Reinforced adhesive film, in particular for applications in the medical field, and method for manufacturing such a film.

Abstract

- Reinforced adhesive film, in particular for applications in the medical field, and method for manufacturing such a film. - The method for manufacturing a reinforced adhesive film (1) comprises a single main coating step, implemented by a coating device, consisting, in a single pass, of completely embedding a frame (2) formed of a non-woven fabric (3) in a pressure-sensitive adhesive formulation (4) so that the adhesive formulation (4) completely covers both faces (2A, 2B) of the frame (2), which makes it possible to quickly obtain, using a simple manufacturing method, a reinforced adhesive film (1) having advantageous properties in particular in terms of adhesion, hold, conformability and breathability. Figure for the abstract: Fig. 1

Description

Title of the invention: Reinforced adhesive film, in particular for applications in the medical field, and method for manufacturing such a film. Technical field

[0001] The present invention relates to a reinforced adhesive film, in particular for applications in the medical field, as well as to a method for manufacturing such a film. State of the art

[0002] The reinforced adhesive film can be used in different fields, in particular in the industrial field and in particular in the construction sector, as well as in the medical field, in particular for the adhesion of any type of operating field.

[0003] This adhesive film, when used in an operating room in a hospital environment, can be applied by surgeons during operations, for bonding either on an operating table or directly on a patient.

[0004] Currently, there are double-sided adhesives, incorporating adhesive formulations, which are used for such applications.

[0005] Alone, such adhesive formulations have several drawbacks. In particular: - it is necessary to make them more consistent, solid and resistant, for use in particular in the medical field, which tends to reduce and limit the extent of their properties; and - when cut for use, they tend to pollute cutting tools.

[0006] On the other hand, double-sided adhesives are resistant during cutting and use processes, but have the disadvantage of being non-permeable to water, which can cause detachments when applied to different substrates.

[0007] Furthermore, the presence of a central frame stiffens the assembly and reduces the adhesive performance of the complex.

[0008] Also, there is an interest and a need to be able to have a reinforced adhesive film making it possible to overcome these drawbacks. Statement of the invention

[0009] The object of the present invention is to propose a reinforced adhesive film, capable of being used in particular in the aforementioned applications and of meeting this need.

[0010] According to the invention, said reinforced adhesive film comprises a weft formed of a non-woven fabric, which is completely embedded in a pressure-sensitive adhesive formulation such that the adhesive formulation (completely encompasses the weft and) covers completely both sides of the frame.

[0011] Thus, an adhesive film is obtained whose hold and resistance are reinforced, thanks to the integration of the weft (formed from the non-woven). This also ensures that the initial properties and performance of the adhesive film thus reinforced are not deteriorated over time, in particular when it is subjected to various stages of transformation as is generally the case.

[0012] The addition of the weft in the adhesive formulation makes it possible, in addition to reinforcing the hold of the adhesive film, to improve its stability during storage of the finished product comprising this adhesive film as well as to facilitate the cutting of the film (and this without polluting the cutting tools).

[0013] In addition, the non-occlusive nature of said adhesive film is also an advantage regarding resistance to humidity on different surfaces.

[0014] Thanks to its advantageous properties specified below, this reinforced adhesive film is particularly well suited for use in the medical field, in particular in an operating theatre to be applied by surgeons during operations, by gluing either on an operating table or directly on a patient. This reinforced adhesive film will be able to advantageously replace the usual double-sided adhesives, making it possible to overcome their drawbacks specified above.

[0015] In a preferred embodiment, the reinforced adhesive film has at least some of the following characteristics: - a water vapor transmission rate greater than 400 g / m2 / 24h, illustrating its breathability properties; - an adhesive power on glass greater than 300 N / m; and - increased conformability (compared in particular to double-sided adhesives), as specified below.

[0016] These characteristics allow the film to obtain the aforementioned properties.

[0017] In a first embodiment, the adhesive formulation is an acrylic polymer crosslinkable under ultraviolet rays, with butyl acrylate and acrylic acid as base monomers.

[0018] Preferably, this acrylic polymer is formulated with a tackifying resin of hydrocarbon nature.

[0019] Furthermore, in a second embodiment, the adhesive formulation is a solvent-borne acrylic polymer, with 2-ethylhexyl acrylate as the base monomer.

[0020] Furthermore, in a third embodiment, the adhesive formulation is an elastomer of the styrene-isoprene-styrene type or of the styrene-butadiene-styrene type.

[0021] Preferably, the elastomer is formulated with at least one of the following types of components: resin, plasticizer, antioxidant.

[0022] Furthermore, advantageously, the non-woven fabric forming the weft is made of polyester, and has at least some of the following characteristics: - a weight between 3 and 8 g / m; - a thickness between 0.03 and 0.07 mm; - a breaking strength of between 20 and 30 N / 5cm; - an elongation at break which is between 4 and 8%; - a water vapor transmission rate that is greater than 10,000 g / m2 / 24h.

[0023] Preferably, the fibers of the nonwoven forming the weft are oriented substantially in a single direction in particular so as to increase the strength of the adhesive film.

[0024] Furthermore, in a preferred embodiment, the reinforced adhesive film comprises a protective film which is silicone-coated on both of its faces and which supports on one of its silicone-coated faces the assembly formed from the adhesive formulation in which the frame is embedded.

[0025] The present invention also relates to a method of manufacturing a reinforced adhesive film.

[0026] According to the invention, said method comprises a single main coating step, implemented by a coating device, consisting, during a single pass, of completely embedding a weft formed from a non-woven fabric in a pressure-sensitive adhesive formulation so that the adhesive formulation (completely encompasses the weft and) completely covers both faces of the weft.

[0027] Thus, thanks to the invention, the reinforced adhesive film (which has the aforementioned advantageous characteristics) is obtained in a single pass during which the non-woven fabric is completely immersed in the adhesive formulation. This makes it possible to obtain a particularly simple manufacturing process and rapid manufacturing, compared to conventional processes which comprise at least two passes (namely a first pass for depositing an adhesive on a first face of a support and a second pass for depositing an adhesive on the second face of the support).

[0028] Advantageously, the non-woven fabric of the weft has suitable characteristics allowing the adhesive formulation to pass through it and to be on both sides of the non-woven fabric. These characteristics are preferably adapted to the characteristics of the adhesive formulation.

[0029] The method also comprises an auxiliary coating step which consists of depositing the adhesive formulation on a protective film, and which: - in a first embodiment, is implemented prior to the main coating step; and - in a second embodiment, is implemented at the same time as the main coating step.

[0030] Advantageously, the adhesive formulation used is either hot-melt or solvent-based. Brief description of the figures

[0031] Other advantages and characteristics will emerge more clearly from the following description of several embodiments, given as non-limiting examples, of a reinforced adhesive film in accordance with the invention and its manufacturing method, with particular reference to the appended figures. In these figures, identical references designate similar elements.

[0032] [Fig. 1] is a partial schematic view, in section, of a reinforced adhesive film, in accordance with one embodiment of the invention.

[0033] [Fig.2] is a schematic view of a first embodiment of a device for manufacturing a reinforced adhesive film.

[0034] [Fig. 3] is a schematic view of a second embodiment of a device for manufacturing a reinforced adhesive film.

[0035] [Fig.4] is a schematic view of a variant of the second embodiment of [Fig.3]. Detailed description

[0036] The film 1 used to illustrate the invention and partially represented according to a particular embodiment in [Fig. 1] is a reinforced adhesive film, as specified below.

[0037] As shown in [Fig.l], the film 1 comprises a frame 2 formed from a non-woven fabric 3.

[0038] This frame 2 is completely embedded in a pressure-sensitive adhesive formulation 4 such that the adhesive formulation 4 completely encompasses the frame 2 and completely covers the two faces 2A and 2B of the frame 2. Thus, two adhesive layers 5 and 6 are formed on either side of the frame 2 made of non-woven fabric 3. The adhesive layer 5 is formed on the face 2A of the frame 2 and the adhesive layer 6 is formed on the face 2B of the frame 2.

[0039] As specified below, the adhesive formulation 4 used to manufacture the film 1 is either hot melt or solvent phase. The adhesive formulation 4 is represented very schematically by small black dots in Figures 1, 3 and 4.

[0040] The film 1 also comprises a protective film 7, on one of the faces of the assembly 8 formed from the adhesive formulation 4 in which the frame 2 is embedded.

[0041] In the example of [Fig.l], the protective film 7 is in contact by a face 7A with a face 6B of the adhesive layer 6 (which is opposite the face 6A in contact with the face 2B of the frame 2). The adhesive layer 5 comprises two faces 5A and 5B, the face 5B of which is in contact with the face 2A of the frame 2.

[0042] Preferably, the protective film 7 is a glassine paper, siliconized on its two faces 7A and 7B. This makes it possible to wind the film 1 on itself, the face 5A of the film 1 coming into contact with the face 7B (siliconized) of the protective film 7 during winding.

[0043] In a preferred embodiment, the reinforced adhesive film 1 has at least some of the following characteristics: - an adhesive power of 1 min at 90° on glass, greater than 300 N / m on the visible side and on the hidden side, illustrating its adhesion properties; - a T-shaped decomplexing force between the protective film 7 and the adhesive layer 6 of between 10 and 60 cN / 5cm; - a moisture vapor transmission rate (MVTR), namely the water permeation rate through a membrane, measured (according to standard NF EN 13726-2) in mass per unit area per unit time, in this case in g / m2 / 24h, which is greater than 400 g / m2 / 24h (hidden side and visible side), illustrating its breathability properties; - a T-shaped decomplexing force on the operating field (film) after 24 hours, greater than 500 cN / 5cm; - a T-shaped decomplexing force on the operating field (non-woven) after 24 hours, greater than 500 cN / 5cm.

[0044] For the purposes of the present invention, the ranges of values ​​presented as "between x and y" include the bounds x and y, the integers between these bounds, as well as all other real numbers between these bounds.

[0045] Thus, an adhesive film 1 is obtained whose hold and resistance are reinforced, thanks to the integration of the weft 2 (formed from the non-woven 3). In addition, the initial properties and performances of the adhesive film 1 thus reinforced are not deteriorated over time, in particular when it is subjected to various transformation stages as is generally the case. The addition of the weft 2 in the adhesive formulation 4 also makes it possible to improve its stability during storage of the finished product comprising this film 1, and to facilitate the cutting of the film 1 (and this without polluting the cutting tools used for this purpose).

[0046] In the context of the present invention, the adhesive formulation 4 used to manufacture the film 1 can be produced in different ways.

[0047] In a first embodiment, the adhesive formulation 4 corresponds to an acrylic polymer crosslinkable under ultraviolet (UV) rays, with butyl acrylate (BA) and acrylic acid (AA) as base monomers.

[0048] Preferably, this acrylic polymer is formulated with a tackifying resin of hydrocarbon nature, in order to provide particular adhesiveness to the film 1 (if necessary or useful).

[0049] Further, in a second embodiment, the adhesive formulation 4 corresponds to a solvent-based acrylic polymer, non-crosslinkable under ultraviolet rays, based on EHA monomer (2-ethylhexyl acrylate).

[0050] Furthermore, in a third embodiment, the adhesive formulation 4 corresponds to an elastomer of the styrene-isoprene-styrene (SIS) or styrene-butadiene-styrene (SBS) type.

[0051] Preferably, this elastomer is formulated with at least one of the following types of components: resin, plasticizer, antioxidant, in order to provide the desired properties to the film 1.

[0052] It will be noted that the choice concerning the chemical nature (acrylic or elastomer) of the adhesive formulation 4 may depend on the substrate(s) of the intended application and the setting time of the adhesive formulation 4.

[0053] By way of illustration, the table below highlights the main characteristics of the adhesive formulation 4 for four different examples named FAI to FA4, which are likely to be used to produce the film 1. Commercial reference e FAI: HM- R2292 FA2: HM- R2519A FA3: AS-333 FA4: AS-1959 Technology hot melt hot melt solvent phase solvent phase Composition of monomers constituting acrylic (%) 94% butyl acrylate 4% acrylic acid 2% ethyl acrylate 89.3% butyl acrylate 3.8% acrylic acid 1.9% ethyl acrylate 5% aromatic tackifying resin 2-ethylhexyl acrylate vinyl acetate acrylic acid 2-ethylhexyl acrylate vinyl acetate acrylic acid Brookfield Viscosity (mPa.s) 130°C: speed 1: 75,000 speed 2.5: 71,000 speed 5: 66,000 130°C: speed 1: 54 750 speed 2.5: 47 100 speed 5: 43 550 25°C: 3200 - 5800 25°C: 4000 - 10000

[0054] This table presents for the four examples FAI to FA4 considered of formulation adhesive 4: - their commercial reference; - technology (hot melt or solvent phase); - the composition of the monomers constituting the acrylic, in percentage (%); and - the “Brookfield” viscosity in mPa.s (measured according to standard NF EN ISO 2555).

[0055] Furthermore, in a preferred embodiment, the non-woven fabric 3 forming the weft 2 is very airy, in particular to allow the passage of the adhesive formulation 4. Preferably, the non-woven fabric 3 is composed of polyester fibers.

[0056] In a preferred embodiment, the fibers 11 of the nonwoven 3 are of the monodirectional type and are therefore oriented in a single direction. This makes it possible in particular to increase the strength of the film 1.

[0057] In comparison with nonwovens using “spunbond” technology, thinner thicknesses can thus be obtained for nonwoven 3 for an identical weight.

[0058] In a preferred embodiment, the nonwoven 3 has at least some of the following characteristics: - a weight between 3 and 8 g / m2 (FTM12); - a thickness between 0.03 and 0.07 mm (measured according to standard NF EN ISO 534); - a breaking strength of between 20 and 30 N / 5cm (measured according to standard NF EN 29073-3) in the direction of the machine (MD for “machine direction” in English); - an elongation at break which is between 4 and 8% (measured according to standard NF EN 29073-3); - a water vapor transmission rate (MVTR for “Moisture Vapor Transmission Rate” in English), namely the water permeation rate through a membrane, measured (according to standard NF EN 13726-2) in mass per unit of surface per unit of time, in this case in g / m2 / 24h, which is greater than 10,000 g / m2 / 24h.

[0059] The film 1, as described above, can be obtained using a manufacturing method specified below. This manufacturing method, preferably in large width, comprises, in particular, a main coating step in a single pass.

[0060] This (single) main coating step which is implemented by a coating device, consists, during a single pass, of completely embedding a frame 2 formed of a non-woven fabric 3 in a pressure-sensitive adhesive formulation 4 so that the adhesive formulation 4 completely encompasses the frame 2 and completely covers the two faces 2A and 2B of the frame 2 ([Fig.l]).

[0061] Thus, the film (reinforced adhesive) 1 which has the aforementioned advantageous characteristics, is obtained during a single pass (at the coating device) at the end of which the non-woven 3 is completely immersed in the adhesive formulation 4.

[0062] To do this, the nonwoven 3 comprises appropriate characteristics and is in particular very aerated to allow the adhesive formulation 4 to pass through it and to be present on both sides of the nonwoven 3, for example when the nonwoven 3 passes under a coating nozzle (bringing the adhesive formulation 4) of the coating device. These characteristics of the nonwoven 3 of the weft 2 (such as being aerated) can be adapted to the characteristics (for example the viscosity) of the adhesive formulation 4 to allow the adhesive formulation 4 to be present on both sides of the weft 2 and to completely envelop it.

[0063] The manufacturing method also comprises a so-called auxiliary coating step, consisting of depositing the adhesive formulation 4 on the protective film 7. The frame 2 can be embedded in the adhesive formulation 4 at the same time as the latter is deposited on the protective film 7 or after the adhesive formulation 4 has been deposited on the protective film 7. Thus, in a first implementation corresponding to the embodiments of FIGS. 2 and 4 described below, the auxiliary coating step is implemented at the same time as the main coating step, and in a second implementation corresponding to the embodiment of [Fig. 3], the auxiliary coating step (deposition of the adhesive formulation 4 on the protective film 7) is implemented prior to the main coating step (integration of the frame 2 in the adhesive formulation 4).

[0064] In the context of the present invention, the manufacturing method, and in particular its main coating step, can be implemented using different coating devices such as, for example, those described below, by way of illustration, with reference to Figures 2 to 4.

[0065] In a first embodiment shown in [Fig. 2], the manufacturing method uses a manufacturing device 9A which comprises a coating device 10A. The manufacturing device 9A is configured to implement a large-width (1500 mm) hotmelt process.

[0066] In this first embodiment, the manufacturing device 9A further comprises a supply system 12A for protective film 7, provided in particular with a reel 13 of protective film 7, and a supply system 14A for non-woven fabric 3, provided in particular with a reel 15 of non-woven fabric 3.

[0067] The non-woven fabric 3 and the protective film 7 are brought, by these supply systems 12A and 14A, in the directions illustrated respectively by arrows 16A and 17A, to the coating device 10A. The coating device 10A is provided with at least one coating nozzle 23A and is supplied, in the usual manner, with adhesive formulation 4. The protective film 7 which serves as a support for the hot-melt adhesive formulation 4 in which the weft 2 of non-woven fabric 3 is embedded (also brought to this level), passes under the coating nozzle(s) 16A (to receive the adhesive formulation 4 as illustrated by an arrow 19A) so that, in connection with the characteristics of the nonwoven 3, the hot-melt adhesive formulation 4 is distributed on both sides of the weft 2 in nonwoven 3.

[0068] The assembly (formed from this non-woven fabric 3 which is embedded in the adhesive formulation 4 deposited on the protective film 7) is brought, in the direction illustrated by arrows 18A, through a drying system 20 (or drying tunnel or oven(s)), then is wound at a winding station 21, downstream of the drying system 20. At this winding station 21, the reinforced adhesive film 1 which has just been manufactured is wound onto a reel.

[0069] In an alternative embodiment (not shown), the drying system 20 is replaced, in the usual manner, by UV lamps, in particular when using hotmelt acrylics crosslinkable under ultraviolet (UV) rays for the adhesive formulation 4.

[0070] In a second embodiment shown in [Fig. 3], the manufacturing method uses a manufacturing device 9B comprising a coating device 10B configured to implement solvent-phase manufacturing, in large width (1500 mm).

[0071] In this second embodiment, the manufacturing device 9B further comprises a supply system 12B for protective film 7 and a supply system 14B for non-woven fabric 3.

[0072] The nonwoven 3 and the protective film 7 are brought, by these supply systems 12B and 14B, in the directions illustrated respectively by arrows 16B and 17B, to the coating device 10B. The coating device 10B is provided with at least one supply system 23B which supplies, in the usual manner, the adhesive formulation 4.

[0073] The coating device 10B is configured to deposit the adhesive formulation 4 in solvent phase on the protective film 7, as illustrated by an arrow 19B, upstream of a doctor blade 22B of the coating device 10B, in the direction of movement (illustrated by an arrow 18B) of the film 1.

[0074] The non-woven fabric 3 (supplied by the non-woven fabric supply system 14B) is, for its part, integrated downstream of the doctor blade 22B, in the adhesive formulation 4 previously deposited on the protective film 7.

[0075] Downstream of this integration, the assembly (formed from this non-woven fabric 3 which is embedded in the adhesive formulation 4 deposited on the protective film 7) is subjected to usual treatments, in particular drying and winding, using usual devices (not shown).

[0076] Furthermore, in a third embodiment shown in [Fig.4] which is a variant of the second embodiment of [Fig.3], the manufacturing method uses a manufacturing device 9C comprising a coating device 10C. Unlike the coating device 10B of the second embodiment, the coating device 10C is configured so that the non-woven fabric 3 is integrated into the adhesive formulation 4 deposited on the protective film 7, upstream of a doctor blade 22C in the direction of movement (illustrated by an arrow 18C) of the film 1.

[0077] The feed system 14C is therefore arranged upstream of the doctor blade 22C. Most of the other elements of the manufacturing device 9C are identical or similar to those of the manufacturing device 9B. In particular, the nonwoven 3 and the protective film 7 are brought, by feed systems 12C and 14C, in the direction illustrated respectively by arrows 16C and 17C, to the coating device 10C provided with at least one feed system 23C providing the adhesive formulation 4 (arrow 19C).

[0078] Regardless of the coating device 10A, 10B and 10C and the manufacturing device 9A, 9B and 9C used, the manufacturing method implemented uses a non-woven fabric 3, an adhesive formulation 4 and a protective film 7, such as those described above.

[0079] In particular, it takes into account the characteristics (such as thickness, weight, etc.) specified above of the non-woven fabric 3, the characteristics specified above of the adhesive formulation 4 and the characteristics specified above of the protective film 7.

[0080] The manufacturing devices 9A, 9B and 9C described above make it possible to carry out a coating, in large width, of an adhesive formulation 4 on a non-woven fabric 3 in a single pass. This provides a simple and rapid manufacturing method, compared to conventional manufacturing methods which comprise at least two passes (namely a first pass for depositing an adhesive on a first face of a support and a second pass for depositing an adhesive on the second face of the support).

[0081] In addition, the reinforced adhesive film 1, thus obtained, has the particularly advantageous characteristics specified above.

[0082] The table below presents a comparison between an example F1 of film 1 (obtained by a process in accordance with a particular embodiment of the invention) and a known conventional double-sided adhesive (P7592) and makes it possible to highlight the advantageous characteristics of film 1. Fl P7592 Construction Adhesive HM-R 2519A, 60 g / m2 visible side: HMR-2292, 60g / m2 hidden side: HMR-2292, 40g / m2 Monodirectional non-woven weave none Backing none PET film, 17g / m2 Protective film silicone paper 2F differentiated silicone paper 2F undifferentiated Weight g / m2 60 100 PA 90° on glass 1 min - Visible side - cN / cm 467 750 PA 90° on glass 1 min - Hidden side - cN / cm 565 825 MVTR steam contact (g / m2 / 24h) 870 45

[0083] This table shows for the two products considered: - the characteristics of the adhesive (or adhesive formulation) used; - the presence or absence of a frame and a support; - the characteristics of the protective film used; - the weight in g / m2; - the PA 90° adhesive power on glass 1 minute, respectively for the visible face and the hidden face, in cN / cm; and - the water vapor transmission rate (MTVR) in g / m2 / 24h.

[0084] This table makes it possible in particular to highlight the following advantageous characteristics of film 1: - a water vapor transmission rate greater than 400 g / m2 / 24h, illustrating these breathability properties; - an adhesive power greater than 300 N / m; and - superior conformability to double-sided adhesives.

[0085] The improved conformability of film 1 can be demonstrated by a mechanical hysteresis test and a test illustrating flexibility.

[0086] Concerning the hysteresis test, 20% deformation measurements were carried out, both on film 1 and on the aforementioned usual double-sided adhesive (P7592), for test pieces 15 mm wide and 10 cm long.

[0087] The table below presents a comparison between example F1 of film 1 (obtained by a process in accordance with a particular embodiment of the invention) and the usual known double-sided adhesive (P7592), showing the values ​​of different parameters, and it makes it possible to highlight the advantageous characteristics of film 1 concerning conformability. Hysteresis force (N / cm) Remanence (%) Starting slope (N / cm / %) Fl 6.4 14.9 0.6 P7592 13.5 15.4 4.5

[0088] This table shows for the two products considered: - the hysteresis force, in N / cm; - the remanence, in %; and - the slope at the start of the hysteresis curve, in N / cm / %.

[0089] It is noted that the difference between the measurements in terms of remanence is small, but the double-sided adhesive is, however, more resistant to deformation than film 1.

[0090] As for the starting slopes of the hysteresis curves (and therefore the Young's moduli), they show a difference in behavior between the two products analyzed. The double-sided adhesive is much more rigid than film 1.

[0091] Furthermore, for the loop flexibility test, specimens 20cm long and 2cm wide were used. For each of the two products, the corresponding specimen was held by its free ends, brought into contact and arranged vertically upwards, so as to form a loop.

[0092] In this test, we observe a different loop shape for the two products, with a maximum loop width: - 2.5 cm for film 1; and - 4 cm for the usual double-sided adhesive (P7592).

[0093] This test makes it possible to demonstrate the flexibility of film 1 (reinforced by weft 2) compared to the double-sided adhesive (in polyester).

[0094] The improved conformability of film 1, compared to a usual double-sided adhesive, was thus demonstrated by these two tests, the mechanical hysteresis test and the flexibility test.

[0095] The film 1, as described above, which has advantageous adhesive and cohesive properties, is particularly well suited to use in an operating theatre, and can in particular be applied by surgeons during operations in a hospital environment, for bonding either on an operating table or directly on a patient.

[0096] The film 1, as described above, can be used in many other applications, in particular (but not exclusively) in the medical sector. More generally, the film 1 can be used in all applications in which its advantageous characteristics (and in particular its reinforced adhesive properties) are sought.

[0097] It can in particular be used in the industrial field, and in particular in the construction sector, in which one can in particular take advantage of its breathability properties.

[0098] It is obvious that the examples presented above are only particular illustrations, in no way limiting as to the fields of application of the present invention. In addition, features of some of these different examples can be combined with each other if appropriate, without departing from the scope of the present invention.

Claims

Claims

1. Reinforced adhesive film, in particular for the medical field, characterized in that it comprises a frame (2) formed of a non-woven fabric (3), which is completely embedded in a pressure-sensitive adhesive formulation (4) such that the adhesive formulation (4) completely covers both faces (2A, 2B) of the frame (2).

2. Film according to claim 1, characterized in that said reinforced adhesive film (1) has at least some of the following characteristics: - a water vapor transmission rate greater than 400 g / m2 / 24h; - an adhesive power on glass greater than 300 N / m; and - increased conformability.

3. Film according to one of claims 1 and 2, characterized in that the adhesive formulation (4) is an acrylic polymer crosslinkable under ultraviolet rays, with butyl acrylate and acrylic acid as basic monomers.

4. 4. Film according to claim 3, characterized in that the acrylic polymer is formulated with a tackifying resin of hydrocarbon nature.

5. Film according to one of claims 1 and 2, characterized in that the adhesive formulation (4) is an acrylic polymer in solvent phase, with 2-ethylhexyl acrylate as base monomer.

6. 6. Film according to one of claims 1 and 2, characterized in that the adhesive formulation (4) is an elastomer of the styrene-isoprene-styrene type or of the styrene-butadiene-styrene type.

7. 7. Film according to claim 6, characterized in that the elastomer is formulated with at least one of the following types of components: resin, plasticizer, antioxidant.

8. 8. Film according to any one of the preceding claims, characterized in that the non-woven fabric (3) forming the weft (2) is made of polyester, and has at least some of the following characteristics: - a weight between 3 and 8 g / m; - a thickness between 0.03 and 0.07 mm; - a breaking strength between 20 and 30 N / 5 cm; - an elongation at break which is between 4 and 8%; - a water vapor transmission rate which is greater than 10,000 g / m2 / 24h.

9. 9. Film according to any one of the preceding claims, characterized in that the fibers (11) of the non-woven fabric (3) forming the weft (2) are oriented substantially in one and the same direction.

10. 10. Film according to any one of the preceding claims, characterized in that it comprises a protective film (7) which is silicone-coated on its two faces (7A, 7B) and which supports, on one (7A) of its silicone-coated faces (7A, 7B), the assembly (8) formed from the adhesive formulation (4) in which the frame (2) is embedded.

11. 11. Method for manufacturing a reinforced adhesive film, characterized in that it comprises a single main coating step, implemented by a coating device (10A, 10B, 10C), consisting, during a single pass, of completely embedding a frame (2) formed from a non-woven fabric (3) in a pressure-sensitive adhesive formulation (4) so ​​that the adhesive formulation (4) completely covers the two faces (2A, 2B) of the frame (2).

12. 12. Method according to claim 11, characterized in that it comprises an auxiliary coating step consisting of depositing the adhesive formulation (4) on a protective film (7), which is carried out prior to the main coating step.

13. 13. Method according to claim 11, characterized in that it comprises an auxiliary coating step consisting of depositing the adhesive formulation (4) on a protective film (7), which is carried out at the same time as the main coating step.

14. 14. Method according to one of claims 11 to 13, characterized in that the adhesive formulation (4) used is either hot-melt or in solvent phase.

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