Medical silicone pressure sensitive adhesive composition

Abstract

The present invention relates to a medical silicone pressure sensitive adhesive composition comprising: an organopolysiloxane A, an organopolysiloxane resin B, an organopolysiloxane crosslinker XL, an organopolysiloxane chain extender CE, a hydrosilylation catalyst D, a solvent E and a hydrosilylation inhibitor F, wherein the organopolysiloxanes A, CE and XL are chosen so that the molar ratio RHAlk = tH / tAlk is between 3.5 and 8; and nH XL / nH CE is between 0.13 and 11, wherein: - tH = the number of moles of hydrogen atoms directly bonded to silicon atoms of the organopolysiloxanes XL and CE; - tAlk = the number of moles of alkenyl groups directly bonded to silicon atoms of the organopolysiloxane A; - nH XL = the number of moles of hydrogen atoms directly bonded to silicon atoms of the organopolysiloxane XL; - nH CE = the number of moles of hydrogen atoms directly bonded to silicon atoms of the organopolysiloxane CE. The present invention also relates to a process for coating a substrate by using this medical silicone pressure sensitive adhesive composition, to a coated substrate obtainable according to this process, and also to a skin-adhesive article by using this medical silicone pressure sensitive adhesive composition.

Description

Technical Field

[0001] The present invention relates to the field of medical pressure-sensitive adhesives (PSAs). In particular, the present invention relates to medical silicone pressure-sensitive adhesive compositions, methods for coating a substrate using the medical silicone pressure-sensitive adhesive composition, coated substrates obtainable by the method, and skin-adhesive articles using the medical silicone pressure-sensitive adhesive composition. Background Technology

[0002] PSA is an abbreviation for "pressure-sensitive adhesive," a term well-known in the field and widely used in various applications, particularly in medical applications. Currently, most skin contact products on the medical market, such as tapes, patches, and bandages, are made from acrylic-based PSA. However, acrylic-based PSA has some drawbacks, such as poor sweat (water) resistance, poor biocompatibility, and a high sensitization rate on human skin, especially in infants and children.

[0003] Silicone-based PSAs are also widely used in medical applications for contact with or against the skin. Silicone-based PSAs can easily adhere to surfaces through contact or under light pressure. They offer significant advantages over acrylic-based PSAs. Silicone-based PSAs exhibit 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 novel medical applications due to their biocompatibility and permeability, which allows for the diffusion of oxygen, carbon dioxide, and water vapor, making them ideal for medical applications requiring enhanced ventilation.

[0004] WO2017158249A1 describes a silicone gel that can be used as a skin adhesive. This silicone gel exhibits good adhesion to polyester or polyurethane substrates and better adhesion to skin than prior art gels. Due to its inherent properties, this silicone gel lacks adhesion to moist skin, which is advantageous for wound care applications as it avoids secondary damage to the wound when applying dressings. However, for non-traumatic medical materials that adhere to the skin, moist environments or sweating often cause the gel to lose its adhesiveness and then detach.

[0005] KR101731612B1 describes a medical silicone pressure-sensitive adhesive composition based on vinyl silicone resin. Compared with conventional acrylate pressure-sensitive adhesives, this composition is harmless to human skin, exhibits excellent adhesion, including initial adhesion and re-adhesion, and also demonstrates excellent absorbency and wound healing effects. However, this document does not investigate medical silicone pressure-sensitive adhesives based on hydroxyl silicone resins, nor does it consider the influence of high molecular weight terminal vinyl polysiloxanes. Furthermore, factors such as XL viscosity, tH / tAlk ratio, and nH... XL / nH CE The effects of factors such as ratio on the application performance of medical silicone pressure-sensitive adhesives have not been systematically studied and clearly defined. The residue left on the skin after application of this pressure-sensitive adhesive has not been evaluated.

[0006] WO2020099999A1 describes a medical silicone pressure-sensitive adhesive that exhibits enhanced adhesion while minimizing skin damage and pain during adhesive removal. In this document, the condensation product is formed through a reaction between a polysiloxane containing terminal hydroxyl groups and a silicate resin, followed by the mixing of a non-reactive polysiloxane. In the subsequent tape production process, an electron beam is used to promote the crosslinking of the non-reactive polysiloxane, thereby forming a pressure-sensitive adhesive layer on the substrate. In this document, the PSA production process is complex, and the control of the condensation reaction conditions significantly impacts product quality. The subsequent curing process requires an electron beam, and the equipment is relatively expensive. Furthermore, the properties of the condensation-type PSA have been determined by the preceding condensation reaction, which limits subsequent applications.

[0007] Therefore, there is always a need to obtain a silicone-based pressure-sensitive adhesive composition with excellent overall performance suitable for medical applications. Summary of the Invention

[0008] This invention has solved the problems of the prior art.

[0009] In particular, the present invention aims to provide a medical silicone pressure-sensitive adhesive composition that, in addition to retaining the inherent properties of silicone-based PSA such as air permeability, water resistance, low irritation and biocompatibility, also has adhesive properties comparable to acrylic-based PSA. Therefore, it can increasingly replace acrylic-based PSA in the medical field and discover some new applications where acrylic-based PSA is not suitable.

[0010] The silicone-based pressure-sensitive adhesive composition according to the present invention provides excellent overall properties suitable for medical applications after crosslinking, such as the following excellent overall properties: easy to tear, no visible residue on the skin, good anchoring on the substrate, good peel adhesion, good tack, suitable peel force and acceptable re-attachment performance.

[0011] The silicone-based pressure-sensitive adhesive (PSA) composition according to the invention provides a silicone-based pressure-sensitive adhesive (PSA) after crosslinking, which has good anchoring properties on substrates such as those made of paper, PU (polyurethane), TPU (thermoplastic polyurethane), nonwoven fabrics and elastic fabrics; good adhesion (or "stickiness") to the skin, while avoiding discomfort when such PSA is separated from the skin.

[0012] Therefore, the present invention relates to a medical silicone pressure-sensitive adhesive composition, the composition comprising:

[0013] - At least one organopolysiloxane A, each molecule of which contains at least two C2-C6 alkenyl groups, each bonded to a silicon atom.

[0014] - At least one organopolysiloxane resin B, which contains OH groups bonded to silicon atoms.

[0015] - At least one organopolysiloxane crosslinking agent XL, having at least three hydrogen atoms bonded to silicon atoms,

[0016] - At least one organopolysiloxane chain extender CE having exactly two terminal hydrogen atoms bonded to silicon atoms,

[0017] -At least one hydrogenation silylation catalyst D,

[0018] -At least one solvent E,

[0019] -At least one hydrosilylation inhibitor F,

[0020] Among them, organopolysiloxanes A, CE, and XL were selected such that the molar ratio RHAlk = tH / tAlk was 3.5 to 8; and nH XL / nH CE It ranges from 0.13 to 11, where:

[0021] -tH = the number of hydrogen atoms directly bonded to the silicon atoms of organopolysiloxanes XL and CE;

[0022] -tAlk = the number of alkenyl groups that are directly bonded to the silicon atoms of organopolysiloxane A;

[0023] -nH XL = The number of hydrogen atoms directly bonded to the silicon atoms of organopolysiloxane XL;

[0024] -nH CE = The number of moles of hydrogen atoms that are directly bonded to the silicon atoms of the organopolysiloxane CE.

[0025] The medical silicone pressure-sensitive adhesive composition according to the present invention is a precursor of silicone pressure-sensitive adhesive G and can be crosslinked by hydrosilylation.

[0026] Another object of the present invention is to provide a skin-adhesive article comprising a substrate on at least one of its two surfaces continuously or discontinuously coated with a silicone pressure-sensitive adhesive obtained by crosslinking a medical silicone pressure-sensitive adhesive composition, the medical silicone pressure-sensitive adhesive composition comprising:

[0027] - At least one organopolysiloxane A, each molecule of which contains at least two C2-C6 alkenyl groups, each bonded to a silicon atom.

[0028] - At least one organopolysiloxane resin B, which contains OH groups bonded to silicon atoms.

[0029] - At least one organopolysiloxane crosslinking agent XL, having at least three hydrogen atoms bonded to silicon atoms,

[0030] - At least one organopolysiloxane chain extender CE having exactly two terminal hydrogen atoms bonded to silicon atoms,

[0031] -At least one hydrogenation silylation catalyst D,

[0032] -At least one solvent E,

[0033] -At least one hydrosilylation inhibitor F,

[0034] Among them, organopolysiloxanes A, CE, and XL were selected such that the molar ratio RHAlk = tH / tAlk was 3.5 to 8; and nH XL / nH CE It ranges from 0.13 to 11, where:

[0035] -tH = the number of hydrogen atoms directly bonded to the silicon atoms of organopolysiloxanes XL and CE;

[0036] -tAlk = the number of alkenyl groups that are directly bonded to the silicon atoms of organopolysiloxane A;

[0037] -nH XL = The number of hydrogen atoms directly bonded to the silicon atoms of organopolysiloxane XL;

[0038] -nH CE = The number of moles of hydrogen atoms that are directly bonded to the silicon atoms of the organopolysiloxane CE.

[0039] Another object of the present invention is to provide a method for coating a substrate using a medical silicone pressure-sensitive adhesive composition according to the present invention.

[0040] Another object of the present invention is to provide a coated substrate that can be obtained by the method according to the present invention.

[0041] Another object of the present invention is to provide a substrate coated with an organosilicon pressure-sensitive adhesive G obtained by crosslinking an organosilicon pressure-sensitive adhesive composition according to the present invention.

[0042] The inventors of this invention have employed considerable research methods and conducted numerous experiments to achieve these objectives. The inventors have discovered that by selecting organopolysiloxanes A, CE, and XL such that the molar ratio RHAlk = tH / tAlk is 3.5 to 8; and nH XL / nH CE The ratio is from 0.13 to 11, thereby obtaining a medical silicone pressure-sensitive adhesive composition that, after crosslinking, provides excellent overall properties suitable for medical applications, such as the following excellent overall properties: easy tearing, no visible residue on the skin, good anchoring on substrates, good peel adhesion, good tack, suitable peel force, and acceptable re-attachment properties.

[0043] The inventors of this invention have also discovered that by selecting components CE and XL such that the ratio nH XL / nH CE Within a specific range depending on the end use, this medical silicone pressure-sensitive adhesive composition can be specifically applied to a variety of specific substrates, particularly those made of paper, TPU, nonwoven fabrics, and elastic fabrics, thereby producing good performance in the final application of PSA.

[0044] Component A - Organopolysiloxane A

[0045] Component A may be at least two C2-C6 alkenyl-substituted organosilicon polymers, used as the backbone in the composition.

[0046] According to one embodiment, organopolysiloxane A is an organopolysiloxane adhesive with a consistency of 200 mm / 10 to 2000 mm / 10, preferably 300 mm / 10 to 1800 mm / 10, and more preferably 500 mm / 10 to 1500 mm / 10 at 25°C.

[0047] According to one embodiment, organopolysiloxane A is an organopolysiloxane adhesive with 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 600,000 g / mol to 900,000 g / mol. This weight-average molecular weight (Mw) is determined by gel permeation chromatography using polystyrene as a standard.

[0048] According to one embodiment, organopolysiloxane A is an organopolysiloxane adhesive having a viscosity of greater than 600,000 mPa·s at 25°C, preferably greater than 1,000,000 mPa·s at 25°C.

[0049] According to another embodiment, the medical silicone pressure-sensitive adhesive composition according to the present invention comprises at least two organopolysiloxanes A, wherein the first organopolysiloxane A' is an adhesive as defined above, and the second organopolysiloxane A" is an oil having a dynamic viscosity of 10-500,000 mPa·s at 25°C, preferably 100-100,000 mPa·s at 25°C, more preferably 10,000-100,000 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".

[0050] All viscosities considered in this specification correspond to “Newtonian” dynamic viscosity at 25°C, i.e., dynamic viscosity measured in a manner known per se using a Brookfield viscometer at a sufficiently low shear rate gradient that makes the measured viscosity independent of the velocity gradient.

[0051] The consistency or penetrability of the adhesive was determined at 25°C using a PNR12 translucency meter or an equivalent model that allows the cylindrical head to be applied to the sample under standardized conditions. The penetration of the adhesive is defined as the depth, expressed in tenths of a millimeter, that the calibrated cylinder penetrates the sample in one minute. For this purpose, the adhesive sample was introduced into an aluminum cup with a diameter of 40 mm and a height of 60 mm. The bronze or brass cylindrical head, with a diameter of 6.35 mm and a height of 4.76 mm, was carried by a 51 mm long, 3 mm diameter metal rod compatible with the translucency meter. This rod was weighted with an additional 100 g load. The total weight of the assembly was 151.8 g, of which 4.3 g was from the cylindrical section and its supporting rod. The cup containing the adhesive sample was placed in a constant temperature bath set to 25°C ± 0.5°C for at least 30 minutes. Measurements were performed according to the manufacturer's instructions. The depth (V), expressed in tenths of a millimeter, and the time (t) in seconds to reach this depth were displayed on the machine. The penetration is equal to 60 V / t, expressed as one-tenth of a millimeter per minute.

[0052] Preferably, the at least one organopolysiloxane A may comprise:

[0053] (I) At least two silyloxy units of formula (A1):

[0054] (Y) a (Z) b SiO (4-(a+b)) / 2 (A1)

[0055] in:

[0056] -Y represents a monovalent group containing 2-6 carbon atoms with at least two alkenyl groups;

[0057] -Z indicates a monovalent group containing 1-20 carbon atoms and not an alkenyl group;

[0058] -a and b represent integers, where a is 1, 2 or 3, b is 0, 1 or 2, and (a+b) is 1, 2 or 3;

[0059] (ii) and may optionally include other silanoxy units of formula (A2):

[0060] (Z) c SiO (4-c) / 2 (A2)

[0061] in:

[0062] -Z has the same meaning as described above, and

[0063] -c indicates the whole, which is 1, 2 or 3.

[0064] According to the present invention, it is reasonable that, for the definition of 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: alkyl groups comprising 1-8 carbon atoms (optionally substituted with at least one halogen atom), and C6-C... 10 An aryl group. Z can advantageously represent a monovalent group selected from: methyl, ethyl, propyl, 3,3,3-trifluoropropyl, xylyl, tolyl, and phenyl. Furthermore, in formula (A1), the symbol Y can advantageously represent a group selected from: vinyl, propenyl, 3-butenyl, and 5-hexenyl. Preferably, the symbol Y is vinyl and the symbol Z is methyl.

[0065] Organopolysiloxane A can have a linear or branched structure, preferably a linear structure. When it is a linear organopolysiloxane, it can be basically composed of the following units:

[0066] - Selected from formula (Y)2SiO 2 / 2 (Y)(Z)SiO 2 / 2 and (Z)2SiO 2 / 2 The silanoxy unit "D" of the unit; and

[0067] - Selected from formula (Y)3SiO 1 / 2 (Y)2(Z)SiO 1 / 2 (Y)(Z)2SiO 1 / 2 and (Z)3SiO 2 / 2The silyloxy group "M" of the unit.

[0068] - In these formulas, the symbols Y and Z are as defined above.

[0069] Preferably, the linear organopolysiloxane A has a degree of polymerization of 2,000 to 10,000, more preferably 2,000 to 8,000, and even more preferably 2,000 to 5,000.

[0070] As examples of unit "D", dimethylsiloxy, methylphenylsiloxy, methylvinylsiloxy, methylbutenylsiloxy, methylhexenylsiloxy, methyldecenylsiloxy, and methyldecadienylsiloxy groups may be mentioned.

[0071] Examples of the unit "M" may include trimethylsilyloxy, dimethylphenylsilyloxy, dimethylvinylsiloxy, and dimethylhexenylsiloxy groups.

[0072] The organopolysiloxane A (especially when it is linear) can be a polymer preferably having a weight-average molecular weight Mw of 400,000 g / mol to 1,000,000 g / mol and more preferably 600,000 g / mol to 900,000 g / mol.

[0073] As an example of a usable organopolysiloxane A, the following can be mentioned:

[0074] - Polydimethylsiloxane with a dimethylvinylsilyl terminus;

[0075] - Poly(methylphenylsiloxane-co-dimethylsiloxane) with dimethylvinylsilyl end groups;

[0076] - Poly(vinylmethylsiloxane-co-dimethylsiloxane) with dimethylvinylsilyl end groups;

[0077] - Poly(dimethylsiloxane-co-vinylmethylsiloxane) with a trimethylsilyl terminus.

[0078] The following type of organopolysiloxane A is particularly advantageous: This organopolysiloxane A is a polydimethylsiloxane containing a dimethylvinylsilyl terminal group, having a weight-average molecular weight Mw of 260,000 g / mol to 1,000,000 g / mol, preferably 600,000 g / mol to 900,000 g / mol. The particularly advantageous organopolysiloxane A is of formula M... Vi D a M Vi Those, among which:

[0079] -M Vi=The silanoxy unit in the following formula: (vinyl)(CH3)2SiO 1 / 2

[0080] -D = the silyloxy group of the following formula: (CH3)2SiO 2 / 2 ,as well as

[0081] -a is a number between 2000 and 6000, and preferably between 3000 and 5500.

[0082] Based on the total amount of components A+B+XL+CE, organopolysiloxane A can be used in an amount of 15-45% by weight, preferably 20-35% by weight.

[0083] According to one embodiment, based on the total weight of organopolysiloxane A, organopolysiloxane A has an alkenyl content of 0.001%-0.5% by weight, preferably 0.005%-0.025% by weight, and more preferably 0.008%-0.018% by weight.

[0084] Preferably, the organopolysiloxane A can be selected from dimethyl vinyl-terminated polydimethylsiloxane, dimethyl vinyl-terminated polydimethylmethylvinylsiloxane, trimethyl-terminated polydimethylmethylvinylsiloxane, and more preferably from dimethyl vinyl-terminated polydimethylsiloxane.

[0085] Component B - Organopolysiloxane resin B, which contains hydroxyl groups bonded to Si atoms.

[0086] To describe polyorganosiloxanes, a nomenclature known in the field of organosilicones is used, employing the following letters to describe the silanoxy unit: M, D, T, and Q. The letter M indicates that the polysiloxane has the formula (R... 1 )3SiO 1 / 2 In a monofunctional unit, a silicon atom is attached to a single oxygen atom in the polymer containing this unit. The letter D indicates a difunctional unit (R... 1 )2SiO 2 / 2 In this structure, a silicon atom is bonded to two oxygen atoms. The letter T indicates that it has the formula (R). 1 SiO 3 / 2 The three functional units, in which silicon atoms are bonded to three oxygen atoms. The letter Q represents the form SiO. 4 / 2 The trifunctional unit, in which a silicon atom is bonded to four oxygen atoms. Symbol R 1 With symbol R 2 The same definition applies. M, D, and T units can be functionalized. Therefore, when referring to M, D, and T units, the specific functional group must be specifically specified.

[0087] The organopolysiloxane resin B containing hydroxyl groups bonded to Si atoms can be selected from conventional organopolysiloxane resins, among which organosilicon resins prepared by co-hydrolysis and co-condensation of chlorosilanes selected from the following: formula (R) 2 )3SiCl、(R 2 )2Si(Cl)2、R 2 chlorosilanes of Si(Cl)3 and Si(Cl)4. These resins are well-known and commercially available branched organopolysiloxane oligomers or polymers. They have at least two compounds selected from formula (R1, R2, R3, R4 ...5, R6, R7, 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 unit) different silanoxy units, wherein at least one of these units is a T unit or a Q unit. Group R 2 The distribution of these groups results in each silicon atom in the resin containing approximately 0.8-1.8 R groups. 2 Furthermore, these resins are not fully condensed and contain OH groups. (Group R) 2 They are the same or different and are selected from C1-C6 linear or branched alkyl, C2-C4 alkenyl, phenyl, and 3,3,3-trifluoropropyl. For example, as alkyl R 2 Examples of the group may include methyl, ethyl, isopropyl, tert-butyl, and n-hexyl, and as an alkenyl group may include vinyl or allyl. Preferably, the group R 2 It is either methyl or hydroxyl.

[0088] According to a specific embodiment, the organopolysiloxane resin B containing hydroxyl groups is selected from:

[0089] a)MQ (OH) Type hydroxylated silicone resin, which comprises silanoxy units M and Q of the following formula. (OH) copolymers:

[0090] -M=R 3 R 4 R 5 SiO 1 / 2 ,and

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

[0092] -Optionally, a silanoxy unit Q=SiO is present. 4 / 2

[0093] b)MD Vi Q (OH) Type hydroxylated silicone resin, which contains silanoxy units M, D of the following formula Vi and Q (OH) copolymers:

[0094] -M=R 3 R 4 R 5 SiO 1 / 2 ,

[0095] -D Vi =(Vi)(R) 3 SiO 2 / 2 ,and

[0096] -Q (OH) =(OH)SiO 3 / 2 ,

[0097] -Optionally, a silanoxy unit Q=SiO is present. 4 / 2

[0098] c)MM Vi Q (OH) Type hydroxylated silicone resin, which contains silanoxy units M, M of the following formula Vi and Q (OH) copolymers:

[0099] -M=R 3 R 4 R 5 SiO 1 / 2 ,

[0100] -M Vi =(Vi)(R) 3 (R) 4 SiO 2 / 2 ,and

[0101] -Q (OH) =(OH)SiO 3 / 2 ,

[0102] -Optionally, a silanoxy unit Q=SiO is present. 4 / 2

[0103] d)MDT (OH) T-type hydroxylated silicone resins are silicone resins containing silanoxy units M, D, and T of the following formula. (OH) copolymers of T:

[0104] -M=R 3 R 4 R 5 SiO 1 / 2 ,

[0105] -D=R 3 R 4 SiO 2 / 2 ,

[0106] -T (OH) =(OH)R 3 SiO 2 / 2 ,

[0107] -T=R 3 SiO 3 / 2 ,as well as

[0108] e)DT (OH) T-type hydroxylated silicone resins are silicone resins containing silanoxy units D and T of the following formula. (OH) copolymers of T:

[0109] -D=R 3 R 4 SiO 2 / 2 ,

[0110] -T (OH) =(OH)R 3 SiO 2 / 2 ,

[0111] -T=R 3 SiO 3 / 2 ,and

[0112] In the formula, the symbol Vi = vinyl group, and the symbol R 3 R 4 and R 5 Selected independently from:

[0113] - A linear or branched alkyl group having 1-8 carbon atoms, including the terminal atoms, and optionally substituted with one or more halogen atoms, preferably selected from methyl, ethyl, isopropyl, tert-butyl, and n-hexyl.

[0114] - An aryl or alkylaryl group having 6-14 carbon atoms including the terminal value, and preferably selected from phenyl, xylyl and tolyl.

[0115] According to a preferred embodiment, as an example of 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 Q and / or T units.

[0116] According to another preferred embodiment, organopolysiloxane resin B is MQ. (OH) MQQ (OH) or MM Vi Q (OH)The product is a hydroxylated silicone resin of the type B, comprising 0.1-4% by weight, preferably 0.3-2.0% by weight, and more preferably 0.5-1.5% 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, more preferably 0.6 to 0.9. Component B may have a weight-average molecular weight Mw of 3000 g / mol to 10000 g / mol, preferably 4000 g / mol to 6000 g / mol.

[0117] In this composition of the present invention, organopolysiloxane resin B can be used as a tackifier.

[0118] Based on the total amount of components A+B+XL+CE, organopolysiloxane resin B can be used in an amount of 15-45% by weight, preferably 25-40% by weight.

[0119] Preferably, the weight ratio between component B and component A can be from 0.8 to 2.5, more preferably from 1.0 to 2.0.

[0120] Component XL - Organopolysiloxane crosslinking agent XL

[0121] Component XL can be called a crosslinking agent, which is an organopolysiloxane having at least three hydrogen atoms bonded to Si.

[0122] For example, the organohydrosiloxane crosslinking agent XL according to the present invention may contain:

[0123] • At least three silyloxy units of formula (XL-1):

[0124] (H)(L) e SiO (3-e) / 2 (XL-1)

[0125] The symbol H represents a hydrogen atom, and the symbol L represents an alkyl group having 1-8 carbon atoms, including the terminal atoms, or C6-C. 10 Aryl group, and the symbol e equals 0, 1, or 2; and

[0126] •Optionally, other silyloxy units of formula (XL-2):

[0127] (L) g SiO (4-g) / 2 (XL-2)

[0128] The symbol L represents an alkyl group having 1-8 carbon atoms, including the terminal value, or C6-C. 10 Aryl, and the symbol g equals 0, 1, 2 or 3, and

[0129] The condition is that each polymer of organopolysiloxane XL contains between 0.5% by weight and 15.0% by weight of Si-H functional groups, preferably between 1.0% by weight and 12.5% ​​by weight of Si-H functional groups, and even more preferably between 1.5% by weight and 10.0% by weight of Si-H functional groups.

[0130] As an organopolysiloxane XL with crosslinking function and usable according to the present invention, formula M can be mentioned. H D x D w H M H M H D x D y H M and MD x D z H Those of M in these formulas:

[0131] -M H =The silanoxy unit in the following formula: (H)(CH3)2SiO 1 / 2

[0132] -D H =The silanoxy unit in the following formula: (H)(CH3)SiO 2 / 2

[0133] -D = the silyloxy group of the following formula: (CH3)2SiO 2 / 2 ,and

[0134] -M = the silyloxy group of the following formula: (CH3)3SiO 1 / 2

[0135] -in

[0136] x is a number between 0 and 500, preferably between 2 and 250, and more preferably between 5 and 80.

[0137] ·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;

[0138] ·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

[0139] • 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.

[0140] Each polymer contains between 0.5% by weight and 15.0% by weight of Si-H functional groups, preferably between 1.0% by weight and 12.5% ​​by weight of Si-H functional groups, and even more preferably between 1.5% by weight and 10.0% by weight of Si-H functional groups.

[0141] By adjusting the viscosity of component XL, this medical silicone pressure-sensitive adhesive composition can be applied more specifically to a variety of particular substrates, thereby producing good performance in the final application of PSA.

[0142] Component XL may have a dynamic viscosity of 40-1000 mPa·s at 25°C, preferably 50-750 mPa·s at 25°C, and more preferably 60-500 mPa·s at 25°C. If the viscosity of component XL is less than 40 mPa·s at 25°C, the cohesive force of the cured PSA is too strong to be easily torn, and the strong cohesive force will result in weak adhesion to the substrate, so that the cured PSA layer will leave fragmented residue on the skin when it is peeled off.

[0143] Based on the total weight of component XL, component XL may have a Si-H content of 0.5% to 15% by weight, preferably 1.0% to 12.5% ​​by weight, and more preferably 1.5% to 10.0% by weight.

[0144] Preferably, the organopolysiloxane crosslinking agent XL can be a trimethylsiloxy-terminated polymethylhydrosiloxane or a dimethylhydrosiloxane-terminated polymethylhydrosiloxane.

[0145] Component CE - Organic polysiloxane chain extender CE

[0146] Component CE can be called a chain extender, which is an organopolysiloxane with exactly two terminal hydrogen atoms bonded to Si.

[0147] For example, the organohydrosiloxane chain extender CE according to the present invention may contain:

[0148] - Two terminal silyloxy units of formula (CE-1) that may be the same or different:

[0149] (H) p (R 6 ) q SiO 1 / 2 (CE-1)

[0150] in:

[0151] - Symbol R 6 Corresponding to C1-C8 alkyl groups or C6-C 10 aryl group;

[0152] - And the symbol H represents a hydrogen atom, where p = 1 and q = 2;

[0153] - At least one silyloxy unit of formula (CE-2):

[0154] (H) n (R 7 ) m SiO 2 / 2 (CE-2)

[0155] Wherein group R 7 Corresponding to C1-C8 alkyl groups or C6-C 10 An aryl group, with the symbol H representing a hydrogen atom, where n = 0, m = 2, and

[0156] The condition is that each organopolysiloxane CE polymer contains two hydrogen atoms, each bonded to a different silicon atom, and preferably, each organopolysiloxane CE polymer contains two siloxy units of formula (CE-1) where p=1 and at least one siloxy unit of formula (CE-2) where n=0.

[0157] As an example of an organopolysiloxane CE with "chain extender" function, polydimethylsiloxane containing a dimethylhydrosilyl end group can be mentioned, which has a dynamic viscosity at 25°C of 1 mPa·s to 1000 mPa·s at 25°C, preferably 5 mPa·s to 500 mPa·s at 25°C, and even more preferably 5-300 mPa·s at 25°C. Particularly advantageous organopolysiloxane CEs have the formula M H D x M H ,in:

[0158] -M H =The silanoxy unit in the following formula: (H)(CH3)2SiO 1 / 2

[0159] -D = the silyloxy group of the following formula: (CH3)2SiO 2 / 2 ,and

[0160] -x is an integer from 1 to 200, preferably from 1 to 150, or even more preferably from 3 to 120.

[0161] Organopolysiloxanes (CEs) are described as "chain extenders" because they are assumed to increase the pore size of the network during crosslinking when the SiH reactive functional groups are located at the chain ends.

[0162] The component CE may have a dynamic viscosity of 1-1000 mPa·s at 25°C, preferably 5-500 mPa·s at 25°C, and more preferably 5-300 mPa·s at 25°C.

[0163] Based on the total weight of component CE, component CE may have a Si-H content of 0.2% to 10% by weight, preferably 0.3% to 8.0% by weight, and more preferably 0.4% to 6.0% by weight.

[0164] Preferably, the organopolysiloxane chain extender CE can be a dimethyl hydrogen-terminated polydimethylsiloxane.

[0165] Organopolysiloxane crosslinking agent XL and organopolysiloxane chain extender CE can be introduced into the compositions of the present invention in any suitable form. For example, organopolysiloxane crosslinking agent XL and organopolysiloxane chain extender CE can be used alone or as a mixture.

[0166] When the organopolysiloxane crosslinking agent XL and the organopolysiloxane chain extender CE are introduced in the form of a mixture, the mixture is introduced in an amount of 1.0-5.0% by weight, preferably 1.0-2.0% by weight, based on the total amount of components A+B+XL+CE. The mixture can have a dynamic viscosity of at least 70 mPa·s at 25°C.

[0167] Component D-hydrosilanization catalyst D

[0168] As a hydrosilylation catalyst D usable according to the present invention, compounds belonging to the platinum group metals known to those skilled in the art may be mentioned. The platinum group metals are those referred to as platinoids, a term that includes ruthenium, rhodium, palladium, osmium, and iridium in addition to platinum. Compounds of platinum and rhodium are preferred. Complexes of platinum and organic products described in patents US-A-3159 601, US-A-3 159 602, and US-A-3 220 972, and European patents EP-A-0 057459, EP-A-0 188 978, and EP-A-0 190 530, and complexes of platinum and vinyl organosiloxanes described in patent US-A-3 419 593 are particularly useful. Platinum is generally the preferred catalyst. Examples of examples that may be mentioned in particular include platinum black, chloroplatinic acid, alcohol-modified chloroplatinic acid, complexes of chloroplatinic acid with olefins, aldehydes, vinylsiloxanes, or alkynyl alcohols. Preferably, Karstedt solutions or complexes as described in patent US-A-3 775 452, chloroplatinic acid hexahydrate, or platinum catalysts containing carbene ligands are preferred.

[0169] Preferably, component D is a solution of a platinum complex in vinyl-terminated polydimethylsiloxane.

[0170] Component E - Solvent E

[0171] According to one embodiment of the present invention, solvent E is selected from: aliphatic C6-C16 Hydrocarbons, polydimethylsiloxanes containing trimethylsilyl end groups with a viscosity of 0.65-5 mPa·s at 25°C, cyclic polydimethylsiloxanes, (3-octyl)heptamethyltrisiloxane, toluene, xylene, C1-C8 alkyl esters, C2-C4 carboxylic acids and mixtures thereof.

[0172] Specifically, 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, and more preferably ethyl acetate for healthcare applications.

[0173] The amount of solvent E is 30% to 80% of the total weight of the composition, preferably 40% to 70% by weight.

[0174] Component F-hydrosilaneization inhibitor F

[0175] Hydrosilylation inhibitor F is used in the compositions of the present invention.

[0176] As inhibitors of hydrosilylation reactions available according to the present invention, those selected from the following can be mentioned: α-alkynyl alcohols, α,α'-alkynyl diesters, conjugated enyne compounds, α-alkynyl ketones, acrylonitriles, maleic esters, fumarates, and mixtures thereof. These compounds capable of acting as inhibitors of hydrosilylation are well known to those skilled in the art. They can be used alone or as mixtures.

[0177] α-Alynyl alcohol type inhibitors can be selected from compounds of the following formula (F1):

[0178] (R 8 (R) 9 C(OH)-C≡CH(F1)

[0179] in:

[0180] -Group R 8 Indicates alkyl group, cycloalkyl group, (cycloalkyl)alkyl group, C6-C 10 aryl group or C7-C 18 arylalkyl groups,

[0181] -Group R 9 Represents hydrogen atoms, alkyl groups, cycloalkyl groups, (cycloalkyl)alkyl groups, C6-C 10 aryl group or C7-C 18 arylalkyl groups,

[0182] -or R 8 and R 9 Together with the carbon atoms they are attached to, they form 5, 6, 7, or 8-membered aliphatic rings, which may be substituted once or multiple times.

[0183] According to equation (F1):

[0184] - The term "alkyl" refers to a saturated hydrocarbon chain containing 1-20 carbon atoms, preferably 1-8 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;

[0185] - According to the present invention, the term "cycloalkyl" refers to a saturated hydrocarbon group comprising 3-20 carbon atoms, preferably 5-8 carbon atoms, in a monocyclic or polycyclic, preferably monocyclic or bicyclic manner. When the cycloalkyl group is polycyclic, multiple cyclic nuclei may be connected to each other by covalent bonds and / or by spin atoms, and / or fused together. The cycloalkyl group may be selected from cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, adamantane, and norbornene;

[0186] -According to the invention, the term "(cycloalkyl)alkyl" refers to a cycloalkyl group, also defined above, attached to an alkyl group as defined above;

[0187] - According to the present invention, "aryl" refers to a monocyclic or polycyclic aromatic hydrocarbon group containing 6-10 carbon atoms. The aryl group may be selected from phenyl, naphthyl, and anthracene.

[0188] - According to the invention, the term "arylalkyl" refers to an aryl group, also defined above, attached to an alkyl group as defined above.

[0189] According to a preferred embodiment, in equation (F1), R 8 and R 9 Together with the carbon atoms they are attached to, they form unsubstituted 5, 6, 7, or 8-membered aliphatic rings. According to another preferred embodiment, R... 8 and R 9 Whether they are the same or different, they independently represent monovalent C1-C. 12 Preferably, C1-C6 alkyl groups are used.

[0190] The inhibitor of α-alkynols available according to the present invention may 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-heptyyn-3-ol; 3-methyl-1-octyyn-3-ol; 3-methyl-1-nonyn-3-ol; 3-methyl-1-decyn-3-ol; 3-methyl-1-dodecyn-3-ol; 3-methyl-1-pentadenyyn-3-ol; 3-ethyl-1-pentyn-3-ol; 3-ethyl -1-Hexyn-3-ol; 3-Ethyl-1-heptyyn-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-heptyyn-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-Hepyn-3-ol; 5-Methyl-1-hexyn-3-ol; 4-Ethyl-1-octyyn-3-ol and 9-ethynyl-9-fluorenol.

[0191] Inhibitors of the α,α'-acetylacetic diester type can be selected from compounds of the following formula (F2):

[0192]

[0193] Wherein group R 10 and R 11 They can be identical or different, and can be used independently to represent alkyl groups, cycloalkyl groups, (cycloalkyl)alkyl groups, and C6-C groups. 10 Aryl group, C7-C 18 Arylalkyl groups or silylalkyl groups.

[0194] According to the invention, the term "silyl" refers to a group of the formula –SiR3, wherein each symbol R independently represents an alkyl group comprising 1-20 carbon atoms, preferably 1-8 carbon atoms. A silyl group may be, for example, a trimethylsilyl group.

[0195] According to a specific implementation scheme, in equation (F2), R 10 and R 11 Whether they are the same or different, they are represented independently of each other as C1-C. 12Preferably, it contains C1-C6 alkyl groups or trimethylsilyl groups. The inhibitors of α,α'-acetylene diesters available according to the present invention may be selected from the following compounds: dimethyl acetylenate-dicarboxylate (DMAD), diethyl acetylenate-dicarboxylate, tert-butyl acetylenate-dicarboxylate, and bis(trimethylsilyl) acetylenate-dicarboxylate.

[0196] Conjugated ene-yne ​​inhibitors can be selected from compounds of formula (F3):

[0197]

[0198] in:

[0199] -Group R 12 R 13 and R 14 Each of these can be used independently to represent a hydrogen atom, alkyl group, cycloalkyl group, (cycloalkyl)alkyl group, C6-C. 10 aryl group or C7-C 18 arylalkyl groups,

[0200] -or from 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, which may optionally be substituted once or multiple times.

[0201] According to a specific implementation scheme, group R 12 R 13 and R 14 Each hydrogen atom is represented independently, C1-C 12 Preferably, it has C1-C6 alkyl groups, or C6-C 10 Aryl group. The inhibitor of the conjugated enyne compound available according to the invention may be selected from the following compounds: 3-methyl-3-penten-1-yne; 3-methyl-3-hexen-1-yne; 2,5-dimethyl-3-hexen-1-yne; 3-ethyl-3-buten-1-yne; and 3-phenyl-3-buten-1-yne. According to another specific embodiment, it is selected from the group R. 12 R 13 and R 14 The two groups together with the carbon atoms they are attached to form an unsubstituted 5, 6, 7, or 8-membered aliphatic ring, and the remaining third group represents a hydrogen atom or a C1-C ring. 12 Preferably, C1-C6 alkyl groups are used. 1-Ethynyl-1-cyclohexene can be used as an inhibitor of the conjugated enyne compound available according to the present invention.

[0202] α-Alynone type inhibitors can be selected from compounds of the following formula (F4):

[0203]

[0204] Where R 15 Indicates alkyl group, cycloalkyl group, (cycloalkyl)alkyl group, C6-C 10 aryl group or C7-C 18 An arylalkyl group, which may optionally be substituted once or multiple times with a chlorine, bromine or iodine atom.

[0205] According to a preferred embodiment, R 15 Indicates monovalent C1-C 12 Preferably, C1-C6 alkyl groups, optionally substituted once or multiple times with chlorine or bromine atoms, or cycloalkyl groups, or C6-C 10 Aryl group. The inhibitors of α-alkynones available according to the present invention may be selected from the following compounds: 1-octyno-3-one, 8-chloro-1-octyno-3-one; 8-bromo-1-octyno-3-one; 4,4-dimethyl-1-octyno-3-one; 7-chloro-1-heptyno-3-one; 1-hexyn-3-one; 1-pentyn-3-one; 4-methyl-1-pentyn-3-one; 4,4-dimethyl-1-pentyn-3-one; 1-cyclohexyl-1-propyn-3-one; benzo[a]acetylene and o-chlorobenzoylacetylene.

[0206] Acrylonitrile-type inhibitors can be selected from compounds of the following formula (F5):

[0207]

[0208] Where R 16 and R 17 Each of these can be independently represented by a hydrogen atom, chlorine, bromine or iodine atom, alkyl group, cycloalkyl group, (cycloalkyl)alkyl group, C6-C. 10 aryl group or C7-C 18 An arylalkyl group, which may optionally be substituted once or multiple times with a chlorine, bromine or iodine atom.

[0209] As an inhibitor of acrylonitrile available according to the present invention, the following compounds may be selected: acrylonitrile; methacrylonitrile; 2-chloroacrylonitrile; crotonitrile and cinnamonitrile.

[0210] Inhibitors of the maleate or fumarate type can be selected from compounds of formulas (F6) and (F7):

[0211]

[0212] Where R 18 and R19 They may be the same or different, representing alkyl or alkenyl groups, cycloalkyl groups, (cycloalkyl)alkyl groups, C6-C, independently of each other. 10 aryl group or C7-C 18 The arylalkyl group, wherein the alkyl, alkenyl, cycloalkyl, (cycloalkyl)alkyl, aryl and arylalkyl groups may be substituted with an alkoxy group.

[0213] According to the present invention, the term "alkenyl" refers to a saturated hydrocarbon chain containing 2-6 carbon atoms and having at least one degree of diunsaturation. 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.

[0214] According to a specific implementation scheme, R 18 and R 19 Whether they are the same or different, they are represented independently of each other as C1-C. 12 Preferably, C1-C6 alkyl or alkenyl groups are used, optionally substituted with C1-C6 alkoxy groups.

[0215] As an inhibitor of maleate or fumarate available according to the present invention, diethyl fumarate, diallyl fumarate, diallyl maleate and bis(methoxyisopropyl) maleate may be selected.

[0216] The amount of these inhibitors added relative to the total organosilicon composition is 1-50,000 ppm by weight, particularly 10-10,000 ppm, preferably 20-2000 ppm, and even more preferably 800-2000 ppm.

[0217] The medical silicone pressure-sensitive adhesive composition according to the present invention can be applied to a variety of substrates suitable for medical applications. Depending on the application field, the substrate can be a carrier with very different properties.

[0218] According to a preferred embodiment, the substrate is a woven, nonwoven, or knitted textile, or a plastic film. The term "nonwoven" refers to any structure made of textile materials such as fibers, continuous filaments, or cut yarns (regardless of their nature or origin), which is shaped into a mesh and connected in any way to exclude the interlacing of yarns. Nonwoven textiles are products that have the appearance of a porous textile composed primarily of fibers and are produced by methods other than spinning, weaving, knitting, or knotting.

[0219] 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 invention. Examples include: polyvinyl chloride, polypropylene, regenerated cellulose, polyethylene terephthalate (PET), and polyurethane, particularly 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 blown melt polyurethane. When the substrate is a flexible polyurethane film, the thickness is typically 5-600 μm, preferably 5-250 μm, and more preferably 10-100 μm.

[0220] Preferably, the substrate can be selected from paper, polyurethane, nonwoven fabric and elastic fabric.

[0221] Depending on the end application, the medical silicone pressure-sensitive adhesive composition according to the present invention is suitable for a variety of substrates. In particular, organopolysiloxanes A, CE, and XL can be selected such that a specific molar ratio RHAlk = tH / tAlk and a specific ratio nH XL / nH CE It can be more specifically applied to certain substrates.

[0222] For example, when the substrate is paper, the molar ratio RHAlk = tH / tAlk can be from 4.30 to 6.00, preferably from 4.55 to 5.55; and / or the molar ratio nH XL / nH CE It can be from 0.10 to 0.22, preferably from 0.12 to 0.20.

[0223] When the substrate is thermoplastic polyurethane, the molar ratio RHAlk=tH / tAlk can be from 4.50 to 8.00, preferably from 4.70 to 5.70; and / or the molar ratio nH XL / nH CE It can be from 0.50 to 11.0, preferably from 1.2 to 8.0.

[0224] When the substrate is a nonwoven fabric, the molar ratio RHAlk=tH / tAlk can be from 3.50 to 8.00, preferably from 4.00 to 6.60; and / or the molar ratio nH XL / nH CE It can be from 1.00 to 7.50, preferably from 1.20 to 6.50.

[0225] When the substrate is an elastic fabric (preferably for kinesiological motion belts), the molar ratio RHAlk = tH / tAlk can be from 4.10 to 8.00, preferably from 5.00 to 6.60; and / or the molar ratio nH XL / nH CE It can be from 0.50 to 11.00, preferably from 2.00 to 8.00.

[0226] Those skilled in the art can adjust the medical silicone pressure-sensitive adhesive composition according to the end application. Typically, the medical silicone pressure-sensitive adhesive composition according to the present invention may have a dynamic viscosity of 500-5000 mPa·s at 25°C, preferably 800-3000 mPa·s at 25°C, and more preferably 1000-2500 mPa·s at 25°C.

[0227] The medical silicone pressure-sensitive adhesive composition according to the invention can be applied or coated onto various substrates using any technique well known to those skilled in the art. As a technique for depositing the medical silicone pressure-sensitive adhesive composition according to the invention, coating techniques implemented, for example, by using a doctor blade, especially a roller-lined doctor blade, an air-floating blade, and a lined doctor blade, or by padding, i.e., by pressing between two rollers, or by using a licking roller, a rotating machine, a reversing roller, or a transfer, or by spraying. As another coating technique, curtain coating can be mentioned. Curtain coating is a method of applying a coating liquid to an article or carrier. Curtain coating is characterized by the formation of a curtain of coating liquid that falls freely from the lip of a hopper and encounters an article moving through the curtain under gravity to form a coating layer. This technique has been widely used in the field of preparing multilayer photosensitive silver carriers (see, for example, patents US-3 508 947, US 3 508 947, or EP 537086).

[0228] Then, the medical silicone pressure-sensitive adhesive composition coated on the substrate is crosslinked, for example at a temperature of 100°C-160°C, preferably 120°C-150°C.

[0229] Therefore, the substrate coated with silicone pressure-sensitive adhesive G is obtained by crosslinking the silicone pressure-sensitive adhesive composition according to the present invention. Detailed Implementation

[0230] Other advantages and features of the invention will become apparent when reading the following embodiments, which are given by way of illustration and are by no means limiting.

[0231] Example

[0232] 1. Measurement Method

[0233] The measurement methods used in the embodiments will be described below.

[0234] 1.1. Easy to tear (Easy to tear)

[0235] The "tearability" test is conducted as follows: The cured PSA laminate is cut into strips measuring 10cm (length) x 2.5cm (width). The release liner is removed from the PSA layer, and the strip is then quickly torn along its width. The tearability test results are categorized into three levels based on the observed breakage.

[0236] A = Clean tear without stringing, acceptable.

[0237] B = Difficult to break when torn and does not string, acceptable.

[0238] C = Difficult to break and stringy when torn, unacceptable.

[0239] 1.2 Residual on skin

[0240] The "residue on skin" test is conducted as follows: Cured PSA laminate is cut into 5cm (length) x 2.5cm (width) strips. The release liner is removed from the PSA layer, and the PSA layer is then adhered to the skin. After 4 hours at room temperature, the PSA layer is peeled off, and the adhered area on the skin is examined. The "residue on skin" test results are graded into 5 levels:

[0241] A = No visible adhesive and no sticky feeling on the fingers, acceptable.

[0242] B = No visible adhesive and minimal stickiness to the fingers, acceptable.

[0243] C = Visible adhesive spot, unacceptable

[0244] D = Visible adhesive fragments, unacceptable

[0245] E = Adhesive visible throughout the entire adhesion area, unacceptable.

[0246] 1.3 Anchorage on substrate

[0247] The "anchoring on substrate" test is conducted as follows: The cured PSA laminate is cut into strips measuring 10cm (length) x 2.5cm (width). The release liner is removed from the PSA layer, the adhesive side is folded to bond the ends together, and then they are quickly peeled apart. By observing the adhesion areas at both ends, the "anchoring on substrate" test results are categorized into four levels:

[0248] A = No change in either adhesion region, acceptable.

[0249] B = Adhesive breakage in any adhesion area is acceptable.

[0250] C = Adhesive fragments peeling off from the substrate in any adhesion area is unacceptable.

[0251] D = Adhesive completely peels off the substrate in any adhesion area, unacceptable.

[0252] 1.4 Peel Adhesion

[0253] The "peel adhesion" test was conducted as follows: Cured PSA laminate was cut into 10cm (length) × 2.5cm (width) strips. The release liner was removed from the PSA layer. The PSA layer was then adhered to a 15cm × 5cm piece of hard textured paper, and the strips were laminated twice using a 2kg rubber roller. The "prepared for test" samples were then left to stand for 20 minutes. Peel adhesion was then performed according to FINA TFTM1 on a Cheminstrument Co. Ltd. PA1000-180 Peel Tester. The atmospheric conditions were 23°C and 50% RH.

[0254] A result greater than 4N / 25mm is acceptable.

[0255] 1.5 Probe Tack Test

[0256] The probe tack test was performed as follows: the cured PSA laminate was cut into strips of 2.5 cm (length) x 2.5 cm (width), and the release liner was removed from the PSA layer. The tack test was conducted using a PT1000 Probe Tack Tester from Cheminstrument Co. Ltd., according to ASTM D2979. The atmospheric conditions were 23°C and 50% RH.

[0257] When the result is greater than 1000g / cm 2 At that time, it is acceptable

[0258] 1.6 Loop Tack Test

[0259] The "ring tack test" was conducted as follows: the cured PSA laminate was cut into strips measuring 10 cm (length) × 2.5 cm (width), and the release liner was removed from the PSA layer. The test was performed using a Cheminstrument Co. Ltd. LT1000 Loop Tack Tester according to FINAT FTM9. The atmospheric conditions were 23°C & 50% RH.

[0260] When the result is greater than 500g / 25mm 2 At that time, it is acceptable

[0261] 1.7 Reposition property

[0262] "Re-attachment performance" was assessed using either a ring tack or probe tack test. The tack test was repeated using the same sample until a 40% loss of tack was observed compared to the first result; the number of cycles was then recorded as an indicator of re-attachment performance. The atmospheric conditions were 23°C and 50% RH.

[0263] A result greater than 4 is acceptable.

[0264] 1.8 Release Force

[0265] The peel strength test was conducted as follows: The cured PSA laminate was cut into strips measuring 10cm (length) x 2.5cm (width). The release liner was removed from the PSA layer. The PSA layer was then adhered to a standard fluoropolymer release liner measuring 15cm x 5cm, and these strips were laminated for two cycles using a 2kg rubber roller. The "prepared for testing" samples were then left to stand for 20 minutes. Then, according to FINA TFTM3, the peel strength was determined using a PA1000-180 Peel Tester from Cheminstrument Co. Ltd. when the PSA was peeled from the selected liner. The atmospheric conditions were 23°C and 50% RH.

[0266] Results less than 5g / 25mm are acceptable.

[0267] 2. Preparation of the composition of the present invention

[0268] 2.1 The raw materials used in the examples are listed in Table 1 below:

[0269] Table 1

[0270]

[0271] 2.2 Preparation of "Ready-to-coat" solutions

[0272] 37g of organopolysiloxane resin B and 0.12g of ECH were uniformly dissolved in 40g of ethyl acetate. Then, 23g of organopolysiloxane A was introduced into the ethyl acetate solution under stirring until all components were uniformly mixed to obtain the basic composition.

[0273] The composition according to the invention is obtained by weighing 100g of the basic composition into 50g of ethyl acetate, then adding crosslinking agent XL and chain extender CE in the amounts shown in the table below, mixing them uniformly, then adding catalyst D in the amounts shown in the table below, and mixing the mixture to obtain a homogeneous solution, referred to as a "ready-to-use" solution.

[0274] 3. Application on substrates

[0275] 3.1 Application 1, Paper Tape

[0276] The process involves first coating a ready-to-use solution onto a fluorosilicone release liner to achieve a dry PSA thickness of 30 μm, then placing it in a fume hood for 10 minutes, followed by 5 minutes in an oven at 120°C. Once the cured layer is removed from the oven, the PSA layer is covered with nonwoven paper, and the resulting sandwich-type assembly is then laminated twice using an automated laminator at 30 psi pressure. The PSA is then transferred to the desired substrate side. The cured PSA laminate is then obtained.

[0277] Table 2 Examples of coating on paper substrates

[0278]

[0279] Exm.5 to Exm.6 to 8: RHAlk < 4.30 (although the same nH XL / nH CE This leads to weak cohesion (weak cross-linking) and leaves spotting residue on the skin.

[0280] Exm.12 versus Exm.2 and 4: nH XL / nH CE A value >0.22 (despite the same RHAlk) results in such strong cohesion that the adhesion to the substrate is too weak and the anchoring test fails.

[0281] Exm.9 to 12: nH XL / nH CE A value >0.22 (regardless of the RHAlk value) results in such strong cohesion that the adhesion to the substrate is too weak and the anchoring test fails. Worse still, some PSA fragments remain on the skin after the PSA tape is peeled off.

[0282] It can be seen that in nH XL / nH CE Within the range of 0.10 to 0.22 and RHAlk of 4.3 to 6.0, it achieves good performance on paper substrates, namely easy tearing, good re-adhesion and water resistance, good anchoring on substrates, and low skin irritation.

[0283] 3.2 Application 2, TPU transparent patch.

[0284] The process involves coating a ready-to-use solution onto a TPU film (backed by polyethylene-coated kraft paper) to achieve a dry PSA thickness of 30 μm. The film is then quickly placed in a 60°C oven for 1 minute, followed by a 120°C oven for 5 minutes. After removing the cured layer from the oven, the cured PSA layer and a fluorosilicone release liner (Si-F liner) are laminated twice under 30 psi pressure. This yields a cured PSA laminate.

[0285] Table 3 Examples of coating on TPU substrate

[0286]

[0287] Exm. 13 to 15: nH XL / nH CE A value <0.50 results in weak cohesion or makes curing impossible, and the failure of cohesion leads to adhesive spots remaining on the skin after the PSA is peeled off.

[0288] Exm. 23 to 25: nH XL / nH CE >11 results in excessive cohesion and weak adhesion to the substrate, leading to anchoring failure when the PSA patch is peeled off the skin. Some adhesive fragments transfer from the substrate to the skin.

[0289] It can be seen that in nH XL / nH CE Within the range of 0.5 to 11 and RHAlk of 4.5 to 8.0, good performance is achieved on TPU substrates, namely good air permeability, good shear properties and water resistance, low irritation during long-term wear, and good anchoring on substrates. In particular, no PU primer is required.

[0290] 3.3 Application 3, nonwoven tape.

[0291] The substrate is a nonwoven fabric.

[0292] The process involves coating a "ready-to-use" solution onto a fluoropolymer release liner to achieve a dry PSA thickness of 36 μm, then placing it in a fume hood for 10 minutes. It is then laminated twice with a nonwoven fabric under 30 psi pressure. The resulting sandwich assembly is then placed in a 120°C oven for 5 minutes and finally removed. The PSA is transferred to the desired substrate side, resulting in a cured PSA laminate.

[0293] Table 4 Examples of coating on nonwoven fabric substrates

[0294]

[0295] Exm. 27 to 29: nH XL / nHCE A value <1.0 results in weak cohesion and leads to adhesive residue spots on the skin after the PSA strip is peeled off.

[0296] Exm.40 to 41: nH XL / nH CE >7.5 results in excessively high peel force and strong cohesion from the liner, leading to poor anchoring on the substrate (resulting in residual PSA fragments on the skin due to weak adhesion to the substrate).

[0297] It can be seen that in nH XL / nH CE Within the range of 1.00 to 7.50 and RHAlk of 3.5 to 8.0, good performance is obtained on nonwoven substrates, namely good air permeability, good shear properties and water resistance, and good anchoring on substrates.

[0298] 3.4 Application 4: Elastic Fabric Tape

[0299] Perform the same process as in Application 3 to obtain the cured PSA laminate. The substrate is an elastic fabric made of cotton or nylon.

[0300] Table 5 Examples of coating on elastic fabric substrates

[0301]

[0302] Exm.45 vs. Exm.46, Exm.47 vs. Exm.48: RHAlk < 4.10 results in weak cohesion, leading to adhesive residue spots on the skin after the PSA strip is peeled off.

[0303] Exm.42 to Exm.44, Exm.43 to Exm.46: nH XL / nH CE A value <0.50 results in weak cohesion, leading to adhesive residue spots on the skin after the PSA strip is peeled off.

[0304] It can be seen that in nH XL / nH CE Within the range of 0.5 to 11 and RHAlk of 4.1 to 8.0, good performance is obtained on elastic fabric substrates, namely good sweat resistance, re-adhesion performance, air permeability, and low irritation during long-term wear.

Claims

1. A medical-grade silicone pressure-sensitive adhesive composition, comprising: - At least one organopolysiloxane A, each molecule of which contains at least two C2-C6 alkenyl groups, each bonded to a silicon atom. - At least one organopolysiloxane resin B, which contains OH groups bonded to silicon atoms. - At least one organopolysiloxane crosslinking agent XL, having at least three hydrogen atoms bonded to silicon atoms, - At least one organopolysiloxane chain extender CE having exactly two terminal hydrogen atoms bonded to silicon atoms, - At least one hydrogenation silylation catalyst D, - At least one solvent E, - At least one hydrosilylation inhibitor F, Organopolysiloxanes A, CE, and XL were selected such that the molar ratio RHAlk = tH / tAlk was 3.5 to 8.0; and nH XL / nH CE It ranges from 0.13 to 11, where: - tH = the number of hydrogen atoms directly bonded to the silicon atoms of organopolysiloxanes XL and CE; - tAlk = the number of alkenyl groups directly bonded to the silicon atoms of organopolysiloxane A; - nH XL = The number of hydrogen atoms directly bonded to the silicon atoms of organopolysiloxane XL; - nH CE = The number of moles of hydrogen atoms that are directly bonded to the silicon atoms of the organopolysiloxane CE.

2. The composition according to claim 1, wherein the organopolysiloxane A is an organopolysiloxane adhesive with a consistency of 200 mm / 10 to 2000 mm / 10 at 25°C, and / or an organopolysiloxane adhesive having a viscosity greater than 600,000 mPa·s at 25°C, and / or an organopolysiloxane adhesive having an alkenyl content of 0.001% to 0.5% by weight based on the total weight of organopolysiloxane A.

3. The composition according to claim 2, wherein the organopolysiloxane A is an organopolysiloxane adhesive with a consistency of 300 mm / 10 to 1800 mm / 10 at 25°C.

4. The composition according to claim 2, wherein the organopolysiloxane A is an organopolysiloxane adhesive with a consistency of 500 mm / 10 to 1500 mm / 10 at 25°C.

5. The composition according to claim 2, wherein the organopolysiloxane A is an organopolysiloxane adhesive having a viscosity greater than 1,000,000 mPa·s at 25°C.

6. The composition according to claim 2, wherein the organopolysiloxane A is an organopolysiloxane adhesive having an alkenyl content of 0.005%-0.025% by weight based on the total weight of organopolysiloxane A.

7. The composition according to claim 2, wherein the organopolysiloxane A is an organopolysiloxane adhesive having an alkenyl content of 0.008%-0.018% by weight based on the total weight of organopolysiloxane A.

8. The composition according to any one of claims 1-7, wherein the molar ratio RHAlk = tH / tAlk is 4.30 to 6.00; and / or the molar ratio nH XL / nH CE The concentration is 0.13 to 0.22, and the composition is coated on paper.

9. The composition according to any one of claims 1-7, wherein the molar ratio RHAlk = tH / tAlk is 4.55 to 5.55; and / or the molar ratio nH XL / nH CE The concentration is 0.13 to 0.20, and the composition is coated on paper.

10. The composition according to any one of claims 1-7, wherein the molar ratio RHAlk = tH / tAlk is 4.50 to 8.00; and / or the molar ratio nH XL / nH CE The concentration is 0.50 to 11.0, and the composition is coated onto polyurethane.

11. The composition of claim 10, wherein the polyurethane is a thermoplastic polyurethane.

12. The composition according to any one of claims 1-7, wherein the molar ratio RHAlk = tH / tAlk is 4.70 to 5.70; and / or the molar ratio nH XL / nH CE The value is 1.2 to 8.0, and the composition is coated on polyurethane.

13. The composition of claim 12, wherein the polyurethane is a thermoplastic polyurethane.

14. The composition according to any one of claims 1-7, wherein the molar ratio RHAlk = tH / tAlk is 3.50 to 8.00; and / or the molar ratio nH XL / nH CE The value is 1.00 to 7.50, and the composition is coated on a nonwoven fabric.

15. The composition according to any one of claims 1-7, wherein the molar ratio RHAlk = tH / tAlk is 4.00 to 6.60; and / or the molar ratio nH XL / nH CE The value is 1.20 to 6.50, and the composition is coated on a nonwoven fabric.

16. The composition according to any one of claims 1-7, wherein the molar ratio RHAlk = tH / tAlk is 4.10 to 8.00; and / or the molar ratio nH XL / nH CE The concentration is 0.50 to 11.00, and the composition is coated on an elastic fabric.

17. The composition according to any one of claims 1-7, wherein the molar ratio RHAlk = tH / tAlk is 5.00 to 6.60; and / or the molar ratio nH XL / nH CE The value is 2.00 to 8.00, and the composition is coated on an elastic fabric.

18. The composition according to any one of claims 1-7, wherein the organopolysiloxane crosslinking agent XL and the organopolysiloxane chain extender CE are introduced in the form of a mixture.

19. The composition according to any one of claims 1-7, wherein the organopolysiloxane crosslinking agent XL has a dynamic viscosity of 40-1000 mPa·s at 25°C; and / or the organopolysiloxane chain extender CE has a dynamic viscosity of 1-1000 mPa·s at 25°C.

20. The composition according to claim 19, wherein the organopolysiloxane crosslinking agent XL has a dynamic viscosity of 50-750 mPa·s at 25°C.

21. The composition according to claim 19, wherein the organopolysiloxane crosslinking agent XL has a dynamic viscosity of 60-500 mPa·s at 25°C.

22. The composition according to claim 19, wherein the organopolysiloxane chain extender CE has a dynamic viscosity of 5-500 mPa·s at 25°C.

23. The composition according to claim 19, wherein the organopolysiloxane chain extender CE has a dynamic viscosity of 5-300 mPa·s at 25°C.

24. The composition according to any one of claims 1-7, wherein the organopolysiloxane resin B is MQ. (OH) MQQ (OH) or MM Vi Q (OH) The type of hydroxylated silicone resin, and containing 0.1-4% by weight of hydroxyl groups relative to the dry weight of organopolysiloxane resin B, and / or the ratio of M units to Q units is 0.5 to 1.

2.

25. The composition according to claim 24, wherein the organopolysiloxane resin B comprises 0.3-2.0% by weight of hydroxyl groups relative to the dry weight of the organopolysiloxane resin B.

26. The composition according to claim 24, wherein the organopolysiloxane resin B comprises 0.5-1.5% by weight of hydroxyl groups relative to the dry weight of the organopolysiloxane resin B.

27. The composition according to claim 24, wherein the ratio of M units to Q units is 0.6 to 0.

9.

28. The composition according to any one of claims 1-7, wherein the weight ratio between organopolysiloxane resin B and organopolysiloxane A is 0.8 to 2.

5.

29. The composition according to claim 28, wherein the weight ratio between organopolysiloxane resin B and organopolysiloxane A is 1.0 to 2.

0.

30. A method of coating a substrate using the composition according to any one of the preceding claims.

31. A coated substrate obtained by using the method according to claim 30.

32. A substrate coated with a silicone pressure-sensitive adhesive obtained by crosslinking the silicone pressure-sensitive adhesive composition according to any one of claims 1-29.

33. A skin-adhesive article comprising a substrate on at least one of its two surfaces continuously or discontinuously coated with a silicone pressure-sensitive adhesive obtained by crosslinking a medical silicone pressure-sensitive adhesive composition according to any one of claims 1-29.

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