Systems and methods for inspection of encapsulation, and components in sensor-equipped wound dressings

Abstract

To provide methods of inspection and manufacture of flexible printed circuit boards and flexible sensor sheets to enable improved sensor monitoring, and apparatuses such as wound dressing components utilizing the same.SOLUTION: Disclosed herein are embodiments of methods of inspection and manufacture of flexible printed circuit boards and flexible sensor sheets, and apparatuses such as wound dressing components utilizing the same. The methods can comprise applying a coating material to a flexible printed circuit board, where the coating material comprises a material that will fluoresce when exposed to UV or visible light, and where the flexible printed circuit board comprises one or more electronic components. The coated flexible printed circuit board can be positioned under UV or visible light to cause the coating material to fluoresce.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 62 / 556,479, filed September 10, 2017, which is incorporated by reference in its entirety and made a part of this disclosure. [Background technology]

[0002] Embodiments of the present disclosure relate to devices, systems, and methods for treatment of tissue via sensor-enabled monitoring in communication with various treatment modalities.

[0003] 2. Description of Related Art Nearly every area of ​​medicine could benefit from improved information about the condition of the tissue, organ, or system being treated, especially if such information is collected in real time during treatment. Many types of treatments are still routinely performed without the use of sensor data collection, but instead, such treatments rely on visual inspection by a caregiver or other limited means rather than quantitative sensor data. For example, in the case of wound treatment via dressings and / or negative pressure wound therapy, data collection is generally limited to visual inspection by a caregiver, and often the underlying wound tissue may be obscured by bandages or other visual obstructions. Even undamaged, intact skin may have underlying damage that is not visible to the naked eye, such as vascular damage or deep tissue damage that may lead to ulcers. Similar to wound treatment, during orthopedic procedures that require immobilization of a limb with a cast or other covering, only limited information is collected about the underlying tissue. In the case of internal tissue repairs, such as bone plates, continuous direct sensor-driven data collection is not performed. Additionally, fasteners and / or sleeves used to preserve musculoskeletal function do not monitor the function of the underlying muscles or movement of the limb. Outside of direct treatment, common hospital room items such as beds and blankets can be improved by adding the ability to monitor patient parameters.

[0004] Thus, there is a need for improved sensor monitoring, particularly through the use of sensor-enabled substrates that can be integrated into existing therapeutic methods.

[0005] Various types of wound dressings are known to aid in the healing process of humans or animals. The various types of wound dressings include various types of materials and layers, such as gauze, pads, foam pads, or multi-layer wound dressings. Local negative pressure therapy, sometimes referred to as vacuum-assisted closure therapy, negative pressure wound therapy, or reduced pressure wound therapy, is widely recognized as a beneficial mechanism for improving the healing rate of wounds. Such therapy can be applied to a wide range of wounds, such as incisional wounds, open wounds, and abdominal wounds.

[0006] However, prior art dressings for use in negative pressure wound therapy or other wound therapies provide little visibility or information about the condition of the wound site underneath the dressing. This may require premature replacement of the dressing before the wound has healed to a desired level, or, in the case of absorbent dressings, before the full absorbent capacity of the dressing is reached, to allow a clinician to visually inspect the wound's healing and condition. Some current dressings have limited or insufficient methods or features for providing information about the wound's condition.

[0007] In some wound dressings, there may be a need to utilize electronic components within the wound and / or wound dressing. The electronic components and other devices of the wound dressing may require the use of coatings and / or adhesives and other seals to protect the electronic components and / or the patient. If the coating or adhesive is transparent, it may be difficult to determine if the electronic components are completely covered or if the coating and / or adhesive is properly applied. This can make it particularly difficult for medical devices to maintain biocompatibility. Summary of the Invention

[0008] According to some embodiments, a method of inspection of a flexible printed circuit board is provided that can include applying a coating material to a flexible printed circuit board, the coating material including a material that fluoresces when exposed to UV or visible light, the flexible printed circuit board including one or more electronic components, and positioning the coated flexible printed circuit board under the UV or visible light to cause the coating material to fluoresce.

[0009] The method of inspecting a flexible printed circuit board as described in any of the preceding paragraphs may further include one or more of the following features: The coating material may include an adhesive material. The coating material may include an acrylated polyurethane. The method may further include displaying an image of the flexible printed circuit board under UV or visible light on a display. The image on the display may indicate the location of the coating material. The image on the display may indicate the location of one or more electronic components and / or one or more electronic connections or tracks under the coating material. The UV or visible light may be transmitted from a light source on the same side of the flexible printed circuit board as the light sensor. The UV or visible light may be transmitted from a light source on the opposite side of the flexible printed circuit board from the light sensor. The method may further include measuring a fluorescence intensity of the coating material while exposed to the UV or visible light. The one or more electronic components may be visible through the coating material under the UV or visible light. The method may further include positioning the flexible printed circuit board under UV light and under visible light. The method may further include displaying images of the flexible circuit board under different wavelengths of visible light and / or UV light. The method may further include testing the flexible printed circuit board for corona discharge.The method may further include taking an image of the location of the corona discharge.

[0010] According to some embodiments, there is provided a method of manufacturing a flexible sensor sheet for use on a wound, the method comprising providing a flexible substrate, positioning an electronic component on the flexible substrate including one or more sensors for detecting wound characteristics, applying a coating material over the flexible substrate and / or the electronic component, and positioning the flexible substrate under UV or visible light to cause the coating material to fluoresce.

[0011] The manufacturing method described in any of the preceding paragraphs may further include one or more of the following features: The coating material may include an adhesive material. The coating material may include an acrylated polyurethane. The method may further include displaying an image of the flexible substrate under UV or visible light on a display. The image on the display may indicate the location of the coating material. The image on the display indicates the location of the electronic components under the coating material. The UV or visible light is transmitted from a light source on the same side of the flexible substrate as the light sensor. The UV or visible light is transmitted from a light source on the flexible printed circuit board on an opposite side of the light sensor. The method may further include measuring a fluorescence intensity of the coating material while exposed to the UV or visible light. The electronic components may be visible through the coating material under the UV or visible light. The method may further include positioning the flexible substrate under UV light and under visible light. The method may further include displaying an image of the flexible substrate under different visible wavelengths and / or UV light. The method may further include testing the flexible printed circuit board for corona discharge. The method may further include taking an image of the location of the corona discharge.

[0012] According to some embodiments, a flexible sensor sheet for use on a wound is provided that can include a flexible substrate, an electronic component including one or more sensors positioned on the flexible substrate for detecting wound characteristics, and a material that fluoresces when exposed to UV or visible light coating the flexible substrate and / or the electronic component.

[0013] In some embodiments, what is described in any of the preceding paragraphs can include one or more of the following features: The material that fluoresces when exposed to UV or visible light can include an adhesive material. The material that fluoresces when exposed to UV or visible light can include an acrylated polyurethane. A first portion of the flexible substrate can be coated with a first material that fluoresces when exposed to UV or visible light, and a second portion of the flexible substrate can be coated with a second material that fluoresces when exposed to UV or visible light, and the first material can be different from the second material.

[0014] According to some embodiments, a method of inspecting a flexible printed circuit board or a flexible sensor sheet is provided, the method may include testing the flexible printed circuit board for corona discharge.

[0015] According to some embodiments, a method of inspecting a flexible printed circuit board is provided that can include applying a coating material to a flexible printed circuit board, where the coating material includes a material configured to fluoresce when exposed to UV or visible light, where the flexible printed circuit board includes one or more electronic components; positioning the coated flexible printed circuit board under UV or visible light to cause the coating material to fluoresce; measuring the fluorescent emission of the coating material to detect voids or uneven application of the coating material; and measuring the light transmittance of the coating material to detect gas bubbles in the coating material.

[0016] The method described in any of the preceding paragraphs may further include one or more of the following features: The wound-facing surface of the flexible printed circuit board may be exposed to UV or visible light. The opposite side of the wound-facing surface of the flexible printed circuit board may be exposed to UV or visible light. The coating material may include an adhesive material. The coating material may include an acrylated polyurethane. The method may further include displaying an image of the flexible printed circuit board under UV or visible light on a display. The image on the display may indicate the location of the coating material. The image on the display may indicate the location of one or more electronic components beneath the coating material. The UV or visible light may be transmitted from a light source on the same side of the flexible printed circuit board as the light sensor. The UV or visible light may be transmitted from a light source on the flexible printed circuit board opposite the light sensor. The method may further include measuring the fluorescence intensity of the coating material while exposed to UV or visible light. The one or more electronic components may be visible through the coating material under UV or visible light. The method may further include positioning the flexible printed circuit board under UV light and visible light. The method may further include displaying images of the flexible printed circuit board under different visible wavelengths and / or UV light. The method may further include testing the flexible printed circuit board for corona discharge. The method may further include taking an image of the location of the corona discharge.

[0017] According to some embodiments, a method of inspecting a compliant and flexible printed circuit board is provided, the method including applying a coating material to the compliant and flexible printed circuit board, the coating material including a material that fluoresces when exposed to UV or visible light, the compliant and flexible printed circuit board including one or more electronic components, and positioning the coated compliant and flexible printed circuit board under the UV or visible light to cause the coating material to fluoresce.

[0018] Other embodiments of the wound dressings, devices, kits, and associated methods are described below. [Brief description of the drawings]

[0019] Embodiments of the present disclosure will now be described, by way of example only, with reference to the accompanying drawings, in which: [Figure 1] FIG. 1 illustrates a negative pressure wound treatment system, according to some embodiments. [Diagram 2] 1 illustrates a wound dressing and a fluid connector according to some embodiments. [Figure 3A] FIG. 1 illustrates a sensor array that can be incorporated into a wound dressing according to some embodiments. [Figure 3B] 1 illustrates a sensor portion of a sensor array according to some embodiments. [Figure 3C-1] FIG. 2 illustrates an example control module, according to some embodiments. [Figure 3C-2] FIG. 2 illustrates an example control module, according to some embodiments. [Figure 3C-3] FIG. 2 illustrates an example control module, according to some embodiments. [Figure 4A] 1A-1C illustrate components for use in a wound dressing having multiple electronic components, according to some embodiments. [Figure 4B] 1A-1C illustrate components for use in a wound dressing having multiple electronic components, according to some embodiments. [Figure 5A] 1 illustrates an embodiment of a flexible printed circuit board having a UV-initiated material coating or adhesive. [Figure 5B] 1 illustrates an embodiment of a flexible printed circuit board having a UV-initiated material coating or adhesive. [Figure 6A] FIG. 1 illustrates a flexible sensor array printed wiring with a coating or adhesive of a UV-initiated material under UV light. [Figure 6B] FIG. 1 illustrates a flexible sensor array printed wiring with a coating or adhesive of a UV-initiated material under UV light. [Figure 6C] FIG. 1 illustrates a flexible sensor array printed wiring with a coating or adhesive of a UV-initiated material under UV light. [Figure 6D] FIG. 1 illustrates a flexible sensor array printed wiring with a coating or adhesive of a UV-initiated material under UV light. [Figure 7A] FIG. 1 illustrates a flexible sheet having a coating or adhesive of a UV-initiated material under UV light. [Figure 7B] FIG. 1 illustrates a flexible sheet having a coating or adhesive of a UV-initiated material under UV light. [Figure 8A] 1 illustrates an embodiment of a flexible sheet having electronic components and electronic connections thereon. [Figure 8B] 1 illustrates an embodiment of a flexible sheet having electronic components and electronic connections thereon. [Figure 8C] 1 illustrates an embodiment of a flexible sheet having electronic components and electronic connections thereon. [Figure 8D] 1 illustrates an embodiment of a flexible sheet having electronic components and electronic connections thereon. [Figure 9A] FIG. 1 illustrates an embodiment of a sheet coated with an adhesive or coating that fluoresces under UV light. [Figure 9B] FIG. 1 illustrates an embodiment of a sheet coated with an adhesive or coating that fluoresces under UV light. [Figure 9C] FIG. 1 illustrates an embodiment of a sheet coated with an adhesive or coating that fluoresces under UV light. [Figure 10A] FIG. 1 illustrates an experimental set-up of a sheet or other material coated with one or more coatings or adhesives. [Figure 10B]FIG. 1 illustrates an experimental set-up of a sheet or other material coated with one or more coatings or adhesives. [Figure 10C] FIG. 1 illustrates an experimental set-up of a sheet or other material coated with one or more coatings or adhesives. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] The embodiments disclosed herein relate to devices and methods for monitoring and treating biological tissue with a sensor-enabled substrate. The embodiments disclosed herein are not limited to treating or monitoring a particular type of tissue or injury, instead the sensor-enabled technology disclosed herein is broadly applicable to any type of therapy that may benefit from a sensor-enabled substrate. Some implementations utilize sensors and data collection requested by healthcare providers to make both diagnostic and patient management decisions.

[0021] Some embodiments disclosed herein relate to the use of sensors attached or incorporated into substrates configured for use in the treatment of both intact and damaged human or animal tissue. Such sensors can collect information about the surrounding tissue and transmit such information to a computing device or a caregiver for further treatment. In certain embodiments, such sensors can be attached to the skin anywhere on the body, including areas for monitoring arthritis, temperature, or other areas that may be problematic and require monitoring. The sensors disclosed herein can also incorporate markers, such as radiopaque markers, to indicate the presence of the device, for example, before performing an MRI or other technique.

[0022] The sensor embodiments disclosed herein can be used in combination with clothing. Non-limiting examples of clothing for use with the sensor embodiments disclosed herein include shirts, pants, pantaloons, dresses, underwear, jackets, gloves, shoes, hats, and other suitable garments. In certain embodiments, the sensor embodiments disclosed herein can be fused to or laminated into a particular garment. The sensor embodiments can be printed directly onto the garment and / or embedded within the textile. Breathable and printable materials such as microporous membranes can also be suitable.

[0023] Sensor embodiments disclosed herein can be incorporated into cushioning or bed padding, such as in hospital beds, to monitor patient characteristics, such as any of the characteristics disclosed herein. In certain embodiments, disposable films containing such sensors can be placed over the hospital bedding and removed / replaced as needed.

[0024] In some implementations, the sensor embodiments disclosed herein can incorporate energy harvesting such that the sensor embodiments are autonomous. For example, energy can be harvested from a thermal energy source, a kinetic energy source, a chemical gradient, or any suitable energy source.

[0025] The sensor embodiments disclosed herein may be utilized in rehabilitation devices and treatments, including sports medicine. For example, the sensor embodiments disclosed herein may be used in braces, sleeves, wraps, supports, and other suitable items. Similarly, the sensor embodiments disclosed herein may be incorporated into sports equipment, such as helmets, sleeves, and / or pads. For example, such sensor embodiments may be incorporated into protective helmets to monitor characteristics such as acceleration that may be useful in diagnosis.

[0026] The sensor embodiments disclosed herein can be used in concert with a surgical device, for example, the NAVIO Surgical System by Smith & Nephew Inc. In implementations, the sensor embodiments disclosed herein can communicate with the surgical device to guide the placement of the surgical device. In some implementations, the sensor embodiments disclosed herein can monitor blood flow to a potential surgical site or ensure that there is no blood flow to the surgical site. Additional surgical data can be collected to help prevent scarring and to monitor areas remote from the affected area.

[0027] To further aid in surgical techniques, the sensors disclosed herein may be incorporated into surgical drapes to provide information about tissue beneath the drape that is not directly visible to the naked eye. For example, a sensor-embedded flexible drape may have sensors strategically positioned to provide improved area-focused data collection. In certain implementations, the sensor embodiments disclosed herein may be incorporated into the boundary or interior of the drape to create a fence to restrict / control the surgical system.

[0028] The sensor embodiments disclosed herein can also be utilized for pre-surgical evaluation. For example, such sensor embodiments can be used to gather information about potential surgical sites by monitoring the skin and underlying tissue for potential incision sites. For example, perfusion levels or other suitable characteristics can be monitored at the surface of the skin and deep within the tissue to assess whether an individual patient may be at risk for surgical complications. Sensor embodiments such as those disclosed herein can be used to assess the presence of bacterial infection and provide an indication for the use of antimicrobial agents. Additionally, sensor embodiments disclosed herein can gather additional information in deep tissues, such as identifying pressure ulcer damage and / or adipose tissue levels.

[0029] The sensor embodiments disclosed herein can be utilized for cardiovascular monitoring. For example, such sensor embodiments can be incorporated into a flexible cardiovascular monitor that can be placed on the skin to monitor characteristics of the cardiovascular system and transmit such information to another device and / or a caregiver. For example, such a device can monitor pulse rate, blood oxygenation, and / or cardiac electrical activity. Similarly, the sensor embodiments disclosed herein can be utilized for neurophysiological applications, such as monitoring neuronal electrical activity.

[0030] The sensor embodiments disclosed herein may be incorporated into implantable devices, such as implantable orthopedic implants, including flexible implants. Such sensor embodiments may be configured to collect information about the implant site and transmit this information to an external source. In some embodiments, an internal source may also provide power for such implants.

[0031] The sensor embodiments disclosed herein may also be utilized to monitor biochemical activity on or below the surface of the skin, such as lactose accumulation in muscles or sweat production on the surface of the skin. In some embodiments, other characteristics may be monitored, such as glucose concentration, urine concentration, tissue pressure, skin temperature, skin surface conductivity, skin surface resistivity, skin hydration, skin maceration, and / or skin ripping.

[0032] The sensor embodiments disclosed herein may be incorporated into ear, nose and throat (ENT) applications, for example, such sensor embodiments may be utilized to monitor recovery from ENT-related procedures, such as wound monitoring in the nasal passages.

[0033] As described in more detail below, sensor embodiments disclosed herein can incorporate sensor printing techniques with encapsulation, such as encapsulation with a polymer film. Such films can be constructed using any of the polymers described herein, such as polyurethane. Encapsulation of sensor embodiments can provide waterproofing and protection of the electronics from local tissue, local liquids, and other potential sources of damage.

[0034] In certain embodiments, the sensors disclosed herein can be incorporated into an organ protection layer as disclosed below. Such a sensor-incorporated organ protection layer can protect the target organ and verify that the organ protection layer is in place to provide protection. Additionally, the sensor-incorporated organ protection layer can be utilized to monitor the underlying organ by monitoring blood flow, oxygenation, and other suitable markers of organ health. In some embodiments, the transplanted organ can be monitored by monitoring the fat and muscle content of the organ. The sensor-enabled organ protection layer may be used to monitor the organ during and after transplantation, such as during organ rehabilitation.

[0035] The sensor embodiments disclosed herein can be incorporated into treatments for wounds (disclosed in more detail below) or a variety of other applications. Non-limiting examples of additional applications of the sensor embodiments disclosed herein include monitoring and treatment of intact skin, cardiovascular applications to monitor blood flow, orthopedic applications such as monitoring limb movement and bone repair, neurophysiological applications such as monitoring electrical impulses, and any other tissue, organ, system, or condition that can benefit from improved sensor-enabled monitoring.

[0036] wound therapy Some embodiments disclosed herein relate to wound therapy for the human or animal body. Thus, any reference to a wound herein may refer to a wound on a human or animal body, and any reference to a body herein may refer to a human or animal body. Disclosed technology embodiments may relate to preventing or minimizing damage to physiological or biological tissues, or treating damaged tissue (such as wounds described herein) with or without reduced pressure, including, for example, negative pressure sources and wound dressing components and devices. Devices and components, including wound overlays and packing materials, or inner layers, if present, are sometimes collectively referred to herein as dressings. In some embodiments, wound dressings may be provided to be utilized without reduced pressure.

[0037] Some embodiments disclosed herein relate to wound therapy for human or animal body. Thus, any reference to wound herein can refer to a wound on a human or animal body, and any reference to body herein can refer to a human or animal body. Disclosed technology embodiments can be related to preventing or minimizing damage to physiological or biological tissue, or treatment of damaged tissue (such as wounds described herein).

[0038] As used herein, the term "wound" may include damage to living tissue that may occur by cutting, blows, or other impacts, typically where the skin is cut or broken. Wounds may be chronic or acute injuries. Acute wounds occur as a result of surgery or trauma. They move through stages of healing within a predictable period of time. Chronic wounds typically begin as acute wounds. Acute wounds may become chronic wounds if they do not follow the healing stages, resulting in prolonged recovery. The transition from acute to chronic wounds may be due to the patient being immunocompromised.

[0039] Chronic wounds can include, for example, venous ulcers (such as those occurring on the legs), which account for the majority of chronic wounds and primarily affect the elderly, diabetic ulcers (e.g., ulcers of the foot or ankle), peripheral arterial disease, pressure ulcers, epidermal peeling, or epidermolysis bullosa (EB).

[0040] Other examples of wounds include, but are not limited to, abdominal wounds, either as a result of surgery, trauma, sternotomy, fasciotomy, or other conditions, or other large or incisional wounds, dehiscence wounds, acute wounds, chronic wounds, subacute and dehiscence wounds, traumatic wounds, flaps and skin grafts, lacerations, abrasions, contusions, burns, diabetic ulcers, pressure ulcers, stomas, surgical wounds, traumatic ulcers, and venous ulcers.

[0041] Wounds can also include deep tissue injuries, a term proposed by the National Pressure Ulcer Advisory Panel (NPUAP) to describe a specific form of pressure ulcer. These ulcers include purple ulcers, ulcers that are likely to be exacerbated and damaged by bony prominences, and other terms have been used by clinicians to describe it for many years.

[0042] Wounds may also include tissues at risk of becoming wounds as discussed herein. For example, tissues at risk may include tissues overlying a bony prominence (at risk of deep tissue injury / injury) or pre-operative tissues (such as knee tissues) that may be amputated (e.g., for joint replacement / surgical alteration / reconstruction).

[0043] Some embodiments relate to methods of treating wounds with the technology disclosed herein in conjunction with one or more of advanced footwear, patient turning, offloading (e.g., offloading diabetic foot ulcers, etc.), treatment of infection, systemix, antimicrobials, antibiotics, surgery, tissue removal, affecting blood flow, physical therapy, exercise, bathing, nutrition, hydration, neurostimulation, ultrasound, electronic stimulation, oxygen therapy, microwave therapy, activator ozone, antibiotics, antimicrobials, and the like.

[0044] Alternatively or additionally, wounds may be treated using conventional advanced wound care that is not assisted by the use of topical and / or applied negative pressure (which may also be referred to as non-negative pressure therapy).

[0045] Advanced wound care includes the use of absorbent dressings, occlusive dressings, the use of antimicrobials and / or debridements in wound dressings or attachments, the use of padding (e.g., cushioning or compression therapy such as stockings or bandages), etc.

[0046] In some embodiments, treatment of such wounds can be performed using traditional wound care, and a dressing can be applied to the wound to facilitate and promote healing of the wound.

[0047] Some embodiments relate to a method of making a wound dressing comprising providing a wound dressing as disclosed herein.

[0048] Wound dressings that can be utilized in conjunction with the disclosed technology can include any dressing known in the art. The technology is applicable to negative pressure and non-negative pressure therapies.

[0049] In some embodiments, the wound dressing comprises one or more absorbent layers, which may be foams or superabsorbents.

[0050] In some embodiments, the wound dressing may include a dressing layer comprising a polysaccharide or modified polysaccharide, polyvinylpyrrolidone, polyvinyl alcohol, polyvinyl ether, polyurethane, polyacrylate, polyacrylamide, collagen, or gelatin, or mixtures thereof. Dressing layers comprising the listed polymers are known in the art to be useful for forming either negative pressure or non-negative pressure wound dressing layers.

[0051] In some embodiments, the polymer matrix can be a polysaccharide or a modified polysaccharide.

[0052] In some embodiments, the polymer matrix can be cellulose. Cellulosic materials include methyl cellulose, carboxymethyl cellulose (CMC), carboxymethyl cellulose (CEC), ethyl cellulose, propyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, calcocellulose, cellulose ester ... The hydrophilically modified cellulose may include a hydrophilically modified cellulose such as carboxyethyl sulfonate cellulose, a cellulose alkyl sulfonate, or a mixture thereof.

[0053] In certain embodiments, the cellulose material may be a cellulose alkyl sulfonate. The alkyl portion of the alkyl sulfate substituent may have an alkyl group having 1-6 carbon atoms, such as methyl, ethyl, propyl, or butyl. The alkyl portion may be branched or unbranched, thus a suitable propyl sulfonate substituent may be 1- or 2-methyl-ethyl sulfonate. The butyl sulfonate substituent may be 2-ethyl-ethyl sulfonate, 2,2-dimethyl-ethyl sulfonate, or 1,2-dimethyl-ethyl sulfonate. The alkyl sulfonate substituent may be ethyl sulfate. Cellulose alkyl sulfonates are described in WO 10061225, US 2016 / 114074, US 2006 / 0142560, or US 5,703,225, the disclosures of which are incorporated herein by reference in their entireties.

[0054] Cellulose alkylsulfonates can have various degrees of substitution, chain length of the cellulose backbone structure, and the structure of the alkylsulfonate substituent. Solubility and absorbency depend on the degree of substitution, and the more the degree of substitution increases, the more soluble the cellulose alkylsulfonate becomes. Increased solubility leads to increased absorbency.

[0055] In some embodiments, the wound dressing also includes a top or cover layer.

[0056] The thickness of the wound dressings disclosed herein can be from 1 to 20, or from 2 to 10, or from 3 to 7 mm.

[0057] In some embodiments, the disclosed technology can be used in conjunction with non-negative pressure dressings. Non-negative pressure wound dressings suitable for providing protection at a wound site can include:

[0058] an absorbent layer for absorbing wound exudate; and

[0059] A blocking element for at least partially blocking the visibility of wound exudate absorbed by the absorbent layer during use.

[0060] The blocking element may be partially translucent.

[0061] The blocking element may be a masking layer.

[0062] The non-negative pressure wound dressing may further include an area within or adjacent to the barrier layer to allow visualization of the absorbent layer. For example, a barrier element layer may be provided over a central region of the absorbent layer and not over a border region of the absorbent layer. In some embodiments, the barrier element is a hydrophilic material or is coated with a hydrophilic material.

[0063] The insulation element may include a three-dimensional knitted spacer fabric. Spacer fabrics are well known in the art and may include a knitted spacer fabric layer.

[0064] The blocking element may further include an indicator to indicate the need to replace the dressing.

[0065] In some embodiments, the shielding element is provided as a layer that at least partially covers the absorbent layer and that is further from the wound site than the absorbent layer during use.

[0066] The non-negative pressure wound dressing can further include a plurality of openings in the blocking element to allow fluid to travel therethrough. The blocking element may include or be coated with a material having size exclusion properties to selectively allow or prevent the passage of molecules of a given size or weight.

[0067] The blocking element may be configured to at least partially block optical radiation having wavelengths of 600 nm or less.

[0068] The blocking element can be configured to reduce light absorption by 50% or more.

[0069] The blocking element may be configured to produce a CIE L* value of 50 or greater, optionally 70 or greater. In some embodiments, the blocking element may be configured to produce a CIE L* value of 70 or greater.

[0070] In some embodiments, the non-negative pressure wound dressing may further include at least one of a wound contact layer, a foam layer, an odor control element, a pressure resistant layer, and a cover layer.

[0071] In some embodiments, a cover layer is present and the cover layer is a semi-transparent film. Typically, semi-transparent films are 500 g / m 2 / Has vapor permeability of more than 24 hours.

[0072] The translucent film can be a bacterial barrier.

[0073] In some embodiments, the non-negative pressure wound dressing disclosed herein comprises a wound contact layer, and an absorbent layer overlies the wound contact layer, the wound contact layer carrying an adhesive portion for forming a substantially fluid-tight seal over the wound site.

[0074] The non-negative pressure wound dressings disclosed herein can comprise a barrier element and an absorbent layer provided as a single layer.

[0075] In some embodiments, the non-negative pressure wound dressings disclosed herein include a foam layer and the blocking element is a material that includes components that may become displaced or damaged by movement of the blocking element.

[0076] In some embodiments, the non-negative pressure wound dressing includes an odor control element, while in other embodiments the dressing does not include an odor control element. When present, the odor control element may be dispersed within or adjacent to the absorbent layer or barrier element. Alternatively, when present, the odor control element may be provided as a layer sandwiched between the foam layer and the absorbent layer.

[0077] In some embodiments, the disclosed technology for non-negative pressure wound dressings includes a method of manufacturing a wound dressing, the method including providing an absorbent layer for absorbing wound exudate and providing a blocking element for at least partially blocking visibility of wound exudate absorbed by the absorbent layer during use.

[0078] In some embodiments, a non-negative pressure wound dressing may be suitable for providing protection to a wound site and includes an absorbent layer for absorbing wound exudate, and a shielding layer provided over the absorbent layer and further from the wound-facing side of the wound dressing than the absorbent layer. The shielding layer may be provided directly on the absorbent layer. In some embodiments, the shielding layer includes a three-dimensional spacer fabric layer.

[0079] The shielding layer increases the area across which a pressure applied to the coating is transmitted by at least 25% of the area across which the pressure was initially applied, for example, the shielding layer increases the area across which a pressure applied to the coating is transmitted by at least 50%, optionally at least 100%, optionally at least 200%.

[0080] The shielding layer can include two or more sublayers, a first sublayer comprising a through hole and a further sublayer comprising a through hole, the through hole of the first sublayer being offset from the through hole of the further sublayer.

[0081] The non-negative pressure wound dressings disclosed herein may further include a permeable cover layer for allowing gases and vapors to permeate therethrough, the cover layer being provided over the shield layer, the perforations of the cover layer being offset from the perforations of the shield layer.

[0082] Non-negative pressure wound dressings may be suitable for treating pressure ulcers.

[0083] A more detailed description of the previously disclosed non-negative pressure dressings is provided in International Patent Application Publication No. WO2013 / 007973, which is incorporated herein by reference in its entirety.

[0084] In some embodiments, the non-negative pressure wound dressing may be a multi-layer wound dressing comprising a fibrous absorbent layer for absorbing exudate from the wound site and a support layer configured to reduce contraction of at least a portion of the wound dressing.

[0085] In some embodiments, the multi-layer wound dressing disclosed herein further comprises a liquid impermeable film layer, and the support layer is disposed between the absorbent layer and the film layer.

[0086] The support layer disclosed herein may include a net. The net may include a geometric structure having a plurality of substantially geometric openings extending therethrough. The geometric structure may include, for example, a plurality of protrusions substantially evenly spaced and connected by polymer chains to form substantially geometric openings between the polymer chains.

[0087] The netting may be formed from high density polyethylene.

[0088] The opening is 0.005 to 0.32 mm. 2 may have an area of

[0089] The support layer may have a tensile strength of 0.05 to 0.06 nm.

[0090] The support layer may have a thickness of from 50 to 150 μm.

[0091] In some embodiments, the support layer is disposed directly adjacent to the absorbent layer. Typically, the support layer is bonded to the fibers on the top surface of the absorbent layer. The support layer may further comprise a bonding layer, where the support layer is laminated to the fibers in the absorbent layer via the bonding layer. The bonding layer may include a low melting adhesive, such as an ethylene vinyl acetate adhesive.

[0092] In some embodiments, the multi-layer wound dressing disclosed herein further comprises an adhesive layer attaching the film layer to the backing layer.

[0093] In some embodiments, the multi-layer wound dressing disclosed herein further comprises a wound contact layer disposed adjacent to the absorbent layer for positioning adjacent the wound. The multi-layer wound dressing may further comprise a fluid transport layer between the wound contact layer and the absorbent layer for transferring exudate from the wound to the absorbent layer.

[0094] A more detailed description of the previously disclosed multi-layer wound dressing is provided in UK Patent Application No. GB1618298.2, filed on 28 October 2016, which is incorporated herein by reference in its entirety.

[0095] In some embodiments, the disclosed technology can be incorporated into a wound dressing comprising vertically layered materials, the wound dressing comprising a first layer of absorbent material and a second layer of material, the first layer being constructed from at least one layer of nonwoven textile fabric, the nonwoven textile fabric being folded into a plurality of folds to form a pleated structure. In some embodiments, the wound dressing further comprises a second layer of material temporarily or permanently bonded to the first layer of material.

[0096] Typically the vertically folded material is cut into strips.

[0097] In some embodiments, the first layer has a pleated structure with a depth determined by the pleat depth or by the cut width. The first layer of material can be a molded, lightweight, fiber-based material, blend of materials or a composition layer.

[0098] The first layer of material can include one or more fibers made from synthetic, natural, or inorganic polymers, natural fibers of natural cellulosic, proteinaceous, or mineral sources.

[0099] The wound dressing may comprise two or more layers of absorbent material layers folded vertically one on top of the other, the two or more layers having the same or different densities or compositions.

[0100] The wound dressing may, in some embodiments, comprise only one layer of absorbent material layer of vertically folded material.

[0101] The absorbent material layer is a blend of natural or synthetic fibers, organic or inorganic fibers, and binder fibers, or a bicomponent fiber, typically PET with a low melting temperature PET coating, so that it softens at a specified temperature and acts as a binding agent for the blend.

[0102] In some embodiments, the absorbent layer of material may be a blend of 5-95% thermoplastic polymer and 5-95% by weight cellulose or its derivatives.

[0103] In some embodiments, the wounds disclosed herein have a second layer comprising a foam or dressing fixative.

[0104] The foam may be a polyurethane foam, which may have an open or closed pore structure.

[0105] The dressing fixative may include a bandage, tape, gauze, or a backing layer.

[0106] In some embodiments, the wound dressings disclosed herein comprise an absorbent material layer connected directly to a second layer by lamination or by an adhesive, which is connected to the dressing fixative layer. The adhesive can be an acrylic adhesive or a silicone adhesive.

[0107] In some embodiments, the wound dressings disclosed herein further comprise a layer of superabsorbent fibers, or viscose or polyester fibers.

[0108] In some embodiments, the wound dressing disclosed herein further comprises a backing layer. The backing layer can be a transparent or opaque film. Typically, the backing layer comprises a polyurethane film, typically a transparent polyurethane film.

[0109] A more detailed description of the previously disclosed multi-layer wound dressing is provided in UK Patent Application No. GB1621057.7, filed December 12, 2016, and UK Patent Application No. GB1709987.0, filed June 22, 2017, each of which is incorporated by reference in its entirety.

[0110] In some embodiments, a non-negative pressure wound dressing can include an absorbent component for the wound dressing, the component comprising a wound contact layer including gel-forming fibers bonded to a foam layer, the foam layer being bonded directly to the wound contact layer by adhesive, a polymer-based melt layer, flame lamination, or ultrasonics.

[0111] The absorbent component may be in sheet form.

[0112] The wound contact layer may comprise a layer of woven, or non-woven, or knit gel-forming fibers.

[0113] The foam layer may be an open cell foam or a closed cell foam, typically an open cell foam. The foam layer is a hydrophilic foam.

[0114] The wound dressing may include components that form islands of direct wound contact surrounded by a perimeter of adhesive that adheres the dressing to the wound. The adhesive may be a silicone or acrylic adhesive, typically a silicone adhesive.

[0115] The wound dressing may be covered by a film layer on the surface of the dressing furthest from the wound.

[0116] A more detailed description of this type of wound dressing is provided in European Patent No. EP2498829, which is incorporated herein by reference in its entirety.

[0117] In some embodiments, a non-negative pressure wound dressing may include a multi-layer wound dressing for use on wounds producing high levels of exudate, the dressing comprising a transmission layer having an MVTR of at least 300 gm2 / 24 hr, an absorbent core comprising gel-forming fibers capable of absorbing and retaining exudate, a wound contact layer comprising gel-forming fibers that transmits exudate to the absorbent core, and a keying layer positioned on the absorbent core, the absorbent core and wound contact layer being characterized in that they limit the lateral spread of exudate into the wound area of ​​the dressing.

[0118] Wound dressing should be 10cm in 24 hours. 2 It may be possible to handle at least 6g (or 8g and 15g) of fluid per dressing.

[0119] The wound dressing may comprise gel-forming fibres which are chemically modified cellulose fibres in the form of a woven fabric. The fibres may comprise carboxymethyl cellulose fibres, typically sodium carboxymethylated cellulose fibres.

[0120] The wound dressing may include a wound contact layer having a lateral wicking rate of between 5 mm / min and 40 mm / min. The wound contact layer may be 35 gm 2 etc., 25gm 2 ~55gm 2 The fiber density may be

[0121] The absorbent core may have an absorbency of at least 10 g / g of exudate, and typically a lateral wicking rate of less than 20 mm / min.

[0122] The absorbent core may have a blend of up to 25% by weight cellulosic fibers and gel-forming fibers ranging from 75% to 100% by weight.

[0123] Alternatively, the absorbent core may have a blend of up to 50% by weight cellulosic fibers and in the range of 50% to 100% by weight gel-forming fibers, for example, the mixture is in the range of 50% by weight cellulosic fibers and 50% by weight gel-forming fibers.

[0124] The fiber density of the absorbent core is 150 gm 2 ~250gm 2 , or about 200 gm 2 It could be.

[0125] The wound dressing may have a shrinkage of less than 25% or less than 15% of its original size when wet.

[0126] The wound dressing may include a transmission layer, which is a foam. The transmission layer may be a polyurethane foam laminated to a polyurethane film.

[0127] The wound dressing may include one or more layers selected from the group consisting of a soluble medicated film layer, an odor absorbing layer, a dispersion layer, and an additional adhesive layer.

[0128] The wound dressings are available in thicknesses of 2mm and 4mm.

[0129] The wound dressing may be characterized by a keying layer that bonds the absorbent core to an adjacent layer. In some embodiments, the keying layer may be positioned on either the wound-facing side of the absorbent core or the non-wound-facing side of the absorbent core. In some embodiments, the keying layer is positioned between the absorbent core and the wound contact layer. The keying layer is a polyamide web.

[0130] A more detailed description of this type of wound dressing is provided in European Patent No. EP1718257, which is incorporated herein by reference in its entirety.

[0131] In some embodiments, the non-negative pressure wound dressing can be a compression bandage. Compression bandages are well known for use in treating edema and other venous disorders, as well as lymphatic disorders of the lower extremities.

[0132] Compression bandage systems typically employ multiple layers, including a padding layer between the skin and one or more compression layers. Compression bandages can be useful on wounds, such as to treat venous leg ulcers.

[0133] The compression bandage, in some embodiments, can comprise a bandage system including a skin-facing inner layer and an elastic outer layer, the inner layer including a first layer of foam and a second layer of a moisture-wicking nonwoven web, the inner and outer layers being sufficiently stretchable to be wrapped around a patient's limb. A compression bandage of this type is disclosed in International Patent Publication No. WO 99 / 58090, the entirety of which is incorporated herein by reference.

[0134] In some embodiments, the compression bandage system comprises: a) an inner, skin-facing, elongate elastic bandage comprising: (i) an elongate elastic substrate;

[0135] (ii) an elongated elastic bandage comprising an elongated foam layer attached to a surface of a substrate and extending laterally across at least 33% of the surface of the substrate and extending longitudinally across at least 67% of the surface of the substrate, and b) an outer elongated adhesive elastic bandage having a compressive force when stretched, wherein in use the foam layer of the inner bandage faces the skin and the outer bandage overlies the inner bandage. A compression bandage of this type is disclosed in WO 2006 / 110527, the entire contents of which are incorporated herein by reference.

[0136] In some embodiments, other compression bandage systems, such as those disclosed in US Pat. No. 6,759,566 and US Patent Application Publication No. 2002 / 0099318, each of which is incorporated herein by reference in its entirety.

[0137] Negative pressure wound dressings In some embodiments, the treatment of such wounds may be performed using negative pressure wound therapy, where reduced or negative pressure may be applied to the wound to facilitate and promote healing of the wound. It will also be understood that the wound dressings and methods disclosed herein may be applied to other parts of the body and are not necessarily limited to the treatment of wounds.

[0138] It will be understood that embodiments of the present disclosure are generally applicable for use with topical negative pressure ("TNP") treatment systems. In brief, negative pressure wound therapy may assist in closing and healing many forms of "difficult to heal" wounds by reducing tissue edema, encouraging blood flow and granular tissue formation, and removing excessive exudate, reducing bacterial load (and therefore infection risk). In addition, treatment may reduce wound unrest, leading to faster healing. TNP therapy systems may also assist in the healing of surgically closed wounds by removing fluids and helping to stabilize tissues in an apposed position of closure. Further beneficial uses of TNP therapy may be found in grafts and flaps, where removing excess fluids is important and grafts are required to be in close proximity to tissue to ensure tissue viability.

[0139] Negative pressure therapy can be used to treat open or chronic wounds that are too large to close naturally or that cannot be healed by applying negative pressure to the wound site. Topical negative pressure (TNP) therapy, or negative pressure wound therapy (NPWT), involves placing a fluid-impermeable or semi-permeable covering over the wound, using various means to seal the covering against the patient's tissue surrounding the wound, and connecting a negative pressure source (such as a vacuum pump) to the covering in such a way that a negative pressure is created and maintained beneath the covering. Such negative pressure is believed to promote wound healing by facilitating the formation of granulation tissue at the wound site and supporting normal internal inflammatory processes while simultaneously removing excess fluid, which may contain harmful cytokines or bacteria.

[0140] Some of the dressings used in NPWT can include many different types of materials and layers, such as gauze, pads, foam pads, or multi-layer wound dressings. One example of a multi-layer wound dressing is the PICO dressing available from Smith & Nephew, which includes a wound contact layer and a superabsorbent layer below a backing layer to provide a canister-free system for treating wounds with NPWT. The wound dressing can be sealed with a suction port that provides a connection to a long tube that can be used to pump fluid from the dressing or transfer negative pressure from a pump to the wound dressing. In addition, RENASYS-F, RENASYS-G, RENASYS-AB, and RENASYS-F / AB available from Smith & Nephew are further examples of NPWT wound dressings and systems. Another example of a multi-layer wound dressing is the ALLEV® dressing available from Smith & Nephew, which includes a moist wound environment dressing used to treat wounds without the use of negative pressure. It is a YN Life covering material.

[0141] As used herein, a reduced pressure or negative pressure level, such as -XmmHg, represents a pressure relative to normal ambient atmospheric pressure, which may correspond to 760mmHg (or 1 atm, 29.93 inHg, 101.325 kPa, 14.696 psi, etc.). Thus, a negative pressure value of -XmmHg reflects an absolute pressure of XmmHg less than 760mmHg, or in other words, an absolute pressure of (760-X)mmHg. In addition, a negative pressure "lower" or "smaller" than XmmHg corresponds to a pressure closer to atmospheric pressure (e.g., -40mmHg is lower than -60mmHg). A negative pressure "higher" or "larger" than -XmmHg corresponds to a pressure further away from atmospheric pressure (e.g., -80mmHg is higher than -60mmHg). In some embodiments, the local ambient atmospheric pressure is used as a reference point, and such local atmospheric pressure may not necessarily be, for example, 760mmHg.

[0142] The negative pressure range of some embodiments of the present disclosure may be about -80 mmHg, or about -20 mmHg to -200 mmHg. Note that these pressures are relative to normal ambient atmospheric pressure, which may be 760 mmHg. Therefore, -200 mmHg would be substantially about 560 mmHg. In some embodiments, the pressure range may be between about -40 mmHg and -150 mmHg. Alternatively, a pressure range of up to -75 mmHg, up to -80 mmHg, or greater than -80 mmHg may be used. Also, in other embodiments, a pressure range below -75 mmHg may be used. Alternatively, a pressure range of approximately -100 mmHg or even above -150 mmHg may be provided by the negative pressure device.

[0143] In some embodiments of the wound closure devices described herein, increased wound contraction can lead to increased tissue expansion in the surrounding wound tissue. This effect can be increased by varying the force applied to the tissue, for example, varying the negative pressure applied to the wound over time, in conjunction with the increased tensile force applied to the wound by the wound closure device embodiments. In some embodiments, the negative pressure can be varied over time, for example, using a sine wave, a square wave, or in synchronization with one or more patient physiological indicators (such as heart rate). Examples of such applications, further disclosure of which can be found in the foregoing, include U.S. Patent No. 8,235,955, entitled "Wound treatment apparatus and method," issued on August 7, 2012, and U.S. Patent No. 7,753,894, entitled "Wound cleansing apparatus with stress," issued on July 13, 2010. The disclosures of both of these patents are incorporated herein by reference in their entirety.

[0144]

[0023] Embodiments of the wound dressings, wound dressing components, wound treatment devices, and methods described herein may also be used in combination with, or in addition to, International Patent Application No. PCT / IB2013 / 001469, filed May 22, 2013, and published November 28, 2013 as International Patent Application Publication No. WO2013 / 175306 A2, entitled "APPARATUSES AND METHODS FOR NEGATIVE PRESSURE WOUND THERAPY," and U.S. Patent Application No. 14 / 418,908, filed January 30, 2015, and published July 9, 2015 as U.S. Patent Application Publication No. US2015 / 0190286, entitled "WOUND DRESSING AND METHOD OF TREATMENT," the disclosures of which are incorporated herein by reference in their entireties. Embodiments of the wound dressings, wound dressing components, wound treatment devices, and methods described herein are also disclosed in U.S. patent application Ser. No. 13 / 092,042, filed Apr. 21, 2011, and published as U.S. Patent Application Publication No. US2011 / 0282309, entitled "WOUND DRESSING AND METHOD OF USE," and U.S. patent application Ser. No. 14 / 715,522, filed May 18, 2015, and published as U.S. Patent Application Publication No. US2011 / 0282309. No. 6,339,757, filed on Nov. 24, 2016 as U.S. Patent Application Publication No. US2016 / 0339158 A1, entitled "FLUIDIC CONNECTOR FOR NEGATIVE PRESSURE WOUND THERAPY," the disclosures of which are incorporated herein by reference in their entireties, including details regarding wound dressings, components and principles of wound dressings, and embodiments of materials used in wound dressings.

[0145] Additionally, some embodiments relating to TNP wound treatment including wound dressings in combination with pumps or associated electronics described herein may also be used in combination with or in addition to International Patent Application No. PCT / EP2016 / 059329, filed April 26, 2016, and published November 3, 2016 as International Patent Application Publication No. WO2016 / 174048, entitled "REDUCED PRESSURE APPARATUS AND METHODS," the disclosures of which are incorporated herein by reference in their entireties.

[0146] Wound Therapy System Overview FIG. 1 illustrates an embodiment of a negative pressure or reduced pressure wound therapy (or TNP) system 100 comprising a wound packing 130 disposed within a wound cavity 110, the wound cavity being sealed by a wound cover 120. The wound packing 130 combined with the wound cover 120 may be referred to as a wound dressing. A single or multiple lumen tube or conduit 140 connects the wound cover 120 to a pump assembly 150 configured to provide reduced pressure. The wound cover 120 may be in fluid communication with the wound cavity 110. In any of the system embodiments disclosed herein, such as the embodiment illustrated in FIG. 1, the pump assembly may be a canisterless pump assembly (meaning that exudate is collected in the wound dressing or transferred to another location via the tube 140 for collection). However, some pump assembly embodiments disclosed herein may be configured to include or support a canister. Additionally, in some system embodiments disclosed herein, some pump assembly embodiments may be attached to or supported by a covering or adjacent to a covering.

[0147] The wound packing 130 can be of any suitable type, such as hydrophilic or hydrophobic foam, gauze, an inflatable bag, etc. The wound packing 130 can conform to the wound cavity 110 such that it substantially fills the cavity. The wound cover 120 can provide a substantially fluid-impermeable seal over the wound cavity 110. The wound cover 120 can have a top side and a bottom side, where the bottom side adhesively (or in any other suitable manner) seals the wound cavity 110. The conduit 140 or lumen disclosed herein or some other conduit or lumen can be formed from polyurethane, PVC, nylon, polyethylene, silicone, or any other suitable material.

[0148] Some embodiments of the wound cover 120 may have a port (not shown) configured to receive an end of the conduit 140. For example, the port can be a Renays Soft Port available from Smith & Nephew. In other embodiments, the conduit 140 can otherwise pass through or under the wound cover 120 to supply reduced pressure to the wound cavity 110 to maintain a desired level of reduced pressure within the wound cavity. The conduit 140 can be any suitable article configured to provide at least a substantially sealed fluid flow path between the pump assembly 150 and the wound cover 120 to supply reduced pressure provided by the pump assembly 150 to the wound cavity 110.

[0149] The wound cover 120 and wound packing 130 may be provided as a single article or integral single unit. In some embodiments, no wound packing is provided and the wound cover 120 may be considered the wound dressing alone. The wound dressing may then be connected via conduit 140 to a source of negative pressure, such as a pump assembly 150. The pump assembly 150 may be miniaturized and portable, although larger conventional such pumps may also be used.

[0150] The wound cover 120 can be placed over the wound site to be treated. The wound cover 120 can form a substantially sealed cavity or enclosure that covers the wound site. In some embodiments, the wound cover 120 can be configured to have a film with high water vapor permeability to allow evaporation of excess fluids and can have a superabsorbent material contained therein to safely absorb wound exudate.

[0151] The pump assembly 150 may be configured to provide a negative pressure of approximately -80 mmHg, or between about -20 mmHg and 200 mmHg in some implementations. Note that these pressures are relative to normal ambient atmospheric pressure, i.e., -200 mmHg may be approximately 560 mmHg in practical terms. The pressure range may be between approximately -40 mmHg and -150 mmHg. Alternatively, a pressure range up to -75 mmHg, up to -80 mmHg, or greater than -80 mmHg may be used. Also, a pressure range below -75 mmHg may be used. Alternatively, a pressure range of approximately -100 mmHg or even above 150 mmHg may be provided by the pump assembly 150.

[0152] In operation, the wound filler 130 is inserted into the wound cavity 110 and the wound cover 120 is positioned to seal the wound cavity 110. The pump assembly 150 provides a source of negative pressure to the wound cover 120 that is delivered to the wound cavity 110 through the wound filler 130. Fluid (e.g., wound exudate) may be drawn through the conduit 140 and stored in the canister. In some embodiments, the fluid is absorbed by the wound filler 130 or one or more absorbent layers (not shown).

[0153] Overview of wound dressings FIG. 2 illustrates a cross-sectional view of a wound dressing 200, which may be similar or the same as the wound cover 120 and wound packing 130 of FIG. 1, with a fluid connector 204 that may be similar to the conduit 140 of FIG. 1. The wound dressing 200 may include a top or cover layer, or a backing layer 220, attached to a wound contact layer 222, which may be bonded or sealed together to define an interior space or chamber. This interior space or chamber may include additional structures that may be adapted to distribute or transmit negative pressure, store wound exudate and other fluids removed from the wound, as well as perform other functions. Examples of such structures include the permeable layer 226 and absorbent layer 221 described herein. Additionally, one or more sensors 250, which may be part of a sensor array, may be incorporated on or into the wound dressing 200, such as the wound contact layer 222 shown.

[0154] As used herein, the top, upper or upper layer refers to the layer that is furthest from the skin or wound surface while the dressing is in use and over the wound, and the lower, lower, bottom or lower layer thus refers to the layer that is closest to the skin or wound surface while the dressing is in use and over the wound.

[0155] The wound contact layer 222 has a lower surface 224 (e.g., facing the wound) and an upper surface 223 (e.g., facing away from the wound). The perforations 225 may include through holes in the wound contact layer 222 that allow fluid to flow through the wound contact layer 222. 222 helps prevent tissue ingrowth into the other materials of the wound dressing 200.

[0156] A porous layer 226 of porous material may be disposed on top of the wound contact layer 222. This porous layer, or permeable layer 226, allows fluids, including liquids and gases, to permeate from the wound site through the upper layers of the wound dressing 200. In particular, the permeable layer 226 may ensure that outside air channels may be maintained to convey negative pressure throughout the wound area, even when the absorbent layer has absorbed a significant amount of exudate.

[0157] A layer 221 of absorbent material is provided on top of the transmission layer 226. The absorbent material, which may include foam or nonwoven natural or synthetic materials, and may optionally include superabsorbent materials, forms a reservoir for fluids, particularly liquids, that are removed from the wound site. In some embodiments, layer 221 may also help draw fluids toward the backing layer 220.

[0158] An opening, hole, or orifice 227 is provided in the backing layer 220 to allow negative pressure to be applied to the wound dressing 200. A fluid connector 204 can be attached or sealed to the top of the backing layer 220 above the orifice 227 to the wound dressing 200 and transmits the negative pressure through the orifice 227.

[0159] In some embodiments, the absorbent layer 221 includes at least one through hole 228 arranged to be under the fluid connector 204. The through hole 228 may be the same size as the opening 227 in the backing layer, or may be larger or smaller. An opening or through hole 228 may be provided in the absorbent layer 221 under the orifice 227 such that the orifice is directly connected to the transmission layer 226. This allows negative pressure applied to the fluid connector 204 to be transmitted to the transmission layer 226 without passing through the absorbent layer 221. This ensures that negative pressure applied to the wound site is not inhibited by the absorbent layer as it absorbs wound exudate. In other embodiments, no opening may be provided in the absorbent layer 221, or alternatively, multiple openings under the orifice 227 may be provided.

[0160] Referring now to the fluid connector 204, some embodiments include a sealing surface 216, a bridge 211 having a proximal end 230 and a distal end 240, and a filter 214. The sealing surface 216 can form the applicator described above that is sealed to the upper surface of the wound dressing 200. The bottom layer of the fluid connector 204 can include the sealing surface 216. The fluid connector 204 can further include an upper surface vertically spaced apart from the sealing surface 216, which in some embodiments is defined by a separate upper layer of the fluid connector 204. In other embodiments, the upper and lower surfaces can be formed from the same piece of material. In some embodiments, the sealing surface 216 can include at least one opening 229 therein to communicate with the wound dressing 200.

[0161] The bridge 211 can include a first fluid passageway 212 in communication with a negative pressure source, the first fluid passageway 212 including a porous material, such as a 3D knit material, that can be the same or different as the porous layer 226. The bridge 211 can have a proximal end and a distal end and can be encapsulated by at least one flexible film layer 208, 210 configured to surround the first fluid passageway 212, the distal end of the flexible film connecting to the sealing surface 216. The filter 214 is configured to substantially prevent wound exudate from entering the bridge.

[0162] Sensor-enabled wound dressing A wound dressing, such as wound dressing 200 of FIG. 2, can incorporate a number of sensors or sensors, such as one or more sensors 250 of FIG. The sensor may be used in one or more components that form part of the covering or total wound dressing device. For example, the sensor may be incorporated on or in a wound contact layer or sheet, such as wound contact layer 222 of FIG. 2, that may be placed in contact with the wound and allow fluid to pass through while causing little or no damage to the tissue within the wound. The sensor-integrated wound contact layer or sheet may be made of a flexible material, such as silicone, and may incorporate antimicrobial substances or other therapeutic agents. The sensor-integrated wound contact layer or sheet may incorporate an adhesive that adheres to wet or dry tissue. In still other implementations, the sensor may additionally or alternatively be incorporated or encapsulated in other components of the wound dressing, such as an absorbent layer or spacer layer.

[0163] In some implementations, the one or more sensors may include sensors for temperature (25 thermistor sensors, 5×5 array, ∼20 mm pitch, etc.), pulse oximetry or SpO2 (4 or 5 SpO2 sensors, single line from center of wound contact layer to its edge, 10 mm pitch, etc.), optical properties of tissue, exudate, or foreign body (10 optical sensors, 2×5 array, ∼20 mm or less pitch, etc.; not all 5 sensors in each row of the array need to be aligned), pH (by measuring the color of a pH sensitive pad, optionally using the same optical sensor as the tissue color, etc.), and conductivity (e.g., 9 conductive contacts, 3×3 array, ∼40 mm pitch, etc.). Additionally or alternatively, other sensors such as pressure, flow, strain, colorimetric sensors configured to measure biological or chemical compounds (e.g., dye-coated colorimetric sensors), or the like, may be used. Colorimetric sensors may be used to measure odor, toxicity, etc. Any one or more sensors described herein may be placed or positioned to obtain measurements anywhere on the wound or skin.

[0164] The sensors may be supported by or incorporated into a flexible or substantially flexible substrate, such as one or more of a flexible or substantially flexible printed circuit (FPC), which may be formed from flexible polymers including polyamide, polyimide (PI), polyester, polyethylene naphthalate (PEN), polyetherimide (PEI), polyurethane, thermoplastic polyurethane (TPU), in addition to various fluoropolymers (FEP) and copolymers, or any other suitable material. The substantially flexible or flexible substrate may include single-sided, double-sided, or multi-layer circuits. In some implementations, the sensor array may be incorporated into a two-layer flexible circuit. In some embodiments, the FPC may be a multi-layer flexible printed circuit. In some embodiments, these flexible printed circuits may be incorporated into any layer of the wound dressing. In some embodiments, the flexible circuit may be incorporated into the wound contact layer (e.g., may be located on or in the wound contact layer). For example, the flexible circuit may be incorporated into a wound contact layer similar to the wound contact layer described with reference to Figure 2. The wound contact layer may have cutouts or slits that allow one or more sensors to protrude from the lower surface of the wound contact layer and directly contact the wound area.

[0165] The sensor-integrated wound contact layer may include a first and a second wound contact layer with an FPC sandwiched between two layers of wound contact layer material. The first wound contact layer has a lower surface intended to contact the wound and an upper surface intended to contact the FPC. The second wound contact layer has a lower surface intended to contact the FPC and an upper surface intended to contact the wound dressing or one or more components forming part of the overall wound dressing device. The upper surface of the first wound contact layer and the lower surface of the second wound contact layer may be bonded together with the FPC sandwiched between the two layers.

[0166] FIG. 3A includes a sensor portion 301, a tail portion 302, and a connector pad end portion 303. 2. The sensor array 300 includes a tail portion 302 that extends from the sensor portion 301 to a connector pad end portion 303 that can electrically or electronically connect to a control module or other processing unit to receive data from the sensor portion 301. The sensor array 300 can be incorporated onto or into a wound dressing, such as the wound dressing 200 of FIG. 2, such as within the wound contact layer 222 of the wound dressing 200.

[0167] FIG. 3B illustrates the sensor portion 301 of the sensor array 300 of FIG. 3A according to some embodiments. The sensor portion 301 can include multiple portions that extend around the periphery of a wound dressing component, such as a wound contact layer, or inward from the outer edge of the wound dressing component. For example, the embodiment illustrated in FIG. 3B includes multiple linearly extending portions that are parallel to the edge of the wound dressing component and, in some embodiments, can trace the entire circumference of the wound dressing component. In some embodiments, the sensor portion 301 can comprise a first multiple parallel linearly extending portions that are perpendicular to a second multiple parallel linearly extending portions. These linearly extending portions may also have different lengths and extend inwardly to different locations within the interior of the wound dressing component. In some embodiments, the sensor portion 301 does not cover the entire wound dressing component, and gaps are formed between portions of the sensor array 300.

[0168] As can be seen in FIG. 3B, one or more temperature sensors, impedance sensors (or conductivity sensors), SpO2 sensors, or optical, ultraviolet (UV), infrared (IR), or other types of visible or invisible light sensors can be used in a sensor array to provide information about the condition of the wound. Optical, ultraviolet (UV), infrared (IR), or other types of visible or invisible light sensors, or other electromagnetic spectrum sensors, can provide spectral measurements of the wound. One or more sensors can assist the clinician in monitoring wound healing and can operate independently or in combination with each other to provide data about the characteristics of the wound and wound healing.

[0169] Impedance sensors can be used, for example, to determine the difference between live and dead tissue, or to indicate changes in impedance due to opening a wound in diseased tissue. Impedance sensors can include Ag / AgCl electrodes and impedance analyzers. Impedance sensors can be used to measure changes in impedance in wounded areas, for example, by measuring the impedance of the surrounding tissue / area. Impedance sensors can also be used at the wound bed or at the periphery of the wound, or to detect failure of dressing adhesion.

[0170] The sensor portion 301, in some implementations, can utilize impedance sensors to measure changes in impedance of peripheral electrodes due to changes in wound size or wound shape. For example, tomographic reconstruction or tomography can be used to infer wound size by using differently spaced impedance sensors or electrodes. Voltage or current probes can be used to apply voltage or current stimuli to determine or test the patient's neural response or to promote wound healing. Impedance can be measured in a conductive path through a biocompatible layer (e.g., of a wound dressing) or through a biocompatible gel layer (e.g., a conductive gel layer) or saline solution in contact with the wound. Measurements can be made in the frequency range of about 2.5 kHz to about 100 kHz. This can be similar to the use of large patch clamp measurements.

[0171] Alternatively or additionally, the impedance can be measured using a capacitive or capacitive coupling method without making direct contact with the tissue (e.g., using non-contact electrodes). For example, transmission in the frequency range of about 30 kHz to about 70 kHz can be used. The impedance can be measured using a three-point probe measurement or a four-point probe measurement. One or more impedances of the wound tissue or exudate can be measured and used to infer cell or tissue health. The impedance of the area around the wound (such as the skin or tissue surrounding the wound) can be measured. The impedance sensor can be retractable to move in and out as needed. The impedance sensor can include a fine or microprobe needle with a conductive tip that extends into the wound and an insulating shaft. The impedance sensor can be a suspended probe that is directly under the wound contact layer that contacts the wound. The impedance sensor can include a dry contact electrode. The impedance sensor can include electrodes that ensure or promote biocompatibility, such as gold, silver, platinum or carbon electrodes.

[0172] In certain embodiments, a controller (such as a microprocessor) can be attached to the wound dressing and connected to one or more sensors. The controller so mounted can communicate with the control module by a connection such as a three or four wired connection (or fewer or more) to reduce the load associated with connecting to external components. For example, the tail portion 302 can include three or four wired connections. In some implementations, the mounted controller can communicate wirelessly.

[0173] A controller or control module can be used to interface with the sensor array 300. The control module can include a power source, such as a battery, and electronics to drive the sensors. The control module can also log data at appropriate intervals and allow data transfer to an external computing device, such as a personal computer (PC). The control module can be customized with various features depending on the sensors used in the sensor array 300 and the data collected by the sensors. The control module can be comfortable and small enough to be worn continuously for several weeks and can be located near or on the wound dressing. In some embodiments, the control module can be located remotely from the wound dressing and associated sensor array 300. Whether the control module is located on the dressing, near the dressing, or remotely from the wound dressing, it can communicate with the sensor array 300 and wound dressing through electrical wires or through wireless communication. In some embodiments, the control module may determine a characteristic of the wound from the data collected by the sensor array 300 and activate an alarm in response to the characteristic, such as to indicate that dead tissue has been detected.

[0174] The control module may include various requirements and combinations of features, including but not limited to the features listed in Table 1 below.

[0175] [Table 1]

[0176] 3C illustrates a block diagram of a control module 390 according to some embodiments. The control module 390 includes an impedance driver box 391 that supports impedance driver features. Box 392 supports temperature sensor (e.g., thermistor) interface features, and box 393 supports optical interface features. The control module 390 can include a controller or microprocessor 394 having features including a real-time clock (RTC), status LEDs, a USB connector, serial flash, and a debug connector.

[0177] The control module may include a memory component, with the amount of local storage dependent on the sampling rate and resolution of the sensor. The control module may utilize one or more analog switches. The control module may incorporate a power source, such as a battery, or may alternatively utilize a power source separate from the control module. The control module may incorporate a real-time clock (RTC). The control module's printed circuit board (PCB) may be a four-layer board, approximately 50 mm x 20 mm, or 25 mm x 40 mm. The type of PCB used may be driven in large part by the connection requirements to the sensor array.

[0178] Data collected through the sensor array can be passed through the control module and processed by the host software. The software may be executed on a processing device. The processing device may be a PC, a tablet-type computing device or tablet, a smart phone, or other computer (e.g., a custom computing device) capable of running the host software. The processing device running the software may communicate with the control module through wires or by wireless communication.

[0179] The electronics, including one or more sensors or control modules, can be constructed to be compatible or safe for x-ray, MRI, or other types of manipulation. The electronics can be constructed to be compatible or safe for use with external or implantable defibrillators. The electronics can include protection against radio frequency interference (RFI) or electromagnetic interference (EMI). For example, one can be made from ferrite, copper, or another material. The following EMI shields may be used: Faraday cages or similar.

[0180] In some embodiments, a negative pressure source, such as a pump, and some or all other components of a local negative pressure system, such as power source(s), sensor(s), connector(s), user interface component(s) (button(s), switch(es), speaker(s), screen(s), etc.), may be integrated with the wound dressing. In some embodiments, the components may be integrated below, within, on, or adjacent to the top of the backing layer. In some embodiments, the wound dressing may include a positioning second cover layer or a second filter layer over any of the layers of the wound dressing and the integrated components. The second cover layer may be the top layer of the dressing or may be a separate skin that surrounded the integrated components of the local negative pressure system.

[0181] Component placement In some embodiments, electrical or electronic components such as sensors, connections, etc. can be disposed or positioned on or incorporated into one or more wound dressing components that can be disposed in or on the wound, the skin, or both the wound and the skin. For example, one or more electronic components can be positioned on the side of the wound contact layer that faces the wound, such as the lower surface 224 of the wound contact layer 222 in FIG. 2. The wound contact layer may be flexible, elastic, or stretchable, or substantially flexible, elastic, or stretchable to conform to or cover the wound. For example, the wound contact layer can be made from a stretchable or substantially stretchable material such as one or more of polyurethane, thermoplastic polyurethane (TPU), silicone, polycarbonate, polyethylene, polyimide, polyamide, polyester, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), polyetherimide (PEI), along with various fluoropolymers (FEP) and copolymers, or another suitable material. In some instances, one or more electronic components may alternatively, or additionally, be positioned or embedded in any one or more of the transmission layer, the absorbent layer, the backing layer, or any other suitable layer of the wound dressing.

[0182] In some embodiments, it may be desirable for the wound contact layer to be stretchable so as to better conform to or cover the wound, although at least some of the electronic components may not be stretchable or flexible. In such cases, when the wound is covered with the wound dressing and the wound contact layer is positioned in or on the wound, undesirable or excessive localized strains or stresses may be applied on one or more electronic components, such as on the support areas or mountings of the electronic components. For example, such stresses may result from patient movement, changes in the shape or size of the wound (due to its healing), etc. Such stresses may cause one or more electronic components to move, fall off, or malfunction (e.g., causing an open circuit due to a pin or another connector becoming disconnected). It may be desirable to maintain the position of one or more electronic components, such as one or more sensors, relative to the wound (e.g., in contact with the wound and in the same or substantially the same location or area on the wound contact layer) so that measurements collected by the one or more electronic components accurately capture changes over time in the same or substantially the same location or area of ​​the wound. The surface of a stretchable wound contact layer may move, for example as the patient moves, but it may be desirable to have the one or more electronic components positioned in the same location or area relative to the wound.

[0183] As described herein, in some embodiments, one or more hard, rigid, inelastic, or substantially hard, rigid, inelastic regions, such as one or more regions of inelastic or substantially inelastic material, are attached, positioned, or disposed in a wound contact layer (or another suitable wound dressing component) for supporting one or more electronic components. The mounting, positioning, or placement of one or more electronic components in one or more non-elastic or substantially non-elastic regions may prevent localized stress or stress from forming associated with maintaining the position of the one or more electronic components relative to the wound. In some instances, alternatively or additionally, the one or more electronic components may be flexible, such as mounted on or printed on or supported by one or more flexible materials. For example, flexible plastic sheets or substrates may be used, such as polyimide, polyetheretherketone (PEEK), polyester, silicone, and the like.

[0184] 4A-B illustrate a component 400 having multiple electronic components, according to some embodiments. As shown, a sheet or substrate 430 is configured to support one or more electronic components, including an electronic component or module 402 having multiple connectors and multiple electronic connections 410, as well as non-stretchable or substantially non-stretchable regions. The substrate 430 can be a stretchable or substantially stretchable wound contact layer and can be used with the wound dressing devices described herein.

[0185] The electronics module 402 can be any electronic component described herein, such as a sensor, a light source (such as an LED, a temperature sensor, a light sensor), a controller, or a processor (such as a communications processor).

[0186] The electronic connections 410 may be tracks printed on the substrate 430 using conductive copper, conductive ink (silver ink, graphite ink, etc.), etc. At least some of the electronic connections may be flexible, or stretchable, or substantially flexible or stretchable, and may connect components or modules 402 to the electronic connections 410.

[0187] The connectors can be configured to electronically connect the electronics module 402 to the electronic connections 410 (as illustrated in FIG. 4B), which in turn can connect to other electronics modules (not shown) located on or in other components of the wound dressing, or external to the wound dressing. The connectors can be pins, leads, bumps, etc. Additionally or alternatively, sockets can be used to support and electrically connect the electronics module 402.

[0188] The regions of the substrate or sheet 430 may include a non-elastic or substantially non-elastic material, such as one or more of a suitable adhesive, epoxy, polyester, polyimide, polyamide, PET, PBT, or another type of material having a high Young's modulus. One or more of the regions of non-elastic or substantially non-elastic material may be printed onto the substrate 430. As used herein, printing a material onto a substrate may include one or more of laminating, gluing, or other suitable techniques.

[0189] As described herein, the components of sheet 430 may be positioned in a particular pre-determined configuration. It may be desirable to inspect and verify the positioning of the components of sheet 430. To properly position and verify one or more components, component indexing may be used to automatically locate the position of one or more components on the substrate.

[0190] Component Encapsulation According to some embodiments, one or more coatings or one or more adhesive regions can be applied to one or more components or regions of sheet 430. In some embodiments, the coatings may be applied to the electronic connections 410 or electronics module 402, or other components or regions of sheet 430. It can be a conformal coating configured to seal or coat one or more of the sheets 430 or components supported by the substrate. The coating can provide biocompatibility, insulate or protect the electronic components from contact with fluids, etc. The coating can be one or more of a suitable polymer, an adhesive such as 1072-M UV, light, or heat curable or hardening adhesive, Optimax adhesive (such as NovaChem Optimax8002-LV), Parylene (such as Parylene C), silicone, epoxy, urethane, acrylated urethane, silicone, or another suitable biocompatible and stretchable material.

[0191] In some embodiments, the coating can be thin, such as about 100 microns thick, less than about 100 microns thick, or more than about 100 microns thick. The coating can be applied and cured using one or more of UV, light, or thermal curing. In some implementations, the coating can be applied to the other side of the substrate 430 (or the side facing away from the wound), especially if the substrate is fluid impermeable.

[0192] In some embodiments, one or more adhesive pads, tracks, or areas can be applied to the wound-facing side of substrate 430. In some embodiments, one or more adhesive areas can be patterned to position or secure particular components in particular areas, regions, or locations in contact with or relative to the wound, even while substrate 430 is under stress or pressure.

[0193] In some embodiments, the pattern of adhesive regions can be based on positioning one or more electronic components and can be determined using indexing as described herein. In some embodiments, it can be desirable to pattern the adhesive to provide uniform stress or load on the wound contact layer.

[0194] The adhesive can be patterned to strengthen or support certain areas or regions, such as areas where one or more electronic components are located, while weakening (or making less stiff) other areas to distribute stress or avoid distorting one or more electrical components. For example, it may be desirable to cover at least 50% or more of the wound-facing surface of the wound contact layer with adhesive. In certain implementations, the adhesive may be applied to cover or substantially cover the entire wound-facing side of the wound contact layer.

[0195] The coating can be applied to the sheet 403 or to electronic components positioned on the sheet 403. In some embodiments, the coating can be a biocompatible coating. In some embodiments, the sheet 403 can be a wound contact layer that includes a thin, flexible substrate that conforms to the wound. For example, the substrate or sheet can be made from a stretchable or substantially stretchable material or film, such as polyurethane, TPU, silicone, polycarbonate, polyethylene, polyimide, polyamide, polyester, PET, PBT, PEN, PEI, along with various FEPs and copolymers, or another suitable material. The substrate may not be biocompatible. The coating can be flexible. The coating can include one or more suitable polymers, adhesives such as 1072-M adhesive (e.g., Dymax 1072-M), 1165-M adhesive (e.g., NovaChem Optimax 8002-LV, Dymax 1165-M, etc.), 10901-M adhesive (e.g., Dymax 1901-M or 9001E Dymax), parylene (e.g., Parylene C), silicone, epoxy, urethane, acrylated urethane, acrylated urethane replacement (e.g., Henkel Loctite 3381), or other suitable biocompatible substantially elastic materials. The coating can be a thin coating, for example, from about 80 microns or less, up to several millimeters or more. As described herein, the coating can be applied by one or more of lamination, gluing, welding (e.g., ultrasonic welding), curing with light, UV, heat, etc. The coating can be transparent or substantially transparent to allow for optical detection. The coating can retain bond strength when subjected to sterilization, for example, EtO sterilization. The coating can have a hardness of about A100, A80, A50 or less. The coating can have an elongation at break of about 100%, 200%, 300% or more. The coating can have a viscosity of about 8,000 to 14,500 centipoise (cP). In some cases, the coating can have a viscosity of about 3,000 cP or more.In some cases, the coating can have a viscosity of less than about 3,000 cP. The coating can be fluorescent.

[0196] The coating can be a thin coating, for example, from about 80 microns or less up to several millimeters or more. As described herein, the coating can be cured by one or more of light, UV, heat, etc.

[0197] Coating a thin, flexible substrate with a biocompatible material is not straightforward, as the substrate may need to be coated on the side where the electronic components are located as well as on the opposite side, and the substrate may need to be coated uniformly and comprehensively (e.g., the substrate may be encapsulated with a biocompatible coating).

[0198] The coating can be applied by equipment capable of spraying the coating material on both sides of the substrate or sheet 430. The coating can be applied evenly to one or both sides of the substrate or sheet, and to seal the sides.

[0199] In some embodiments, acrylated urethanes can be used as coating materials because these polymers have suitable adhesive and extensibility properties.

[0200] In some embodiments, it may be desirable for the substrate and electronic components supported by the substrate to be conformable, since the substrate and electronic components are intended to be positioned on or within a body. One property of conformality is the extensibility of the coating material, since it may be necessary to isolate the electronic components from the wound. The coating applied to the substrate may need to have the ability to stretch with the substrate. Combining the elongation properties of both the substrate and the coating can maximize the desired properties of the device. Some examples may be formed from TPU films. The coating may be formed from one or more suitable polymers, adhesives such as 1072-M adhesive (e.g., Dymax 1072-M), 1165-M adhesive (e.g., NovaChem Optimax 8002-LV, Dymax 1165-M, etc.), 10901-M adhesive (e.g., Dymax 1901-M or 9001E Dymax), parylene (e.g., Parylene C), silicone, epoxy, urethane, acrylated urethane, acrylated urethane replacements (e.g., Henkel Loctite 3381), or other suitable materials.

[0201] In some embodiments, the substrate (e.g., TPU) may be hydrophilic and therefore may need to be sealed with a hydrophobic coating to create a hydrophobic dressing that is placed on or in the wound.

[0202] In some embodiments, the coating can be substantially elastic or compliant. In some embodiments, certain areas or different sides of the sheet 430 can have the same or different coatings. In some embodiments, a non-elastic or substantially non-elastic coating can be applied to at least some of the electronic components of the sheet 430. In some embodiments, a non-elastic or substantially non-elastic coating can be applied to the connection tracks 410. Alternatively or in addition to coating the tracks 410, the electronics module 402 can also be coated with a non-elastic or substantially non-elastic coating. The non-elastic or substantially non-elastic coatings described herein can be formed from acrylated or modified urethane materials (Henkel Loctite 3211). For example, the coating can be one or more of Dymax 1901-M, Dymax 9001-E, Dymax 20351, Dymax 20558, Henkel Loctite 3211, or another suitable material. The coating can have a viscosity of about 13,500 cP to 50,000 cP before drying, or about 3,600 cP to about 6,600 cP before drying. In some cases, the coating can have a viscosity of about 50,000 cP or less. The coating can have a hardness of about D40 to about D65, and / or a linear shrinkage of about 1.5 to 2.5%. The coating can be transparent or substantially transparent to allow for optical detection. The coating can be colorless or substantially colorless. The coating 640A can be fluorescent. The coating can retain bond strength when subjected to sterilization, e.g., EtO sterilization.

[0203] In some embodiments, a single layer or multiple layers of adhesive may be applied. In some embodiments, a single layer of a stretchable or non-stretchable coating may be applied. In some embodiments, multiple layers of a stretchable or non-stretchable coating may be applied. For example, multiple layers of coatings may be applied to achieve a desired stiffness or rigidity.

[0204] Embodiments of coatings and components for sensor-enabled sheets or substrates for use in the wound dressings, wound dressing components, wound treatment devices, and methods described herein may also be used in combination with, or in addition to, those described in International Patent Application No. PCT / EP2018 / 059333, filed April 11, 2018, entitled "COMPONENT STRESS RELIEF FOR SENSOR ENABLED NEGATIVE PRESSURE WOUND THERAPY DRESSINGS," and International Patent Application No. PCT / EP2018 / 069883, filed July 23, 2018, entitled "BIOCOMPATIBLE ENCAPSULATION AND COMPONENT STRESS RELIEF FOR SENSOR ENABLED NEGATIVE PRESSURE WOUND THERAPY DRESSINGS," the disclosures of which are incorporated herein by reference in their entireties.

[0205] As described herein, the arrangement of components and adhesives applied to sheet 430 may be applied in a particular predetermined configuration. In addition, the coatings of sheet 430 and components of sheet 430 may be required to fully encapsulate or partially encapsulate the components and / or sheet. Coatings may also be required to be applied uniformly or in various patterns, depending on the type of coating or adhesive and the desired material properties. Thus, it may be desirable to inspect and verify the application and coverage of adhesives or coatings of sheet 430 and components of sheet 430, as well as inspect and verify proper placement of components of sheet 430.

[0206] Inspection of encapsulated electronic components Coated electronic components, including flexible circuit boards, including but not limited to those described herein with respect to wound dressings and wound therapy systems, are inspected for proper manufacture and coating of components. In some embodiments, the circuit board may be stretchable. In some embodiments, flexible and / or stretchable circuit boards may be used similar to the use of flexible circuit boards described herein. The coating material and / or adhesive may be transparent, making it difficult to identify defects or insufficient coverage of the coating or adhesive. Additionally, it may be useful to inspect and verify the placement of components on the flexible circuit board.

[0207] Embodiments of the present application include methods of manufacturing coatings and / or electronic components, as well as inspection methods and apparatus that facilitate verifying their presence and / or location. Although the embodiments are described with respect to electronic components on medical devices, such as wound dressings, it will be understood that the methods and apparatus may also be applicable to non-medical devices.

[0208] In some embodiments, the electronic components and / or flexible circuit boards may utilize adhesives and / or coatings that fluoresce when exposed to ultraviolet (UV) light. In some embodiments, the coating or adhesive may have fluorophores added to the coating or adhesive material. In some embodiments, the coating or adhesive may fluoresce when excited by UV and / or visible light. The fluorescent emitting material may allow for inspection of the electronic components by verifying total coverage of the coating or adhesive or by detecting defects in the coating or adhesive. Additionally, in some embodiments, the use of a coating or adhesive of a fluorescent emitting material may also allow for inspection to verify placement of components on the flexible circuit board. For example, the use of an optically transparent fluorescent emitting material may allow for confirmation of component placement and track integrity after coating. The fluorescent emitting material may allow for inspection of the sufficiency or defects of the coating or adhesive applied to the flexible and / or compliant circuit board. Additionally or alternatively, visual inspection through the visibly transparent coating of the underlying electronic connections or tracks and electronic components after coating may be used to ensure there is no misalignment.

[0209] As used herein, printing a material onto a printed circuit board, sheet, or substrate may include one or more of lamination, adhesion, or any other suitable technique. In some embodiments, an adhesive or coating may be applied to any flexible printed circuit board and / or components on a flexible printed circuit board. In some embodiments, the flexible circuit board may be similar to the sensor array sheet 430 described herein, which is flexible and stretchable.

[0210] In some embodiments, the coating and / or adhesive applied to the PCB can be formed from a material that fluoresces when exposed to UV light, also referred to herein as a UV-initiated fluorescing material. In U.S. Provisional Application No. 62 / 556,479, from which this application claims priority, a material having a UV initiator or a UV-initiated material was defined as any material that reacts and / or fluoresces when exposed to UV light, including UV-initiated fluorescing materials, as well as materials that react but do not necessarily fluoresce when exposed to UV light, such as materials that cure when exposed to UV light. In some embodiments, the UV-initiated fluorescing material can be cured under UV light or cured by one or more of light, UV, heat, etc., as described herein. In some embodiments, the coating and / or adhesive applied to the PCB may be 1072-M adhesive (e.g., Dymax 1072-M), 1165-M adhesive (e.g., NovaChem Optimax 8002-LV, Dymax 1165-M, etc.), 10901-M adhesive (e.g., Dymax 1901-M, or 9001E Dymax), parylene (e.g., Parylene C), silicone, epoxy, urethane, acrylated urethane, acrylated urethane replacement (e.g., Henkel Loctite 3381), other suitable biocompatible and substantially stretchable materials, or another suitable material described herein. The coating and / or adhesive applied to the PCB can be an adhesive, a biocompatible coating, or a non-stretchable or substantially non-stretchable coating, or any other coating described herein, to provide stress relief for the electronic components. Additional embodiments of coatings that can be used with the devices and methods described herein can be found in International Patent Application Nos. PCT / EP2018 / 059333 and PCT / EP2018 / 069883, the disclosures of which are incorporated herein by reference in their entireties.

[0211] 5A-5B illustrate an embodiment of a printed circuit board (PCB) 500 in which electronic components are coated with one or more suitable polymers, adhesives such as 1072-M adhesive (e.g., Dymax 1072-M), 1165-M adhesive (e.g., NovaChem Optimax 8002-LV, Dymax 1165-M, etc.), 10901-M adhesive (e.g., Dymax 1901-M or 9001E Dymax), parylene (e.g., Parylene C), silicone, epoxy, urethane, acrylated urethane, acrylated urethane replacement (e.g., Henkel Loctite 3381), or other suitable materials. As illustrated in FIG. 5A, the coating may be transparent, making it difficult to inspect where the coating has been placed. In some embodiments, the flexible PCB may be coated with a UV-initiated material. In some embodiments, the UV-initiated material may include acrylated polyurethane, other materials described herein, or other materials that fluoresce when exposed to UV light. The coated electronic components and printed circuit board can be subjected to UV exposure, and the fluorescence of the coating or adhesive material can identify the location of the coating or adhesive placed on the sample. FIG. 5B illustrates the coated electronics of FIG. 5A fluorescing as a blue light visible under UV light to identify areas covered with the coating or adhesive. In FIG. 5B, the underlying electronic components covered by the coating are visible under UV light due to the blue fluorescence. In some embodiments, the underlying components are visible when the polymer fluoresces. In some embodiments, the electronic components covered by the coating can be partially obscured, but the outline of the components can be visible as illustrated in FIG. 5B.

[0212] 6A-6D illustrate a flexible sensor array printed circuit having a coating or adhesive of a UV-initiated fluorescent emitting material that is optically transparent and fluoresces under UV light that can allow for full coverage detection and proper placement on the sensor. FIG. 6A-6D illustrates a flexible sensor array printed circuit or sheet similar to the flexible sensor array printed circuit or flexible sensor sheet described with reference to FIG. 4A-4B. The flexible sensor sheet can be coated with a UV-initiated fluorescent emitting material that allows the coating or adhesive material to be visible under UV light. The UV-initiated fluorescent emitting material can fluoresce colors in the visible spectrum (e.g., as visible blue light). The bright spots shown in FIG. 6A-6B are caused on the coating by localized light beams.

[0213] In some embodiments, the UV initiated fluorescent material can include acrylated polyurethane or other materials that fluoresce when exposed to UV light. Figures 6A-6D illustrate a flexible PCB or sheet 630 configured to support one or more electronic components including an electronic component or module 602 having multiple connectors and multiple electronic connections 610. As illustrated in Figures 6A-6D, portions or areas of the flexible PCB or sheet 630 incorporating the electronic components 602 and electronic connections 610 are shown as darker areas and are visible due to the fluorescence of a coating or adhesive material that emits visible light (as illustrated, visible blue light). This visible light is visible due to the fluorescence of the coating or adhesive material. The electronic components and electronic connections can be illuminated through the adhesive material. In some embodiments, the electronic components and electronic connections can be made of a reflective material, and the visible light emitted by the fluorescence of the coating can be reflected from the reflective material. In some embodiments, the electronic components and electronic connections do not need to be made of a reflective material to be visible, since the visible light emitted by the fluorescence of the coating can make the electronic components and electronic connections visible. In some embodiments, this can allow inspection of the placement and arrangement of the electronic components and connections on the flexible PCB, while also allowing inspection of the coating or adhesive material.

[0214] In some embodiments, the coating of the flexible PCB or sheet, the electronic components 602, and the electronic connections 610 may be visible using UV light, visible light, and / or other wavelengths of light. In some embodiments, the transparency or translucency of the coating may allow for inspection of the components 602 and connections 610 using light wavelengths that include light wavelengths but do not include UV excitation wavelengths. In some embodiments, the electronic components or connections may be visible through the coating material under UV light. The components 602 and connections 610 may be visible under visible light. In some embodiments, the coating of the flexible PCB or sheet, the electronic components 602, and the electronic connections 610 may be visible using a combination of wavelengths of both UV excitation wavelengths and visible wavelengths that allow for simultaneous inspection of the electronic components 602, connections 610, and coating integrity. In some embodiments, the flexible PCB or sheet may be inspected only under UV excitation, only under visible light, or under a combination of both to allow for visualization of one or more of the electronic components 602, connections 610, and coating integrity.

[0215] In some embodiments, even if only UV light is used, the emitted or fluoresced light can be visible blue light. This can allow visualization of the coating as it fluoresces, as well as visualization of the electronic components and connections, by illumination with the emitted visible light. For example, even if no visible light is used, if the fluorescence is in visible blue wavelengths, it can allow viewing of the electronic components 602 or connections 610 as if it were illuminated by only blue light. In some embodiments, adding different fluorescent molecules can allow the fluorescent wavelengths emitted by the coating to be selected. For example, the coating can fluoresce green or red.

[0216] In some embodiments, inspection of the electronic components 602 and electronic connections 610 may be possible by transmission of light through the entire assembly, with a light sensor on the opposite side of the flexible PCB or sheet from the light source. In some embodiments, UV light may be transmitted from the light source on the same side of the flexible PCB or sheet as the light sensor.

[0217] In some embodiments, the flexible sensor array printed circuit board can have components positioned at predefined locations. In some embodiments, the fluorescence or color of certain areas of the coated PCB or sheet when exposed to UV light can allow for inspection of the proper configuration or placement of the components of the PCB or sheet. In some embodiments, different components or areas can have coatings applied differently. For example, a pattern of adhesive areas can be used to even out the stress or load on the sheet, as described herein with reference to Figures 4A-4B. In some embodiments, different coatings on different components or areas can appear with different fluorescent intensities or different colors when exposed to UV light, different wavelengths of UV light, or different wavelengths of UV and / or visible light. In some embodiments, the adhesives or coatings described herein, including the first and second coatings described with reference to Figures 9A-9C, are made of a material that fluoresces under UV and / or visible light. For example, if the inspection is intended to be visual or is performed by eye, the excitation will be such that the Stokes shift produces radiation in the visible wavelength range (typically 390-700 nm). Alternatively or additionally, the inspection can be performed using instrumentation. This allows for the use of a wide range of wavelengths. The wavelengths used to excite the material to fluoresce can be different wavelengths of UV, visible light, and / or any other wavelengths that can excite the coating or adhesive material to fluoresce. In some embodiments, the grid or baseline color of the expected locations can be correlated with the color or fluorescent response of the PCB or sheet when exposed to UV or other light. There can be expected colors and / or intensities for molded tracks or electronic components on the PCB or sheet. There can be expected incandescent or colorimetric responses for each component or area of ​​the PCB or sheet that can enable detection of defects in the placement of the components and the application of coatings and adhesives. For example, if a coating, component, or track was in the wrong place, the user would visualize a different color or fluorescent intensity at that location than expected, which could indicate a defect in the coating or component configuration.

[0218] In some embodiments, the inspection of the flexible PCB or sheet can be done by image-based inspection of the PCB or sheet. In some embodiments, the image can be captured, stored, and displayed or viewed to inspect the coating and / or electronic components and connections. In some embodiments, the image of the flexible printed circuit board or sheet under UV and / or visible light can be captured by a camera or light sensor. The image can be displayed on a display, for example, a computer screen, a mobile device screen, or other device for displaying images. In some embodiments, the image of the flexible printed circuit board under UV and / or visible light can be displayed on a display. In some embodiments, the image on the display can show the location of the coating material. In some embodiments, the image on the display can show the location of the electronic components or connections under the coating material. In some embodiments, a UV filter can be used while the flexible PCB or sheet is under the UV lamp. The UV filter can be tinted to block UV damage to the eyes. In some embodiments, a single image can be used to view both the coating and the electronic components and connections. In other embodiments, different types of light can be used to take different images.

[0219] The flexible PCB or sheet can be imaged only under UV excitation, only under visible light, or only under a combination of both to allow visualization of the integrity of one or more of the electronic components 602, connections 610, and coating integrity. In some embodiments, the coating, electronic components 602, and electronic connections 610 of the flexible PCB or sheet 630 may be visible using a combination of both UV excitation and visible wavelengths that allows the electronic components 602, connections 610, and coating integrity to be inspected in a single image. In other embodiments, images of the flexible PCB can be taken under each type of light. In some embodiments, the use of UV or visible light can be adjusted depending on which characteristics of the flexible PCB or sheet are to be inspected.

[0220] Additionally, in some embodiments, specific wavelengths of light can be imaged for the inspection process. For example, a single blue wavelength can be imaged for inspection using the fluorescence of a coating, or a single red wavelength can be imaged for inspection of components or connections. In some embodiments, the visible component of light can be used simultaneously with, or before / after, the UV component of light to image electronic components and electronic connections. In some embodiments, different coating materials applied to the sheet may fluoresce different colors when exposed to UV light.

[0221] In some embodiments, a grid or baseline color of expected coating, component, and connection locations may be correlated with the color or fluorescent response of the PCB or sheet when exposed to UV or other light. There may be an expected incandescent or colorimetric response for each component or area of ​​the PCB or sheet that can be correlated or compared with the actual image captured or displayed on a display to allow detection of defects in component placement and coating and adhesive application.

[0222] In certain circumstances, it may be important to ensure proper coatings and amounts of coatings and adhesives used on the PCB or sheet and components of the PCB or sheet. If the adhesive or coating is applied too thick, it may increase noise or otherwise impede data collection. However, if the adhesive or coating is applied too thin, it may not be able to protect or shield the electronic components. In some embodiments, the intensity of the fluorescence or color may allow detection of the presence of the coating or adhesive as well as visualization of the amount of adhesive or coating. In some embodiments, the intensity of the fluorescence or color may indicate that the type of coating applied is correct. Different types and amounts of adhesives or coatings on the PCB or sheet may have different fluorescence intensities or colors. For example, too much fluorescence response may indicate that too much coating or adhesive was applied to the PCB or sheet. In some embodiments, the intensity of the fluorescence or color may indicate that insufficient coating is present. FIGS. 6C-6D show the fluorescence of a coating with electronic components 602 and electronic connections 610 running up and down the sheet 630. The undulations in the coating are indicated by darker lines or gaps in fluorescence running from left to right on sheet 630 in Figures 6C-6D.

[0223] 7A and 7B illustrate a flexible sheet similar to the flexible sensor array printed circuit described with reference to FIGS. 4A-4B. The flexible sensor sheet can be coated with a material that fluoresces under UV light. The fluorescence of the UV-initiated material coating or adhesive can indicate where the coating or adhesive has been applied. FIGS. 7A and 7B illustrate a flexible sheet having a UV-initiated material coating or adhesive under UV light that can allow detection of the total coverage of the coating or adhesive. As illustrated in FIG. 7A, the UV-initiated material coating or adhesive shows that there is no total coverage of the sheet, indicated by gaps in the fluorescence of the material layer. FIG. 7B illustrates a flexible sheet having a UV-initiated material coating or adhesive, indicated by the total fluorescence of the material layer.

[0224] In some embodiments, the sheet can be coated with a substantially stretchable or extensible coating. In some embodiments, the sheet can be coated with or sealed into a substantially stretchable or extensible coating. Identification of defects in a substantially stretchable or extensible coating or adhesive sealing layer can be accomplished using a substantially stretchable or extensible coating or adhesive material made from or including a material that can fluoresce when exposed to UV light. FIGS. 8A-8D illustrate a flexible sheet 830 having electronic components 802 and electronic connections 810 thereon. The sheet 830 can have perforations 812 in areas of the sheet 830 that are not covered by the electronic components 802 and electronic connections 810. FIG. 8A illustrates an embodiment of a sheet 830 having electronic connections 810 running along the sheet connection components 802 of the sheet 830. The perforations 812 can allow for the transmission of fluid through the sheet 830. The perforations can be located in areas of the sheet 830 that are not covered by the electronic connections 810 and the electronic components 802 .

[0225] FIG. 8A illustrates a sheet 830 with a backing layer 831 covering the wound-facing side of the sheet 830. The backing layer 831 can be used to protect the sheet 830 and / or aid in application of the sheet 830 to a skin surface or wound. The backing layer can be a temporary release liner on one or both ends of the sheet to provide mechanical rigidity and prevent stretching and draping during processing, e.g., coating or sealing the side of the sheet with the electronic components and the tracks on the sheet. The backing layer can aid in handling up to the point of application to the wound. Thus, the backing layer can have tabs, service handles, folds, can be cut into strips, overlapped, and can have numbers, marks, location identification, labels, prohibitions and warnings, or other instructions to aid in application compliance and disposal. If the backing layer is used for processing and sealing the electronic component side, the backing layer can be discarded and a new (or the same) release handle can be placed on the side of the sheet with the coated electronic components. In other embodiments, the backing layer can be left in place, resulting in the coated sheet being sandwiched between the release handles.

[0226] FIG. 8B illustrates the sheet 830 with the backing layer removed. FIGS. 8C and 8D illustrate the sheet 830 coated with an adhesive or coating 814 that fluoresces under UV light. In some embodiments, the coating that fluoresces under UV light can be a substantially stretchable or extensible coating or adhesive that encapsulates the sheet 830 as shown in FIGS. 8C and 8D. As illustrated in FIGS. 8A-8D, the substantially stretchable or extensible coating or adhesive does not cover the perforations 812 in the sheet 830. In some embodiments, the coating or adhesive is applied to an unperforated sheet. The sheet can then be perforated through the coated sheet. The perforations can be formed through one or more suitable methods, such as a laser drilling process, cold pin drilling, hot pin drilling, die cutting, and / or stamping.

[0227] As described above, in some embodiments, certain areas or different sides of the sheet can have the same or different coatings. In some embodiments, additionally or alternatively, a non-stretchable or substantially non-stretchable coating can be applied to at least some of the multiple electronic components of the sheet. FIGS. 9A-9C illustrate a sheet 930 having a connection track 910 and an electronics module 902. FIG. 9C is an enlarged view of a portion of the sheet 930 shown in FIG. 9B. The sheet 930 can include a first coating 914 that is a substantially stretchable or extensible coating or adhesive, and a second coating 915 that is a non-stretchable or substantially non-stretchable coating or adhesive. As illustrated in FIGS. 9A-9C, the non-stretchable or substantially non-stretchable coating 914 can be applied to the electronics module 902. Alternatively or additionally to coating the electronics module 902, the connection track 910 can also be coated with a non-stretchable or substantially non-stretchable coating. In some embodiments, the first coating 914 can be applied before or after the second coating 915. For example, the second coating 915 can be sheet applied first, and the first coating 914 can be applied a second time to cover the second coating 915. In other embodiments, the first coating 914 can be applied first, and then the second coating 915 can be applied.

[0228] In some embodiments, the first coating 914 and / or the second coating 915 can be a material that fluoresces under UV light or can be a material that includes moieties that fluoresce. In some embodiments, the first coating 914 can fluoresce a different color than the second coating 915. The pair of colors can be selected to be easily distinguishable by eye, and the polymers can be selected so that the first coating 914 does not substantially absorb the light emitted by the second coating 915. For example, if the second coating 915 emits blue and the first coating 914 absorbs blue and emits red, this can create problems. The coatings can be optically clear to allow visual inspection of the components. As illustrated in FIGS. 9A-9C, the first coating 914 can be a substantially stretchable or extensible coating or adhesive that can fluoresce a first color (e.g., blue) when exposed to UV light, and the second coating 915 can be a non-stretchable or substantially non-stretchable coating that can fluoresce a second color (e.g., red) when exposed to UV light. In FIG. 9A, the two colors are highlighted by different hash marks in certain areas. In other embodiments, the first coating 914 can fluoresce the same color as the second coating 915. In some embodiments, the first coating 914 can fluoresce the same color as the second coating 915, but at different intensities to distinguish between the two coatings of the same color.

[0229] 9B and 9C show images of a sheet 930 having a first coating 914 and a second coating 915 under UV light. The first coating 914 is shown as a material covering substantially the entire surface of the sheet 930. The second coating 915 is shown as a material that fluoresces a different color and is shown in FIG. 9C as a lighter colored material as small areas or dots throughout the sheet 930. FIG. 9C illustrates a sheet 930 having two coatings. The sheet 930 can include a first coating 914 that is a substantially stretchable or extensible coating or adhesive, and a second coating 915 that is a non-stretchable or substantially non-stretchable coating or adhesive. The fluorescent emission of the coatings can be used to visualize defects or areas of the sheet 930 that have incomplete coating. For example, FIG. 9C illustrates an electronics module 917 that was not coated or was not fully covered with the second coating 915, as illustrated by the lack of fluorescent emission from the second coating 915 in that area of ​​the sheet 930.

[0230] 9A-9C illustrate the inspection of sheet 930 by UV fluorescence. As illustrated in FIGS. 9A-9C, a first coating 914 can fluoresce a first color (e.g., blue) when exposed to UV light, and a second coating 915 can fluoresce a second color (e.g., red) when exposed to UV light. This can allow for a clear distinction between the two materials during visual inspection. This can also allow for errors in the coating to be easily visible, as illustrated in FIG. 9C.

[0231] In some embodiments, the coating or adhesive material may include fluorophores of various emission wavelengths. In some embodiments, the fluorophores may be added to any of the coatings or adhesives described herein. Each coating or adhesive may have a fluorophore of a different wavelength. This may allow for visual evaluation of the different coatings. In some embodiments, only one of the coatings or adhesives may have a fluorophore. For example, the first coating 914 may not have any emission or any fluorescence when exposed to UV light, and the second coating 915 may include a fluorophore and may emit a color when exposed to UV light. In some embodiments, the fluorophore may be dispersed in the polymer coating or adhesive in the form of beads, granules, or other topically contained media (e.g., fluorescent microparticles, microbeads, or quantum dots). When using the sheet as a medical or wound care device, the fluorophore may be biocompatible. Alternatively or additionally, the fluorophore may be encapsulated within a biocompatible coating. In some embodiments, the fluorophores in the coating or adhesive may be non-leachable / non-extractable from the coating or adhesive in physiological fluids or suitable test fluids, such as polar and non-polar extraction media, or those listed in, for example, ISO 10993. In some embodiments, the substance is not on the UK Medicines and Healthcare Products Regulatory Agency (MHRA) list.

[0232] The first coating 914 and the second coating 915 can have different emission wavelengths. For example, the first coating 914, which is a substantially stretchable or extensible coating or adhesive, can emit blue visible light, and the second coating 915, which is a non-stretchable or substantially non-stretchable coating or adhesive, can emit red visible light. Other combinations can also be used that do not include any fluorescent emission from one of the coatings. In some embodiments, the fluorescent emission emission wavelength of the second coating can be the same as that of the first coating. In some embodiments, the radiant intensity of the second coating can be matched to the radiant intensity of the first coat.

[0233] Identification of voids in a coating or adhesive can be accomplished using the fluorescent properties of a substantially stretchable or extensible coating or adhesive and / or a non-stretchable or substantially non-stretchable coating or adhesive. In some embodiments, providing a coating or adhesive material that can fluoresce under UV light can allow visualization of voids in the coating by identifying areas of the sheet that are not present with any fluorescent emission radiation. When identifying gas bubbles, in a substantially stretchable or extensible coating or adhesive (where gas bubbles are not present above or below an opaque electronics module or track), light transmission is more effective in detecting gas bubbles in the substantially stretchable or extensible coating or adhesive coating. In some embodiments, identification of gas bubbles in a non-stretchable or substantially non-stretchable coating or adhesive can also utilize light transmission to detect gas bubbles in the coating. For example, gas bubbles can be visualized and identified by observing or measuring the transmission of light or color or intensity of the coating. When gas bubbles are present, the color or intensity of the coating is different from the color or intensity of the coating in areas of the sheet where no gas bubbles are present. In some embodiments, the same techniques described herein can be used to detect foreign bodies in substantially elastic or compliant coatings or adhesives, and / or non-elastic or substantially non-elastic coatings or adhesives. In some embodiments, foreign bodies can also be identified by light transmission, reflection, and / or direct imaging (i.e., photography).

[0234] If voids or gas bubbles are present under the components, they can cause failure of the components. To identify voids or gas bubbles under the components when the sheet is transparent, optical visibility can be obtained from under the components on the side of the sheet opposite the components on the sheet. The voids or gas bubbles can be optically seen through the transparent sheet.

[0235] As discussed above, the coating or adhesive can be applied by a robotic spray head that moves in the x / y axis in a serpentine pattern while spraying the coating or adhesive on the substrate. A straight serpentine pattern leads to uneven topographical coverage in the form of peaks and valleys in the same direction as the serpentine. This is known as the "plow field effect." This can lead to inconsistent readings on the impedance pad, but this effect can be minimized by proper spray settings or parameters in the controller that controls the robotic spray. Other patterns of coating can be used. For example, tracing the perimeter of a square sheet and indexing, where one axis runs inward or repeatedly parallel, can be used. Because the sheet can be transparent, it can be difficult to visually assess the unevenness of the coating on the surface of the sheet once it is coated. It can be useful to provide a method of inspection to ensure that both the process is quantified to devise a spray pattern that minimizes unevenness, as well as a means of inspection during production to ensure that the desired output is maintained.

[0236] In some embodiments, the substantially stretchable or extensible coating or adhesive described herein can be used to coat and / or seal the sheet and can fluoresce under UV light. The fluorescent properties of the substantially stretchable or extensible coating or adhesive under UV light as described herein can make the inspection process of the sheet easier. In some embodiments, to visually evaluate the coating on the sheet, the sheet can be placed on an orange substrate. In some embodiments, the orange substrate is a piece of orange paper. The coating or adhesive can be exposed to UV light, and the coating or adhesive can fluoresce when exposed to UV light. This visual evaluation technique, utilizing the fluorescent properties of the coating or adhesive or of a fluorescent material incorporated into the coating or adhesive, can make it extremely easy to visually evaluate the peaks and valleys that result from the spraying or application process. FIGS. 10A-10C illustrate an experimental set-up of a sheet or other material coated with one or more coatings or adhesives described herein. The sheets in FIGS. 10A-10C are transparent. FIG. 10A illustrates an embodiment of a sheet or other material encapsulated in a coating or adhesive described herein that is also transparent. FIG. 10A illustrates an embodiment of a transparent sheet encapsulated in a transparent coating or adhesive against a colorless background without fluorescence. FIG. 10B illustrates an embodiment of a sheet or other material encapsulated in a coating or adhesive against a colored background (e.g., an orange background) without fluorescence. FIG. 10C illustrates an embodiment of a sheet or other material encapsulated in a coating or adhesive against a colored background (e.g., an orange background) with fluorescence. The colored background can be used to quantify the non-uniformity. As illustrated in FIGS. 10A-10C, the colored background with fluorescence allows for a stronger contrast during visualization of the coating non-uniformity. The colored background can be applied by using a colored material on the back of the sheet.In other embodiments, a visualization system can be used in conjunction with software that can assess the intensity of color that has penetrated the adhesive and quantify non-uniformity.

[0237] Additionally or alternatively to inspection by fluorescent emission, the coating can be inspected for sufficiency in electrical protection of the components. In some embodiments, testing of the flexible printed circuit board can be done utilizing an electrostatic air discharge plate or probe. In some embodiments, a high voltage plate is placed on the coated flexible PCB or coated sheet with the sheet connector grounded. If the conformal coating is insufficient, an electrostatic discharge (or corona discharge) will short through the coating, identifying the error and in some cases rendering the PCB or sheet unusable. In some embodiments, an image can be captured to detect where the corona discharge is located on the flexible PCB or sheet. If the coating of the flexible PCB or sheet is sufficient and correctly applied, the testing is non-destructive.

[0238] In some embodiments, the coatings, adhesives, and components described herein with reference to the flexible and / or extensible sensor array printed circuits or flexible sheets of Figures 3A-3B, 4A-4B, and 6A-7B can be applied to any flexible circuit board or printed circuit board. For example, the coatings, adhesives, and components described herein with reference to the flexible sensor array printed circuits or flexible sheets of Figures 3A-3B, 4A-4B, and 6A-7B can be applied to a printed circuit board similar to the printed circuit board of Figures 5A-5B. Fluorescence inspection techniques of adhesive, coating, and component arrangements utilizing UV-initiated materials of adhesives or coatings of the flexible sensor array printed circuits or flexible sheets of Figures 3A-3B, 4A-4B, and 6A-7B as described herein can be used to inspect coatings, adhesives, and components of any flexible circuit board or printed circuit board.

[0239] Other Variations Any values ​​of thresholds, limits, periods, etc. provided herein are not intended to be absolute and may therefore be approximate. Furthermore, any thresholds, limits, periods, etc. provided herein may be fixed or varied, either automatically or by a user. Furthermore, as used herein, terms expressing a relative degree, such as exceeding, over, under, etc., in relation to a reference value are intended to encompass equality to the reference value. For example, exceeding a positive reference value may encompass being equal to or greater than the reference value. Moreover, as used herein, terms expressing a relative degree, such as exceeding, over, under, etc., in relation to a reference value are intended to encompass the inverse of the disclosed relationship, such as below, under, over, etc., in relation to the reference value. Also, although various process blocks may be described with respect to determining whether a value reaches or does not reach a particular threshold, the blocks may be similarly interpreted with respect to, for example, whether a value is (i) below or over a threshold, or (ii) meeting or not meeting a threshold.

[0240] It is to be understood that features, materials, properties, or groups described in conjunction with a particular aspect, embodiment, or example are applicable to any other aspect, embodiment, or example described herein, unless incompatible. All of the features disclosed in this specification (including any of the accompanying claims, abstract, and drawings), or all of the steps of any method or process disclosed in the same, may be combined in any combination, except combinations in which at least some of such features or steps are mutually exclusive. Protection of the invention is not limited to the details of any of the foregoing embodiments. Protection extends to any novel, or any novel combination of features disclosed in this specification (including any of the accompanying claims, abstract, and drawings), or to any novel, or any novel combination of steps of any method or process disclosed in the same.

[0241] Although specific embodiments have been described, these embodiments are presented merely as examples and are not intended to limit the scope of protection. Indeed, the novel methods and systems described herein may be embodied in a variety of other forms. Furthermore, various omissions, substitutions, and modifications may be made in the form of the methods and systems described herein. Those skilled in the art will recognize that in some embodiments, the actual steps performed in the illustrated or disclosed processes may differ from the steps shown in the figures. In some embodiments, certain steps of the steps described above may be removed and others may be added. For example, the actual steps or order of steps performed in the disclosed processes may differ from those shown in the figures. In some embodiments, certain steps of the steps described above may be removed and others may be added. For example, the various components shown in the figures may be implemented as software or firmware on a processor, controller, ASIC, FPGA, or dedicated hardware. Hardware components may include logic circuitry, such as controllers, processors, ASICs, FPGAs, and the like. Additionally, the features and characteristics of specific embodiments disclosed above can be combined in various ways to form additional embodiments, all of which will fall within the scope of the present disclosure.

[0242] Conditional language such as "can," "could," "might," or "may," unless specifically stated otherwise or interpreted otherwise within the context in which it is used, is generally intended to convey that certain embodiments include certain features, elements, or steps, while other embodiments do not. As such, such conditional language is not necessarily intended to suggest that features, elements, or steps are in any way required by one or more embodiments, or that one or more embodiments necessarily include logic for determining, with or without user input or instruction, whether those features, elements, or steps are included in or should be performed in any particular embodiment. Terms such as "comprising," "including," and "having" are synonymous and are used in an inclusive, non-limiting manner and do not exclude additional elements, features, acts, operations, and the like. Also, the term "or" is used in an inclusive sense (not an exclusive sense), e.g., when used to join a list of elements, it means one, some, or all of the elements in the list. Further, the term "each" as used herein, in addition to having its ordinary meaning, can also refer to any subset of the list of elements to which the term "each" is applied.

[0243] Conjunctive phrases such as "at least one of X, Y, and Z," unless specifically stated otherwise, are understood differently with the context in which they are generally used to convey that an item, term, etc. can be either X, Y, or Z. Thus, such conjunctive phrases are generally not intended to suggest that a particular embodiment requires that it includes at least one of X, at least one of Y, and at least one of Z.

[0244] As used herein, degree-expressing phrases used herein, such as the terms "approximately," "about," "generally," and "substantially," refer to a value, amount, or characteristic that is close to a given value, amount, or characteristic that still performs a desired function or produces a desired result. For example, the terms "approximately," "about," "generally," and "substantially" can refer to an amount that is within 10%, 5%, 1%, 0.1%, and 0.01% of a given amount. As another example, in certain embodiments, the terms "generally parallel" and "substantially parallel" refer to a value, amount, or characteristic that deviates from exactly parallel by 15 degrees or less, 10 degrees or less, 5 degrees or less, 3 degrees or less, 1 degree or less, or 0.1 degrees or less.

[0245] All of the features disclosed in this specification (including any of the accompanying claims, abstract, and drawings), or all of the steps of any method or process disclosed in the same, may be combined in any combination, except combinations in which at least some of such features or steps are mutually exclusive. The disclosed subject matter is not limited to the details of any of the foregoing embodiments. The disclosure does not include any novel, or any novel combination of, features disclosed in this specification (including any of the accompanying claims, abstract, and drawings), or any of the steps of any method or process disclosed in the same. or any new combination of the above.

[0246] Various modifications to the implementations described in this disclosure may be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other implementations without departing from the spirit or scope of the disclosure. Thus, the disclosure is not intended to be limited to the implementations shown herein, but should be accorded the widest scope consistent with the principles and features described herein. Particular embodiments of the disclosure are covered in the set of claims listed below or presented hereafter. The language of the claims should be interpreted broadly based on the language used in the claims, and not limited to the examples described herein or described during the prosecution of this application, but should be interpreted as non-exclusive. The scope of the disclosure is not intended to be limited by the specific disclosure of the preferred embodiments herein, but can be defined by the claims presented herein or presented hereafter.

[0247] [Additional note 1] 1. A method for testing a flexible printed circuit board, comprising: applying a coating material to the flexible printed circuit board, the coating material including a material that fluoresces when exposed to UV or visible light, the flexible printed circuit board including one or more electronic components; placing the coated flexible printed circuit board under UV or visible light to cause the coating material to fluoresce. [Additional note 2] 2. The method of claim 1, wherein the coating material comprises an adhesive material. [Additional note 3] 3. The method according to any one of claims 1 to 2, wherein the coating material comprises an acrylated polyurethane. [Additional note 4] 4. The method according to any one of claims 1 to 3, further comprising displaying an image of the flexible printed circuit board under UV or visible light on a display. [Additional note 5] 5. The method of claim 4, wherein the image on the display indicates the location of the coating material. [Additional note 6] 6. The method of claim 4 or 5, wherein the image on the display indicates the location of the one or more electronic components and / or one or more electronic connections or tracks beneath the coating material. [Additional note 7] 7. The method according to any one of claims 1 to 6, wherein the UV or visible light is transmitted from a light source on the same side of the flexible printed circuit board as a light sensor. [Additional note 8] 7. The method of any one of claims 1 to 6, wherein the UV or visible light is transmitted from a light source on the flexible printed circuit board opposite a light sensor. [Additional note 9] 9. The method according to any one of claims 1 to 8, further comprising measuring the fluorescence intensity of the coating material while exposed to UV or visible light. [Additional Note 10] 10. The method of any one of claims 1 to 9, wherein the one or more electronic components are visible through the coating material under UV or visible light. [Additional Note 11] 11. The method of any one of claims 1 to 10, further comprising placing the flexible printed circuit board under UV light and under visible light. [Additional Note 12] 12. The method of any one of claims 1 to 11, further comprising displaying images of the flexible circuit board under different wavelengths of visible light and / or UV light. [Additional Note 13] 13. The method of any one of claims 1 to 12, further comprising testing the flexible printed circuit board for corona discharge. [Additional Note 14] 14. The method of claim 13, further comprising taking an image of the location of the corona discharge. [Additional Note 15] 1. A method of manufacturing a flexible sensor sheet for use on a wound, comprising: Providing a flexible substrate; Electronic components, including one or more sensors for detecting wound characteristics, are positioned on the flexible substrate. And applying a coating material onto the flexible substrate and / or the electronic component; and positioning the flexible substrate under UV or visible light to cause the coating material to fluoresce. [Additional Note 16] 16. The method of claim 15, wherein the coating material comprises an adhesive material. [Additional Note 17] 17. The method according to any one of claims 15 to 16, wherein the coating material comprises an acrylated polyurethane. [Additional Note 18] 18. The method according to any one of appended items 15 to 17, further comprising displaying an image of the flexible substrate under UV or visible light on a display. [Additional Note 19] 20. The method of claim 18, wherein the image on the display indicates the location of the coating material. [Additional Note 20] 20. The method of claim 18 or 19, wherein the image on the display indicates the location of the electronic component beneath the coating material. [Additional Note 21] 21. The method according to any one of appended items 15 to 20, wherein the UV or visible light is transmitted from a light source on the same side of the flexible substrate as a light sensor. [Additional Note 22] 21. The method of any one of claims 15 to 20, wherein the UV or visible light is transmitted from a light source on the flexible printed circuit board opposite a light sensor. [Additional Note 23] 23. The method according to any one of appended claims 15 to 22, further comprising measuring the fluorescence intensity of the coating material while exposed to UV or visible light. [Additional note 24] 24. The method according to any one of appended claims 15 to 23, wherein the electronic component is visible through the coating material under UV or visible light. [Additional note 25] 25. The method according to any one of appended claims 15 to 24, wherein the electronic component is visible through the coating material under UV or visible light. [Additional note 26] 26. The method of any one of claims 15 to 25, further comprising positioning the flexible substrate under UV light and under visible light. [Additional note 27] 27. The method of any one of claims 15 to 26, further comprising testing the flexible printed circuit board for corona discharge. [Additional note 28] 28. The method of claim 27, further comprising taking an image of the location of the corona discharge. [Additional note 29] 1. A flexible sensor sheet for use on a wound, comprising: A flexible substrate; an electronic component including one or more sensors positioned on the flexible substrate for detecting wound characteristics; and a material coating the flexible substrate and / or electronic components that fluoresces when exposed to UV or visible light. [Additional note 30] 30. The flexible sensor sheet of claim 29, wherein the material that fluoresces when exposed to UV or visible light includes an adhesive material. [Additional note 31] 31. The flexible sensor sheet according to any one of claims 29 to 30, wherein the material that emits fluorescence when exposed to UV or visible light comprises acrylated polyurethane. [Additional note 32] 32. The flexible sensor sheet of any one of appended claims 29 to 31, wherein a first portion of the flexible substrate is coated with a first material that emits fluorescence when exposed to UV or visible light, and a second portion of the flexible substrate is coated with a second material that emits fluorescence when exposed to UV or visible light, the first material being different from the second material. [Additional note 33] 13. A method for inspecting a flexible printed circuit board or a flexible sensor sheet, comprising testing the flexible printed circuit board for corona discharge. [Additional note 34] 1. A method for testing a flexible printed circuit board, comprising: applying a coating material to the flexible printed circuit board, the coating material comprising a material configured to fluoresce when exposed to UV or visible light, the flexible printed circuit board comprising one or more electronic components; placing the coated flexible printed circuit board under UV or visible light to cause the coating material to fluoresce; measuring the fluorescent emission of the coating material to detect voids or uneven application of the coating material; and measuring the light transmittance of the coating material to detect gas bubbles in the coating material. [Additional note 35] 35. The method of claim 34, wherein the wound-facing surface of the flexible printed circuit board is exposed to UV or visible light. [Additional note 36] 35. The method of claim 34, wherein the surface of the flexible printed circuit board opposite the wound-facing surface is exposed to UV or visible light. [Additional note 37] 35. The method of claim 34, wherein the coating material comprises an adhesive material. [Additional note 38] 38. The method according to any one of claims 34 to 37, wherein the coating material comprises an acrylated polyurethane. [Additional note 39] 39. The method of any one of claims 34 to 38, further comprising displaying an image of the flexible printed circuit board under UV or visible light on a display. [Additional note 40] 40. The method of claim 39, wherein the image on the display indicates the location of the coating material. [Additional note 41] 41. The method of claim 39 or 40, wherein the image on the display indicates the location of the one or more electronic components beneath the coating material. [Additional note 42] 42. The method according to any one of claims 34 to 41, wherein the UV or visible light is transmitted from a light source on the same side of the flexible printed circuit board as a light sensor. [Additional note 43] The UV or visible light is emitted from a light source on the flexible printed circuit board opposite a light sensor. 42. The method according to any one of Addendum 34 to 41, wherein the antibody is permeated. [Additional note 44] 44. The method according to any one of claims 34 to 43, further comprising measuring the fluorescence intensity of the coating material while exposed to UV or visible light. [Additional note 45] 45. The method of any one of claims 34 to 44, wherein the one or more electronic components are visible through the coating material under UV or visible light. [Additional note 46] 46. ​​The method of any one of claims 34 to 45, further comprising positioning the flexible printed circuit board under UV light and under visible light. [Additional note 47] 47. The method of any one of claims 34 to 46, further comprising displaying images of the flexible printed circuit board under different wavelengths of visible light and / or UV light. [Additional note 48] 48. The method of any one of claims 34 to 47, further comprising testing the flexible printed circuit board for corona discharge. [Additional note 49] 49. The method of claim 48, further comprising taking an image of the location of the corona discharge. [Additional Note 50] 1. A method for testing a compliant and flexible printed circuit board, comprising: applying a coating material to the compliant and flexible printed circuit board, the coating material comprising a material that fluoresces when exposed to UV or visible light, the compliant and flexible printed circuit board comprising one or more electronic components; placing the coated compliant and flexible printed circuit board under UV or visible light to cause the coating material to fluoresce. [Additional note 51] A method of manufacturing comprising one or more of the features set forth in the preceding description. [Additional note 52] A method of testing comprising one or more of the features set out in the preceding description. [Additional note 53] A system for inspecting comprising one or more of the features set forth in the preceding description. [Additional note 54] A wound dressing device including one or more of the features set forth in the preceding description. [Additional note 55] A wound dressing component comprising one or more of the features set forth in the preceding description.

Claims

[Claim 1] 1. A method for testing a flexible printed circuit board, comprising: applying a coating material to the flexible printed circuit board, the coating material including a material that fluoresces when exposed to UV or visible light, the flexible printed circuit board including one or more electronic components; and placing the coated flexible printed circuit board under UV or visible light to cause the coating material to fluoresce.

Images