FR2800382A1 - SILICONE COMPLEX / ADHESIVE ANTI-ADHERENT WITH STABILIZATION ADDITIVE - Google Patents

Abstract

The subject of the present invention is a silicone/release adhesive complex comprising at least one silicone coating applied to a first support and an adhesive coating applied to a second support, characterized in that the said adhesive coating comprises, as an additive intended to stabilize over time the peeling force of a silicone/adhesive interface at least one salt of an element of group IA or IIA of the periodic table with a compound chosen from: - carboxylates of formula OCOR(-), with R representing a linear, branched or cyclic, saturated, unsaturated or aromatic C1 to C12 alkyl radical and, where appropriate, substituted by one or more halogen atoms - fluorophosphates such as potassium hexafluorophosphate, - fluorosulfonates such as potassium trifluoromethanesulfonate potassium, and - esters or salts of phosphoric acid such as K3 PO4 , K4 P2 O7 , (CF DRAWING IN BOPI) with n=1 or 2, HK2 PO4 , KH2 PO4 .

Description

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 The present invention generally relates to so-called self-adhesive complexes in which a crosslinked or polymerized silicone matrix is associated with an adhesive. This silicone matrix may in particular be applied to the surface of a support so as to render it non-stick with respect to the adhesive. This type of adhesive / silicone complex is more particularly used for producing adhesive protective papers such as labels, decorative papers and adhesive tapes.

 These complexes can be prepared according to an in-line method which involves the successive steps including in particular the deposition of a crosslinkable and / or polymerizable organopolysiloxane composition on a support-type material, its crosslinking and / or polymerization by means of energy input. to form a silicone coating, the application on this coating of an adhesive generally in the form of a wet emulsion, the drying of this emulsion and the application of a second support.

The adhesive / silicone complex thus formed is then generally stored for a longer or shorter duration on coils.

 The silicone coating of these complexes therefore has the primary function of providing the interface between the support and the adhesive. However, it must also establish with the adhesive a sufficiently weak connection so that they can be easily separated from one another.

 Consequently, an essential property of these complexes must be to confer a detachment force with respect to the sufficiently weak adhesive, and which can be stabilized during prolonged storage of the complexes on the coils at the end of their manufacture. Indeed, insofar as these coils can sometimes reach more than one meter in diameter, a very high pressure is then exerted on the adhesives. Under the effect of this pressure, the adhesive can interact with the silicone and cause peeling difficulties, incompatible with the end use of these complexes.

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 especially as easily peelable adhesive labels or adhesive tapes.

 In this case, this binding force, also known as the peel force, can be quantified. Although it can vary significantly according to the measurement method adopted, it can be broadly characterized, for a low separation speed of the order of 30 cm / min, as follows: - a release force of less than 23, 62 g / cm is considered low, - a peel force greater than 23.62 g / cm and less than 59.05 g / cm is considered medium, and - a peel force greater than 59.05 g / cm and preferably less than 157.48 g / cm is considered high.

 The present invention aims in particular to provide a silicone / adhesive complex whose peel force can be stabilized at a value of less than 59.05 g / cm for a peel rate of the order of 30 cm / min.

 More particularly, the object of the invention is to provide non-stick silicone systems whose release forces also remain stable during aging of the complexes and therefore during storage particularly in the circumstances mentioned above.

 This object is precisely achieved according to the present invention by the introduction into the adhesive component of a silicone / adhesive complex of at least one stabilizer so as to act on an interface between the adhesive and the silicone.

 More particularly, the present invention relates to a silicone / non-stick adhesive complex comprising at least one silicone coating applied to a first support and an adhesive coating applied to a

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(CH3)(CH2)7CH=CH(CH2),COOK, (CH3COO)2Ca, CH3-COOK,
CF3COOK, (CH30)2P(0)CH2COOK), - les fluorophosphates tels l'hexafluorophosphate de potassium, - les fluorosulfonates tel le trifluorométhanesulfonate de potassium, et - les esters ou sels de l'acide phosphorique comme K3P04, K4P2O7,

(Me3SiO)nOK avec n=1 ou 2, HK2PO4, KH2po4'
O
Les additifs mis en oeuvre selon l'invention possèdent de préférence au moins un élément du groupe IA ou IIA de la classification périodique. second support, characterized in that said adhesive coating comprises as additive for stabilizing over time the release force of a silicone / adhesive interface at least one salt of a group IA or IIA element of the classification periodic system with a compound chosen from: - carboxylates of formula OCORe, with R representing a linear, branched or cyclic alkyl radical, saturated, unsaturated or aromatic C1 to C12 and optionally substituted for example by one or more halogen atoms . (as examples of carboxylates, mention may be made of (C 2 H 5) (C 4 H 9) CHCOOK,

(CH3) (CH2) 7CH = CH (CH2), COOK, (CH3COO) 2Ca, CH3-COOK,
CF 3 COOK, (CH 3 O) 2 P (O) CH 2 COOK), fluorophosphates such as potassium hexafluorophosphate, fluorosulphonates such as potassium trifluoromethanesulphonate, and esters or salts of phosphoric acid such as K 3 PO 4, K 4 P 2 O 7,

(Me3SiO) nOK with n = 1 or 2, HK2PO4, KH2po4 '
O
The additives used according to the invention preferably have at least one element from group IA or IIA of the periodic table.

 Group IA or IIA elements are preferably selected from potassium or calcium.

 For the purposes of the present invention, the action of the additive results in a prolonged stabilization over time, of the release force at a silicone coating and adhesive coating interface, at a sufficient amplitude to be compatible with a subsequent detachment of the two coatings such as for example in the end use of these complexes as easily peelable adhesive labels or adhesive tapes.

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 According to a first variant, the two supports consist of two different materials, arranged so that the silicone coating of the first support is in contact with the adhesive coating of the second support. This embodiment is in particular illustrated by systems called self-adhesive labels. In this particular case, the detachment force of the silicone / adhesive interface is exerted during the separation of the two supports.

 In a second variant, the two supports are respectively constituted by each of the two faces of the same material. This second embodiment is in particular illustrated by the systems known as adhesive tapes. The non-stick coating, that is to say based on the silicone coating and the adhesive coating will be brought into contact during the winding of the support on itself. In this case, the detachment force is exerted at the silicone / adhesive interface under the effect of the separation of a lower face, an upper face of the material.

 For the purposes of the invention, a peel force is considered to be stabilized if, relative to its original amplitude, it does not change by more than a factor of 8, preferably 5 and more preferably of 3, to 1. resulting from an aging test called FINAT 10, representative of aging for 3 to 6 months at 20 ° C. under pressure conditions of 70 g / cm 2.

 Preferably, the initial peel force, evaluated according to the FINAT 3 test, representative of aging for 20 hours at 20 ° C. under pressure conditions of 70 g / cm 2 and exerted at the level of the silicone / adhesive interface, is lower at 31.49 g / cm and more preferably at 23.62 g / cm.

 By way of illustration of the additives which are suitable for the invention for stabilizing the release force, there may be mentioned potassium and calcium carbonate and bicarbonate, potassium hydrogenophthalate,

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 potassium dimethylphosphonoacetate, potassium hydrogen tartrate, potassium hydrogen phosphates, potassium acetate, potassium oxalate and potassium trifluoromethanesulfonate.

 Of course, the choice of this additive is made taking into account its degree of solubility in the adhesive component retained.

 The additive can be introduced into the adhesive up to 5% by weight. Its quantity may thus vary between 0.001% and 5% and preferably between 0.01% and 1% by weight.

 In the context of the present invention, it is possible to choose an adhesive of the following types: acrylic in the aqueous phase, or in the solvent phase, hot melt or photocrosslinkable, gums of the natural or synthetic rubber type in the aqueous phase or in the solvent phase, hot melt or photocrosslinkable latexes or other suitable adhesives.

 In general, the adhesives coated on the surface of a wide variety of materials so as to obtain labels, ribbons or any other self-adhesive material are emulsions known as pressure-sensitive adhesive emulsions (PSA) which derive mainly from acrylic polymers. These emulsions have the advantage of giving the material the ability to adhere to the surface of a support, without requiring activation other than a low pressure. PSAs are conventionally obtained by polymerization, for the most part, of alkyl acrylate monomers which are generally present in a proportion of 50 to approximately 99% and preferably in a proportion of 80 to 99% by weight, if appropriate mixed with polar copolymerizable monomers such as for example acrylic acid, in smaller proportions.

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 In fact, these PSA have residual acidity or formulation additives capable of interacting with functional groups present on the silicone coating to which the said PSA is or must be juxtaposed and thus to disrupt the adhesive / silicone release forces. It seems that one of the actions of the additive is precisely to neutralize, at least in part, this type of undesirable interactions.

 The element of group IA or IIA of the additive according to the invention is especially capable of acting with the ends of carboxylic or carboxylate chains of the adhesive and more particularly PSA.

 As previously indicated, these emulsions, known as pressure sensitive adhesive emulsions (PSA), are obtained by predominantly polymerization of alkyl acrylate monomers.

 The monomers used to prepare the PSAs are selected according to their glass transition temperature, Tg, to give the polymers incorporating them the expected behavior in terms of adhesion and viscoelasticity. For this purpose, the monomers preferably have a sufficiently low glass transition temperature, generally between -70 and -10 C and preferably below -30 C.

 More specifically, these monomers are chosen from the group consisting of (meth) acrylic esters such as esters of acrylic acid and of methacrylic acid with hydrogenated or fluorinated C1-C12 alkanols, preferably C1-C8, especially methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, tert-butyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, isooctyl acrylate,

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 decyl, dodecyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate; vinyl nitriles, especially those having 3 to 12 carbon atoms, such as in particular acrylonitrile and methacrylonitrile; vinyl esters of carboxylic acid such as vinyl acetate, vinyl versatate, vinyl propionate, ethylenically unsaturated mono- and dicarboxylic acids such as acrylic acid, methacrylic acid, acid itaconic acid, maleic acid, fumaric acid and mono- and di-alkyl esters of mono- and di-carboxylic acids of the type mentioned with alkanols preferably having 1 to 8 carbon atoms and their N-substituted derivatives, amides of unsaturated carboxylic acids such as acrylamide, methacrylamide, N-methylolacrylamide or methacrylamide, N-alkylacrylamides, ethylenic monomers containing a sulfonic acid group and its alkali or ammonium salts, for example vinylsulfonic acid, the acid vinylbenzenesulfonic acid, alpha-acrylamido methylpropanesulfonic acid, 2-sulfoethylene methacrylate, unsaturated ethylenic monomers having a secondary, tertiary or quaternary amino group, or a nitrogen-containing heterocyclic group such as, for example, vinylpyridines, vinylimidazole, aminoalkyl (meth) acrylates and aminoalkyl (meth) acrylamides such as dimethylaminoethyl acrylate or dimethylaminoethyl methacrylate, ditertiobutylaminoethyl acrylate or ditertiobutylaminoethyl methacrylate, dimethylaminomethyl-acrylamide or dimethylaminomethylmethacrylamide, zwitterionic monomers such as, for example, sulfopropyl (dimethyl) aminopropyl acrylate,

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 ethylenic monomers carrying a sulfate group, ethylenic monomers bearing phosphate or phosphonate functions, and mixtures thereof.

 Preferably, the monomers employed in the emulsion polymerization are predominantly alkyl (meth) acrylate monomers, present in a proportion of from 50% to approximately 99% and preferably from 80% to 99% by weight. relative to the weight of monomers present in the emulsion.

 These alkyl acrylate monomers preferably have from 4 to about 8 carbon atoms in the alkyl chain.

 More preferably, they are chosen at least from 2-ethylhexyl acrylate, butyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, iso acrylate and the like. -octyl, decyl acrylate, isobutyl acrylate, dodecyl acrylate, methacrylates such as n-butyl methacrylate, methacrylic acid, acrylic acid, itaconic acid, acid maleic and / or acrylamide.

 Also suitable are hot-melt adhesive compositions (photocrosslinkable or not), such as those described in US Pat. No. 5,536,772 and WO 97/00300.

 The PSA suitable for the invention can in particular be obtained by radical emulsion polymerization at atmospheric pressure and at a temperature generally of between 10 and 90 ° C., corresponding monomers. Classically, this polymerization technique requires, in addition to the radical initiator, a mixture of anionic and / or nonionic emulsifiers for stabilizing said emulsion.

Similarly, the polymerization can be carried out in the presence of at least one monomer called said crosslinking agent. The emulsion polymerization of

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 monomers may be carried out in the presence of at least one radical initiator and, if appropriate, a transfer agent, with a monomer concentration of between about 20 and 75% by weight of the emulsion. The monomers can be introduced in the form of a preemulsion in the reaction medium. Any type of free radical initiator or initiator customary in emulsion polymerization may be suitable.

Examples of initiators include hydroperoxides such as hydrogen peroxide, isopropyl benzene hydroperoxide, sodium, potassium or ammonium persulfates, and cationic initiators such as azobis (isobutyronitrile) 4-4. azobis (4-cyano valeric acid). The amount of initiator (s) is generally between 0.05 and 2% by weight relative to the amount of the monomers.

 The additive according to the invention may be introduced at the end of this polymerization, that is to say in the final emulsion or in the hot melt, before or immediately before its use, as an adhesive component for the preparation of a silicone / adhesive complex.

 As regards the silicones that may be associated with the adhesive, they derive from the crosslinking and / or polymerization of monomer (s), oligomer (s) or polymer (s) of organopolysiloxane nature. The nature of these monomer (s), oligomer (s) or polymer (s) can vary widely. Their mode of activation, namely thermal, photochemical or electron beams, is selected according to the family of siloxanes used.

 As regards more particularly the monomer (s), oligomer (s) and polymer (s) of organopolysiloxane nature crosslinkable cationically, thermal activation, UV and / or electron beam, they generally consist of units of formula ( 1) and terminated by units of formula (II) or cyclic consisting of units of formula (I) represented below:

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dans lesquelles : - les symboles R1 et R2 sont semblables ou différents et représentent : un radical alkyle linéaire ou ramifié contenant 1 à 8 atomes de carbone, éventuellement substitué par au moins un halogène, de préférence le fluor, les radicaux alkyle étant de préférence méthyle, éthyle, propyle, octyle et 3,3,3-trifluoropropyle, un radical cycloalkyle contenant entre 5 et 8 atomes de carbone cycliques, éventuellement substitué, un radical aryle contenant entre 6 et 12 atomes de carbone pouvant être substitué, de préférence phényle ou d ichlorophényle, une partie aralkyle ayant une partie alkyle contenant entre 5 et
14 atomes de carbone et une partie aryle contenant entre 6 et
12 atomes de carbone, substituée éventuellement sur la partie aryle par des halogènes, des alkyles et/ou des alkoxyles contenant 1 à 3 atomes de carbone, - les symboles Z sont semblables ou différents et représentent : un groupement R1 et/ou R2, un radical hydrogène, et/ou un groupement organofonctionnel réticulable, de préférence époxy et/ou alcényléther et/ou oxétane et/ou

in which: the symbols R 1 and R 2 are identical or different and represent: a linear or branched alkyl radical containing 1 to 8 carbon atoms, optionally substituted by at least one halogen, preferably fluorine, the alkyl radicals being preferably methyl , ethyl, propyl, octyl and 3,3,3-trifluoropropyl, a cycloalkyl radical containing between 5 and 8 ring carbon atoms, optionally substituted, an aryl radical containing between 6 and 12 carbon atoms which may be substituted, preferably phenyl or dichlorophenyl, an aralkyl moiety having an alkyl moiety containing between 5 and
14 carbon atoms and an aryl part containing between 6 and
12 carbon atoms, optionally substituted on the aryl part by halogens, alkyls and / or alkoxyls containing 1 to 3 carbon atoms, - the symbols Z are similar or different and represent: a group R1 and / or R2, a hydrogen radical, and / or a crosslinkable organofunctional group, preferably epoxy and / or alkenyl ether and / or oxetane and / or

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 dioxolane, connected to the silicon of the polyorganosiloxane via a divalent radical containing from 2 to 20 carbon atoms and which may contain at least one heteroatom, preferably oxygen, with at least one of the Z symbols representing a crosslinkable functional organic group.

 According to an advantageous variant of the invention, the polyorganosiloxanes used comprise from 1 to 10 organofunctional groups per macromolecular chain. For an epoxyfunctional group this corresponds to epoxide levels ranging from 20 to 2000 meq. molar / 100 g of polyorganosiloxane.

 The linear polyorganosiloxanes may be oils with a dynamic viscosity at 25 ° C., of the order of 10 to 10,000 mPa.s at 25 ° C., generally of the order of 50 to 5,000 mPa.s at 25 ° C., and more preferably still, from 100 to 600 mPa.s at 25 ° C., or gums having a molecular weight of the order of 1,000,000.

 When it comes to cyclic polyorganosiloxanes, these consist of units (1) which may be, for example, of the dialkylsiloxy or alkylarylsiloxy type. These cyclic polyorganosiloxanes have a viscosity of the order of 1 to 5000 mPa.s.

As examples of divalent radicals linking an organofunctional group of the epoxy type, mention may be made of those included in the following formulas:

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With regard to the organofunctional groups of the alkenyl ether type, those contained in the following formulas may be mentioned: - (O) n '- (CH 2) n "-O-CH = CH 2; - (O) n' - (CH 2) n -R 3 -O-CH = CH 2; In which: # n 'represents 0 or 1 and n "an integer between 1 and 5 # R3 represents: branched or cyclic C1-C12, optionally substituted, - or a C5-C12 arylene radical, preferably phenylene, optionally substituted, preferably with one to three C1-C6 alkyl groups, # R4 represents a linear or branched alkyl radical in C1-C6.

 The epoxy or alkenyl ether functional polyorganosiloxanes are generally in the form of fluids having a viscosity at 25 ° C. of 10 to 10,000 mm 2 / s and preferably of 100 to 600 mm 2 / s.

 The dynamic viscosity at 25 ° C. of all the silicones considered in the present description can be measured using a BROOKFIELD viscometer, according to the AFNOR NFT 76 102 standard of February 1972.

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 This type of compounds is described in particular in DE-A 4,009,889; EP-A-396,130; EP-A-355,381; EP-A-105,341; FR-An 2,110,115; FR-A-2,526,800.

 The alkenyletherfunctional polyorganosiloxanes can be prepared by hydrosilylation reaction between Si-H-type oils and vinyloxyfunctional compounds such as allylvinylether, allyl-vinyloxyethoxybenzene ...

 The epoxy functional polyorganosiloxanes can be prepared by hydrosilylation reaction between oils with Si-H units and epoxyfunctional compounds such as 4-vinylcyclohexeneoxide, allylglycidylether, and the like.

 The silicones that best meet the object of the invention are described below and have at least one epoxide group, alkenyl ether or oxetane.

In the following formulas X may represent an alkyl group; cyclohexyl; trifluoropropyl; perfluoroalkyl; alkoxy or hydroxypropyl, R a hydrogen atom; or an alkyl or cycloalkyl group; alkenyl or alkenyl and (0 # a # 1000); (1 <b <1000)

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Other crosslinkable and / or polymerizable silicones by thermal activation are more particularly derived from polyorganosiloxanes A having, by molecule, at least one Si-H reactive radical and no silicon atom bound to more than two hydrogen atoms and selected B compounds. preferably from among the polyorganosiloxanes and having, per molecule, at least one unsaturated aliphatic reactive group and / or at least one reactive functional group.

Advantageously, the compounds A are chosen from polyorganohydrogensiloxanes comprising: * units of the following formula:
HaWbSiO4- (a + b) (1)
In which: the symbols W are identical or different and represent a monovalent hydrocarbon group, preferably chosen from (cyclo) alkyl groups having from 1 to 18 carbon atoms inclusive and, advantageously, from methyl or ethyl groups; propyl, octyl and 3,3,3-trifluoropropyl, as well as from C 6 -C 12 aryl or aralkyl groups and, advantageously, from xylyl and tolyl and phenyl radicals,

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 all these groups being optionally halogenated (fluorine for example) and / or hydroxylated and / or alkoxylated.

- a is 1 or 2, b is 0,1 or 2, with the sum (a + b) having a value between 1 and 3, * and possibly other units of average formula:
WcSiO4-c (2)
2 in which W has the same meaning as above and ca a value between 0 and 3.

 The organopolysiloxane A may be formed solely of a unit of formula (1) or may further comprise units of formula (2).

 It may have a linear structure, branched or unbranched, cyclic or networked. The degree of polymerization is greater than or equal to 2. More generally, it is less than 5000.

H(CH3)Si0"2, H(CH3)SiOv2, H(C6H5)SiOz2. Examples of units of formula (1) are:

H (CH 3) SiO 2, H (CH 3) SiO 2, H (C 6 H 5) SiO 2.

 When it comes to linear polymers, these essentially consist of D W2SiO2 / 2, WHSiO, and M W3SiO1 / 2, WH2SiO1 / 2 units; the M terminal blocking units may be trialkylsiloxy, dialkylarylsiloxy groups.

 As examples of terminal M units, mention may be made of trimethylsiloxy, dimethylphenylsiloxy, dimethylethoxysiloxy and dimethylethyltriethoxy-silylsiloxy groups.

 By way of example of D units, mention may be made of dimethylsiloxy and methylphenylsiloxy groups.

 These linear polyorganosiloxanes may be oils with a dynamic viscosity at 25 ° C. of the order of 1 to 100,000 mPa.s at 25 ° C.

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 generally of the order of 10 to 5000 mPa.s at 25 C, or gums having a molecular weight of the order of 1,000,000.

 In the case of cyclic polyorganosiloxanes, these consist of D W 2 SiO 2 / and WHSiO units, which may be of the dialkylsiloxy or alkylarylsiloxy type. They have a viscosity of the order of 1 to 5000 mPa.s.

 The dynamic viscosity at 25 ° C. all the polymers considered in the present disclosure can be measured using a BROOKFIELD viscometer, according to the AFNOR NFT 76 102 standard of February 1972.

 Examples of organopolysiloxanes A are: - dimethylpolysiloxanes with hydrogenodimethylsilyl ends, - dimethylhydrogenomethylpolysiloxane copolymers with trimethylsilyl ends, - dimethylhydrogenomethylpolysiloxane copolymers with hydrogenodimethylsilyl ends, - trimethylsilyl-terminated hydrogenomethylpolysiloxanes, - cyclic hydrogenomethylpolysiloxanes.

With regard to organopolysiloxanes B, namely having, per molecule, at least one unsaturated aliphatic reactive group and / or at least one reactive functional group, they are preferably selected from polyorganosiloxanes comprising similar or different units of formula:
W'dXeYfSiO4- (d + e + f) (3)
2 in which: the symbols W 'correspond to the same definition as that given above for W,

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 the symbols X are identical or different and represent a hydrogen atom or a reactive function, preferably epoxyfunctional, connected to silicon by a divalent radical, for example C 1 -C 20, optionally comprising at least one heteroatom, radicals X plus particularly preferred being: 3-glycidoxypropyl, 4-ethanediyl (1,2-epoxycylohexyl) ..., the symbols Y are similar or different and represent a linear or branched C 1 -C 12 alkenyl residue, and having at least one ethylenic unsaturation at the chain end and / or in the chain and optionally at least one heteroatom; d, e and f are 0, 1, 2 or 3; - d + e + f = 0, 1, 2 or 3; the level of SiO4 / 2 units being less than 30 mol%.

 With regard to the radicals Y, they are advantageously chosen from the following list: vinyl, propenyl, 3-butenyl, 5-hexenyl, 9 decenyl, 10undecenyl, 5,9-decadienyl, 6-11-dodecadienyl.

 These organopolysiloxanes may have a linear structure (branched or unbranched) cyclic or in a network. Their degree of polymerization is preferably between 2 and 5000.

 When it comes to linear polymers, these essentially consist of D W2SiO2 / 2, XsiO units. Y SiO. and M W3SiO1 / 2, WYSiO1 / 2, W2XsiO1 / 2, the M terminal blocking units may be trialkylsiloxy, dialkylarylsiloxy, dialkylvinylsiloxy, dialkylalkenylsiloxy groups.

 As examples of terminal M units, mention may be made of trimethylsiloxy, dimethylphenylsiloxy, dimethylvinylsiloxy, dimethylhexenylsiloxy, dimethylethoxysiloxy and dimethylethyltriethoxysiloxy groups.

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 As examples of D units, mention may be made of dimethylsiloxy, methylphenylsiloxy, methylvinylsiloxy, methylbutenylsiloxy, methylhexenylsiloxy, methyldecenylsiloxy, methyldecadienylsiloxy, methyl-3hydropropylsiloxy, methyl-3-glycidoxypropyl-siloxy, methyl-2 (3 ', 4'- epoxycyclohexyl) ethylsiloxy, methylbutoxysiloxy, methyl-p-trimethoxysilylethylsiloxy, methyl-p-triethoxysilylethylsiloxy.

 Said linear polyorganosiloxanes may be oils with a dynamic viscosity at 25.degree. C. of the order of 1 to 100 000 mPa.s at 25.degree. C., generally of the order of 10 to 5000 mPa.s at 25.degree. molecular weight of the order of 1,000,000.

 In the case of cyclic polyorganosiloxanes, these are cosntitued with D W2SiO2 / 2, WSiO units. WYSiO. which may be of the dialkylsiloxy, alkylarylsiloxy, alkylvinylsiloxy, alkylsiloxy, alkylXsiloxy type; examples of such patterns have already been cited above.

 Said cyclic polyorganosiloxanes B have a viscosity of the order of 1 to 5000 mPa.s.

 The aliphatically unsaturated compounds B used in the process according to the invention are, for example, those with olefinic or acetylenic unsaturation well known in the relevant technical field. In this regard, reference can be made to U.S. Patents 3,159,662,3,220,272 and 3,410,886 which describe the above compounds.

 According to an advantageous variant of the invention, the reaction mixture comprises compounds A and compounds B in an amount such that the molar ratio of Si-H / unsaturated groups and / or reactive functional group, that is to say epoxy, is between 0.4 and 10, preferably between 1 and 4 and, more preferably, on the order of 1.7.

 The hydrosilylation reaction conditions by thermoactivation are the usual conditions. They are generally catalysed by

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 platinum thermosensitive complexes. As an illustration of these catalysts, mention may in particular be made of the KARSTEDT catalyst. The catalyst is present in a proportion of from 1 to 400, preferably from 10 to 300, and more preferably from 20 to 200 ppm of platinum metal expressed by weight relative to the polyorganosiloxane compound used.

 In addition to this catalyst, the silicone coating components contain an inhibitor of the reaction. In fact, heat is used to deactivate this inhibitor and to allow the start of crosslinking.

Examples of suitable inhibitors include dialkyl carboxylic esters such as dialyl maleate or fumarate, α-acetylenic alcohols or hydroperoxides.

 The complexes according to the invention may furthermore comprise other ingredients such as pigments, photosensitizers for fungicidal, bactericidal and antimicrobial agents, corrosion inhibitors, etc.

 The amounts of coating deposited on the supports are variable.

 The amounts of silicone coating generally range from 0.1 to 5 g / m 2 of treated surface. These amounts depend on the nature of the supports and the desired anti-adherent properties. They are more often between 0.5 and 1.5 g / m2 for non-porous supports.

 As regards the amounts of adhesive coating, they are preferably less than 200 g / m 2 and more preferably less than 100 g / m 2.

 The support may be chosen from a metallic material such as a cellulosic white iron of the paper or cardboard type, for example, or of a vinyl-type polymeric material. Thermoplastic polymeric films

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 as polyethylene, polypropylene or polyester are particularly advantageous.

 In the embodiment where the adhesive coating is in contact with a support constituted by a second material, this second material may be chosen from the materials proposed for the first support and may be identical in nature or not to the first support.

 Finally, the support on which the silicone coating and / or the adhesive coating is applied may already be coated with an initial coating on which the coating according to the invention is superimposed. It can thus be a sheet having a coating bitumen type.

 The present invention also relates to articles (ribbons for example) comprising a complex according to the invention. It may especially be labels, adhesive sheets or adhesive tapes.

 A second aspect of the present invention relates to the use of an additive as defined above for the stabilization of the release force of a silicone / adhesive complex as defined above by introducing said additive into said adhesive coating .

 The invention also extends to the use of an adhesive coating as defined above to form a silicone / adhesive complex according to the invention, characterized in that it contains at least one compound as defined above. as an additive for the stabilization of the release force at a silicone / complex interface.

 The following examples are presented for illustrative and not limiting of the present invention.

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Method
The compositions which are described in the following examples, based on structural silicones (SI)

Two polymers have been chosen more particularly:
They respond to the average structure of random distribution as
A, / a = 80; b = 7
A2 / a = 222; b = 3
These silicones are photopolymerized, after application, on a polypropylene film of 50 g / m 2. A weight of deposited silicone which is between 0.5 and 1 g / m 2 on plastic and 1 to 2 g / m 2 on paper is applied using a coating head composed of five rollers. The applied product is then exposed under ultraviolet irradiation at a running speed which varies between 50 and 1000 m / min, preferably greater than 100 m / min and in the presence of mercury vapor lamps sold by the company Fusion Power 120 W / cm or 240 W / cm and called H +, in preference to the nature of the irradiation, which is mainly emitted between 200 and 300 m. The number of lamps used depends on the width of the width.

A lamp occupies a width of 20 cm.

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 The number of lamps used depends on the speed of the process.

A lamp of 120 W / cm is sufficient to polymerize at 100 m / min. Two lamps will be effective for a process of 200 m / min or more.

After exposure under ultraviolet light, the coatings are perfectly dry and a 50% acrylic adhesive is applied to the water, the base polymer of which has the following composition:
P1:> 70% butyl acrylate and <25% ethyl-2 hexyl acrylate
P2:> 80% in ethyl-2 hexyl acrylate and <10% in methyl methacrylate.

 This application is carried out either directly online (10 to 20 g / m2 dry) on an in-line or off-line adhesive machine, after less than five minutes, after crosslinking of the functional silicones.

 The adhesive is then heated between 100.degree. C. and 150.degree. C., preferably 100.degree. C., for less than 2 minutes in order to remove water from the adhesive, which is then transferred using a transfer cylinder. on a paper or plastic medium.

 The peeling forces of the various complexes obtained are measured, after storage for 20 h at 20 ° C., according to a standardized test (FINAT3), under a force of 70 g / cm 2, with a peel rate of 300 mm / min and after 20 hours at 70 C (FINA 10), simulating aging for 3 and 6 months at 20 C under pressure conditions of 70 g / cm 2.

Examples - 1- 2
Use of additives added to 0.45% in the adhesive based on the polymer P1 used without tackifier.

 The release forces of the in-line applied adhesive were measured on the silicone deposited at a rate of 0.8 g / m 2 on a polypropylene film and then dried at a rate of 200 m / min, using two lamps. Fusion 120

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dans l'isopropanol et cinq parties du polymère A2. L'ensemble est agité vigoureusement avant utilisation sous forme de bain d'enduction sur des rouleaux inducteurs. W / cm (H +). The silicone formulation is obtained by mixing 95 parts of the polymer A1 with 2.5 parts of an 18% solution of the photoinitiator Pl1

in isopropanol and five parts of the polymer A2. The whole is stirred vigorously before use in the form of a coating bath on induction rollers.

 The adhesive used, applied to the photocrosslinked silicone is based on the polymer P., and is marketed under the name RHODOTAK 315P. It is applied in emulsion at approximately 50% solids content (15-20 g / m2). The control test comprising no additive in the adhesive is noted Additive 0. All the other additives used in the following examples are, at a rate of 0.45%, added directly into the emulsion adhesive except potash that changes the pH of the adhesive between 4 and 6 and can not be added to more than 1000 ppm.

 The results obtained are shown in Table I below.

Table 1

<Tb>
<tb> Example <SEP> Additive <SEP> FINAT3 <SEP> 7 <SEP> days <SEP> to <SEP> 70 C
<tb> 0.45% <SEP> in <SEP> weight <SEP> (g / cm) <SEP> (g / cm)
<tb> Control <SEP> 1 <SEP> Additive <SEP> 0 <SEP> 2,59 <SEP> 100
<tb> 1 <SEP> KOAc <SEP> 2.59 <SEP> 19.29
<tb> 2 <SEP> Ca <SEP> (OAc) 2 <SEP> 3.70 <SEP> 20.47
<tb> Control <SEP> 3 <SEP> KOH <SEP> (500 <SEP> ppm) <SEP> 2.48 <SEQ> 86.61
<tb> Control <SEP> 2 <SEP> AcOH <SEP> 2.59 <SEP> 96.06
<Tb>

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Examples 3-8 Examples with P, or P2 used with or without tackifier (25% Tacolyn 3179).

 The polymer P2 used is composed mainly of basic units derived from the polymerization of 2-ethyl acrylate, and marketed by BASF under the name Acronal V210. The silicone coating is applied in the same manner as in the previous examples.

 The adhesive is similarly dried at 100 ° C. in an oven before being transferred to a self-adhesive label paper.

 The results obtained are shown in Table II below.

Table II

<Tb>
<tb> Example <SEP> Adhesive <SEP> Additive <SEP> FINAT3 <SEP> 7days at 70 C
<tb> 0.45% <SEP> in <SEP> weight <SEP> (g / cm) <SEP> (g / cm)
<tb> 3 <SEP> P2 <SEP> No <SEP> of additive <SEP> 2.48 <SEP> 9.84
<tb> 4 <SEP> P2 <SEP> tackified <SEP> No <SEP> of additive <SEP> 2.67 <SEP> 7.08
<tb> 5 <SEP> P2 <SEP> tackified <SEP> KOAc <SEP> 2.59 <SEP> 3.93
<tb> 6 <SEP> P1 <SEP> No <SEP> of additive <SEP> 2.48 <SEP> 100
<tb> 7 <SEP> P1 <SEP> tackified <SEP> No <SEP> of additive <SEP> 3.70 <SEP> 74.80
<tb> 8 <SEP> P1 <SEP> tackified <SEP> KOAc <SEP> 2.44 <SEP> 11.81
<Tb>

Examples 9-17
Examples 1 and 2 are repeated with the polymer P1 by varying the amount and nature of the additives used. The silicone is applied to a polyester film at a rate of 0.8 g / m 2 and the silicone is dried at 100 m / min with 1 Fusion A lamp of 120 W / cm.

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Table III

<Tb>
<tb> Example <SEP> Additive <SEP> Weight <SEP> additive <SEP> Finat3 <SEP> Finatl0 <SEP> 7 <SEP> days <SEP> to <SEP> 70 C <SEP>
<tb>%
<tb> (g / cm) <SEP> (g / cm) <SEP> (g / cm)
<tb> 9 <SEP> 0 <SEP> 0 <SEP> 2.36 <SEP> 29.17 <SEP> 64.80
<tb> 10 <SEP> CF, COOK <SEP> 0.125 <SEP> 2.36 <SEP> 8.26 <SEP> 20.78
<tb> 11 <SEP> CF, COOK <SEP> 0.25 <SEP> 2.36 <SEP> 8 <SEP> 58 <SEP> 25.39
<tb> 12 <SEP> CF, COOK <SEP> 0.5 <SEP> 2.36 <SEP> 3.34 <SEP> 14.33
<tb> 13 <SEP> CF, COOK <SEP> 1 <SEP> 2.36 <SEP> 7.79 <SEP> 18 <SEP> 89 <SEP>
<tb> 14 <SEP> HK, PO, <SEP> 0.125 <SEP> 2.36 <SEP> 3.97 <SEP> 11.53
<tb> 15 <SEP> HK, PO. <SEP> 0.25 <SEP> 2.36 <SEP> 6 <SEP> 85 <SEP> 27.55
<tb> 16 <SEP> HK, PO, <SEP> 0.5 <SEP> 2.36 <SEP> 3.34 <SEP> 17.32
<tb> 17 <SEP> HK2PO4 <SEP> 1 <SEP> 2.36 <SEP> 7.48 <SEP> 15.90
<Tb>

Examples 18-26
Examples 9 to 17 are repeated by varying the support on which the silicone is applied at a rate of 1.5 g / m 2.

 A coated paper marketed by the company LOHTAN is used.

Table IV

<Tb>
<tb> Example <SEP> Additive <SEP> Weight <SEP> of additive <SEP> Finat3 <SEP> FinatlO <SEP> 7 <SEP> days <SEP> to <SEP> 70 C <SEP>
<Tb>

/cm /cm (g/cm) (g/cm) (g/cm)

/ cm / cm (g / cm) (g / cm) (g / cm)

<Tb>
<tb> 18 <SEP> 0 <SEP> 0 <SEP> 2.36 <SEP> 37.40 <SEP> 95.59
<tb> 19 <SEP> CF, COOK <SEP> 0.125 <SEP> 2.36 <SEP> 7.77 <SEP> 95.59
<tb> 20 <SEP> CF, COOK <SEP> 0.25 <SEP> 2.36 <SEP> 14.40 <SEP> 62.63
<tb> 21 <SEP> CF.COOK <SEP> 0.5 <SEP> 2.36 <SEP> 6.61 <SEP> 18.50
<tb> 22 <SEP> CF.COOK <SEP> 1 <SEP> 2.36 <SEP> 7.16 <SEP> 34.92
<tb> 23 <SEP> HK, PO <SEP> 0.125 <SEP> 2.36 <SEP> 6.10 <SEP> 42.36
<tb> 24 <SEP> HK2PO4 <SEP> 0.25 <SEP> 2.36 <SEP> 6.35 <SEP> 53.89
<tb> 25 <SEP> HK2PO4 <SEP> 0.5 <SEP> 2.36 <SEP> 5.39 <SEP> 31.06
<tb> 26 <SEP> HK2PO4 <SEP> 1 <SEP> 2.36 <SEP> 9.01 <SEP> 16.27
<Tb>

Claims (23)

A silicone / non-stick adhesive complex comprising at least one silicone coating applied to a first support and an adhesive coating applied to a second support, characterized in that said adhesive coating comprises as an additive intended to stabilize over time the detachment force of a silicone / adhesive interface at least one salt of a group IA or IIA element of the periodic classification with a compound chosen from: - carboxylates of formula OCORe, with R representing a linear, branched alkyl radical or cyclic, saturated, unsaturated or aromatic C1 to C12 and optionally substituted by one or more halogen atoms, - fluorophosphates such as potassium hexafluorophosphate, - fluorosulfonates such as potassium trifluoromethanesulfonate, and - esters or salts of phosphoric acid such as K3PO4, K4P2O7, (Me3SiO) n-POK with n = 1 or 2, HK2PO4, KH2PO4. O # 2. Complex according to claim 1, characterized in that the first support and the second support consist of two different materials and arranged so that the silicone coating of the first support is in contact with the adhesive coating of the second support.  3. Complex according to claim 1, characterized in that the first support and the second support are respectively constituted by each of the two faces of the same material.  4. Complex according to one of claims 1 to 3, characterized in that the additive is selected from (C2H5) (C4H9) CHCOOK, (CH3) (CH2) 7CH = CH (CH2) 7COOK, (CH3COO) 2Ca, CH3-COOK, (CH3O) 2P (O) CH2COOK, CF3COOK and HK2PO4. <Desc / Clms Page number 29>  5. Complex according to one of claims 1 to 4, characterized in that the additive is present in the adhesive up to 5% by weight.  6. Complex according to claim 5, characterized in that the amount of additive varies between 0.01% and 1% by weight.  7. Complex according to one of the preceding claims, characterized in that the adhesive coating is derived from a pressure sensitive adhesive emulsion, PSA.  8. Complex according to claim 7, characterized in that the pressure-sensitive adhesive emulsions are obtained by polymerization mainly of acrylate monomers present in a proportion of 50 to approximately 90% and preferably in a proportion of 80 to 99% by weight and the optionally copolymerizable radical monomers.  9. Complex according to claim 8, characterized in that the monomers are chosen from the group consisting of: - (meth) acrylic esters such as esters of acrylic acid and methacrylic acid with hydrogenated C1-C12 alkanols or fluorinated, preferably C1-C8, especially methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, acrylate 2- ethylhexyl, tert-butyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, isooctyl acrylate, decyl acrylate, dodecyl, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate; vinyl nitriles, especially those having from 3 to 12 carbon atoms, such as in particular acrylonitrile and methacrylonitrile; vinyl esters of carboxylic acid such as vinyl acetate, vinyl versatate, vinyl propionate, <Desc / Clms Page number 30>  unsaturated ethylenic mono- and dicarboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid and the mono- and di-alkyl esters of these mono- and di- with alkanols having preferably 1 to 8 carbon atoms and their N-substituted derivatives, - amides of unsaturated carboxylic acids such as acrylamide, methacrylamide, N-methylolacrylamide or methacrylamide, N-alkylacrylamides, - ethylenic monomers comprising a sulphonic acid group and its alkali or ammonium salts, for example vinylsulphonic acid, vinylbenzenesulphonic acid, alpha-acrylamido methylpropanesulphonic acid, 2-sulphoethylene-methacrylate, ethylenic unsaturated monomers comprising a secondary, tertiary or quaternary amino group, or a heterocyclic group containing nitrogen such as for example vinylpyridines, vinylimidazole, (meth) acrylates aminoalkyl and aminoalkyl (meth) acrylamides such as dimethylaminoethyl acrylate or dimethylaminoethyl methacrylate, ditertiobutylaminoethyl acrylate or ditertiobutylaminoethyl methacrylate, dimethylaminomethyl acrylamide or dimethylaminomethyl methacrylamide, zwitterionic monomers such as, for example, sulfopropyl (dimethyl) acrylate aminopropyl, ethylenic monomers carrying a sulfate group, ethylenic monomers carrying phosphate or phosphonate functions, and mixtures thereof. <Desc / Clms Page number 31>  10. Complex according to one of claims 8 to 9, characterized in that the monomers are chosen from 2-ethylhexyl acrylate, butyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, isooctyl acrylate, decyl acrylate, isobutyl acrylate, dodecyl acrylate, methacrylic acid, acrylic acid, itaconic acid, maleic acid and acrylamide.  11. Complex according to one of the preceding claims, characterized in that the silicone coating derives from the polymerization and / or crosslinking of monomers, oligomers and / or polyorganosiloxane polymers with organofunctional groups.  12. Complex according to claim 11, characterized in that the monomers, oligomers and / or polymers of polyorganosiloxane nature have, as organofunctional groups, epoxy groups, oxetanes, dioxolane and / or alkenyl ethers.  13. Complex according to claim 11 or 12, characterized in that the monomers, oligomers and / or polyorganosiloxane polymers containing organofunctional groups consist of units of formula (1) and terminated by units of formula (II) or cyclic units consisting of of formula (1) represented below: R1 R1 - (Si-O -) - (I) Z-Si-O- (II) In which: the symbols R 1 and R 2 are identical or different and represent: a linear or branched alkyl radical containing 1 to 8 carbon atoms, optionally substituted with at least one halogen, <Desc / Clms Page number 32> 12 carbon atoms, optionally substituted on the aryl part by halogens, alkyls and / or alkoxyls containing 1 to 3 carbon atoms, - the symbols Z are similar or different and represent: a group R1 and / or R2, a hydrogen radical, and / or a crosslinkable organofunctional group, such as oxetane, dioxolane, epoxy and / or alkenyl ether, connected to the silicon of the polyorganosiloxane via a divalent radical containing from 2 to 20 carbon atoms and which may contain at least a heteroatom, with at least one of the symbols Z representing a crosslinkable functional organic group. 14 carbon atoms and an aryl part containing between 6 and  a cycloalkyl radical containing between 5 and 8 ring carbon atoms, optionally substituted, an aryl radical containing between 6 and 12 carbon atoms which may be substituted, an aralkyl part having an alkyl part containing between 5 and  14. Complex according to claim 13, characterized in that the divalent radicals connecting an organofunctional group of the epoxy type are chosen from:

<Desc / Clms Page number 33>  and the organofunctional groups of the alkenyl ether type are chosen from: - (O) n '- (CH2) n "-O-CH = CH2; - (O) n' - (CH2) n" -R3-O-CH = CH2 ; In which: # n 'represents 0 or 1 and n "an integer between 1 and 5 # R3 represents: or C 1 -C 12 cyclic, optionally substituted, - or a C 5 -C 12 arylene radical, preferably phenylene, optionally substituted, preferably with one to three C 1 -C 6 alkyl groups, # R 4 represents a linear or branched alkyl radical; C1-C6.

 15. Complex according to one of claims 1 to 10, characterized in that the silicone coating derives from the crosslinking and / or polymerization of polyorganosiloxanes A having by molecule at least one reactive radical SiH and free of silicon atoms bound to more of two hydrogen atoms and B compounds selected from polyorganosiloxanes and having per molecule at least one unsaturated aliphatic reactive group and / or at least one reactive function. <Desc / Clms Page number 34>  16. Complex according to claim 15, characterized in that the compounds A are chosen from polyorganohydrogensiloxanes comprising: * units of the following formula: HaWbSiO4- (a + b) (1) 2 in which: - the symbols W are similar or different and represent a monovalent hydrocarbon group selected from (cyclo) alkyl groups having 1 to 18 carbon atoms inclusive and aryl or aralkyl groups C6-C12 'and - a is 1 or 2, b is 0,1 or 2, with the sum (a + b) having a value between 1 and 3.  17. Complex according to claim 15 or 16, characterized in that the organopolysiloxanes A are chosen from: - dimethylpolysiloxanes with hydrogenodimethylsilyl ends, - dimethylhydrogénométhylpolysiloxane copolymers with trimethylsilyl ends, - dimethylhydrogénométhylpolysiloxane copolymers with hydrogenodimethylsilyl ends, - hydrogénomethylpolysiloxanes with trimethylsilyl ends cyclic hydrogen methylpolysiloxanes.  18. Complex according to one of claims 15 to 17, characterized in that the organopolysiloxanes B are polyorganosiloxanes comprising similar or different units of formula: W'dXeYfSiO4- (d + e + f) (3) 2 <Desc / Clms Page number 35>  in which: the symbols W 'correspond to the same definition as that given in claim 16, the symbols X are similar or different and represent a hydrogen atom or a reactive function, preferably epoxyfunctional, connected to silicon by a radical; divalent, optionally comprising at least one heteroatom, the Y symbols are similar or different and represent a linear or branched C 1 -C 12 alkenyl residue, and having at least one ethylenic unsaturation at the chain end and / or in the chain and optionally at the end of the chain. minus one heteroatom; d, e and f are 0, 1, 2 or 3; - d + e + f = 0, 1, 2 or 3; with the rate of SiO4 / 2 units being less than 30 mol%.  19. Complex according to one of claims 15 to 18, characterized in that the silicone matrix comprises compounds A and compounds B in an amount such that the molar ratio Si-H / unsaturated group and / or reactive function, for example epoxy is between 0.4 and 10, and preferably between 1 and 4.  20. Complex according to one of claims 15 to 19, characterized in that the silicone matrix further comprises a platinum thermosensitive complex type catalyst.  21. Article characterized in that it comprises a complex according to one of the preceding claims.  22. Article according to claim 21, characterized in that it is labels, adhesive sheets or adhesive tapes. <Desc / Clms Page number 36>  23. Use in an adhesive coating as defined in claims 1 and 7 to 11 and for forming a silicone / adhesive complex according to one of claims 1 to 20 of a compound according to one of claims 1 to 6 for stabilize over time the peel force of a silicone / adhesive interface.