KR20060102344A - Silicon composition and useful method for increasing the friction coefficient of an airbag for the protection of the occupant of a vehicle - Google Patents

Abstract

The invention relates to the general field of airbags. The invention more specifically relates to a method and composition enabling the friction of coated fabrics which are used in airbags to be increased by using a silicon composition comprising an additive made up of particles of a resin (III) comprising at least one (co)polyamide. After the composition has been coated on the fabric media and cross-linking has occurred, the coated media have optimum friction coefficient properties.

Description

SILICON COMPOSITION AND USEFUL METHOD FOR INCREASING THE FRICTION COEFFICIENT OF AN AIRBAG FOR THE PROTECTION OF THE OCCUPANT OF A VEHICLE}

The overall field of the present invention is in the field of silicone coating compositions, in particular two-pack or multi-pack type silicone coating compositions which can be cured by polyaddition or hydrosilylation reactions to produce elastomers in thin layers. Such curable compositions are used, in particular, as coatings for the protection or physical reinforcement of various textile substrates, for example fibers, wovens, braids or nonwoven supports.

Such silicone coatings are generally obtained by coating the substrate and then curing by polyadding the unsaturated group of the polyorganosiloxane (alkenyl, for example Si-Vi) to the hydrogen of the same or another polyorganosiloxane. Lose.

Currently, many cars are equipped with acceleration sensors that measure the deceleration of the car. If the reference deceleration value is exceeded, explosive pellets cause combustion of flammable solids following the combustion of supplemental ammunition; This solid is converted to gas (eg nitrogen) and causes the cushion to swell. For further details relating to such anti-protective bags, ie "airbags", reference may be made in particular to French patent FR-A-2 668 106.

Historically, such bags are formed by a network of synthetic fibers, for example polyamides, at least one side of which is coated with an elastomeric layer, such as chloroprene. Air bags (or inflatable cushions) are air-filled bags made of pleated, tightly sewn polyamide fabric. Since chloroprene has not been found to meet all of the above objectives, the silicone composition easily replaces chloroprene in the present application.

As such, these silicone compositions are used principally in the coating of flexible—weave, braided or nonwoven—materials, which are also used to make refurbishment protective bags for automobile occupants, also known as "airbags."

The present invention therefore relates to the use of silicones for the production of such protective bags.

The front airbag may deploy to or adapt to the impact force. These can be supplemented with side airbags and curtains. Such protective coatings or layers exist due to the fact that the gases liberated in the gas generator in the event of an impact are extremely hot and contain incandescent particles that can damage the Nylon ^® bags.

Thus, the elastomeric protective layer therein must be particularly resistant to high temperatures and physical forces. It is also important that this elastomeric membrane is in the form of a thin, uniform film that is completely adhered to the synthetic fabric support forming the walls of the airbag. However, when the silicon precipitate increases, an increase in the friction coefficient, that is, a decrease in the slip characteristic of the airbag is observed. In addition, if the silicon layer is on the outer surface of the airbag, this ensures the bag's leak tightness after the bag is deployed and inflated.

Apart from this, these inflatable bags must be made from fabrics having good slip properties and good coefficients of friction so that the development of the bags is not delayed and at the same time without jeopardizing the rest of the expected properties, or even these, in particular fire resistant, heat resistant, Strengthen durability and wear resistance ("rubbing test"), tear strength and combing strength. This good slipping property is also necessary to improve the passive positioning of the airbag under the zone marker during manufacturing, in particular during sewing and reinforcement operations around the generator periphery. Better slipping properties also allow to reduce the risk of injury to the passenger's face.

Prior art EP-A-0 533 840 and US-5 296 298 describe silicone compositions for airbag applications. According to EP-A-0 553 840, such known silicone compositions comprise:

(A) a polydiorganosiloxane comprising at least two alkenyl groups per molecule,

(B) a polyorganohydrogenosiloxane comprising at least two hydrogen atoms bonded to silicon in each molecule,

(C) a metallic catalyst of the platinum group,

(D) an adhesion promoter consisting of an epoxy-functional organosilicon compound,

(E) an inorganic filler whose weight is proportional to the amount of polyorganosiloxane (A),

(F) a polyorganosiloxane resin, and optionally

(G) compounds useful as cure inhibitors.

However, the reference only shows a method of obtaining a homogeneous adhesive film for the airbag coating, and there is no word on solving the aforementioned problem.

According to US-5 296 298, such silicone compositions comprise:

(A) a polydiorganosiloxane comprising at least two alkenyl groups per molecule,

(B) a polyorganohydrogenosiloxane comprising at least two hydrogen atoms bonded to silicon in each molecule,

(C) silanes containing methacrylic functional groups,

(D) epoxyalkoxysilanes,

(E) aluminum chelate, and

(F) a metallic catalyst of the platinum group.

The reference merely provides a method for obtaining a silicone film showing good adhesion to the airbag support. Such compositions do not meet the new expectations of airbag manufacturers with regard to the control of the airbag's slip characteristics.

Document EP-A-0 681 014 can be used in particular as an airbag lining, and for this purpose, in particular, it has good properties in terms of fire resistance and heat resistance, physical properties, aging behavior, adhesion and surface uniformity, and adhesion to textile substrates. This particularly more preferred silicone composition is described. The solution proposed by the invention consists of using the following:

A silicone coating composition consisting of a mixture formed from:

(1) one or more polyorganosiloxanes comprising at least two C2-C6 alkenyl groups bonded to silicon, per molecule

(2) one or more polyorganosiloxanes containing two or more hydrogen atoms bonded to silicon per molecule,

(3) a catalytically effective amount of at least one catalyst, consisting of a metal belonging to a platinum group,

(4) adhesion promoter,

(5) optionally, an inorganic filler,

(6) optionally, one or more curing inhibitors, and

(7) optionally, at least one polyorganosiloxane resin,

In this composition, the adhesion promoter consists only of a combination of three or more of the following components:

(4-1) one or more alkoxylated organosiloxanes, including one or more C2-C6 alkenyl groups, per molecule,

(4-2) at least one organosilicon compound comprising at least one epoxy radical, and

(4-3) at least one metal chelate M and / or the formula M (OJ) n (n is the valence of M, J is a linear or branched C1-C8 alkyl, M is Ti, Zr, Ge, Li, Metal alkoxide selected from the group consisting of Mn, Fe, Al and Mg.

Such formulations have the disadvantage that the resulting elastomers can have a somewhat gross feeling, which, in addition to the unpleasant hand, can be detrimental to the physical appearance and properties of the coated support. In the field of inflatable bags for protecting vehicle occupants, improvement would be particularly desirable if the deployment of the bag depends in particular on the coefficient of friction coefficient.

Therefore, these compositions do not comply with the new expectations of airbag manufacturers in terms of controlling the slippery properties of airbags.

French Patent 2 765 884 describes silicone compositions as mixtures, including:

(1) at least one polyorganosiloxane containing at least two C2-C6 alkenyl groups linked to silicon per molecule,

(2) one or more polyorganosiloxanes containing two or more hydrogen atoms linked to silicon per molecule,

(3) at least one catalytically effective amount of at least one metal belonging to the platinum group,

(4) adhesion promoter,

(5) optionally, a reinforcement system, which may be at least one polyorganosiloxane resin and / or at least one reinforcing filler,

(6) optionally, one or more curing inhibitors, and

(7) organic or inorganic cavity microspheres.

These expandable organic microspheres include polymer walls containing liquids or gases. The expansion of these microspheres is caused by heating the polymer above the softening point and heating the liquid to a temperature sufficient to evaporate the liquid or to adequately expand a gas, which may be, for example, an alkane such as isobutane or isopentane. The polymers used for their walls are made from vinyl chloride, vinylidene chloride, acrylonitrile, methyl methacrylate or styrene monomers or from acrylonitrile / methacrylonitrile or acrylonitrile / vinylidene chloride copolymers.

However, the product obtained by this type of composition after curing is a foam having insufficient mechanical properties (eg combing strength). In other words, it is desirable to find an alternative to this type of composition.

The present invention is directed to overcoming the drawbacks of the prior art.

In this respect, one of the essential objects of the present invention is to provide a method of improving the coefficient of friction of a woven, braided or nonwoven fibrous support. These supports treated with the process according to the invention are particularly useful for use in the field of inflatable safety bags or airbags for vehicles.

The second object of the present invention is particularly useful for applications in the field of inflatable safety bags or airbags for vehicles, and after curing and coating on the cloth, it has an optimum property relating to slip, ie a good coefficient of friction, polyaddition or free It is to provide a silicone coating composition that can be cured by a radical reaction.

It is a third object of the present invention to provide a curable silicone coating composition for an air bag that is easy to use and apply and is economical.

The end object is to provide a woven, braided or nonwoven fibrous support in which one or two sides are coated with the silicone elastomer according to the invention, which is particularly useful in the field of airbags.

More specifically, the invention in the first subject relates to a method of improving the coefficient of friction of a woven, braided or nonwoven fibrous support comprising the following steps:

a) preparing a curable silicone coating composition (A) comprising:

(1) component (a-1) or (a-2):

(A-1) corresponding to one or more polyorganosiloxanes that can be cured by the action of a catalyst based on one or more organic peroxides, and

(A-2) corresponding to a polyorganosiloxane blend that can be cured by polyaddition, comprising:

At least one polyorganosiloxane (I) containing at least two C2-C6 alkenyl groups linked to silicon per molecule, and

At least one polyorganosiloxane (II) containing at least two hydrogen atoms linked to silicon per molecule,

(2) An effective amount of a curing catalyst consisting of: one or more organic peroxides when using (a-1), and one or more metals (or compounds) of the platinum group when using (a-2) ),

(3) particles of at least one resin (III) comprising at least one (co) polyamide,

(4) optionally, one or more reinforced fillers,

(5) one or more adhesion promoters (IV),

(6) an additive system (B), optionally consisting of the following mixtures, to which the constituents are added sequentially or simultaneously:

At least one polyorganosiloxane resin (V), optionally mixed with at least one polyorganosiloxane, which is present in an amount of up to 60% by weight relative to the total weight of the mixture, and

Calcium carbonate (CaCO ₃ ) present in up to 30% by weight relative to the total weight of the mixture;

(7) optionally, at least one curing inhibitor (VI),

b) applying the silicone coating composition (A) prepared in step a) at least 10 g / m 2 for one or two sides of the woven, braided or nonwoven fibrous support, and

c) curing the precipitate formed in step b) by heating to a temperature which may be up to 210 ° C., electromagnetic radiation, in particular infrared, to form an elastomer.

The presence of particles of resin (III) comprising one or more (co) polyamides has the effect of increasing the coarseness of the coating, thereby reducing the coefficient of friction without degrading the mechanical properties of the fabric.

Preferably, the particles of resin (III) are polyamide-6, polyamide-6.6, polyamide-4, polyamide-11, polyamide-12, polyamide 4-6, 6-10, 6-12, 6-36 and 12-12, and one or more (co) polyamides selected from the group consisting of copolymers and mixtures thereof.

According to one preferred embodiment, the particles of resin (III) comprise polyamide-12.

In another preferred manner, the particles of resin (III) are spherical.

The average diameter of the (co) polyamide particles will preferably be from 5 to 100 μm, in particular from 10 to 50 μm.

These particles are preferably present in a proportion of up to 40% by weight, preferably from 1 to 30% by weight and even more preferably from 5 to 20% by weight relative to the total weight of the mixture.

Polyorganosiloxanes (a1) that can be cured by the action of a catalyst based on one or more organic peroxides are advantageously products containing siloxane units of the formula:

[In meals:

Symbol R ^1, which may be the same or different, represents a hydrocarbon-based group having 1 to 12 carbon atoms, preferably 1 to 8 carbon atoms, optionally substituted;

a is 1, 2 or 3;

Preferably, the symbol R ¹ is selected from:

Methyl, ethyl, propyl, butyl, hexyl and dodecyl groups,

Cycloalkyl groups, for example cyclohexyl,

Alkenyl groups, for example vinyl, allyl, butenyl and hexenyl groups,

Aryl groups such as phenyl, tolyl and aralkyl groups such as β-phenylpropyl, and

The aforementioned groups, wherein at least one hydrogen atom is replaced with at least one halogen atom, cyano group or cyano group equivalent, for example chloromethyl, trifluoropropyl or cyanoethyl.

Even more preferably, the polyorganosiloxane (a-1) is terminated with trimethylsilyl, dimethylvinyl, dimethylhydroxysilyl or trivinylsilyl units at the chain ends.

In one particularly advantageous embodiment, the polyorganosiloxane (a-1) contains at least two alkenyl groups per molecule.

Among the organic peroxides that can be used according to the invention, benzoyl peroxide, bis (p-chlorobenzoyl) peroxide, bis (2,4-dichlorobenzoyl) peroxide, dicumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, t-butyl perbenzoate, t-butylcumyl peroxide, halogenated derivatives of the aforementioned peroxides, for example bis (2,4 -Dichlorobenzoyl) peroxide, 1,6-bis (p-toluoyl-peroxycarbonyloxy) hexane, 1,6-bis (benzoylperoxycarbonyloxy) hexane, 1,6-bis (p-tolu) Mention may be made of oil-peroxycarbonyloxy) butane and 1,6-bis (2,4-dimethylbenzoylperoxycarbonyloxy) hexane.

The polyorganosiloxane (I) of the silicone coating composition (A) used in the curing mode by the polyaddition reaction includes:

(i) siloxane units of the formula:

[here:

The symbol R ¹ represents an alkenyl group, preferably vinyl or allyl,

The symbol Z, which may be identical or different, each represents a monovalent hydrocarbon-based group having no adverse action on the activity of the catalyst and is selected from alkyl groups having 1 to 8 carbon atoms optionally substituted with one or more halogen atoms, and aryl groups,

a is 1 or 2, b is 0, 1 or 2, and the sum of a + b is equal to 1, 2 or 3), and any

(ii) other siloxane units of the formula:

(here,

Z has the same meaning as above and c is 0, 1, 2 or 3;

The viscosity of the polyorganosiloxane (I) may be at least 200 mPa · s, preferably less than 200,000 mPa · s.

All viscosities contemplated herein are known methods and essentially correspond to the dynamic viscosity magnitude measured at 25 ° C.

Polyorganosiloxane (I) may be formed solely from units of formula (I-1) or may contain units of formula (I-2). Similarly, it may have a linear, branched, annular or networked structure. Z is generally selected from methyl, ethyl and phenyl radicals and at least 60 mole% (or numerical aspect) of the radicals Z are methyl radicals. Examples of siloxane units of formula (I-1) are vinyldimethylsiloxane, vinylphenylmethylsiloxane, vinylmethylsiloxane and vinylsiloxane units.

Examples of siloxyl units of formula (I-2) is a SiO _4/2 units, dimethyl siloxyl, phenyl siloxyl, diphenyl siloxyl, siloxyl and methyl phenyl siloxane chamber. Examples of polyorganosiloxanes (I) are linear and cyclic compounds such as: dimethylvinylsilyl end group-containing dimethylpolysiloxane, trimethylsilyl end group-containing (methylvinyl) (dimethyl) polysiloxane copolymer, dimethylvinylsilyl end group-containing (Methylvinyl) (dimethyl) polysiloxane copolymer and cyclic methylvinylpolysiloxane.

Advantageously, the polyorganosiloxane (II) contains siloxane units of the formula:

[here:

L groups can be the same or different and each has no adverse action on the activity of the catalyst, preferably an alkyl group having 1 to 8 carbon atoms, optionally substituted with one or more halogen atoms, advantageously methyl, ethyl, propyl and 3 , 3,3-trifluoropropyl group, and an aryl group, advantageously a monovalent hydrocarbon-based group selected from xylyl, tolyl or phenyl radicals,

d is 1 or 2, e is O, 1 or 2, and the sum of d + e is equal to 1, 2 or 3,

Optionally, at least some of the other units are units of the following average formula:

(Wherein the L group has the same meaning as described above and g is equal to 0, 1, 2 or 3).

The dynamic viscosity of the polyorganosiloxane (II) is at least 10 mPa · s, preferably 20 to 1000 mPa · s. The polyorganosiloxane (II) may be formed solely from units of formula (II-1) or may contain units of formula (II-2). The polyorganosiloxane (II) may have a linear, branched, cyclic or networked structure. The L group has the same meaning as in the Z group. Examples of units of formula (II-1) is _{H (CH 3) 2 Si0 1/2} , HCH 3 SiO 2/2 , and _{H (C 6 H 5) SiO} 2/2.

Examples of units of formula (II-2) are the same as given above for units of formula (I-2).

Examples of polyorganosiloxanes (II) are linear and cyclic compounds, for example:

Dimethylpolysiloxanes containing hydrogenodimethylsilyl end groups,

A copolymer comprising a (dimethyl) (hydrogenomethyl) polysiloxane unit containing a trimethylsilyl end group,

A copolymer comprising a (dimethyl) (hydrogenomethyl) polysiloxane unit containing a hydrogenodimethylsilyl end group,

Hydrogenomethylpolysiloxanes containing trimethylsilyl end groups,

Cyclic hydrogenomethylpolysiloxanes.

Compound (II) may optionally be a mixture of dimethylpolysiloxanes containing hydrogenodimethylsilyl end groups and polyorganosiloxanes containing three or more hydrogenosiloxane groups.

The ratio of the number of hydrogen atoms linked to the silicon of the polyorganosiloxane (II) to the total number of groups containing the alkenyl unsaturation of the polyorganosiloxane (I) is 0.4 to 10, preferably 0.6 to 5.

The base of the silicone polyaddition composition is based only on linear polyorganosiloxanes (I) and (II), such as described in patents: US-A-3 220 972, US-A-3 697 473 and US-A-4 340 709. Or branched or networked polyorganosiloxanes (I) and (II), such as those described in, for example, US Pat. Nos. 3,384,406 and 434 366.

According to one specific embodiment, the following is used:

-Formed from units of formula (I-2), wherein c = 2, each end comprising a chain blocked with formula (I-1), wherein a = 1 and b = 2 At least one linear polyorganosiloxane (I), and

At least one linear polyorganosiloxane (II) containing at least three hydrogen atoms linked to silicon in the structure and / or at the chain ends in the structure:

More specifically than:

At least one chain formed from units of formula (I-2), wherein c = 2, each terminal blocked with formula (I-1), wherein a = 1 and b = 2 Linear polyorganosiloxane (I), and

-From units of formula (II-1), wherein d = 1 and e = 1 and any units of formula (II-2), where g = 2, each end of which is represented by formula (II- 1) at least one linear polyorganosiloxane (I) comprising a chain blocked in units of d = 1 and e = 2.

When (a-2) is used, the curing catalyst consists of at least one platinum group metal (or compound) which is also known. The metals of the platinum group are known under the name of platinum, which includes ruthenium, rhodium, palladium, osmium and iridium in addition to platinum. Platinum and rhodium compounds are preferably used. Patents US-A-3 159 601, US-A-3 159 602, US-A-3 220 972 and European Patents EP-A-0 057 459, EP-A-0 188 978 and EP-A-0 190 530 Complexes of the platinum and organic products described, and the platinum and vinylorganosiloxanes described in patents US-A-3 419 593, US-A-3 715 334, US-A-3 377 432 and US-A-3 814 730 Complexes of may be used in particular. Generally the preferred catalyst is platinum. In this case, the weight of the catalyst (III), calculated by the weight of the platinum metal, is generally from 2 to 40 000 ppm, preferably from 5 to 200, based on the total weight of the polyorganosiloxanes (I) and (II). ppm.

Due to the presence of the additive system (B) in the silicone coating composition (A) according to the invention, it is possible to control the coaming strength and tearing strength of the woven, braided or nonwoven fibrous support. Calcium carbonate does not need to undergo a compatibilization treatment (by heating or surface treatment) in order to be used in the system (B) and thus cannot be compared to a simple semi-reinforced filler.

Resin (V) preferably comprises at least one alkenyl residue in its structure. According to one preferred method, the polyorganosiloxane resin (V) contains a siloxyl units Q of the formula SiO _4/2.

According to another specific manner, the polyorganosiloxane resin (V) contains from 0.1 to 20% by weight of alkenyl group (s), preferably more than 4% by weight of alkenyl group (s), in the structure, Siloxane units of type M, which may be the same or different, siloxane units of type T, and / or Q, which may be the same or different and siloxane units of any type D.

In a particularly preferred method, the polyorganosiloxane resin (V) comprises at least 2% by weight, preferably at least 5% by weight of siloxane units of type Q.

Such resins (V) are well known and are commercially available branched organopolysiloxane oligomers or polymers. These are in the form of solutions, preferably siloxane solutions. They have the general formula R ₃ SiO _0.5 (unit M), R ₂ SiO (unit D), RSiO _{1 .5} (unit T) and at least two different units selected from those of SiO ₂ (unit Q) in its structure, At least one of the units is a unit T or Q.

The radicals R are the same or different and are selected from linear or branched C 1 -C 6 alkyl radicals, C 2 -C 4 alkenyl radicals, phenyl, 3,3,3-trifluoropropyl and hydroxy groups. As the alkyl radical R, for example methyl, ethyl, isopropyl, tert-butyl and n-hexyl radicals can be mentioned, and as alkenyl radicals R can be mentioned vinyl radicals.

It is to be understood that some of the radicals R in the above-mentioned type of resins (V) are alkenyl radicals.

As examples of branched organosiloxane oligomers or polymers, mention may be made of resin MQ, resin MDQ, resin TD and resin MDT, wherein the alkenyl functionality may be retained by units M, D and / or T. As an example of a particularly suitable resin, mention may be made of vinyl MDQ resins having a weight content in which the content of vinyl groups is from 0.2% by weight to 10% by weight.

When the curable silicone coating composition (A) according to the invention contains a reinforcing filler, it may be silica having a BET specific surface area of at least 50 m 2 / g. The filler is advantageously processed by treating with various organosilicon compounds commonly used for this purpose. Thus, the organosilicon compounds can be selected from the group consisting of organochlorosilane, diorganocyclopolysiloxane, hexaorganodisiloxane, hexaorganodisilazane or diorganocyclopolysilazane (French Patent FR-A-1 126 884, FR-A -1 136 885 and FR-A-1 236 505 and British Patent GB-A-1 024 234).

The curable silicone coating composition (A) according to the invention may also comprise standard heavy reinforcing or packing fillers, for example diatomaceous earth or ground quartz.

Other non-silicate minerals may include the following as heavy reinforcing or packing fillers: carbon black, titanium dioxide, aluminum oxide, hydrogenated alumina, expanded vermiculite, unexpanded vermiculite, calcium carbonate treated with compatibilization, zinc oxide , Mica, talc, iron oxide, barium sulfate, hydrated lime etc.

The fillers are based on the composition as a whole at a rate of 5% to 30%, preferably 15% to 25%, for reinforcing fillers, 5% to 40%, preferably 10% for heavy reinforcing or packing fillers. To 30%.

Without being limited to this, it is contemplated that the adhesion promoter (IV) only contains:

(IV.1) at least one alkoxy organosilane comprising at least one C2-C6 alkenyl group per molecule,

(IV.2) at least one organosilicon compound comprising at least one epoxy radical, and

(IV.3) at least one metal chelate M and / or the formula M (OJ) n, wherein n is the valence of M, J is a linear or branched C1-C8 alkyl, and M is Ti, Zr, Ge , Li, Mn, Fe, Al and Mg).

According to one preferred arrangement of the invention, the alkoxy organosilane (IV.1) of the promoter (IV) is selected from products having the general formula:

[In the meal,

R 1, R 2 and R 3 are the same or different, hydrogenated or hydrocarbon-based radicals and represent phenyl optionally substituted with hydrogen, linear or branched C 1 -C 4 alkyl or one or more C 1 -C 3 alkyl,

U is a linear or branched C1-C4 alkylene,

-W is a bond

R 4 and R 5 are homologous or different radicals, linear or branched C 1 -C 4 alkyl radicals,

x '= 0 or 1,

-x = 0 to 2;

Although not limited to this, it is contemplated that vinyltrimethoxysilane is a particularly suitable compound (IV.1).

For organosilicon compounds (IV.2) it is expected according to the invention to be selected from:

a) product (IV.2a) corresponding to the formula:

[In meals:

R6 is a linear or branched C1-C4 alkyl radical,

R7 is a linear or branched alkyl radical.

-y is 0, 1, 2 or 3,

X is defined by the formula:

here,

E and D are homologous or different radicals selected from linear or branched C1-C4 alkyl,

-z is 0 or 1,

R 8, R 9 and R 10 are homologous or different radicals representing hydrogen or linear or branched C 1 -C 4 alkyl.

R 8 and R 9 or R 10 may alternatively constitute a 5- to 7-membered alkyl ring with two carbon atoms comprising an epoxy],

b) or a product (IV.2b) consisting of an epoxy functional polydiorganosiloxane comprising:

(i) at least one siloxane unit of formula

[In the meal,

X is a radical as defined above as formula (IV.2a),

G is a monovalent hydrocarbon group selected from alkyl and aryl groups having 1 to 8 carbon atoms optionally substituted with at least one halogen atom, having no undesirable action on the activity of the catalyst,

p = 1 or 2,

q = 0, 1 or 2,

-p + q = 1, 2 or 3; and

(2i) optionally one or more siloxane units of the formula:

[Wherein, formula G has the same meaning as above and r is 0, 1, 2 or 3].

For the final compound (IV.3) of the adhesion promoter of the silicone composition (EVF) according to the invention, the preferred product is one in which the metal M and / or alkoxide (IV.3) of the chelate is selected from the following list: Ti , Zr, Ge, Li or Mn. It should be pointed out that titanium is more particularly preferred. It may be combined with an alkoxy radical such as, for example, butoxy.

Adhesion promoters (IV) may be formed by:

-(IV.1) alone

-(IV.2) alone

-(IV.1) + (IV.2)

According to two preferred embodiments:

-(IV.1) × (IV.3)

-(IV.2) × (IV.3)

Finally, according to the most preferred embodiment: (IV.1) + (IV.2) + (IV.3).

According to the invention, advantageous combinations for the formation of the adhesion promoter are as follows:

Vinyltrimethoxysilane (VTMO), representative of formula (IV.1),

3-glycidoxypropyltrimethoxysilane (GLYMO), representative of formula (IV.2), and

Butyl titanate, which is a representative example of formula (IV.3).

In quantitative terms, the weight ratio (expressed in weight percent to the sum of these three) between (IV.1), (IV.2) and (IV.3) can be expressed as:

(IV.1)> 10, preferably 15 to 70, even more preferably 25 to 65,

(IV.2) ≤ 90, preferably 70 to 15, even more preferably 65 to 25, and

(IV.3)> 1, preferably 5 to 25, even more preferably 8 to 18,

It should be understood that the sum of these ratios in (IV.1), (IV.2) and (IV.3) should equal 100%.

For better adhesion properties, the weight ratio (IV.2) :( IV.1) is preferably 2: 1 and 0.5: 1, with a 1: 1 ratio being more particularly preferred.

Advantageously, the adhesion promoter (IV) is present in a proportion of 0.1% to 10%, preferably 0.5% to 5%, even more preferably 1% to 3% with respect to all the constituents of the curable silicone coating composition (A). exist.

According to one preferred embodiment, the curable silicone coating composition (A) for use in the process according to the invention comprises a mixture formed of:

(1) one or more polyorganosiloxanes (I) containing at least two C2-C6 alkenyl groups linked to silicon per molecule,

(2) one or more polyorganosiloxanes (II) containing at least two hydrogen atoms linked to silicon per molecule,

(3) Catalytically effective amount of one or more catalysts (III), consisting of one or more metals belonging to the platinum group

(4) one or more adhesion promoters (IV),

(5) particles of at least one resin (III) containing at least one (co) polyamide,

(6) an additive system consisting of the following mixtures, the constructs of which are added sequentially or simultaneously:

At least one polyorganosiloxane resin (V), which is present at up to 60% by weight relative to the total weight of the mixture, and optionally mixed with at least one polyorganosiloxane that acts as a diluent, and

Calcium carbonate (CaCO ₃ ) present in up to 30% by weight relative to the total weight of the mixture;

(7) optionally, one or more reinforced fillers,

(8) optionally, at least one curing inhibitor (VI),

(9) optionally, at least one coloring additive (iv),

(10) optionally, at least one additive for improving fire resistance.

Curing inhibitors (VI) can be selected from the following compounds:

Polyorganosiloxanes substituted with one or more alkenyls, which may optionally be in cyclic form, particularly preferably tetramethylvinyltetrasiloxane,

-Pyridine,

Organic phosphines and phosphites,

Unsaturated amides,

Alkyl maleates, and

Acetylene alcohols.

Such acetylenic alcohols (see FR-B-1 528 464 and FR-A-2 372 874), belonging to the preferred hydrosilylation reaction thermal blockers, have the formula:

[In meals:

R 'is a linear or branched alkyl radical or a phenyl radical;

R ″ is H or a linear or branched alkyl radical or phenyl radical; the radicals R ′ and R ″, and the carbon atom α for the triple bond may form a ring;

The total number of carbon atoms contained in R 'and R "is at least 5, preferably 9-20.

Examples of such alcohols that may be mentioned may include:

1-ethynyl-1-cyclohexanol;

3-methyl-1-dodecin-3-ol;

3,7,11-trimethyl-1-dodecin-3-ol;

1,1-diphenyl-2-propyn-1-ol;

3-ethyl-6-ethyl-1-nonin-3-ol;

2-methyl-3-butyn-2-ol;

3-methyl-1-pentadecin-3-ol;

Diallyl maleate or diallyl maleate derivative.

Such α-acetylene alcohols are commercially available products.

Such inhibitor (VI) is present in a proportion of up to 3000 ppm and preferably in a proportion of 100 to 1000 ppm relative to the total weight of organopolysiloxanes (I) and (II).

Examples that may be referred to as additives (iii) for improving fire resistance include compounds containing phenyl groups substituted with amino (secondary or tertiary) groups. Examples of such additives can be found in reference US 5 516 938. Useful amounts of such additives are generally from 0.01 to 1 parts by weight, based on the total amount of the composition.

In a known manner, the curable silicone coating composition (A) according to the invention can be supplemented with various conventional additives, for example dyes.

The invention also relates to the curable silicone composition (A) according to the invention and used in the process described above.

According to another aspect, the present invention relates to a two-pack or multi-pack precursor system (C) for the curable silicone coating composition (A) described above. Such precursor systems include two or more separate A and B moieties that are mixed together to form a composition, one of which A or B moieties being a catalyst and only one polyorganosiloxane species (I) or It contains (II).

When accelerator systems (IV-1), (IV-2) and (IV-3) are used, another feature of this precursor system is that it can be incorporated into its A or B portion containing polyorganosiloxane species (II). There is no compound (IV-3) of the promoter (IV), and its A or B portion comprising the compound (IV-1) of the promoter (IV) does not contain a catalyst (III).

The viscosity of the A and B moieties and their mutual mixtures can be adjusted by varying the amount of construct and by selecting polyorganosiloxanes having different viscosities.

The A and B portions, once mixed together, form a ready-to-use silicone composition, which can be applied to the support by any suitable coating means (eg, doctor blade or roll). After curing, it is generally aimed that the final precipitated thickness is between 25 and 300 μm, in particular between 50 and 200 μm. It is not necessary to have a uniform thickness, because if the surface of the support is uneven, uneven deposition is caused.

The composition according to the invention is thermoset and / or cured by electromagnetic radiation (radiation of accelerated electrons or "electron beams").

The composition according to the invention covers a flexible support, in particular a woven, braided or nonwoven fiber weave, and preferably a woven, braided or nonwoven support made of synthetic fibers, advantageously a support made of polyester or polyamide Or to coat.

The invention also relates to a woven, braided or nonwoven fibrous support, wherein one or both sides are coated with an elastomer which can be obtained by:

a)-a composition of the above-described silicone coating composition (A), or a mixture of A and B portions of the two-pack or multi-pack system (B) described above, into a woven, braided or nonwoven fibrous support Or applying at least 10 g / m ² on two sides, and

  Curing the precipitate formed in the preceding step by heating, electromagnetic radiation, or infrared radiation to a temperature which may be up to 210 ° C., to form an elastomer,

or

b) the method according to the invention described above.

Another aspect of the invention relates to a pneumatic bag for the protection of an automobile occupant formed from a support coated according to the procedure of the invention described above.

The invention also relates to the use of two-pack or multi-pack systems (B) according to the invention and curable silicone coating compositions (A) according to the invention for coating woven, braided or nonwoven fibrous supports. Preferably, this support is designed for the formation of a pneumatic bag for the protection of the motor vehicle occupant. In one preferred embodiment, the support is a fabric having an open tissue having a porosity of greater than 10 l / dm ² / min according to ISO standard 9237.

Covering or coating at least one side of a flexible support material, in particular textiles (eg polyamide fabrics), such as pneumatic bags, tent nets, parachutes, etc., to protect vehicle occupants in the event of an impact, for example It is particularly useful for the manufacture of technical fabrics.

In this respect, it has been found that the compositions or methods according to the invention are particularly noteworthy for coating supports with open tissue as well as for coating supports commonly used in the manufacture of puffed bags. The term "support with open tissue" means a support having a porosity of greater than 10 l / dm ² / min according to ISO standard 9237. In the case of fabrics, the open tissue corresponds in particular to the number of warps and wefts per centimeter and is defined as the sum of 36 or less.

As particularly recommended fabrics in the context of the present invention, fabrics with uncoated weights below 200 g / m ² , in particular below 160 g / m ² will generally be mentioned. Thus, such fabrics, in particular polyamide fabrics of 16 x 16 to 18 x 18 yarns / cm, may be mentioned, for example 470 dtex (decitex) fabrics having this feature.

In order to impart certain properties or reinforced properties as a function of the application of coated supports or fabrics, technical textile fibers, ie textiles having improved properties, for example increased fastness, compared to standard fibers It can be pointed out that substrates formed from fibers, in particular textiles, can also be used.

Accordingly, the subject of the invention is also such a flexible support, in particular a textile support which can be coated according to the invention, which can have the characteristics and properties indicated above.

Due to the characteristics and properties indicated above, the air injectable bags for the protection of the occupants of the motor vehicle, once coated, have a good coefficient of friction, good coaming strength and tear strength, furthermore optimum properties, especially impermeability, thermal protection, porosity, It can be produced from open tissue fabrics, in particular polyamide or polyester fabrics, as described above, with optimum properties in terms of flexibility and fire resistance. This enables the production of pneumatic bags that are more economical and have a better performance quality than bags made from coated fabrics of the prior art. Thus, for equivalent weights, it is possible to increase the thickness of the coating without deteriorating the coefficient of friction. In general, the coatings contemplated herein may correspond to the precipitation of a single layer on one or more sides of the flexible support material (primary coating). However, in order to have the desired total thickness which ensures the highest possible quality of performance in terms of impermeability and good feel properties, precipitation of the second layer or optionally the third layer on one or more sides of the already coated support material can also be considered. (Secondary coating).

The following examples regarding the preparation of the compositions according to the process of the invention and their application as coatings for polyamide fabrics will make the invention clearer and highlight its advantages and modified implementations. The quality of performance of the products produced from the process according to the invention will be explained by comparative tests.

In this example, the viscosity was measured using a Brookfield viscometer in accordance with the instructions of AFNOR standard NFT-76-106, May 1982.

Example 1:

1) Definition of constructs:

Polyorganosiloxane (I): a polyvinyl chloride having a viscosity of 100 000 mPa.s, containing 0.003 Si-Vi functional groups per 100 g of oil and blocking each end of the chain with (CH ₃ ) ₂ ViSiO _0.5 units Dimethylsiloxane oils [hereafter referred to as oil (I)];

Polyorganosiloxane, hereinafter referred to as diluent (A): a polydimethylsiloxane oil having a viscosity of 60 000 mPa · s and blocked at each end of the chain with (CH ₃ ) ₂ ViSiO _0.5 units;

Polyorganosiloxane (II): having a viscosity of 25 mPa.s and containing a total of 0.7 Si-H functionalities per 100 g of oil (including 0.6 Si-H functionalities located in the chain), (CH ₃ ) ₂ HSiO poly (dimethyl) (hydrogenomethyl) siloxane oils blocked at each end of the chain in _0.5 units [hereafter referred to as oil (II)];

Catalyst: platinum metal introduced in the form of an organometallic complex containing 10% by weight of platinum metal known under the name Karstedt catalyst (hereafter referred to as catalyst);

Ethynylcyclohexanol 1 (ECH inhibitor);

Adhesion promoter (IV): mixture consisting of:

(IV-1) vinyltrimethoxysilane (VTMO)

(IV-2) glycidoxypropyltrimethoxysilane (GLYMO), and

(IV-3) butyl titanate Ti (OBu) ₄ (TBT);

Resin (V): 0.8 weight percent vinyl group (Vi) and 27 weight percent _0.5 (CH ₃ ) ₃ SiO _0.5 units, 0.15 weight percent (CH ₃ ) ₂ ViSiO _0.5 units, 60 weight percent (CH ₃ ) a polyorganosiloxane of formula MM ^Vi DD ^Vi Q consisting of ₂ SiO units, 2.4 wt% of (CH ₃ ) ViSiO units and 9.6 wt% of SiO ₂ units and residues of OH groups;

5970), 상용화 처리 (열 또는 표면 관능화) 를 겪지 않은것.Calcium carbonate, CaCO ₃ (Albacar

5970), not undergoing commercialization treatment (heat or surface functionalization).

2002 ES3 NAT3 (회사: Atofina), 폴리아미드-12 비드, 평균 입자 직경: 30 ㎛.-Orgasol

2002 ES3 NAT3 (Atofina), polyamide-12 beads, average particle diameter: 30 μm.

2) Procedure and Results:

a) the composition was prepared from a 2-pack precursor:

100 parts by weight of the A part and 10 parts by weight of the B part of the 2-pack system were mixed together at room temperature to obtain a control composition (C-1) (see the composition in Table 1).

At room temperature were mixed together to obtain the composition (I-1) according to the invention:

2002 ES3 NAT3 비드의 25 중량부를 혼합하여 수득한 A-1 부분의 125 중량부, 및100 parts by weight of part A of composition C-1 and Orgasol

125 parts by weight of the A-1 moiety obtained by mixing 25 parts by weight of 2002 ES3 NAT3 beads, and

10 parts by weight of composition B-1 having the same composition as the B portion of composition C-1

b) Yarn count of 235 decitex (dtex) by coating each mixture (C-1 and I-1) with a doctor blade or roll (variable coating rate expressed in g / m ² ) Forms a precipitate on a desized 6.6 type polyhexamethyleneadipamide fabric having

c) The resulting layer was cured in the Mathis oven at 180 ° C. for 80 seconds to give an elastomer. The results of the comparative test are shown in Tables II to IV.

The coefficient of friction (Ks) was measured according to standard NFQ 03-082. Table II shows the measurement of the friction coefficient obtained by rubbing on the glass plate. Table III shows the measurement of the coefficient of friction obtained by rubbing a sample of the coated side itself, coated side to side.

TABLE I

Composition C-1 A part Number of parts by weight Composition containing 40% by weight of resin (V) and 60% by weight of diluent (A) 48 Ethinylcyclohexanol 1 0.025 High Viscosity Oils (I) 28 CaCO ₃ 16 Oil (II) 6 VTMO One CLYMO One Part B Composition containing 40% by weight of resin (V) and 60% by weight of diluent (A) 45 High Viscosity Oils (I) 51 TBT 4 catalyst 0.02

When the precipitation as amounts per unit area of the coated fabric are similar, it has been found that the composition I-1 according to the invention leads to a smaller coefficient of friction compared to the coefficient of friction (COF) obtained with the control composition C-1.

The coated fabric samples were then tested according to standard methods in the airbag manufacturing industry. The results are compared to Table IV below.

The test for durability and wear resistance ("rubbing" test) (ISO Standard 5981 A) reflects the adhesion and aging behavior of the composition. The test consists of first shearing the fabric using two jaws that are picked up with two opposite edges of the sample and induced to move alternately with respect to each other, and secondly, wear in contact with the mobile support.

Thus, for equivalent coating precipitation, it was found that Formula I-1 enables preservation of the use properties of the fabric as obtained with Formula C-1, while simultaneously improving the coefficient of friction.

Claims (27)

A method of improving the coefficient of friction of a woven, braided, or nonwoven fibrous support, comprising the following steps: a) preparing a curable silicone coating composition (A) comprising: (1) component (a-1) or (a-2): (A-1) corresponding to at least one polyorganosiloxane that can be cured by the action of at least one organic peroxide based catalyst, and (A-2) corresponding to a polyorganosiloxane blend that can be cured by polyaddition, including: At least one polyorganosiloxane (I) containing at least two C2-C6 alkenyl groups linked to silicon per molecule, and At least one polyorganosiloxane (II) containing at least two hydrogen atoms linked to silicon per molecule, (2) An effective amount of a curing catalyst consisting of: one or more organic peroxides when using (a-1), and one or more metals (or compounds) of the platinum group when using (a-2) ), (3) particles of at least one resin (III) comprising at least one (co) polyamide, (4) optionally, one or more reinforcing fillers, (5) one or more adhesion promoters (IV), (6) an additive system (B), optionally consisting of the following mixtures, to which the constituents are added sequentially or simultaneously: At least one polyorganosiloxane resin (V), optionally mixed with at least one polyorganosiloxane, which is present in an amount of up to 60% by weight relative to the total weight of the mixture, and Calcium carbonate (CaCO ₃ ) present in up to 30% by weight relative to the total weight of the mixture; (7) optionally, at least one curing inhibitor (VI), b) applying the silicone coating composition (A) prepared in step a) at least 10 g / m 2 for one or two sides of the woven, braided or nonwoven fibrous support, and c) curing the precipitate formed in step b) by heating up to a temperature that may be up to 210 ° C., electromagnetic radiation, or infrared radiation to form an elastomer. The method of improving the coefficient of friction of a woven, braided or nonwoven fibrous support according to claim 1, wherein the curable silicone coating composition (A) comprises a mixture formed from: (1) one or more polyorganosiloxanes (I) containing at least two C2-C6 alkenyl groups linked to silicon per molecule, (2) one or more polyorganosiloxanes (II) containing two or more hydrogen atoms linked to silicon per molecule, (3) at least one catalytically effective amount of at least one metal belonging to the platinum group, (4) one or more adhesion promoters (IV), (5) particles of at least one resin (III) comprising at least one (co) polyamide, (6) an additive system (B) in which the constituents are added sequentially or simultaneously, consisting of the following mixtures: At least one polyorganosiloxane resin (V), optionally mixed with at least one polyorganosiloxane, which is present in an amount of up to 60% by weight relative to the total weight of the mixture, and Calcium carbonate (CaCO ₃ ) present in up to 30% by weight relative to the total weight of the mixture; (7) optionally, one or more reinforcing fillers, (8) optionally, at least one curing inhibitor (VI), (9) optionally, at least one coloring additive (VII), and (10) optionally, at least one fire resistance improving additive (VIII). The method of improving friction coefficient of a woven, braided or nonwoven fibrous support according to claim 1 or 2, wherein the particles of the resin (III) are in a spherical form. The method of improving the coefficient of friction of a woven, braided or nonwoven fibrous support according to claim 3, wherein the average diameter of the particles of the resin (III) is 5 to 100 m. The coefficient of friction improvement of the woven, braided or nonwoven fibrous support according to claim 1, wherein the particles of resin (III) comprise at least one (co) polyamide selected from the group consisting of: Methods: polyamide-6, polyamide-6.6, polyamide-4, polyamide-11, polyamide-12, polyamide 4-6, 6-10, 6-12, 6-36 and 12-12, and Copolymers and blends thereof. The method of improving the coefficient of friction of a woven, braided or nonwoven fibrous support according to claim 5, wherein the particles of resin (III) comprise polyamide-12. 7. The particle of claim 1, wherein the particles of resin (III) are 40% by weight or less, preferably 1-30% by weight, more preferably 5-20% by weight, based on the total weight of the mixture. A method of improving the coefficient of friction of a woven, braided or nonwoven fibrous support, which is present at a ratio of. The method of improving the coefficient of friction of a woven, braided or nonwoven fiber support according to any one of claims 1 to 7, wherein the adhesion promoter (IV) of the curable silicone coating composition (A) contains only: (IV.1) at least one alkoxy organosilane containing at least one C2-C6 alkenyl group per molecule, (IV.2) at least one organosilicon compound containing at least one epoxy radical, and (IV.3) at least one metal chelate M and / or a metal alkoxide of formula M (OJ) n, wherein n = valence of M, J = linear or branched C 1 -C 8 alkyl, M is Ti, Zr, Selected from the group formed by Ge, Li, Mn, Fe, Al and Mg). The method of improving the coefficient of friction of a woven, braided or nonwoven fibrous support according to claim 8, wherein the alkoxy organosiloxane (IV.1) of the promoter (IV) corresponds to

[In the formula: R ¹ , R ² and R ³ are the same or different hydrogenated or hydrocarbon-based radicals and represent phenyl, linear or branched C 1 -C 4 alkyl optionally substituted with one or more C 1 -C 3 alkyl, or hydrogen, U is a linear or branched C1-C4 alkylene, -W is a valence bond, R ⁴ and R ⁵ are the same or different radicals and represent linear or branched C 1 -C 4 alkyl, x ¹ = 0 or 1, x = 0 to 2; Method for improving the coefficient of friction of the woven, braided or nonwoven fibrous support, wherein the organosilicon compound (IV.2) of the promoter (IV) is selected from: a) product (IV.2a) corresponding to the formula:

[In the formula: R ⁶ is a linear or branched C 1 -C 4 alkyl radical, R ⁷ is a linear or branched alkyl radical, y is 0, 1, 2 or 3, X is defined by the formula:

(here: E and D are the same or different radicals, selected from linear or branched C1-C4 alkyl, z is 0 or 1, R ⁸ , R ⁹ and R ¹⁰ are the same or different radicals, representing linear or branched C 1 -C 4 alkyl or hydrogen, R ⁸ and R ⁹ or R ¹⁰ can alternatively form a 5- to 7-membered alkyl ring with two carbons having an epoxy), or b) product (IV.2b) consisting of an epoxy-functional polydiorganosiloxane containing: (i) at least one siloxane unit of formula:

[In the formula: X is a radical as previously defined for formula (IV.2a), G is a monovalent hydrocarbon-based group having no adverse action on the activity of the catalyst and is selected from alkyl groups of 1 to 8 carbon atoms, including aryl groups, optionally substituted with one or more halogen atoms, p = 1 or 2, q = 0, 1 or 2, -p + q = 1, 2 or 3], (2i) optionally, at least one siloxane unit of formula:

Wherein Formula G has the same meaning as described above and r is equal to 0, 1, 2 or 3. 9. A method of improving the coefficient of friction of woven, braided or nonwoven fibrous supports according to claim 8, wherein the metal M and / or alkoxide (IV.3) of the chelate is selected from the following list: Ti, Zr, Ge, Li or Mn. 12. The method of improving the coefficient of friction of a woven, braided or nonwoven fibrous support according to claim 9, 10 or 11, wherein the adhesion promoter (IV) contains a mixture of: Vinyltrimethoxysilane (VTMO), which is a representative example of formula (IV.1), 3-glycidoxypropyltrimethoxysilane (GLYMO), which is a representative example of formula (IV.2), and Butyl titanate, which is a representative example of formula (IV.3). The method of improving the coefficient of friction of a woven, braided or nonwoven fibrous support according to any one of claims 1 to 12, wherein the polyorganosiloxane (I) comprises: (i) siloxane units of the formula:

[In the meal, The symbol R ¹ represents an alkenyl group, preferably vinyl or allyl, The symbol Z, which may be the same or different, is each selected from an alkyl group of 1 to 8 carbon atoms and also an aryl group, which is a monovalent hydrocarbon-based group with no adverse action on the activity of the catalyst, optionally substituted with one or more halogen atoms, a is 1 or 2, b is 0, 1 or 2 and the sum of a + b is equal to 1, 2 or 3, and optionally (ii) other siloxane units of the formula:

[In the meal, Z has the same meaning as above and c is 1, 2 or 3; The method of improving the coefficient of friction of a woven, braided or nonwoven fibrous support according to any one of claims 1 to 13, wherein the polyorganosiloxane (II) comprises: Siloxane units of the formula:

[In the meal, L groups, which may be the same or different, each represent a monovalent hydrocarbon-based group with no adverse action on the activity of the catalyst, preferably an alkyl group containing from 1 to 8 carbon atoms, optionally substituted with one or more halogen atoms and Advantageously selected from methyl, ethyl, propyl and 3,3,3-trifluoropropyl groups, and aryl groups, and advantageously from xylyl, tolyl or phenyl radicals, d is 1 or 2, e is 0, 1 or 2 and the sum of d + e is equal to 1, 2 or 3, and Optionally, at least some of the other units are units of the following average formula:

(Wherein L group has the same meaning as above and g is equal to 0, 1, 2 or 3). 15. The process according to any one of claims 1 to 14, wherein the ratio of polyorganosiloxanes (I) and (II) is selected from hydrogen atoms linked to silicon in (II) to alkenyl radicals linked to silicon in (I). A method of improving the coefficient of friction of a woven, braided or nonwoven fibrous support, wherein the molar ratio is from 0.4 to 10, preferably from 0.6 to 5. Curable silicone coating composition (A) containing: (1) component (a-1) or (a-2): (A-1) corresponding to at least one polyorganosiloxane that can be cured by the action of a catalyst based on at least one organic peroxide, and (A-2) corresponding to a polyorganosiloxane blend which can be cured by a polyaddition reaction containing: At least one polyorganosiloxane (I) containing at least two C2-C6 alkenyl groups linked to silicon per molecule, and At least one polyorganosiloxane (II) containing at least two hydrogen atoms linked to silicon per molecule, (2) an effective amount of a curing catalyst containing: at least one organic peroxide in the case of use of (a-1), and at least one metal (or compound) of the platinum group in the case of use of (a-2), (3) particles of at least one resin (III) containing at least one (co) polyamide, (4) optionally, one or more reinforced fillers, (5) optionally, at least one curing inhibitor (VII), (6) optionally, at least one coloring additive (VII), and (7) optionally at least one additive (VIII) for improving fire resistance, (8) one or more adhesion promoters (IV), (9) Additive system (B) for improving coaming strength and tearing strength, optionally consisting of the following mixtures, the components of which are added sequentially or simultaneously: One or more polyorganosiloxane resins (V), optionally up to 60% by weight relative to the total weight of the mixture, optionally mixed with one or more polyorganosiloxanes that act as diluents, and Calcium carbonate (CaCO ₃ ) present in up to 30% by weight relative to the total weight of the mixture. The curable silicone coating composition (A) according to claim 16, comprising: (1) one or more polyorganosiloxanes (I) containing at least two C2-C6 alkenyl groups linked to silicon per molecule, (2) one or more polyorganosiloxanes (II) containing two or more hydrogen atoms linked to silicon per molecule, (3) a catalytically effective amount of at least one catalyst (III), consisting of at least one metal belonging to the platinum group, (4) particles of at least one resin (III) containing at least one (co) polyamide, (5) one or more adhesion promoters (IV), (6) an additive system consisting of the following mixtures, the constituents of which are added sequentially or simultaneously to the mixture: One or more polyorganosiloxane resins (V), optionally up to 60% by weight relative to the total weight of the mixture, optionally mixed with one or more polyorganosiloxanes that act as diluents, and Calcium carbonate (CaCO ₃ ) present in up to 30% by weight relative to the total weight of the mixture. (7) optionally, at least one curing inhibitor (VI), (8) optionally, one or more reinforced fillers, (9) optionally, one or more coloring additives (VII), and (10) optionally at least one additive (VIII) for improving fire resistance. The curable silicone coating composition (A) according to claim 16 or 17, wherein the particles of the resin (III) are spherical in shape. The curable silicone coating composition (A) according to claim 18, wherein the average diameter of the particles of the resin (III) is 5 to 100 µm. 20. The particle of any of claims 16-19 wherein the particles of resin (III) are polyamide-6, polyamide-6.6, polyamide-4, polyamide-11, polyamide-12, polyamide 4-. 6, 6-10, 6-12, 6-36 and 12-12 and a (co) polyamide substrate selected from the group consisting of copolymers and blends thereof. The curable silicone coating composition (A) according to claim 20, wherein the particles of resin (III) comprise polyamide-12. 22. The composition of any of claims 16 to 21, wherein the adhesion promoter (IV) comprises a mixture of: Vinyltrimethoxysilane (VTMO), a representative example of formula (IV.1), 3-glycidoxypropyltrimethoxysilane (GLYMO), which is a representative example of formula (IV.2), and Butyl titanate, which is a representative example of formula (IV.3). 23. The particle of any of claims 16 to 22 wherein the particles of resin (III) are up to 40% by weight, preferably 1 to 30% by weight, and more preferably 5 to 20, based on the total weight of the mixture. Composition present in a percentage by weight. 2-pack or multi-pack precursor system (C) for the curable silicone coating composition (A) according to any one of claims 16 to 23, comprising: Two separate A and B parts intended to be mixed together to form the composition, and One of these A or B moieties containing a catalyst and only one polyorganosiloxane species (I) or (II). Woven, braided or nonwoven fibrous supports, coated with one or two sides with an elastomer, which can be obtained by the following; a)-weaving the resulting composition by mixing the silicone coating composition (A) according to any one of claims 16 to 23 or the A and B portions of the two-pack system (B) according to claim 24, Applying at least 10 g / m ² on one or both sides of the braided or nonwoven fiber support, and   Curing the precipitation formed in the preceding step to form an elastomer, either by electromagnetic radiation or by infrared radiation or by heating to a temperature which may be up to 210 ° C., or b) The method according to any one of claims 1 to 15. The curable silicone composition (A) according to any of claims 16 to 23, the two-pack or multi-pack system (C) according to claim 24. Or in the field of inflatable bags for automotive use of a woven, braided or nonwoven fibrous support coated on one or both sides according to claim 25. An inflation bag comprising a woven, braided or nonwoven fibrous support coated on one or two sides according to claim 25.