Medical silicone pressure sensitive adhesive composition

Abstract

The invention relates to a medical organic silicon pressure-sensitive adhesive composition. The present invention relates to a composition comprising at least one organopolysiloxane A comprising at least two C2-C6 alkenyl groups each bonded to a silicon atom per molecule, at least one organopolysiloxane resin B comprising OH groups bonded to a silicon atom, at least one organopolysiloxane chain extender CE having exactly two terminal hydrogen atoms bonded to a silicon atom, and at least one organopolysiloxane chain extender E having exactly two terminal hydrogen atoms bonded to a silicon atom, the invention relates to a composition comprising at least one organopolysiloxane A, CE and XL, optionally at least one organopolysiloxane crosslinking agent XL having at least three hydrogen atoms bonded to silicon atoms, at least one hydrosilylation catalyst D, at least one solvent E and optionally at least one hydrosilylation inhibitor F, where the organopolysiloxanes A, CE and XL are selected such that the molar ratio RHAlk is 2 to 5 and the ratio nHXL / nHCE is less than 0.10.

Description

Technical Field

[0001] The field of the present invention is the field of medical pressure-sensitive adhesives (PSA). In particular, the present invention relates to a medical silicone pressure-sensitive adhesive composition, a method for coating a substrate by using the medical silicone pressure-sensitive adhesive composition, and also to a skin-adhesive article obtainable according to the method. Background Art

[0002] PSA is an abbreviation of the term "pressure sensitive adhesive", which is well known in the art and is widely used in various applications, especially in medical applications. Currently in the medical market, most skin contact products such as tapes, patches and bandages are prepared by acrylic-based PSAs. However, acrylic-based PSAs have some disadvantages, such as poor perspiration (water) resistance, poor biocompatibility, and high sensitization rate to human skin, especially to infants and children.

[0003] Silicone-based PSAs are also widely used in medical applications for application against or in contact with the skin. Silicone-based PSAs are able to adhere to surfaces simply by contact or under the action of light pressure. It has significant advantages over acrylic-based PSAs. Silicone-based PSAs show favorable properties in medical applications due to their air permeability, water resistance, low irritation, and biocompatibility. For example, silicone-based PSAs are suitable for the enhanced requirements of new medical applications due to their biocompatibility and their permeability, which enables the diffusion of oxygen, carbon dioxide, and water vapor, which makes them very suitable for medical applications requiring enhanced ventilation.

[0004] WO 2017 / 158249 A1 and WO 2017 / 051083 disclose skin-adhesive silicone gels. The silicone gels lack adhesion to wet skin due to their inherent properties and are therefore advantageous for wound care applications because they can avoid secondary damage to the wound when using a dressing. However, for medical materials that are non-traumatically attached to the skin, a humid environment or sweating often causes the gel to lose its adhesiveness and then fall off.

[0005] US 2007 / 0202245 A1 discloses a method for improving the adhesion of silicone gels to medical substrates by including a hydroxy-substituted siloxane resin in the gel formulation. However, the improved formulation disclosed in this document is still a silicone gel.

[0006] WO 2020 / 099999 A1 describes a medical silicone pressure-sensitive adhesive. The silicone composition is cured by a polycondensation reaction: the condensation product is formed by the reaction between a polyorganosiloxane containing terminal hydroxyl groups and a silicate resin, and then a non-reactive polyorganosiloxane is added. In the subsequent tape production process, an electron beam is used to promote the crosslinking of the non-reactive polyorganosiloxane to form a pressure-sensitive adhesive layer on the substrate. The production process of this PSA is complicated, and the control of the condensation reaction conditions has a great influence on the product quality.

[0007] Therefore, there is a continuing need to obtain a silicone-based pressure-sensitive adhesive composition having an excellent combination of properties suitable for medical applications. Summary of the invention

[0008] Summary of the Invention

[0009] The present invention has solved the problems of the prior art.

[0010] The present invention relates to a medical organosilicon pressure-sensitive adhesive composition, which comprises:

[0011] at least one organopolysiloxane A comprising, per molecule, at least two C2-C6 alkenyl groups each bonded to a silicon atom, wherein the organopolysiloxane A is an organopolysiloxane gum,

[0012] - at least one organopolysiloxane resin B comprising one or more OH groups bonded to silicon atoms,

[0013] - at least one organopolysiloxane chain extender CE having exactly two terminal hydrogen atoms bonded to silicon atoms,

[0014] - optionally, at least one organopolysiloxane crosslinker XL having at least three hydrogen atoms bonded to silicon atoms,

[0015] - at least one hydrosilylation catalyst D,

[0016] - at least one solvent E, and

[0017] - optionally, at least one hydrosilylation inhibitor F,

[0018] wherein the organopolysiloxanes A, CE and XL are selected so that the molar ratio RHAlk=tH / tAlk is 2 to 5; and nH XL / nH CE Ratio is less than 0.10, where:

[0019] -tH = the number of moles of hydrogen atoms directly bonded to the silicon atoms of the organopolysiloxanes CE and XL;

[0020] -tAlk=the number of moles of alkenyl groups directly bonded to the silicon atoms of the organopolysiloxane A;

[0021] -nH XL = the number of moles of hydrogen atoms directly bonded to the silicon atoms of the organopolysiloxane XL;

[0022] -nH CE = the number of moles of hydrogen atoms directly bonded to the silicon atoms of the organopolysiloxane CE.

[0023] The medical silicone pressure-sensitive adhesive composition according to the present invention is a precursor of the silicone pressure-sensitive adhesive G and can be cross-linked by hydrosilylation.

[0024] The present invention also relates to a method for manufacturing a skin adhesive article, comprising the steps of: continuously or discontinuously coating the medical organosilicon pressure-sensitive adhesive composition as defined above on at least one of the two faces of a substrate, and crosslinking the medical organosilicon pressure-sensitive adhesive composition to form an organosilicon pressure-sensitive adhesive G. Another object of the present invention is a skin adhesive article comprising a substrate, the substrate being continuously or discontinuously coated on at least one of its two faces with an organosilicon pressure-sensitive adhesive G obtained by crosslinking the medical organosilicon pressure-sensitive adhesive composition as defined above.

[0025] It has been found that medical silicone pressure-sensitive adhesives providing excellent properties suitable for medical applications can be obtained from silicone pressure-sensitive adhesive compositions as defined above which contain no or very low amounts of organopolysiloxane crosslinkers XL at a molar ratio RHAlk of 2 to 5.

[0026] Suitable properties for medical silicone pressure sensitive adhesives are, for example, an excellent combination of easy tearability, no visible residue on the skin, good anchorage on the substrate, good peel adhesion, good tack, suitable peel force, and acceptable repositioning properties.

[0027] Detailed description of the invention

[0028] All viscosities considered in this description correspond to the amount of "Newtonian" dynamic viscosity at 25° C., ie the dynamic viscosity measured in a manner known per se using a Brookfield viscometer at a shear rate gradient low enough to make the measured viscosity independent of the rate gradient.

[0029] The consistency or penetration of the glue is typically determined at 25°C by a PNR12 type penetrometer or an equivalent model that enables the application of a cylindrical head to the sample under standardized conditions. The penetration of the glue refers to the depth of penetration of the calibrated cylinder into the sample in one minute, expressed in tenths of a millimeter. For example, the following method is given: the glue sample is introduced into an aluminum cup with a diameter of 40 mm and a height of 60 mm. The cylindrical head made of bronze or brass has a diameter of 6.35 mm and a height of 4.76 mm and is carried by a metal rod 51 mm long and 3 mm in diameter compatible with the penetrometer. This rod is weighted with an additional load of 100 g. The total weight of the assembly is 151.8 g, of which 4.3 g is the cylindrical part and its supporting rod. The cup containing the glue sample is placed in a constant temperature bath set at 25°C ± 0.5°C for at least 30 minutes. The measurement is carried out according to the manufacturer's instructions. The value of the depth (V) expressed in tenths of a millimeter and the time (t) expressed in seconds to reach this depth is displayed on the machine. The penetration is equal to 60 V / t expressed in tenths of a millimeter per minute.

[0030] In this specification, to describe the polyorganosiloxanes, the nomenclature known in the silicone art is used, which uses the following letters to describe the siloxy units: M, D, T and Q. The letter M represents a polyorganosiloxane having the formula (R 1 )3SiO 1 / 2 The letter D represents a difunctional unit (R 1 )2SiO 2 / 2 , wherein the silicon atom is connected to two oxygen atoms. The letter T represents a compound having the formula (R 1 )SiO 3 / 2 The letter Q represents a trifunctional unit having the formula SiO 4 / 2 A trifunctional unit in which a silicon atom is connected to four oxygen atoms. Symbol R 1 The M, D, T units may be functionalized. Therefore, when referring to the M, D, T units, the specific groups must be specified.

[0031] Component A may be at least two C2-C6 alkenyl-substituted silicone polymers, which serve as a backbone in the composition.

[0032] Preferably, the at least one organopolysiloxane A may comprise:

[0033] (i) at least two siloxy units of formula (A1):

[0034] (Y) a (Z) b SiO (4-(a+b)) / 2 (A1)

[0035] in:

[0036] -Y represents a monovalent group containing 2 to 6 carbon atoms having at least two alkenyl groups;

[0037] -Z represents a monovalent group containing 1 to 20 carbon atoms and not containing an alkenyl group;

[0038] -a and b represent integers, a is 1, 2 or 3, b is 0, 1 or 2, and (a+b) is 1, 2 or 3;

[0039] (ii) and may optionally contain further siloxy units of formula (A2):

[0040] (Z) c SiO (4-c) / 2 (A2)

[0041] in:

[0042] -Z has the same meaning as above, and

[0043] -c represents an integer, which is 1, 2, or 3.

[0044] According to the present invention, in the definition of the organopolysiloxane A, in formula (A1), the symbol a may preferably be equal to 1 or 2, and even more preferably equal to 1. Furthermore, in formula (A1) and in formula (A2), the symbol Z may preferably represent a monovalent group selected from the following: an alkyl group containing 1 to 8 carbon atoms (optionally substituted by at least one halogen atom), and a C6-C 10 Aryl group. Z may advantageously represent a monovalent group selected from the group consisting of methyl, ethyl, propyl, 3,3,3-trifluoropropyl, xylyl, tolyl and phenyl. Furthermore, in formula (A1), symbol Y may advantageously represent a group selected from the group consisting of vinyl, propenyl, 3-butenyl and 5-hexenyl. Preferably, symbol Y is vinyl and symbol Z is methyl.

[0045] The organopolysiloxane gum A has a linear structure. It can basically be composed of the following units:

[0046] - Selected from the formula (Y)2SiO 2 / 2 、(Y)(Z)SiO 2 / 2 and (Z)2SiO 2 / 2 siloxy units "D" of units; and

[0047] - Selected from the formula (Y)3SiO 1 / 2 、(Y)2(Z)SiO 1 / 2 、(Y)(Z)2SiO 1 / 2 and (Z)3SiO 2 / 2 The siloxy unit "M" of the unit,

[0048] - In these formulae, the symbols Y and Z are as defined above.

[0049] Preferably, the linear organopolysiloxane A has a degree of polymerization of 2,000 to 10,000, more preferably 2,000 to 8,000 and more preferably 2,000-5,000.

[0050] As examples of the unit “D”, mention may be made of dimethylsiloxy, methylphenylsiloxy, methylvinylsiloxy, methylbutenylsiloxy, methylhexenylsiloxy, methyldecenylsiloxy and methyldecadienylsiloxy groups.

[0051] As examples of the unit "M", mention may be made of trimethylsiloxy, dimethylphenylsiloxy, dimethylvinylsiloxy and dimethylhexenylsiloxy groups.

[0052] The organopolysiloxane A may be a polymer preferably having a weight average molecular weight Mw of 260,000 g / mol to 1,000,000 g / mol, preferably 400,000 g / mol to 1,000,000 g / mol, and more preferably 400,000 g / mol to 900,000 g / mol.

[0053] As examples of useful organopolysiloxanes A, mention may be made of:

[0054] - polydimethylsiloxanes having dimethylvinylsilyl terminal ends;

[0055] - poly(methylphenylsiloxane-co-dimethylsiloxane) having dimethylvinylsilyl terminal ends;

[0056] - poly(vinylmethylsiloxane-co-dimethylsiloxane) having dimethylvinylsilyl terminal ends;

[0057] - Poly(dimethylsiloxane-co-vinylmethylsiloxane) having trimethylsilyl termini.

[0058] Particularly advantageous are organopolysiloxanes A which are polydimethylsiloxanes containing dimethylvinylsilyl terminal groups and have a weight average molecular weight Mw of 260,000 to 1,000,000 g / mol, preferably 400,000 to 900,000 g / mol. Particularly advantageous organopolysiloxanes A are of the formula M Vi D a M Vi Of those, among which:

[0059] -M Vi=Siloxy unit of the formula: (vinyl)(CH3)2SiO 1 / 2

[0060] - D = siloxy unit of the formula: (CH3)2SiO 2 / 2 ,as well as

[0061] - a is a number between 2000 and 6000, and preferably between 3000 and 5500.

[0062] Based on the total amount of components A+B+XL+CE, the organopolysiloxane A can be used in an amount of 15% to 45% by weight, preferably 20% to 40% by weight. According to one embodiment, based on the total weight of the organopolysiloxane A, the organopolysiloxane A has an alkenyl content of 0.001% to 0.5% by weight, preferably 0.005% to 0.025% by weight, more preferably 0.008% to 0.018% by weight.

[0063] Preferably, the organopolysiloxane A can be selected from dimethylvinyl-terminated polydimethylsiloxane, dimethylvinyl-terminated polydimethylmethylvinylsiloxane, trimethyl-terminated polydimethylmethylvinylsiloxane, and more preferably dimethylvinyl-terminated polydimethylsiloxane.

[0064] According to one embodiment, the organopolysiloxane A is an organopolysiloxane gum having a consistency of 200 to 2000 mm / 10, preferably 300 to 1800 mm / 10, more preferably 500 to 1500 mm / 10 at 25°C.

[0065] According to one embodiment, organopolysiloxane A is an organopolysiloxane gum having a weight average molecular weight Mw of 260,000 to 1,000,000 g / mol, preferably 400,000 to 1,000,000 g / mol and more preferably 400,000 to 900,000 g / mol. The weight average molecular weight Mw is determined by gel permeation chromatography using polystyrene as a standard.

[0066] According to one embodiment, the organopolysiloxane A is an organopolysiloxane gum having a viscosity greater than 600,000 mPa.s at 25°C, preferably greater than 1,000,000 mPa.s at 25°C.

[0067] According to one embodiment, the medical silicone pressure-sensitive adhesive composition according to the present invention further comprises at least one organopolysiloxane A'', which is an oil having a dynamic viscosity of 10 to 500,000 mPa.s at 25° C., preferably 100 to 100,000 mPa.s at 25° C., more preferably 10,000 to 100,000 mPa.s at 25° C. The organopolysiloxane A'' may be linear or branched, and may have an alkenyl content of 0.05 to 0.5% by weight based on the total weight of component A''.

[0068] The organopolysiloxane resin B containing hydroxyl groups bonded to Si atoms may be selected from conventional organopolysiloxane resins, among which mention may be made of organosilicon resins prepared by co-hydrolysis and co-condensation of chlorosilanes selected from the following: 2 )3SiCl、(R 2 )2Si(Cl)2、R 2 These resins are well-known and commercially available branched organopolysiloxane oligomers or polymers. They have in their structure at least two selected from the group consisting of formula (R 2 )3SiO 1 / 2 (M unit), (R 2 )2SiO 2 / 2 (D unit), R 2 SiO 3 / 2 (T unit) and SiO 4 / 2 (Q units), wherein at least one of these units is a T unit or a Q unit. The group R 2 The distribution is such that each silicon atom in the resin contains about 0.8-1.8 groups R 2 In addition, these resins are not fully condensed and contain OH groups. 2 are identical or different and are selected from C1-C6 linear or branched alkyl, C2-C4 alkenyl, phenyl, 3,3,3-trifluoropropyl. 2 As examples of radicals, methyl, ethyl, isopropyl, tert-butyl and n-hexyl may be mentioned, and as alkenyl groups vinyl or allyl may be mentioned. Preferably, the radical R 2 is a methyl group or a hydroxyl group.

[0069] According to a particular embodiment, the organopolysiloxane resin B comprising hydroxyl groups is chosen from:

[0070] a) MQ (OH) A hydroxylated silicone resin comprising siloxy units M and Q of the formula (OH) Copolymers:

[0071] - M=R 3 R 4 R 5 SiO 1 / 2 ,and

[0072] -Q (OH) =(OH)SiO 3 / 2 ,

[0073] Wherein siloxy units Q=SiO are optionally present 4 / 2 ;

[0074] b) MD Vi Q (OH) A hydroxylated silicone resin comprising siloxy units M, D Vi and Q (OH) Copolymers:

[0075] - M=R 3 R 4 R 5 SiO 1 / 2 ,

[0076] -D Vi =(Vi)(R 3 )SiO 2 / 2 ,and

[0077] -Q (OH) =(OH)SiO 3 / 2 ,

[0078] Wherein siloxy units Q=SiO are optionally present 4 / 2 ;

[0079] c) MM Vi Q (OH) A hydroxylated silicone resin comprising siloxy units M, M Vi and Q (OH) Copolymers:

[0080] - M=R 3 R 4 R 5 SiO 1 / 2 ,

[0081] -M Vi =(Vi)(R 3 )(R 4 )SiO 2 / 2 ,and

[0082] -Q (OH) =(OH)SiO 3 / 2 ,

[0083] Wherein siloxy units Q=SiO are optionally present 4 / 2 ;

[0084] d) MDT (OH) T-type hydroxylated silicone resin, which comprises siloxy units M, D, T (OH) Copolymers with T:

[0085] - M=R 3 R 4 R 5 SiO 1 / 2 ,

[0086] - D=R 3 R 4 SiO 2 / 2 ,

[0087] -T (OH) =(OH)R 3 SiO 2 / 2 ,

[0088] - T=R 3 SiO 3 / 2 ,as well as

[0089] e) DT (OH) T-type hydroxylated silicone resin, which comprises siloxy units D, T (OH) Copolymers with T:

[0090] - D=R 3 R 4 SiO 2 / 2 ,

[0091] -T (OH) =(OH)R 3 SiO 2 / 2 ,

[0092] - T=R 3 SiO 3 / 2 ,and

[0093] In the formula, the symbol Vi = vinyl group, the symbol R 3 , R 4 and R 5 Independently selected from:

[0094] - has a linear or branched alkyl group containing 1 to 8 carbon atoms and optionally substituted by one or more halogen atoms, and is preferably selected from methyl, ethyl, isopropyl, tert-butyl and n-hexyl, and

[0095] - an aryl or alkylaryl group having 6 to 14 carbon atoms, inclusive, and preferably selected from phenyl, xylyl and tolyl.

[0096] According to a preferred embodiment, as an example of the organopolysiloxane resin B, at least one selected from MQ resin, MDQ resin, DT resin and MDT resin may be mentioned, and the OH group may be carried by the Q and / or T unit.

[0097] According to another preferred embodiment, the organopolysiloxane resin B is MQ (OH) 、MQQ (OH) or MM Vi Q (OH) The present invention relates to a hydroxylated silicone resin of the type hydroxylated silicone resin of the present invention, and contains 0.1% to 4% by weight, preferably 0.3% to 2.0% by weight, more preferably 0.5% to 1.5% by weight of hydroxyl groups relative to the dry weight of the organopolysiloxane resin B. Preferably, the ratio of M units to Q units is 0.5 to 1.2, preferably 0.6 to 0.9. Component B may have a weight average molecular weight Mw of 3000 g / mol to 12000 g / mol, preferably 4000 g / mol to 11000 g / mol.

[0098] In the composition of the present invention, the organopolysiloxane resin B may be used as a tackifier.

[0099] The organopolysiloxane resin B may be used in an amount of 25 to 80% by weight, preferably 40 to 60% by weight, based on the total amount of components A+B+XL+CE.

[0100] Preferably, the weight ratio between component B and component A may be 0.8 to 2.5, preferably 1.0 to 2.0.

[0101] Component CE, also referred to as “chain extender” or simply “chain extender”, is an organopolysiloxane having exactly two terminal hydrogen atoms bonded to Si.

[0102] For example, the organohydrogensiloxane chain extender CE according to the present invention may comprise:

[0103] - two terminal siloxy units of formula (CE-1) which may be the same or different:

[0104] (H)(R 6 )2SiO 1 / 2 (CE-1)

[0105] in:

[0106] Symbol R 6 Corresponding to C1-C8 alkyl groups or C6-C 10an aryl group, and the symbol H represents a hydrogen atom;

[0107] - at least one siloxy unit of formula (CE-2):

[0108] (R 7 )2SiO 2 / 2 (CE-2)

[0109] The group R 7 Corresponding to C1-C8 alkyl groups or C6-C 10 Aryl groups,

[0110] Provided that the organopolysiloxane CE contains two hydrogen atoms each bonded to a different silicon atom per polymer, and preferably, the organopolysiloxane CE contains two siloxy units of formula (CE-1) and at least one siloxy unit of formula (CE-2) per polymer.

[0111] As examples of organopolysiloxanes CE, mention may be made of polydimethylsiloxanes comprising dimethylhydrogensilyl end groups having a dynamic viscosity at 25° C. of from 1 to 1000 mPa.s, preferably from 5 to 500 mPa.s, even more preferably from 5 to 300 mPa.s. Particularly advantageous organopolysiloxanes CE have the formula M H D x M H ,in:

[0112] -M H =Siloxy unit of the formula: (H)(CH3)2SiO 1 / 2

[0113] - D = siloxy unit of the formula: (CH3)2SiO 2 / 2 ,and

[0114] -x is an integer of 1-200, preferably 1-150, even more preferably 3-120.

[0115] Organopolysiloxane CE is described as a "chain extender" because, when the SiH reactive functional group is located at the chain end, it has the putative effect of increasing the mesh size of the network during the crosslinking process.

[0116] Component CE may have a dynamic viscosity at 25°C of 1 to 1000 mPa.s, preferably 5 to 500 mPa.s, more preferably 5 to 300 mPa.s.

[0117] Component CE may have a Si—H content of 0.2 to 10 wt %, preferably 0.3 to 8.0 wt %, more preferably 0.4 to 6.0 wt %, based on the total weight of component CE.

[0118] Preferably, the organopolysiloxane chain extender CE may be dimethyl hydrogen terminated polydimethylsiloxane.

[0119] The organopolysiloxane chain extender CE may be used in an amount of 5 to 20% by weight, based on the total amount of components A+B+XL+CE.

[0120] Unlike the chain extender CE, the component XL is also referred to as a "crosslinker", which is an organopolysiloxane having at least three hydrogen atoms bonded to Si. The organopolysiloxane crosslinker XL is an optional component of the composition according to the invention. When the organohydrogensiloxane crosslinker XL is present, it may be as disclosed below:

[0121] For example, the organohydrogensiloxane crosslinker XL according to the present invention may comprise:

[0122] - at least three siloxy units of formula (XL-1):

[0123] (H)(L) e SiO (3-e) / 2 (XL-1)

[0124] wherein the symbol H represents a hydrogen atom, and the symbol L represents an alkyl group having 1 to 8 carbon atoms, inclusive, or a C6-C 10 aryl, and the symbol e is equal to 0, 1 or 2; and

[0125] - Optionally, further siloxy units of formula (XL-2):

[0126] (L) g SiO (4-g) / 2 (XL-2)

[0127] wherein the symbol L represents an alkyl group having 1 to 8 carbon atoms, inclusive, or a C6-C 10 aryl, and the symbol g is equal to 0, 1, 2 or 3, and

[0128] Provided that the organopolysiloxane XL contains between 0.5 and 15.0 wt. % Si-H functional groups per polymer, preferably between 1.0 and 12.5 wt. % Si-H functional groups per polymer, and even more preferably between 1.5 and 10.0 wt. % Si-H functional groups per polymer.

[0129] As organopolysiloxanes XL having a crosslinking function and which can be used according to the invention, mention may be made of the formula M H D x D H w M H 、M H D x D H y M and MD x D z H Those of M, in these formulas:

[0130] -M H =Siloxy unit of the formula: (H)(CH3)2SiO 1 / 2

[0131] -D H =Siloxy unit of the formula: (H)(CH3)SiO 2 / 2

[0132] - D = siloxy unit of the formula: (CH3)2SiO 2 / 2 ,and

[0133] - M = siloxy unit of the formula: (CH3)3SiO 1 / 2

[0134] in

[0135] x is a number between 0 and 500, preferably between 2 and 250, more preferably between 5 and 80,

[0136] w is a number between 1 and 500, preferably between 1 and 250 or between 1 and 100, and even more preferably between 1 and 70;

[0137] y is a number between 2 and 500, preferably between 3 and 250 or between 2 and 100, and even more preferably between 2 and 70; and

[0138] z is a number between 3 and 500, preferably between 3 and 250 or between 3 and 100, and even more preferably between 3 and 70, and

[0139] Each polymer contains between 0.5 wt% and 15.0 wt% Si-H functional groups, preferably each polymer contains between 1.0 wt% and 12.5 wt% Si-H functional groups, and even more preferably each polymer contains between 1.5 wt% and 10.0 wt% Si-H functional groups.

[0140] Component XL may have a dynamic viscosity of 40 to 1000 mPa.s at 25° C., preferably 50 to 750 mPa.s at 25° C., more preferably 60 to 500 mPa.s at 25° C. If the viscosity of component XL is lower than 40 mPa.s at 25° C., the cohesive force of the cured PSA is too strong to be easily torn apart, and the strong cohesive force results in weak adhesion to the substrate, so that the cured PSA layer leaves fragments of residue on the skin when peeled off.

[0141] Component XL may have a Si—H content of 0.5 to 15 wt%, preferably 1.0 to 12.5 wt%, more preferably 1.5 to 10.0 wt%, based on the total weight of component XL.

[0142] Preferably, the organopolysiloxane crosslinking agent XL may be trimethylsiloxy-terminated polymethylhydrogensiloxane or dimethylhydrogen-terminated polymethylhydrogensiloxane.

[0143] The contents of the organopolysiloxanes A, CE and XL in the composition according to the invention are selected according to the following two molar ratios:

[0144] - the ratio RHAlk = tH / tAlk, and

[0145] - Ratio nH XL / nH CE ;

[0146] in:

[0147] -tH = the number of moles of hydrogen atoms directly bonded to the silicon atoms of the organopolysiloxanes CE and XL;

[0148] -tAlk=the number of moles of alkenyl groups directly bonded to the silicon atoms of the organopolysiloxane A;

[0149] -nH XL = the number of moles of hydrogen atoms directly bonded to the silicon atoms of the organopolysiloxane XL;

[0150] -nH CE = the number of moles of hydrogen atoms directly bonded to the silicon atoms of the organopolysiloxane CE.

[0151] According to the invention, the molar ratio RHAlk is from 2 to 5, preferably from 2.5 to 4. According to the invention, the ratio nH XL / nH CE Below 0.10, preferably 0 to 0.08, more preferably 0 to 0.05. According to a preferred embodiment, the composition according to the invention is free or substantially free of organohydrogensiloxane crosslinker XL.

[0152] As the hydrosilylation catalyst D that can be used according to the present invention, the compound of the metal belonging to the platinum group known to those skilled in the art can be mentioned. The metal of the platinum group is those called platinum metals (platinoids), and the platinum metal is a term that combines ruthenium, rhodium, palladium, osmium and iridium in addition to platinum. Preferably, a compound of platinum and rhodium is used. The complex of platinum and organic products described in patents US 3,159,601, US 3,159,602 and US 3,220,972 and European patents EP 0 057 459, EP 0 188978 and EP 0 190 530, and the complex of platinum and vinyl organosiloxane described in patent US 3,419,593 can be used in particular. The catalyst that is usually preferred is platinum. As examples, platinum black, chloroplatinic acid, chloroplatinic acid modified with alcohol, complex of chloroplatinic acid with olefins, aldehydes, vinyl siloxanes or acetylenic alcohols can be mentioned in particular. Karstedt's solution or complex as described in US Pat. No. 3,775,452, chloroplatinic acid hexahydrate or a platinum catalyst containing a carbene ligand are preferred.

[0153] Preferably, component D is a solution of a platinum complex in a vinyl terminated polydimethylsiloxane.

[0154] According to one embodiment of the present invention, solvent E is selected from: aliphatic C6-C 16 Hydrocarbons, polydimethylsiloxanes with a viscosity of 0.65 to 5 mPa.s at 25°C containing trimethylsilyl end groups, cyclopolydimethylsiloxanes, (3-octyl)heptamethyltrisiloxane, toluene, xylene, C1-C8 alkyl esters, C2-C4 carboxylic acids and mixtures thereof.

[0155] In particular, solvent E is at least one solvent. Solvent E is at least one medically approved solvent. For example, it is selected from toluene, xylene, heptane, ethyl acetate, more preferably ethyl acetate for healthcare applications.

[0156] The amount of the solvent E is 20% by weight to 70% by weight, preferably 30% by weight to 60% by weight, based on the total weight of the composition.

[0157] Hydrosilylation inhibitors F may be used in the compositions of the present invention.

[0158] As hydrosilylation inhibitors useful according to the invention, mention may be made of those selected from the group consisting of α-acetylenic alcohols, α,α'-acetylenic diesters, conjugated ene-yne ​​compounds, α-acetylenic ketones, acrylonitrile, maleates, fumarates, and mixtures thereof. These compounds capable of acting as hydrosilylation inhibitors are well known to those skilled in the art. They may be used alone or as a mixture.

[0159] The inhibitor of the α-acetylenic alcohol type may be selected from the compounds of the following formula (F1):

[0160] (R 8 )(R 9 )C(OH)-C≡CH (F1)

[0161] in:

[0162] - Group R 8 represents an alkyl group, a cycloalkyl group, a (cycloalkyl)alkyl group, a C6-C 10 Aryl group or C7-C 18 Arylalkyl groups,

[0163] - Group R 9 represents a hydrogen atom, an alkyl group, a cycloalkyl group, a (cycloalkyl)alkyl group, a C6-C 10 Aryl group or C7-C 18 Arylalkyl groups,

[0164] - or R 8 and R 9 Together with the carbon atoms to which they are attached they form a 5-, 6-, 7- or 8-membered aliphatic ring, optionally substituted one or more times.

[0165] According to formula (F1):

[0166] - The term "alkyl" refers to a saturated hydrocarbon chain containing 1 to 20 carbon atoms, preferably 1 to 8 carbon atoms. The alkyl group may be selected from methyl, ethyl, isopropyl, n-propyl, tert-butyl, isobutyl, n-butyl, n-pentyl, isopentyl and 1,1-dimethylpropyl;

[0167] - The term "cycloalkyl" according to the present invention refers to a monocyclic or polycyclic, preferably monocyclic or bicyclic, saturated hydrocarbon radical containing 3 to 20 carbon atoms, preferably 5 to 8 carbon atoms. When the cycloalkyl radical is polycyclic, the multiple cyclic cores may be linked to each other by covalent bonds and / or by spin atoms, and / or fused to each other. The cycloalkyl radical may be selected from cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, adamantane and norbornane;

[0168] - the term "(cycloalkyl)alkyl" according to the invention refers to a cycloalkyl group, also as defined above, attached to an alkyl group, also as defined above;

[0169] - "Aryl" according to the present invention refers to a monocyclic or polycyclic aromatic hydrocarbon group containing 6 to 10 carbon atoms. The aryl group may be selected from phenyl, naphthyl and anthracenyl;

[0170] - The term "arylalkyl" according to the present invention refers to an aryl group, also as defined above, attached to an alkyl group, also as defined above.

[0171] According to a preferred embodiment, in formula (F1), R 8 and R 9 Together with the carbon atoms to which they are attached, they form an unsubstituted 5-, 6-, 7- or 8-membered aliphatic ring. 8 and R 9 The same or different, independently of each other, represent a single valence C1-C 12 , preferably a C1-C6 alkyl group.

[0172] The inhibitor of α-acetylenic alcohols which can be used according to the invention can be selected from the following compounds: 1-ethynyl-1-cyclopentanol; 1-ethynyl-1-cyclohexanol (also known as ECH); 1-ethynyl-1-cycloheptanol; 1-ethynyl-1-cyclooctanol; 3-methyl-1-butyn-3-ol (also known as MBT); 3-methyl-1-pentyn-3-ol; 3-methyl-1-hexyn-3-ol; 3-methyl-1-heptyn-3-ol; 3-methyl-1-octyn-3-ol; 3-methyl-1-nonyn-3-ol; 3-methyl-1-decyn-3-ol; 3-methyl-1-dodecyn-3-ol; 3-methyl-1-pentadecin-3-ol; 3-ethyl-1-pentyn-3-ol; 3-ethyl -1-hexyn-3-ol; 3-ethyl-1-heptyn-3-ol; 3,5-dimethyl-1-hexyn-3-ol; 3-isobutyl-5-methyl-1-hexyn-3-ol; 3,4,4-trimethyl-1-pentyn-3-ol; 3-ethyl-5-methyl-1-heptyn-3-ol; 3,6-diethyl-1-nonyn-3-ol; 3,7,11-trimethyl-1-dodecyn-3-ol (also known as TMDDO); 1,1-diphenyl-2-propyn-1-ol; 3-butyn-2-ol; 1-pentyn-3-ol; 1-hexyn-3-ol; 1-heptyn-3-ol; 5-methyl-1-hexyn-3-ol; 4-ethyl-1-octyn-3-ol and 9-ethynyl-9-fluorenol.

[0173] The inhibitor of the α,α'-acetylenic diester type may be selected from the compounds of the following formula (F2):

[0174]

[0175] The group R 10 and R 11 are the same or different and independently represent an alkyl group, a cycloalkyl group, a (cycloalkyl)alkyl group, a C6-C 10 Aryl group, C7-C 18 an arylalkyl group or a silyl group.

[0176] The term "silyl" according to the present invention refers to a group of formula -SiR3, wherein each symbol R independently represents an alkyl group containing 1 to 20 carbon atoms, preferably 1 to 8 carbon atoms. The silyl group may for example be a trimethylsilyl group.

[0177] According to a particular embodiment, in formula (F2), R 10 and R 11 The same or different, independently represent C1-C 12 , preferably a C1-C6 alkyl group, or a trimethylsilyl group. The inhibitor of α,α'-acetylenic diesters that can be used according to the present invention can be selected from the following compounds: acetylene-dicarboxylic acid dimethyl ester (DMAD), acetylene-dicarboxylic acid diethyl ester, acetylene-dicarboxylic acid tert-butyl ester and acetylene-dicarboxylic acid bis(trimethylsilyl) ester.

[0178] The inhibitor of the conjugated ene-yne ​​compound type may be selected from the compounds of the following formula (F3):

[0179]

[0180] in:

[0181] - Group R 12 , R 13 and R 14 independently of one another represent a hydrogen atom, an alkyl group, a cycloalkyl group, a (cycloalkyl)alkyl group, a C6-C 10 Aryl group or C7-C 18 Arylalkyl groups,

[0182] - or from the group R 12 , R 13 and R 14 At least two of the groups together with the carbon atoms to which they are attached form a 5-, 6-, 7- or 8-membered aliphatic ring, optionally substituted one or more times

[0183] According to a particular embodiment, the group R 12 , R 13 and R 14 represent hydrogen atoms independently of each other, C1-C 12 , preferably a C1-C6 alkyl group, or a C6-C 10 Aryl groups. Inhibitors of conjugated ene-yne ​​compounds that can be used according to the invention can be selected from the following compounds: 3-methyl-3-pentene-1-yne; 3-methyl-3-hexene-1-yne; 2,5-dimethyl-3-hexene-1-yne; 3-ethyl-3-butene-1-yne; and 3-phenyl-3-butene-1-yne. According to another specific embodiment, selected from the group R 12 , R13 and R 14 The two groups together with the carbon atoms to which they are attached form an unsubstituted 5-, 6-, 7- or 8-membered aliphatic ring and the remaining third group represents a hydrogen atom or a C1-C 12 , preferably C1-C6 alkyl groups. An inhibitor of the conjugated ene-yne ​​compound that can be used according to the invention can be 1-ethynyl-1-cyclohexene.

[0184] The α-acetylenic ketone type inhibitor may be selected from compounds of the following formula (F4):

[0185]

[0186] Where R 15 represents an alkyl group, a cycloalkyl group, a (cycloalkyl)alkyl group, a C6-C 10 Aryl group or C7-C 18 The arylalkyl group, the alkyl group, the cycloalkyl group, the (cycloalkyl)alkyl group, the aryl group or the arylalkyl group may be optionally substituted one or more times by chlorine, bromine or iodine atoms.

[0187] According to a preferred embodiment, R 15 Indicates one price C1-C 12 , preferably C1-C6 alkyl groups, optionally substituted one or more times by chlorine or bromine atoms, or cycloalkyl groups, or C6-C 10 Aryl groups. Inhibitors of α-acetylenic ketones that can be used according to the invention can be selected from the following compounds: 1-octyne-3-one, 8-chloro-1-octyne-3-one; 8-bromo-1-octyne-3-one; 4,4-dimethyl-1-octyne-3-one; 7-chloro-1-heptyne-3-one; 1-hexyne-3-one; 1-pentyne-3-one; 4-methyl-1-pentyne-3-one; 4,4-dimethyl-1-pentyne-3-one; 1-cyclohexyl-1-propyne-3-one; benzoacetylene and o-chlorobenzoylacetylene.

[0188] The acrylonitrile type inhibitor may be selected from compounds of the following formula (F5):

[0189]

[0190] Where R 16 and R 17 represents independently of one another a hydrogen atom, a chlorine, a bromine or an iodine atom, an alkyl group, a cycloalkyl group, a (cycloalkyl)alkyl group, a C6-C 10 Aryl group or C7-C 18 The arylalkyl group, the alkyl group, the cycloalkyl group, the (cycloalkyl)alkyl group, the aryl group or the arylalkyl group may be optionally substituted one or more times by chlorine, bromine or iodine atoms.

[0191] The inhibitor of acrylonitrile which can be used according to the invention may be selected from the following compounds: acrylonitrile; methacrylonitrile; 2-chloroacrylonitrile; crotononitrile and cinnamonitrile.

[0192] The maleate or fumarate type inhibitor may be selected from compounds of the following formulae (F6) and (F7):

[0193]

[0194] Where R 18 and R 19 are the same or different and independently represent an alkyl or alkenyl group, a cycloalkyl group, a (cycloalkyl)alkyl group, a C6-C 10 Aryl group or C7-C 18 Arylalkyl groups, the alkyl, alkenyl, cycloalkyl, (cycloalkyl)alkyl, aryl and arylalkyl groups may be substituted with alkoxy groups.

[0195] According to the present invention, the term "alkenyl" refers to a saturated hydrocarbon chain containing 2 to 6 carbon atoms and containing at least one double unsaturation. Preferably, the alkenyl group is selected from vinyl or allyl. According to formula (F6) or (F7), the term "alkoxy" refers to an alkyl group as defined above bonded to an oxygen atom. The alkoxy group may be selected from methoxy, ethoxy, propoxy and butoxy.

[0196] According to a particular embodiment, R 18 and R 19 The same or different, independently represent C1-C 12 , preferably a C1-C6 alkyl or alkenyl group, optionally substituted by a C1-C6 alkoxy group.

[0197] As maleate or fumarate inhibitors which can be used according to the invention, one may choose among diethyl fumarate, diethyl maleate, diallyl fumarate, diallyl maleate and bis(methoxyisopropyl) maleate.

[0198] These inhibitors are added in an amount of 1 ppm to 50,000 ppm by weight, in particular 10 ppm to 10,000 ppm, preferably 20 ppm to 2000 ppm, even more preferably 800 ppm to 2000 ppm, relative to the weight of the total silicone composition.

[0199] The medical silicone pressure-sensitive adhesive composition according to the present invention can be applied to various substrates suitable for medical applications. Depending on the application field, the substrate can be a carrier of very different properties.

[0200] According to a preferred embodiment, the substrate is a woven, nonwoven or knitted textile, or a film of plastic material. The term "nonwoven" refers to any structure consisting of textile materials such as fibers, continuous filaments or cut yarns (regardless of their nature or origin), which are formed into a web by any means and connected by any means, excluding the interweaving of yarns. Nonwoven textiles are products such as those described below: the product has the appearance of a porous textile consisting mainly of fibers and is produced by a method other than spinning, weaving, knitting or knotting.

[0201] According to another preferred embodiment, the substrate is made of a plastic material. A wide variety of plastic materials are suitable for use as the substrate according to the present invention. Examples include: polyvinyl chloride, polypropylene, regenerated cellulose, polyethylene terephthalate (PET) and polyurethane, in particular blown melt polyurethane. The substrate can be a perforated flexible polyurethane film or a continuous flexible polyurethane film. Such a flexible polyurethane film can be produced by blowing melt polyurethane. When the substrate is a flexible polyurethane film, the thickness is typically 5 μm to 600 μm, preferably 5 μm to 250 μm and more preferably 10 μm to 100 μm.

[0202] Alternatively, the substrate may be selected from paper, nonwoven fabrics, and elastic fabrics.

[0203] According to a preferred embodiment, the substrate may be selected from paper, nonwoven fabrics, elastic fabrics or plastic films, preferably films of plastics selected from polyvinyl chloride, polypropylene, regenerated cellulose, polyethylene terephthalate (PET) and polyurethane.

[0204] Those skilled in the art can adjust the medical organosilicon pressure-sensitive adhesive composition according to the final application. Generally, the medical organosilicon pressure-sensitive adhesive composition according to the present invention may have a dynamic viscosity of 500 to 5000 mPa.s, preferably 800 to 3000 mPa.s, more preferably 1000 to 2500 mPa.s at 25°C.

[0205] The medical organosilicon pressure-sensitive adhesive composition according to the present invention can be applied to or coated on various substrates by any technique known to those skilled in the art. As a technique for depositing the medical organosilicon pressure-sensitive adhesive composition according to the present invention, it can be mentioned that, for example, a coating technique is implemented in the following manner: using a scraper, especially a roller-lined scraper, an air floating knife and a belt-lined scraper, or by padding, that is, by extrusion between two rollers, or by a licking roller, a rotating machine, a reverse roller or transfer, or spraying. As other coating techniques, curtain coating techniques can be mentioned. Curtain coating is a method of applying a coating liquid to an article or a carrier. Curtain coating is characterized in that a curtain of coating liquid falling from the lip of a hopper is formed to fall freely, and under the action of gravity, it encounters an article moving through the curtain to form a coating (or coating layer). This technology has been widely used in the field of preparing multilayer photosensitive silver carriers (see, for example, patents US3,508,947, US 3,508,947 or EP 537086).

[0206] Then, the medical silicone pressure-sensitive adhesive composition coated on the substrate is crosslinked, for example, at a temperature of 100°C to 160°C, preferably 120°C to 150°C.

[0207] Therefore, the substrate coated with the silicone pressure-sensitive adhesive G is obtained by crosslinking the silicone pressure-sensitive adhesive composition according to the present invention. DETAILED DESCRIPTION

[0208] Other advantages and features of the invention will emerge on reading the following examples, which are given by way of illustration and are in no way limiting. Example

[0209] Probe stickiness test (Probe Tack test): This adhesion test was conducted by cutting the cured PSA laminate into 2.5 cm (length) × 2.5 cm (width) strips, removing the release liner from the PSA layer, and conducting the adhesion test on a PT1000 Probe Tack Tester from Cheminstrument Co. Ltd according to ASTM D2979. The atmospheric conditions were 23°C and 50% RH.

[0210] Peel Adhesion: The peel adhesion test was conducted by cutting the cured PSA laminate into strips of 10 cm (length) × 2.5 cm (width), removing the release liner from the PSA layer, adhering the PSA layer to a cardboard of 15 cm × 5 cm size, and laminating them with a 2 kg rubber roller for two cycles. Then, the peel test was conducted on a tester PA1000-180 Peel Tester of Cheminstrument Co. Ltd according to FINAT FTM1. The atmospheric conditions were 23°C & 50% RH.

[0211] The raw materials used in the examples are listed below:

[0212] Organopolysiloxane A: Vinyl-terminated polydimethylsiloxane M Vi D x M Vi , Mw = 560,000 g / mol, vinyl content = 0.015% by weight, consistency = 800 mm / 10

[0213] Organopolysiloxane resin B: M x Q y Q (OH) z Resin, Mw=5,500 g / mol, x / (y+z)=0.9, OH=1.0% by weight

[0214] Chain Extender CE: Hydrogen-terminated polydimethylsiloxane oil M H D y M H , viscosity = 8.0 mPa.s, Si-H content = 5.51% by weight

[0215] Catalyst D: Pt content = 0.2% by weight, dissolved in 350 mPa.s vinyl-terminated polydimethylsiloxane

[0216] Solvent E: Ethyl acetate Examples 1-5

[0217] All components were uniformly mixed in the amounts shown in the table below.

[0218] The obtained composition was coated on a PET film (60-90 g / m 2 ) and then placed in an oven at 120°C for 30 minutes.

[0219] Table 1

[0220] The composition according to the invention (Example 3) provides an adhesive with very good properties after curing, which can be advantageously used as a medical PSA. Below the claimed molar ratio RHAlk (Example 1 and Example 2), the composition does not show a cohesive network. Above the claimed molar ratio RHAlk (Example 4 and Example 5), the cured composition loses its release properties and appears closer to an elastomer.

Claims

1. A medical silicone pressure-sensitive adhesive composition, comprising: at least one organopolysiloxane A comprising, per molecule, at least two C2-C6 alkenyl groups each bonded to a silicon atom, wherein the organopolysiloxane A is an organopolysiloxane gum, - at least one organopolysiloxane resin B comprising one or more OH groups bonded to silicon atoms, - at least one organopolysiloxane chain extender CE having exactly two terminal hydrogen atoms bonded to silicon atoms, - optionally, at least one organopolysiloxane crosslinker XL having at least three hydrogen atoms bonded to silicon atoms, - at least one hydrosilylation catalyst D, - at least one solvent E, and - optionally, at least one hydrosilylation inhibitor F, wherein the organopolysiloxanes A, CE and XL are selected so that the molar ratio RHAlk=tH / tAlk is 2 to 5; and nH XL / nH CE Ratio is less than 0.10, where: -tH = the number of moles of hydrogen atoms directly bonded to the silicon atoms of the organopolysiloxanes CE and XL; -tAlk=the number of moles of alkenyl groups directly bonded to the silicon atoms of the organopolysiloxane A; -nH XL = the number of moles of hydrogen atoms directly bonded to the silicon atoms of the organopolysiloxane XL; -nH CE = the number of moles of hydrogen atoms directly bonded to the silicon atoms of the organopolysiloxane CE. 2 . The medical organosilicon pressure-sensitive adhesive composition according to claim 1 , wherein the molar ratio RHAlk is 2.5 to 4.

3. The medical organosilicon pressure-sensitive adhesive composition according to claim 1 or claim 2, wherein nH XL / nH CE The ratio is strictly lower than 0.10, preferably between 0 and 0.08, more preferably between 0 and 0.

05.

4. The medical organosilicon pressure-sensitive adhesive composition according to any one of claims 1 to 3, wherein the composition is free of or substantially free of an organohydrogensiloxane crosslinker XL.

5. The medical organosilicon pressure-sensitive adhesive composition according to any one of claims 1 to 4, wherein the organopolysiloxane A is selected from dimethylvinyl-terminated polydimethylsiloxane, dimethylvinyl-terminated polydimethylmethylvinylsiloxane, trimethyl-terminated polydimethylmethylvinylsiloxane, and more preferably selected from dimethylvinyl-terminated polydimethylsiloxane.

6. The medical organosilicone pressure-sensitive adhesive composition according to any one of claims 1 to 5, wherein the organopolysiloxane A is an organopolysiloxane gum having a consistency of 200 to 2000 mm / 10, preferably 300 to 1800 mm / 10, more preferably 500 to 1500 mm / 10 at 25°C.

7. The medical organosilicone pressure-sensitive adhesive composition according to any one of claims 1 to 6, wherein the organopolysiloxane A is used in an amount of 15 to 45 wt%, preferably 20 to 40 wt%, based on the total amount of components A+B+XL+CE.

8. The medical organosilicon pressure-sensitive adhesive composition according to any one of claims 1 to 7, wherein the organopolysiloxane resin B containing hydroxyl groups is selected from: a) MQ (OH) A hydroxylated silicone resin comprising siloxy units M and Q of the formula (OH) Copolymers: - M=R 3 R 4 R 5 SiO 1 / 2 ,and - Q (OH) =(OH)SiO 3 / 2 , Wherein siloxy units Q=SiO are optionally present 4 / 2 ; b) MD Vi Q (OH) A hydroxylated silicone resin comprising siloxy units M, D Vi and Q (OH) Copolymers: - M=R 3 R 4 R 5 SiO 1 / 2 , -D Vi =(Vi)(R 3 )SiO 2 / 2 ,and - Q (OH) =(OH)SiO 3 / 2 , Wherein siloxy units Q=SiO are optionally present 4 / 2 ; c) MM Vi Q (OH) A hydroxylated silicone resin comprising siloxy units M, M Vi and Q (OH) Copolymers: - M=R 3 R 4 R 5 SiO 1 / 2 , -M Vi =(Vi)(R 3 )(R 4 )SiO 2 / 2 ,and - Q (OH) =(OH)SiO 3 / 2 , Wherein siloxy units Q=SiO are optionally present 4 / 2 ; d) MDT (OH) T-type hydroxylated silicone resin, which comprises siloxy units M, D, T (OH) Copolymers with T: - M=R 3 R 4 R 5 SiO 1 / 2 , - D=R 3 R 4 SiO 2 / 2 , - T (OH) =(OH)R 3 SiO 2 / 2 , - T=R 3 SiO 3 / 2 ,as well as e) DT (OH) T-type hydroxylated silicone resin, which comprises siloxy units D, T (OH) Copolymers with T: - D=R 3 R 4 SiO 2 / 2 , - T (OH) =(OH)R 3 SiO 2 / 2 , - T=R 3 SiO 3 / 2 ,and In the formula, the symbol Vi = vinyl group, and the symbol R 3 , R 4 and R 5 Independently selected from: - has a linear or branched alkyl group containing 1 to 8 carbon atoms and optionally substituted by one or more halogen atoms, and is preferably selected from methyl, ethyl, isopropyl, tert-butyl and n-hexyl, and - an aryl or alkylaryl group having 6 to 14 carbon atoms, inclusive, and preferably selected from phenyl, xylyl and tolyl.

9. The medical organosilicone pressure-sensitive adhesive composition according to any one of claims 1 to 8, wherein the organopolysiloxane resin B is used in an amount of 25 to 80 wt%, preferably 40 to 60 wt%, based on the total amount of components A+B+XL+CE.

10. The medical organosilicon pressure-sensitive adhesive composition according to any one of claims 1 to 9, wherein the organopolysiloxane CE has a formula M H D x M H ,in: -M H =Siloxy unit of the formula: (H)(CH3)2SiO 1 / 2 - D = siloxy unit of the formula: (CH3)2SiO 2 / 2 ,and -x is an integer of 1-200, preferably 1-150, even more preferably 3-120.

11. The medical silicone pressure-sensitive adhesive composition according to any one of claims 1 to 10, wherein the solvent E is selected from: aliphatic C6-C 16 Hydrocarbons, polydimethylsiloxanes with a viscosity of 0.65 to 5 mPa.s at 25°C containing trimethylsilyl end groups, cyclic polydimethylsiloxanes, (3-octyl)heptamethyltrisiloxane, toluene, xylene, C1-C8 alkyl esters, C2-C4 carboxylic acids and mixtures thereof, preferably selected from toluene, xylene, heptane and ethyl acetate, more preferably, solvent E is ethyl acetate for healthcare applications.

12. The medical organosilicon pressure-sensitive adhesive composition according to any one of claims 1 to 11, wherein the amount of the solvent E is 20 to 70% by weight, preferably 30 to 60% by weight, based on the total weight of the composition.

13. A method of making a skin adhesive article comprising the steps of: The medical organosilicon pressure-sensitive adhesive composition according to any one of claims 1 to 12 is continuously or discontinuously coated on at least one of the two surfaces of the substrate, and the medical organosilicon pressure-sensitive adhesive composition is crosslinked to form an organosilicon pressure-sensitive adhesive G.

14. The method according to claim 13, wherein the substrate is selected from paper, nonwoven fabric, elastic fabric or plastic film, preferably, a film of plastic selected from polyvinyl chloride, polypropylene, regenerated cellulose, polyethylene terephthalate (PET) and polyurethane.

15. A skin adhesive article comprising a substrate coated continuously or discontinuously on at least one of its two surfaces with a silicone pressure-sensitive adhesive G obtained by crosslinking the medical silicone pressure-sensitive adhesive composition according to any one of claims 1 to 12.

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