JP7293295B2 - Method for removing methicillin-resistant Staphylococcus aureus - Google Patents

Description

The present invention relates to a method for removing methicillin-resistant Staphylococcus aureus (MRSA), particularly a method for removing MRSA from UV-sensitive surfaces. The method involves using germicidal UV light within the wavelength range of 207 nm to 222 nm, wherein the UV light is delivered by a UV lamp with a lamp cover made from a specific UV transparent borosilicate glass. released. The present invention includes UV transmissive glasses, uses of such UV transmissive glasses, and methods of making same.

BACKGROUND OF THE INVENTION Methicillin-resistant Staphylococcus aureus (MRSA) refers to a group of Gram-positive bacteria that are genetically distinct from other strains of Staphylococcus aureus. MRSA is the cause of multiple human infections that are difficult to treat. MRSA is any strain of Staphylococcus aureus (S. aureus) that has acquired multidrug resistance to β-lactam antibiotics through horizontal gene transfer and/or natural selection. Beta-lactam antibiotics are a broad-spectrum group that includes some penams (penicillin derivatives such as methicillin and oxacillin) and cephems, such as cephalosporins.

MRSA is common in hospitals, prisons and nursing homes, and people with open wounds, invasive devices such as catheters, and weakened immune systems are at increased risk of nosocomial infections. Although MRSA began as a nosocomial infection, it has become not only a community-acquired type but also a livestock infection type.

Recent studies have identified MRSA in many surface waters, such as rivers and lakes, and have shown that MRSA can contaminate drinking water sources, nurseries, schools, hospitals, nursing homes, nursing homes, and other health care facilities. There are increasing opportunities that it can easily propagate to all kinds of areas susceptible to

This is particularly dangerous because typical cleaning systems of sewage and sewage treatment plants are currently not always well equipped to filter or remove multidrug-resistant bacteria from water.

One of the few countries not yet afflicted by MRSA is the Netherlands. An important part of the success of the Dutch strategy has been attempts to clear patients of MRSA before discharge.

Therefore, there is a great need for a removal method that is easy to use and effective against MRSA, especially MRSA present on surfaces that are susceptible to conventional sterilization methods.

Methods for removing MRSA by light have been reported in the art. The so-called "photosensitizer method" is widely used in hospitals and other areas with high MRSA risk (or other bacterial contamination). This method utilizes photosensitizers, mainly dye molecules, which are excited upon exposure to light. When excited by light, these molecules produce reactive oxygen species, which then scavenge the bacteria.

However, not all reported methods using photosensitizers are sufficient to remove enough microorganisms to effectively prevent infection. This is because the photosensitizer may not be concentrated enough to cause significant damage. Additionally, many photosensitizers are hydrophobic. This makes it difficult to disperse photosensitizers in aqueous environments (eg biofilms) where microorganisms are commonly present.

Another method in the art is called "ultraviolet germicidal irradiation" (UVGI), which uses short wavelength ultraviolet (UVC) light to destroy nucleic acids and kill microorganisms by destroying their DNA. It kills or inactivates cells and renders them incapable of performing vital cellular functions. UVGI is used in a variety of applications such as food, air, and water purification.

UVGI devices can produce sufficiently intense UVC light in air or water circulation systems to make the environment inhospitable to microorganisms such as bacteria, viruses, molds and other pathogens. UVGI can be combined with filtration systems to disinfect air and water. The use of UVGI for disinfection has been an accepted practice since the mid-twentieth century. It has been used primarily in medical hygiene and aseptic work facilities.

It is being used more and more to sterilize drinking water and waste water because the containment facility is closed and can be circulated to ensure more UV exposure. In recent years, UVGI has found new uses in air cleaners. Existing UVGI methods use UV light with a wavelength of about 250 nm, for example conventional germicidal UV lamps based on mercury vapor lamps emit at a wavelength of 254 nm.

However, conventional germicidal UV lamps have been reported to be toxic to the eye, produce UV-associated promutagenic DNA lesions in human skin, and be cytotoxic to exposed mammalian skin. there is

Therefore, the risk of adverse effects, including the induction of cancer and even other mutagenic diseases, has led to the widespread use of UVGI for the elimination of MRSA on mammalian skin, e.g., the skin of patients, health care workers, or livestock. Direct use of the law is impeded.

DETAILED DESCRIPTION OF THE INVENTION In recent years, far UVC light has effectively killed bacteria regardless of their ability to resist drugs, but the skin or eye damage effects associated with exposure to conventional germicidal UV have been reduced. reportedly not.

However, the UV absorption of UV light at wavelengths from about 200 nm to about 250 nm is very high in covers that are normally transmissive. For example, UV light is poorly transmitted through conventional glass at wavelengths above 320 nm. Conventional borosilicate glass does not transmit light with wavelengths below 290 nm. These covers are therefore either not tolerant to deep UV light or at least a large amount of energy is required to ensure sufficient UV exposure of the surface to be treated, e.g. the skin to be treated. It has the drawback that This high operating energy also leads to large energy dissipation, increasing thermal stress not only on the cover but also on the entire device. As a result, device life is shortened and maintenance costs are increased.

Thus, a challenge in evaluating prior art methods is the direct MRSA treatment of sensitive surfaces, such as mammalian skin, or other UV-sensitive materials such as certain gases and/or liquids. The objective was to provide a new UVGI method that can apply UV in the deep UVC light for ease of use.

This problem is solved by the methods disclosed herein.

The present invention is a method of removing methicillin-resistant Staphylococcus aureus (MRSA) comprising exposing MRSA to germicidal UV light within the wavelength range of 207-222 nm, wherein the UV light comprises:3. It is irradiated by a UV lamp with a lamp cover made of borosilicate glass with a total platinum content of less than 5 ppm. In some embodiments, the glass may further have a low content of iron, titanium, and other heavy metals of less than 5 ppm each.

UV radiation can cleave organic bonds. Thus, by destroying biological matter, this is not favorable to life. Additionally, many plastics are damaged by UV light due to haze, embrittlement, and/or disintegration. Therefore, UV light can be harmful to many sensitive surfaces or other materials that may be susceptible to UV, such as certain gases and/or liquids.

In humans, excessive exposure to UV radiation can have acute and chronic detrimental effects on the eye's refractive optics and retina. The skin, circadian rhythm, and immune system may also be affected. Skin and eyes are most sensitive to UV damage at 265-275 nm.

Artificial UVC light at a wavelength of about 250 nm, such as that emitted by conventional UVGI lamps, such as mercury vapor lamps, produces UV-associated promutagenic DNA lesions in, for example, human skin models and exposed. It is cytotoxic to mammalian skin. The eye is most sensitive to UV damage in the lower UVC band between 265nm and 275nm. Radiation at this wavelength is almost nonexistent in sunlight, but can be found in welder arc lights and other artificial light sources. Exposure to these can cause "electrical ophthalmia" or "arc-eye" (snow-eye), and can cause the formation of cataracts, pterygium, and palpebral macula.

Accordingly, the wavelengths applied according to the method of the invention are in the range of 207 nm to 222 nm. Ultraviolet (UV) light at about 207 nm has antibacterial properties similar to typical germicidal UV light (254 nm), but is harmful to the exterior of amphibians, reptiles, birds, mammals, or higher animals such as human skin. It does not damage tissue coverage. However, in another embodiment, it may be used to remove MRSA from the outer surface of mollusks (shells) and/or arthropods (exoskeletons).

Due to the limited penetration distance of 207 nm light in biological samples (e.g. stratum corneum) compared to 254 nm light, treated surfaces, particularly mammalian or human skin, e.g. skin of patients and medical personnel It is possible to perform selective antimicrobial treatments without harming the environment.

With respect to the eye, the most important subject in terms of UV risk is the lens. The lens is placed distal to the cornea, and the cornea is sufficiently thick (500 μm) that the transmission of 200 nm light from the cornea to the lens is virtually zero. Even considering the effects on the cornea in terms of snow blindness, eye exposure protection devices, which are now almost common among surgical staff, are expected to provide complete protection of the cornea from 207 nm UV exposure. be.

The proposed bactericidal use of 207 nm UV light in the presence of humans is due to the fact that UV light with a wavelength of about 200 nm is very strongly absorbed by proteins (especially via peptide bonds) and other biomolecules. Because it is based, it has a very limited ability to penetrate biological matter. Thus, for example, the intensity of UV light at 200 nm is reduced by half at only about 0.3 mm of tissue compared to about 3 mm at 250 nm and much longer distances for larger UV wavelengths. In contrast, 200 nm UV light is minimally absorbed by water.

At the cellular level, bacteria are much smaller than almost any human cell. Typical bacterial cells are less than 1 μm in diameter, while typical eukaryotic cells range in diameter from about 10-25 μm.

Thus, although 200 nm UV light can penetrate throughout a typical bacterial cell, it cannot penetrate much beyond the perimeter of the cytoplasm of typical eukaryotic cells, such as human cells, and the nucleus of eukaryotic cells. decays significantly before reaching .

In contrast, longer wavelength light from conventional germicidal lamps can reach human cell nuclei without significant attenuation. Based on these biophysical considerations, radiation from conventional UVC lamps is cytotoxic and mutagenic to both bacteria and human cells, while 200 nm UV light cytotoxic to human cells but much less cytotoxic or mutagenic to human cells.

However, UV light with wavelengths significantly shorter than 200 nm is not useful because these wavelengths can no longer achieve sufficient removal of MRSA. Furthermore, at wavelengths below 200 nm, UV reacts with oxygen to form ozone, an undesirable effect.

UVC light in the range of about 207-222 nm effectively eliminates bacteria regardless of the acquisition of drug resistance, but without the skin and eye damaging effects associated with exposure to conventional germicidal UV.

The term "removal" is used herein to remove greater than 90%, greater than 95%, greater than 99%, greater than 99.9%, or greater than 99.99% MRSA following treatment according to ISO 22196:2011-08-31. used for the reduction of

To achieve such removal, in one embodiment, the present invention provides for MRSA and/or UV exposure of the surface to be treated between 2,000 and 8,000 μW·s/cm ² , between 2,100 and 7, 000 μW·s/cm ² , 2,200-5,000 μW·s/cm ² , or 2,300-3,000 μW·s/cm ² . In one embodiment, a UV exposure of at least about 2,500 μW·s/cm ² provides a 90% reduction in MRSA.

The method of the present invention can be used to remove MRSA on any kind of UV sensitive material sensitive to conventional UV radiation of wavelengths greater than 222 nm. Such a "UV-sensitive material" can be any material in which UV at wavelengths greater than 222 nm, greater than 250 nm, and/or up to 295 nm can cleave organic or inorganic bonds. Such UV-sensitive materials can include any plastic that is damaged due to haze, embrittlement, and/or disintegration by ultraviolet radiation from 222 nm to 295 nm and/or up to 295 nm.

In another embodiment, the UV sensitive material can be susceptible to crosslinking of monomers to produce specific polymers by UV radiation above 222 nm, or above 250 nm, and/or up to 295 nm. In yet another embodiment, the UV sensitive material can be a gas or liquid sensitive to UV above 222 nm, or above 250 nm, and/or up to 295 nm.

In yet another embodiment, the UV sensitive material can be a pharmaceutical composition sensitive to UV above 222 nm, or above 250 nm, and/or up to 295 nm.

In yet another embodiment, the UV-sensitive material is an insect, invertebrate, vertebrate, mammalian or human (e.g., mollusk, fish, amphibian, reptile, bird, mammal, and/or human skin, or lobster or insect). a chitinous exoskeleton from an arthropod)).

The term "biological tissue surface" according to the definition of the present invention therefore refers to any biological surface that can be harmed by UV radiation above 222 nm or above 250 nm and/or up to 295 nm. contain. In one embodiment, the present invention provides biological surfaces that can be harmed by UV radiation outside the wavelength range of 207-222 nm, and biological surfaces that are not harmed by UV radiation within the wavelength range of 207-222 nm. including the target surface.

In the present invention, the term "tissue" is used for any tissue level between cells and complete organs. Tissues are aggregates of similar cells of the same origin and their extracellular matrix that together perform a specific function. Organs are then formed by the functional grouping of multiple tissues together.

Of course, tissues that may be exposed to UV radiation, especially during MRSA ablation methods, should be included. Most often, these tissues are epithelial tissues formed by cells lining the surfaces of organs such as the surface of the skin, the lining of the respiratory tract, reproductive tract, and gastrointestinal tract. The cells that make up the epithelial layer are bound together through tight junctions of the semipermeable membrane. This tissue thus provides a barrier between the organs it covers and the external environment. In addition to this protective function, epithelial tissue may also have specialized functions in secretion, excretion, and absorption. Epithelial tissue helps protect organs from microbes, injury, and fluid loss.

Therefore, the method of the present invention is preferably applicable to conventional UVGI methods, such as UV treatment of MRSA present on UV-sensitive surfaces, such as skin tissue and where eye exposure to UV is unavoidable. Including methods that may not be appropriate.

The term "mammal" is used herein to refer to the mammary glands that make up the class Mammalia and produce milk for feeding (lactating) their offspring in females, the neocortex (region of the brain), fur or hair, and any vertebrate characterized by the presence of three middle ear bones. These features distinguish them from the reptiles and birds that diverged during the Late Triassic, 201 to 227 million years ago. There are approximately 5,450 species of mammals. The largest orders are the orders Rodentia, Bats, and Soricomorpha (such as shrews). The next three are Primates (apes, monkeys, etc.), Cetartiodactyla (terrestrial whales and artiodactyls), and Carnivora (cats, dogs, seals, etc.). This mammalian definition also includes humans.

Thus, the term "mammal skin" refers to any skin of a mammal, including livestock skin, and the term "livestock" generally refers to labor and commodities such as cattle, goats, horses, pigs, and sheep; It is defined as livestock raised in an agricultural environment to produce, for example, meat, eggs, milk, furs, hides, and wool.

In addition, the term "mammalian skin" includes, for example, patients, health care workers, people with weakened or lacking immune systems (elderly, children, post-operative, post-organ transplant, HIV-positive, etc.), Also included is human skin, such as those with high potential exposure to MRSA.

Prior art UV lamp covers are made of sapphire, synthetic quartz, or quartz glass (fused silica glass). However, sapphire is very expensive compared to other transparent materials and cannot be bent, shaped, stretched or fused like glass or metal. In addition, it has very high UV absorption at UVC wavelengths and little transmission at wavelengths below 250 nm.

In one embodiment the glass has a transmission of at least 50%, better at least 60% or at least 70% at 200 nm and/or at least 85% at a wavelength [λ] of 260 nm, 280 nm and/or 310 nm (measured at a thickness of 1 mm).

Due to their high melting points, quartz and fused silica glasses are also more expensive to manufacture because the melting and blowing temperatures and labor are much higher than other standard glasses. Additionally, forms other than tubular must be ground and polished from large blocks. In addition to manufacturing costs, these covers have the disadvantage of requiring large amounts of energy to ensure sufficient UV exposure of the object, gas or liquid being treated.

However, the glasses of the present invention are suitable for forming rods, sheets, discs, tubes, and bars manufactured by casting, Danner, bellows, and/or downdraw processes.

In addition, high operating temperatures may result in sagging and crumbling effects over time, especially when temperatures are cycled at high temperatures, where surface devitrification may become apparent. There is However, this further enhances the weathering effectiveness of the cover, increases UV absorption, and requires higher operating energies to ensure sufficient UV exposure of the object, gas, or liquid. This is a vicious circle.

High operating energy increases thermal stress not only on the cover but also on the entire device, which shortens the life of the device and increases maintenance costs.

The glasses of the invention can have excellent optical properties. In one embodiment, the glass has a refractive index n _d (λ=587.6 nm) between 1.40 and 1.58. The refractive index can be less than 1.50.

The glasses described herein have excellent UV transmission. They may have one or more of the following optical properties:
- UV transmission at 200 nm of at least 60%, in one embodiment at least 62.5% (measured at thickness d=1 mm);
- UV transmission at 207 nm of at least 65%, in one embodiment at least 67.5% (measured at thickness d=1 mm);
- UV transmission at 210 nm of at least 65%, in one embodiment at least 69% (measured at thickness d=1 mm);
- UV transmission at 230 nm (measured at thickness d=1 mm) of at least 75%, in one embodiment at least 81%; and/or - at least 82.5%, in one embodiment at least 85.2% at 250 nm. UV transmission at (measured at thickness d=1 mm).

In one embodiment, the glass has a UV transmission in the wavelength region from 207 nm to 222 nm (measured at thickness d=1 mm) ranging from at least 65% at 207 nm to at least 75% at 222 nm. In one embodiment, the UV transmission ranges from at least 67.9% at 207 nm to at least 76.8% at 222 nm.

The glass and/or glass article preferably has a transmission of at least 50%, preferably at least 70%, at least 80%, or at least 83% at a wavelength of 254 nm. In one embodiment, the transmission at 254 nm is up to 99.9%, up to 95%, or up to 90%. The transmittance is specifically measured at a sample thickness of 1 mm.

For clarity, the indication that transmission is measured at a particular wavelength does not imply that the glass is limited to the specified thickness. Instead, thickness refers to the thickness at which transmission can be measured. By specifying the thickness for the measurement, the values can be reliably compared. Those skilled in the art will appreciate that any suitable thickness of glass can be used for the glass covers and devices described below. Additionally, those skilled in the art will appreciate that transmission can be measured at thicknesses other than 1 mm and that transmission values at 1 mm can be calculated from such measurements.

The present invention utilizes and relates to novel glasses and glass covers (lamp covers, LED cover glasses) that exhibit low UV absorption (i.e. high UVC transmission), thereby reducing operating energy and lowering operating temperatures. Let In addition, the novel glasses and glass covers of the present invention are relatively inexpensive and easy to manufacture, and can be bent, formed, stretched, and fused to ensure a wide variety of shapes. and is resistant to most chemicals, as well as temperature and physical stress.

In one embodiment, the glass has a transmission of at least 60% (measured at a thickness of 1 mm) over the wavelength range of 207 nm to 222 nm, the glass has a total platinum content of 3.5 ppm or less; Some embodiments also have a low iron and titanium content of less than 5 ppm each and an extracted _Na2O equivalent in μg/g glass determined according to ISO 719 of 250 μg/g or less, 200 μg A borosilicate glass having a hydrolysis resistance characterized by no more than 180 μg/g, no more than 180 μg/g, no more than 125 μg/g, no more than 50 μg/g, no more than 40 μg/g, or no more than 25 μg/g.

In one embodiment, Pt contamination in glass (i.e., Pt ⁰ , Pt ²⁺ , Pt ⁴⁺ , and Pt ⁶⁺ , also referred to as “total platinum content”) can reduce UV transmission from 200 nm to about 250 nm. Found. Without wishing to be bound by theory, it is believed that platinum contamination in the glass can cause phase separation through nucleation within the glass. The glasses of the present invention are borosilicate glasses with no or very low metal contamination, especially Pt contamination of less than 3.5 ppm or less than 2.5 ppm. In another embodiment, 0-3.5 ppm, 0-2.5 ppm, 0-2.0 ppm, 0-1.5 ppm, 0-1.0 ppm, 0-0.75 ppm, 0-0.5 ppm, 0- 0.25 ppm is preferred. In a further embodiment, the glass has no Pt contamination.

In yet another embodiment, it was found that TiO ₂ contamination (also called "titanium content") in the glass can also further reduce UV transmission from 200 nm to about 250 nm. Therefore, in one embodiment glasses with a TiO ₂ content of 100 ppm or less, preferably 50 ppm or less are preferred. Preferably, the amount of TiO ₂ should be less than 7 ppm, less than 6 ppm, less than 5 ppm, or less than 4 ppm. In another embodiment, the TiO ₂ content can be 0-6.9 ppm, 0-5.8 ppm, 0-4.7 ppm, 0-3.8 ppm, or 0-2.5 ppm. In optional compositions, a content of 0-1.5 ppm, 0-1.0 ppm, 0-0.75 ppm, 0-0.5 ppm, or 0-0.25 ppm is preferred. In a further embodiment, the glass has no _TiO2 contamination.

In yet another embodiment, it has been found that Fe contamination in the glass can also further reduce UV transmission from 200 nm to about 250 nm. Iron content is expressed herein as parts by weight of Fe ₂ O ₃ in ppm. This value is well known to those skilled in the art by determining the amount of all iron species present in the glass and assuming all iron is present as _Fe2O3 for mass fraction calculations _. can be determined in any way. For example, if 1 mmol iron is found in the glass, the calculated estimated mass corresponds to 159.70 mg Fe ₂ O ₃ . This procedure takes into account the fact that the amount of individual iron species in the glass cannot be reliably determined, or can only be determined with great effort. In some embodiments, the glass comprises less than 100 ppm, especially less than 50 ppm _, or less than 10 ppm _Fe2O3 . In embodiments with particularly low iron content, the Fe ₂ O ₃ content is less than 6 ppm, less than 5 ppm, or less than 4.5 ppm. Optionally, the content of Fe ₂ O ₃ is 0-4.4 ppm, 0-4.0 ppm, 0-3.5 ppm, 0-2.0 ppm, or 0-1.75 ppm. In some embodiments, the content can be 0-1.5 ppm, or preferably 0-1.25 ppm. In _a further embodiment, the glass has no _Fe2O3 contamination.

Thus, in preferred embodiments, the sum of all contamination with Pt, TiO ₂ and/or Fe ₂ O ₃ is less than 20 ppm, in another embodiment less than 18.5 ppm, in another embodiment less than 13.5 ppm, in another embodiment Embodiments of less than 10.5 ppm, and in other embodiments less than 8.5 ppm, are preferred. In another embodiment, the sum of all contamination is 0-8.2 ppm, 0-7.0 ppm, 0-6.0 ppm, 0-5.0 ppm, 0-4.0 ppm, 0-3.0 ppm, 0- Glasses with 2.0 ppm, 0-1.0 ppm, 0-0.5 ppm, 0-0.25 ppm are preferred. In _a further embodiment, the glass is free of contamination with at least one, two, or up to all three of the metals selected from Pt, _TiO2 , and/or _Fe2O3 .

Also, transition elements and/or other contamination with heavy metals such as lead, rhodium, cadmium, mercury, and hexavalent chromium can be kept below 10 ppm, and in another embodiment below 8.5 ppm. In other embodiments, these contaminations can be maintained at 0-8.2 ppm, 0-7.0 ppm, 0-6.0 ppm, 0-5.0 ppm, or 0-4.0 ppm. In other embodiments, the levels of these contaminations can be 0-3.0 ppm, 0-2.0 ppm, 0-1.0 ppm, 0-0.5 ppm, or 0-0.25 ppm. In a further embodiment, the glass is free of transition metal and/or heavy metal contamination.

When a chemical element is referred to herein, the description refers to any chemical form unless otherwise stated in each individual case. For example, a statement that a glass has an As content of _less than 100 ppm means that the sum of the mass fractions of As species present (e.g. _As2O3 , _{As2O5 ,} etc.) does not exceed a value of 100 ppm. .

As used herein, the term "ppm" means parts per million on a weight/weight basis (w/w).

In order to produce glass with adequate UV transmittance, it is necessary to avoid metal contamination during the manufacturing process. Accordingly, the present invention may also relate to a method of making glass with high UV transmission.

In one embodiment, the glasses of the present invention are borosilicate glasses with high UV transmittance and the following additional ranges of physical and chemical parameters.

Unlike quartz, the glasses of the present invention have excellent melting properties, such as low transition temperatures and working points. Examples of suitable glass parameters are a transition temperature T _g (ISO 7884-8 ) can be selected from.

The glass has a T ₁₃ temperature of 410° C. to 550° C., such as 445° C. to 485° C. in one embodiment, 490° C. to 510° C. in another embodiment, or a viscosity η of 10 ¹³ dPa·s (ISO 7884-4). can have a glass temperature (annealing point) of The glass has a softening point of 650° C. to 750° C., for example 690° C. to 715° C. in one embodiment, 700° C. to 725° C. in another embodiment, i.e. the temperature at which the viscosity is 10 ^7.6 dPa s (softening point ) (ISO 7884-3). The glass has a working point of 1000° C. to 1150° C., such as 1060° C. to 1100° C. in one embodiment, 1090° C. to ¹¹⁴⁰ ° C. in another embodiment, i. ISO 7884-2). The temperature-viscosity dependence expressed by one or more of these parameters pertains to the glass' ability to be stretched or otherwise formed into any desired shape, such as a UV lamp cover or a UV-LED cover.

Thus, in one embodiment, the glass has a T _g of 420°C to 465°C: T ₁₃ of 445°C to 485°C, a softening point of 690°C to 715°C, and a working point of 1060°C to 1100°C.

In another preferred embodiment, the glass has a T _g of 460°C to 470°C: T ₁₃ of 490°C to 510°C, a softening point of 700°C to 725°C, and a working point of 1090°C to 1140°C.

The glasses of the invention may have a density ρ of 2-2.5 gcm ^-3 at 25°C. The low density makes glass ideal for portable applications, such as portable MRSA removal devices.

The glasses of the invention can be characterized by a thermal conductivity λ _w of 0.8 to 1.2 Wm ⁻¹ K ⁻¹ at 90° C. and are therefore suitable for use as lamp covers.

UVC glass and UVC glass covers made therefrom have the following additional characteristics:
The term "solarization" refers to a phenomenon in physics in which a material changes in light transmittance after exposure to high-energy electromagnetic radiation, such as ultraviolet light. Clear glass and many plastics turn amber, green, or other colors when exposed to X-rays, and the glass may turn blue after prolonged sun exposure in the desert. Solarization can permanently degrade the physical or mechanical properties of materials and is one of the mechanisms involved in the degradation of plastics in the environment.

The glasses of the invention can exhibit very good resistance to "solarization" (see Examples section) and are therefore very suitable for use as UV glasses. "Solarization" is the decrease in transmission of light in various wavelength ranges caused by exposure to short wavelength UV light. Solarization can cause the glass to become tinted or completely opaque.

ここで、Ｔ（λ）_０は照射前の透過率であり、Ｔ（λ）_ｉは重水素ランプによってｉ時間照射した後の透過率である。α（λ）が小さいほど、ガラスはソラリゼーションに対してより耐性を有している。耐ソラリゼーション性は、本明細書では波長２００ｎｍについて記述される。耐ソラリゼーション性の規定については、本明細書では約０．７０ｍｍ～０．７５ｍｍのサンプル厚が想定されている。これは、このサンプル厚で測定が行われることを意味する。実用新案登録請求されるガラス物品自体は、異なる厚さを有することができる。照射は重水素ランプを用いて行われる。重水素ランプは、非常に短波のＵＶ範囲まで発光する。本明細書で使用されているランプのカットオフ波長は１１５ｎｍである。重水素ランプの出力は約１Ｗ／ｍ^２とすることができる。以下の重水素ランプ（ＤＵＶ）を使用することができる：１１５ｎｍまでの十分な発光のためのＭｇＦ_２フィルターを備えたHeraeus Noblelight GmbH, Type V04, S-Nr.: V0390 30 W。 Thus, "solarization resistance" is the property of a glass to maintain high transmittance at specific wavelengths even after UV irradiation. This can be explained by calculating the induced absorbance α(λ):

where T(λ) ₀ is the transmittance before irradiation and T(λ) _i is the transmittance after i hours of irradiation with a deuterium lamp. The smaller α(λ), the more resistant the glass is to solarization. Solarization resistance is described herein for a wavelength of 200 nm. For the solarization resistance specification, a sample thickness of about 0.70 mm to 0.75 mm is assumed herein. This means that measurements are taken at this sample thickness. The claimed glass article itself can have different thicknesses. Irradiation is carried out using a deuterium lamp. Deuterium lamps emit into the very short-wave UV range. The cutoff wavelength of the lamp used here is 115 nm. The power of deuterium lamps can be about 1 W/m ² . The following deuterium lamp (DUV) can be used: Heraeus Noblelight GmbH, Type V04, S-Nr.: V0390 30 W with _MgF2 filter for sufficient emission up to 115 nm.

The glasses used according to the invention also exhibit very good hydrolysis resistance and high hermeticity.

The phase separation factor is a measure of the property of a glass that changes its hydrolysis resistance as defined in ISO 719 as a result of phase separation. Phase separation occurs when the glass melts under the influence of temperature. It has proven advantageous to choose a glass with a phase separation factor as close to 1 as possible, so that the glass properties of the phase separated glass do not differ significantly from the intact glass in terms of hydrolysis resistance. The phase separation coefficient is affected not only by the glass composition, but also by its thermal history (cooling state).

The phase separation factor E is calculated as follows.

where Equ _roh and Equ _ent are the extracted Na ₂ O equivalents in μg/g glass determined according to ISO 719:1989-12 for non-phase separated and phase separated glasses, respectively. The phase separation factor is a property of glasses. Although this coefficient does not mean that the glass for which the utility model registration is requested has undergone phase separation, if phase separation occurs, the effect on hydrolytic stability will be within the range specified by the coefficient. be. All glasses can be analyzed for their phase separation coefficient. For this purpose, the equivalents of Na ₂ O extracted are measured on phase-separated and non-phase-separated specimens. For measurement purposes, a “phase separated glass” is obtained by holding a glass specimen at 100° C. above the glass transition temperature (T _g ) for 4 hours. This temperature treatment ensures a certain level of phase separation.

Hydrolysis resistance can be expressed as Na ₂ O equivalents extracted in μg per gram of glass. Extracted Na ₂ O equivalent in μg/g glass is determined according to ISO 719:1989-12. This is a measure of the extractability of basic compounds from glass in water at 98°C.

In one embodiment, the glass has a viscosity of 0.1 to 1.65, or 0.2 to 1.65, or 0.35 to 1.65, or 0.40 to 1.65, or 0.65 to 1.65. It has a phase separation factor for its hydrolysis resistance of 65, especially in the range from 0.70 to 1.10. In particular, this factor is at least 0.1, or at least 0.2, or at least 0.35, or at least 0.40, or at least 0.70. Preferably, this factor is close to 1.00, which corresponds to the case of unchanged hydrolysis resistance after phase separation. In one variation, the phase separation factor is up to 1.40, up to 1.25, or up to 1.10.

In one embodiment, the factor is at least 0.70 and at most 1.6. In another variation, the phase separation factor is at least 0.30 and at most 0.5.

Due to the properties of glass, UVC glass covers can be hermetically sealed using, for example, laser glass frit sealing. This hermetic seal is important because many UVGI applications occur in aqueous environments (e.g., biofilm and water treatment), high humidity environments (e.g., sewage systems), and/or environments under high gas pressure or vacuum. is. Additionally, the hermetic sealing allows autoclaving of the final device, e.g. UVC-LED lamps, for use in hospitals, surgeries, laboratories, or other environments where high hygiene standards are required. can do.

This is in contrast to conventional glass, quartz, and/or fused silica glass, which do not have the necessary thermal properties for laser frit sealing and therefore cannot be hermetically sealed. However, the glasses described herein are suitable for achieving a tight, crack-free glass frit connection.

The glasses of the present invention preferably have a product CTE [° C. ⁻¹ ]×T ₄ [° C.] up to 0.0055, more preferably up to 0.0053, or up to 0.0051. The product can be at least 0.0044 or at least 0.0045. These glasses have been shown to exhibit advantageous properties with respect to melt stress and melt behavior.

“T ₄ ” is the temperature at which the glass has a viscosity of 10 ⁴ dPa·s. _T4 can be measured according to methods known to those skilled in the art for determining the viscosity of glasses, eg DIN ISO 7884-1:1998-02. “T ₁₃ ” is the temperature at which the glass has a viscosity of 10 ¹³ dPa·s.

The mean coefficient of linear thermal expansion α (CTE) (20° C.; 300° C. according to ISO 7991) is in one embodiment between 3.0 and 6.0×10 ⁻⁶ K ⁻¹ . The coefficient of thermal expansion (CTE) can be less than 4.5×10 ⁻⁶ K ⁻¹ . It is less than 3.5 to 5×10 ⁻⁶ K ⁻¹ , more preferably 3.75 to 4.75×10 ⁻⁶ K ⁻¹ , more preferably 4.1 to 4.6×10 ⁻⁶ K ⁻¹ , more preferably in the range of 4.1 to 4.5×10 ⁻⁶ K ⁻¹ . This prevents tension in the glass cover as the thermal expansion properties can be matched to the overall thermal expansion properties of the UV device. In one embodiment, the same or similar CTE is selected for both the UVC glass cover and the underlying UV device (eg UVC-LED package).

Preferably, the glass transition temperature is below 500°C. This may range from 400°C to 550°C, more preferably from 410°C to 500°C, in another embodiment from 420°C to 480°C. The processing temperature _T4 is the temperature at which the viscosity of the glass becomes 10 ⁴ dPa·s. The processing temperature _T4 of the glasses of the invention can be less than 1200°C, in some embodiments less than 1125°C. This can be in the range 1000°C to 1200°C, more preferably in the range 1025°C to 1175°C.

In order to ensure that the melting properties, including _Tg and _T4 , are within the desired range, the _ratio of the content (mol%) of _B2O3 to the sum of _SiO2 and _Al2O3 is narrowly controlled _. It may be advantageous to set In advantageous embodiments, this ratio is at least 0.15 and/or at most 0.4.

Another important property of glass is the excellent spatial homogeneity of the refractive index n _d of the material. Optionally, the change in refractive index within the glass may correspond to deformation of the wavefront passing through the glass according to the following equation:
Δs ^{=Δ(nd*d)=Δnd*} _d ⁺ _Δd ^* _nd
where Δs is the wavefront deviation, d is the thickness of the glass, Δd is the change in thickness (difference between maximum and minimum thickness), and _Δnd is the change in refractive index of the glass (maximum refractive index the difference between the index and the minimum refractive index). The invention further includes a glass article having a predetermined wavefront deviation.

Wavefront deviation can be calculated according to the above formula. The refractive index n _d (λ=587.6 nm) and thickness can be determined at 20°C. In one embodiment, the wavefront deviation is determined and/or applied over a surface area of 1 ^cm2 . The wavefront deviation can be determined for glasses with a thickness of 10 mm or less, or for glasses with a thickness of 1 mm or less. Optionally, the thickness can be at least 200 μm. The wavefront deviation can be less than ±0.1 mm, less than ±0.08 mm, in further embodiments less than ±0.035 mm, less than ±25 μm, less than ±15 μm, or less than ±5 μm. Optionally, the wavefront deviation can be from 0.1 μm to 250 μm, or from 1 μm to 100 μm, or from 2 μm to 85 μm.

The wavefront deviation can be measured axially, for example in the case of glass tubes, such as those used in discharge lamps, or transversely, for example in the case of rod sections, such as those used in lenses of UVC-LEDs. can do.

The wavefront can also be measured by a wavefront sensor. This is a device that measures the wavefront aberration of a coherent signal to represent the optical quality or lack thereof in an optical system. Although not bound to any particular method, a very common method is to use a Shack-Hartmann lenslet array.

Alternative wavefront sensing techniques to the Shack-Hartmann system are mathematical techniques such as phase imaging and curvature sensing. These algorithms compute wavefront images from conventional brightfield images at various focal planes without the need for special wavefront optics.

The glass and glass articles according to the invention can have a low content of wavefront deformations (striae, bubbles, streaks, etc.) in the glass. In general, one can distinguish between the overall or long-range uniformity of the refractive index of a material and the short-range deviation from the uniformity of the glass. Striae are spatial short-range uniformity variations in glass. The short range variation is variation over distances of about 0.1 mm up to 2 mm, whereas the spatially long range global homogeneity of the refractive index is across the piece of glass.

In some embodiments, UV-transmitting filters can be used, which filter out certain undesirable UV wavelengths, such as below 207 nm, in some embodiments below 200 nm, and/or above 222 nm, in some implementations. The morphology filters out wavelengths above 250 nm.

A glass for UV covering according to the present invention can allow the shaping of lenses to optically shape UV light, for example for directional focusing of UV light onto a target.

Any beam angle between 10° and 180° is possible. In some embodiments, 10°-20°, 20°-30°, 30°-40°, 40°-50°, 50°-60°, 60°-70°, 70°-80°, 80° ~90° can be utilized. Another embodiment uses 15°-35°, 25°-45°, 35°-60°, 45°-90°, 75°-120°, 90°-145°, 120°-180° be able to.

In some embodiments, such as 90°, 120°, or even 180°, for example when a surface of a particular size or volume or a tube of a particular diameter needs to be decontaminated in one treatment. A fairly wide beam shape of is useful.

In other embodiments, narrow beam shapes such as 10°, 5° or even 1° are useful. For example, a narrow beam shape is used to concentrate the UV exposure on the target site and avoid non-directional unwanted radiation that would reduce the efficiency of the energy-to-irradiation ratio or the exposure of UV-sensitive surfaces to UV light. can be used. One example may be the limited decontamination of certain areas of the eye.

In addition, various lens shapes and beam angles can be used to solve complex MRSA ablation challenges. For example, when UV sensitive surfaces of different sensitivity levels are adjacent to each other and need to be UV exposed in one treatment.

It may be appropriate to treat a patient's skin in multiple areas that have more UV exposure than adjacent areas, for example during wound treatment and/or surgery where the wound itself is exposed to less UV than the surrounding skin. be.

The invention also includes a method of making an LED package having a cover made from the UVC transparent glass of the invention.

An LED package according to the invention may include:
・LED chip;
- Optionally, a substrate on which the LED chip is mounted - for example made of PCB, polymer, inorganic material, in particular ceramic, metal;
- Optionally, a base plate (metal, ceramic, glass-ceramic, rarely polymer) when containing feed-throughs for electrical conductors to contact the LED chip;
a frame (metal, ceramic, glass-ceramic, rarely polymer) containing the LED chip, attached to or surrounding the base plate and forming a cavity of some kind;
- An end portion of the housing (cover) facing outwardly away from the chip that is at least partially transparent and closes the package or is manufactured from a wholly transparent material; at least the transparent portion of the cover is , made of UVC transparent glass as described herein.

Such windows may be flat or have a shape (ie lens shape) to change the path of light.

As mentioned above, UVC-LEDs can be packaged and sealed in some way (eg, laser frit sealing) so that they are autoclavable, sterilizable, and resistant to fluids. Such UVC-LEDs can be used in air and water, surface disinfection; and medical/dental applications.

UVC-LEDs with UVC-transmitting glass as described herein have other advantages compared to conventional UVGI lamps or devices (such as mercury vapor lamps), for example:
- Immediate on/off capability to enable "on-demand disinfection" without wasting energy;
- Directional radiation (especially through the use of lenses that allow control of the beam angle) that allows for "targeted disinfection" in a simple design;
- the durability of the semiconductors to allow their use in rugged and portable devices;
- Low DC power requirements that improve energy efficiency and result in simple and inexpensive electric drives;
Compact packaging for maximum design flexibility;
- Environmentally friendly construction by allowing easy disposal without exposure to harmful mercury;
・High optical performance;
- high radiant power at a defined wavelength;
- CTE matching with AlN;
- Relatively low manufacturing costs;
・Small size.

Traditionally, both low pressure and medium pressure mercury lamps have been utilized in disinfection systems. However, there is a need to replace these light sources with high power and energy efficient UV light, eg UVC-LEDs. UV lamps and devices according to the present invention have greater energy efficiency compared to conventional UVGI lamps or devices. This is because the glasses of the present invention can transmit more than 60% UV light at 200 nm, thus greatly improving the ratio between energy input and radiant output.

This becomes important when using these glasses as covers for UVC-LED lamps. If the energy requirement of a conventional mercury vapor UV lamp is set at 100%, the energy required to produce the same UV radiation with the UVC-LEDs described herein is about 10-30%. In other words, if a conventional UV lamp uses 10W of energy to emit a certain UV intensity, the device herein can use only 1-3W.

As previously mentioned, another advantage of the UVC-transmitting glasses described herein is their high thermal conductivity (λ _w ), which is 0.75-1.25 W·m ⁻¹ at 90°C. K ⁻¹ , in another embodiment about 1.0 W·m ⁻¹ K ⁻¹ . This superior thermal conductivity increases the life of the device as excess heat can easily escape before it harms other parts of the device. This is in contrast to, for example, fused silica, which usually has a low optimum thermal conductivity.

Thus, in one embodiment, the method according to the invention has an Energy Efficiency Index (EEI) according to Regulation (EU) No 874/2012 for non-directional UV lamps of 0.11 or less and for directional UV lamps It may contain a UV lamp with an Energy Efficiency Index (EEI) according to the Regulation (EU) No 874/2012 of 0.13 or less.

The methods described herein can be used to remove MRSA from any type of surface, including UV sensitive surfaces, UV sensitive liquids, and/or UV sensitive gases.

Of course, the methods described herein may be used with viruses (such as influenza or coronaviruses, such as SARS-CoV-2, particularly resistant virus variants such as SARS-CoV2-D614G), bacteria (including spores). It can also be used for the removal of other UV-sensitive pathogenic organisms such as pathogenic yeasts, molds and the like.

Possible uses include hand sanitizers (e.g. personal and public restrooms), room sanitizers in healthcare settings, MRSA removal during or after surgery, wound care, eye care, food disinfection (e.g. food manufacturing). and/or meat, dairy or vegetable counters in supermarkets), disinfection of livestock (especially in the case of intensive animal husbandry, e.g. where batteries are laid), production of pharmaceutical compounds and/or food production processes , storage facilities and/or disinfection of UV sensitive surfaces that often come in contact with many different users, such as keyboards, steering wheels, handrails, toothbrushes, hairbrushes, jewelry, touch devices, shaving razors, or children's toys. You can choose from a list of uses.

The UVC devices disclosed in the present invention can also be used in a wide range of applications as "analytical instruments", such as:
HPLC (High Performance Liquid Chromatography): used in analysis to detect chemicals and compounds in the life sciences;
Spectrometers: used in multiple applications of testing and analysis across biotechnology, life sciences, and environmental monitoring;
• Water quality monitoring sensors: used to detect chemicals in water (eg, during the process of fracking, for general water safety, or prior to disposal of treated wastewater).

In another embodiment, the UVC devices disclosed in the present invention may include devices for "water disinfection." In this respect, UVC LEDs are advantageous compared to conventional mercury lamps, which require long warm-up times (ranging from 50 seconds to 10 minutes) to reach the required germicidal intensity. In addition, frequent on/off cycles can shorten life by 50% or more.

As a result, mercury lamps for these applications must be maintained all day long, increasing lamp replacement frequency and increasing power consumption. In contrast, the instant on-off capability of UVC LEDs enables on-demand disinfection, which greatly reduces power consumption.

Moreover, frequent on/off cycles do not shorten the life of the LEDs, helping to reduce operating and maintenance costs.

Further uses of the UVC devices disclosed in the present invention, particularly for UV sensitive surfaces, liquids or gases, may include:
• Protein analysis, ie bioinformatics studies of protein structure and function using database searches, sequence comparisons, structural and functional predictions.
• Molecular identification, the process of comparing specific DNA fragments between organisms.
In cytometry, or biotechnology, flow cytometry is used in cell counting, cell sorting, biomarker detection, and protein engineering by suspending cells in a liquid stream and passing them through an electronic detection device. laser or impedance-based biophysical techniques.
• Biofilm treatment systems, ie systems that employ the use of bacteria, fungi, algae, and protozoa to remove organic and inorganic material from surrounding fluids.
• Nitrate and/or NOx measurements, typically performed at wavelengths around 230 nm.
- paracetamol concentration measurement, usually performed at a wavelength of about 245 nm; and/or Pityriasis rosea, etc.).

Therefore, in one embodiment, the use of the UV-LED modules of the present invention can be used for water disinfection, analytical instruments (HPLC, spectrometers, water monitoring sensors), air purification, air disinfection, surface disinfection (e.g. keyboard disinfection, escalator disinfection). handrail UV sterilizer), cytometry, molecular identification, protein analysis, biofilm treatment, curing, lithography, plant growth, skin therapy, bacterial detection, drug discovery, protein analysis, induction of skin vitamin D3 production, and/or sterilization can be selected from the group of

Thus, in one aspect, the present invention provides for UV-LED modules such as water disinfection, analytical instruments (HPLC, spectrometers, water monitoring sensors), air purification, air disinfection, surface disinfection (e.g. keyboard disinfection, escalator disinfection). handrail UV sterilizer), cytometry, molecular identification, protein analysis, biofilm treatment, hardening, lithography, plant growth, skin treatment (psoriasis, vitiligo, itching, neurodermatitis, acne, photodermatitis, phototherapy, Pityriasis rosea), bacterial detection, drug discovery, protein analysis, induction of skin vitamin D3 production, and/or sterilization. Regarding.

The glass is preferably borosilicate glass.

In one embodiment, the borosilicate glass comprises the following components (mol % based on oxide):

ここで、「Ｒ_２Ｏ」はアルカリ金属酸化物Ｌｉ_２Ｏ、Ｎａ_２Ｏ、およびＫ_２Ｏを指し、「ＲＯ」はアルカリ土類金属酸化物ＭｇＯ、ＣａＯ、ＢａＯ、およびＳｒＯを指す。 In another embodiment, the borosilicate glass comprises the following components (mol % based on oxide):

Here, " _R2O " refers to the alkali metal oxides _Li2O , _Na2O , and _K2O , and "RO" refers to the alkaline earth metal oxides MgO, CaO, BaO, and SrO.

The glasses of the invention may contain SiO ₂ in a proportion of at least 40 mol %, or at least 60 mol %. _SiO2 contributes to the hydrolytic resistance and transparency of the glass. If the _SiO2 content is too high, the melting point of the glass will be too high. Temperatures _T4 and _Tg also increase sharply. Therefore, the content of _SiO2 should be limited to max 78 mol%, or max 85%.

Preferably, the content of _SiO2 is at least 61 mol%, at least 63 mol%, or at least 65 mol%, at least 68 mol%, at least 69 mol%, or at least 70 mol%. The content can be restricted to a maximum of 75 mol % or a maximum of 73 mol % or a maximum of 72 mol %.

The glasses of the invention contain Al ₂ O ₃ in a proportion of max. 10 mol %. Al ₂ O ₃ contributes to the phase separation stability of the glass, but acid resistance decreases as the ratio increases. In addition _{, Al2O3} increases the melting temperature and _T4 . Therefore, the content of this component should be limited to a maximum of 25 mol %, or a maximum of 9 mol %, or a maximum of 8 mol %, or a maximum of 7 mol %, or a maximum of 5 mol %, or a maximum of 4.5 mol %. In some embodiments, Al ₂ O ₃ is used in minor proportions of at least 2 mol %, at least 2.5 mol %, or at least 3 mol %, or at least 3.25 mol %. _In some embodiments, the glass may be free of _Al2O3 .

The glasses of the invention may contain B ₂ O ₃ in a proportion of at least 12 mol %. _B2O3 has a beneficial effect on the melting properties of _the glass. In particular, the melting temperature is lowered and the glass can be fused with other materials at low temperatures. However, the amount _{of B2O3} should not be too high, otherwise the glass has a strong tendency to phase separate. In addition, too much B ₂ O ₃ adversely affects hydrolysis resistance and the glass tends to have large evaporation losses during manufacture, resulting in knotted glass. Therefore, B ₂ O ₃ should be limited to max 24 mol %, max 22 mol %, or max 20 mol %. The content _{of B2O3} may be at least 5 mol%, at least 12 mol%, or at least 14 mol%.

In a preferred design, the ratio of _the sum of the contents of _B2O3 , _R2O and RO (mol%) to the sum of the contents of _SiO2 and _Al2O3 (mol% ₎ is at most 0.4, especially A maximum of 0.35, more preferably a maximum of 0.34. In one embodiment, this value is at least 0.1, preferably at least 0.2, or at least 0.26. Glasses with the above proportions have excellent properties in terms of hydrolysis resistance and phase separation coefficient, and exhibit only low induced dimming, which is often the case especially when used as UV-transmissive materials. has the advantage of

The glasses of the invention may contain Li ₂ O in proportions of up to 10.0 mol %, or up to 3.0 mol %, or up to 2.8 mol %, or up to 2.5 mol %. Li ₂ O enhances the fusing properties of the glass and beneficially shifts the UV edge to shorter wavelengths. However, lithium oxide tends to evaporate, increasing the propensity for phase separation and increasing the price of the mixture. In a preferred design, the glass contains only minor amounts of Li ₂ O, for example up to 3.0 mol%, up to 2.8 mol%, up to 2.5 mol%, up to 2.0 mol%, or up to 1.9 mol%, or the glass contains Li Does not contain _2O . In certain embodiments, the Li ₂ O content is between 1 mol % and 2 mol %.

The glasses of the invention contain Na ₂ O in a proportion of max 18 mol %, or max 6 mol %. Na ₂ O increases the fusibility of the glass. However, sodium oxide also reduces UV transmission and increases the coefficient of thermal expansion (CTE). The glass may contain Na ₂ O in a proportion of at least 1 mol %, or at least 2 mol %. In one variant, the content of Na ₂ O is up to 5 mol %, or up to 4 mol %. In some embodiments, the glass may be free of _Na2O .

The glasses of the invention contain K ₂ O in proportions of up to 4 mol %. K ₂ O enhances the fusing properties of the glass and beneficially shifts the UV edge to shorter wavelengths. Its content can be at least 0.3 mol %, or at least 0.75 mol %. However, if the content of potassium oxide is too high, the emissive properties of its isotope ⁴⁰ K make the glass have an interfering effect when used in photomultiplier tubes. Therefore, the content of this component should be limited to max 15 mol %, max 10 mol %, max 5 mol %, max 3 mol %, or max 2 mol. In some embodiments, the glass may be free of _K2O .

In an embodiment of the invention, the content ratio of Na ₂ O to K ₂ O in mol % is at least 1.5, in particular at least 2. In one embodiment of the invention, said ratio is at most 4, in particular at most 3. Both oxides serve to improve the fusion properties of the glass. However, if too much Na ₂ O is used, the UV transmittance will decrease. Too much K ₂ O increases the coefficient of thermal expansion. It has been found that the ratios indicated achieve the best results, ie, put the UV transmittance and the coefficient of thermal expansion in the advantageous ranges. In certain embodiments, the ratio is 1.85-3.

The amount of R ₂ O in the glass of the invention is preferably 10 mol % or less, 8 mol % or less, or 7 mol % or less. The glass may contain R ₂ O in an amount of at least 3.5 mol %, at least 4 mol %, or at least 4.5 mol %. Alkali metal oxides increase the cohesiveness of the glass, but at higher proportions they lead to various drawbacks, as discussed above. In certain embodiments, the R ₂ O content is between 4.5 mol % and 6.0 mol %.

The glasses of the invention may contain MgO in proportions of up to 10 mol%, up to 6 mol%, up to 4 mol%, or up to 2 mol%. Although MgO is advantageous with respect to cohesiveness, at high proportions it has problems with the desired UV transmission and has been found to be prone to phase separation. A preferred design does not contain MgO.

The glasses of the invention may contain CaO in proportions of up to 16 mol%, up to 6 mol%, up to 4 mol%, or up to 2 mol%. Although CaO is advantageous with respect to weldability, it has been found to have problems with the desired UV transmission at high proportions. Preferred forms contain no or only little CaO, such as at least 0.1 mol %, at least 0.3 mol %, or at least 0.5 mol %.

The glasses of the invention may contain SrO in proportions of up to 4 mol %, up to 1 mol %, or up to 0.5 mol %. Although SrO is advantageous for weldability, it has been found to have problems with the desired UV transmission at high proportions. A preferred design does not contain SrO.

The glasses of the invention may contain BaO in proportions of up to 12 mol %, or up to 4 mol %, or up to 2 mol %. BaO improves hydrolysis resistance. However, if the content of barium oxide is excessively high, phase separation occurs, resulting in instability of the glass. Preferred embodiments contain BaO in an amount of at least 0.1 mol%, at least 0.3 mol%, or at least 0.4 mol%. In certain embodiments, the BaO content is between 0.3 mol % and 1.5 mol %. In some embodiments, the glass may be free of BaO.

Alkaline earth oxides RO have been shown to have a large effect on phase separation tendency. Therefore, in certain design configurations, special attention is paid to the components of these components and their relationship to each other. Therefore, the ratio of BaO in mol% to the sum of the contents of MgO, SrO and CaO in mol% should be at least 0.4. Preferably, this value is at least 0.55, or at least 0.7, or at least 1.0. In particularly preferred forms the value is at least 1.5, or even at least 2. BaO offers the greatest advantages in terms of phase separation and hydrolysis resistance compared to other alkaline earth metal oxides. However, the ratio should not exceed 4.0 or 3.0. Advantageously, the glass contains at least small amounts of CaO and BaO and is free of MgO and SrO. In certain embodiments, the ratio is between 0.7 and 2.2.

In particular, advantageous properties are obtained when the ratio of the proportion of CaO in the glass to BaO in mol % is less than 2.0. In particular, this ratio should be less than 1.5 or less than 1.0. In some embodiments the ratio is even lower, especially less than 0.8, or less than 0.6, and in preferred designs the ratio is at least 0.3. In certain embodiments the ratio is between 0.4 and 1.4.

In one variation, the glass has a ratio of B ₂ O ₃ to BaO in mol % of at least 8 and at most 45. Preferably the ratio is at least 10, or at least 11, and in preferred designs the ratio is limited to a maximum of 42, or 40, or 39. In another embodiment, the ratio may be limited to a maximum of 15 or 14. In particular, the ratio is between 10 and 45, or in another embodiment between 11 and 42, and in certain embodiments the ratio is between 11 and 16. In another embodiment, the ratio is 35-45.

Glasses with the above ratios show good properties in terms of hydrolysis resistance and phase separation coefficient, and also low induced absorbance.

The proportion of RO in the glasses of the invention can be at least 0.3 mol %. Alkaline earth metal oxides are advantageous for weldability, but at high proportions they have been found to have problems with the desired UV transmission. In one variant, the glass contains up to 3 mol % RO. In one embodiment, the proportion of RO is 1-3 mol %.

The sum of the contents of alkaline earth metal oxides and alkali metal oxides in mol %, RO+R ₂ O, can be limited to a maximum of 10 mol %. Advantageous designs can contain these components in amounts up to 9 mol %. Preferably, the content of these oxides is at least 4 mol%, at least 5 mol%, or at least 6 mol%. In one embodiment, the proportion of RO+R ₂ O is 6-8 mol %. These components increase the propensity for phase separation and reduce the hydrolysis resistance of the glass to a very high degree.

The ratio of the content in mol% of _B2O3 to the sum of the content of _R2O and RO in mol% can be at least 1.3, at least 1.5, or at least 1.8 _. . The ratio can be limited to a maximum of 6, a maximum of 4.5, or a maximum of 3. In one embodiment, the ratio of B ₂ O ₃ /(RO+R ₂ O) is between 1.8 and 3.5. The presence of too much alkali or alkaline earth oxides relative to _B2O3 can lead to the formation of alkali or alkaline earth borates during phase separation of the glass _. It has proven advantageous to adjust the above ratios.

To ensure that the melting properties, including _Tg and _T4 , are within the desired range, the ratio of the content of _B2O3 to the sum of the content of _SiO2 and _Al2O3 in _mol % _is It may be advantageous to set within a narrow range. In advantageous designs, this ratio is at least 0.15 and/or at most 0.4. In one embodiment, the ratio of B ₂ O ₃ /(SiO ₂ +Al ₂ O ₃ ) is between 0.17 and 0.3.

The ratio of the proportion in mol % of the total alkali metal oxides R ₂ O to the total alkaline earth metal oxides RO is preferably greater than 1, in particular greater than 1.1 or greater than 2. In this design, this ratio is 10 max, 7 max, or 5 max. In one embodiment, the ratio is 2-4.

The glasses of the invention may contain F ^{2 −} in a content of 0-6 mol %. Preferably, the F 2 ^- content is at most 4 mol %. In some designs, at least 1 mol %, or at least 2 mol % of this component is used. Component F 2 ⁻ improves the fusing properties of the glass and influences the UV edge towards shorter wavelengths.

The glasses of the invention may contain Cl ^{2 −} in a content of less than 1 mol %, in particular less than 0.5 mol %, or less than 0.3 mol %. Suitable lower limits are 0.01 mol % or 0.05 mol %.

The glasses of the invention may contain ZnO with a content of less than 5 mol %, in particular less than 2.5 mol %, or less than 1 mol %. Suitable lower limits are 0.01 mol % or 0.05 mol %. In some embodiments, the glass may be free of ZnO.

The glasses of the invention may contain ZrO ₂ with a content of less than 5 mol %, less than 2.5 mol % or in particular less than 1 mol %. Suitable lower limits are 0.01 mol % or 0.05 mol %. In some embodiments, the glass may be free of _ZrO2 .

The glasses of the invention may contain SnO ₂ with a content of less than 3 mol %, in particular less than 2 mol %, or less than 1 mol %. Suitable lower limits are 0.01 mol % or 0.05 mol %. In some embodiments, the glass may be SnO ₂ free.

In this specification, when it is stated that a glass does not contain a certain component or does not contain a specific component, it means that this component can be present only as an impurity at most. do. This means that no significant amount has been added. An insignificant amount is an amount less than 0.5 ppm, preferably less than 0.25 ppm, preferably less than 0.125 ppm, most preferably less than 0.05 ppm.

In one embodiment, the glass has less than 10 ppm, in particular less than 5 ppm, or less than 1 _{ppm Fe2O3} . In one embodiment, the glass has less than 10 ppm, in particular less than 5 ppm, or less than 1 ppm _TiO2 . In one embodiment the glass has less than 3.5 ppm, in particular less than 2.5 ppm, or less than 1.0 ppm arsenic. Glasses containing less than 3.5 ppm antimony, less than 2.5 ppm antimony, or less than 1.0 ppm antimony are preferred. In addition to adversely affecting UV transmission and solarization, arsenic and antimony in particular are toxic and environmentally hazardous and should be avoided.

In a particularly preferred design, the borosilicate glass contains the following components (mol % based on oxide):

In another particularly preferred form, the glass comprises the following mol % components:

In another particularly preferred form, the glass comprises the following mol % components:

Glass articles can be manufactured by drawing processes known for glass tubes and glass rods. A person skilled in the art will choose an appropriate manufacturing process, such as ingot casting for bars, floating or down-draw for manufacturing plates, etc., depending on the shape desired. Preferably, the cooling of the glass during processing is adjusted to obtain the desired properties.

In one embodiment, the glass article is manufactured using the Danner or Bellow process. In the bellows process, the glass melt flows vertically (in the direction of gravity) downward through a forming tool made up of exit rings and needles. A forming tool forms a female mold (mold) of the produced cross-section of the glass tube or glass rod. In the manufacture of glass tubes, a needle is placed as a forming part in the center of a forming tool.

The difference between the bellows process and the downdraw process is that, firstly, the glass melt in the bellows process diverges horizontally after leaving the forming tool, and secondly, in the bellows process, the blown air flow passes through a passageway. That's what needles have. As with the Danner method, the blown air keeps the resulting glass tube from collapsing. In the downdraw process, the solidified glass melt is separated without prior reorientation. Since there is no turning, the use of blown air during manufacture of the glass tube can also be avoided.

In one embodiment, the present invention relates to glass articles made from the glasses disclosed herein. The thickness of the glass article, particularly in the case of a glass tube, may be at least 0.1 mm or at least 0.3 mm. Thickness can be limited to a maximum of 3 mm or a maximum of 2 mm. The outer diameter of the glass article, eg, a glass tube or glass rod, can be up to 50 mm, up to 40 mm, or up to 30 mm. The outer diameter can in particular be at least 1 mm, at least 2 mm or at least 3 mm. In one embodiment, the article has a thickness of at least 3 mm and/or up to 20 mm. Optionally, the thickness is at least 5mm, at least 6mm, or at least 8mm. Thickness may be limited to a maximum of 20 mm, a maximum of 16 mm, a maximum of 14 mm, or a maximum of 12 mm. In one embodiment the article has a length and a width, in particular the length is greater than the width. The length may be at least 20 mm, at least 40 mm, or at least 60 mm. Optionally, it is up to 1000 mm, up to 600 mm, up to 250 mm, or up to 120 mm. Preferably, the length is between 20mm and 1000mm, between 40mm and 600mm, or between 60mm and 250mm. The width may be at least 10 mm, at least 25 mm, or at least 35 mm. Optionally, the width is up to 575mm, up to 225mm, or up to 110mm. Preferably the width is between 10 mm and 575 mm, between 25 mm and 225 mm, or between 35 mm and 110 mm.

In view of the above, the invention also relates to the following embodiments:
In one aspect, the invention provides a method for eliminating methicillin-resistant Staphylococcus aureus (MRSA) comprising exposing MRSA to germicidal UV light within the wavelength range of 270 nm to 222 nm, said The UV light is applied by a UV lamp with a lamp cover made of borosilicate glass with a total platinum content of less than 3.5 ppm.

In another aspect, the MRSA exposed to germicidal UV light is present on a UV sensitive material that is sensitive to UV radiation above 222 nm.

In yet another aspect, the UV-sensitive material is a biological tissue surface such as an eye or skin of an animal, wherein the animal is selected from insects, invertebrates, vertebrates, mammals, and/or humans.

In yet another aspect, said removal of MRSA after treatment is greater than 99% according to BS ISO 22196:2011-08-31.

In yet another aspect, said UV exposure for MRSA ranges from at least 2,000 to 8,000 microwatt-seconds per square centimeter (μW·s/cm ² ).

In yet another aspect, all or part of the UV lamp cover is molded in the shape of a lens.

In another aspect, the invention relates to a glass having a transmission of at least 60% (measured at a thickness of 1 mm) over the wavelength range of 207 nm to 222 nm, the glass having a total platinum content of 3.5 ppm or less. Borosilicate glass. In some embodiments, 3 ppm or less, 2.5 ppm or less, 2 ppm or less. The glass also has a hydrolysis resistance characterized by an extracted Na ₂ O equivalent in μg/g glass determined according to ISO 719 of 250 μg/g or less. In some embodiments, 180 μg/g or less, 120 μg/g or less, 50 μg/g or less.

In yet another aspect, the glass is at least 40%, at least 50%, at least 55%, at least 60% at 200 nm, and/or at least 55%, at least 60%, at least 65% at 210 nm, and/or at 230 nm. (1 mm thick measured in). In one embodiment, the transmission at 200 nm is up to 95%, up to 85%, or up to 70%.

For many applications, the most uniform transmission possible in the UV range is desired. The glasses of the invention have a ratio of transmission at 254 nm to transmission at 200 nm (each measured at a sample thickness of 1 mm) of at least 1.00 and at most 2.00, in particular at most 1.65 or at most 1.50. can have

In yet another aspect, the glass comprises a total content of one or more UV blocking impurities of less than 10 ppm. In some embodiments, it is less than 8 ppm, even less than 5 ppm.

In yet another aspect, the glass comprises one or more UV blocking impurities selected from rhodium, lead, cadmium, mercury, hexavalent chromium, iron, titanium, and any combination thereof.

In yet another aspect, the glass comprises a total platinum content of less than 1.0 ppm.

The wavefront deviation may be less than ±0.1 mm, less than ±0.08 mm, and in further embodiments less than ±0.035 mm, less than ±25 μm, less than ±15 μm, less than ±5 μm. Optionally, the wavefront deviation can be from 0.1 μm to 250 μm, or from 1 μm to 100 μm, or from 2 μm to 85 μm.

In yet another aspect, the glass has a refractive index n _d between 1.450 and 1.580.

In yet another aspect, the glass comprises the following components (mol %) in the amounts indicated:

In another aspect, the present invention is for UV-LED modules such as water disinfection, analytical instruments (HPLC, spectrometers, water monitoring sensors), air purification, air disinfection, surface disinfection (e.g. keyboard disinfection, escalator handrails) UV sterilizer), cytometry, molecular identification, protein analysis, biofilm processing, curing, lithography, plant growth, skin treatment (psoriasis, vitiligo, pruritus, neurodermatitis, acne, photodermatitis, phototherapy, rose pityriasis skin), bacterial detection, drug discovery, protein analysis, induction of cutaneous vitamin D3 production, and/or sterilization.

In one aspect, the invention relates to a glass article comprising or consisting of the glass described herein. In one embodiment, the glass article has at least one polished surface. Optionally, the glass article has at least one chamfered edge. The polished surface can have a surface roughness Ra of less than 10 nm or less than 5 nm. A chamfered edge is more impact resistant and particularly more resistant to chipping than a non-chamfered edge.

Thermal and/or Chemical Strengthening Optionally, the manufacturing process includes chemically and/or thermally strengthening the glass article. "Tempering" is also called "hardening" or "toughening".

Preferably, the glass article is toughened, in particular thermally and/or chemically toughened, on at least one surface. For example, it is possible to chemically strengthen glass articles by ion exchange. In this process, small alkali ions within the article are usually replaced by larger alkali ions. Potassium often replaces the smaller sodium. However, it is also possible that very little lithium is replaced by sodium and/or potassium. Optionally, alkali ions can be replaced with silver ions. Another possibility is that the alkaline earth ions exchange with each other according to the same principle as the alkali ions. Preferably, the ion exchange takes place in a molten salt bath between the article surface and the salt bath. A pure molten salt such as molten _KNO3 can be used for the exchange. However, mixtures of salts or mixtures of salts with other ingredients can also be used. The mechanical durability of the article can be further enhanced if a selectively tailored compressive stress profile is built up within the article. This can be accomplished by a single or multi-step ion exchange process.

Replacing small ions with large ions or thermally strengthening creates a compressive stress in the corresponding zone that decreases from the surface to the center of the glass article. The maximum compressive stress is just below the glass surface and is also called CS (compressive stress). CS is stress and is expressed in units of MPa. The depth of the compressive stress layer is abbreviated “DoL” and is given in μm. Preferably, CS and DoL are measured using an Orihara FSM-60LE device.

In one embodiment CS is greater than 100 MPa. More preferably CS is at least 200 MPa, at least 250 MPa, or at least 300 MPa. More preferably CS is up to 1,000 MPa, up to 800 MPa, up to 600 MPa, or up to 500 MPa. Preferably CS ranges from greater than 100 MPa to 1,000 MPa, from 200 MPa to 800 MPa, from 250 MPa to 600 MPa, or from 300 MPa to 500 MPa.

In one embodiment, the glass article is thermally strengthened. Thermal strengthening is typically performed by quenching the hot glass surface. Thermal strengthening has the advantage of being able to form a deeper compressive stress layer (higher DoL) than chemical strengthening. As a result, the thinner the compressive stress layer, the more easily scratches cannot enter into the compressive stress layer, so that the glass is less likely to be scratched.

The glass or glass article can undergo thermal strengthening processes, for example, after melting, forming, annealing/cooling processes, and low temperature post-treatment steps. In this process, a glass body (e.g. a glass article or pre-product as described above), e.g. a glass sheet, is preferably horizontally fed or suspended in an apparatus and heated to a temperature above the transition temperature _TG of up to 150°C. Rapidly heated to temperature. The surface of the glass body is then quenched, for example by blowing cold air through a nozzle system. As a result of the quenching of the glass surfaces, they are frozen in an extended network, while the interior of the vitreous body cools slowly and has time to shrink further. This creates a compressive stress in the surface layer and a tensile stress in the interior. The amount of compressive stress is determined by CTE _glass (average coefficient of linear thermal expansion below Tg), CTE _liquid (average coefficient of linear thermal expansion above Tg), strain point, softening point, Young's modulus, and between cooling medium and glass surface depends on various glass parameters such as the amount of heat transfer in the glass body, as well as the thickness of the glass body.

Preferably, a compressive stress of at least 50 MPa is generated. As a result, the flexural strength of the glass body can be doubled to tripled compared to untempered glass. In one embodiment, the glass is heated to a temperature of 750-800° C. and rapidly tempered in a stream of cold air. Optionally, the blowing pressure can be 1-16 kPa. Compressive stress values of, for example, 50-250 MPa, especially 75-200 MPa, are achieved in commercial systems using the glass or glass article described herein.

In one embodiment, the glass article has a compressive stress layer with a compressive stress of at least 50 MPa, in particular at least 75 MPa, at least 85 MPa or at least 100 MPa. A glass article can have a compressive stress layer on one, two, or all of its surfaces. The compressive stress of the compressive stress layer may be limited to a maximum of 250 MPa, a maximum of 200 MPa, a maximum of 160 MPa, or a maximum of 140 MPa. These compressive stress values can be present especially in heat strengthened glass articles.

In one embodiment, the depth of the compressive stress layer of the glass article is at least 10 μm, at least 20 μm, at least 30 μm, or at least 50 μm. In certain embodiments, this layer may even be at least 80 μm, at least 100 μm, or at least 150 μm. Optionally, DoL may be limited to a maximum of 2,000 μm, a maximum of 1,500 μm, a maximum of 1,250 μm, or a maximum of 1,000 μm. In particular, DoL can be between 10 μm and 2,000 μm, between 20 μm and 1,500 μm, or between 30 μm and 1,250 μm. In one embodiment, the glass article is thermally strengthened with a DoL of at least 300 μm, at least 400 μm, or at least 500 μm. Optionally, DoL may be up to 2,000 μm, up to 1,500 μm, or up to 1,250 μm. In one embodiment, the DoL is between 300 μm and 2000 μm, between 400 μm and 1,500 μm, or between 500 μm and 1,250 μm.

Embodiments The present invention relates to glasses that are resistant in multiple respects. Particularly resistant glasses are particularly useful when the glass is subjected to special requirements. This is the case, for example, in extreme environments. Extreme environments are in particular applications that require special resistance, durability and safety requirements, such as those requiring explosion protection.

In one embodiment, the present invention relates to glass articles particularly suitable for use in extreme environments. Articles may be sheets, discs, tubes, rods, ingots, or blocks. In preferred embodiments, the article is in the form of a sheet or disc.

Optionally, the glass article comprises glass having a transmission (measured at a thickness of 1 mm) of at least 60% over the wavelength range of 207 nm to 222 nm, the glass having a total platinum content of 3.5 ppm or less and and a hydrolysis resistance of 250 μg/g or less characterized by an extracted Na ₂ O equivalent expressed in μg per gram of glass determined according to ISO 719, and a glass article comprising at least It has a thickness of 0.3 mm, in particular at least 3 mm and/or at most 20 mm.

In extreme environments, thick glass is more mechanically stable than thin glass, so it may be useful to impart a certain minimum thickness to the glass article. However, thicker glass absorbs most of the UV radiation that enters the glass, resulting in heat generation. In environments where highly flammable materials are used, high heat generation can be a problem. Glass articles with low induced dimming at 200 nm and/or 254 nm have the advantage that they remain highly transmissive at the wavelengths of interest even after extended use, avoiding extreme heat generation. .

According to the invention, glass articles can also be used in UV lamps for disinfecting surfaces in extreme environments. In one embodiment, glass articles are used in UV lamps (especially as covers) used to disinfect the work site. The site of action may be an object that many people touch, such as a handle, especially a door handle. The UV lamp can be positioned, for example, so that it irradiates the site of action. In this case, constant proximity to the site of action is unavoidable. Therefore, at this point there is a risk that the glass article will break on impact. For this reason, mechanical resistance is required. Although increasing the thickness of the glass article can improve mechanical durability, this reduces the transmittance of the article and significantly increases heating of the glass during UV lamp operation. Excessive heating should be avoided, which in turn is positively impacted by very good transmission and low induced dimming. Excessive heat is unsafe due to user burns and risk of explosion. In principle, the risk of burns can be reduced by increasing the distance, but this must be compensated for by higher radiation intensity, with the drawback of greater heat generation as well.

The present invention also relates to UV lamps and the use of glass articles in UV lamps, especially for disinfecting in extreme environments, especially for disinfecting sites of action, such as those that are touched by many people. It has proven advantageous to maintain a minimum distance of 5 cm, in particular 7.5 cm or 10 cm, between the surface to be disinfected and the glass article. When using the glass articles described herein, at least 1.0 mW/cm ² , at least 1.5 mW/cm ² , at least 2.5 mW/cm ² , at least 3.0 mW/cm ² , or at least A power density of 3.5 W/cm ² can be set. The site of action is the surface to be disinfected. Optionally, the power density is up to 20 mW/cm ² , up to 15 mW/cm ² or up to 10 mW/cm ² . Specifically, power density is the power that can be measured at the site of action as UV radiation, particularly UV-C radiation, mediated by a UV lamp. Preferably, the site of action is disinfected on a regular basis. This means that the site of action is not irradiated continuously, but only intermittently. For example, the irradiation interval can be triggered by contact, presence, or actuation by the user. For example, the irradiation interval can be at least 1 second, at least 5 seconds, at least 10 seconds, or at least 20 seconds. Optionally, the irradiation interval lasts up to 10 minutes, up to 5 minutes, up to 2 minutes, or up to 1 minute.

In one embodiment, the UV lamp and/or the glass article has a thermally optimized structure, the thickness of the glass article and the UV transmittance of the glass article is 70 mm away from the glass article (article relative to the light source). The active site (located on the opposite side) was irradiated with a medium pressure mercury lamp (e.g. Philips HOK 4/120) of 120 W/cm and an arc length of 4 cm at a UVC power density of 17.27 mW/ ^cm2 and an ambient temperature of 20°C. is selected such that the temperature of the surface of the glass article facing the site of action does not exceed 45° C. when irradiated for 5 seconds at . In one embodiment, the radiation passes vertically through the glass article. That is, light enters the glass article substantially perpendicular to the surface facing the light source, and/or light exits the glass article substantially perpendicular to the surface of the glass article facing the site of action. . In particular, the temperature does not exceed the values of 42.5°C, 40°C or 37.5°C. In one embodiment, said temperature limit is not exceeded even after 10 seconds, 20 seconds, 30 seconds, 45 seconds, 60 seconds, 90 seconds, 120 seconds, 150 seconds or 180 seconds of irradiation. This property describes how strongly a glass article heats up when vertically illuminated by a commonly used UV light source. It is realized that UV lamps with lamp covers made from glass articles do not get dangerously hot. UVC power density refers to the power density provided by radiation in the UVC range (280-200 nm). Medium pressure mercury lamps also emit light at other wavelengths, but are not considered here when discussing UVC power density. Measurements are made in ambient atmosphere. For the sake of clarity, the properties described do not limit the use of UV lamps or glass articles to medium pressure mercury lamps.

In one embodiment, the glass article meets the fracture pattern requirements according to DIN EN 12150-1:2020-07. The entire article or a portion of the article can be examined, and the article can deviate from the specified criteria and be smaller than indicated there, as long as the area considered is exceeded. The area considering the failure pattern can be specifically 40 mm x 40 mm or 25 mm x 25 mm. In one embodiment, the glass article shatters into 25 or more pieces, in particular 30 or more or 40 or more pieces under the above conditions. It is advantageous for the article to break into many pieces, as smaller pieces reduce the risk of injury if broken. Fracture patterns can be influenced, for example, by selection of glass composition, cooling conditions (heat shrinkage), adjustment of stress in the glass, and/or strengthening of the article.

In one embodiment, the present invention relates to a glass article comprising a glass having a transmission (measured at a thickness of 1 mm) of at least 60% over the wavelength range of 207 nm to 222 nm, wherein the glass has a transmittance of 3.5 ppm or less. A borosilicate glass having a total platinum content and a hydrolysis resistance of 250 μg/g or less characterized by an extracted Na ₂ O equivalent expressed in μg/g glass determined according to ISO 719; Furthermore, the glass article has a thickness of at least 0.3 mm, in particular at least 3 mm and/or at most 20 mm, and furthermore the article has a compressive stress of at least 50 MPa on at least one surface and a thickness of 40 mm determined according to DIN EN 12150-1. and a fracture pattern characterized by a x40 mm area breaking into 25 or more pieces.

Figure 1 shows the transmittance curves of the "glass no. 1" of the invention at different thicknesses (1 mm and 0.34 mm) and different UV wavelengths; Figures 4a to 4c show the possible use of UV-transmissive glass in various LED packages a)-f). Figures 4a to 4d show possible uses of UV-transmissive glass in various LED packages a)-e); The figure which shows the transmittance|permeability curve of "glass no. 1" of this invention. The figure which shows the transmittance|permeability curve of "comparative glass 1." The figure which shows the transmittance|permeability curve of "comparative glass 2."

Example
Example 1
Both glasses were melted under reducing conditions in a quartz glass crucible and homogenized with a quartz glass stirrer. All melts were placed in a 465° C. cooling furnace and cooled to room temperature at a rate of 30 K/h.

The melt "Glass No. 1" was melted at 1610°C, refined at 1620°C for 60 minutes, then stirred at the same temperature for 30 minutes and then left at 1620°C for 120 minutes. As a result, the glass was as void-free as possible.

After casting, a clear glass cast block was obtained from the Pt-free form (“Glass No. 1”).

In addition to the chemical analysis of the glass, transmission curves of the glass were recorded at at least two different locations on the cast block. The refractive index was also determined as a function of wavelength in order to be able to calculate the transmission curve with the same sample thickness.

The following table shows exemplary glasses in mol % according to the present disclosure.

Two 'comparison glasses' were made with the same composition as 'Glass No. 1' and containing:
"Comparative glass 1 (C1)": 7.9 ppm _Fe2O3 and _8.3 ppm _TiO2 and 3.5 ppm Pt.
"Comparative glass 2 (C2)": 3.3 ppm _Fe2O3 and _20.9 ppm _TiO2 and 3.8 ppm Pt.

・Glass No. UV transmittance test using Glass No. 1. The UV transmittance of 1 was tested at various thicknesses and wavelengths. The following transmittances were measured at a thickness of 0.34 mm.
・200nm-73.5%
・207 nm-77.5%
・222 nm-83.0%

The following transmittances were measured at a thickness of 1 mm.
・200nm-62.2%
・207 nm-67.5%
・222 nm-77.0%

After that, glass no. 1 was compared to comparative glasses C1 and C2. Pt contamination was 3.5 ppm and 3.8 ppm respectively.

The transmittance at 200 nm is the glass No. Compared to 1, it decreased from 60-65% to about 50% for glass C1 and about 20-30% for glass C2. This indicates not only the significant impact of Pt contamination, but also that other contaminants such as iron and titanium affect the transmittance.

Manufacture of UV Lamps and/or UV-LED Lamps UVC transparent glass no. 1 was used to manufacture a UVC-LED lamp. The package size of the LED package was 3.5×3.5 mm.

Other features of the LED package:
・Substrate: AlN with cavity (approximately 1.0 mm in height)
・Thickness of window: 0.3mm (flat)
・Solder material: Au/Sn, Au/Ni

Additionally, a UVC transparent encapsulant material was used to further protect and cover the LED. Such encapsulating materials can be copolymers of methyl methacrylate and acyloxyimino methacrylate esters. Poly-(methyl methacrylate-co-3-methacryloyl-oximino-2-butanone) was used in this example.

The glass cover is laser fritted onto the package surface to allow UVC-LED lamps to be autoclavable even at high gas pressures due to favorable thermal properties and to be usable in environments containing high humidity or high gas pressures. can be sealed.

• Energy efficiency test as a UV-LED cover An LED lamp was compared with a conventional LED lamp. LEDs made using the present invention have been found to have approximately 30% higher energy efficiency than conventional UV lamps.

• MRSA removal test The surface on which MRSA-CFU (colony forming units) were present was irradiated with the UVC-LED lamp of the present invention. It was irradiated with 2,500 μW·s/cm ² UVC at 200 nm for 10 minutes. After UVC treatment for 10 minutes, less than 1% of MRSA-CFU could be identified.

Therefore, glass no. 1 is hydrolysis resistant characterized by high UV transmittance and equivalents of _Na2O extracted in water at 98°C of 20, 25, 30, 50, 100, 180 and/or 250 µg/g or less It is a glass with the characteristics.

Example 2
Other inventive glass compositions with high UV transmission and hydrolysis resistance are shown in the table below. Contents of components are given in mol %. Other physical properties of glass are also described.

The following table shows the solarization resistance (induced absorbance) after exposure to deuterium lamps for 48 hours and 96 hours, respectively. Transmittance is measured with a glass thickness of 0.7 to 0.75 mm.

The following table shows approximate transmission values for several glasses after exposure to deuterium lamps for 48 hours and 96 hours, respectively.

Detailed Description of the Drawings Figure 1 shows the transmission curves of the "glass no. 1" of the invention at different thicknesses (1 mm and 0.34 mm) and different UV wavelengths.

FIG. 2 shows possible uses of UV-transmissive glass in various LED packages a)-f). The shape of the glass lens [1] allows focusing or dispersion of the UV light, depending on the specific application. Furthermore, the cover glass [1] can surround the UV source (eg UV-LED) [4] so that the UV light is also emitted laterally (see Fig. 2c)-f)). A reflective element on the back of the casing [3] can improve the luminous efficiency. As the casing [3], an aluminum nitride ceramic (AlN ceramic) with high thermal conductivity can be used. The LED [4] and glass cover [1] can be metal soldered [2] to the casing [3].

In Figure 3, instead of metal soldering [2] the glass to the casing [3] (see Figure 3a), the UV transparent glass of the present invention [1] can also be attached to the casing by laser frit sealing [6]. (See FIGS. 3b)-e)). The LED [4], which can be metal soldered [2] to the casing [3], can be further completely encapsulated in a transparent encapsulant [5]. Such encapsulating materials may be copolymers of methyl methacrylate and acyloxyimino methacrylate esters. Poly-(methyl methacrylate-co-3-methacryloyl-oxyimino-2-butanone) was used in the examples. In that case, the laser frit sealing [6] completely protects the LED elements from environmental influences, and as a result, this configuration is suitable for harsh environments, especially when strongly acidic cleaners and/or disinfectants are regularly used. Perfect for the conditions. In this case also, aluminum nitride ceramic (AlN ceramic) with high thermal conductivity can be used as the casing [3]. Again, reflective elements on the back of the casing [3] can improve the luminous efficiency.

4-6 show the transmission curves of different glasses. Transmission at 200 nm decreases from 60-65% (inventive "glass no. 1") to about 50% ("comparative glass no. 1") and 20-30% ("comparative glass no. 2") bottom. This demonstrates the significant impact of platinum and other contaminants on UV transmission.

FIG. 4 shows the transmittance curve of the “glass no. Two measurements were made on the same cast glass block at different locations. Variation in transmission measurements for the same glass is due to cast block non-uniformity.

FIG. 5 shows the transmittance curve of "Comparative Glass 1" with a platinum content of 3.5 ppm, iron of 7.9 ppm and titanium of 8.3 ppm. Two measurements were made on the same cast glass block at different locations. Variation in transmission measurements for the same glass is due to cast block non-uniformity.

FIG. 6 shows the transmittance curve of "Comparative Glass 2" with a platinum content of 3.8 ppm, iron of 3.3 ppm and titanium of 20.9 ppm. For "Comparative Glass 2" three measurements were made on the same cast glass block at different locations. Variation in transmission measurements for the same glass is due to cast block non-uniformity.

Claims (17)

A method of removing methicillin-resistant Staphylococcus aureus (MRSA), said method comprising exposing said MRSA to germicidal UV light within the wavelength range of 207 nm to 222 nm, said UV light comprising: irradiated by a UV lamp with a lamp cover made of borosilicate glass having a total platinum content of less than .5 ppm and a total content of Pt, TiO ₂ and Fe ₂ O ₃ of less than 13.5 ppm. . 3. The method of claim 1, wherein the exposed MRSA is on a UV sensitive material sensitive to UV radiation above 222 nm. 3. Claim 1 or 2, wherein said UV-sensitive material is a biological tissue surface such as an eye or skin of an animal, said animal being selected from insects, invertebrates, vertebrates, mammals and/or humans. the method of. 4. The method of any one of claims 1-3, wherein the removal of MRSA after treatment according to BS ISO 22196:2011-08-31 is greater than 99%. 5. The method of any one of claims 1-4, wherein the UV exposure of the MRSA ranges from at least 2,000 to 8,000 microwatt-seconds per square centimeter (μW·s/cm ² ). 6. A method according to any one of claims 1 to 5, wherein all or part of the cover of the UV lamp is shaped in the form of a lens. 1 g of UV covering glass having a transmission of at least 60% (measured at a thickness of 1 mm) over the wavelength range of 207 nm to 222 nm with a total platinum content of less than 3.5 ppm and a glass determined according to ISO 719 hydrolysis resistance characterized by an extracted _Na2O equivalent in μg/g of less than or equal to 250 μg/g and a Pt, _TiO2 , and _Fe2O3 content of less than 13.5 _ppm The UV covering glass, which is a borosilicate glass having the sum of - has a transmission of at least 60% at 200 nm and/or has a transmission of at least 85% at a wavelength [λ] of 260 nm, 280 nm and/or 310 nm (measured at a thickness of 1 mm),
A glass according to claim 7, - having a wavefront deviation (peak-to-valley) of less than ±0.1 mm and/or - having a refractive index n _d between 1.450 and 1.580. - the total content of one or more UV blocking impurities is less than 10 ppm,
- Optionally, the glass of claim 7 or 8, wherein the UV-blocking impurities are selected from lead, cadmium, mercury, rhodium, hexavalent chromium, iron, titanium and any combination thereof. 10. The glass of any one of claims 7-9, wherein the total platinum content is less than 1.0 ppm. The glass contains the following components in the indicated amounts (mol%):

A glass according to any one of claims 7 to 10, comprising: 12. A glass article for UV covering , made from a glass according to any one of claims 7 to 11, having a thickness of at least 0.3 mm, in particular at least 3 mm and/or at most 20 mm. 13. Glass article according to claim 12, wherein the article is thermally or chemically strengthened and in particular has a compressive stress of at least 50 MPa on at least one surface. 14. Glass article according to claim 12 or 13, having a fracture pattern characterized by a 40 mm x 40 mm area breaking into 25 or more pieces, determined according to DIN EN 12150-1. For UV-LED modules, e.g. water disinfection, analytical instruments (HPLC, spectrometers, water monitoring sensors), air purification, air disinfection, surface disinfection (e.g. keyboard disinfection, escalator handrail UV sterilizer), cytometry, molecular identification, protein analysis, biofilm processing, hardening, lithography, plant growth, skin treatment (psoriasis, vitiligo, pruritus, neurodermatitis, acne, photodermatitis, phototherapy, pityriasis rosea), bacterial detection, 15. A glass article according to any one of claims 12 to 14 as a hermetically sealed lens cap in applications selected from the group of drug discovery, protein analysis, induction of skin vitamin D3 production and/or sterilization. use. 16. Use of the glass article according to claim 15, wherein the thickness of the glass article and the UV transmittance of the glass article are located on the opposite side of the glass article with respect to the light source and 70 mm away from the article. When the action site was irradiated with a UVC power density of 17.27 mW/cm ² using a medium pressure mercury lamp of 120 W/cm and an arc length of 4 cm at an ambient temperature of 20° C. for 5 seconds, the Said use, wherein the temperature of the surface of the glass article is selected not to exceed 45°C . 15. The glass article of any one of claims 12-14, wherein the thickness of the glass article and the UV transmittance of the glass article are located on the opposite side of the glass article with respect to the light source and the 17.27 mW/cm using a medium pressure mercury lamp of 120 W/cm and an arc length of 4 cm with an active site 70 mm away from the article. ² said glass article is selected such that the temperature of the surface of said glass article facing said site of action does not exceed 45°C when irradiated for 5 seconds at an ambient temperature of 20°C at a UVC power density of .

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