Method for transferring an electronic circuit comprising an encapsulated transducer, transferring device and method for manufacturing such a device and composite obtained

Abstract

The invention relates to a device (1) designed to transfer an electronic circuit (6) from a mother substrate (2) to a child substrate, comprising a) a mother substrate (2) of area SM, b) a layer L1 (3) of a polymer composition c1 of area SL1 arranged on all or part of the mother substrate (2), and c) at least one electronic circuit (6) of area ST comprising at least one transducer (60) and optionally one or more electrically conductive traces, the at least one electronic circuit is arranged on all or a part of the layer L1 (3) and adheres to the layer L1, the transducer (6) comprising at least two electrically conductive electrodes separated by an electroactive layer of a polymer composition wherein the layer L1 (3) is removably secured to the mother substrate (2).

Description

TECHNICAL FIELD

[0001] The present invention relates to a method for transferring an electronic circuit comprising or consisting of at least one transducer from a mother substrate to a daughter substrate, said transducer being based on an electroactive polymer composition. The present invention also relates to a device for carrying out the transfer, and to a composite obtained after the transfer. The present invention also relates to a method for manufacturing a device for carrying out the transfer.

[0002] The present invention notably makes it possible to fix a transducer or an electronic circuit comprising at least one transducer to any type of substrate (daughter substrate). This is particularly beneficial for fixing a transducer or an electronic circuit comprising at least one transducer to a deformable or rough substrate and / or to a large and immovable substrate (for example, a substrate forming part of an existing non-instrumented infrastructure). BACKGROUND

[0003] A material is said to be "electroactive" if it exhibits a response (deformation, temperature change, etc.) during the application of an electric field and / or if a stress (mechanical, thermal, etc.) induces an electrical response within the material.

[0004] A transducer is a device that can convert a physical quantity into an electrical signal or vice versa. An electroactive transducer is generally formed from a composition of electroactive material arranged between two electrodes.

[0005] The demand for electroactive transducers for various applications using various substrates is constantly increasing. In particular, there is a need to be able to fix one or more transducers or a circuit comprising a transducer to various surfaces, in particular to stretchable surfaces or surfaces having a certain roughness. These substrates notably include human skin, leather and textiles, and the applications include measuring heart rate or respiration. There is also a particular need to be able to fix one or more transducers or a circuit comprising the transducer to surfaces of existing non-instrumented infrastructures. These substrates notably include composites, and the applications include measuring the structural condition or deformation of reservoirs or reactors, wind turbine blades or batteries.

[0006] The method of printing an organic electronic element directly on an uneven surface is very difficult, if not impossible to achieve, because the lack of a smooth surface and / or the presence of a deformable surface are sources of printing defects and lead to the production of transducers of poor quality or, worse, defective. Various attempts have been made to make it possible to obtain transducers on such surfaces. WO2022 / 200934 discloses a composite formed by stacking a leather substrate, a haptic device comprising a piezoelectric polymer manufactured by screen printing and a polymer film covering it. The patent application describes a method of manufacturing a composite comprising a step of hot pressing the polymer film onto the haptic device by applying a pressure of 3 to 4 bars for at least 30 seconds at a temperature of 130 to 160°C. When the piezoelectric polymer has to be polarized, the use of these high temperatures close to or above the Curie temperature of the piezoelectric polymer for the pressing step is not conducive to satisfactorily preserving the piezoelectricity. In addition, this hot pressing step requires the use of a substrate capable of withstanding temperatures greater than 100°C, or if not the case, leads to the destruction of the substrate, which reduces the possible applications.

[0007] There is therefore a need to provide a device that makes it possible to fix an electronic circuit comprising or consisting of at least one transducer to any type of substrate (sub-substrate in the invention). The electronic circuit must be able to be fixed to any type of substrate without damaging the substrate and without any deterioration of the electroactive properties of the transducer. SUMMARY

[0008] One object of the invention is to provide a device suitable for transferring an electronic surface from a mother substrate to a sub-substrate, which makes it possible to fix the electronic circuit to any type of substrate, where the transfer must be able to be carried out without damaging the substrate and without degrading the electroactive properties of the transducer.

[0009] According to at least some embodiments, another object of the invention is to propose a device in which the electronic circuit to be transferred and / or the transferred electronic circuit is protected from the external environment, for example from the attacks by air, humidity, or other chemical attacks, for example attacks by corrosive products or sweat, or attacks by scratching.

[0010] According to at least some embodiments, another object of the invention is to propose a device that is easy to manufacture.

[0011] According to at least some embodiments, another object of the invention is to propose a device that allows the electronic circuit to be simply and effectively transferred from the mother substrate to the sub-substrate.

[0012] Other objects of the present invention in connection with the object of providing the device are to provide a composite formed of an electronic circuit fixed to a sub- substrate, to provide a method for manufacturing the device, and to provide a method for transferring the electronic circuit to a sub- substrate.

[0013] According to a first aspect, the present invention relates to a device (1) suitable for transferring an electronic circuit (6) from a mother substrate (2) to a sub- substrate, comprising a) a mother substrate (2) having a surface S M , b) a layer L1 (3) of a polymeric composition c1 having a surface S L1 , which is arranged on all or a part of the mother substrate (2), and c) at least one electronic circuit (6) having a surface S T , said at least one electronic circuit (6) comprising at least one transducer (60) and optionally one or more electrically conductive tracks (71, 72), said at least one electronic circuit being arranged on all or a part of the layer L1 (3) and adhering to the layer L1, said transducer (6) comprising at least two electrically conductive electrodes (61, 62; 66, 67) separated by one or more layers (63; 68) of an electroactive polymeric composition.

[0014] The layer L1 (3) is detachably fixed to the mother substrate (2).

[0015] The device (1) optionally comprises a layer L2 (4) of a polymeric composition c2, which is arranged on all or a part of the free surface of the stack formed by the layer L1 (3) and the at least one electronic circuit (6) and adheres to all or a part of the free surface of the stack formed by the layer L1 (3) and the at least one electronic circuit (6), i.e. to all or a part of the free surface to which it is arranged.

[0016] The device (1) optionally comprises a layer L3 (5) of an adhesive or an adhesive precursor, which is arranged on all or a part of the free surface of the stack formed by the layer L1 (3), the at least one electronic circuit (6) and, if applicable, the layer L2 (4) and adheres to all or a part of the free surface of the stack formed by the layer L1 (3), the at least one electronic circuit (6) and, if applicable, the layer L2 (4), i.e. to all or a part of the free surface to which it is arranged.

[0017] According to a second aspect, the present application relates to a composite (11) comprising a) a layer LI (3) of a polymer composition cl, b) at least one electronic circuit (6) comprising at least one transducer (60), and optionally one or more electrically conductive tracks (71, 72), said at least one electronic circuit being arranged on all or part of the layer LI (3) and adhering to the layer LI, said transducer (6) comprising at least two electrically conductive electrodes (61, 62; 66, 67) separated by one or more layers (63; 68) of an electroactive polymer composition, c) optionally, a layer L2 (4) of a polymer composition c2, arranged on and adhering to all or part of the free surface of the stack formed by the layer LI (3) and said at least one electronic circuit (6), d) a layer L3' (7) of an adhesive, said layer L3' being arranged on and adhering to all or part of the free surface of the stack formed by the layer LI (3), said at least one electronic circuit (6) and, if applicable, the layer L2 (4), and e) a submount (10) arranged on and adhering to the layer L3' (7).

[0018] According to some embodiments of aspect 1 (device) and aspect 2 (composite), the electroactive polymer composition consists essentially of, or consists of, an electroactive fluoropolymer.

[0019] According to some embodiments of aspect 1 (device) and aspect 2 (composite), the electroactive fluoropolymer comprises recurring units derived from vinylidene fluoride (VDF) and trifluoroethylene (TrFE), the molar proportion of units derived from TrFE being between 15% and 50% relative to the total number of moles of units derived from VDF and TrFE.

[0020] According to some embodiments of aspect 1 (device) and aspect 2 (composite), the electroactive fluoropolymer consists essentially of, or consists of, recurring units derived from vinylidene fluoride (VDF) and trifluoroethylene (TrFE), and optionally at least one recurring unit derived from a monomer X, said monomer X being different from vinylidene fluoride, having the formula CX1X2=CX3X4, wherein each group X1, X2, X3 and X4 is independently selected from H, CI, F, Br, I and C1-C3 alkyl, which is optionally partially or totally halogenated.

[0021] According to some embodiments of aspect 1 (device) and aspect 2 (composite), the electroactive fluoropolymer is P(VDF-TrFE), P(VDF-TrFE-CTFE) or P(VDF-TrFE-CFE) or a mixture thereof.

[0022] According to some embodiments of aspect 1 (device) and 2 (composite),

[0023] The composition cl of layer LI and, if applicable, the composition c2 of layer L2 independently of each other consist essentially of or consist of a polymer comprising more than 40 wt% of fluorinated monomers and / or a polymer comprising more than 40 wt% of repeating units derived from acrylic or methacrylic monomers. Advantageously, the composition cl of layer LI and, if applicable, the composition c2 of layer L2 consist essentially of or consist of P(VDF-TrFE), P(VDF-TrFE-CTFE), P(VDF-TrFE-CFE), PVDF, PMMA or a mixture thereof. According to some particular embodiments, wherein the device or composite comprises a layer L2, cl and c2 can have the same chemical composition.

[0024] According to some embodiments of aspect 1 (device) and aspect 2 (composite), the device and / or the composite do not comprise a layer L2.

[0025] According to some embodiments of aspect 1 (device) and 2 (composite), the adhesive or adhesive precursor of the optional layer L3, or the adhesive of the layer L3’, respectively, is selected from the group consisting of water-based adhesives, contact adhesives, two-component adhesives and sealants, thermosetting adhesives, adhesives and sealants that polymerize under the action of moisture, and pressure-sensitive adhesives or self-adhesives.

[0026] According to some embodiments of aspect 1 (device) and aspect 2 (composite), the at least one transducer (60) is a layered transducer composed of a first electrode layer (61), one or more layers of electroactive composition (63) and a second electrode layer (62).

[0027] According to some embodiments of aspect 1 (device) and aspect 2 (composite), the at least one transducer (60) is an interdigital transducer composed of two comb-shaped electrodes (66, 67) and a layer of electroactive composition (68), the two electrodes and the layer of electroactive composition being arranged in the same plane.

[0028] According to some embodiments of aspect 1 (device) and aspect 2 (composite), the at least one electronic circuit (6) comprises one or more electrically conductive tracks (71, 72) in electrical contact with one or more of the electrodes (61, 62; 66, 67) of the at least one transducer (60).

[0029] According to some embodiments of aspects 1 (device) and 2 (composite), the thickness of the layer L1 (3) ranges from 1 pm to less than 100 pm and preferably from 2 pm to 20 pm.

[0030] According to some embodiments of aspect 1 (device), the mother substrate comprises, consists essentially of, or consists of a non-fluoropolymer, preferably selected from polyethylene (PE), polypropylene (PP), polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT) or polyethylene naphthalate (PEN), polyamides or co-polyamides such as PA 11, PA 12, PA 6, PA 6.6, PA 6.10, polyacrylonitrile (PAN) and mixtures thereof. The mother substrate can consist essentially of, or consist of polyethylene terephthalate.

[0031] According to some embodiments of aspect 1 (device), the device does not comprise a layer L3. In these embodiments, the device can comprise a layer L2.

[0032] According to some embodiments of aspect 1 (device), the layer L1 (3) is arranged on all or part of the surface of the mother substrate (2), the layer L1 (3) having a low adhesion to the mother substrate (2) which is sufficiently high to prevent any delamination of the mother substrate (2) and the layer L1 (3) on the surface S M-T when a low stress is applied to said device, and sufficiently low to allow adhesion failure on the surface S M-T when a medium stress is applied to said device, said surface S M-T corresponding to the projection of the surface S T on the mother substrate (2). M According to some embodiments of aspect 1 (device), the layer L1 (3) is arranged on all or part of the surface of the mother substrate (2), the layer L1 (3) having a low adhesion to the mother substrate (2) which is sufficiently high to prevent any delamination of the mother substrate (2) and the layer L1 (3) on the surface S

[0033] According to some embodiments of aspect 1 (device), a layer (8) of temporary adhesive is interposed between said mother substrate (2) and said layer L1 (3) on all or part of the surface S L1 . Said temporary adhesive can in particular be in particular a water-soluble adhesive, for example polyvinyl alcohol.

[0034] According to some embodiments of aspect 1 (device), a layer (9) of anti-adhesive is interposed between said mother substrate (2) and said layer L1 (3) on part of the surface S L1 . The anti-adhesive can be for example lecithin. The layer (9) of anti-adhesive can be interposed between said mother substrate (2) and said layer L1 (3) on at least one surface S M-T corresponding to the projection of the surface S M-T T ​on the surface S of the mother substrate (2). M

[0035] According to some embodiments of aspect 2 (composite), the sub- substrate (10) is a stretchable or deformable substrate and / or a substrate having surface irregularities, in particular surface roughness.

[0036] According to some embodiments of aspect 2 (composite), the sub- substrate (10) is selected from the group consisting of thermoplastic composites, thermoset composites, metals, metal alloys, woven or nonwoven fabrics, wood, paper, plaster, skin and leather.

[0037] According to a third aspect, the application relates to a method for manufacturing a device according to the application, comprising:

[0038] - providing said mother substrate;

[0039] - an optional step of treating the surface S of said mother substrate, comprising applying an adhesive, a temporary adhesive and / or an anti-adhesive agent; M

[0040] - printing said layer L1 on the optionally treated mother substrate;

[0041] - printing said at least one electronic circuit on layer L1 ;

[0042] - an optional step of printing said layer L2 on all or part of the free surface of the stack formed by the printed layer L1 and said at least one printed electronic circuit; and

[0043] - an optional step of depositing said layer L3 on all or part of the free surface of the stack formed by the printed layer L1, said at least one printed electronic circuit and, if applicable, the printed layer L2.

[0044] According to some embodiments, the printing of layer L1 (3), the printing of said at least one electronic circuit (6) and the optional step of printed layer L2 (4) are independently from each other carried out by a method selected from the group consisting of spin coating, spray coating, coating, in particular rod coating, slot die coating, dip coating, roll-to-roll printing, screen printing, flexographic printing, lithographic printing, electrospinning and inkjet printing. According to a particular embodiment, the printing of layer L1 (3), the printing of said at least one electronic circuit (6) and the optional step of printed layer L2 (4) are carried out by screen printing.

[0045] According to some embodiments of aspect 3 (method), the method comprises a step of polarizing said at least one printed electronic circuit.

[0046] ​​According to some embodiments of aspect 2, the sub- substrate (10) is a stretchable or deformable substrate and / or a substrate having surface irregularities and in particular surface roughness.

[0047] According to some embodiments of aspect 2, the sub- substrate (10) is selected from the group consisting of thermoplastic composites, thermoset composites, metals, metal alloys, woven or non-woven fabrics, wood, paper, plaster, skin and leather.

[0048] Finally, according to a fourth aspect, the application relates to a method of transferring a device from a mother substrate to a sub- substrate, comprising i) providing a device according to the application and a sub- substrate, ii) depositing said device on said sub- substrate by means of an adhesive and removing the mother substrate. BRIEF DESCRIPTION OF DRAWINGS

[0049] According to Figures 1 to 15 The application will be more clearly understood and will be more fully disclosed in the detailed description of the application presented below, in view of the presentation of various embodiments shown.

[0050] [ Figure 1 ] shows a front view of a device 1 comprising only the essential elements of the application, with layer L1 in direct contact with the mother substrate (2).

[0051] [ Figure 2 ] shows a front view of a device 1 comprising layer L3 (5).

[0052] [ Figure 3 ] shows a front view of a device 1 comprising layer L2 (4) and layer L3 (5).

[0053] [ Figure 4 ] shows a top view of a device 1 according to Figure 1 .

[0054] [ Figure 5 ] shows the surfaces S M , S L1 and S T of various elements of a device 1 according to Figure 1 and Figure 4 .

[0055] [ Figure 6 ] shows the surfaces of various elements of a device 1 according to Figure 1 and Figure 4 projected onto the surface S M of the mother substrate 2.

[0056] [ Figure 7 ] shows a front view of a device 1 with a layer (8) of temporary adhesive interposed between the mother substrate (2) and layer L1 (3).

[0057] [Figure 8 A front view of the device 1 is shown, in which the layer of anti-adhesive agent (9) is inserted on at least a portion of the surface S between the mother substrate (2) and the layer L1 (3). M-T The above.

[0058] [ Figure 9 A front view of the device 1 is shown, in which the layer of anti-adhesive agent (9) is inserted on at least a portion of the surface S between the mother substrate (2) and the layer L1 (3). M-L1 The above.

[0059] [ Figure 10 A cross-section (perpendicular to the printing plane) of the “layered” transducer 60 is shown.

[0060] [ Figure 11 An exploded perspective view of the electronic circuit (6) of the layered transducer 60 of the type shown in Figure 7 .

[0061] [ Figure 12 A top view of the electronic circuit (6) of the layered transducer 60 of the type shown in Figure 7 .

[0062] [ Figure 13 A view of the “interdigital” transducer 60 in the printing plane is shown.

[0063] [ Figure 14 A front view of the composite 11 obtained by transferring the device according to Figure 1 or according to Figure 2 to the sub- substrate 10 is shown.

[0064] [ Figure 15 A front view of the composite 11 obtained by transferring the device according to Figure 3 to the sub- substrate 10 is shown. DETAILED DESCRIPTION

[0065] The present application is now described in greater detail and in a non-limiting manner in the following description.

[0066] Figures 1 to 3 Various embodiments of the device (1) according to the present application are schematically shown.

[0067] With reference to Figure 1 , the device (1) according to the present application comprises a mother substrate (2), a layer L1 (3) of a polymeric composition cl arranged on a portion of the mother substrate (2), and an electronic circuit (6) arranged on a portion of the layer L1 (3) and adhered to the layer L1. The layer L1 (3) is removably fixed to the mother substrate (2). Various methods of removable fixing are disclosed below in Figures 7 to 9 .

[0068] This structure is particularly advantageous because it makes it possible to separate the layer LI and the printed substrate (or mother substrate) of the electronic circuit from the final substrate (or daughter substrate). This makes it possible to use the electronic circuit encapsulated by the layer LI on any type of surface, including for example irregular surfaces (for example very rough), stretchable substrates (for example a fabric) or surfaces with a radius of curvature. In addition, advantageously, as will be seen below, the method for transferring this device does not require a hot-pressing step or any other step that can cause a deterioration of the piezoelectric properties of the electronic circuit and / or damage to the final substrate (daughter substrate).

[0069] With reference to Figure 2 , the device (1) is the same as in Figure 1 and further comprises a layer L3 (5) of adhesive or adhesive precursor, arranged on the free surface of the stack formed by the layer LI (3) and the at least one electronic circuit (6).

[0070] With reference to Figure 3 , the device (1) is the same as in Figure 1 and further comprises a layer L2 (4) of polymeric composition c2, arranged on a portion of the free surface of the stack formed by the layer LI (3) and the electronic circuit (6), and further comprises a layer L3 (5) of adhesive or adhesive precursor, arranged on the free surface of the layer L2 (4).

[0071] Figures 4 to 6 Various relative surfaces of the device according to Figure 1 are shown.

[0072] Figure 4 is a top view of the device (1) according to Figure 1 . With reference to Figure 5 , the free surface of the mother substrate (2) before the deposition of the layer LI (3) is the surface S M , the free surface of the layer LI before the deposition of the electronic circuit (6) is the surface S L1 , and the free surface of the electronic circuit (6) is the surface S T .

[0073] By projecting the surfaces S T and S L1 onto S M , respectively, it is possible to subdivide the surface S M into three distinct surfaces: S M0 , S M-L1 and S M-T .

[0074] This gives: S T = S M-T ; S L1 = S M-T+S M-L1 ; and S M = S M-T +S M-L1 +S M0 .

[0075] In the device according to the application, the mother substrate (2) must have a low adhesion at least on the surface S M-T , since once the electronic circuit has been transferred onto the daughter substrate, the layer L1 covering the electronic circuit must be able to act as an encapsulant and protect the electronic circuit over its entire surface. This layer in particular has the role of protecting the electronic circuit from moisture, oxygen, chemical attack and mechanical attack (impact, scratching).

[0076] The layer L1 (3) can be fixed to the mother substrate (2) in various ways, detachably:

[0077] - the polymer composition cl of the layer S L1 may have little affinity for the surface of the mother substrate (2). This is generally the case when the polymer composition cl of the layer S L1 consists essentially of a fluoropolymer or consists of a fluoropolymer, and the substrate consists essentially of a non-fluoropolymer selected from polyethylene (PE), polypropylene (PP), a polyester (such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT) or polyethylene naphthalate (PEN)), a polyamide or co-polyamide (such as PA 11, PA 12, PA 6, PA 6.6, PA 6.10), polyacrylonitrile (PAN), and mixtures thereof, and preferably polyethylene terephthalate (PET).

[0078] - with reference to Figure 7 , a layer (8) of temporary adhesive can be inserted between the mother substrate (2) and the layer L1 (3) on all or part of the surface S L1 , for example on the surface S M-T , or on the surface S M-L1 , or on the surface S L1 . Such a temporary adhesive is for example polyvinyl alcohol, known to be soluble in water.

[0079] - with reference to Figure 8 and Figure 9 , a layer (9) of anti-adhesive can be inserted between the mother substrate (2) and the layer L1 (3) on part of the surface S L1 . The anti-adhesive can be for example lecithin.

[0080] Figure 8 is shown in which the anti-adhesive (9) covers at least the surface S M-TThe implementation scheme has the following advantages: once the electronic circuitry is transferred to the sub-substrate, the surface of layer L1 (3) covering the electronic circuitry is protected to prevent any risk of damage during removal of the mother substrate (2). In this embodiment, the surface of layer L1 adhered to the mother substrate is surface S. M-L1 All or part of it. The adhesion of the portion of layer L1 adhered to the mother substrate can be low or high, provided that in these embodiments, the mother substrate can be removed from the device, for example by cutting around the area with good adhesion.

[0081] Figure 9 This shows that the anti-adhesion agent (9) at least partially covers the surface S. M-L1 The implementation scheme has the advantage of creating a gripping area, allowing layer L1(3) to be separated from the mother substrate (2). In this implementation scheme, the adhesion of layer L1(3) to the mother substrate must be low over the entire portion excluding the anti-adhesion agent.

[0082] Figure 10 and Figure 11 A “layered” transducer (60) is shown, formed by stacking a first electrode (62), an electroactive polymer composition (63), and a second electrode. Conductive traces (72) and (71) in electrical contact with the electrodes enable the formation of an electronic circuit (6). Figure 12 The diagram shows a circuit comprising multiple transducers (60) interconnected by conductive traces (71, 72). Figure 11 As can be seen, the electroactive polymer composition layer (63) extends advantageously beyond the electrode to prevent any accidental short circuit.

[0083] Figure 13 An interdigital transducer (60) is shown, wherein the electrodes (66, 67) and the electroactive polymer composition layer are both in the same plane.

[0084] Figure 14 A composite (11) is shown, comprising a) a layer L1 (3) of polymer composition c1, an electronic circuit (6) disposed on a portion of layer L1 (3) and adhered to layer L1, an adhesive layer L3' (7) disposed on a free surface of a stack formed by layer L1 (3) and electronic circuit (6), and a sub-substrate (10) disposed on layer L3' (7).

[0085] Figure 14 The composite (11) is shown, which also includes a layer L2 (4) inserted between the electronic circuit (6) and layer L3' (7).

[0086] Mother substrate

[0087] The mother substrate can comprise, consist essentially of, or consist of a non-fluoropolymer, preferably selected from polyethylene (PE), polypropylene (PP), polyesters (e.g. polyethylene terephthalate (PET), polybutylene terephthalate (PBT) or polyethylene naphthalate (PEN)), polyamides or co-polyamides (e.g. PA 11, PA 12, PA 6, PA 6.6, PA 6.10), polyacrylonitrile (PAN) and mixtures thereof.

[0088] The mother substrate is preferably PET.

[0089] Layers (L1) and (L2)

[0090] The composition c1 of the layer L1 and, if applicable, the composition c2 of the layer L2 can independently of each other essentially consist of or consist of a polymer comprising more than 40 wt% of fluorine-containing monomers and / or a polymer comprising more than 40 wt% of repeating units derived from acrylic or methacrylic monomers.

[0091] Advantageously, the composition c1 of the layer L1 and, if applicable, the composition c2 of the layer L2 independently of each other essentially consist of or consist of P(VDF-TrFE), P(VDF-TrFE-CTFE), P(VDF-TrFE-CFE), PVDF, PMMA or mixtures thereof.

[0092] These polymers have the advantage of having a good affinity with the electrically active composition of the polymer of the electronic circuit, which makes it possible to create a good adhesion between the layer L1 and the layer of electrically active polymer composition, which usually extends beyond the electrode, and, if applicable, between the layer L2 and the layer of electrically active polymer composition, which usually extends beyond the electrode.

[0093] According to some particular embodiments, wherein the device or composite comprises a layer L2, c1 and c2 can have the same chemical composition.

[0094] The thickness of the layer L1 is preferably comprised between 1 and less than 100 pm and preferably between 2 and 20 pm.

[0095] The thickness of the layer L2, if present, is preferably comprised between 1 and less than 100 pm and preferably between 2 and 20 pm.

[0096] Electronic circuit

[0097] The electrode and / or the conductive tracks can in particular be formed from a conductive polymer composition or a conductive metal-based composition, for example the composition can be a PEDOT:PSS composition (PEDOT = poly(3,4-ethylenedioxythiophene, PSS = poly(styrenesulfonate)), or a silver-based composition, for example silver, copper or carbon nanowires, for example graphene. The solutions based on these materials are generally aqueous solutions.

[0098] The electrode layer and / or the conductive tracks preferably have a thickness of between 0.5 pm and 5 pm, and preferably between 0.8 pm and 2 pm.

[0099] The layer of electroactive polymer composition preferably has a thickness of between 1 pm and less than 100 pm, preferably between 2 pm and 50 pm, and more preferably between 3 pm and 10 pm.

[0100] The electroactive polymer composition can consist essentially of or consist of an electroactive fluoropolymer.

[0101] According to some preferred embodiments, the electroactive fluoropolymer comprises recurring units derived from vinylidene fluoride (VDF) and trifluoroethylene (TrFE), the molar proportion of units derived from TrFE being between 15% and 50% relative to the total number of moles of units derived from VDF and TrFE.

[0102] Depending on the end use of the electronic circuit, the electroactive fluoropolymer can consist essentially of or consist of recurring units derived from vinylidene fluoride (VDF) and trifluoroethylene (TrFE), and optionally at least one recurring unit derived from a monomer X, which is different from vinylidene fluoride, having the formula CX1X2=CX3X4, in which each group X1, X2, X3and X4is independently selected from H, CI, F, Br, I and C1-C3alkyl, which is optionally partially or totally halogenated.

[0103] The electroactive fluoropolymer can be P(VDF-TrFE), P(VDF-TrFE-CTFE) or P(VDF-TrFE-CFE) or mixtures thereof.

[0104] The well-known solvents of these polymers in which they can be dissolved are, for example, methyl ethyl ketone (MEK), triethyl phosphate (TEP), cyclohexanone, gamma-butyrolactone or ethyl acetate.

[0105] Adhesive layer

[0106] The adhesive or adhesive precursor of the optional layer L3 or the adhesive of the layer L3’ can be chosen, respectively, from water-based adhesives, contact adhesives, two-component adhesives and sealants, thermosetting adhesives, adhesives and sealants that polymerize under the action of moisture, and pressure-sensitive adhesives or self-adhesives.

[0107] Substrate

[0108] The sub substrate can be of any type and its properties are not limited. The substrate can for example be a plastic substrate, a metal substrate, a stretchable or deformable substrate, or a substrate having surface irregularities such as surface roughness. For example, the sub substrate can be a plastic substrate, a metal substrate, a fabric (in particular leather, cotton, synthetic fibers, etc.), wood, plaster, human skin, etc.

[0109] The application also relates to a method for manufacturing a device according to the application, comprising:

[0110] - providing the mother substrate;

[0111] - an optional step of treating the surface S of the mother substrate, comprising the application of an adhesive, a temporary adhesive and / or an anti-adhesive agent; M

[0112] - printing the layer L1 on the optionally treated mother substrate;

[0113] - printing the at least one electronic circuit on the layer L1 ;

[0114] - an optional step of printing the layer L2 on all or part of the free surface of the stack formed by the printed layer L1 and the at least one printed electronic circuit; and

[0115] - an optional step of depositing the layer L3 on all or part of the free surface of the stack formed by the printed layer L1, the at least one printed electronic circuit and, if applicable, the printed layer L2.

[0116] According to some embodiments, the printing of the layer L1 (3), the printing of the at least one electronic circuit (6) and the optional step of printing the layer L2 (4) can be implemented independently of one another by a method chosen from the group consisting of spin coating, spray coating, coating, in particular bar coating, slot die coating, dip coating, roll-to-roll printing, screen printing, flexographic printing, lithographic printing, electrospinning and inkjet printing.

[0117] According to some embodiments, the printing of the layer L1 (3) and the optional step of printing the layer L2 (4) can be implemented by coating, in particular bar coating, and / or the printing of the at least one electronic circuit (6) is implemented by screen printing.

[0118] ​When the electroactive polymer is a ferroelectric polymer, the method can comprise a step of polarizing the electronic circuit after it has been printed and / or coated with the optional layer L2.

[0119] Finally, the application relates to a method of transferring a device from a mother substrate to a daughter substrate, comprising:

[0120] i) providing a device according to the application;

[0121] ii) depositing said device on said daughter substrate by means of an adhesive; and

[0122] iii) removing said mother substrate.

[0123] Example

[0124] A mother substrate consisting of a polyethylene terephthalate A4 sheet of thickness 120 μιη (PET; Melinex® 506 sold by the company Dupont) was used.

[0125] A 17%wt P(VDF-co-TrFE) solution in triethyl phosphate (VDF:TrFE 80%mol:20%mol; Piezotech® FC sold by the company Arkema) was deposited by coating on the substrate. The coating bar was adjusted so that the final layer after evaporation of the solvent was 1 micron thick. The solvent was evaporated by placing the mother substrate and its coating in an oven at 130°C for 20 minutes. A layer L1 of P(VDF-co-TrFE) was thus printed on the surface of the mother substrate.

[0126] The transducer was screen printed on the layer L1 according to the following parameters:

[0127] 1) PEDOT-PSS (Orgacon® ELP-3155, Agfa). 0.5 μιη deposited after evaporation using a dedicated screen. Evaporation of the solvent in an oven at 140°C for 10 minutes.

[0128] 2) Ink P (P(VDF-co-TrFE) 17%wt in TEP). 100-40 screen, final thickness ~ 1.5 μιη after evaporation. Evaporation of the solvent in an oven at 140°C for 20 minutes.

[0129] Step 2 was performed three times to obtain a final thickness of 4.5 μιη.

[0130] 3) PEDOT-PSS (Orgacon® ELP-3155, Agfa). 0.5 μιη deposited after evaporation using a screen. Evaporation of the solvent in an oven at 140°C for 10 minutes.

[0131] Once printing is complete, the transducer is polarized by contact application of an electric field to reach 100 V / µm. The voltage is gradually applied in 50 V intervals with a sinusoidal wave signal. This is done at ambient temperature (23 °C) and the voltage is applied to both PEDOT electrodes.

[0132] To transfer the transducer from the mother substrate to the daughter substrate, a pressure sensitive adhesive (3M™ Adhesive Transfer Tape 465) is deposited in the form of a film on the transducer.

[0133] The patch thus formed is deposited directly on the daughter substrate and pressure is applied.

[0134] The mother substrate is then carefully removed by hand. Finally, the transducer / protective layer L1 structure is deposited on the daughter substrate and the protective layer L1 is in direct contact with the ambient air.

Claims

1. An apparatus (1) suitable for transferring electronic circuitry (6) from a mother substrate (2) to a daughter substrate, comprising: a. Having surface S M The mother substrate (2); b. Has surface S L1 The polymer composition c1 has a layer L1 (3) disposed on all or part of the mother substrate (2); c. Having surface S T At least one electronic circuit (6), the at least one electronic circuit (6) comprising at least one transducer (60) and optionally one or more conductive traces (71, 72), the at least one electronic circuit being disposed on all or part of the layer L1 (3) and adhered to the layer L1, the transducer (6) comprising at least two conductive electrodes (61, 62; 66, 67) separated by one or more layers (63; 68) of an electroactive polymer composition; d. Optionally, layer L2(4) of polymer composition c2 is disposed on all or part of the free surface of the stack formed by layer L1(3) and the at least one electronic circuit (6), and adheres to all or part of the free surface of the stack formed by the at least one electronic circuit (6); and e. Optionally, an adhesive or adhesive precursor layer L3 (5) is disposed on all or part of the free surface of the stack formed by layer L1 (3), the at least one electronic circuit (6) and, if applicable, layer L2 (4), and adheres to all or part of the free surface of the stack formed by layer L1 (3), the at least one electronic circuit (6) and, if applicable, layer L2 (4); The layer L1 (3) is detachably fixed to the mother substrate (2).

2. The apparatus according to claim 1, wherein, The electroactive fluoropolymer contains repeating units derived from vinylidene fluoride (VDF) and trifluoroethylene fork (TrFE), with the molar proportion of TrFE-derived units ranging from 15% to 50% relative to the total molar number of units derived from VDF and TrFE.

3. The apparatus according to any one of claims 1 and 2, wherein the composition c1 of layer L1 and, if applicable, the composition c2 of layer L2 are independently composed substantially of, or composed of, a polymer comprising more than 40% by weight of a fluorinated monomer and / or a polymer comprising more than 40% by weight of repeating units derived from acrylic or methacrylic monomers.

4. The apparatus according to any one of claims 1 to 3, comprising the layer L2, wherein c1 and c2 have the same chemical composition.

5. The apparatus (1) according to any one of claims 1 to 4, wherein, The at least one transducer (60) is a layered transducer formed by a first electrode layer (61), a layer of electroactive composition (63), and a second electrode layer (62); or the transducer (60) is an interdigitated transducer formed by two comb-shaped electrodes (66, 67) and a layer of electroactive composition (68), wherein the two electrodes and the layer of electroactive composition are arranged in the same plane.

6. The apparatus (1) according to any one of claims 1 to 5, wherein, The at least one electronic circuit (6) includes one or more conductive traces (71, 72) that are in electrical contact with one or more electrodes (61, 62; 66, 67) of the at least one transducer (60).

7. The apparatus according to any one of claims 1 to 6, wherein the layer L1 (3) is disposed on all or part of the surface of the mother substrate (2), the layer L1 (3) having low adhesion to the mother substrate (2), the low adhesion being sufficiently high to prevent the mother substrate (2) and the layer L1 (3) from sticking together on the surface S when a low stress is applied to the apparatus. M-T Any layering on the surface, and the low adhesion is low enough to allow the surface S to be unaffected when moderate stress is applied to the device. M-T Adhesion failure on surface S M-T Corresponding to the surface S T On the surface S of the mother substrate (2) M The projection on the surface.

8. The apparatus according to any one of claims 1 to 7, wherein, Between the mother substrate (2) and the layer L1 (3) on the surface S L1 A layer of temporary adhesive is inserted into all or part of it (8).

9. A method for manufacturing an apparatus according to any one of claims 1 to 8, comprising: - Provide the mother substrate; - Process the surface S of the mother substrate M Optional steps include applying adhesives, temporary adhesives, and / or anti-adhesion agents; - Print the layer L1 onto an optionally treated mother substrate; - Print the at least one electronic circuit on layer L1; - An optional step of printing layer L2 on all or part of the free surface of the stack formed by the printed layer L1 and the at least one printed electronic circuit; and - An optional step of depositing the layer L3 on all or part of the free surface of the stack formed by the printed layer L1, the at least one printed electronic circuit, and, if applicable, the printed layer L2.

10. The manufacturing method according to claim 9, wherein, The printing of layer L1 (3) and the optional steps of printing layer L2 (4) are achieved by coating, particularly by bar coating, and / or the printing of the at least one electronic circuit (6) is achieved by screen printing.

11. The manufacturing method according to any one of claims 9 and 10, comprising the step of polarizing the at least one printed electronic circuit.

12. A method for transferring a device from a mother substrate to a daughter substrate, comprising: i) Providing the apparatus and sub-substrate according to any one of claims 1 to 8; ii) Depositing the device onto the sub-substrate using an adhesive; and iii) Remove the mother substrate.

13. A complex (11) comprising: a. Having surface S L1 Layer L1(3) of polymer composition c1; b. Has surface S T At least one electronic circuit (6), the at least one electronic circuit (6) comprising at least one transducer (60) and optionally one or more conductive traces (71, 72), the at least one electronic circuit being disposed on all or part of the layer L1 (3) and adhered to the layer L1, the transducer (6) comprising at least two conductive electrodes (61, 62; 66, 67) separated by one or more layers (63; 68) of an electroactive polymer composition; c. Optionally, layer L2 (4) of polymer composition c2 is disposed on all or part of the free surface of the stack formed by layer L1 (3) and the at least one electronic circuit (6), and is adhered to all or part of the free surface of the stack formed by layer L1 (3) and the at least one electronic circuit (6); d. An adhesive layer L3'(7), which is disposed on all or part of the free surface of the stack formed by layer L1(3), the at least one electronic circuit (6) and, if applicable, layer L2(4), and is adhered to all or part of the free surface of the stack formed by layer L1(3), the at least one electronic circuit (6) and, if applicable, layer L2(4); e. Sub-substrate (10), which is disposed on and adhered to layer L3' (7); The complex can be obtained by the transfer method according to claim 12.

14. The complex (11) according to claim 13, wherein, The sub-substrate (10) is a stretchable or deformable substrate and / or a substrate with surface irregularities, particularly surface roughness.

15. The composite (11) according to claim 13, wherein the sub-substrate (10) is selected from thermoplastic composites, thermosetting composites, metals, metal alloys, woven or nonwoven fabrics, wood, paper, plaster, skin and leather.

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