Boron aluminosilicate glass with excellent visual appearance

Abstract

The invention relates to boroaluminosilicate glass with excellent visual appearance and a method for producing the glass. The invention also relates to the use of such a glass, in particular for pharmaceutical packaging, for example for pharmaceutical containers such as glass vials, glass ampoules, glass cartridges or glass syringes or the like.

Description

Technical Field

[0001] The present invention relates to a boroaluminosilicate glass having an excellent visual appearance and a method for producing the glass. The present invention also relates to the use of the glass, in particular for pharmaceutical packaging, for example, pharmaceutical containers such as glass vials, glass ampoules, glass cartridges or glass syringes. Background Art

[0002] Glass products used in the medical field, particularly for pharmaceutical applications, are subject to stringent quality standards. Products used in primary pharmaceutical packaging, such as vials, ampoules, cartridges, and syringes, must exhibit high transparency, good sterilization properties, and excellent chemical resistance. Furthermore, the glass must not alter the quality of the contained material or any material it comes into contact with beyond specified thresholds. This means that the glass must not release any substances that could, for example, impair the efficacy and stability of the contained drug, or even render it toxic.

[0003] Therefore, it is desirable to provide glass for pharmaceutical containers that has high chemical resistance, particularly hydrolytic resistance. Such ideal glass should, in particular, have high transparency and be cost-effective to produce. Furthermore, particularly in the pharmaceutical packaging sector, it is desirable for the glass to have a neutral white color.

[0004] The glass commonly used in the pharmaceutical industry is borosilicate glass (so-called neutral glass), the main components of which are silicon oxide and boron oxide, but may also contain aluminum oxide, alkali metal oxides and alkaline earth metal oxides.

[0005] To achieve a good visual appearance, it is also important to keep the number of bubbles in the glass very low. This is usually achieved through refining. Previously, refining agents containing oxides of As and / or Sb were used. For safety reasons, new refining agents have been developed, particularly those based on Cl.

[0006] Another refining agent is CeO2. However, CeO2 has the disadvantage of imparting a yellow tint even in moderate concentrations. Therefore, glass refined solely with CeO2 cannot meet the stringent requirements for a neutral white color on the one hand and a low number of bubbles on the other. CeO2 contents that are acceptable with respect to tint do not achieve the desired refining effect. CeO2 contents that are acceptable with respect to the refining effect are associated with an undesirable tint.

[0007] It would be desirable to provide a glass that overcomes the disadvantages of the prior art. In particular, it would be desirable to provide a glass that has an excellent visual appearance due to a low bubble content, a neutral white color, and does not produce a light ring when processed into pharmaceutical containers.

[0008] These objectives are addressed by the subject matter disclosed in this application. Summary of the Invention

[0009] In a first aspect, the present invention relates to a glass comprising the following components in the following proportions (in wt %):

[0010] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0011] The Cl content is in the range of 75 ppm (by weight) to 800 ppm (by weight), the CeO2 content is in the range of 10 ppm (by weight) to <2000 ppm (by weight), the sum of the Cl and CeO2 contents is at least 800 ppm (by weight), and the weight ratio of the CeO2 content to the Cl content is at most 10.

[0012] In a second aspect, the present invention relates to a glass comprising the following components in the following proportions (in wt%):

[0013] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0014] The glass has a color position in the CIE 1931 color space such that, with a sample thickness of 25 mm and using an illuminant "D65" at 6500 K for a CIE standard observer within 2° arc of the fovea, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.60.

[0015] In a third aspect, the present invention relates to a glass comprising the following components in the following proportions (in wt %):

[0016]

[0017]

[0018] The glass exhibits a bubble count of less than 1000 bubbles / cm in the melt termination test (MTT test). 2 .

[0019] In a fourth aspect, the present invention relates to a glass comprising the following components in the following proportions (in wt %):

[0020] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0021] The total volume of bubbles per kilogram of glass is less than 1000mm 3 / kg.

[0022] In a fifth aspect, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0023] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0024] The hydrolysis resistance of the glass corresponds to less than 75% of the HGA1 limit specified in ISO 720:2020(E).

[0025] In the sixth aspect, the present invention relates to a method for manufacturing glass according to any one of the first, second, third, fourth and fifth aspects, which method particularly includes the step of processing the glass melt by a down-draw method, an overflow melting method, a re-drawing method, a float method, a rod drawing method or a tube drawing method, in particular a Danner method or a Velotin method or a vertical down-draw method.

[0026] In a seventh aspect, the present invention relates to use of the glass according to any one of the first, second, third, fourth and fifth aspects or the glass manufactured according to the method according to the sixth aspect in a pharmaceutical container or as a pharmaceutical container.

[0027] In an eighth aspect, the present invention relates to a glass product, in particular, a pharmaceutical container comprising the glass according to any one of the first, second, third, fourth and fifth aspects or the glass manufactured according to the method of the sixth aspect.

[0028] Unless otherwise stated, the contents disclosed herein also refer to various aspects of the present invention. In particular, unless otherwise stated, the term "embodiment" used herein refers to all aspects of the present invention.

[0029] Unless otherwise specified, portions expressed as "ppm" in this disclosure mean "ppm (by weight)".

[0030] The glass of the present disclosure according to any aspect has an excellent visual appearance and is particularly suitable for use as a pharmaceutical container. In particular, the glass combines a favorable color impression with a low bubble content and does not produce a light ring when processed into a pharmaceutical container.

[0031] The glass of the present invention according to any aspect has an excellent color impression and is particularly suitable for use as a pharmaceutical container.

[0032] The color impression can be described using the CIE 1931 color space, which represents the color impression by a combination of three values: x, y, and z (chromaticity coordinates). The measurements are preferably performed in accordance with DIN 5033 (part 1 (DIN 5033-1: 2009-05), part 2 (DIN 5033-2: 1992-05), and part 3 (DIN 5033-3: 1992-07)) using illuminant "D65" at 6500 K for a CIE standard observer within a 2° arc around the fovea (CIE 19312° standard observer). In short, the X, Y, and Z standard spectral values ​​are taken from the CIE 1931 color space system table and multiplied by the measured transmittance values ​​to obtain the corresponding tristimulus values.

[0033] The chromaticity coordinates x, y and z define a color location or color position in a color space, which is obtained by normalizing the sum of x+y+z to 1. Therefore, the x-value, y-value and z-value are all positive, and the sum x+y+z=1. The CIE 1931 color space chromaticity diagram represents a color space, where the x-axis represents the x-value and the y-axis represents the y-value. By calculating z=1-xy, the z-value can be inferred from any given pair of x-values ​​and y-values. The point x=y=z=1 / 3 represents the so-called "white point", which defines the color "white". High x-values ​​represent reddish colors. High y-values ​​represent greenish colors. High z-values ​​represent bluish colors. Each chromaticity is represented as a specific color location in the color space. The color location of an additive mixed color is on the straight line connecting the components. To accurately represent the color stimulus specification, the tristimulus value Y is used as a brightness reference value (DIN 5033, Part 1 (DIN 5033-1:2009-05)) by dividing the sum of all Y values ​​by a ratio (=21.293658). The resulting value is normalized to a maximum value of 100. This value indicates whether the glass appears lighter or darker to the human eye compared to the comparison probe.

[0034] In certain embodiments, the x value in the CIE 1931 color space is at least 0.20 and at most 0.50, for example, at least 0.25 and at most 0.47, when the sample thickness is 25 mm, 750 mm, and / or 1500 mm. In certain embodiments, the y value in the CIE 1931 color space is at least 0.20 and at most 0.60, for example, at least 0.27 and at most 0.53, when the sample thickness is 25 mm, 750 mm, and / or 1500 mm. In certain embodiments, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.60, for example, the x value is at least 0.25 and at most 0.47, and the y value is at least 0.27 and at most 0.53, when the sample thickness is 25 mm, 750 mm, and / or 1500 mm.

[0035] As mentioned above, a neutral white color impression is desirable, particularly in the pharmaceutical packaging sector. In contrast, a yellow-brown color impression is undesirable. x = y = z = 1 / 3 represents a neutral white color impression and is therefore a potential embodiment of the present invention when the sample thickness is 25 mm, 750 mm, and / or 1500 mm. However, a color impression slightly different from neutral white is actually more preferred. In fact, a slightly greenish impression is preferred, particularly over a reddish one. Therefore, in certain embodiments, the y value is higher than the x value. In certain embodiments, when the sample thickness is 25 mm, 750 mm, and / or 1500 mm, the ratio of the y value to the x value is greater than 1.00, particularly greater than 1.01, greater than 1.02, greater than 1.03, or even greater than 1.04. However, the ratio of the y value to the x value should not be too high, lest the glass appear overly green. In certain embodiments, when the sample thickness is 25 mm, 750 mm and / or 1500 mm, the ratio of the y value to the x value ranges from 1.01 to 1.50, specifically from 1.02 to 1.40, 1.03 to 1.30 or 1.04 to 1.20.

[0036] In general, the smaller the sample thickness, the smaller the ratio of y-value to x-value. In certain embodiments, when the sample thickness is 25 mm, the ratio of y-value to x-value ranges from 1.01 to 1.10, 1.02 to 1.09, 1.03 to 1.08, or 1.04 to 1.07. In certain embodiments, when the sample thickness is 750 mm, the ratio of y-value to x-value ranges from 1.05 to 1.30, or 1.10 to 1.25. In certain embodiments, when the sample thickness is 1500 mm, the ratio of y-value to x-value ranges from 1.05 to 1.50, or 1.10 to 1.45.

[0037] In certain embodiments, when the sample thickness is 25 mm, the range of x values ​​is 0.20 to 0.40 or 0.25 to 0.35. In certain embodiments, when the sample thickness is 750 mm, the range of x values ​​is 0.20 to 0.45 or 0.25 to 0.40. In certain embodiments, when the sample thickness is 1500 mm, the range of x values ​​is 0.20 to 0.50 or 0.25 to 0.47. In certain embodiments, when the sample thickness is 25 mm, the range of y values ​​is 0.25 to 0.40 or 0.30 to 0.35. In certain embodiments, when the sample thickness is 750 mm, the range of y values ​​is 0.30 to 0.50 or 0.35 to 0.45. In certain embodiments, when the sample thickness is 1500 mm, the range of y values ​​is 0.30 to 0.60 or 0.35 to 0.55. In certain embodiments, when the sample thickness is 25 mm, the y value ranges from 0.30 to 0.35, and / or when the sample thickness is 750 mm, the y value ranges from 0.35 to 0.45. In certain embodiments, when the sample thickness is 25 mm and / or 750 mm, the x value ranges from 0.20 to 0.50 or 0.25 to 0.45; when the sample thickness is 25 mm and / or 750 mm, the y value ranges from 0.20 to 0.50. In certain embodiments, when the sample thickness is 25 mm, 750 mm, and / or 1500 mm, the x value ranges from 0.20 to 0.50 or 0.25 to 0.47; when the sample thickness is 25 mm, the y value ranges from 0.30 to 0.35, and / or when the sample thickness is 750 mm, the y value ranges from 0.35 to 0.45.

[0038] Generally, the y-value when the sample thickness is 750 mm may be higher than the y-value when the sample thickness is 25 mm. In certain embodiments, the difference between the y-value when the sample thickness is 750 mm and the y-value when the sample thickness is 25 mm is in the range of 0.01 to 0.15, for example, 0.02 to 0.10.

[0039] When referring to "sample thickness", the thickness refers to the thickness of the sample on which the corresponding parameter can be measured. The sample thickness does not refer to the actual thickness of the glass or glass product, and the thickness of the glass or glass product is in no way limited to the sample thickness.

[0040] In certain embodiments, the y-value of the glass at a sample thickness of 750 mm is at most 50%, at most 40%, at most 30%, or at most 20% higher than the y-value of the glass at a sample thickness of 25 mm. In certain embodiments, the y-value at a sample thickness of 750 mm is 5.0% to 40% higher than the y-value at a sample thickness of 25 mm, for example, 10% to 30% higher.

[0041] Glass according to any aspect of the present invention has an extremely low bubble content. Bubble content can be described in various ways. On the one hand, bubble content refers to the number of bubbles in the glass or glass product. For example, this can be expressed as the total volume of bubbles per kilogram of glass. On the other hand, low bubble content can also be attributed to the refinability of the glass.

[0042] The term "bubble" as used in the present disclosure refers to bubbles that are detectable by visual inspection with the naked eye. Thus, the term "bubble" as used herein refers to bubbles that extend for more than 80 μm in at least one spatial direction.

[0043] Some glasses can be refined better than others. The glasses of the present invention have very favorable refinability. This property can be determined by the so-called Melt Termination Test (MTT test). In this test, the synthetic composition (mixture of glass raw materials) of each glass composition to be tested is filled into a separate crucible. The crucible is placed in a furnace preheated to 1450°C and held there for one hour. The furnace is then heated to 1600°C at a heating rate of 200K / h and held at this temperature for 15 minutes.

[0044] According to the procedure shown, the glass raw material mixture is completely melted without any residue and subjected to preliminary refining. However, the refining is not complete.

[0045] Afterwards (after holding the furnace at 1600°C for 15 minutes), the crucible is removed and placed on a refractory surface. The molten glass cools rapidly within the crucible, essentially being "frozen" in a state that provides information about the refining results.

[0046] This method essentially ends refining early, leaving a readily detectable number of bubbles in the glass, even when a combination of refining agents is used, which removes more or less all bubbles after refining is complete. Therefore, this test is more sensitive than a test that completes refining when comparing the effects of different refining agents.

[0047] After the glass had completely cooled, a cylindrical sample was taken from each glass for analysis of the number of bubbles. To analyze the number of bubbles, the cylindrical sample was sawn in half and the vertical sawn surface of one of the resulting half cylinders was polished for further analysis of the number of bubbles in the glass.

[0048] The number of bubbles was determined by visual inspection of a 1 cm x 1 cm area located in the center of the polished saw face at a depth of 2.5 cm (the depth of a semi-cylinder of glass). The sample was prepared so that the area represented by the saw face was located 1 cm below the surface of the glass melt in the crucible.

[0049] The number of bubbles in a 1 cm x 1 cm area within a depth of 2.5 cm is expressed as bubbles per square centimeter. The corresponding volume is approximately 2.5 cm 3 , but not exactly 2.5cm 3 The reason is that the depth of 2.5 cm is the depth of the half cylinder. This is the maximum depth of the sample. The sample depth at the edge of the sample is slightly less, only about 2.4 cm. However, the sample volume is approximately 2.5 cm. 3 Therefore, according to the MTT test, the number of bubbles per square centimeter is roughly equivalent to the number of bubbles per 2.5 cm 3 For example, 50 bubbles per square centimeter is roughly equivalent to 2.5 cm 3 There are 50 bubbles, or about 20 bubbles per cubic centimeter.

[0050] In certain embodiments, the glass of the present invention has fewer than 1000 bubbles per square centimeter in the MTT test, such as at most 950 bubbles per square centimeter, at most 900 bubbles per square centimeter, at most 850 bubbles per square centimeter, at most 800 bubbles per square centimeter, at most 750 bubbles per square centimeter, at most 500 bubbles per square centimeter, at most 250 bubbles per square centimeter, at most 150 bubbles per square centimeter, at most 100 bubbles per square centimeter, at most 75 bubbles per square centimeter, at most 50 bubbles per square centimeter, at most 40 bubbles per square centimeter, at most 30 bubbles per square centimeter, at most 20 bubbles per square centimeter, at most 15 bubbles per square centimeter, or at most 10 bubbles per square centimeter. In certain embodiments, the glass of the present invention has at least 1 bubble per square centimeter, such as at least 2 bubbles per square centimeter or at least 5 bubbles per square centimeter in the MTT test. In certain embodiments, the number of bubbles in the MTT-test can be, for example, in the range of 1 to <1000 bubbles per square centimeter, 1 to 950 bubbles per square centimeter, 1 to 900 bubbles per square centimeter, 1 to 850 bubbles per square centimeter, 1 to 800 bubbles per square centimeter, 1 to 750 bubbles per square centimeter, 2 to 500 bubbles per square centimeter, 2 to 250 bubbles per square centimeter, 2 to 150 bubbles per square centimeter, 2 to 100 bubbles per square centimeter, 2 to 75 bubbles per square centimeter, 5 to 50 bubbles per square centimeter, 5 to 40 bubbles per square centimeter, 5 to 30 bubbles per square centimeter, 5 to 20 bubbles per square centimeter, 5 to 15 bubbles per square centimeter, or 5 to 10 bubbles per square centimeter.

[0051] Therefore, as described according to the MTT test, the glass of the present invention has excellent refinability. The MTT test is a test performed on refining that has ended prematurely. Therefore, in this test, a certain number of bubbles may remain in the glass. In fact, this requires quantification of the number of bubbles. Unlike the MMT test procedure, glass intended for practical use (for example, glass products such as pharmaceutical containers) is usually produced under complete refining. After refining is completed, the number of bubbles in the glass is very small. In particular, glass with essentially no bubbles can be obtained. However, a small amount of bubbles may still remain in the glass. This can be quantified as the total volume of bubbles per kilogram of glass. The bubbles in the glass can be detected by visual inspection, in particular automatic visual inspection. The total volume of bubbles per kilogram of glass can be determined based on the size of the bubbles and the weight of the glass.

[0052] In certain embodiments, the total volume of bubbles per kilogram of glass is less than 1000 mm 3 / kg, for example, up to 950mm 3 / kg, up to 900mm 3 / kg, up to 875mm 3 / kg, up to 850mm 3 / kg, up to 825mm 3 / kg, up to 800mm 3 / kg, up to 750mm 3 / kg, up to 500mm 3 / kg, up to 400mm 3 / kg, up to 350mm 3 / kg, up to 300mm 3 / kg, up to 275mm 3 / kg, up to 250mm 3 / kg, up to 225mm 3 / kg, up to 200mm 3 / kg, up to 190mm 3 / kg, up to 180mm 3 / kg, up to 170mm 3 / kg or up to 160mm 3 In certain embodiments, the total volume of bubbles per kilogram of glass is at least 1 mm 3 / kg, for example at least 2mm 3 / kg, at least 5mm 3 / kg, at least 10mm 3 / kg, at least 25mm 3 / kg, at least 50mm 3 / kg, at least 75mm 3 / kg, at least 100mm3 / kg, at least 125mm 3 or at least 150mm 3 In certain embodiments, the total volume of bubbles per kilogram of glass is in the range of 1 to <1000 mm 3 / kg, for example, 1 to 950 mm 3 / kg, 2 to 900mm 3 / kg, 2 to 875mm 3 / kg, 5 to 850mm 3 / kg, 5 to 825mm 3 / kg, 10 to 800mm 3 / kg, 10 to 750mm 3 / kg, 25 to 500mm 3 / kg, 25 to 400mm 3 / kg, 25 to 400mm 3 / kg, 50 to 350mm 3 / kg, 50 to 300mm 3 / kg, 75 to 275mm 3 / kg, 75 to 250mm 3 / kg, 100 to 225mm 3 / kg, 100 to 200mm 3 / kg, 125 to 190mm 3 / kg, 125 to 180mm 3 / kg, 150 to 170mm 3 / kg, 150 to 160mm 3 / kg.

[0053] The production of pharmaceutical packaging often includes post-processing steps at high temperatures, such as forming pharmaceutical containers from glass tubes. A typical process for producing glass tubes for pharmaceutical containers involves forming a glass tube from a glass melt by stretching or other methods. The formed glass tube is then cut into larger sections with two open ends. During post-processing, one or both open ends may be closed, for example, by thermoforming, to provide pharmaceutical containers.

[0054] During these process steps, depending on the chloride content of the glass, chloride can evaporate from the glass and deposit on the inner surface of the glass tube of the pharmaceutical container, in particular forming a light ring. This light ring is detrimental to the optical impression of the resulting glass product and can spoil its visual appearance. A particular advantage of the glass according to any aspect of the invention is that it does not produce a light ring when processed into pharmaceutical containers.

[0055] The glass of the present invention comprises the following components in the following proportions (in wt %):

[0056] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0057] The proportion of SiO2 is in the range of 69.0 to 75.0 wt%, for example, 70.0 to 74.0 wt% or 71.0 to 73.0 wt%. The proportion of SiO2 is at least 69.0 wt%, for example, at least 70.0 wt% or at least 71.0 wt%. The proportion of SiO2 is at most 75.0 wt%, for example, at most 74.0 wt% or at most 73.0 wt%.

[0058] The proportion of B2O3 is in the range of 6.0 to 12.0 wt%, for example 8.0 to 12.0 wt% or 10.0 to 12.0 wt%. The proportion of B2O3 is at least 6.0 wt%, for example at least 8.0 wt% or at least 10.0 wt%. The proportion of B2O3 is at most 12.0 wt%.

[0059] The proportion of Al2O3 is in the range of 5.0 to 8.0 wt%, for example, >5.0 to 8.0 wt%, 5.5 to 8.0 wt%, 6.0 to 8.0 wt%, or 6.5 to 7.5 wt%. The proportion of Al2O3 can be, for example, at least 5.0 wt%, greater than 5.0 wt%, at least 5.5 wt%, at least 6.0 wt%, or at least 6.5 wt%. The proportion of Al2O3 can be at most 8.0 wt% or at most 7.5 wt%.

[0060] In certain embodiments, the weight ratio of the fraction of SiO2 to the fraction of Al2O3 is in the range of 8.5 to 12.0, for example, 9.0 to 11.5, 9.5 to 11.0, or 10.0 to 10.5. In certain embodiments, the weight ratio of the fraction of SiO2 to the fraction of Al2O3 is at least 8.5, at least 9.0, at least 9.5, or at least 10.0. In certain embodiments, the weight ratio of the fraction of SiO2 to the fraction of Al2O3 is at most 12.0, at most 11.5, at most 11.0, or at most 10.5.

[0061] The Na2O content is in the range of 5.0 to 9.0 wt%, for example, 6.0 to 8.5, 6.5 to 8.5, or 7.0 to 8.0 wt%. The Na2O content is at least 5.0 wt%, for example, at least 6.0 wt%, at least 6.5 wt%, at least 7.0 wt%, or greater than 7.0 wt%, such as at least 7.1 wt% or at least 7.2 wt%. The Na2O content is at most 9.0 wt%, for example, at most 8.5 wt% or at most 8.0 wt%.

[0062] In certain embodiments, the sum of the amounts of Na2O and Al2O3 is in the range of 12.5 to 16.5 wt%, for example, 12.75 to 16.25 wt%, 13.0 to 16.0 wt%, 13.25 to 15.75 wt%, 13.5 to 15.5 wt%, 13.75 to 15.25 wt%, or 14.0 to 15.0 wt%. In certain embodiments, the sum of the amounts of Na2O and Al2O3 is at least 12.5 wt%, at least 12.75 wt%, at least 13.0 wt%, at least 13.25 wt%, at least 13.5 wt%, at least 13.75 wt%, or at least 14.0 wt%. In certain embodiments, the sum of the proportions of Na2O and Al2O3 is at most 16.5 wt%, at most 16.25 wt%, at most 16.0 wt%, at most 15.75 wt%, at most 15.5 wt%, at most 15.25 wt% or at most 15.0 wt%.

[0063] The content of KO is in the range of 0 to 2.5 wt %, for example, 0.1 to 2.0 wt %, 0.2 to 1.5 wt %, or 0.5 to 1.0 wt %. In certain embodiments, the content of KO is at least 0.1 wt %, at least 0.2 wt %, or at least 0.5 wt %, for example, greater than 0.5 wt %, such as at least 0.6 wt %. The content of KO is at most 2.5 wt %, for example, at most 2.0 wt %, at most 1.5 wt %, or at most 1.0 wt %. Certain embodiments are free of KO.

[0064] In certain embodiments, the sum of the contents of Na2O and KO is in the range of 6.0 to 10.5 wt%, for example, 6.25 to 10.25 wt%, 6.5 to 10.0 wt%, 6.75 to 9.75 wt%, 7.0 to 9.5 wt%, 7.5 to 9.0 wt%, or 8.0 to 8.5 wt%. In certain embodiments, the sum of the contents of Na2O and KO is at least 6.0 wt%, at least 6.25 wt%, at least 6.5 wt%, at least 6.75 wt%, at least 7.0 wt%, at least 7.5 wt%, or at least 8.0 wt%, in particular greater than 8.0 wt%, such as at least 8.1 wt%. In certain embodiments, the sum of the contents of Na2O and KO is at most 10.5 wt%, at most 10.25 wt%, at most 10.0 wt%, at most 9.75 wt%, at most 9.5 wt%, at most 9.0 wt%, or at most 8.5 wt%.

[0065] The total amount of alkali metal oxides in the glass is referred to as RO. In certain embodiments, the proportion of RO is in the range of 6.0 to 10.5 wt%, for example, 6.25 to 10.25 wt%, 6.5 to 10.0 wt%, 6.75 to 9.75 wt%, 7.0 to 9.5 wt%, 7.2 to 9.3 wt%, 7.5 to 9.0 wt%, or 8.0 to 8.5 wt%. In certain embodiments, the proportion of RO is at least 6.0 wt%, at least 6.25 wt%, at least 6.5 wt%, at least 6.75 wt%, at least 7.0 wt%, at least 7.2 wt%, at least 7.5 wt%, or at least 8.0 wt%, in particular greater than 8.0 wt%, such as at least 8.1 wt%. In certain embodiments, the proportion of R2O is at most 10.5 wt%, at most 10.25 wt%, at most 10.0 wt%, at most 9.75 wt%, at most 9.5 wt%, at most 9.3 wt%, at most 9.0 wt% or at most 8.5 wt%.

[0066] In certain embodiments, the weight ratio of the fraction of SiO2 to the fraction of RO2 is in the range of 8.4 to 9.1, for example, 8.5 to 9.0, 8.6 to 8.9, or 8.7 to 8.8. In certain embodiments, the weight ratio of the fraction of SiO2 to the fraction of RO2 is at least 8.4, at least 8.5, at least 8.6, or at least 8.7. In certain embodiments, the weight ratio of the fraction of SiO2 to the fraction of RO2 is at most 9.1, at most 9.0, at most 8.9, or at most 8.8.

[0067] In certain embodiments, the weight ratio of the fraction of SiO2 to the fraction of Na2O is in the range of 8.5 to 10.5, for example, 8.75 to 10.25, 9.0 to 10.0, or 9.25 to 9.75. In certain embodiments, the weight ratio of the fraction of SiO2 to the fraction of Na2O is at least 8.5, at least 8.75, at least 9.0, or at least 9.25. In certain embodiments, the weight ratio of the fraction of SiO2 to the fraction of Na2O is at most 10.5, at most 10.25, at most 10.0, or at most 9.75.

[0068] The content of CaO is in the range of 0 to 2.0 wt%, for example, 0.1 to 1.5 wt%, 0.2 to 1.0 wt%, or 0.4 to 0.8 wt%. In certain embodiments, the content of CaO is at least 0.1 wt%, at least 0.2 wt%, or at least 0.4 wt%, for example, at least 0.5 wt%. The content of CaO is at most 2.0 wt%, at most 1.5 wt%, at most 1.0 wt%, or at most 0.8 wt%, such as at most 0.7 wt% or less than 0.6 wt%. Certain embodiments are free of CaO.

[0069] When it is stated in this disclosure that a glass is free of a certain component or that the glass contains no certain component, this means that the component is present in the glass only as an impurity. This means that it is not added in significant amounts. "Not in significant amounts" means an amount of less than 500 ppm (by weight), preferably less than 400 ppm (by weight), more preferably less than 300 ppm (by weight), more preferably less than 200 ppm (by weight), more preferably less than 100 ppm (by weight), particularly preferably less than 50 ppm (by weight), and most preferably less than 10 ppm (by weight). Preferably, the glass of the present invention is free of Li2O, MgO, BaO, SrO, Fe2O3, TiO2, ZrO2, As2O3, Sb2O3, MnO, ZnO, PbO, Rb2O, PO5, SO3, Pb, Cr, and / or Cd.

[0070] In view of the toxicity of As2O3 and Sb2O3, the glass according to the present invention is particularly free of these two substances.

[0071] In particular, the glass according to the invention does not contain MgO, BaO and / or SrO. In particular, the glass according to the invention is free of BaO.

[0072] In particular, the glass according to the invention does not contain those components which are not mentioned in this disclosure.

[0073] The Cl content in the glasses of the present invention can be in the range of 75 ppm (by weight) to 800 ppm (by weight), for example, 100 to 700 ppm, 125 to 600 ppm, 150 to 500 ppm, 175 to 400 ppm, or 200 to 300 ppm. The Cl content can be at least 75 ppm, for example, at least 100 ppm, at least 125 ppm, at least 150 ppm, at least 175 ppm, or at least 200 ppm. The Cl content can be up to 800 ppm, for example, up to 700 ppm, up to 600 ppm, up to 500 ppm, up to 400 ppm, or up to 300 ppm. Cl is a very effective refining agent for removing bubbles. However, high Cl content can lead to light rings, particularly in the manufacture of pharmaceutical containers, thereby impairing their visual appearance.

[0074] The content of CeO2 in the glasses according to the invention may be in the range of 10 ppm (by weight) to <2000 ppm (by weight), for example, 100 to 1900 ppm, 250 to 1800 ppm, 500 to 1700 ppm, 750 to 1600 ppm, 800 to 1500 ppm, 850 to 1450 ppm, 900 to 1400 ppm, 950 to 1350 ppm, 1000 to 1300 ppm, or 1050 to 1250 ppm. The content of CeO2 may be at least 10 ppm, for example, at least 100 ppm, at least 250 ppm, at least 500 ppm, at least 750 ppm, at least 800 ppm, at least 850 ppm, at least 900 ppm, at least 950 ppm, at least 1000 ppm, or at least 1050 ppm. The CeO2 content can be less than 2000 ppm, for example, up to 1900 ppm, up to 1800 ppm, up to 1700 ppm, up to 1600 ppm, up to 1500 ppm, up to 1450 ppm, up to 1400 ppm, up to 1350 ppm, up to 1300 ppm, or up to 1250 ppm. CeO2 is a very effective refining agent for removing bubbles. However, high CeO2 contents can shift the color impression of the glass to an undesirable yellow tint.

[0075] The sum of the Cl and CeO portions can be at least 800 ppm (by weight), for example, at least 900 ppm, at least 950 ppm, at least 1000 ppm, at least 1050 ppm, or at least 1100 ppm. Based on such amounts, a particularly low number of bubbles can be achieved. In certain embodiments, the sum of the Cl and CeO portions is in the range of 800 to 2000 ppm, for example, 900 to 1900 ppm, 950 to 1800 ppm, 1000 to 1700 ppm, 1050 to 1600 ppm, or 1100 to 1500 ppm. In certain embodiments, the sum of the Cl and CeO portions is at most 2000 ppm, at most 1900 ppm, at most 1800 ppm, at most 1700 ppm, at most 1600 ppm, or at most 1500 ppm.

[0076] The weight ratio of the CeO2 content to the Cl content can be at most 10.0, for example, at most 9.0, at most 8.0, at most 7.0, at most 6.0, or at most 5.0. This ratio results in a particularly favorable color position. In certain embodiments, the weight ratio of the CeO2 content to the Cl content is in the range of 0.1 to 10.0, for example, 0.2 to 9.0, 0.5 to 8.0, 1.0 to 7.0, 1.5 to 6.0, or 2.0 to 5.0. In certain embodiments, the weight ratio of the CeO2 content to the Cl content is at least 0.1, at least 0.2, at least 0.5, at least 1.0, at least 1.5, or at least 2.0.

[0077] The glasses of the present invention may optionally include F. In certain embodiments, the F content ranges from 0 to 1.0 wt%, for example, from 10 ppm to 5000 ppm, from 20 ppm to 2500 ppm, from 50 ppm to 1000 ppm, or from 100 ppm to 500 ppm. In certain embodiments, the F content is at least 10 ppm, at least 20 ppm, at least 50 ppm, or at least 100 ppm. In certain embodiments, the F content is at most 1.0 wt%, for example, at most 5000 ppm, at most 2500 ppm, at most 1000 ppm, or at most 500 ppm. Some embodiments are free of F.

[0078] The glasses of the present invention may optionally include SnO2. In certain embodiments, the SnO2 content ranges from 0 to 1200 ppm, for example, from 10 to 1000 ppm, from 20 to 500 ppm, or from 50 to 250 ppm. In certain embodiments, the SnO2 content is at least 10 ppm, at least 20 ppm, or at least 50 ppm. In certain embodiments, the SnO2 content is at most 1200 ppm, at most 1000 ppm, at most 500 ppm, or at most 250 ppm. Some embodiments are free of SnO2.

[0079] The glass of the present invention has excellent hydrolytic resistance. In particular, the glass has Class I hydrolytic resistance (HGA1 according to ISO 720:2020(E) or Type I according to USP 660 / Glass Grains). The high hydrolytic resistance of the glass of the present invention is particularly advantageous for use in pharmaceutical packaging.

[0080] The HGA1 limit of ISO 720:2020(E) corresponds to 62 μg of Na2O equivalent per gram of glass granules. This means that, in the test of ISO 720:2020(E), glasses having an alkali equivalent expressed as the mass of sodium oxide (Na2O) per gram of glass granules up to and including 62 μg / g are classified as HGA1. The term "HGA" stands for the hydrolysis resistance of glass granules as determined by the autoclave method.

[0081] The glasses of the present invention exhibit excellent hydrolytic resistance, even significantly exceeding the HGA1 limit. This means that, in the ISO 720:2020(E) test, the corresponding Na2O equivalent of the glasses of the present invention is significantly lower than 62 μg of Na2O per gram of glass particles. This can be expressed as a percentage of the HGA1 limit. For example, 62 μg of Na2O per gram of glass particles corresponds to 100% of the HGA1 limit. Similarly, a result of 46.5 μg of Na2O per gram of glass particles in the ISO 720:2020(E) test corresponds to 75% of the HGA1 limit. It is noteworthy that the lower the percentage of the HGA1 limit, the better the hydrolytic resistance of the glass.

[0082] In certain embodiments, the glass of the present invention has a hydrolytic resistance corresponding to less than 75% of the HGA1 limit according to ISO 720:2020(E), for example, at most 74%, at most 73%, at most 72%, at most 71%, at most 70%, at most 69%, at most 68%, at most 67%, at most 66%, at most 65%, at most 62%, at most 60%, at most 55%, at most 50%, at most 45%, at most 40%, or at most 39%. The hydrolytic resistance of the glass of the present invention can correspond, for example, to at least 5%, at least 10%, at least 15%, at least 20%, at least 25%, or at least 30% of the HGA1 limit according to ISO 720:2020(E). The hydrolysis resistance of the glasses according to the invention can correspond, for example, to 5% to 75% of the HGA1 limit according to ISO 720:2020(E), for example, 5% to 74%, 5% to 73%, 10% to 72%, 10% to 71%, 10% to 70%, 15% to 69%, 15% to 68%, 15% to 67%, 20% to 66%, 20% to 65%, 20% to 62%, 25% to 60%, 25% to 55%, 25% to 50%, 30% to 45%, 30% to 40% or 30% to 39%.

[0083] Preferably, the acid resistance of the glass according to the invention corresponds to class S3 or better, more preferably S2 or better, more preferably S1 according to DIN 12116:2001-03.

[0084] Preferably, the alkali resistance of the glass according to the invention corresponds to class A2 or better, more preferably class A1 according to ISO 695:1991 (E).

[0085] The glass of the present invention may be in any form. For example, the glass of the present invention may be a glass container, a glass sheet, a glass plate, a glass rod, a glass tube, a glass block, or other articles, such as articles useful in the pharmaceutical or medical fields.

[0086] In certain embodiments, the glasses of the present invention have a thickness of 0.10 to 5.00 mm, such as 0.10 to 3.00 mm, 0.15 to 3.00 mm, 0.20 to 2.75 mm, 0.25 to 2.50 mm, 0.30 to 2.25 mm, 0.35 to 2.00 mm, 0.40 to 1.75 mm, or 0.45 to 1.50 mm. In certain embodiments, for example, the thickness can be at least 0.10 mm, at least 0.15 mm, at least 0.15 mm, at least 0.20 mm, at least 0.25 mm, at least 0.30 mm, at least 0.35 mm, at least 0.40 mm, or at least 0.45 mm. In certain embodiments, for example, the thickness can be at most 5.00 mm, at most 3.00 mm, at most 2.75 mm, at most 2.50 mm, at most 2.25 mm, at most 2.00 mm, at most 1.75 mm, or at most 1.50 mm.

[0087] In certain embodiments, the glass of the present invention is a glass tube, particularly a glass tube or pharmaceutical container having a wall thickness between 0.10 and 5.00 mm, such as 0.10 to 3.00 mm, 0.15 to 3.00 mm, 0.20 to 2.75 mm, 0.25 to 2.50 mm, 0.30 to 2.25 mm, 0.35 to 2.00 mm, 0.40 to 1.75 mm, or 0.45 to 1.50 mm. In certain embodiments, for example, the wall thickness can be at least 0.10 mm, at least 0.15 mm, at least 0.15 mm, at least 0.20 mm, at least 0.25 mm, at least 0.30 mm, at least 0.35 mm, at least 0.40 mm, or at least 0.45 mm. In certain embodiments, the wall thickness may be at most 5.00 mm, at most 3.00 mm, at most 2.75 mm, at most 2.50 mm, at most 2.25 mm, at most 2.00 mm, at most 1.75 mm, or at most 1.50 mm.

[0088] The present invention also relates to a method for producing glass according to any aspect of the present invention. The method particularly comprises the steps of melting glass raw materials and cooling the resulting glass. The method particularly comprises the step of processing the glass melt by a down-draw method, an overflow melting method, a redraw method, a float method, a rod drawing method, or a tube drawing method, particularly a Danner method, a Velotin method, or a vertical down-draw method. In certain embodiments, the method comprises the step of processing the glass melt by a tube drawing method, particularly a Danner method, a Velotin method, or a vertical down-draw method.

[0089] The present invention also relates to the use of the glass according to any aspect of the present invention as a pharmaceutical container.

[0090] The present invention also relates to a pharmaceutical container comprising the glass according to any aspect of the present invention.

[0091] The pharmaceutical container can be selected from bottles, for example large bottles or small bottles, such as injection bottles or vials, ampoules, cartridges, bottles, flasks, vials, beakers or syringes. The term "pharmaceutical container" is understood to mean a package made of glass that is in direct contact with the drug. The package protects the drug from environmental influences and maintains the specifications of the drug before use by the patient.

[0092] The glass according to the invention may also be an intermediate product for the production of another glass article, such as tubular glass in the form of a semi-finished product, for example for further processing into pharmaceutical containers.

[0093] The present invention also relates to a glass article comprising or consisting of the glass of the present invention. In certain embodiments, the glass article is a vial, an ampoule, a cartridge, a syringe, a rod, a tube, or a sheet. The glass article may also be glass cullet.

[0094] Exemplary embodiments

[0095] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0096] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0097] wherein the Cl content is in the range of 75 ppm (by weight) to 800 ppm (by weight), wherein the CeO2 content is in the range of 10 ppm (by weight) to <2000 ppm (by weight), the sum of the Cl and CeO2 contents is at least 800 ppm (by weight), the weight ratio of the CeO2 content to the Cl content is at most 10, and wherein the glass has a color position in the CIE 1931 color space such that, with a sample thickness of 25 mm and using an illuminant "D65" at 6500 K for a CIE standard observer within a 2° arc of the fovea, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.60.

[0098] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0099]

[0100]

[0101] wherein the Cl content is in the range of 75 ppm (by weight) to 800 ppm (by weight), wherein the CeO2 content is in the range of 10 ppm (by weight) to <2000 ppm (by weight), the sum of the Cl and CeO2 content is at least 800 ppm (by weight), the weight ratio of the CeO2 content to the Cl content is at most 10, and wherein the glass shows a bubble count of less than 1000 bubbles / cm3 in a melt termination test (MTT test) 2 .

[0102] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0103] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0104] wherein the Cl content is in the range of 75 ppm (by weight) to 800 ppm (by weight), wherein the CeO2 content is in the range of 10 ppm (by weight) to <2000 ppm (by weight), the sum of the Cl and CeO2 content is at least 800 ppm (by weight), the weight ratio of the CeO2 content to the Cl content is at most 10, and wherein the total bubble volume per kg of glass is less than 1000 mm 3 / kg.

[0105] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0106]

[0107]

[0108] wherein the Cl content is in the range of 75 ppm (by weight) to 800 ppm (by weight), wherein the CeO2 content is in the range of 10 ppm (by weight) to <2000 ppm (by weight), the sum of the Cl and CeO2 contents is at least 800 ppm (by weight), the weight ratio of the CeO2 content to the Cl content is at most 10, and wherein the hydrolysis resistance of the glass corresponds to less than 75% of the HGA1 limit according to ISO 720:2020 (E).

[0109] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0110] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0111] The glass has a color position in the CIE 1931 color space such that, with a sample thickness of 25 mm and using an illuminant "D65" at 6500 K for a CIE standard observer within 2° of arc from the fovea, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.60, and the glass exhibits a bubble count of less than 1000 bubbles / cm in a melt termination test (MTT test). 2 .

[0112] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0113] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0114] wherein the glass has a color position in the CIE 1931 color space such that, for a sample thickness of 25 mm, using illuminant "D65" at 6500 K, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.60 within 2° of the fovea for a CIE standard observer, and wherein the total volume of bubbles per kilogram of glass is less than 1000 mm 3 / kg.

[0115] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0116] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0117] The glass has a color position in the CIE 1931 color space such that, with a sample thickness of 25 mm and using an illuminant "D65" at 6500 K for a CIE standard observer within 2° arc of the fovea, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.60, and the hydrolysis resistance of the glass corresponds to less than 75% of the HGA1 limit specified in ISO 720:2020(E).

[0118] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0119] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0120] The total volume of bubbles per kilogram of glass is less than 1000mm3 / kg, and wherein the glass shows a bubble count of less than 1000 bubbles / cm in a melt termination test (MTT-test) 2 .

[0121] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0122] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0123] The glass shows less than 1000 bubbles / cm in the melt termination test (MTT test) 2 , and wherein the hydrolytic resistance of the glass corresponds to less than 75% of the HGA1 limit specified in ISO 720:2020(E).

[0124] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0125] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0126] The total volume of bubbles per kilogram of glass is less than 1000mm 3 / kg, and wherein the hydrolytic resistance of the glass corresponds to less than 75% of the HGA1 limit specified in ISO 720:2020(E).

[0127] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0128]

[0129]

[0130] wherein the proportion of Cl is in the range of 75 ppm (by weight) to 800 ppm (by weight), wherein the proportion of CeO2 is in the range of 10 ppm (by weight) to <2000 ppm (by weight), the sum of the proportions of Cl and CeO2 is at least 800 ppm (by weight), the weight ratio of the proportion of CeO2 to the proportion of Cl is at most 10, wherein the glass has a color position in the CIE 1931 color space such that with a sample thickness of 25 mm, using an illuminant "D65" at 6500 K for a CIE standard observer within 2° of the fovea, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.60, and wherein the glass shows a bubble count of less than 1000 bubbles / cm2 in a melt termination test (MTT test). 2 .

[0131] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0132] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0133] wherein the Cl content is in the range of 75 ppm (by weight) to 800 ppm (by weight), wherein the CeO2 content is in the range of 10 ppm (by weight) to <2000 ppm (by weight), the sum of the Cl and CeO2 contents is at least 800 ppm (by weight), the weight ratio of the CeO2 content to the Cl content is at most 10, wherein the glass has a color position in the CIE 1931 color space such that, with a sample thickness of 25 mm and using an illuminant "D65" at 6500 K for a CIE standard observer within 2° of the fovea, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.60, and wherein the total volume of bubbles per kg of glass is less than 1000 mm 3 / kg.

[0134] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0135] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0136] wherein the Cl content is in the range of 75 ppm (by weight) to 800 ppm (by weight), wherein the CeO2 content is in the range of 10 ppm (by weight) to <2000 ppm (by weight), the sum of the Cl and CeO2 contents is at least 800 ppm (by weight), the weight ratio of the CeO2 content to the Cl content is at most 10, the glass has a color position in the CIE 1931 color space such that, with a sample thickness of 25 mm and using an illuminant "D65" at 6500 K for a CIE standard observer within a 2° arc of the fovea, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.60, and wherein the hydrolysis resistance of the glass corresponds to less than 75% of the HGA1 limit specified in ISO 720:2020 (E).

[0137] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0138] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0139] wherein the Cl content is in the range of 75 ppm (by weight) to 800 ppm (by weight), wherein the CeO2 content is in the range of 10 ppm (by weight) to <2000 ppm (by weight), the sum of the Cl and CeO2 content is at least 800 ppm (by weight), the weight ratio of the CeO2 content to the Cl content is at most 10, wherein the total bubble volume per kg of glass is less than 1000 mm 3 / kg, and wherein the glass shows a bubble count of less than 1000 bubbles / cm in a melt termination test (MTT-test) 2 .

[0140] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0141] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0142] wherein the Cl content is in the range of 75 ppm (by weight) to 800 ppm (by weight), wherein the CeO2 content is in the range of 10 ppm (by weight) to <2000 ppm (by weight), the sum of the Cl and CeO2 contents is at least 800 ppm (by weight), the weight ratio of the CeO2 content to the Cl content is at most 10, wherein the glass shows a bubble count of less than 1000 bubbles / cm3 in a melt termination test (MTT test) 2 , and wherein the hydrolytic resistance of the glass corresponds to less than 75% of the HGA1 limit specified in ISO 720:2020(E).

[0143] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0144] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-750 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0145] wherein the Cl content is in the range of 75 ppm (by weight) to 800 ppm (by weight), wherein the CeO2 content is in the range of 10 ppm (by weight) to <2000 ppm (by weight), the sum of the Cl and CeO2 content is at least 800 ppm (by weight), the weight ratio of the CeO2 content to the Cl content is at most 10, wherein the total bubble volume per kg of glass is less than 1000 mm 3 / kg, and wherein the hydrolysis resistance of the glass corresponds to less than 75% of the HGA1 limit specified in ISO 720:2020(E).

[0146] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0147] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0148] wherein the glass has a color position in the CIE 1931 color space such that, for a sample thickness of 25 mm, using illuminant "D65" at 6500 K, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.60 within 2° of the fovea for a CIE standard observer, wherein the total volume of bubbles per kilogram of glass is less than 1000 mm 3 / kg, and wherein the glass shows a bubble count of less than 1000 bubbles / cm in a melt termination test (MTT-test) 2 .

[0149] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0150] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0151] wherein the glass has a color position in the CIE 1931 color space such that, with a sample thickness of 25 mm and using an illuminant "D65" at 6500 K for a CIE standard observer within 2° of arc from the fovea, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.60, wherein the glass exhibits a bubble count of less than 1000 bubbles / cm in a melt termination test (MTT test) 2 , and wherein the hydrolytic resistance of the glass corresponds to less than 75% of the HGA1 limit specified in ISO 720:2020(E).

[0152] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0153] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0154] wherein the glass has a color position in the CIE 1931 color space such that, for a sample thickness of 25 mm, using illuminant "D65" at 6500 K, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.60 within 2° of the fovea for a CIE standard observer, wherein the total volume of bubbles per kilogram of glass is less than 1000 mm 3 / kg, and wherein the hydrolytic resistance of the glass corresponds to less than 75% of the HGA1 limit specified in ISO 720:2020(E).

[0155] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0156] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0157] The total volume of bubbles per kilogram of glass is less than 1000mm 3 / kg, wherein the glass shows a bubble count of less than 1000 bubbles / cm in the melt termination test (MTT test) 2 , and wherein the hydrolytic resistance of the glass corresponds to less than 75% of the HGA1 limit specified in ISO 720:2020(E).

[0158] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0159] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0160] wherein the Cl content is in the range of 75 ppm (by weight) to 800 ppm (by weight), wherein the CeO2 content is in the range of 10 ppm (by weight) to <2000 ppm (by weight), the sum of the Cl and CeO2 contents is at least 800 ppm (by weight), the weight ratio of the CeO2 content to the Cl content is at most 10, wherein the glass has a color position in the CIE 1931 color space such that, with a sample thickness of 25 mm and using an illuminant "D65" at 6500 K for a CIE standard observer within 2° of the fovea, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.60, wherein the total volume of bubbles per kg of glass is less than 1000 mm 3 / kg, and wherein the glass shows a bubble count of less than 1000 bubbles / cm in a melt termination test (MTT-test) 2 .

[0161] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0162] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0163] wherein the proportion of Cl is in the range of 75 ppm (by weight) to 800 ppm (by weight), wherein the proportion of CeO2 is in the range of 10 ppm (by weight) to <2000 ppm (by weight), the sum of the proportions of Cl and CeO2 is at least 800 ppm (by weight), and the weight ratio of the proportion of CeO2 to the proportion of Cl is at most 10, wherein the glass has a color position in the CIE 1931 color space such that, with a sample thickness of 25 mm and using an illuminant "D65" at 6500 K for a CIE standard observer within a range of 2° arc of the fovea, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.60, wherein the glass shows a bubble count of less than 1000 bubbles / cm2 in a melting termination test (MTT test). 2 , and wherein the hydrolytic resistance of the glass corresponds to less than 75% of the HGA1 limit specified in ISO 720:2020(E).

[0164] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0165] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0166] wherein the Cl content is in the range of 75 ppm (by weight) to 800 ppm (by weight), wherein the CeO2 content is in the range of 10 ppm (by weight) to <2000 ppm (by weight), the sum of the Cl and CeO2 contents is at least 800 ppm (by weight), the weight ratio of the CeO2 content to the Cl content is at most 10, wherein the glass has a color position in the CIE 1931 color space such that, with a sample thickness of 25 mm and using an illuminant "D65" at 6500 K for a CIE standard observer within 2° of the fovea, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.60, wherein the total volume of bubbles per kg of glass is less than 1000 mm 3 / kg, and wherein the hydrolysis resistance of the glass corresponds to less than 75% of the HGA1 limit specified in ISO 720:2020(E).

[0167] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0168]

[0169]

[0170] wherein the Cl content is in the range of 75 ppm (by weight) to 800 ppm (by weight), wherein the CeO2 content is in the range of 10 ppm (by weight) to <2000 ppm (by weight), the sum of the Cl and CeO2 content is at least 800 ppm (by weight), the weight ratio of the CeO2 content to the Cl content is at most 10, wherein the total bubble volume per kg of glass is less than 1000 mm 3 / kg, wherein the glass shows a bubble count of less than 1000 bubbles / cm in the melt termination test (MTT test) 2 , and wherein the hydrolytic resistance of the glass corresponds to less than 75% of the HGA1 limit specified in ISO 720:2020(E).

[0171] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0172] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0173] wherein the glass has a color position in the CIE 1931 color space such that, for a sample thickness of 25 mm, using illuminant "D65" at 6500 K, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.60 within 2° of the fovea for a CIE standard observer, wherein the total volume of bubbles per kilogram of glass is less than 1000 mm 3 / kg, wherein the glass shows a bubble count of less than 1000 bubbles / cm in the melt termination test (MTT test) 2 , and wherein the hydrolytic resistance of the glass corresponds to less than 75% of the HGA1 limit specified in ISO 720:2020(E).

[0174] In certain embodiments, the present invention relates to a glass comprising the following components in the following specified proportions (in wt %):

[0175] Components Share (in wt%) <![CDATA[SiO2]]> 69.0-75.0 <![CDATA[B2O3]]> 6.0-12.0 <![CDATA[Al2O3]]> 5.0-8.0 <![CDATA[Na2O]]> 5.0-9.0 <![CDATA[K2O]]> 0-2.5 CaO 0-2.0

[0176] wherein the proportion of Cl is in the range of 75 ppm (by weight) to 800 ppm (by weight), wherein the proportion of CeO2 is in the range of 10 ppm (by weight) to <2000 ppm (by weight), the sum of the proportions of Cl and CeO2 is at least 800 ppm (by weight), and the weight ratio of the proportion of CeO2 to the proportion of Cl is at most 10, wherein the glass has a color position in the CIE 1931 color space such that, with a sample thickness of 25 mm and using an illuminant "D65" at 6500 K for a CIE standard observer within a range of 2° arc of the fovea, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.60, wherein the glass shows a bubble count of less than 1000 bubbles / cm2 in a melting termination test (MTT test). 2 , where the total volume of bubbles per kilogram of glass is less than 1000mm 3 / kg, and wherein the hydrolytic resistance of the glass corresponds to less than 75% of the HGA1 limit specified in ISO 720:2020(E). BRIEF DESCRIPTION OF THE DRAWINGS

[0177] Figure 1 Shows the melting termination test (MTT test) per cm 2 The relationship between the number of bubbles (y-axis) and the sum of the fractions of Cl and CeO2 (x-axis). The data points correspond to Examples 1 and 3 to 8. The dotted line represents an exponential fit performed using Excel software. DETAILED DESCRIPTION

[0178] The present invention is further described by the following examples.

[0179] 1. Glass composition

[0180] The compositions of the following examples are provided, analyzed in wt %.

[0181] Table 1

[0182]

[0183]

[0184] The glasses of these two examples also contain small amounts of impurities of Fe2O3, TiO2 and ZrO2, the respective proportions being in the range of 160 to 220 ppm (by weight).

[0185] The analyzed glass compositions are shown in Table 1. The proportions of F, Cl, and CeO2 in the synthesized composition are as follows (in wt%):

[0186] Table 2

[0187] Components Example 1 Example 2 F 0.04 - Cl 0.03 0.03 <![CDATA[CeO2]]> 0.12 0.12

[0188] Based on the glass compositions of Examples 1 and 2 shown in Tables 1 and 2 above, the proportions of F, Cl, and CeO2 in the synthetic compositions for obtaining Examples 3 to 9 were varied as follows (in wt%):

[0189] Table 3

[0190] Components Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 F 0.04 0.04 - 0.04 0.04 0.04 0.04 Cl 0.06 0.06 0.06 0.03 - 0.06 0.22 <![CDATA[CeO2]]> 0.08 0.1 0.1 0.1 0.1 0.05 -

[0191] 2. Refining Test

[0192] The refining properties (refinability) were tested for Example 1 and Examples 3 to 9. These properties were evaluated using the so-called Melt Termination Test (MTT Test).

[0193] The synthetic composition (glass raw material mixture) of each example was placed in a separate crucible. The crucible was placed in a furnace preheated to 1450°C and held there for one hour. The furnace was then heated to 1600°C at a heating rate of 200 K / h and held at this temperature for 15 minutes.

[0194] According to the procedure shown, the glass raw material mixture is completely melted without any residue and subjected to preliminary refining. However, the refining is not complete.

[0195] Afterwards (after holding the furnace at 1600°C for 15 minutes), the crucible is removed and placed on a refractory surface. The molten glass cools rapidly within the crucible, essentially being "frozen" in a state that provides information about the refining results.

[0196] This method essentially allows for premature refining, leaving a readily detectable number of bubbles in the glass, even when a combination of refining agents is used that removes more or less all bubbles after refining is complete. Therefore, this test is more sensitive than a test performed after refining is complete when comparing the effects of different refining agents.

[0197] After the glass had completely cooled, a cylindrical sample was taken from each example for analysis of the proportions of F, Cl and CeO 2 in the glass and the number of bubbles.

[0198] The analysis of the proportions of F, Cl and CeO2 in the glass composition was carried out on slices cut from cylindrical samples.

[0199] When analyzing the number of bubbles, the cylindrical sample was sawn in half and the vertical sawn surface of one of the resulting half cylinders was polished for further analysis of the number of bubbles in the glass.

[0200] The number of bubbles was determined by visual inspection of an area of ​​1 cm x 1 cm located in the center of the polished saw face at a depth of 2.5 cm (the depth of a semi-cylinder of glass). The sample was prepared so that the area represented by the saw face was located 1 cm below the surface of the glass melt in the crucible.

[0201] The number of bubbles in a 1 cm x 1 cm area within a depth of 2.5 cm is expressed as bubbles per square centimeter. The corresponding volume is approximately 2.5 cm 3 , but not exactly 2.5cm 3 The reason is that the depth of 2.5 cm is the depth of the half cylinder. This is the maximum depth of the sample. The sample depth at the edge of the sample is slightly less, only about 2.4 cm. However, the sample volume is approximately 2.5 cm. 3 Therefore, according to the MTT test, the number of bubbles per square centimeter is roughly equivalent to the number of bubbles per 2.5 cm 3 For example, 50 bubbles per square centimeter is roughly equivalent to 2.5 cm 3 There are 50 bubbles, or about 20 bubbles per cubic centimeter.

[0202] The results are summarized in the table below and the proportions of F, Cl and CeO 2 (in wt %) determined by analysis of the individual samples are indicated.

[0203] Table 4

[0204] Example No. Cl F <![CDATA[CeO2]]> <![CDATA[Number of bubbles / cm 2 > Example 1 0.033 0.034 0.12 ～10 Example 3 0.039 0.034 0.079 ～<10 Example 3 (repeated) 0.038 0.035 0.096 ～20 Example 4 0.044 0.033 0.094 ～<50 Example 4 (repeated) 0.038 0.035 0.096 ～20 Example 5 0.037 - 0.094 ～50 Example 6 0.025 0.04 0.09 ～150-200 Example 7 - 0.029 0.098 ～500 Example 8 0.031 0.029 0.046 ～1000 Example 9 0.107 0.038 - ～50 Example 9 (repeat 1) 0.106 0.045 - ～50 Example 9 (repeat 2) 0.094 0.037 - ～50

[0205] “~” in Table 4 indicates the approximate number of bubbles.

[0206] Repeated experiments on Examples 3, 4 and 9 showed a high degree of reproducibility of the results, both with regard to the glass composition and the number of bubbles.

[0207] Example 5 confirms the conclusion that F is an optional component. Good results can be obtained with or without F.

[0208] In contrast, both Cl and CeO2 are necessary to obtain excellent results. Example 7 shows that even though reasonable amounts of F and CeO2 have been used, the number of bubbles is still quite high (about 500) in the absence of Cl.

[0209] Although low bubble counts can be achieved without CeO2 (Example 9), this requires a relatively high proportion of Cl, which can lead to light rings during post-processing including hot forming.

[0210] In the case of a low total content of Cl and CeO 2 , the number of bubbles is relatively high (Example 8). In fact, the number of bubbles is even higher than in the case of no Cl (Example 7).

[0211] The results of the examples (Example 1 and Examples 3-8) containing CeO2 are as follows Figure 1 shown.

[0212] 3. Completely refined

[0213] To evaluate the effectiveness of the refining agent combination of the present invention, full refining tests were conducted on Examples 1, 2, and 9. In the full refining tests, melting and refining were not stopped after 15 minutes, as in the MTT test described above. Instead, the refining process continued for several hours. The refined glass melt was then poured from the crucible into a mold and slowly cooled in a cooling furnace.

[0214] The results are summarized in the following table:

[0215] Example No. Cl F <![CDATA[CeO2]]> bubble Example 1 0.025 0.031 0.112 No bubbles Example 2 0.026 - 0.12 No bubbles Example 9 0.10 0.03 - No bubbles

[0216] All examples were free of bubbles.

[0217] 4. Color Position

[0218] Examples 1 and 9 were tested for their positions in the CIE 1931 color space using illuminant D65 at 6500K and a CIE 1931 2° standard observer.

[0219] We analyzed the glass's transmittance. Based on the results, we determined extinction curves, which we used to calculate the color positions for thicknesses of 25mm, 750mm, and 1500mm when illuminated with light source D65. The results are shown in the table below.

[0220] Example No. Thickness [mm] x value y value Example 1 25 0.3152 0.3330 Example 1 750 0.3723 0.4178 Example 1 1500 0.4128 0.4643 Example 9 25 0.3138 0.3312 Example 9 750 0.3376 0.3852 Example 9 1500 0.3566 0.4312

[0221] At a thickness of 25 mm, the color positions are essentially the same for Example 1 and Example 9. For the thicker sample, the x and y values ​​are higher for Example 1 compared to Example 9. However, the color positions are still within the desired range.

[0222] 5. Hydrolysis resistance

[0223] The hydrolysis resistance test was carried out according to ISO 720:2020(E) for Examples 1 and 2. The results are given in the table below as alkali equivalent (μg) of Na2O per gram of glass particles and as a percentage of the HGA1 limit.

[0224]

[0225] The glass of the present invention has excellent hydrolysis resistance.

Claims

1. A glass comprising the following components in the following proportions, calculated in wt %: The Cl content is in the range of 75 ppm to 800 ppm by weight, the CeO2 content is in the range of 10 ppm to <2000 ppm by weight, the sum of the Cl and CeO2 contents is at least 800 ppm by weight, and the weight ratio of the CeO2 content to the Cl content is at most 10.

2. The glass of claim 1 , wherein the glass has a color position in the CIE 1931 color space such that, with a sample thickness of 25 mm and using an illuminant "D65" at 6500 K for a CIE standard observer within 2° of arc of the fovea, the x value is at least 0.20 and at most 0.50, and the y value is at least 0.20 and at most 0.

60.

3. The glass according to any one of the preceding claims, wherein the total volume of bubbles per kilogram of glass is less than 1000 mm 3 / kg, wherein the glass shows a bubble count of less than 1000 bubbles / cm in a melt termination test, MTT test 2 , and / or wherein the hydrolysis resistance of the glass corresponds to less than 75% of the HGA1 limit specified in ISO 720:2020(E).

4. The glass according to claim 1, wherein the weight ratio of the fraction of SiO2 to the fraction of Al2O3 is in the range of 8.5 to 12.

0.

5. The glass according to claim 1, wherein the sum of the proportions of Na2O and K2O is in the range of 6.0 to 10.5 wt.%.

6. The glass according to any one of claims 2 to 5, wherein the ratio of the y value to the x value is in the range of 1.01 to 1.10 when the sample thickness is 25 mm.

7. The glass according to any one of claims 2 to 6, wherein the difference between the y value when the sample thickness is 750 mm and the y value when the sample thickness is 25 mm is in the range of 0.01 to 0.

15.

8. The glass according to any one of the preceding claims, wherein the glass is free of As2O3, Sb2O3 and BaO.

9. The glass according to claim 1, wherein the sum of the fractions of Cl and CeO2 is at most 2000 ppm by weight.

10. The glass according to claim 1, wherein the weight ratio of the fraction of CeO2 to the fraction of Cl is at least 0.

1.

11. The glass according to claim 1, wherein the weight ratio of the fraction of SiO2 to the fraction of R2O is at most 9.

1.

12. The glass according to claim 1, wherein the weight ratio of the fraction of SiO2 to the fraction of Na2O is at most 10.

5.

13. The glass according to claim 1, wherein the sum of the proportions of Na2O and Al2O3 is at least 13.5 wt.-%.

14. A method for producing glass according to any one of the preceding claims, comprising the step of processing the glass melt by a down-draw process, an overflow fusion process, a redraw process, a float process, a rod drawing process or a tube drawing process, in particular a Danner process or a Velotin process or a vertical down-draw process.

15. A glass article comprising or consisting of the glass according to any one of claims 1 to 13, wherein the glass article is selected from the group consisting of a vial, an ampoule, a cartridge, a syringe, a rod, a tube, crushed material, and a sheet.

16. Use of the glass according to any one of claims 1 to 13 as a pharmaceutical container.

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