MOLDABLE AND FLEXIBLE HAPTIC MATERIALS AND STRUCTURES - Patent application

Abstract

A composition comprising a piezoelectric polymer and a binder, the composition being capable of being printed to form a haptic component during a process for forming an electronic device.

Description

[Technical field]

[0001] The present invention relates to compositions, methods of making compositions, methods of making in-mold electronic (IME) components, in-mold electronic (IME) components, capacitive touch switches, resistive touch switches, methods of forming tactile components, and tactile components. [Background technology]

[0002] In printed electronics, most human machine interface (HMI) electronic circuits, structures, and surfaces are typically fabricated by screen printing conductive and dielectric inks on thin flexible substrates. Many of these circuits / structures include resistive or capacitive touch switches. Some of these touch switches suffer from a lack of human-like "feel" for the user. While in many applications it is often the user's preference to have a tactile response or some other feedback to their actions, in other cases it is often necessary to get some kind of feedback to confirm that the correct action has been performed. For example, in-mold electronic devices such as those used on automobile dashboards should allow the user to receive non-visual feedback while turning a knob in a dark cabin. Membrane touch switch-based devices typically provide passive feedback (finger press of metal dome switch with an audible click) that relies on the touch sensation of a human finger, similar to physical knobs that rely on touch and linear or rotary motion being sensed by the human hand. In the case of capacitive touch switches, passive feedback can be introduced into the design of the physical shape of the touch location (protrusion or depression) to confirm that the user has touched the correct location. However, another form of confirmation is needed to ensure that the switch, when actuated, has performed its function, e.g., turned something on or off. The feedback can be in the form of an audible signal, or a low-intensity vibration that can be easily sensed by a human finger (a so-called "tactile feedback mechanism"). The audio signal can be generated using a speaker built using one of the existing technologies, such as an induction coil or a piezoelectric transducer, while the low-intensity vibration can be generated, for example, by an electric motor. Both techniques involve the use of an additional standalone rigid device, which adds complexity, weight, and size.

[0003] The haptic components need to be manufactured by the same printing techniques used to make the entire device fully functional, including the haptic feedback mechanism, without compromising other attributes. Summary of the Invention

[0004] The present invention aims to solve at least some of the problems associated with the prior art, or to provide a commercially acceptable alternative.

[0005] In a first aspect, the present invention provides a method for producing a composition comprising the steps of: A piezoelectric polymer; and a binder.

[0006] Each aspect or embodiment defined in this specification may be combined with any other aspect or embodiment unless expressly indicated otherwise. In particular, any feature indicated as being preferred or advantageous may be combined with any other feature indicated as being preferred or advantageous.

[0007] The inventors have surprisingly found that the composition can be used to form tactile components during a printing process to form an electronic device. Because the composition can be printed, the formation of the tactile components can be performed using similar printing techniques used to make other components of the device, such as resistive or capacitive touch switches. This can simplify the manufacture of the electronic device, thereby reducing costs. In addition, the size and weight of the electronic device can be reduced.

[0008] The composition includes a piezoelectric polymer. The term "piezoelectric" as used herein may encompass materials that accumulate charge in response to an applied mechanical stress or generate mechanical force in response to an applied electric field. Without being bound by theory, it is believed that this property arises from an electric dipole moment that occurs in certain crystal structures. In piezoelectric materials, these dipoles can be oriented or aligned by a process known as poling, in which a high voltage is applied across the material and the material can be heated to facilitate dipole alignment. After poling, ferroelectric materials also exhibit piezoelectric behavior. In the present invention, the piezoelectricity of the polymer means that the composition can be used to form a piezoelectric transducer, which may form part of a haptic component, such as a vibration or audio component, in an HMI device. Such a piezoelectric transducer can be actuated in response to being touched by a user of the HMI device.

[0009] Inorganic ceramic piezoelectric materials such as lead zirconate are known. Inorganic crystalline piezoelectric materials exhibit greater piezoelectric response than other piezoelectric materials (e.g., by generating more charge for the same amount of applied mechanical stress) and maintain their piezoelectric properties at higher temperatures than other piezoelectric materials. However, they are hard and bulky and require high temperature processing to achieve effective performance. For example, to form a piezoelectric transducer from lead zirconate, a powder of lead zirconate is combined with additives such as inert binders and fired at high temperatures, typically above 750° C., to form a solid shape. In contrast, by having the piezoelectric material in the form of a polymer, the composition of the present invention can be processed at temperatures low enough to avoid damage to typical electronic device substrates. Furthermore, the composition can have rheological properties suitable for printing, resulting in the formation of a flexible piezoelectric transducer.

[0010] The piezoelectric polymer is typically included in the composition in the form of a powder.

[0011] The composition may be printable. For example, the composition is preferably capable of undergoing screen printing, stencil printing, gravure printing, offset printing, and / or roll-to-roll printing, more preferably screen printing. Such techniques are commonly used when printing electronic components.

[0012] The composition includes a binder. Typically, the piezoelectric polymer is dispersed within the binder. The piezoelectric polymer may be blended with the binder. The binder may act to hold ("bind") the composition together and may help provide the composition with desired rheological properties.

[0013] The composition is preferably for use in the manufacture of in-mold electronic (IME) components. IME components are typically manufactured by printing electronic circuits onto a flexible substrate and then thermoforming the substrate into the desired shape in a mold. The use of a polymeric form of piezoelectric material makes the composition of the present invention flexible enough to retain its shape when thermoformed.

[0014] The composition is preferably in the form of an ink. The ink may be suitable for printing and / or other dispensing techniques used in typical methods of manufacturing electronic devices. The ink is preferably a conductive ink or a dielectric ink. Conductive and dielectric inks capable of forming tactile components may be particularly useful in the manufacture of HMI electronic devices.

[0015] The composition is preferably in the form of a paste. The paste can be suitably applied to a substrate using typical dispensing techniques used in methods for manufacturing electronic devices. The paste is preferably a conductive paste or a dielectric paste. Inductive and dielectric pastes capable of forming tactile components can be particularly useful in the manufacture of HMI electronic devices.

[0016] The piezoelectric polymer preferably comprises polyvinylidene fluoride (PVDF), which has the following chemical formula:

[0017] [ka]

[0018] PVDF can exhibit particularly advantageous piezoelectric properties and can exhibit advantageous flexibility. PVDF can also be processed at temperatures low enough to avoid damage to typical substrates used in HMI devices. Without being bound by theory, it is believed that in PVDF, the high electronegativity of the hydrogen-fluorine bond is responsible for the manifestation of piezoelectricity.

[0019] The piezoelectric polymer preferably comprises a copolymer of PVDF, more preferably polyvinylidene fluoride-trifluoroethylene copolymer (PVDF-TrFe). Although the unit structure of the copolymer may be less polar than that of pure PVDF, the copolymer may exhibit a higher degree of crystallinity. This may result in a larger piezoelectric response compared to pure PVDF. Typically, PVDF crystallizes in the non-polar α phase. Advantageously, by copolymerizing with trifluoroethylene, the fluorine atoms in trifluoroethylene inhibit the molecular structure of the polymer, and thus PVDF-TrFe may crystallize directly in the ferroelectric β phase. The mass ratio of PVDF to comonomer may range from 30:70 to 70:30, or 45:55 to 55:45, or 60:40 to 70:30.

[0020] The composition preferably comprises 5-95 wt. % piezoelectric polymer, preferably 15-70 wt. % piezoelectric polymer, more preferably 20-60 wt. % piezoelectric polymer, and 5-95 wt. % binder, preferably 30-85 wt. % binder, more preferably 40-80 wt. % binder, based on the total weight of the composition, which may result in a particularly advantageous combination of high piezoelectric response and suitable rheological properties.

[0021] The binder preferably comprises a thermoplastic resin containing hydroxyl groups, a crosslinking agent, and a solvent. The term "thermoplastic resin" as used herein may encompass plastic polymeric materials that become flexible or moldable at a certain elevated temperature and solidify upon cooling. The use of a thermoplastic resin may ensure that the composition is suitably flexible during thermoforming, but solid in the final electronic device. The crosslinking agent may react with the hydroxyl groups at elevated temperatures to "cure" the composition. The solvent may serve to dissolve the thermoplastic resin, the crosslinking agent, and any other components of the binder.

[0022] The thermoplastic resin preferably has a glass transition temperature below 100° C. and / or a softening point below 100° C. This may make the composition particularly susceptible to thermoforming.

[0023] The thermoplastic resin preferably comprises one or more of polyurethane resins, polyester resins, polyacrylate resins, polyvinyl ester resins, phenoxy resins, and ketone resins. Such resins are particularly suitable for use in the present invention and react with crosslinks under the drying conditions of a typical IME manufacturing process to provide the desired degree of crosslinking.

[0024] The thermoplastic resin preferably comprises, based on the total weight of the thermoplastic resin, 20-60% by weight of polyurethane resin, preferably 35-47% by weight of polyurethane resin, 5-30% by weight of polyester resin, preferably 13-19% by weight of polyester resin, and 20-60% by weight of phenoxy resin, preferably 34-51% by weight of phenoxy resin. Such ratios of components may provide the composition with particularly advantageous rheological, curing, and / or adhesive properties.

[0025] Preferably, the thermoplastic resin is and / or and / or has a glass transition temperature of less than 100°C; and / or has a weight average molecular weight of 1000 to 100000 g / mol; have a softening point of less than 100°C, and / or It has a hydroxyl content (OH number) of more than 20 mg KOH / g.

[0026] This may make the composition particularly susceptible to thermoforming. A high hydroxyl number may advantageously result in a high level of crosslinking upon curing.

[0027] The crosslinking agent preferably comprises one or more of melamine resins, amino resins, polyamine resins, isocyanates, and polyisocyanates, more preferably melamine formaldehyde, and even more preferably hexamethoxymethylmelamine. Such species can react favorably with the hydroxyl groups of the thermoplastic resin, thereby advantageously resulting in a high degree of crosslinking.

[0028] The crosslinking agent preferably further comprises an isocyanate and / or a polyisocyanate and / or a blocked polyisocyanate, which can increase the level of crosslinking.

[0029] The solvent preferably comprises one or more of an alcohol, glycol, glycol ether, glycol ester, ester, ketone, and hydrocarbon. Such species may be particularly suitable for dissolving the components of the binder and may provide the composition with desirable rheological properties.

[0030] The solvent preferably comprises, based on the total weight of the solvent, up to 95% by weight of glycol ether acetate, preferably up to 85% by weight of glycol ether acetate, and / or up to 95% by weight of glycol ether, preferably up to 85% by weight of glycol ether, and / or up to 15% by weight of ester, preferably up to 5% by weight of ester, and / or up to 40% by weight of ketone, preferably up to 32% by weight of ketone, and / or up to 80% by weight of alcohol, preferably up to 70% by weight of alcohol, and / or up to 30% by weight of hydrocarbon, preferably up to 22% by weight of hydrocarbon. Such a ratio may make the solvent particularly suitable for dissolving the components of the binder and may provide a composition with desired rheological properties.

[0031] The binder preferably comprises, based on the total weight of the binder, 10-40 wt. % thermoplastic resin, preferably 11-30.4 wt. % thermoplastic resin, 0.5-12 wt. % crosslinker, preferably 1.5-7.7 wt. % crosslinker, and 40-85 wt. % solvent, preferably 46.7-78.8 wt. % solvent.

[0032] The binder preferably further comprises a thermosetting resin, more preferably a thermosetting resin including one or both of an acrylic resin and an epoxy resin, and a curing catalyst for curing the thermosetting resin, preferably a curing catalyst for thermally curing the thermosetting resin and / or for UV curing the thermosetting resin. The presence of the thermosetting resin and the curing catalyst may act to form a three-dimensional thermosetting network. This may be beneficial when the dried composition is required to have more "thermosetting" properties.

[0033] The binder preferably further comprises one or more functional additives, preferably selected from one or more of surfactants, rheology modifiers, dispersants, defoamers, anti-blocking agents, slip additives, anti-sag agents, leveling agents, surface active agents, surface tension reducing agents, adhesion promoters, anti-skinning agents, matting agents, colorants, dyes, pigments, and wetting agents.

[0034] The binder preferably comprises, based on the total weight of the binder, 0.5 to 12 wt. % of a crosslinking agent, preferably 1.5 to 7.7 wt. % of a crosslinking agent, 10 to 40 wt. % of a thermoplastic resin, preferably 11 to 30.4 wt. % of a thermoplastic resin, 40 to 85 wt. % of a solvent, preferably 46.7 to 78.8 wt. % of a solvent, and optionally 0.1 to 30 wt. % of a thermosetting resin and 0.1 to 3 wt. % of a curing catalyst for curing the thermosetting resin, preferably 1 to 10 wt. % of a thermosetting resin and 0.1 to 1 wt. % of a curing catalyst for curing the thermosetting resin, and / or 0.1 to 20 wt. % of a functional additive, preferably 1.7 to 17 wt. % of a functional additive.

[0035] In a further aspect, the present invention provides a method of making the compositions described herein, comprising the steps of: Providing a solvent; Providing a thermoplastic resin having a hydroxyl group; Dissolving a thermoplastic resin in a solvent at a temperature of 50 to 100°C, preferably 70 to 100°C; Cooling the solution to room temperature; adding to the cooled solution a piezoelectric polymer, a crosslinker, and optionally one or more of a functional additive, a thermosetting resin, a curing catalyst for curing the thermosetting resin, conductive particles, and non-conductive particles.

[0036] The advantages and preferred features of the first aspect apply equally to this aspect.

[0037] Dissolving the thermoplastic resin in a solvent at elevated temperatures may facilitate dissolution of the thermoplastic resin.

[0038] In a further aspect, the present invention provides a method of manufacturing an in-mold electronic (IME) component, comprising the steps of: Preparing a blank; and thermoforming the blank; Preparing the blank includes forming one or more structures on a thermoformable substrate, each structure comprising: disposing a composition described herein on a thermoformable substrate; and drying the composition at a temperature of 20 to 150° C. for 0.5 to 60 minutes.

[0039] The advantages and preferred features of the first aspect apply equally to this aspect.

[0040] The term "thermoforming" as used herein may encompass a manufacturing process in which a plastic sheet is heated to a pliable forming temperature, formed into a specific shape in a mold, and trimmed to create a usable product. The sheet is typically heated in an oven to a high enough temperature to allow it to be stretched into or over the mold and cooled to the final shape. A simplified version of that is vacuum forming. Pressure may be applied during thermoforming. Thermoforming may include high pressure thermoforming.

[0041] Drying the composition can include evaporating the solvent from the composition. Typically, most of the solvent is removed from the composition, and more typically, substantially all of the solvent is removed from the composition.

[0042] The one or more structures preferably comprise a multi-layer laminate.

[0043] The composition is preferably exposed to an electric field, which can align most of the dipoles in the polymer chains, thereby making the polymer piezoelectric. The composition can be exposed to the electric field before being disposed on the substrate, after being disposed on the substrate but before being thermoformed, or after being thermoformed. The composition is preferably exposed to the electric field at an elevated temperature, which can promote the alignment of the dipoles.

[0044] The method preferably further comprises disposing one or more conductive or dielectric inks on the thermoformable substrate prior to disposing the composition described herein on the thermoformable substrate. In such a case, disposing the composition described herein on the thermoformable substrate comprises disposing the composition on one or more conductive or dielectric inks disposed on the thermoformable substrate. The method may preferably further comprise subsequently disposing one or more conductive or dielectric inks on the composition. Thus, the blank may comprise a thermoformable substrate having thereon a layer of the composition sandwiched between one or more layers of conductive and / or dielectric inks. This may result in the tactile component being integrated with a capacitive or resistive touch switch.

[0045] The one or more structures preferably include a haptic structure, more preferably an audio speaker or a mechanical vibration device.

[0046] Disposing the composition preferably comprises printing the composition, more preferably screen printing, stencil printing, gravure printing, offset printing, and / or roll-to-roll printing the composition, even more preferably screen printing the composition.

[0047] The substrate preferably comprises one or more of polyethylene terephthalate (PET), polycarbonate (PC), paper, polymethyl methacrylate (PMMA), polyethylene nephalate (PEN), polyimide (PI), and thermoplastic polyurethane (TPU). The compositions described herein may be miscible with such materials and may form strong bonds with such materials. Such materials also exhibit favorable thermoforming properties.

[0048] Thermoforming is preferably carried out at a temperature between 140°C and 210°C. Such conditions may result in particularly advantageous thermoforming without causing damage to the substrate and / or decomposition of the components of the composition. Such temperatures are particularly suitable for thermoforming, and the compositions described herein may be stable at such temperatures. Thermoforming may include vacuum thermoforming. In a preferred embodiment, vacuum thermoforming is carried out at a pressure between 0.25 MPa and 0.4 MPa. In another preferred embodiment, high pressure thermoforming is carried out at a pressure in the range of 6 MPa to 12 MPa.

[0049] The method preferably further comprises applying a layer of resin to the substrate using injection molding after thermoforming, preferably the resin comprises one or more of polycarbonate (PC), polyethylene terephthalate (PET), acrylonitrile butadiene styrene (ABS), polypropylene (PP), polyester, poly(methyl methacrylate) (PMMA), low density polyethylene (LDPE), high density polyethylene (HDPE), polystyrene (PS), and thermoplastic polyurethane (TPU). Other similar resins may also be used. Such a resin layer may provide the final IME component with advantageous mechanical and / or aesthetic properties.

[0050] Injection molding is preferably carried out at a temperature of 170 to 330° C. Such temperatures are particularly suitable for injection molding, and the compositions described herein may be stable at such temperatures.

[0051] Preparing the blank preferably further includes forming one or more conductive and / or dielectric layers over the substrate and / or structure.

[0052] The in-mold electronics (IME) components preferably include capacitive touch switches, resistive touch switches, or capacitive touch sensors.

[0053] The in-mold electronic (IME) components preferably include one or more of a display, a light / lamp, a sensor, an indicator, and a haptic / touch feedback device.

[0054] In a further aspect, the present invention provides an in-mold electronic (IME) component manufactured according to the methods described herein.

[0055] The advantages and preferred features of the first aspect apply equally to this aspect.

[0056] In a further aspect, the present invention provides an in-mold electronic (IME) component comprising the composition described herein.

[0057] The advantages and preferred features of the first aspect apply equally to this aspect.

[0058] In a further aspect, the present invention provides an in-mold electronic (IME) component comprising a piezoelectric polymer.

[0059] The advantages and preferred features of the first aspect apply equally to this aspect.

[0060] The in-mold electronic (IME) components of the last three embodiments preferably include haptic components.

[0061] In a further aspect, the present invention provides a capacitive or resistive touch switch that includes the in-mold electronic (IME) components described herein.

[0062] The advantages and preferred features of the first aspect apply equally to this aspect.

[0063] The tactile component is preferably sandwiched between two electrodes, more preferably one of the electrodes includes a touchpad.

[0064] The tactile component is preferably a dielectric material.

[0065] The capacitive touch preferably further includes a dielectric layer located between the tactile component and each electrode.

[0066] In a further aspect, the present invention provides a method of forming a haptic component, the method comprising: Providing a substrate; disposing a composition described herein on a substrate; and drying the composition at a temperature of 20 to 150°C for 0.5 to 60 minutes.

[0067] The advantages and preferred features of the first aspect apply equally to this aspect.

[0068] In a further aspect, the present invention provides tactile components formed using the methods described herein or comprising the compositions described herein.

[0069] The advantages and preferred features of the first aspect apply equally to this aspect. [Brief description of the drawings]

[0070] The invention will now be further described with reference to the following drawings. [Figure 1a] 1 is a photograph of a touchpad formed using a composition of the present invention. [Figure 1b] 1 is a photograph of a touchpad formed using a composition of the present invention. [Figure 1c] 1 is a photograph of a touchpad formed using a composition of the present invention. [Diagram 2] FIG. 1 shows the electrical response displayed on an oscilloscope screen when the touchpad of FIG. 1a is repeatedly pressed with a finger. [Diagram 3] 1 shows an oscilloscope screen shot of the force sensing signal from a polymer-based haptic integrated with a capacitive touch switch. [Figure 4] 1 shows the detected force signal from a printed touch sensor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0071] The invention will now be further described with reference to the following examples.

[0072] Working Example A two-electrode touchpad was prepared according to the following method. First, a flexible polycarbonate film was prepared. A conductive silver ink was printed on the film to form a bottom electrode. Then, a composition according to the present invention in the form of an ink was printed on the bottom electrode to form a tactile layer, and a conductive silver ink was printed on the tactile layer to form a top electrode. The ink was then cured in an oven at a temperature below 120°C. The resulting touchpad is shown in Figure 1a.

[0073] Two more two-electrode touchpads were prepared using a similar method, except that after curing, these touchpads were thermoformed at temperatures between 150 and 180° C. The resulting thermoformed touchpads are shown in Figures 1b and 1c.

[0074] The touchpad in Figure 1a was connected to an oscilloscope to monitor the electrical signals generated during the experiments. During the first experiment, the center pad was repeatedly pressed with a finger to check whether an electrical signal was generated. To avoid grounding by the human body, an electrical insulating tape was attached over the top electrode.

[0075] Figure 2 shows the electrical response displayed on an oscilloscope screen when the touchpad was repeatedly pressed with a finger. No filter circuit was used between the touchpad and the oscilloscope. Thus, multiple peaks were observed for each touch, indicating a natural response and natural damping oscillations as expected. The 3D shaped touchpad (Figures 1b and 1c) also shows similar performance to the flat sample (Figure 1a). Extreme molding, where the sample is stretched beyond the limits of the material used to make it, can lead to performance degradation or failure. For example, failure in the conductive ink can be a loss of conductivity, while failure in the dielectric or tactile layer can be an increase in leakage current (loss of insulation).

[0076] FIG. 3 shows a typical electrical response from the active tactile layer underneath a capacitive touchpad made in accordance with the present invention. In this case, a known weight was placed on the touchpad. The response was recorded as the weight was quickly lifted. As expected, variation in response time was observed since the weight was lifted manually. A similar response is observed when the weight is placed on the sample. The manual nature of the experiment causes variation in the applied stimulus rate / time and therefore variation in the observed response time. The polarity of the electrical signal is not important here as it depends on the order of the probe terminals.

[0077] Figure 4 shows the total energy response of the tactile / sensor shown in Figure 1a to an applied force. The total energy response is calculated as the total integrated area under the response curve shown in Figure 3. Taking this integral removes the variations induced by manual experimentation. Each data point is the average of a number of measurements. Experiments performed with different samples yield similar responses. The response signal increases with increasing applied force. This demonstrates that this structure can be used as a force sensor. Alternatively, a touch sensor switch can be used to turn on a voltage and thus physically expand or contract the active tactile layer. An alternating voltage signal can be used to vibrate the stack at a preset frequency, sending a sensory signal back to the object touching the pad.

[0078] The foregoing detailed description has been provided by way of illustration and description and is not intended to limit the scope of the appended claims. Many variations of the presently preferred embodiments described herein will be apparent to those of ordinary skill in the art and remain within the scope of the appended claims and their equivalents.

Claims

1. A piezoelectric polymer; A composition comprising:

2. The composition of claim 1 , wherein the composition is for use in the manufacture of in-mold electronic (IME) components.

3. 3. The composition according to claim 1 or 2, in the form of an ink, preferably said ink being a conductive ink or a dielectric ink.

4. 3. The composition according to claim 1 or 2, in the form of a paste, preferably said paste being a conductive or dielectric paste.

5. The composition of any one of claims 1 to 4, wherein the piezoelectric polymer comprises polyvinylidene fluoride (PVDF).

6. The composition of claim 5, wherein the piezoelectric polymer comprises polyvinylidene fluoride-trifluoroethylene copolymer (PVDF-TrFe).

7. Based on the total weight of the composition, 5-95% by weight piezoelectric polymer, preferably 15-70% by weight piezoelectric polymer, more preferably 20-60% by weight piezoelectric polymer; 7. The composition according to any one of claims 1 to 6, comprising 5 to 95% by weight of binder, preferably 30 to 85% by weight of binder, more preferably 40 to 80% by weight of binder.

8. The binder is a thermoplastic resin containing a hydroxyl group; A cross-linking agent; The composition according to any one of claims 1 to 7, comprising:

9. The composition of claim 8 , wherein the thermoplastic resin has a glass transition temperature of less than 100° C. and / or a softening point of less than 100° C.

10. 10. The composition of claim 8 or 9, wherein the thermoplastic resin comprises one or more of a polyurethane resin, a polyester resin, a polyacrylate resin, a polyvinyl ester resin, a phenoxy resin, and a ketone resin.

11. The thermoplastic resin comprises, based on the total weight of the thermoplastic resin, 20 to 60% by weight of a polyurethane resin, preferably 35 to 47% by weight of a polyurethane resin; 5 to 30% by weight of a polyester resin, preferably 13 to 19% by weight of a polyester resin; The composition of claim 10, comprising 20-60% by weight of a phenoxy resin, preferably 34-51% by weight of a phenoxy resin.

12. The thermoplastic resin is and / or and / or has a glass transition temperature of less than 100° C. and / or has a weight average molecular weight of 1000 to 100000 g / mol; and / or has a softening point of less than 100°C; 12. The composition according to any one of claims 8 to 11, having a hydroxyl content (OH number) of more than 20 mg KOH / g.

13. The composition of any one of claims 8 to 12, wherein the crosslinking agent comprises one or more of a melamine resin, an amino resin, a polyamine resin, an isocyanate, and a polyisocyanate.

14. The composition of any one of claims 8 to 13, wherein the crosslinking agent comprises melamine formaldehyde.

15. 15. The composition of claim 14, wherein the melamine formaldehyde comprises hexamethoxymethylmelamine.

16. 16. The composition of claim 14 or 15, wherein the crosslinker further comprises an isocyanate, and / or a polyisocyanate, and / or a blocked polyisocyanate.

17. The composition of any one of claims 8 to 16, wherein the solvent comprises one or more of an alcohol, a glycol, a glycol ether, a glycol ester, an ester, a ketone, and a hydrocarbon.

18. The solvent comprises, based on the total weight of the solvent, up to 95% by weight of glycol ether acetate, preferably up to 85% by weight of glycol ether acetate, and / or up to 95% by weight of glycol ethers, preferably up to 85% by weight of glycol ethers, and / or up to 15% esters, preferably up to 5% by weight esters, and / or up to 40% by weight of ketones, preferably up to 32% by weight of ketones, and / or up to 80% by weight of alcohol, preferably up to 70% by weight of alcohol, and / or 18. The composition according to claim 17, comprising up to 30% by weight of hydrocarbons, preferably up to 22% by weight of hydrocarbons.

19. The binder comprises, based on the total weight of the binder, 10 to 40% by weight of said thermoplastic resin, preferably 11 to 30.4% by weight of said thermoplastic resin; 0.5-12 wt. % of said crosslinking agent, preferably 1.5-7.7 wt. % of said crosslinking agent; A composition according to any one of claims 8 to 18, comprising 40 to 85% by weight of a solvent, preferably 46.7 to 78.8% by weight of a solvent.

20. the binder is a thermosetting resin, preferably a thermosetting resin including one or both of an acrylic resin and an epoxy resin; 20. The composition according to any one of claims 8 to 19, further comprising a curing catalyst for curing the thermosetting resin, preferably for thermally curing the thermosetting resin and / or for UV curing the thermosetting resin.

21. 21. The composition of any one of claims 1 to 20, wherein the binder further comprises one or more functional additives, preferably selected from one or more of surfactants, rheology modifiers, dispersants, defoamers, anti-blocking agents, slip additives, anti-sagging agents, levelling agents, surface active agents, surface tension reducing agents, adhesion promoters, anti-skinning agents, matting agents, colourants, dyes, pigments and wetting agents.

22. The binder comprises, based on the total weight of the binder, 0.5-12 wt. % of said crosslinking agent, preferably 1.5-7.7 wt. % of said crosslinking agent; 10 to 40% by weight of said thermoplastic resin, preferably 11 to 30.4% by weight of said thermoplastic resin; 40-85% by weight of a solvent, preferably 46.7-78.8% by weight of a solvent, and optionally 0.1-30% by weight of a thermosetting resin and 0.1-3% by weight of a curing catalyst for curing said thermosetting resin, preferably 1-10% by weight of a thermosetting resin and 0.1-1% by weight of a curing catalyst for curing said thermosetting resin, and / or A composition according to any one of claims 1 to 21, comprising 0.1 to 20 wt. % of a functional additive, preferably 1.7 to 17 wt. % of a functional additive.

23. A method for producing a composition according to any one of claims 8 to 22, comprising the steps of: Providing a solvent; Providing a thermoplastic resin having a hydroxyl group; dissolving said thermoplastic resin in said solvent at a temperature of 50 to 100°C, preferably 70 to 100°C; Cooling the solution to room temperature; adding to the cooled solution a piezoelectric polymer, a crosslinker, and optionally one or more of a functional additive, a thermosetting resin, a curing catalyst for curing the thermosetting resin, conductive particles, and non-conductive particles.

24. 1. A method for manufacturing an in-mold electronic (IME) component, comprising: Preparing a blank; and thermoforming the blank. Preparing the blank includes forming one or more structures on a thermoformable substrate, each structure comprising: Disposing the composition of any one of claims 1 to 22 on a thermoformable substrate; and drying the composition at a temperature of 20-150° C. for 0.5-60 minutes.

25. 25. The method of claim 24, wherein the one or more structures include a haptic structure, preferably an audio speaker or a mechanical vibration device.

26. 26. The method of claim 24 or 25, wherein disposing the composition comprises printing the composition, preferably screen printing the composition.

27. 27. The method of any one of claims 24 to 26, wherein the substrate comprises one or more of polyethylene terephthalate (PET), polycarbonate (PC), paper, poly(methyl methacrylate) (PMMA), polyethylene nephalate (PEN), polyimide (PI), and thermoplastic polyurethane (TPU).

28. 28. The method of any one of claims 24 to 27, wherein the thermoforming is carried out at a temperature of from 140°C to 210°C and / or at a pressure of from 0.25 MPa to 0.4 MPa and / or at a pressure in the range of from 6 MPa to 12 MPa.

29. 29. The method of any one of claims 24 to 28, further comprising applying a layer of resin to the substrate using injection molding after thermoforming, preferably the resin comprises one or more of polycarbonate (PC), polyethylene terephthalate (PET), acrylonitrile butadiene styrene (ABS), polypropylene (PP), polyester, poly(methyl methacrylate) (PMMA), low density polyethylene (LDPE), high density polyethylene (HDPE), polystyrene (PS), and thermoplastic polyurethane (TPU).

30. The method of claim 29, wherein the injection molding is carried out at a temperature of from 170 to 330°C.

31. The method of any one of claims 24 to 30, wherein preparing the blank further comprises forming one or more conductive and / or dielectric layers on the substrate and / or structure.

32. The method of any one of claims 24 to 31, wherein the in-mold electronic (IME) component comprises a capacitive touch switch, a resistive touch switch, or a capacitive touch sensor.

33. The method of any one of claims 24 to 32, wherein the in-mold electronic (IME) components include one or more of a display, a light / lamp, a sensor, an indicator, and a haptic / touch feedback device.

34. An In-Mold Electronic (IME) component manufactured according to the method of any one of claims 24 to 33.

35. An in-mold electronic (IME) component comprising the composition of any one of claims 1 to 22.

36. In-mold electronic (IME) components including piezoelectric polymers.

37. An in-mold electronic (IME) component according to any one of claims 33 to 35, wherein the component comprises a tactile component.

38. A capacitive or resistive touch switch comprising an in-mold electronic (IME) component according to any one of claims 24 to 37.

39. 40. The capacitive or resistive touch switch of claim 38, wherein the tactile component is sandwiched between two electrodes, preferably one of the electrodes comprising a touch pad.

40. 40. The capacitive touch switch of claim 39, wherein the tactile component is a dielectric.

41. 40. The capacitive touch switch of claim 39, further comprising a dielectric layer positioned between the tactile component and each electrode.

42. 1. A method of forming a haptic component, comprising: Providing a substrate; disposing a composition according to any one of claims 1 to 22 on the substrate; and drying the composition at a temperature of from 20 to 150° C. for from 0.5 to 60 minutes.

43. A tactile component formed using the method of claim 42 or comprising the composition of any one of claims 1-22.

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