Skin-adhesive item

Abstract

Items that can adhere to the skin for medical or paramedical use are described. Also described, is a skin-adhesive item.

Claims

1. A skin-adhesive item comprising: a support S which is a flexible polyurethane film having a top face S1 and a bottom face S2, at least one tie primer C1 applied to at least one part or to all of the top face S1 of the support S, at least one layer D1 comprising a silicone gel E obtained by crosslinking a crosslinkable silicone composition Y by means of a hydrosilylation reaction, which has been applied to the at least one tie primer C1 facing the support S, and optionally at least one protective layer F comprising of a peel-off protective material and applied to the at least one layer D1, wherein the at least one tie primer C1 comprises a silicone elastomer which is not a silicone gel and which is obtained by crosslinking a silicone composition X comprising: 1) at least one organopolysiloxane A comprising, per molecule, at least two vinyl radicals each bonded to a silicon atom and comprising: (i) at least two siloxy units of formula (A1):
Y.sub.aZ.sub.bSiO.sub.(4(a+b)/2(A1) wherein: Y represents a C2 to C6 alkenyl group, Z represents a monovalent hydrocarbon-based group chosen from alkyl groups having from 1 to 8 carbon atoms inclusive, cycloalkyl groups, and aryl groups, a and b represent integers, a being 1, 2 or 3, b being 0, 1 or 2 and (a+b) being 1, 2 or 3; (ii) and optionally comprising other siloxy units of formula (A2):
Z.sub.cSiO.sub.(4c)/2(A2) wherein: Z has the same meaning as above, and c represents an integer which is 0, 1, 2 or 3; 2) at least one organopolysiloxane B comprising, per molecule, at least three hydrogen atoms each bonded to a silicon atom and comprising: (i) at least three siloxy units of formula (B1):
HZ.sub.bSiO.sub.(3b)/2(B1) wherein: H is a hydrogen atom, Z represents a monovalent hydrocarbon-based group chosen from alkyl groups having from 1 to 8 carbon atoms inclusive, cycloalkyl groups, and aryl groups, b is 0, 1 or 2; (ii) and optionally comprising other siloxy units of formula (B2):
Z.sub.cSiO.sub.(4c)/2(B2) wherein: Z has the same meaning as above, and c represents an integer which is 0, 1, 2, or 3; 3) at least one hydrosilylation catalyst C; 4) at least one hydrosilylation reaction inhibitor D; 5) optionally at least one stabilizing additive K; and 6) optionally at least one silicone resin M which has hydroxyl groups and is free of alkenyl or hydrosilyl SiH groups, and with the proviso that the amounts by weight of the organopolysiloxanes A and B are determined such that the RHalk=nH/tAlk ratio is 1.00RHalk4.5 with: nH=number of moles of hydrogen atom directly bonded to a silicon atom of the organopolysiloxane B, and tAlk=number of moles of alkenyl directly bonded to a silicon atom of the organopolysiloxane A.

2. The skin-adhesive item as claimed in claim 1, wherein the amounts by weight of the organopolysiloxanes A and B are determined such that 1.50RHalk4.0.

3. The skin-adhesive item as claimed in claim 1, wherein the silicone composition X comprises at least two organopolysiloxanes A as claimed in claim 1, and wherein at least one is a silicone resin A1 comprising: (i) at least two siloxy units of formula (A1):
Y.sub.aZ.sub.bSiO.sub.(4(a+b)/2(A1) wherein: Y represents a C.sub.2 to C.sub.6 alkenyl group, Z represents a monovalent hydrocarbon-based group chosen from alkyl groups having from 1 to 8 carbon atoms inclusive, cycloalkyl groups, and aryl groups, a and b represent integers, a being 1, 2 or 3, b being 0, 1 or 2 and (a+b) being 1, 2 or 3; (ii) and other siloxy units of formula (A2):
Z.sub.cSiO.sub.(4c)/2(A2) wherein: Z has the same meaning as above, c represents an integer which is 0, 1, 2 or 3; and with the proviso that at least one siloxy unit (A2) has the formula SiO.sub.4/2.

4. The skin-adhesive item as claimed in claim 3, wherein the silicone resin A1 has the formula MD.sup.ViQ wherein: M is a monovalent siloxyl unit of formula R.sub.3SiO.sub.1/2 D.sup.Vi is a divalent siloxyl unit of formula RXSiO.sub.2/2, and Q is a tetravalent siloxyl unit of formula SiO.sub.4/2, with the radical X corresponding to a vinyl group, and the radical R corresponding to a monovalent hydrocarbon-based group chosen from alkyl groups having from 1 to 8 carbon atoms inclusive, cycloalkyl groups and aryl groups.

5. The skin adhesive item as claimed in claim 3, wherein Y is a vinyl group.

6. The skin adhesive item as claimed in claim 3, wherein when Z is an alkyl group, the alkyl group is a methyl, ethyl, propyl or 3,3,3 trifluoropropyl group.

7. The skin adhesive item as claimed in claim 3, wherein when Z is a cycloalkyl group, the cycloalkyl group is a cyclohexyl, cycloheptyl or cyclooctyl group.

8. The skin adhesive item as claimed in claim 3, wherein when Z is an aryl group, the aryl group is a xylyl, tolyl or phenyl group.

9. The skin adhesive item as claimed in claim 3, wherein a=1.

10. The skin adhesive item as claimed in claim 3, wherein when Z is an alkyl group, the alkyl group is a methyl, ethyl, propyl or 3,3,3 trifluoropropyl group.

11. The skin adhesive item as claimed in claim 3, wherein when Z is a cycloalkyl group, the cycloalkyl group is a cyclohexyl, cycloheptyl or cyclooctyl group.

12. The skin adhesive item as claimed in claim 3, wherein when Z is an aryl group, the aryl group is a xylyl, tolyl or phenyl group.

13. The skin-adhesive item as claimed in claim 1, wherein the support S is a continuous flexible polyurethane film which is permeable to air and impermeable to fluids.

14. The skin-adhesive item as claimed in claim 1, wherein the support S, which is a flexible polyurethane film, comprises, on at least one part of the bottom face S2, a pressure-sensitive adhesive.

15. The skin-adhesive item as claimed in claim 1, wherein the support S is a perforated flexible polyurethane film or a continuous flexible polyurethane film which has a top face S1 and a bottom face S2 and which is impermeable to air and fluids in its parts between the perforations.

16. The skin-adhesive item as claimed in claim 15, wherein the perforations of the support S are circular and have a diameter of from about 50 m to about 10 mm.

17. The skin-adhesive item as claimed in claim 16, wherein the item comprises one or more layers N comprising an absorbent body O, optionally separated by one or more intermediate layers P, placed on the support S on the side of the bottom face S2 of the support S.

18. The skin-adhesive item as claimed in claim 17, wherein the absorbent body O is selected from the group consisting of: a hydrophilic foam, a fabric pad, a hydrogel, a hydrocolloid and an alginate.

19. The skin-adhesive item as claimed in claim 1, wherein: the support S is a perforated flexible polyurethane film, having a top face S1 and a bottom face S2, the at least one tie primer C1 is on the top face S1 of the support S and has been applied discontinuously so as to prevent blocking of the perforations of the support S, and the at least one layer D1 comprising a silicone gel E has been applied discontinuously so as to prevent blocking of the perforations of the support S.

20. The skin-adhesive item as claimed in claim 1, wherein: the at least one tie primer C1 is applied on at least one part or on all of the top face S1 and on a part or on all of the bottom face S2 of the support S, and the at least one layer D1 comprising a silicone gel E obtained by crosslinking a crosslinkable silicone composition Y by means of a hydrosilylation reaction has been applied on said tie primer C1 present on the top face S1 and on the bottom face S2 of said support S.

21. The skin-adhesive item as claimed in claim 1, wherein the thickness of the support S is between about 5 m and about 200 m.

22. The skin-adhesive item as claimed in claim 21, wherein the thickness is between about 10 m and about 75 m.

23. The skin-adhesive item as claimed in claim 1, wherein the item is prepared as a dressing for medical or paramedical use.

24. A process for preparing a skin-adhesive item as described in claim 1, wherein the process comprises: a first step of depositing, on said support S, sufficient amounts of the silicone composition X, and crosslinking the silicone composition X for a sufficient time so as to form the at least one tie primer C1, a second step of depositing, on the at least one tie primer C1, sufficient amounts of the silicone composition Y and crosslinking the silicone composition Y, for a sufficient time so as to form the at least one layer D1.

25. The process as claimed in claim 24, wherein the crosslinking of silicone composition X in the first step is performed at from about 60 C. to about 200 C.

26. The process as claimed in claim 24, wherein the crosslinking of silicone composition Y in the second step is performed at from about 60 C. to about 200 C.

27. A process for preparing a skin-adhesive item of claim 1, wherein the process comprises: successively depositing, on said support S, sufficient amounts: of the silicone composition X, then subsequently the silicone composition Y on the silicone composition X, then crosslinking the silicone compositions X and Y for a sufficient time so as to form the at least one tie primer C1 and the at least one layer D1.

28. The process as claimed in claim 27, wherein, for the silicone composition X, the amounts by weight of the organopolysiloxanes A and B are determined such that the ratio RHalk=1 with RHalk=nH/tAlk and: nH=number of moles of hydrogen atom directly bonded to a silicon atom of the organopolysiloxane B, and tAlk=number of moles of alkenyl directly bonded to a silicon atom of the organopolysiloxane A.

29. The process as claimed in claim 27, wherein the crosslinking of silicone composition X and Y is performed at from about 60 C. to about 200 C.

30. The skin adhesive item as claimed in claim 1, wherein the alkenyl group Y is a vinyl group.

31. The skin adhesive item as claimed in claim 1, wherein when Z is an alkyl group, the alkyl group is a methyl, ethyl, propyl or 3,3,3 trifluoropropyl group.

32. The skin adhesive item as claimed in claim 1, wherein when Z is a cycloalkyl group, the cycloalkyl group is a cyclohexyl, cycloheptyl or cyclooctyl group.

33. The skin adhesive item as claimed in claim 1, wherein when Z is an aryl group, the aryl group is a xylyl, tolyl or phenyl group.

Description

EXAMPLES

(1) The compositions described are in the two-component form. The crosslinking of the primer is carried out after mixing, at 25 C., two parts called Part A and Part B in a 50/50 ratio. The crosslinking of the Silbione HC2 2022 gel in the examples below is carried out after mixing, at 25 C., two parts in a 50/50 ratio.

(2) 1) Starting Materials Used in the Composition of the Primer According to the Invention

(3) POS(A1)=poly(dimethylsiloxy)(methylvinylsiloxy) resin and containing tetravalent siloxyl units (units Q).

(4) POS(A2)=,-(dimethylvinylsiloxy)-substituted polydimethylsiloxane oil of viscosity 600 mPa.Math.s.

(5) POS(B)=,-(dimethylhydrosiloxy)-substituted poly(dimethylsiloxy)(methylhydro-siloxy) oil of viscosity 25 mPa.Math.s and containing 0.7% by weight of group H.

(6) (C)=platinum organometallic complex used as catalyst of the reaction

(7) (D)=inhibitor of the hydrosilylation reaction of -acetylenic alcohol type

(8) (K)=stabilizer of the mixture.

(9) 2) Table 1 Describes the Concentrations of Each of these Constituents in the Part a+Part B Mixtures Tested.

(10) TABLE-US-00001 TABLE 1 Mixture Mixture Mixture Mixture Con- A1 + B1 A2 + B2 A3 + B3 A4 + B4 stituents (comparative) (invention) (invention) (comparative) POS(A1) 52.32 52.13 50.21 43.23 POS(A2) 45.12 45.12 45.12 45.12 POS(B) 2.50 2.69 4.60 11.59 (C) 0.020 0.020 0.020 0.020 (D) 0.020 0.020 0.020 0.020 (K) 0.020 0.020 0.020 0.020 RHalk 0.96 1 1.8 5

(11) 2) Methods for Obtaining the Coatings Tested

(12) Two different methods were monitored in order to test the above compositions as primer for improving the adhesion of the Silbione HC2 2022 gel on a support which is a flexible polyurethane film.

(13) Method for Coating the Primer then the Gel, without Prior Crosslinking of the Primer

(14) Application of the primer at a weight of between 5 and 15 g/m.sup.2 to a support which is a flexible polyurethane film. The primer is applied to the film by means of a coating knife, then application of the Silbione HC2 2022 gel at a weight of 200 g/m.sup.2 by means of a coating knife, and crosslinking of the composite for 30 min at 120 C. in a ventilated oven.
Method for Coating the Primer then the Gel, with Prior Crosslinking of the Primer Application of the primer at a weight of between 5 and 15 g/m.sup.2 to a support which is a flexible polyurethane film. The primer is applied to the film by means of a coating knife, then crosslinking of the primer for 5 min at 150 C. in a ventilated oven, then application of the Silbione HC2 2022 gel at a weight of 200 g/m.sup.2 by means of a coating knife, and crosslinking of the composite for 30 min at 120 C. in a ventilated oven.

(15) 3) Tests Carried Out on the Coatings

(16) The two key properties tested in order to evaluate the efficiency of the primer are the adhesion of the primer or of the gel to the flexible polyurethane support and the adhesive capacity of the gel on the skin (tack). Indeed, when the adhesion of a silicone gel on a flexible polyurethane film is improved by the use of a primer, it is important to be sure that the adhesive capacity of the gel on the skin (tack) is preserved and that the adhesion of a medical device to the skin will not be modified by the use of a primer.

(17) Evaluation of the Adhesive Capacity of the Silicone Gel on the Skin

(18) The PROBE TACK Device (PT-1000) is the instrument used to evaluate the adhesive capacity of the gel coated. The test is carried out according to standard ASTM D2979 with the following test parameters: surface area of contact with the adhesive: 0.2 cm.sup.2, contact time with the adhesive: 1 s, contact pressure: 20 gf, speed of separation of the punch from the adhesive: 10 mm/s.

(19) The energy for detachment from the substrate is expressed in mJ/cm.sup.2.

(20) Evaluation of the Adhesion of the Silicone Gel to the Support which is a Flexible Polyurethane Film

(21) The adhesion of the silicone gel to the support which is a flexible polyurethane film consists of a qualitative evaluation of the resistance of the gel during rub-off with a finger. The gel will be considered to be more adherent to the polyurethane film if the number of rub-offs is higher before observing delamination of the gel from its substrate.

(22) 4) Tables 2 and 3 Present the Application Properties Obtained as a Function of the Coating Method Used a) According to the method of coating the primer and then the gel, without prior crosslinking of the primer:

(23) TABLE-US-00002 TABLE 2 With primer Mixture Mixture Without Mixture A1 + B1 A2 + B2 A3 + B3 Mixture A4 + B4 primer (comparative) (invention) (invention) (comparative) Probe Tack 20 20 21 14 11 (mJ/cm.sup.2) Adhesion of the 5 5 >30 >30 >30 gel to polyurethane film (number of rub- offs with a finger)

(24) The gel coated onto primer according to this first process has: a) good adhesion on a support which is a flexible polyurethane film, and b) satisfactory adhesion to the skin,

(25) insofar as the RHalk ratio of the primer is greater than or equal to 1 and less than or equal to 4.5.

(26) The composition of the primer of which the RHalk ratio is equal to 1 (mixture A2+B2) provides a very good balance of properties (improvement of the adhesion of the silicone gel to the flexible polyurethane support, preservation of the adhesive capacity and the tack of the gel on the skin). b) According to the method of coating the primer and then the gel, with prior crosslinking of the primer:

(27) TABLE-US-00003 TABLE 3 With primer Mixture Mixture Without Mixture A1 + B1 A2 + B2 A3 + B3 Mixture A4 + B4 primer (comparative) (invention) (invention) (comparative) Probe Tack 20 19 19 21 11 (mJ/cm.sup.2) Adhesion of the 5 5 20 >30 >30 gel to polyurethane film (number of rub- offs with a finger)

(28) The gel coated onto primer according to this second process has: a) good adhesion on a support which is a flexible polyurethane film, and b) satisfactory adhesion to the skin,

(29) insofar as the RHalk ratio of the primer is greater than or equal to 1 and less than or equal to 4.5.

(30) The composition of the primer of which the RHalk ratio is equal to 1.8 (mixture A3+B3) provides a very good balance of properties (improvement of the adhesion of the silicone gel to the flexible polyurethane support, preservation of the adhesive capacity, the tack and of the gel on the skin).