Multilayer structures for hosting electronic devices and related manufacturing methods - Patents.com

Abstract

To alleviate at least one or more of the disadvantages associated with existing solutions of integrated multilayer structures and electronic devices embedded therein.SOLUTION: An integrated multilayer structure (100) includes a first substrate film (102) having a first side (102A) and including an electrically substantially insulating material, preferably moldable and optionally thermoplastic, a plastic layer (112) molded onto and at least partially overlying the first side surface of the first substrate film, and a circuit (104, 106) that optionally includes an electronic component, an electromechanical component, and / or an electro-optical component, and is provided on the second side surface of the first substrate film and functionally connected to the first side surface of the first substrate film.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The project leading to this application has received funding from the European Union's Horizon 2020 research and innovation programme under agreement no. 725076.

[0002] Generally, the present invention relates to electronic devices, related devices, structures, and manufacturing methods. In particular, but not exclusively, the present invention relates to providing a unitary multi-layer structure incorporating multiple electronic components disposed on a substrate film, and a molding layer disposed on the film. [Background technology]

[0003] In the context of electronic devices and products in general, there are a variety of different laminate assemblies and structures.

[0004] The motivations behind integrating electronic devices and related products can be as diverse as the relevant use contexts. More often than not, the resulting solution ultimately exhibits a multi-layered nature, driven by a desire for miniaturization, weight reduction, material savings, cost savings, performance improvement, or simply efficient component packing. Related use scenarios, in turn, can relate to product packaging or food casings, visual design of device housings, wearable electronics, personal electronic devices, displays, detectors or sensors, vehicle interiors, antennas, labels, vehicle electronics, etc.

[0005] Electronic devices, such as electronic components, integrated circuits (ICs), and conductors, can generally be provided on substrate elements by several different techniques. For example, prefabricated electronic devices, such as various surface-mounted devices (SMDs), may be mounted on substrate surfaces that ultimately form the inner or outer interface layers of multilayer structures. Additionally, technologies falling under the term "printed electronics" may be applied directly and essentially additively to the associated substrate to actually create electronic devices. The term "printed" in this context refers to various printing techniques that can create electronic devices / electrical elements from printed matter through a substantially additive printing process. Printing techniques include, but are not limited to, screen printing, flexography, and inkjet printing. The substrates used may be flexible, and the printing materials may be organic, but this is not always the case.

[0006] The substrate may be provided with electronics and overmolded with plastic to create a multi-layer structure in which the electronics are at least partially embedded in the molding layer. Thus, the electronics may be hidden from the environment and protected from environmental conditions such as moisture, physical impact, or dust. However, the molding layer may also have various additional uses in terms of aesthetics, transfer medium, dimensional design, etc.

[0007] However, even when various electronic devices are mounted in a multi-layer structure, they still do not necessarily function completely separately, i.e., autonomously. Instead, various external power, data, and / or control connections may have to be provided thereto, typically requiring the provision of electrical connectors and associated wiring, even if wireless connections are also applicable. In certain scenarios, when the target component is located deep within the multi-layer structure, creating the required physical connections and the layout of the connections themselves may prove to be quite complex.

[0008] Furthermore, the high level of integration resulting from embedding electronics within multi-layer structures, and the thermal insulating properties of, for example, the associated material layers, may raise concerns regarding associated thermal management, as encapsulated components may easily overheat due to their reduced cooling, e.g., convection.

[0009] It should be noted that in certain scenarios, the nature of the electronics utilized in conjunction with the multi-layer structure, e.g., with respect to light emitting components, may be such that they can easily interfere with the function or degrade the appearance of the entire structure and / or other embedded elements, considering, for example, light leakage in the context of the light emitting components discussed above. Correspondingly, the inclusion of certain electronics within the multi-layer structure may prevent the electronics from functioning in an optimal or even sufficient manner due to interference caused by other adjacent or nearby components or materials.

[0010] Furthermore, some electronic components incorporate moving parts that use electricity to produce mechanical motion, or vice versa, for example with respect to electromechanical devices. Thus, embedding such elements within a multi-layer structure, for example within a layer of solid material, can clearly hinder the operation of the component, or one must take cumbersome measures, for example to provide the necessary internal cavities within the structure to allow sufficient movement of the internal moving part(s).

[0011] Furthermore, in some applications, components such as sensors that require interaction with the environment, such as measuring relevant properties, simply cannot be located within, for example, a closed structure, in order to properly perform their intended function.

[0012] After all, some components may require very complex layouts or generally large spaces or surface areas, and in many usage scenarios and contexts, including them as embedded components sandwiched between layers of material is not particularly feasible. Summary of the Invention

[0013] It is an object of the present invention to at least mitigate one or more of the above-mentioned drawbacks associated with existing solutions in the context of integrated multi-layer structures and electronic devices embedded therein.

[0014] The above objects are achieved by various embodiments of the multilayer structure and associated manufacturing method according to the present invention.Furthermore, a substrate for use in the multilayer structure and associated manufacturing method is presented.

[0015] According to one embodiment of the present invention, the integral multi-layer structure comprises: a first substrate film having a first side and an opposing second side, the first substrate film comprising an electrically substantially insulating material, preferably moldable and / or thermoplastic; a plastic layer, such as a thermoplastic or thermosetting plastic layer, molded on the first side of the first substrate film so as to at least partially cover the first side; a circuit provided on the second surface of the first substrate film, the circuit preferably including at least one electronic, electromechanical, and / or electro-optical component, the circuit operatively connected to the first surface of the substrate film; Includes:

[0016] In various embodiments, a second (substrate) film may be provided on the opposite side of the molded plastic. From the perspective of typical, but not exclusive, possible usage scenarios for the multilayer structure, the first side of the first film can be considered to face the front side of the structure, and as a result, the first side of the first film is also configured to face the user and / or environment of the structure and its host device. Furthermore, the desired second film, when included in the structure, can be considered the front side film of the structure, closer to the user / environment / host device from the perspective of the user / environment / host device. Meanwhile, the first film can correspondingly be considered the back side film. However, those skilled in the art should be aware that in some other embodiments, orientation issues such as "front side" or "back side" may not play a similar role (e.g., when the structure is completely embedded in the host device / host structure), or that the structure may simply be aligned differently than in the above scenario. The first and second films may be similar to or different from each other in terms of their dimensions, materials, shapes, vias, and / or other features, such as components or generally hosted circuits.

[0017] Similarly, the second film may function (as the first film) as a substrate for various features, including, for example, graphics and / or electronics provided on the first and / or second surfaces thereof, electronic components optionally mounted and / or printed thereon, and / or traces, conductors, contact pads, masking, cooling / thermal control, or insulating elements. Thus, the second film faces the molding layer from the opposite direction from the first, i.e., first, substrate film. The second film may be placed, i.e., inserted, into a mold together with the first film, and a plastic material may be injected between them. Alternatively, the second film may be laminated onto the molding layer by any lamination technique possible, for example, using adhesive, high temperature, and / or pressure-based bonding. In some embodiments, the second film is electrically connected to the first film by providing a conductive material between them. Additionally or alternatively, the film or features thereon may be wirelessly connected electrically or electromagnetically to each other and to an external element, such as a user's hand, finger, or (other) stylus, by associated electromagnetic fields or fluxes.

[0018] In various embodiments, the first and, optionally, second substrate films may comprise or consist of several materials, such as organic or biological materials, such as wood, leather, or fabrics (e.g., cotton-, wool-, silk-, or flax-based), or any combination of these materials with each other and / or with plastics, polymers, or metals. The films may generally be comprised of, or at least include, other formable materials, such as thermoplastic or thermoformable materials. Furthermore, the film material may be, at least locally, substantially electrically insulating, e.g., a dielectric. In some other embodiments, the material may be, at least locally, conductive. In some embodiments, the second film may be comprised of a conductive material (e.g., metal) and / or an insulating material (e.g., most plastics) deeper in the structure, e.g., to control (direct, attenuate (shield), strengthen, etc.) the characteristics of an external electric field.

[0019] Generally, in various embodiments, on any side of the molded layer, there may actually be one or more similar or different (substrate) films and / or other material layers, which may or may not include circuitry such as electronic components, traces, contact pads, shielding elements, graphics (e.g., ink- or paint-based colored shape-formed embedded microstructures, or optical, e.g., refractive and / or diffractive embedded microstructures), cooling or thermoelectric elements, and / or other features. In various embodiments, the graphics or graphics layer may be provided within the structure, for example, by utilizing IML technology, in which a film with graphics provided thereon is used as an insert in a mold and then overmolded so that the graphics face the molded plastic, sandwiching the graphics between the film material and the molded plastic.

[0020] One or more of the included films may be at least partially, i.e., at least in places, optically substantially opaque or translucent, e.g., with respect to predetermined wavelengths in the visible spectrum. For example, in connection with including light-emitting and light-capturing (e.g., sensing) components, respectively, the wavelengths may include wavelengths emitted or received by the electronics of the multilayer structure. The film(s) may initially be provided with visually discernible, decorative / aesthetic, and / or informational features such as graphics (e.g., signs, symbols, indicia, icons, diagrams, numbers, letters, writing, drawings, geometric designs, and / or patterns) and / or color generally thereon or therein. Features such as graphics or general optical shapes may be provided additively, e.g., by coating or printing, and / or via subtractive methods such as engraving, perforating, embossing, or generally thinning. A film or other element that is considered substantially transparent may have a transmittance of, for example, about 80%, 85%, 90%, 95%, or greater than 95%, taking into account the wavelengths of interest.

[0021] In some embodiments, selected structural features, preferably embedded graphics, or for example, selected regions or volumes thereof, may be illuminated by underlying light emitting elements and / or they may be highly reflective of external light, such as ambient light or other light incident thereon. For example, illumination may be utilized to enhance their visibility. The reflection may be diffuse and / or specular.

[0022] In some embodiments, on the other hand, a region or volume of a substantially opaque (e.g., colored) or translucent structure (film, other material layer, or feature) may be configured to optically mask a selected underlying structure, e.g., from external viewing, e.g., with respect to visible light and / or other wavelengths. Thus, the film or other layer may actually have desired optical properties with respect to presented color, texture, transmittance (opaque, translucent, transparent), etc., with respect to the target wavelengths, etc.

[0023] Multiple films and / or other layers on either side of the molded plastic layer may be attached together via lamination (heat, pressure, adhesives, etc.) and / or by mechanical fastening means such as rivets, screws, or bolts. The films may be flexible (reversibly bendable), or essentially inflexible, or rigid (plastically deformable).

[0024] In various embodiments, the first film and / or second film(s) may exhibit planar shapes in the structure, however, the shapes involved may alternatively be at least locally three-dimensional in nature and may be constructed by forming, such as by thermoforming or cold forming, as described in more detail below.

[0025] In various embodiments, the first film and / or the second film may include one or more through-film features, such as vias, that typically extend through the thickness of the film.

[0026] Preferably, the vias are provided with or essentially filled with a conductive material. It is further preferred that the conductive material be formable, taking into account their desired properties, such as conductivity, so as to survive (thermo)forming of the host film, for example, at least without undue fracture. Via(s) may be provided in the forming layer and / or other material layers of the multi-layer structure for the same or different purposes. For example, optical or electromagnetic vias may be provided in various layers of the structure.

[0027] In various embodiments, selected features provided on the film(s), such as traces, contact pads, electrodes and / or other types of conductors or generally conductive elements, or components, or generally circuits, may be or include portions that are at least optically opaque, translucent, or substantially transparent (clear) given a selected wavelength, e.g., visible light, or operating frequency, including, e.g., light emitting or light detecting components.

[0028] In various embodiments, for example, printed conductors, electrodes, and / or any other conductive elements or shapes disposed on the structure may have cutouts or interior portions that generally do not include opaque material, allowing light to pass through, for example, from underlying light sources and / or light guides. Thus, different features, such as visual indicators (e.g., icons) and / or control input elements (e.g., touch sensors), may be illuminated by the backlight. For example, light directing means, such as light sources and / or associated light guides, may be disposed on the second side of the first substrate film to direct light toward their first side. Meanwhile, cutout elements, such as conductors, may be disposed on the first side, allowing light to propagate through them and through the cutouts.

[0029] In various embodiments, the circuitry includes at least one component selected from the group consisting of electronic components, electro-optical components, electromechanical components, radiation-emitting components, light-emitting components, LEDs (light emitting diodes), OLEDs (organic LEDs), radiation-detecting components, light-detecting components, photodiodes, phototransistors, photovoltaic devices such as cells, sensors, air sensors, gas sensors, temperature sensors, humidity sensors, micromechanical components (e.g., on the second side of the first substrate film, as will be understood by those skilled in the art), switches, contact switches, proximity switches, contact sensors, proximity sensors, capacitive switches, capacitive sensors, projected capacitive sensors or switches, single-electrode capacitive switches or sensors, multi-pole capacitive switches or sensors, self-capacitance sensors, mutual capacitance sensors, inductive sensors, sensor electrodes, UI elements, user input elements, vibration elements (e.g., on the second side of the first substrate film), communication elements, data processing elements, and data storage elements. Note that, for example, an electronic subassembly comprising a circuit board and its component(s) may be provided on the substrate(s) and / or other layers of the structure.

[0030] In various embodiments, the multilayer structure includes at least one optically transmissive element, such as a light guide, or in particular a light guide, configured, e.g., with respect to dimensions, materials (e.g., associated refractive index, transmittance), etc., to transmit and direct the incoupled light in a desired manner. The light guide, for example, can direct the incoupled light in a selected direction, outcouple the incoupled light through a selected exit surface thereof, or direct the incoupled light to, for example, a photosensitive sensor or other optically functional element disposed therein and adjacent to or at least optically coupled to the light guide.

[0031] The light guide may be mounted or constructed, for example, on the second side of the first substrate film. The light guide may be pre-prepared, e.g., (3D) formed, or may further be applied in a mold, e.g., as a spacer and / or barrier on the film, to protect other elements, such as LEDs, or other light sources or their associated circuitry, from excessive pressure, e.g., caused by the mold. Instead of or in addition to the light guide, other suitable elements may be used as similar spacers or barriers to protect the circuitry before, during, and / or after molding the plastic layer. For example, the light guide / barrier may be provided with holes to accommodate elements, such as LEDs. After placing the elements in the holes, the space remaining in the holes may be filled with a further protective material (e.g., a suitable plastic or resin).

[0032] Similarly, in various embodiments, the first side and associated first surface of, for example, the first substrate film may also be provided with, for example, electronic components, optoelectronic components (e.g., LEDs), electromechanical components, traces, contact pads, electrodes, light guides, multi-component devices or configurations, sensors, switches, etc., such as any one or more of the features described above.

[0033] In various embodiments, the structure further comprises a second molding layer disposed on the second side, optionally at least locally in contact with the associated second surface of the first substrate film, the material of which may be the same as or different from the material of the first molding layer on the opposite first side.

[0034] If desired, multi-material molding techniques such as multi-shot molding can be used to provide several plastic layers in one process and may be applied to fabricate selected molding layer(s) of the multi-layer structures proposed herein.

[0035] In general, in various embodiments, the plastic layer(s) molded onto any film included in the multilayer structure may include materials such as polymers, organic materials, biomaterials, composite materials such as organic materials or graphite, and any feasible combination thereof. The material(s) may be or at least include a thermoplastic material. Alternatively or additionally, the molded layer(s) may be composed of or at least include a thermosetting material.

[0036] The first side, and therefore the associated first surface of the substrate film, is actually at least partially overmolded with a plastic, such as a thermoplastic or thermosetting material, given the associated surface area. The molding techniques used may vary between embodiments and may include, for example, injection molding and reaction molding, such as reaction injection molding. The molding process may be of the multi-material type described above and / or multi-shot type, as needed. Low-pressure molding may be applied to prevent underlying electronics from being damaged, for example, by excessive pressure. Similar considerations generally apply to the second side and associated surfaces, which may have been at least partially subjected to molding, such as low-pressure molding, to cover and protect the underlying circuitry. If desired, several molding materials may be utilized to construct one or more molding layers, e.g., adjacent layers. The adjacent layers form a stack of multiple superimposed layers on the left and right sides of and / or above the first and / or second side of the substrate. One or more components and / or other circuits may be constructed (e.g., printed), mounted, or otherwise provided on any side surface of the substrate film, but may also be at least partially overmolded by an applied molding procedure.

[0037] In some embodiments, the material(s) used to construct the shaping layer(s) may include optically substantially opaque, transparent, and / or translucent materials. Transparent or translucent materials may be utilized to allow other selected wavelengths, such as visible light or electromagnetic radiation, to pass therethrough with negligible loss. A transmittance sufficient to provide substantial transparency at a desired wavelength may be, for example, about 70%, 75%, 80%, 85%, 90%, or 95%, or even greater than 95%, depending on the embodiment.

[0038] Additionally, systems may be provided that include embodiments of the multi-layer structure and embodiments of an optional host structure or device that houses or at least functionally connects the multi-layer structure.

[0039] Optionally, the host structure or device functionally and / or physically (e.g., mechanically) connected to an embodiment of a multi-layer structure according to the present invention may comprise at least one element selected from the group consisting of an electronic terminal device, a portable terminal device, a personal digital assistant device or controller, a personal electronic device, a vehicle, a car, a truck, an airplane, a helicopter, an on-board electronic device, a vehicle dashboard, a vehicle exterior, a vehicle interior element, a vehicle interior panel, a vehicle lighting device, a measuring device, a computing device, an intelligent garment (e.g., a shirt, jacket, or pants, or, for example, a compression garment), other pieces of wearable electronics (e.g., a wrist-top device, a hat, or footwear), a multimedia device or player, an industrial machine, a controller device, a personal communication device (e.g., a smartphone, a phablet, or a tablet), or other electronic device.

[0040] According to another embodiment of the present invention, a method for producing a multi-layer structure includes: a first substrate film for housing an electronic device, the first substrate film having a first side surface, optionally facing a predetermined front side of a structure, the first side surface of the first substrate film preferably configured to face a user and / or a use environment of the structure or a use environment of a host device of the structure, and an opposing second side surface, the first substrate film comprising an electrically substantially insulating material, the first substrate film preferably being moldable and / or thermoplastic; providing, optionally by packaging and / or by printed electronics techniques, circuitry on at least said second surface of the first substrate film, said circuitry being operatively connected to the first surface of the first substrate film; and, Molding a plastic material onto a surface of the first side of the first substrate film so as to at least partially cover it.

[0041] As mentioned above, in some embodiments, additional (substrate) films and / or other material layers may be provided within the structure, used in the molding procedure, for example as inserts, laminated onto existing layers, or built directly into the structure, for example by molding or printing.

[0042] Thus, for example, a second film may be applied to the other side of the molded plastic, as described above, if desired. The second film may be placed in a mold together with the first substrate and plastic material injected between them to obtain a laminated structure, or if the second film is not manufactured directly on the molded plastic layer, it may be applied later using a suitable lamination technique. The second film may also be provided with electronics and, for example, graphics (e.g., IML technology may be applied) on any side thereof (e.g., facing the molded plastic layer). Furthermore, it may have other technical properties, such as protective purposes and / or a desired light transmittance, appearance (e.g., color), or feel.

[0043] Possible molding methods include, for example, injection molding in connection with thermoplastic materials, and reaction molding, such as reaction injection molding, particularly in connection with thermosets. In the case of some plastic materials, they may be molded using two-shot or, more generally, multi-shot molding methods. Molding machines with multiple molding units may be utilized. Alternatively, several machines or a single reconfigurable machine may be used to feed several materials sequentially.

[0044] Considering applicable molding techniques and parameters, for example, the injection molding and reaction molding described above are practically viable options depending on the materials used, desired material properties, molding equipment, etc. To minimize stress on underlying features such as electronics, low-pressure (e.g., less than about 10 bar) molding may be used in selected molding operations, such as overmolding the second side surface of the first substrate and the circuitry thereon. For example, different molding techniques may be applied to impart different material properties to the structure in terms of desired mechanical properties such as strength.

[0045] In various embodiments, one or more substrate films, preferably after providing circuitry such as numerous components, electrodes, conductors, and / or contact pads thereon, are formed, and optionally thermoformed, to exhibit a desired target shape that is not substantially flat but is typically at least locally three-dimensional (3D). The materials, dimensions, placement, and other configurations of elements such as electronics already present on the film prior to forming should be selected to withstand the forces induced therein by forming without breaking.

[0046] In various embodiments, certain features, such as traces, contact pads, additional conductive elements, other circuitry such as auxiliary components, light guides, and / or graphics or graphics layers, may be applied to the multilayer structure, if desired, by printed electronics techniques such as screen printing or inkjet printing, packaging, deposition, lamination, and / or other applicable technique(s). For example, traces may be printed onto the substrate film to connect components. As will be appreciated by those skilled in the art, it may often be more practical to apply, for example, traces and contact pads before fabricating or mounting components thereon.

[0047] In various embodiments, several vias may be constructed in the film(s), for example to electrically connect their first and second side surfaces together, in effect, for example to associate together electronics on both sides of the associated film.

[0048] Generally, vias, or generally through-holes, in the film(s) and / or other layers of the structure may be provided by molding (or generally by directly constructing the substrate film with holes), chemically drilling (e.g., by etching), engraving, sawing, etching, cutting (e.g., with a laser or mechanical blade), or using any other feasible method as would be understood by one skilled in the art. The vias may have any desired cross-sectional shape, i.e., substantially circular or polygonal, e.g., rectangular or elongated (slit) shape.

[0049] The vias may comprise selected material(s), such as conductive and / or optically transparent materials, using a selected filling method, such as molding, packaging, or printing. The materials may include adhesives, epoxies, metals, conductive inks, etc. The materials may be formable, for example, to withstand bending strain.

[0050] In various embodiments, the film(s) and / or other layers may also have a number of blind holes or thinned portions formed therein by engraving, molding, drilling, etc. Such holes may be configured to construct or contain, for example, electronic components, conductive or insulating elements, graphics, or fluids (e.g., liquids and / or gases).

[0051] It should be noted that in various embodiments of the present methods, the second side and associated second surface of the first substrate film may also be at least partially overmolded with at least one material, for example, as previously discussed, low pressure molding may be used to protect underlying elements such as components or other circuitry.

[0052] The electronics provided in the multi-layer structure may have purposes such as control, measurement, UI, data processing, storage, etc., as described elsewhere herein.

[0053] The order in which the various method steps are performed relative to one another may vary depending on the particular embodiment and may be determined on a case-specific basis. For example, the second side of the first substrate film may be overmolded before, after, or substantially simultaneously with the first side. For example, molding material may be injected from the first side of the film to the opposite side, e.g., through holes present therein or induced by pressure, so as to extend therefrom.

[0054] As will be appreciated by those skilled in the art, the considerations presented above with respect to various embodiments of the multi-layer structure may be flexibly applied, mutatis mutandis, to embodiments of the related manufacturing methods, and vice versa. Furthermore, the various embodiments and related features may be flexibly combined by those skilled in the art to come up with preferred combinations of features generally disclosed herein.

[0055] Additionally, in further embodiments of many of the aspects described above, a substrate film may be provided for hosting, for example, the circuits and / or other features described above. The substrate film may include or consist essentially of a moldable, optionally thermoformable, thermoformable material, such as a thermoplastic or thermosetting material. The substrate film may further include at least one via, or element of such material, that is moldable and preferably filled with a conductive material, to electrically couple the opposing first and second sides (and thus the respective surfaces) of the film to one another.

[0056] The film and via(s) may generally have the properties mentioned above. The film may be substantially planar or, at least locally, substantially three-dimensional after forming, such as by a thermoforming or cold-forming procedure. Furthermore, the film may be provided on any of its lateral surfaces with electronics, such as various components, traces, pads, electrodes, etc., whereby via(s) may be arranged to electrically and therefore operatively interconnect the same. Note that the via(s), or vias in general, may additionally or alternatively be filled with, for example, an optically transparent material, which may also be electrically conductive or insulating. The filling material of the via(s) preferably withstands both the forming and (over)molding, which may optionally be performed on the film after providing at least one via and its associated filling material.

[0057] Additionally, methods of manufacturing embodiments of the above substrate films may be provided in which vias are created, for example by molding or drilling, and subsequently filled with a selected, preferably conductive, material, such as a conductive (e.g., silver) ink, via printing or other suitable filling method. In some embodiments, the construction and filling of the vias may be combined into a single step.

[0058] The above substrate films and associated manufacturing methods may, of course, form part of the previously described multilayer structures or associated manufacturing method embodiments, respectively, but the films and associated methods may also find independent use in other usage scenarios and contexts, as will be readily understood by those skilled in the art.

[0059] The usefulness of the present invention arises from several issues depending on the embodiment.

[0060] In many use scenarios, by placing electronic components and possibly other features, such as associated traces, pads, electrodes, or optical components, on the second side, or "back" side, of the substrate film (the opposing first side, or "front" side, is overmolded with a plastic material and faces the user / structure's environment), various concerns about component thermal management can be significantly alleviated. In fact, for example, the risk of overheating can be reduced in high power and similar applications, which are often associated with significant heat loads. Furthermore, options for sophisticated thermal control of features are improved.

[0061] Additionally, because the second side of the substrate film may also define the (inner) outer surface, or at least be closer to the surface of the multilayer structure, by placing components on the second side of the substrate film, it may be easier to establish connections to external elements, such as a host device or host structure. Also, connections between components on the second side may be easier to mount to one another if the components and support surfaces for connection elements, such as traces, are closer to the structure's exterior, improving their accessibility.

[0062] In some embodiments, components that, when placed on the first side of the substrate film and optionally embedded in plastic, may interfere with the function of other components or the function of the multilayer structure in general, for example in connection with electrical noise or optical interference such as light leakage to nearby components or layers, can be placed on the second side to avoid or at least reduce the detrimental effects of the components, for example, the substrate film can act as an additional shielding or barrier layer in such cases.

[0063] In some embodiments, sensitive components, such as various sensing electronics, may not function properly if placed too close to other components on the first side of the substrate, but may function perfectly well if placed on the second side. Similarly, certain electronics, such as air sensors, may require direct exposure to the ambient medium, such as air, that they are to be measured. In this case, they should not be embedded in the plastic on the first side of the substrate, but instead should be located on the second side without any layers that would interfere with the measurement.

[0064] In some embodiments, moving parts or parts incorporating moving parts(s) may be avoided from being placed on the second side of the substrate film, for example, by limiting the influence of overmolded plastic or other closely adjacent layers on the first side, which would prevent them from functioning properly.

[0065] In some embodiments, it may be more practical to place components that have particularly complex layouts or generally require large spaces or surface areas on the outside of the substrate film, and thus potentially the entire multilayer structure, i.e., on the second side and associated surfaces.

[0066] The proposed manufacturing method applying overmolding is relatively simple to adopt, and what is considered to be a further advantage is that it does not require the development of entirely new or particularly complex manufacturing techniques, for example when relying on printed electronics and in-mold electronics. The need for tedious 3D assembly and other 3D-intensive processing of electronics on a substrate can be further reduced or eliminated by (thermo)forming the film(s) into the desired 3D shape while the substrate film is still substantially flat after providing the electronics, vias, and e.g., conductors thereon.

[0067] In general, the resulting multilayer structures may be used to construct desired devices, or modules of, for example, host devices or host structures, such as intelligent clothing (e.g., shirts, jackets, or pants, or, for example, compression garments), other pieces of wearable electronics (e.g., wrist-top devices, hats, or footwear), vehicles, such as vehicle exteriors or vehicle interiors (e.g., on-board electronics), personal communication devices (e.g., smartphones, phablets, or tablets), or other electronic devices described herein. The resulting structures may have high integration levels and small desired dimensions, such as their thickness.

[0068] The film(s) used may be configured to have graphics and other visually and / or tactilely detectable features thereon, where the film(s) may have aesthetic and / or informational value in addition to hosting and protecting the electronics. The film(s) may be translucent or opaque, at least in places. The film(s) may exhibit a desired color.

[0069] The resulting multilayer structure may therefore generally incorporate one or more color / pigment layers, if desired, that define graphics such as text, images, symbols, patterns, etc. These layers may be implemented, for example, by dedicated films of specific color(s), or may be provided as coatings (e.g., by printing) on existing film(s), shaping layer(s), and / or other surfaces.

[0070] The film(s) and / or shaping layer may be configured to construct at least a portion of the exterior and / or interior surfaces of an associated host device or other coupled structure.

[0071] Visual features such as patterns or coloring may be provided via an internal layer, for example on the side of the first film and / or possibly the second film facing the molded plastic, so that these features remain separated by at least the thickness of the film and thus protected from environmental influences, and therefore do not normally reach them due to various impacts, friction, chemicals, etc. that can easily damage, for example, applied surface features.

[0072] The film(s) can be easily fabricated or processed into desired shapes and cut as desired with required features, such as holes or cuts, to expose underlying features, such as molding compounds, and / or to create, for example, electrically or optically conductive vias.

[0073] The molded plastic material(s) may be optimized for various purposes, including securing the electronics, in terms of the molding process. Additionally, the material may be configured to protect the electronics from environmental conditions, such as moisture, heat, cold, dust, impact, etc. The material may also have desired properties, such as light transmittance and / or elasticity. If the embedded electronics include components that emit or receive light or other radiation, the material may have sufficient transmittance, for example, to allow light transmission therethrough. The molded material may initially exhibit some color or may be subsequently colored, for example, with ink, paint, or film coating.

[0074] The expression "a number of" as used herein may mean any positive integer starting from 1.

[0075] The expression "plurality" may mean any positive integer starting from 2, respectively.

[0076] The terms "first" and "second" are used herein to distinguish one element from another, and do not dictate any particular priority or order therebetween, unless expressly stated otherwise.

[0077] Different embodiments of the invention are set out in the accompanying dependent claims. [Brief explanation of the drawings]

[0078] The invention will now be described in more detail with reference to the accompanying drawings. [Figure 1] 1 illustrates one embodiment of a multi-layer structure according to the present invention and a possible associated environment of use. [Figure 2] 1 illustrates another multi-layer structure embodiment. [Figure 3] 10 illustrates a further multilayer structure embodiment. [Figure 4] 10 illustrates yet another multi-layer structure embodiment. [Figure 5] 10 illustrates yet another multi-layer structure embodiment. [Figure 6] 10 illustrates a further multilayer structure embodiment. [Figure 7] 10 illustrates a further multilayer structure embodiment. [Figure 8] 1 is a flow diagram disclosing an embodiment of a method according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0079] 1 illustrates in a cross-sectional side view many of the general concepts of various embodiments of the present invention through one merely exemplary realization of a multi-layer structure at 100. Item 101 represents the possible environment of use of structure 100 (outdoors, indoors, in a vehicle, etc.) and human user (if any) located within the environment, while item 110, indicated by a dashed outline, represents the host device or host structure 110.

[0080] The completed multi-layer structure 100 may actually construct its own final product, such as an electronic device, or may be placed in a host device as an integrated component or module. Item 100 may, of course, include several additional elements or layers not shown.

[0081] The structure 100 includes at least one substrate film 102 housing several electronic components 104 on its second side 102B (thus, the second side 102B is considered the outer back side in many, if not all, possible use cases, where the first or “front” side 102A can be considered to face the intended use environment and user 101). Thus, as shown, the second side 102A may face a possible host device or host structure 110, possibly be integrated therewith, or at least partially embedded therein. Alternatively, the second side 102A may face substantially opposite the first side 102A, e.g., facing the environment. For example, circuitry, including several components 104, may be directly fabricated, e.g., printed, by printed electronics techniques such as screen printing, pad printing, flexography, or inkjet printing, if desired.

[0082] Components 104 provided on second side surface 102B may be configured to detect user actions (e.g., touch or proximity / contactless input), or events or characteristics of environment 101, such as, for example, lighting conditions, or other optical or electrical / electromagnetic characteristics, or each may be configured to emit, for example, light or other forms of radiation into environment 101, such that components 104 are preferably functionally or "operably" connected to first side surface 102A, often to environment 101. Additionally, components 104 on both sides and associated surfaces of film 102 may be connected to each other, for example, optically or electrically, for various reasons, such as signaling (communication) or power transfer. Functional connections (e.g., electrical, optical, and / or electromagnetic) referred to herein may be direct or indirect, i.e., with or without intermediate components or elements.

[0083] The circuitry may include several additional elements 106 on the second side 102B, such as conductive contact pads or traces (conductors), optionally provided by printed electronics techniques, to provide electrical connections to and / or between components 104. At least some of the elements 106 may be at least locally disposed between the film surface and the associated component(s) 104. For example, a "contact pad" herein may refer to any conductive element or patch, or point or area of electrical connection on the substrate film. The contact pads as well as other conductors or traces may include or be made of conductive material(s), such as silver, aluminum, or a conductive elastomer containing, for example, carbon or other conductive particles, or other similar materials that can optionally enhance the visual quality of the surface on which the pad resides. The shape of the contact pad may be any suitable geometric shape.

[0084] In addition to or instead of a printed version, the component 104 may comprise a pre-fabricated component (surface) mounted to the substrate 102, such as a so-called surface-mounted device. For example, adhesives may be used to mechanically secure the electronics onto the substrate. Additional conductive material(s), such as conductive adhesives and / or solder, may be applied to establish electrical and mechanical connections between various elements, such as the conductor traces 106, and the component 104.

[0085] Thus, as discussed above, components 104 may include passive components, active components, ICs (integrated circuits), printed components such as screen printing, and / or electronic subassemblies. For example, one or more components may first be provided on a separate substrate, such as an FPC (flexible printed circuit) or a circuit board, such as a rigid, e.g., FR4 type (flame retardant) board, and then attached as a whole (i.e., as a subassembly) to the target substrate 102.

[0086] As previously mentioned, instead of or in addition to possible mechanical fastening, structure 100, and in particular electronics 104, 106 integrated therewith, may be operably connected wirelessly (e.g., by optical, ultrasonic, radio frequency, capacitive or inductive coupling, etc.) and / or by wire to an external element, such as a host device or host structure 110. In the latter case, suitable connection elements 105, such as electrical or optical wiring, connectors, cables, etc., may be utilized. For example, the external connection(s) may be conveniently implemented on second surface 102B of film 102.

[0087] In various embodiments, the connection element 105 may include a circuit board, such as a flex or rigid (e.g., FR4) type printed circuit board, as desired. In various embodiments, the connection element 105 may include at least one electronic component, such as a transistor or an integrated circuit (IC), e.g., an operational amplifier (although it may of course also be assembled from discrete components).

[0088] Thus, the connection elements 105 may be configured to accommodate components that are more difficult or virtually impossible to mount or fabricate on, for example, film-type substrates, which are typically quite thin and flexible. The connection elements 105 may be fixed to the substrate film 102 using, for example, glue, paste, conductive adhesive, mechanical fastening means, etc. For example, the electrical connection between the actual circuit design on the substrate film 102 and the connection elements 105 may be implemented by the same or dedicated mechanisms, such as, for example, solder, conductive adhesive or paste, traces, contact areas / contact pads, pins, flex cables, and / or elements of anisotropic material taking into account electrical conductivity, optionally ACF (Anisotropic Conductive Film).

[0089] Returning to component 104, which is preferably at least partially electronic or electrical in nature, component 104 may include at least one electronic element selected from the group consisting of an optoelectronic component, a microcontroller, a microprocessor, a signal processor, a DSP (digital signal processor), a sensor, a switch, a contact switch, a proximity switch, a programmable logic chip, a memory, a transistor, a resistor, a capacitor, an inductor, a capacitive switch, an electrode element, a memory array, a memory chip, a data interface, a transceiver, a wireless transceiver, a transmitter, a receiver, a wireless transmitter, and a wireless receiver, among other options.

[0090] It should be noted that the component 104 hosted by the structure 100 may include at least one optoelectronic component. The at least one optoelectronic component may include, for example, an LED (light-emitting diode), an OLED (organic LED), or some other light-emitting component. The light-emitting component may be side-emitting ("side-shooting" or "side-firing"), bottom-emitting, or top-emitting. Alternatively or additionally, the component 104 may include a light-receiving or light-sensitive component, such as a photodiode, photoresistor, other photodetector, or, for example, a photovoltaic cell. Instead of being mounted on the substrate film 102, the optoelectronic component, such as an OLED, may be printed onto the substrate film 102 using a preferred printed electronics technology method. Indeed, different sensing and / or other functions may be implemented, for example, by embedded ICs, dedicated components, shared ICs / electronics (multi-purpose electronics), and / or other circuitry. The substrate film 102 and the electronic devices 104, 106 on the substrate film 102 may be configured to create a desired circuit design.

[0091] The molded plastic layer 112 is disposed on at least the first surface 102A of the film 102. There may be additional components 104 and other features (such as light guides, graphic features, traces, contact pads, etc.) disposed on the first surface 102A and associated surfaces of the film 102. Thus, the components 104, other circuitry, and / or additional features on the first surface 102A may be at least partially embedded in the molding material 104. In some embodiments, as also described below, the second surface 102B of the film 102 may also be at least partially overmolded, as desired, to at least partially embed one or more components 104 and / or other features 106 (e.g., traces, contact pads, electrodes, heat sinks, or other cooling / thermoelectric elements) in the molding material. The molding techniques and parameters used may differ between the two surfaces 102A, 102B. To avoid causing pressure or heat damage to the components 104, for example, low pressure molding (e.g., preferably less than about 15 bar, more preferably less than about 10 bar) may be utilized to embed them. High pressure molding may also be subsequently applied to introduce additional layers into the laminate structure 100, if desired.

[0092] An optional second film 103, having the same or different material(s) as the first film 102, may likewise be present within the multi-layer stack. The film 103 may also house electronics 104, graphics and / or other features that may be beneficial on and within the second side (as shown) and / or first side (the outside, possibly the side directly facing and in contact with the environment 101) and their surfaces.

[0093] Additional films and / or other material layers 108, such as graphics or colored films or layers, coatings, etc., may be applied to either side of any of the films 102, 103 as desired, for example, aesthetic, protective / insulating, electrical and / or other purposes.

[0094] In terms of material selection, the film(s) 102, 103 may consist essentially of or include at least one material selected from the group consisting of polymers, thermoplastics, copolyesters, PMMA (polymethyl methacrylate), polycarbonate (PC), polyimides, copolymers of methyl methacrylate and styrene (MS resins), glass, polyethylene terephthalate (PET), carbon fiber, organic materials, biomaterials, leather, wood, textiles, fabrics, and metals. Also, in the context of the present invention, for example, copolyester resin materials (e.g., Durastar®) may be utilized (e.g., as a molding compound) for the substrate films 102, 103 and / or other elements of the structure. The material(s) used may be electrically conductive, at least locally, or more typically insulating. Furthermore, optical properties, such as opacity / transparency, transmittance, etc., may vary depending on the embodiment.

[0095] In various embodiments, the film(s) 102, 103 may be flexible and therefore may be flexed or otherwise manipulated without breaking during the manufacture of the structure 100. Furthermore, their materials may be selected to assume and retain new shapes in response to, for example, a thermoforming or cold forming procedure.

[0096] The film(s) 102, 103 may be shaped according to the requirements set by each usage scenario. They 102, 103 may exhibit a general shape, for example, rectangular, circular, or square. They 102, 103 may be substantially imperforate. They 102, 103 may also include recesses, cuts, vias, slits, or openings, which may be filled with other material(s) as desired, for various purposes, such as attachment to other elements, conduction of electricity and related, e.g., power or other signals, attachment of electronic devices or other components, providing passage for light or other radiation, fluids, etc.

[0097] One or more layers 112 are applied to any side surface of the film 102, but preferably at least on the first side surface 102A, preferably by an overmolding procedure (from a technical point of view, for example, using injection molding). One or more layers 112 may incorporate, among other options, an elastomeric resin, generally. More specifically, the layer(s) 112 may comprise one or more thermoplastic materials, including at least one material selected from the group consisting of PC, PMMA, ABS (acrylonitrile butadiene styrene), copolyester, copolyester resin, PET (polyethylene terephthalate), nylon (PA, polyamide), PP (polypropylene), TPU (thermoplastic polyurethane), polystyrene (GPPS), TPSiV (thermoplastic silicone vulcanizate), and MS resin. In some embodiments, alternatively or additionally, thermosetting materials may be utilized in conjunction with a suitable molding method, such as reaction molding.

[0098] The film layer(s) 102, 103 as well as the plastic layer(s) 112, or possible further layers 108 (paint, ink, adhesive, film(s), etc.) may be configured to exhibit desired colors or graphic patterns that may be externally perceptible. For example, an IML (In-Mold Labeling) procedure may be used to place embedded graphics into the structure 100.

[0099] 2 illustrates at 200 another embodiment of a multi-layer structure according to the present invention, which may implement, for example, a touch or proximity switch (sensor) function, together with an associated illuminated icon or other graphic, i.e., generally a visual guide.

[0100] The second side of the film 102 is provided with a circuit design comprising several components 104 including at least one light emitting component (light source) such as an LED 204, which may for example be side firing, taking into account their contact / support surface and further elements such as contact pads and / or traces 106. The mounted or fabricated electronic component 104 may additionally comprise a required number of sensing electrodes 205 and sensing electronics such as for example mutual or self-capacitance sensors or sensing switches with control electronics.

[0101] In this example, the first surface of the film 102 may remain essentially free of electronics, but may include a graphics layer 108 illuminated by the component 204 and constructed accordingly, e.g., by coloring, coating, cutting, thinning, and / or shaping the layer 108 (or its material), e.g., with icons 108A or other visual, decorative, and / or informational features. The features 108A may be at least locally light-transmitting, e.g., substantially transparent or translucent, taking into account the material(s) used, and / or may include cutouts, e.g., to allow light to pass through. The features 108A may visually indicate the content of the control input associated with the switch 205, e.g., by distinctive icons and / or text. In some embodiments, the layer 108 may include, e.g., transparent or opaque (masking) material, e.g., in which case the features 108A may be implemented at least partially by translucent / opaque material or transparent / translucent material, respectively. In some embodiments, layer 108 includes material only in features 108A.

[0102] In contrast to the scenario clearly shown in FIG. 2, those skilled in the art will understand that in some alternative or supplemental embodiments of the multilayer structure, at least one light source 204 provided on the second side surface 102B of the film 102 and the desired light directing or light propagating element(s) in their light paths may be configured such that light emitted by the light source 204 is directed at least partially substantially away from the film 102, rather than towards or through the film 102.

[0103] Either of the mechanisms 104, 106 may utilize, for example, optically clear (substantially transparent or at least translucent) conductors to allow light emitted by the component 204 to illuminate through the switch area and printed graphics on the opposite side of the film. The electrode(s) 205 of the switch(es) 104 may be fully transparent or translucent as well. Alternatively or additionally, essentially solid-state switches may be used, such as, for example, self-capacitance switches having notch(es) to allow light to pass through.

[0104] Additional optical devices, such as a light guide 220 or other light propagating or directing member, may be provided on the back side of the substrate film 102, e.g., laminated or heat staked. The light guide 220 may be uniquely formed, e.g., to follow the contours of the in-molded electronic and general structure 200. The light guide 220 may be configured to propagate the incoupled light emitted by the component 204 therein. The light guide 220 may also be configured to extract light through selected surfaces toward, e.g., a graphical icon or other feature 108A that is illuminated in a light path associated with the user and the environment. For example, the light guide 220 may first be formed as a solid sheet and then processed, such as die-cut or punched, to allow holes for placement of light sources, such as LEDs. Thus, in some embodiments, the light guide 220 may at least partially surround or be adjacent to the light source 204.

[0105] Thus, light-emitting components 204 may be positioned in film 102 as desired to, for example, reduce their visibility from the environment of use (e.g., 204 may be positioned behind a masking material provided by layer 108) and / or reduce perceptible hot spots that can easily result from both direct and scattered light reaching a user from within structure 200. Item 204A refers to scattered light emitted by light guide 220. The scattered light propagates within shaped layer 204A and is ultimately output to the user's environment of use. Touch or proximity sensing electronics 205, icon 108A, and lighting arrangements 204, 220, 204A may be configured relative to one another to at least roughly indicate the location of a touch area, or generally a behavior area 230, for recording user input in the environment of use.

[0106] In this embodiment, connections, such as electrical connections, to external elements, such as the electronics of a host device, may optionally be provided exclusively through the back side of structure 200, e.g., the second (back) side of film 102 shown on the right. The connections may include, for example, connection tails (e.g., flex cables or films), rigid connectors, and / or simply contact pads.

[0107] The single film concept represents a low cost option for manufacturing. Additionally, the molded plastic 112 on the first side of the film 102, and thus potentially on the front side of the entire structure or portion, provides for applications where, for example, surface sensitivity to water or moisture may be an issue.

[0108] FIG. 3 illustrates, at 300, a further embodiment of a multilayer structure, which is generally quite similar to the structure of FIG. 1. However, substantially clear (transparent or at least translucent) electrodes 305 for transmitting light emitted by light sources 204 on the second side, as well as circuitry for, for example, the switches described above, such as conductor traces and / or pads 106A, are present on the first side of the substrate film 102. Either of the feature(s) 106A, 305 may alternatively or additionally be provided with opaque conductor material and several cut-out regions or volumes that allow light to pass through. For example, several printed or solid optically substantially opaque conductor / electrode regions may incorporate cut-outs that define a preferred shape, for example, for an illuminated indicator-type icon. Electrical connections can be established to electronics on both sides of the film 102. Electrical connections can be established separately to both sides, for example, via the edges of the structure and associated wiring. With this solution, switch circuits and / or other electronics on a first side of film 102 can be isolated from, for example, LEDs or other light-emitting electronics on a second side by also using film 102 as an electrical insulator.

[0109] FIG. 4 illustrates at 400 yet another embodiment of a multilayer structure. This, too, is only slightly different from the structures described above. One difference is that the electrical connections between the electronics on either side of the film 102 are established by several conductive vias 406, i.e., through-holes (pre-cut or pre-constructed) in the film 102 that are filled with a conductive material, such as, for example, a conductive ink. In some embodiments, a conductive metal, such as, for example, silver, can be printed into existing through-holes, turning them into conductive vias 406. Alternatively, for example, flexible conductors or flex cables can be threaded through the film 102 via applicable slits or, in general, through-holes.

[0110] Thus, in some embodiments that include electrical connections to external elements, it may only be necessary to directly connect the second surface of film 102 to the external element, such as a host device, as opposed to separately connecting them to both sides of film 102, as described in connection with the previous embodiments. The connection between the first surface of film 102 and the external element may be established by intermediate via(s) and connecting element(s) on the second surface.

[0111] Additionally, in some embodiments, several dielectric / insulating or encapsulating layers may be utilized to ensure a stable through-hole design and also allow for improved moldability.

[0112] FIG. 5 illustrates a further embodiment of a multilayer structure at 500. It generally recalls the structures described above, but includes, for example, graphics on an additional second film 103 disposed before the shaped layer 112, i.e., on the opposite side relative to the first film 102. The design thus includes at least two films 102, 103 with a shaped plastic layer 112 disposed therebetween. Generally, as already explained in connection with the description of FIG. 2, the second film 103 facing the first side of the first film 102 opposite the shaped plastic layer 112 contains or is adjacent to a graphics layer 508 incorporating icons or other visual features 508A. This embodiment results in, for example, improved image performance due to the reduced haze and shadowing effects of the features 508A on the remaining structure. The graphics layer 508 and associated features 508A may be disposed on the second side (shown) of the film 103 and / or on the first side that directly faces the environment of use (not shown).

[0113] The two films 102, 103 may comprise or be made of the same or different materials. For example, in some embodiments, the back first film 102 may be made of a plastic material, while the front second film 103 may comprise, for example, metal, textile / fabric, or organic / biomaterial such as wood or leather. In general, the material of the second film 103 may be selected based on aesthetic or tactile properties, such as feel, in addition to the technical properties mentioned above, and in many embodiments, is easily visible and / or touchable to the user.

[0114] FIG. 6 illustrates, at 600, a further embodiment of a slightly modified multilayer structure. The switch electrode 305 is disposed on the first surface of the first substrate film 102. As discussed in connection with the description of FIG. 4, several conductive vias may also be applied here. Item 606 refers to a feature on the second surface of the film 102, extending through the film 102 to the first surface for injection (molding) or, for example, attachment. In some embodiments, item 606 may refer to an extension or protrusion formed into the film 102 from the molding material 112 itself. Thus, item 606 may incorporate a through-hole filled with a solid material.

[0115] FIG. 7 illustrates an embodiment of a multilayer structure including additional “direct light” or “direct illumination” at 700. In particular, light-emitting electronic components, such as top-emitting LEDs 704, are provided on a first surface of film 102, while at least some switching circuitry, such as electrodes 205, is provided on a second surface. Additionally, a graphics layer 508 is provided on second film 103 in the front portion of multilayer structure 700. Item 705 may refer to, for example, an icon or other visual / optical feature, such as an opening or a substantially transparent or translucent portion, within layer 508, which may generally be substantially opaque given the light emitted by components 704. Here, in contrast to the previous example, light 704A is emitted directly from light source 704 to the environment via an intermediate element, such as shaping layer 112. The first and second surfaces of film 102 may be electrically connected separately to external element(s) and / or similarly, both surfaces may be electrically connected together using conductive via(s) through film 102.

[0116] Those skilled in the art will readily appreciate that the above-described merely exemplary embodiments of the present invention may be flexibly and easily combined with selected features to create further embodiments, such as those described elsewhere herein, in connection with the shaping layer(s) provided on the second surface of the film 102.

[0117] FIG. 8 shows a flow diagram 800 disclosing an embodiment of a method for manufacturing a multi-layer structure in accordance with the present invention.

[0118] At the beginning of the manufacturing method for a multilayer structure, an initiation stage 802 can be performed. During initiation 802, necessary tasks such as material, component, equipment and tool selection, acquisition, calibration, and other configuration can be performed. Particular attention must be paid to ensuring that the design, component and material selection work together and withstand the selected manufacturing process. This is naturally preferably confirmed in advance based on the manufacturing process specifications, e.g., component data sheets, or by examining and testing many fabricated prototypes. Thus, the equipment used, such as molding / IML, lamination, bonding, (thermo)forming, electronics assembly, cutting, punching and / or printing equipment, among others, may already be ramped up to operation at this stage or later.

[0119] At 804, at least one substrate film for housing electronic devices is obtained. As discussed above, in some embodiments, only one substrate film is required, while in some other embodiments, multiple substrate films, possibly of different materials, are included in the multilayer structure. Not all films ultimately required will necessarily be loaded with circuitry. Prefabricated elements, such as rolls or sheets of plastic film, may be obtained for use as substrate material. In some embodiments, the substrate film itself may initially be fabricated in-house from the desired starting material(s) by molding or other methods. The substrate film may be substantially uniform and may include essentially only one layer of material. Alternatively, the substrate film may include multiple layers of different materials that are laminated together to form the relevant laminate. Initially, the substrate film may be essentially flat (essentially two-dimensional, meaning a thickness that is fairly small compared to its length and width).

[0120] At 806, certain conductors, such as conductor traces, electrodes, and / or contact pads for electrically coupling electronic components, can be selectively applied to the film(s), preferably by one or more techniques of printed electronics technology, in conjunction with the various possible multilayer structures already identified above. For example, screen printing, inkjet printing, flexographic printing, gravure printing, or offset lithographic printing may be utilized. Further processing of the film(s) can also be performed here, including, for example, printing graphics, visual indicators, etc., onto the film(s). In some embodiments, a graphics or masking layer can be applied by laminating a separate graphics / opaque film or sheet onto the relevant substrate, in addition to or instead of printing onto the substrate.

[0121] 801 generally illustrates how to provide electrical connections through a substrate film. This relates to embodiments where the first and second sides of the film need to be electrically connected to each other to couple associated electronics, and / or where electronics on both sides need to be connected to external elements (e.g., power sources, processors, or communications elements) and where the first side is further electrically coupled to the second side, this can only be done via the second side.

[0122] First, at 818, through-holes, e.g., having polygonal, circular, or elongated (slit-like) cross-sectional shapes, can be provided in the film, e.g., by drilling or cutting. In some other embodiments, the film can be molded or otherwise manufactured to include through-holes directly therein. At 820, the through-holes are filled with a conductive material, such as silver ink, e.g., using printed electronics technology. Alternatively, conductive elements, such as rods, wires, or (flex) cables, can be inserted into the holes. Care is preferably taken to ensure that the fill material or element precisely matches the dimensions of the holes to avoid unnecessary penetration of plastic material through the holes during subsequent molding. At 822, the constructed conductive via(s) can be post-processed to provide several additional layers of material, such as protective barrier layers. Instead of or in addition to conductive vias, optical or other functional connections can be similarly constructed, e.g., by placing optical fibers in the holes that penetrate the substrate film.

[0123] At 808, some electronic components are provided on the film(s) by mounting and / or printing. Preferably, the film, which in use will be at least on the back side, thereby having a molding layer on the front side between the user / environment and the film itself, is provided with, for example, LED or switch circuitry on at least its second, i.e., back, side. Meanwhile, the first side of the film may also include some components and / or other circuitry, or may remain free of them, depending on the particular embodiment in question.

[0124] Prefabricated components such as various SMDs may be attached to the contact areas on the substrate by solder and / or adhesive. Alternatively or additionally, printed electronics techniques may be applied to actually manufacture at least some of the components, such as OLEDs, directly on the film(s).

[0125] Additionally, at this stage or in connection with item 806, various additional features such as light guides or other optical elements may be provided on the film(s), for example by direct fabrication by mounting or printing.

[0126] Additionally, connection element(s), such as electrical connectors or contact pads, may be provided, for example, on the second (back) side of the substrate film, for electrically connecting the multilayer structure to an external device, such as a host device.

[0127] The performance of various method items, such as items 806 and 808, may actually be alternated or overlapped in various embodiments, as will be apparent to one skilled in the art in light of the previously described embodiments illustrated in Figures 1-7. For example, one side of the substrate may first be provided with traces, components, and additional features, as well as a molding layer (see item 812), before switching to processing of the opposite side, which may include similar operations.

[0128] Item 809 refers to the possible attachment of one or more subsystems or "subassemblies" to the substrate film(s). The subassembly may incorporate an initially separate secondary substrate with electronics such as IC(s) and / or various components. At least some of the electronics of the multi-layer structure may be provided on the substrate film(s) via such a subassembly. Optionally, the subassembly may be at least partially overmolded with a protective plastic layer and / or covered with other materials (e.g., epoxy) before attachment to the main substrate. For example, adhesives, pressure, and / or heat may be used to mechanically couple the subassembly to the main (host) substrate. Solder, wiring, and conductive inks are examples of applicable options for providing electrical connections between elements of the subassembly and with the remaining electrical elements of the host substrate.

[0129] At 810, one or more substrates, preferably already containing various components and / or other electronics such as circuitry, are optionally formed to exhibit, at least locally, a desired essentially three-dimensional shape rather than an initial substantially planar shape. Applicable forming methods include, for example, thermoforming and cold forming.

[0130] At 812, at least one layer of material, e.g., a thermoplastic or thermosetting material layer, is molded onto the first side of the first substrate film to at least cover the associated surface and possible features thereon, such as traces, components, and / or graphics layers. For example, in some embodiments where a second film, optionally incorporating graphics, is provided, a plastic layer(s) may be formed therebetween. Alternatively, the second film may be subsequently laminated onto the molded layer of the front portion of the multi-layer structure. Applicable molding techniques include, for example, injection molding (thermoplastic) and reaction injection molding (thermosetting).

[0131] In practice, the substrate film may be used, for example, as an insert in the injection molding process. If two (first and second) films are used, they may both be inserted into each mold half and the plastic layer injected between them.

[0132] If desired, for protection or other reasons, the second side of the first substrate film may also be at least partially overmolded, e.g., to embed thereon electronics within the plastic material. The order of successive molding operations can be selected by those skilled in the art to best suit each embodiment and associated use scenario.

[0133] Optionally, one or more spacing elements may be utilized in connection with the molding procedure to guide, protect, and / or separate selected features (electronics, vias / through-holes, optics, etc.) on the substrate film(s) from the molded plastic and / or mold structures such as walls during molding to keep them clean from the molding material and / or reduce stresses induced therein. Such spacing elements may be subsequently removed or subsequently peeled away.

[0134] To protect fragile features such as electronic components, the overmolding techniques utilized may utilize relatively low molding pressures (e.g., 15 bar or less, more preferably about 10 bar or less). For less delicate parts, higher pressures may be utilized to achieve different material properties.

[0135] In addition to or instead of overmolding, selected electronic components and / or other features may be protected by, for example, potting or resin dispensing.

[0136] Regarding the resulting overall thickness of the resulting laminated structure, it will depend largely on the materials used and the associated minimum material thickness that will provide the necessary strength for manufacturing and subsequent use. These aspects should be considered on a case-by-case basis. For example, the overall thickness of the structure may be on the order of one or several millimeters, although significantly thicker or thinner embodiments are entirely feasible.

[0137] Item 814 denotes possible post-processing tasks. Additional layers may be added to the multilayer structure by lamination or suitable coating (e.g., deposition) procedures. The layers may have protective, display, tactile, and / or aesthetic value (graphics, color, diagrams, text, numerical data, surface texture, etc.). Alternatively, layers may include, for example, textile, leather, or rubber materials instead of or in addition to additional plastics. Additional elements, such as electronics or connection elements (e.g., electrical wiring, cables), may be applied to the outer surface(s) of the structure, such as the outer surface of the substrate film on the back portion of the structure. Forming / cutting may be performed. The connection elements may be connected to desired external elements, such as connectors on an external host device or host structure. The multilayer structure may be applied to the target device or structure (e.g., housing), if any.

[0138] At 816, execution of the method ends.

[0139] The scope of the present invention is determined by the appended claims and their equivalents. Those skilled in the art will appreciate that the disclosed embodiments are merely illustrative and that other devices applying many of the principles described above can be readily prepared to best suit each possible usage scenario. For example, instead of or in addition to molding plastic directly onto a substrate, a plastic layer can be pre-prepared and then attached to the substrate by a suitable lamination technique, for example, applying adhesive, mechanical attachment means (screws, bolts, nails, etc.), pressure, and / or heat. Finally, in some scenarios, instead of molding, a plastic layer or other layer of similar functionality can be fabricated on the substrate using a suitable deposition method or further alternative method. Furthermore, instead of printed traces, traces can be fabricated / placed by other methods. For example, a conductor film fabricated using etching, among other options, can be applied.

[0140] The following are appendices to the present disclosure. (Additional note 1) a first substrate film (102) having a first side surface (102A) and an opposing second side surface (102B), the first substrate film comprising a substantially electrically insulating material; a plastic layer (112) molded on the first side of the first substrate film so as to at least partially cover the first side; a circuit (104, 106, 204, 205) provided on the second surface of the first substrate film, the circuit being functionally connected to the first surface of the first substrate film; Integral multi-layer structures (100, 200, 300, 400, 500, 600, 700) including: (Additional note 2) a second substrate film (103) on the side of said plastic layer opposite said first substrate film, optionally containing graphics and / or circuitry on said second substrate film; the second substrate film optionally comprises a polymer, an organic material, a biomaterial, leather, wood, a textile, a fabric, and / or a metal; The structure according to claim 1. (Additional note 3) The second substrate film is a first surface and an opposing second surface, the second surface facing the molded plastic layer and having features and optionally circuitry disposed on at least the second surface; The structure according to appended item 2. (Additional note 4) including an embedded color or graphics layer (108, 508) preferably showing selected colors, figures, icons, graphic patterns, symbols, text, numbers, alphanumeric characters, and / or other visual indicators (108A, 508A); The structure according to any one of claims 1 to 3. (Additional note 5) a number of conductors, optionally defining traces, electrodes, and / or contact pads, printed on said second surface of said first substrate film and optionally connected to at least one component provided on said second surface, at least some of said conductors being optionally substantially optically transparent to a selected wavelength, such as visible light; The structure according to any one of claims 1 to 4. (Additional note 6) the circuit includes a light source, optionally an LED; Preferably, the present invention further includes a light guide provided on the second side of the first substrate film, the light guide directing light emitted by the light source and internally coupled into the light guide to propagate inside the light guide and exit through a selected surface toward the first substrate film and the plastic layer, the first substrate film and the plastic layer comprise a light-transmitting material, the light-transmitting material being preferably a substantially transparent or at least translucent material having regard to the wavelengths emitted by the light source, optionally including visible light; The structure according to any one of claims 1 to 5. (Additional note 7) a further circuit (104, 704) disposed on the first surface of the substrate film and at least partially embedded in the plastic layer; the further circuitry optionally comprises electronic, electro-optical or electro-mechanical components, and optionally comprises a light source such as an LED; The structure according to any one of claims 1 to 6. (Additional note 8) a number of conductors, optionally incorporating traces, electrodes, and / or contact pads, printed on said first side of said first substrate film and optionally connected to at least one component provided on said first side, at least a portion of said conductors being optionally substantially optically transparent to a selected wavelength, such as visible light; The structure according to any one of claims 1 to 7. (Additional note 9) at least the first substrate film exhibits, at least locally, a formed, substantially three-dimensional, non-planar shape; The structure according to any one of claims 1 to 8. (Additional note 10) including conductive vias extending through said first substrate film, preferably connecting circuitry on either side of said first substrate film; The structure according to any one of claims 1 to 9. (Additional note 11) Preferably, a layer of thermoplastic or thermosetting plastic material is optionally formed on the second side of the first substrate film, preferably including a protective layer covering at least a part of the at least one component; the material of the protective layer is optionally different from the material of the plastic layer; The structure according to any one of claims 1 to 10. (Additional note 12) The circuit comprising at least one feature selected from the group consisting of an electronic component, an electro-optical component, an electromechanical component, a radiation emitting component, a light emitting component, an LED (light emitting diode), an OLED (organic LED), a radiation detecting component, a light detecting component, a photodiode, a phototransistor, a photovoltaic device such as a cell, a sensor, an air sensor, a gas sensor, a temperature sensor, a humidity sensor, a micromechanical component, a switch, a contact switch, a proximity switch, a contact sensor, a proximity sensor, a capacitive switch, a capacitive sensor, a projected capacitive switch or sensor, a single electrode capacitive switch or sensor, a multi-pole capacitive switch or sensor, a self-capacitance sensor, a mutual capacitance sensor, an inductive sensor, a sensor electrode, a UI (user interface) element, a user input element, a vibration element, a communication element, a data processing element, and a data storage element; The structure according to any one of claims 1 to 11. (Additional note 13) the molded plastic layer The material comprises at least one material selected from the group consisting of elastomer resins, thermosetting materials, thermoplastic materials, PC, PMMA, ABS, PET, copolyesters, copolyester resins, nylon (PA, polyamide), PP (polypropylene), TPU (thermoplastic polyurethane), polystyrene (GPPS), TPSiV (thermoplastic silicone vulcanizate), and MS resin; The structure according to any one of claims 1 to 12. (Additional note 14) The first substrate film is The material comprises at least one material selected from the group consisting of polymers, thermoplastic materials, electrically insulating materials, PMMA (polymethyl methacrylate), polycarbonate (PC), copolyesters, copolyester resins, polyimides, copolymers of methyl methacrylate and styrene (MS resins), glass, polyethylene terephthalate (PET), carbon fibers, organic materials, biomaterials, leather, wood, textiles, fabrics, and metals. The structure according to any one of claims 1 to 13. (Additional note 15) a cooling element, such as a heat sink or a thermoelectric element, on the second surface of the first substrate film, configured to optionally cool the circuit and thereby control temperature; The structure according to any one of claims 1 to 14. (Additional note 16) a spacer on the second surface (102B) of the first substrate film (102) configured to optionally define a light guide (220) and protect at least a portion of the circuit, including optionally a light source (204), during and / or after molding of the plastic layer; the spacer preferably includes a hole for receiving said at least part of said circuit, the space remaining in said hole being optionally filled with further protective material; The structure according to any one of claims 1 to 15. (Additional note 17) A host device (110) including the structure described in any one of supplementary items 1 to 16. (Additional note 18) 18. The host device of claim 17, comprising at least one element selected from the group consisting of an electronic terminal device, a personal electronic device, a portable terminal device, a personal digital assistant device or controller, a vehicle, a car, a truck, an airplane, a helicopter, an on-board structure, an on-board panel, an on-board electronic device, a vehicle dashboard, a vehicle exterior element, a vehicle lighting device, a measuring device, a computing device, intelligent clothing, a part of a wearable electronic device, a multimedia device or player, an industrial machine, a controller device, and a personal communication device. (Additional note 19) obtaining (804) a first substrate film for housing an electronic device, the first substrate film having a first side surface and an opposing second side surface, the first substrate film comprising an electrically substantially insulating material, the first substrate film being preferably moldable and / or thermoplastic; providing (808) circuitry on at least the second surface of the first substrate film, optionally by packaging and / or by printed electronics techniques, the circuitry being operatively connected to the first surface of the first substrate film; and, molding (812) a plastic material onto the first surface of the first substrate film, optionally by injection molding or reaction molding, so as to at least partially cover the first surface; A method (800) for producing a multi-layer structure, comprising: (Additional note 20) 20. The method of claim 19, further comprising molding a second plastic layer onto the second surface of the first substrate film, preferably by low-pressure injection molding. (Additional note 21) After providing at least a portion of the circuitry, such as one or more components and / or traces, on the film, forming the first substrate at least locally or more globally to exhibit a selected essentially three-dimensional shape; The method according to claim 19 or 20. (Additional note 22) embedding, optionally by lamination and / or printing, into the multi-layer structure at least one color or graphics layer (108, 508), preferably defining selected colors, figures, icons, graphic patterns, symbols, text, numbers, alphanumeric characters, and / or other visible indicator features (108A, 508A); A method according to any one of appendix 19 to appendix 21. (Additional note 23) providing a second film on the side of the plastic layer opposite the first substrate film, optionally housing graphics and / or electronics on the second film; A method according to any one of appendix 19 to appendix 22. (Additional note 24) providing conductive vias in the first substrate film to electrically couple circuits on both sides of the first substrate film; A method according to any one of appendix 19 to appendix 23. (Additional note 25) 1. A substrate film for use in an electronic device, comprising: comprising or consisting essentially of a moldable, optionally thermoformable material such as a thermoplastic material; at least one via substantially filled with a formable and conductive material, optionally a thermoformable conductive ink, for electrically coupling opposing first and second side surfaces of the substrate film to one another; Substrate film. (Additional note 26) Obtaining a substrate film of a formable material to host an electronic device; constructing through holes in the substrate film; providing said through holes with a conductive formable material, optionally with a formable conductive ink, preferably by printing; Including, The method, wherein the material electrically connects and extends substantially between a first side surface of the substrate film and an opposing second side surface of the substrate film.

Claims

1. a first substrate film (102) having a first side surface (102A) and an opposing second side surface (102B), the first substrate film comprising an electrically insulating material and being moldable and / or thermoplastic; a plastic layer (112) that is injection molded or reaction molded on the first side of the first substrate film so as to at least partially cover the first side; a circuit (104, 106, 204, 205) provided on the second surface of the first substrate film, the circuit being operatively connected to the first surface of the first substrate film and including at least one electronic, electromechanical and / or electro-optical component, including at least one light source or a light-sensitive or light-receiving component, some conductors being additionally printed on the first surface of the first substrate film and at least partially covered by the plastic layer (112), at least some of the conductors being optically transparent or at least translucent to allow light to pass through; An integral multi-layer structure (100, 200, 300, 400, 500, 600, 700) comprising:

2. a second substrate film (103) on the side of the plastic layer opposite the first substrate film, containing graphics and / or circuitry on the second substrate film; the second substrate film comprises a polymer, an organic material, a biomaterial, leather, wood, a textile, a fabric, and / or a metal; The structure of claim 1 .

3. The second substrate film is a first surface and an opposing second surface, the second surface facing the molded plastic layer and having several features and including circuitry disposed on at least the second surface; The structure of claim 2 .

4. including an embedded color or graphics layer (108, 508) that displays selected colors, figures, icons, graphic patterns, symbols, text, numbers, alphanumeric characters, and / or other visual indicators (108A, 508A); A structure according to any one of claims 1 to 3.

5. a number of conductors defining traces, electrodes, and / or contact pads are printed on the second surface of the first substrate film and connected to at least one component disposed on the second surface, at least some of the conductors being substantially optically transparent to selected wavelengths including visible light; A structure according to any one of claims 1 to 4.

6. the circuit includes a light source, or an LED; further comprising a light guide disposed on the second surface of the first substrate film, the light guide directing light emitted by the light source and internally coupled into the light guide to propagate within the light guide and exit through a selected surface toward the first substrate film and the plastic layer; the first substrate film and the plastic layer comprise a light-transmitting material, the light-transmitting material being substantially transparent or at least translucent considering wavelengths emitted by the light source, including visible light; A structure according to any one of claims 1 to 5.

7. a further circuit (104, 704) disposed on the first side of the first substrate film and at least partially embedded in the plastic layer; the further circuitry comprises electronic, electro-optical or electro-mechanical components; A structure according to any one of claims 1 to 6.

8. the number of conductors printed on the first surface of the first substrate film incorporate traces, electrodes, and / or contact pads and are connected to at least one component provided on the first surface; A structure according to any one of claims 1 to 7.

9. at least the first substrate film exhibits, at least locally, a formed, substantially three-dimensional, non-planar shape; A structure according to any one of claims 1 to 8.

10. a conductive via extending through the first substrate film and connecting circuits on opposite sides of the first substrate film; A structure according to any one of claims 1 to 9.

11. a layer of thermoplastic or thermosetting plastic material is formed on the second surface of the first substrate film and includes a protective layer covering at least a portion of the at least one component; the material of the protective layer is different from the material of the plastic layer; The structure of claim 5.

12. The circuit comprising at least one feature selected from the group consisting of an electronic component, an electro-optical component, an electromechanical component, a radiation emitting component, a light emitting component, an LED (light emitting diode), an OLED (organic LED), a radiation detecting component, a light detecting component, a photodiode, a phototransistor, a photovoltaic device including a cell, a sensor, an air sensor, a gas sensor, a temperature sensor, a humidity sensor, a micromechanical component, a switch, a contact switch, a proximity switch, a contact sensor, a proximity sensor, a capacitive switch, a capacitive sensor, a projected capacitive switch or sensor, a single electrode capacitive switch or sensor, a multi-pole capacitive switch or sensor, a self-capacitance sensor, a mutual capacitance sensor, an inductive sensor, a sensor electrode, a UI (user interface) element, a user input element, a vibration element, a communication element, a data processing element, and a data storage element; A structure according to any one of claims 1 to 11.

13. The molded plastic layer is The material comprises at least one material selected from the group consisting of elastomer resins, thermosetting materials, thermoplastic materials, PC, PMMA, ABS, PET, copolyesters, copolyester resins, nylon (PA, polyamide), PP (polypropylene), TPU (thermoplastic polyurethane), polystyrene (GPPS), TPSiV (thermoplastic silicone vulcanizate), and MS resins; A structure according to any one of claims 1 to 12.

14. The first substrate film is The material comprises at least one material selected from the group consisting of polymers, thermoplastic materials, electrically insulating materials, PMMA (polymethyl methacrylate), polycarbonate (PC), copolyesters, copolyester resins, polyimides, copolymers of methyl methacrylate and styrene (MS resins), glass, polyethylene terephthalate (PET), carbon fibers, organic materials, biomaterials, leather, wood, textiles, fabrics, and metals; A structure according to any one of claims 1 to 13.

15. a cooling element including a heat sink or a thermoelectric element on the second surface of the first substrate film configured to cool the circuit and thereby control temperature; A structure according to any one of claims 1 to 14.

16. a spacer on the second surface (102B) of the first substrate film (102) that defines a light guide (220) and is configured to protect at least a portion of the circuit, including the light source (204), during and / or after molding of the plastic layer; the spacer includes a hole for receiving the at least a portion of the circuit, and the space remaining in the hole is filled with a further protective material. A structure according to any one of claims 1 to 15.

17. A host device (110) comprising a structure according to any one of claims 1 to 16.

18. 20. The host device of claim 17, comprising at least one element selected from the group consisting of an electronic terminal device, a personal electronic device, a portable terminal device, a personal digital assistant device or controller, a vehicle, a car, a truck, an airplane, a helicopter, an on-board structure, an on-board panel, an on-board electronic device, a vehicle dashboard, a vehicle exterior element, a vehicle lighting device, a measuring device, a computing device, intelligent clothing, a part of a wearable electronic device, a multimedia device or player, an industrial machine, a controller device, and a personal communication device.

19. obtaining (804) a first substrate film for housing an electronic device, the first substrate film having a first side and an opposing second side, the first substrate film comprising an electrically insulating material, and the first substrate film being moldable and / or thermoplastic; providing (808) a circuit on at least the second surface of the first substrate film by packaging and / or by printed electronics techniques, the circuit being operatively connected to the first surface of the first substrate film, the circuit (104, 106, 204, 205) including at least one electronic, electromechanical, and / or electro-optical component, including at least one light source or light sensitive or light receiving component; additionally printing several conductors onto the first surface of the first substrate film, at least some of the conductors being optically transparent or at least translucent to allow light to pass through; and A method (800) for manufacturing a multilayer structure, comprising: injection molding or reaction molding (812) a plastic layer onto the first side surface of the first substrate film so as to at least partially cover the first side surface of the first substrate film and some of the conductors printed on the first side surface.

20. 20. The method of claim 19, comprising molding a second plastic layer onto the second surface of the first substrate film by low pressure injection molding.

21. After providing at least a portion of the circuit, including one or more components and / or traces, on the film, forming a first substrate at least locally or more globally to exhibit a selected essentially three-dimensional shape; 21. The method of claim 19 or claim 20.

22. embedding, by lamination and / or printing, at least one color or graphics layer (108, 508) into the multi-layer structure that defines selected colors, figures, icons, graphic patterns, symbols, text, numbers, alphanumeric characters, and / or other visible indicator features (108A, 508A); 22. The method according to any one of claims 19 to 21.

23. providing a second film on the plastic layer opposite the first substrate film, the second film housing graphics and / or electronics.

23. The method according to any one of claims 19 to 22.

24. providing conductive vias in the first substrate film to electrically couple circuits on both sides of the first substrate film; 24. The method according to any one of claims 19 to 23.

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