preferably UV radiation; The method includes:

6. The method of claim 5, wherein the crosslinking occurs by exposure to UV radiation, the source of which is a UV-LED lamp.

7. A coated support obtainable according to the process according to claim 5 or 6.

8. Use of a silicone composition X according to any one of claims 1 to 4 for the preparation of a silicone elastomer.

9. Pt(octane-2,4-dione) for hydrosilylation ２ Use as a catalyst.

10. - C bonded to silicon ２ ~C １２ At least one organopolysiloxane A having at least two alkenyl groups per molecule therein; at least one Pt(octane-2,4-dione) ２ and a hydrosilylation catalyst C, 1. A premix for a silicone composition comprising:

Images