Uv indicator with protective layer

Abstract

The device (5) includes a first layer (20) containing a colorimetric indicator; and a second layer (30) disposed on at least a portion of the first layer (20), the second layer (30) containing or being composed of a protective material, wherein the protective material is transparent or substantially transparent to UV radiation, and wherein the protective material contains or is composed of a glass material or a polymer material.

Description

Technical Field

[0001] This invention relates to an ultraviolet (UV) colorimetric indicator. In particular, but not exclusively, this invention relates to a UV colorimetric indicator that exhibits improved properties, such as reduced variability in reactivity and / or reduced tendency to change with temperature. Background Technology

[0002] Many products exist that provide a visual indication (through color change) of exposure to a certain amount of a specific compound or radiation. Such products typically include one or more colorimetric indicators. For example, colorimetric indicators rely on the optical properties of reactive dyes or inks. These dyes can exist in at least two different chemical states, each form absorbing light within a specific wavelength range. When this reactive dye, existing in its first form, is exposed to a given substance, it reacts with that substance through a reversible chemical reaction, thus becoming a second form of the dye. Because the second form of the dye absorbs light at a different wavelength, the chemical reaction provides a color change visible to the observer. Colorimetric indicators can be configured to display reversible or irreversible color changes, depending on their intended use and the chemical substance, radiation, or stimulus that causes the indicator's color change. Examples of colorimetric indicators reactive to ultraviolet radiation (UVR) are disclosed in WO 2010 / 070290 (Mills et al.), the contents of which are incorporated herein by reference in their entirety.

[0003] Exposing a surface to a given type of radiation may be intentional or unintentional, or it may be deliberate or accidental.

[0004] For example, while exposing human skin to direct sunlight may be desirable and to some extent beneficial, excessive exposure to ultraviolet radiation is a recognized health hazard. Some products exist, such as stickers or wristbands sold under the name Smartsun™, which include colorimetric indicators that show a color change after exposure to a certain type and / or amount of UV radiation. This provides the user with a visual indication of the association between exposure to a predetermined amount of UV radiation.

[0005] In another example related to sterilization and disinfection, the product includes a colorimetric indicator that displays a color change after exposure to a certain amount of UVC radiation. This provides the user with a visual indication of the association with UVC radiation exposure. UVC irradiation is a known technique for disinfecting and sterilizing surfaces, such as in medical settings or the food industry.

[0006] Other products rely on colorimetric indicators that change color when exposed to specific compounds or chemicals, such as carbon dioxide, oxygen, ammonia, etc. These are useful, for example, in the food industry.

[0007] The problem with existing indicators (especially UV indicators) is that the reactivity (reaction rate) of colorimetric indicators (typically in the form of photochromic inks printed on a substrate) depends on temperature. Generally, the higher the temperature, the faster the color change. Therefore, although the intensity of the color change will ultimately depend on the exposure dose, the reaction rate can vary with temperature.

[0008] Various types of indicators may include a covering or other form of UV protection.

[0009] For example, CN1317536A discloses a photochromic layer sandwiched between two glass layers. However, this document does not involve UV indicators, and the purpose of the glass layers is to provide UV protection and glare shielding.

[0010] The JPS60205429A, which does not involve a UV indicator, has a glass layer to prevent damage to the reactive material.

[0011] JPS59136669A relates to photoluminescent (fluorescent) glass materials and protects the reactive glass from pre-dose reactions by means of a MgF2 coating on the glass.

[0012] US2017023681A1 (Patel) relates to radiation-sensitive devices whose surfaces are protected from UV light by a UV reflective layer.

[0013] US3290499A discloses a radiation indicator that prevents visible and ultraviolet light by incorporating an ultraviolet absorber.

[0014] GB1210047A discloses a threshold dosimeter that shields against environmental influences by embedding it in a transparent substrate of water-soluble polyvinyl alcohol.

[0015] US5028792A discloses a membrane for monitoring ionizing radiation dose and provides protection against UV light by incorporating a UV absorber.

[0016] US 2020 / 0149960 A1 (Foller) discloses a wearable indicator covered with a protective layer in the form of a coating film. The coating film can be treated with an oleophobic coating.

[0017] Therefore, none of these studies have addressed the problem of mitigating the temperature dependence of the responsiveness of ultraviolet indicators.

[0018] The purpose of this invention is to solve and / or mitigate one or more problems associated with the prior art. Summary of the Invention

[0019] This invention is based on the discovery that the aforementioned problems can be mitigated (while maintaining the full functionality of the dosimeter) by covering the indicator with a glass or polymer layer. This is surprising because glass is generally considered to absorb at least some types of UV radiation and is not generally considered compatible with UV indicators. Similarly, many types of polymers are considered to absorb at least some types of UV radiation and are not generally considered compatible with UV indicators.

[0020] According to a first aspect, an apparatus is provided, comprising:

[0021] The first layer contains the colorimetric indicator; and

[0022] A second layer disposed on at least a portion of the first layer, the second layer comprising or being composed of a protective material, wherein the protective material is transparent or substantially transparent to UV radiation, and wherein the protective material comprises or is composed of a glass material or a polymer material.

[0023] Preferably, the second layer (e.g., a protective layer) may cover the first layer.

[0024] Preferably, the second layer (e.g., a protective layer) may cover the colorimetric indicator.

[0025] The second layer (e.g., a protective layer) can block less than about 50% (e.g., less than about 40%, less than about 30%, less than about 20%, less than about 10%, less than about 5%, less than about 1%) of UV radiation (e.g., UV-A, UV-B, and / or UV-C radiation).

[0026] Glass Examples

[0027] The protective material may contain glass or may be composed of glass.

[0028] The glass material may comprise glass having a silica content of at least 80 wt%, or may consist of glass having a silica content of at least 80 wt%, where at least 80 wt% is, for example, at least 85 wt%, at least 90 wt%, at least 95 wt%, or at least 99 wt%. Advantageously, using a glass material with a high silica content can impart advantageous optical properties to the glass material, including transparency to UV radiation. Advantageously, the glass material may be transparent or substantially transparent to UV radiation (e.g., to UV-A, UV-B, and / or UV-C radiation). The glass material may block less than about 20% (e.g., less than about 10%, less than about 5%, less than about 1%) of UV radiation (e.g., UV-A, UV-B, and / or UV-C radiation).

[0029] The glass material may contain high silica glass or may be composed of high silica glass.

[0030] Glass materials may include quartz glass (also known as fused silica or fused silicon dioxide) or may be composed of quartz glass.

[0031] Therefore, in one embodiment, an apparatus is provided, comprising:

[0032] The first layer contains the colorimetric indicator; and

[0033] A second layer disposed on at least a portion of the first layer, wherein the second layer covers the colorimetric indicator, and wherein the second layer is made of a glass material that is transparent or substantially transparent to UV radiation.

[0034] The glass material can block less than about 20% (e.g., less than about 10%, less than about 5%, less than about 1%) of UV radiation (e.g., UV-A, UV-B and / or UV-C radiation).

[0035] In another embodiment, an apparatus is provided, comprising:

[0036] The first layer contains the colorimetric indicator; and

[0037] A second layer disposed on at least a portion of the first layer, wherein the second layer covers the colorimetric indicator, and wherein the second layer is made of a glass material, wherein the glass material comprises or is composed of high silica glass.

[0038] The glass material may include quartz glass (also known as fused silica or fused silicon dioxide) or may be composed of quartz glass.

[0039] The glass material may include glass having a silica content of at least 80 wt% or may be composed of glass having a silica content of at least 80 wt%, where at least 80 wt% is, for example, at least 85 wt%, at least 90 wt%, at least 95 wt%, or at least 99 wt%.

[0040] Surprisingly, it was found that providing a UV-transparent glass layer on the indicator reduced or prevented fluctuations in colorimetric changes caused by temperature within the indicator upon exposure. Without being bound by theory, it is believed that the glass layer can block or reflect at least some of the heat associated with UV radiation (e.g., heat generated by the UV source), thereby minimizing temperature fluctuations on or within the indicator upon exposure.

[0041] At least a portion of the second layer (e.g., glass material) can be substantially transparent to visible light. This arrangement ensures that the second layer does not adversely affect the user's or observer's view of the first layer (e.g., an indicator).

[0042] The second layer (e.g., glass material) may have a thickness of about 0.1-1 mm (e.g., about 0.1 to 0.5 mm, about 0.2 to 0.5 mm, or about 0.3 mm).

[0043] Polymer Implementation Plan

[0044] The protective material may contain polymer materials or may be composed of polymer materials.

[0045] The polymer material may comprise polyolefins and / or fluorinated polymers, or may be composed of polyolefins and / or fluorinated polymers.

[0046] The polymer material may contain fluorinated polymers, or may be composed of fluorinated polymers.

[0047] The polymer material may comprise a fluorinated addition homopolymer or copolymer, or may be composed of a fluorinated addition homopolymer or copolymer.

[0048] The polymer material may contain or be composed of tetrafluoroethylene (TFE) homopolymers or copolymers.

[0049] The polymer material may contain fluorinated polyolefins, or may be composed of fluorinated polyolefins.

[0050] The polymer material includes ETFE (ethylene tetrafluoroethylene copolymer) or FEP (fluorinated ethylene propylene), or may be composed of ETFE or FEP.

[0051] The polymer material may comprise or be composed of perfluoroether homopolymers or copolymers.

[0052] The polymer material may comprise, or may be composed of, perfluoroalkoxyalkane (PFA) polymers.

[0053] Advantageously, the polymer material can be transparent or substantially transparent to UV radiation (e.g., to UV-A, UV-B, and / or UV-C radiation). The polymer material can block less than about 50% (e.g., less than about 40%, less than about 30%, less than about 20%, less than about 10%, less than about 5%, less than about 1%) of UV radiation (e.g., UV-A, UV-B, and / or UV-C radiation).

[0054] Therefore, in one embodiment, an apparatus is provided, comprising:

[0055] The first layer contains the colorimetric indicator; and

[0056] A second layer disposed on at least a portion of the first layer, wherein the second layer covers the colorimetric indicator, and wherein the second layer is made of a polymeric material that is transparent or substantially transparent to UV radiation.

[0057] The polymer material can block less than about 50% (e.g., less than about 40%, less than about 30%, less than about 20%, less than about 10%, less than about 5%, less than about 1%) of UV radiation (e.g., UV-A, UV-B and / or UV-C radiation).

[0058] In another embodiment, an apparatus is provided, comprising:

[0059] The first layer contains the colorimetric indicator; and

[0060] A second layer disposed on at least a portion of the first layer, wherein the second layer covers the colorimetric indicator, and wherein the second layer is made of a polymeric material comprising, or consisting of, a fluorinated addition homopolymer or copolymer.

[0061] Surprisingly, it was found that providing a UV-transparent polymer layer on the indicator reduced or prevented fluctuations in colorimetric changes caused by temperature within the indicator upon exposure. Without being bound by theory, it is thought that providing a polymer layer (e.g., ETFE, FEP, or PFA) can block or reflect at least some of the heat associated with UV radiation (e.g., heat generated by a UV source), thereby minimizing temperature fluctuations on or within the indicator upon exposure.

[0062] At least a portion of the second layer (e.g., a polymer material) may be substantially transparent to visible light. This arrangement ensures that the second layer does not adversely affect the user's or observer's view of the first layer (e.g., an indicator).

[0063] The thickness of the second layer (e.g., polymer material) may be about 0.1-0.5 mm, such as about 0.1 to 0.4 mm or about 0.2 to 0.5 mm, such as about 0.2 to 0.4 mm, such as about 0.2 to 0.3 mm.

[0064] The following content can be applied to any of the above embodiments.

[0065] Preferably, the second layer (e.g., a protective layer) may be disposed adjacent to and / or in contact with the first layer.

[0066] The second layer may be adhered (e.g., with an adhesive) to the first layer and / or the substrate of the device.

[0067] The first layer (e.g., an indicator layer) can be disposed on the substrate.

[0068] The substrate may include a self-supporting layer. The substrate may include a film, sheet, etc.

[0069] The first layer can be disposed on the substrate. In use, the substrate can be disposed on the bottom side of the device.

[0070] The second layer may be disposed on the first layer or a portion thereof. In use, the second layer may be disposed on the upper side of the device.

[0071] The first layer may be disposed between the substrate and the second layer.

[0072] The device may be or can be provided as an article, such as a wearable article (e.g., a band, a wristband, a patch, a sticker) or a non-wearable article (e.g., any suitable form of dosimeter article (e.g., a dosimeter card)).

[0073] The first layer and / or the substrate may have a thickness higher than a predetermined level. Typically, the substrate, optionally having the first layer, may have a thickness of at least 0.1 mm.

[0074] The second layer can be adhered to the substrate and / or the first layer (e.g., with an adhesive).

[0075] The colorimetric indicator is capable of exhibiting a color change in response to exposure to UV radiation (e.g., exposure to UVA, UVB, and / or UVC radiation). The triggering radiation may be selected from UVA, UVB, UVC, or a combination thereof.

[0076] The colorimetric indicator may be or may include a UV indicator.

[0077] The colorimetric indicator may be substantially as described in WO 2010 / 070290 (Mills et al.), the contents of which are incorporated herein by reference.

[0078] In one embodiment, the colorimetric indicator may be a UVA and / or UVB indicator. The triggering radiation may be UVA and / or UVB. The triggering radiation may be in the range of 280-400 nm. In this case, the device may be a sunburn indicator, which may be provided in the form of a wearable item (e.g., a band, patch, sticker, tape, etc.).

[0079] In another embodiment, the colorimetric indicator may be a UVC indicator or a UVC dosimeter. The triggering radiation may be UVC. The triggering radiation may be in the range of 100-280 nm. In this case, the device may be a disinfection indicator and / or a sterilization indicator. The device may be a UVC indicator, such as a UVC curing indicator.

[0080] The colorimetric indicator may have a first state associated with a first color. The first state and / or the first color may be associated with the absence of color change. For example, the first state and / or the first color may be associated with the indicator not being exposed to trigger radiation or the indicator being exposed to a predetermined and / or threshold activation level (e.g., below 0.1 mJ / cm²). 2 For example, below 0.5 mJ / cm 2 For example, below 1 mJ / cm 2 The triggering radiation is associated with ).

[0081] The colorimetric indicator may have a second state associated with a second color. This second state and / or the second color may be associated with a complete or final color change. For example, the second state and / or the second color may be associated with the indicator being fully exposed to trigger radiation or the indicator being exposed to an activation level above a predetermined and / or upper limit (e.g., above 0.1 mJ / cm²). 2 For example, below 0.5 mJ / cm 2 For example, below 1 mJ / cm 2 The triggering radiation is associated with ).

[0082] The colorimetric indicator may have one or more intermediate states, each associated with a corresponding intermediate color. The one or more intermediate states and / or intermediate colors may be one or more states and / or colors between the first state and / or the first color and the second state and / or the second color, or may include one or more states and / or colors between the first state and / or the first color and the second state and / or the second color. Each intermediate state and / or intermediate color may be associated with a predetermined level or dose of exposure to triggering radiation.

[0083] Each of the first state and / or the first color, the intermediate state and / or the intermediate color, and the second state and / or the second color may each correspond to a predetermined level or dose of exposure to triggering radiation, or may each be associated with a predetermined level or dose of exposure to triggering radiation.

[0084] The device may further include at least one additional reference color region. The at least one additional reference color region may correspond to the first color, the second color, and any of the intermediate colors. With this arrangement, in use, a user or observer can obtain further visual evaluation by comparing the color of the indicator or the first layer (e.g., its first area) with the color of the at least one additional reference color region. In one embodiment, the at least one additional reference color region may be configured to substantially match the color of the indicator in the second (active) portion. With this arrangement, the additional reference color region may provide another reference area in addition to the reference area defined by the second portion of the device and / or the active portion of the second layer.

[0085] According to a second aspect, a method for manufacturing an indicator device is provided, the method comprising:

[0086] A device having a first layer is provided, wherein the first layer includes a colorimetric indicator; and

[0087] A second layer is applied over at least a portion of the first layer, the second layer comprising or consisting of a protective material, wherein the protective material is transparent or substantially transparent to UV radiation, and wherein the protective material comprises or consists of a glass material or a polymer material.

[0088] The method may include laminating the second layer onto the first layer.

[0089] The method may include (e.g., using an adhesive) bonding the second layer to the first layer.

[0090] The features described regarding the apparatus according to the first aspect can be applied to the method according to the second aspect, and will not be repeated here for the sake of brevity only. Attached Figure Description

[0091] Embodiments of this disclosure will now be given by way of example only and with reference to the accompanying drawings, wherein:

[0092] Figure 1 A schematic diagram of the apparatus according to the first embodiment;

[0093] Figure 2 A schematic diagram of the device according to the second embodiment;

[0094] Figure 3 A schematic diagram of the apparatus according to the third embodiment;

[0095] Figure 4 With or without a protective varnish (upper half), exposure to ~90 mJ / cm² varies.2 Images of the device at UVC radiation dose;

[0096] Figure 5 Comparison of indicator devices using Natgraph UV equipment with and without a quartz glass layer;

[0097] Figure 6 Comparison of using "AUV" UV equipment indicator devices with and without a quartz glass layer;

[0098] Figure 7 shows the use of the "IST" irradiation device at ~30 mJ / cm². 2 A comparison of the dosage indicator devices that do not have a glass cover (7(a)) or have a peripheral portion not covered by glass and a central circular portion covered by a layer of quartz glass (7(b));

[0099] Figure 8 shows the application of an AUV irradiation device at a concentration of ~30 mJ / cm². 2 A comparison of a dosing indicator device that does not have a glass cover (8(a)) or has a peripheral portion not covered by glass and a central circular portion covered by a layer of quartz glass (8(b)).

[0100] Figure 9 shows the use of the "IST" irradiation device at ~150-160 mJ / cm². 2 A comparison of a dosing indicator device that does not have a glass cover (9(a)) or has a peripheral portion not covered by glass and a central circular portion covered by a layer of quartz glass (9(b)).

[0101] Figure 10 shows the application of an AUV irradiation device at a concentration of ~150-160 mJ / cm². 2 A comparison of dosage indicator devices that do not have a glass cover (10(a)) or have a peripheral portion not covered by glass and a central circular portion covered by a layer of quartz glass (10(b));

[0102] Figure 11 illustrates the temperature shielding of the quartz glass layer and ETFE layer on the temperature indicator when exposed to high-temperature UV radiation;

[0103] Figure 12 illustrates the temperature shielding of the quartz glass layer and ETFE layer on the temperature indicator. Detailed Implementation

[0104] refer to Figure 1 The figure shows an indicator device according to the first embodiment, generally marked as 5.

[0105] The device 5 includes a substrate 10. In this embodiment, the substrate 10 is in the form of a film.

[0106] The device has a first layer 20 that includes a colorimetric indicator. In use, the first layer 20 is disposed on the upper side of the substrate 10, that is, on the side of the substrate that is configured to face the radiation source 40.

[0107] The device has a second layer 30 disposed above and covering the first layer 20. Therefore, the second layer 30 covers the indicator. The second layer 30 is adjacent to and in contact with the first layer 20.

[0108] Therefore, any radiation 40 pointing to the indicator within the first layer 30 will interact with the second layer 30 before interacting with the first layer 20.

[0109] The second layer is made of glass or polymer materials.

[0110] In one embodiment, the second layer is made of quartz glass. Advantageously, the quartz glass has a very high purity (silica content), typically at least 99 wt% silica, and therefore is highly transparent to UV radiation. In another embodiment, the second layer may be made of fluorinated polyolefins (such as ETFE, FEP, or PFA).

[0111] Surprisingly, it was found that providing a UV-transparent quartz glass layer 30 on indicator 20 reduced or prevented temperature-induced fluctuations in the indicator's colorimetric properties when exposed to UV radiation 40. Without being bound by theory, it is believed that the glass layer 30 can block or reflect at least some of the heat associated with UV radiation 40 (e.g., heat generated by the UV source), thereby minimizing temperature fluctuations on or within indicator 20 upon exposure.

[0112] Advantageously, the presence of a quartz glass layer also means that the second layer 30 is substantially transparent to visible light, which allows the user or observer to observe the first layer 20 without adversely affecting their view.

[0113] In this embodiment, the second layer 20 has a thickness of 0.3 mm.

[0114] exist Figure 1 In one embodiment, the first layer 20 substantially covers the entire upper surface of the substrate 10, and the second (glass) layer 30 substantially covers the entire upper surface of the first layer 20.

[0115] exist Figure 2 In one embodiment, the first layer 120 covers a portion of the upper surface of the substrate 110, and the second (glass) layer 130 substantially covers the entire upper surface of the first layer 120.

[0116] exist Figure 3In one embodiment, the first layer 220 covers a portion of the upper surface of the substrate 10, and the second (glass) layer 230 substantially covers the entire upper surface of the first layer 220 and also overlaps with the upper surface of the substrate 210.

[0117] The second (glass) layer 230 can be fixed by using an adhesive. Figure 3 An adhesive is shown, which in this embodiment is disposed between the second (glass) layer 230 and the substrate 210. Adhesive 250 is provided to bond the second (glass) layer 230 to the substrate 210.

[0118] refer to Figure 4 The results show the effect of exposure to ~90 mJ / cm² with or without a protective varnish (lower half). 2 When UVC radiation dose, such as Figure 1 An image of the device 305 as generally described in the text.

[0119] In this embodiment, a 0.3 mm thick quartz glass layer 330 is positioned on only a portion of the indicator layer 320 to demonstrate the effect of the presence of the quartz glass layer 330. The glass layer exists in the semi-circular region consisting of regions 302 and 304. Regions 301 and 303 are not covered by the quartz glass layer 330.

[0120] In this embodiment, the UVC indicator layer 320 comprises thymol blue and NaOH as pH indicators, diphenyliodonium chloride (DPIC) as a photoacid generator, and poly(vinyl butyral) as an adhesive.

[0121] Irradiation was performed using a UVC mercury lamp (~254nm) on device 305. The radiation dose was ~90mJ / cm². 2 In the lower half 322 of the device 305 (comprising an uncovered portion 303 and a glass-covered portion 304), a varnish is applied to absorb some radiation. In the upper half 321 of the device 305 (comprising an uncovered portion 301 and a glass-covered portion 302), no varnish is applied, thus creating overexposure of the upper half 321 relative to the lower half 322.

[0122] As can be seen from the lower half, the glass-covered portion 304 did not (as with the uncovered portion 303) reach the final color change as quickly. Furthermore, from the upper half, it can be observed that the portion 302 covered by the glass layer 330 exhibits a strong color change due to the higher exposure level, but does not reach the color change associated with overexposure as shown in the uncovered portion 301.

[0123] Now for reference Figure 5 and Figure 6 The indicator device (generally similar to) is shown. Figure 4 A comparison of the device 305, which has a top not covered by glass and a bottom covered by a layer of quartz glass.

[0124] Figure 5 The results were obtained using Natgraph as the UV irradiation source. Figure 6 The results were obtained using an AUV device as the UV irradiation source. Both machines produce UV radiation, but they generate different amounts of heat during operation ("AUV" is hotter than "Natgraph").

[0125] for Figure 5 and Figure 6 For each of them, the radiation dose is (a) 50 mJ / cm 2 (b) 100mJ / cm 2 and (c) 200mJ / cm 2 .

[0126] refer to Figure 5 It can be seen that for 100mJ / cm 2 and 200mJ / cm 2 Higher exposure dose ( Figure 5 (b) and 5(c)), the glass-covered portion 402 did not reach the final color change as quickly as the uncovered portion 401. However, at 50 mJ / cm 2 At lower exposure doses, the difference is almost negligible.

[0127] refer to Figure 6 It can be seen that for 100mJ / cm 2 and 200mJ / cm 2 Higher exposure dose ( Figure 6 (b) and (c)), the glass-covered portion 502 did not reach the final color change as quickly as the uncovered portion 501. However, at 50 mJ / cm 2 At lower exposure doses ( Figure 6 (a)), the difference is almost indistinct.

[0128] Figures 7 to 10 show the indicator device (generally similar to...) Figure 4 The device 305) has a peripheral portion not covered by glass and a central circular portion (including a "+" mark) covered by a layer of quartz glass.

[0129] For each of Figures 7 to 10, (a) an indicator without a cover and (b) an indicator with a quartz glass cover are shown.

[0130] Figure 7 shows the application of ~30 mJ / cm using the "IST" irradiation device. 2The results of the dosage are shown in Figure 8. Figure 8 shows the dosage results using an "AUV" irradiation device at ~30 mJ / cm². 2 The results of the dosage are shown in Figure 9. Figure 9 illustrates the dosage achieved using the "IST" irradiation device at ~150-160 mJ / cm². 2 The results of the dosage are shown in Figure 10. Figure 10 illustrates the dosage achieved using an AUV irradiation device at ~150-160 mJ / cm². 2 The result of the dosage.

[0131] IST and AUV are two different machines. AUV generates more heat than IST during operation.

[0132] As can be seen from Figures 7 and 8, at lower exposure doses, there is little or no visible difference between the glass-covered portions 602b and 702b and the corresponding uncovered portions 601b and 701b.

[0133] However, as can be seen from Figures 9 and 10, at higher exposure doses, there are visible differences between the glass-covered portions 802b and 902b and the corresponding uncovered portions 801b and 901b.

[0134] Not wanting to be bound by theory, this might be because the two machines operate at 150 mJ / cm 2 The lower ratio is 30mJ / cm 2 Much more heat is generated at lower temperatures. Therefore, there is no visible difference between the covered and uncovered parts at low temperatures (Figures 7 and 8), but there is a significant difference at higher temperatures (Figures 9 and 10). This confirms that the quartz glass cover exhibits the ability to block or repel heat, but not UV radiation.

[0135] Figure 11 shows images of temperature indicators after being exposed to a UV source (H bulb) for a duration of less than 2 seconds (e.g., about 1-2 seconds) using an “AUV” UV device that characteristically emits high heat levels. These images are for (a) an uncovered control 1005a, (b) an indicator 1005b covered with a 0.3 mm thick quartz glass layer, (c) an indicator 1005c covered with a 100 μm thick ETFE layer, (d) an indicator 1005d covered with a 300 μm thick ETFE layer, and (e) an indicator 1005e covered with a 400 μm thick ETFE layer.

[0136] Figure 12 shows another iteration of the same experiment described above with respect to Figure 11.

[0137] As shown in Figures 11(a) and 12(a), it can be seen that when there is no protective layer, indicators 1005a and 1105a show that the temperature rises to about 62.5°C.

[0138] As shown in Figures 11(b) and 12(b), it can be seen that, with the presence of the quartz glass protective layer, indicators 1005b and 1105b only reach about 50°C.

[0139] As shown in Figures 11(c)-11(e) and 12(c)-12(e), it can be seen that in the presence of ETFE layers with thicknesses of 100 to 400 μm, indicators 1005c-1005e and 1105c-1105e reach approximately 50°C only with a 100 μm thick layer, and remain below 50°C with layers of 300 and 400 μm thickness.

[0140] This demonstrates the beneficial effect of both the quartz glass layer and the ETFE layer in blocking heat from the UV source at least partially.

[0141] Ultraviolet transmission studies of various materials

[0142] Various coverings were applied to the radiometer, and the percentage of radiation transmitted through each covering material was measured.

[0143] The following embodiments were studied:

[0144] -Uncovered ("Contrast");

[0145] -0.3mm thick quartz glass layer (“glass”);

[0146] -100μm thick ETFE layer (“F100”);

[0147] -300μm thick ETFE layer (“F300”);

[0148] -400μm thick ETFE layer (“F400”);

[0149] -50μm thick PVC layer (“PC50”);

[0150] -70μm thick PVC layer (“v750”).

[0151] The “PC50” layer is a 50μm thick PVC layer coated with pressure-sensitive acrylic adhesive, sold by Helix® as PC50MICP2.

[0152] The “V750” layer is a 70μm thick PVC layer coated with pressure-sensitive acrylic adhesive, sold by Helix® as PC50MICP2.

[0153] In each case, the measurement is expressed as a percentage of the detected radiation relative to the radiation detected by the control (the uncovered radiometer). All measurements were obtained using the same machine settings.

[0154] These experiments were conducted under “high” and “low” UVC exposure (approximately 140 and 80 mJ / cm², respectively). 2 (This will be carried out under)

[0155] Table 1 below shows the measurement results.

[0156] Table 1:

[0157]

[0158] The following conclusions can be drawn from the results presented in Table 1:

[0159] The 0.3mm thick quartz glass layer provides excellent UV transmission for all types of UV radiation;

[0160] Each ETFE layer (F100, F300, and F400) provides a useful level of UV transmission. Unsurprisingly, increasing the layer thickness reduces UV transmission;

[0161] Other polymer materials, including PC50 and V750, block most UV radiation, despite being thinner than F100, F300, and F400. This suggests that not all polymer materials are expected to allow adequate UV radiation transmission for use in UV indicators.

[0162] - Radiation dose does not affect the relative UV transmittance of each material.

[0163] Alternative fluoropolymer types were tested as protective layers, namely:

[0164] - Alternative types of fluoropolymers include FEP and PFA; and

[0165] - Other types of polymers, namely polyurethane (PU) from Buitink and polyethylene terephthalate (PET) from Folienwerk Wolfen.

[0166] The UV transmittance and temperature resistance of each membrane were measured, and the results are shown in Tables 2 and 3 below. Table 2 shows the results of experiments conducted under “low” UVC exposure, and Table 3 shows the results under “high” UVC exposure (approximately 80 mJ / cm²). 2 The results of the experiment conducted at 140 mJ / cm2.

[0167] Table 2

[0168]

[0169] The following conclusions can be drawn from the results presented in Table 2:

[0170] -ETFE offers good UV transmittance and good temperature control across all thicknesses. Unsurprisingly, increasing the layer thickness reduces UV transmittance;

[0171] Alternative fluoropolymer types, including FEP and PFA, also offer good UV transmission and good temperature control at all thicknesses. Unsurprisingly, increasing layer thickness reduces UV transmission.

[0172] Other polymer materials, including PU and PET, block unacceptably high levels of UV radiation. For example, even a very thin (77 μm) PU film blocks almost as much UV radiation as a 400 μm thick ETFE film. Therefore, these polymer types do not offer the combination of properties provided by the fluoropolymers tested above.

[0173] Table 3

[0174]

[0175] The following conclusions can be drawn from the results presented in Table 3:

[0176] -ETFE offers good UV transmission and good temperature control across all thicknesses. Unsurprisingly, increasing the layer thickness reduces UV transmission;

[0177] Alternative fluoropolymer types, including FEP and PFA, also offer good UV transmittance. Temperature regulation is also achieved for larger thicknesses, particularly for FEP from approximately 200 μm and for PFA from approximately 150 μm. This is thought to be because higher UV exposure causes a greater temperature rise than lower UV exposure (e.g., those tested in Table 2).

[0178] Other polymer materials, including PU and PET, block unacceptably high levels of UV radiation. Therefore, these polymer types do not offer the combination of properties provided by the fluoropolymers tested above.

Claims

1. An apparatus comprising: The first layer contains a colorimetric UV indicator; and A second layer disposed on at least a portion of the first layer, the second layer comprising or being composed of a protective material, wherein the protective material is transparent or substantially transparent to UV radiation, and wherein the protective material comprises or is composed of a glass material or a polymer material.

2. The apparatus of claim 1, wherein the second layer blocks less than about 40%, for example less than about 30%, for example less than about 20%, for example less than about 10%, for example less than about 5%, for example less than about 1% of UV radiation, such as UV-A, UV-B and / or UV-C radiation.

3. The apparatus of claim 1 or claim 2, wherein, The protective material comprises or is composed of polymer materials.

4. The apparatus of claim 3, wherein the polymer material comprises or is composed of a fluorinated addition homopolymer or copolymer.

5. The apparatus according to claim 3 or claim 4, wherein the polymer material comprises or is composed of fluorinated polyolefins.

6. The apparatus according to any one of claims 3 to 5, wherein, The polymer material comprises or is composed of tetrafluoroethylene (TFE) homopolymers or copolymers.

7. The apparatus according to any one of claims 3 to 5, wherein, The polymer material comprises ETFE (ethylene tetrafluoroethylene copolymer) or FEP (fluorinated ethylene propylene), or is composed of ETFE or FEP.

8. The apparatus according to any one of claims 3 to 5, wherein, The polymer material comprises or is composed of perfluoroether homopolymers or copolymers.

9. The apparatus of claim 8, wherein the polymer material comprises or is composed of a perfluoroalkoxyalkane (PFA) polymer.

10. The apparatus according to any one of the preceding claims, wherein, The polymer material has a thickness of about 0.1 mm to 0.5 mm.

11. The apparatus according to claim 1 or claim 2, wherein, The protective material comprises or is composed of glass.

12. The apparatus of claim 11, wherein the glass material comprises glass having a silica content of at least 80 wt% silica, or is composed of glass having a silica content of at least 80 wt% silica.

13. The apparatus of claim 11, wherein the glass material comprises or is composed of quartz glass.

14. The apparatus according to claim 11, wherein, The glass material has a thickness of approximately 0.1-1 mm.

15. An apparatus comprising: The first layer contains a colorimetric UV indicator; and A second layer disposed on at least a portion of the first layer, wherein the second layer covers the colorimetric indicator, and wherein the second layer is made of a glass material, wherein the glass material comprises or is composed of high silica glass.

16. An apparatus comprising: The first layer contains a colorimetric UV indicator; and A second layer disposed on at least a portion of the first layer, wherein the second layer covers the colorimetric indicator, and wherein the second layer is made of a polymeric material comprising, or consisting of, a fluorinated addition homopolymer or copolymer.

17. A method for manufacturing an indicator device, the method comprising: A device is provided having a first layer, wherein the first layer includes a colorimetric UV indicator; and A second layer is applied over at least a portion of the first layer, the second layer comprising or consisting of a protective material, wherein the protective material is transparent or substantially transparent to UV radiation, and wherein the protective material comprises or consists of a glass material or a polymer material.

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