glass tube

Abstract

To provide a glass tube, especially to provide a glass tube for easily producing a container for storing a high-quality pharmaceutical composition, a method for producing the same, and its use.SOLUTION: A glass tube has a relative cross-sectional area deviation defined by the following expression, where the following expression holds, where QFmax is the maximum cross-sectional area of at least two cross-sections of this tube, QFmin is the minimum cross-sectional area of the same cross-section, the cross-sections are spaced apart from each other along the length of the glass tube, k is 0.0023 m-1, t is less than 0.15 mm2 / m, and x is the following expression.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a glass tube, particularly a glass tube for manufacturing a container for storing a pharmaceutical composition. This glass tube facilitates the manufacture of particularly high-quality pharmaceutical containers. Furthermore, the present invention relates to a method for manufacturing an excellent glass tube.

[0002] For the manufacture of glass tubes, particularly for pharmaceutical containers such as ampoules, vials, cartridges or syringes, the so-called Danner process is often used. In the Danner process, the glass melt emerging from the melting tank flows over the outer surface of a rotating tubular body (so-called Danner mandrel), forming a hollow glass melt thereon. The glass melt is drawn from the mandrel, which serves as a forming member, in a predetermined direction towards the front end. The inner profile of the glass tube is substantially determined by the outer contour near the front end of the mandrel.

[0003] Such a glass tube is a semi-finished product for manufacturing the aforementioned container for storing a pharmaceutical composition. As disclosed in German Patent Application Publication No. 102018101842, such a glass tube is typically converted into a container by a hot forming process using a glass processing device.

[0004] European Patent Application Publication No. 3345876 teaches a glass tube for a pharmaceutical container. The glass tube has a certain wall thickness deviation that defines the difference between the maximum wall thickness and the minimum wall thickness with respect to the target wall thickness of the tube. The best exemplary glass tube has a wall thickness deviation of 3%. The wall thickness deviation at that size requires further improvement.

[0005] In many cases, conventional glass tubes have a fairly acceptable uniformity with respect to the inner diameter and the outer diameter, but the accuracy of the hot forming process still needs improvement. In particular, the hot forming process for manufacturing a pharmaceutical container from a glass tube needs to optimize a huge number of parameters in order to consider the variation in the quality of the hot formed product, and thus tends to be difficult to operate stably.

[0006] The object of the present invention is to provide an improved glass tube, and in particular to provide a glass tube that improves the accuracy of parameters and / or simplifies the optimization in the hot forming process.

[0007] In one embodiment, the present invention provides a glass tube having a relative cross-sectional area deviation defined as:

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[0008] At least two cross-sections, for example, those corresponding to QF max and QF min may be spaced apart from each other over at least 0.5 m, at least 0.75 m, at least 1.0 m or up to 1.5 m or up to 1.4 m. In one embodiment, the cross-sections are spaced apart over about 0.5 m, about 0.75 m, about 1.0 m or about 1.5 m. Optionally, QF max is the maximum cross-sectional area of the entire glass tube and QF min is the minimum cross-sectional area of the entire glass tube.

[0009] In one embodiment, the glass tube has less than 0.50 mm 2 per meter, less than 0.45 mm 2 per meter, less than 0.40 mm 2 [[ / m]]]]Less than / m, 0.35mm 2 Less than / m or 0.30mm 2 Relative cross-sectional area deviation less than / m

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[0010] Depending on the circumstances,

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[0011] Surprisingly, it has been found that the cross-sectional area of ​​glass tubes can vary significantly from tube to tube and along the length of the tube. These variations in cross-sectional area along the length of the tube impede the manufacturing accuracy of pharmaceutical containers produced from these glass tubes. Optimizing the parameters of the hot forming process to account for these variations in cross-sectional area is particularly challenging. Glass tubes are semi-finished products that can be used to manufacture syringes, vials, ampoules, cartridges, or other pharmaceutical containers. These containers are typically manufactured by a hot forming process. Hot forming involves heating the glass tube to a temperature at which the glass can be molded into the desired shape. Depending on the mass of glass being heated to the desired temperature, different amounts of heat will be required. However, because pharmaceutical containers are manufactured very quickly according to these processes, it is difficult to adjust the amount of heat used during hot forming. Due to these high production speeds, controlling the heat according to the glass tube characteristics is almost impossible. It has been found that controlling the characteristics of the glass tube in question is essential in order to keep the amount of heat used in the manufacture of pharmaceutical containers constant.

[0012] Using the appropriate amount of heat during the hot forming of glass is essential because the viscosity of the glass changes dramatically with temperature. Between room temperature and the temperature inside the molten vessel, the viscosity of the glass changes by 10 17 The viscosity can change by a factor of two. Therefore, even small temperature variations can have a strong effect on the viscosity of the glass. Different viscosities strongly affect the hot forming of the container. Hot forming parameters must take this behavior into account. Typically, the Vogel-Fulcher-Tammann (VFT) equation is used.

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[0013] In the VFT equation, η is viscosity, A and B are temperature-independent parameters of the substance, T is temperature, and T0 is the Vogel temperature. A, B, and T0 are constant for any particular glass.

[0014] Temperature has a strong influence on viscosity, and it is clear that the temperature dependence can be explained by a constant in the VFT formula. If the temperature is too low, the viscosity of the glass will be too high, making it difficult to form accurate pharmaceutical containers. If the temperature is too high, the viscosity will be too low, which may result in sagging and distorted containers. The specification focuses on the tolerance of the outer diameter of the glass tube and does not consider local deviations and gradients of the cross-sectional area. Glass tubes with excellent uniformity of cross-sectional area have been found to function very well in the subsequent manufacturing processes of pharmaceutical containers, such as syringes, vials, ampoules, and cartridges.

[0015] In one embodiment, the glass of the glass tube may have a value B of at least 4000, at least 4500, or at least 5000. Optionally, the B value may be up to 12000, up to 10000, or up to 9000. T0 may be at least 1°C, at least 10°C, at least 70°C, or at least 200°C. In one embodiment, T0 is in the range of up to 250°C or up to 230°C. A may be less than 0, for example, less than -0.5 or less than -1.0. In one embodiment, A is at least -5.0, at least -4.0, or at least -3.5. Preferably, A can reach -5.0 to 0.0 or -4.0 to 0.0. Glass tubes having the low cross-sectional area deviation and these VFT constants described herein exhibit superior performance in hot forming of containers.

[0016] Depending on the circumstances, the glass may have the following VFT constants: A in the range of -5.0 to 0.0; B in the range of 4000 to 12000; and / or T0 in the range of 1°C to 250°C. In one embodiment, A is in the range of -3.0 to -1.0, B is in the range of 4000 to 9000, and / or T0 is in the range of 200°C to 250°C. Regarding the glass of the glass tube of the present invention, T g It can be in the range of 525°C to 600°C.

[0017] In one embodiment, the present invention provides a glass tube having a uniformity coefficient of at least 0.99, which is the ratio of the minimum cross-sectional area to the maximum cross-sectional area of ​​the entire glass tube. In embodiments of the present disclosure, the glass tube has a uniformity coefficient of at least 0.990, at least 0.993, at least 0.995, or at least 0.998.

[0018] Cross-sectional area deviations have typically been observed to occur as a gradient along the length of the glass tube. The inventors hypothesize that these deviations are due to irregularities in the glass supply mechanism used in glass tube manufacturing. In particular, these deviations may result from instability of the glass strand at the point where the strand first contacts the mandrel. "Instability" means that the strand moves in a direction parallel to the glass drawing direction.

[0019] The glass tube having the cross-sectional area characteristics of the present invention not only provides a highly uniform cross-sectional area along its length, but also a uniform glass mass distribution. The described relative cross-sectional area deviation allows for optimal adjustment of processing parameters in the subsequent hot forming process for manufacturing pharmaceutical containers from the aforementioned glass tube, thereby ultimately resulting in improved pharmaceutical containers and process stability.

[0020] As used herein, the term “glass tube” refers to a hollow glass body used to manufacture containers for storing substances for pharmaceutical use, such as ampoules, vials, syringes, and / or cartridges. A glass tube typically has a wall surrounding a lumen and two open ends.

[0021] Such glass tubes are made of borosilicate glass, more preferably the following oxides (mass percent (%)) relative to the total amount of glass: [Table 1] It can be made of borosilicate glass containing [a specific substance].

[0022] The choice of glass components affects the temperature dependence of the glass viscosity. For example, adding a certain amount of SiO2 reduces the A value and increases the B value and T0 in the VFT equation. The table below summarizes the effect of glass components on the VFT constants. "+" indicates an upward effect, "++" means that each constant increases strongly, "-" indicates a downward effect, and "--" means that each constant decreases strongly with the increase in each glass component. [Table 2]

[0023] Glass may contain SiO2 in a ratio of at least 50% by mass, preferably at least 55% by mass, more preferably at least 60% by mass, and most preferably at least 65% by mass, relative to the total amount of glass. SiO2 is an important network-forming agent in the glass matrix that affects the properties of the glass. In particular, SiO2 is especially important for the chemical resistance of the glass. The SiO2 content in the glass can be up to 90% by mass, preferably up to 85% by mass, and more preferably up to 80% by mass, relative to the total amount of glass. Too much SiO2 content may lead to a significant increase in the softening point of the glass.

[0024] In addition to SiO2, the glass may also contain at least one second network-forming agent. The glass may contain B2O3 as an additional network-forming agent in a proportion of at least 3% by mass, preferably at least 4% by mass, and more preferably at least 6% by mass, relative to the total amount of glass. Due to its network-forming properties, B2O3 substantially supports the stability of the glass. If the B2O3 content is too low, the necessary stability for the borosilicate glass system cannot be guaranteed. Nevertheless, the B2O3 content in the glass is at most 20% by mass, preferably at most 15% by mass, and more preferably at most 12% by mass, relative to the total amount of glass. If the B2O3 content in the glass is extremely high, the viscosity may decrease so drastically that a decrease in crystallization stability must be accepted.

[0025] Furthermore, borosilicate glass may contain aluminum oxide. The addition of aluminum oxide helps improve glass formation and generally aids in chemical resistance. The proportion of aluminum oxide in the glass can be up to 12% by mass, preferably up to 9% by mass, and more preferably up to 7% by mass, relative to the total amount of glass. However, too much aluminum oxide content increases the tendency to crystallize. Preferably, the amount of aluminum oxide in the glass is at least 1% by mass, more preferably at least 2.5% by mass, and most preferably at least 4% by mass, relative to the total amount of glass.

[0026] The glass may contain alkali metal oxides in a proportion of at least 3% by mass, preferably at least 5% by mass, and more preferably at least 6% by mass, relative to the total amount of glass. Both Na2O and K2O may be present in the glass.

[0027] Alkali metal oxides improve the meltability of glass, thus enabling economical production. During glass manufacturing, they function as fluxes. The total amount of alkali metal oxides in the glass should not exceed 20% by mass, preferably 13% by mass, and more preferably 10% by mass. Too high an alkali metal oxide content may impair the weather resistance of the glass, severely limiting its range of applications.

[0028] The proportion of Na2O in the glass can be at least 3% by mass, preferably at least 5% by mass, and more preferably at least 6% by mass, relative to the total amount of glass. On the other hand, the proportion of Na2O in the glass may be limited to a maximum of 15% by mass, preferably a maximum of 10% by mass, and more preferably a maximum of 8% by mass, relative to the total amount of glass.

[0029] The proportion of K2O in the glass can be up to 5% by mass, preferably up to 3% by mass, and more preferably 2% by mass, relative to the total amount of glass.

[0030] Borosilicate glass may also contain additives other than those mentioned above. These additives may be, for example, alkaline earth metal oxides (e.g., BaO, CaO). These can be added to the glass to manipulate its fluidity and fusion properties or chemical resistance. In addition or alternatively, the glass may contain oxides of d-block elemental metals, such as iron oxide (FeO, Fe2O3, or Fe3O4). Iron oxide is a common impurity in the main components of glass, particularly in sand.

[0031] The proportion of BaO in the glass can be up to 6% by mass, preferably up to 4% by mass, and more preferably 3% by mass, relative to the total amount of glass.

[0032] The proportion of CaO in the glass can be up to 5% by mass, preferably up to 3% by mass, and more preferably 2% by mass, relative to the total amount of glass.

[0033] The proportion of Fe2O3 in the glass can be up to 3% by mass, preferably up to 2% by mass, and more preferably 1.5% by mass, relative to the total amount of glass.

[0034] Furthermore, the glass composition may also contain titanium dioxide. The TiO2 content in the glass is a maximum of 10% by mass, preferably a maximum of 8% by mass, and more preferably a maximum of 6% by mass, relative to the total amount of glass. If the TiO2 content is too high, undesirable crystallization of the glass may occur.

[0035] In one embodiment, the glass is as follows (mass%): [Table 3] It can include...

[0036] The cross-sectional area (CSA) is determined using the outer diameter (OD) and wall thickness (WT) of the glass tube at a given cross-section. Here, in the first step, the inner diameter (ID) is:

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[0037] As used herein, the term “outer diameter” refers to the longest distance between two points on the outer surface of the glass tube. These two points are connected by a straight line that is perpendicular to and intersects the longitudinal axis of the glass tube.

[0038] As used herein, the term “inner diameter” refers to the longest distance between two points on the inner diameter of a glass tube. These two points are connected by a straight line that is perpendicular to and intersects the longitudinal axis of the glass tube.

[0039] As used herein, the term "wall thickness" refers to the shortest distance between the inner and outer surfaces of a glass tube.

[0040] At least one of the cross-sections may be located in a first section of the glass tube, and the second cross-section may be located in a second or third section of the glass tube. The first section may extend longitudinally from a first end of the glass tube toward a second end and may have a length of one-third of the length of the tube. The third section may extend longitudinally from a second end of the glass tube toward a first end and may have a length of one-third of the length of the tube. The second section may be located between the first and third sections and may have a length of one-third of the length of the tube in the longitudinal direction.

[0041] The relative cross-sectional area deviation can be based on two single cross-sectional area values ​​that can be determined, for example, in a first section and a third section of a glass tube, or in a first section and a second section, or in a second section and a third section of a glass tube. In one embodiment, one cross-sectional area value is determined in each of the three sections. The relative cross-sectional area deviation can also be based on three or more cross-sectional area values, i.e., 4, 5, 6, 7, 8, 9, 10 or more cross-sectional area values. Each cross-sectional area value can be determined in a particular cross section of the tube. If the cross-sectional area values ​​are determined in three or more cross sections, the distances between each cross section and its adjacent cross sections may be equal or different.

[0042] The glass tubes of this disclosure can have a length of at least 0.50 m, more preferably at least 1.00 m, and particularly preferably at least 1.25 m. The length of the glass tube can be up to 3.00 m, up to 2.00 m, or up to 1.70 m. The present invention provides glass tubes having a desired relative cross-sectional area deviation even when the length exceeds 1.00 m. In one embodiment, the length of the glass tube is about 1.5 m.

[0043] In embodiments of this disclosure, the glass tube has an outer diameter of at least 6.0 mm or at least 10.0 mm. The outer diameter can be up to 55.0 mm, up to 40.0 mm, or up to 25.0 mm. In one embodiment, the outer diameter can be selected from 6 mm to 55 mm or from 6 mm to 25 mm. The wall thickness can vary from 0.3 mm to 3.5 mm. In one embodiment, the wall thickness is at least 0.5 mm, at least 0.7 mm, or at least 1.0 mm. Optionally, the wall thickness can be up to 3.5 mm, up to 3.0 mm, or up to 2.0 mm. The single values ​​of outer diameter and wall thickness are strongly dependent on the application of the glass tube.

[0044] Glass tubes for pharmaceutical containers, particularly for syringes, can be provided with an outer diameter of 6.0 mm to 23.0 mm and / or a wall thickness of 0.75 mm to 2.5 mm. Preferred embodiments include an outer diameter of 6.7 mm to 7.0 mm and a wall thickness of 1.0 mm to 1.2 mm. More preferred embodiments include an outer diameter of 8.00 mm to 8.30 mm and a wall thickness of 0.8 mm to 1.0 mm. Even more preferred embodiments include an outer diameter of 10.0 mm to 11.5 mm and a wall thickness of 1.0 mm to 1.2 mm. Even more preferred embodiments include an outer diameter of 14.0 mm to 15.0 mm and a wall thickness of 1.2 mm to 1.4 mm. Even more preferred embodiments include an outer diameter of 16.5 mm to 17.5 mm and a wall thickness of 1.3 mm to 1.5 mm. Even more preferred embodiments include an outer diameter of 21.0 mm to 23.0 mm and a wall thickness of 1.4 mm to 1.6 mm.

[0045] Glass tubes for pharmaceutical containers, particularly tubes for cartridges, can be provided with an outer diameter of 8.0 mm to 19.0 mm and a wall thickness of 0.75 mm to 1.4 mm. A preferred embodiment includes an outer diameter of 8.5 mm to 8.8 mm and a wall thickness of 0.8 mm to 1.0 mm. A more preferred embodiment includes an outer diameter of 10.5 mm to 11.5 mm and a wall thickness of 1.0 mm to 1.2 mm. A further preferred embodiment includes an outer diameter of 10.5 mm to 11.5 mm and a wall thickness of 0.75 mm to 0.95 mm. A further preferred embodiment includes an outer diameter of 11.0 mm to 12.0 mm and a wall thickness of 0.9 mm to 1.1 mm. A further preferred embodiment includes an outer diameter of 13.5 mm to 14.5 mm and a wall thickness of 0.9 mm to 1.2 mm. A further preferred embodiment includes an outer diameter of 14.0 mm to 15.0 mm and a wall thickness of 1.2 mm to 1.4 mm. A more preferred embodiment includes an outer diameter of 18.0 mm to 18.5 mm and a wall thickness of 1.0 mm to 1.2 mm.

[0046] Glass tubes for pharmaceutical containers, particularly tubes for vials, can have an outer diameter of 6.0 mm to 55.0 mm and a wall thickness of 0.5 mm to 2.5 mm. A preferred embodiment includes an outer diameter of 6.5 mm to 9 mm and a wall thickness of 0.5 mm to 1.6 mm. A more preferred embodiment includes an outer diameter of 8.5 mm to 16.0 mm and a wall thickness of 0.5 mm to 1.7 mm. A further preferred embodiment includes an outer diameter of 14.5 mm to 18.5 mm and a wall thickness of 0.6 mm to 1.7 mm. A further preferred embodiment includes an outer diameter of 17.5 mm to 20.5 mm and a wall thickness of 0.6 mm to 1.7 mm. A further preferred embodiment includes an outer diameter of 19.5 mm to 25.5 mm and a wall thickness of 0.6 mm to 1.7 mm. A further preferred embodiment includes an outer diameter of 22.5 mm to 35.0 mm and a wall thickness of 0.5 mm to 1.8 mm. A further preferred embodiment includes an outer diameter of 29.0 mm to 37.0 mm and a wall thickness of 0.9 mm to 1.7 mm. A further preferred embodiment includes an outer diameter of 32.5 mm to 45.0 mm and a wall thickness of 1.2 mm to 1.8 mm. A further preferred embodiment includes an outer diameter of 40.0 mm to 55.0 mm and a wall thickness of 1.5 mm to 2.2 mm.

[0047] Glass tubes for pharmaceutical containers, particularly for ampoules, can be provided with an outer diameter of 8.0 mm to 30.0 mm and a wall thickness of 0.2 mm to 1.0 mm. Preferred embodiments include an outer diameter of 8.5 mm to 16.0 mm and a wall thickness of 0.3 mm to 0.8 mm. More preferred embodiments include an outer diameter of 14.5 mm to 18.5 mm and a wall thickness of 0.35 mm to 0.85 mm. Even more preferred embodiments include an outer diameter of 17.5 mm to 20.5 mm and a wall thickness of 0.45 mm to 0.85 mm. Even more preferred embodiments include an outer diameter of 19.0 mm to 26.0 mm and a wall thickness of 0.55 mm to 0.9 mm.

[0048] The glass tube of the present invention has an inner diameter. The inner diameter can be at least 3.0 mm, at least 4.0 mm, or at least 8.0 mm. In one embodiment, the inner diameter can be up to 50.0 mm, up to 40.0 mm, up to 30.0 mm, or up to 20.0 mm.

[0049] Generally, achieving a good uniformity coefficient and / or relative cross-sectional area deviation for relatively large cross-sectional areas is relatively difficult. In embodiments of the present invention, the glass tube has an outer diameter of 6 mm to 55 mm and a wall thickness of 0.3 mm to 3.5 mm.

[0050] In one embodiment, the glass tube of the present disclosure is measured in the range of 20°C to 300°C, with a capacity of 3.0 to 8.0 × 10⁻¹⁰. -6 K -1 Or 3.5~7.0 × 10 -6 K -1 Or 4.0~6.0×10 -6 K -1 It has a linear thermal expansion coefficient (CTE) of 6.9 × 10⁻¹. It is beneficial for glass tubes to have a lower CTE. Low-CTE glass tends to generate less stress during hot forming, resulting in a more uniform product. Therefore, in a preferred embodiment, the CTE is 6.9 × 10⁻¹. -6 K -1 The following or 5.9 × 10 -6 K -1The following limitations apply: CTE can be measured according to DIN ISO 7991:1987.

[0051] In a further embodiment, the glass of the glass tube has a refractive index n of 1.45 to 1.55. d More preferably, it has a refractive index of 1.49 to 1.50 or 1.52 to 1.53.

[0052] The density of the glass tube is preferably 1.8 to 3.0 g·cm³. -3 , more preferably 2.0~2.8 g·cm -3 Most preferably 2.2-2.6 g·cm -3 That is the case.

[0053] In embodiments of this disclosure, the outer surface of the glass tube has a protective coating that protects the glass tube from scratches. The protective coating is preferably removable by thermal decomposition occurring at high temperatures. The coating material may include polysorbate, preferably polysorbate 80.

[0054] In one embodiment, the present invention provides a pipe in which at least 90% of the pipe

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[0055] At least 90% of the tubes in the set are 0.70 mm 2 Less than / m, 0.60mm 2 Less than / m or 0.45mm 2 Relative cross-sectional area deviation less than / m

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[0056] At least two cross-sections, e.g., QF max and QF min The corresponding elements may be spaced apart from each other over distances of at least 0.5m, at least 0.75m, at least 1.0m, or up to 1.5m or up to 1.4m. In one embodiment, the cross-sections are spaced apart over distances of approximately 0.5m, approximately 0.75m, approximately 1.0m, or approximately 1.5m. In some cases, QF max QF is the maximum cross-sectional area of ​​the entire glass tube. min This is the minimum cross-sectional area of ​​the entire glass tube.

[0057] A set of glass tubes may include at least 100, or at least 1,000, or at least 3,000 glass tubes, more preferably at least 5,000 glass tubes. In one embodiment, the set is a set of 100, 150, or 200 glass tubes.

[0058] Furthermore, the present invention relates to a method for manufacturing a glass tube, the method being: - A step of applying molten glass to the outer surface of a rotating conical mandrel by guiding the molten glass from a stirring supply tank through an outlet, wherein the molten glass forms a molten glass strand that flows from the outlet onto the outer surface of the mandrel, - The step of forming a hollow glass molten body on a conical mandrel, - A step of drawing a hollow glass molten body from a conical mandrel toward the front end in a predetermined direction in order to form a glass tube, wherein, - The outer surface has a moist zone, in which the glass strand first comes into contact with the conical mandrel. The steps include: continuously monitoring the spatial variation of the wet zone of the applied glass molten material by measuring the horizontal movement of the ends of the glass strand, and assuming that this movement is substantially parallel to the pull direction; - A step of reducing spatial variation by adjusting one or more process parameters selected from the lateral position of the conical mandrel relative to the outlet, the vertical position of the conical mandrel relative to the outlet, the stirring speed in the feed tank, the glass temperature, the inclination angle of the conical mandrel and / or the rotation speed of the conical mandrel, - A step of cooling the hollow glass molten body, - The steps of cutting the cooled molten glass into a glass tube of the desired length and Regarding methods including

[0059] In one embodiment, when the spatial variation σ of the wet zone exceeds a threshold, the rotation speed of the conical mandrel is increased. Here, the rotation speed of the conical mandrel is in the range of 5.0 to 20.0 rpm. In a preferred embodiment, the rotation speed of the conical mandrel is 5.0 to 20.0 rpm, 9.0 to 12.0 rpm, or 9.5 to 11.0 rpm.

[0060] The spatial variation σ is the standard deviation of the horizontal displacement of the strand ends above the wet zone parallel to the pull-out direction. This standard deviation can be calculated from a number of measurements recorded over a period of time. The number of measurements can be 10 or more, 50 or more, or 100 or more. The period can be 30 seconds, 1 minute, or 5 minutes. The spatial variation can be shown as pixels. The threshold can be 2.4 pixels, 2.2 pixels, or 2.0 pixels. A pixel can correspond to approximately 70 μm.

[0061] In one embodiment, in addition to the spatial variation of the glass strand, further data is collected. The data collected can be selected from the group consisting of the wettability of the conical mandrel by the molten glass, the outlet position, the outlet width, and / or the outer shape of the applied glass strand.

[0062] Monitoring of spatial variations and / or further data in the humid zone can be performed using one or more cameras.

[0063] In a more preferred embodiment, the inclination of the conical mandrel is 5° to 45°. In a more preferred embodiment, the volumetric flow rate of the molten glass is 0.4 to 0.55 m³. 3 The temperature is / h. In one embodiment, the temperature of the glass strand in the wet zone is 750°C to 1400°C. In a more preferred embodiment, the drawing speed of the hollow glass molten material is 0.1 to 5 m / s, and optionally 0.3 to 4.0 m / s.

[0064] In one embodiment, the present invention includes a glass tube and / or a set of glass tubes that can be obtained by this method.

[0065] In one embodiment, the present invention provides the use of a glass tube or a set of glass tubes for manufacturing a pharmaceutical container. Preferably, the container is selected from the group consisting of ampoules, vials, syringes and / or cartridges.

[0066] The subject matter of this application is not intended to be limited to the embodiments shown, but will be described in more detail with reference to the subsequent drawings and examples. [Brief explanation of the drawing]

[0067] [Figure 1] A schematic cross-sectional view shows a manufacturing apparatus for a method according to an embodiment of the present invention. [Figure 2] An example of a glass tube 14 having an outer diameter OD, inner diameter ID, and wall thickness WT is shown. [Figure 3] This image shows a camera view of the wet zone where the glass strand first makes contact with the mandrel. [Figure 4] This indicates the degree of movement of the end portion 30 in the X direction during operation. [Figure 5] This shows the distribution of the positions of the glass strand ends during the measurement period.

[0068] Figure 1 shows a schematic cross-sectional view of a manufacturing apparatus for a method according to an embodiment of the present invention.

[0069] The manufacturing apparatus 1 in Figure 1 shows an apparatus for drawing glass tubes 2 by the Danner process. Apparatus 1 comprises a feed tank 3 for containing molten glass 4. In the feed tank, the molten glass 4, which typically has a temperature of over 1300°C, is applied through an outlet 5 onto the outer surface of a rotating conical mandrel 6 called a Danner pipe. The Danner pipe can rotate about an axis substantially parallel to the drawing direction.

[0070] As can be seen from this figure, the conical mandrel 6 is tilted diagonally downward and driven by the power unit 7. The molten glass 4 flows from the outlet 5 on the outer surface of the conical mandrel 6, where a hollow molten glass 8 is formed. The point where the molten glass strand first contacts the conical mandrel 6 as it flows from the outlet 5 toward the conical mandrel 6 is called the wet zone. The hollow molten glass 8 is drawn out of the conical mandrel 6 toward the front end in a predetermined direction. In addition, compressed air is blown through the conical mandrel 6 to prevent the hollow molten glass 8 from collapsing. A so-called drawing onion 9 (Ziehzwiebel in German) is formed at the front end of the conical mandrel 6, and a glass tube 2 is manufactured from this onion by hot forming.

[0071] The formed glass tube 2 is drawn out along a line of support rollers 10 by a drawing device 11 located up to 120 m away from the conical mandrel 6, passing through a monitoring unit 12 that monitors the glass tube 2 for various quality parameters, such as wall thickness and air bubbles. At the end of the line, a cutting device 13 cuts the formed glass tube 2 into individual glass tubes 14.

[0072] The wet zone of the applied glass molten material 4 is continuously recorded by a camera 15 to collect data on the molten material flowing from the outlet 5. The collected data is analyzed by an analysis unit (not shown). Based on these results, spatial variations at the ends of the glass strands in a direction substantially parallel to the drawing direction are reduced by adjusting at least one of the parameters selected from the group consisting of the lateral position of the conical mandrel 6 relative to the outlet 5, the vertical position of the conical mandrel 6 relative to the outlet 5, the stirring speed in the feed tank 3, the glass temperature, the inclination angle of the conical mandrel 6, and / or the rotational speed of the conical mandrel 6.

[0073] Figure 2 shows an example of a glass tube 14 having an outer diameter OD, an inner diameter ID, and a wall thickness WT. The outer diameter can be measured at a first cross section 25 in a first section of the glass tube, a second cross section 26 in a second section of the glass tube 14, and a third cross section 27 in a third section of the glass tube 14. The first cross section 25 may be located at a distance 24 from the first end of the tube. The second cross section 26 may be located at a distance 23 from the first cross section 25. The third cross section 27 may be located at a distance 22 from the second cross section 26. The third cross section 27 may be located at a distance 21 from the second end of the glass tube. Distances 21, 22, 23, and 24 can each be about one-quarter of the length of the tube. In some cases, distances 22 and 23 are approximately the same length.

[0074] Figure 3 shows a camera image of the wet zone where the glass strand first makes contact with the mandrel. The glass strand has an end 30. The X direction is horizontal and substantially parallel to the pull direction. During operation, the end 30 moves in the X direction, which can be monitored by the camera by observing the black and white end 30. These movements are monitored during the process, and process parameters can be adjusted to stabilize the wet zone by reducing the movement of the wet zone in the X direction.

[0075] Figure 4 shows the degree of movement of the end portion 30 in the X direction during operation. The right portion of the figure shows that the movement of the glass strand is stronger and therefore less stable compared to the left portion.

[0076] Figure 5 shows the distribution of the end positions of the glass strands during the measurement period. The figure on the left shows a narrow distribution, while the figure on the right shows more intense movement (instability).

[0077] Examples Example 1 A glass tube 14 with a length of 1.5 m was prepared using the Danner method described in this disclosure. The glass treated by this method had the following VFT constants: A = -1.41, B = 5047.3, and T0 = 224.7°C.

[0078] Three cross-sectional area values ​​were measured along the length of the corresponding glass tube 14. The first value was determined by measuring the outer diameter and wall thickness of the first cross section 25, the second value was determined by measuring the outer diameter and wall thickness of the second cross section 26, and the third value was determined by measuring the outer diameter and wall thickness of the third cross section 27. The sizes of the three cross-sectional areas were compared, and the largest of the three (QF) was selected. max ) and the smallest one (QF min ) was determined. Measurements were repeated for the three pipes. For pipe 1, the maximum cross-sectional area QF max This was measured at the first cross-section 25. Minimum cross-sectional area QF min The measurement was taken at the third cross-section 27. For pipes 2 and 3, the third cross-section 27 was the largest, and the first cross-section 25 was the smallest. The results are shown in the table below. [Table 4]

[0079] Example 2 The glass tube 14 was manufactured according to the Danner process. During operation, the spatial variation of the glass strand (Figure 3) was monitored using a camera 15. The spatial variation is the movement of the end 30 of the glass strand as the glass flows over the conical mandrel 6. Figure 5 shows the distribution of the X position of the black and white end 30 in a first time interval. In this first interval, the rotation speed of the conical mandrel 6 was 9.7 rpm, and the spatial variation σ was approximately 2.35 pixels.

[0080] In the second time interval, the rotation speed was adjusted to reduce the spatial variation σ of the end 30 of the glass strand. After adjustment, the rotation speed was 10.3 rpm, and the spatial variation was reduced to 1.35 pixels.

[0081] The first spacing exhibited a broad distribution of the glass strand end positions, i.e., stronger movement of the glass strands in the wet zone. The second spacing exhibited a narrower distribution. The broad and narrow distributions are shown in Figure 5. In this figure, the left-hand graph shows the narrow distribution, and the right-hand graph shows the stronger movement of the glass strands.

[0082] The influence of process parameters on the uniformity of the glass tube 14 is shown in the table below. [Table 5] [Explanation of symbols]

[0083] 1. Manufacturing plant 2 glass tubes 3. Storage section 4. Molten glass 5 exit 6 Conical Mandrels 7 Power Unit 8. Glass melt 9 Onions 10 Support rollers 11 Extraction device 12 monitoring units 13 Cutting device 14 individual glass tubes 15 Cameras 21 Distance between the second end and the third cross section 22 Distance between the second cross section and the third cross section 23 Distance between the first cross-section and the second cross-section 24 Distance between the first cross section and the first end 25 First cross-section 26. Second cross-section 27 Third Cross Section 30 End of glass strand, X direction

Claims

【Request Item 1】 【Number 1】 A glass tube having a relative cross-sectional area deviation defined as, where, [Math 2] QF ｍａｘ QF is the maximum cross-sectional area of ​​the pipe. ｍｉｎ k is the minimum cross-sectional area of ​​the cross-section, and the cross-sections are spaced apart from each other along the length of the glass tube, with k being 0.0023 m －１ And t is 0.15 mm ２ / m is, and x is, [Math 3] A glass tube that is also at least 10.0 mm² in diameter.

2. The aforementioned relative cross-sectional area deviation is 0.50 mm ２ / m or less or 0.45mm ２ A glass tube according to claim 1, wherein the length is less than / m.

3. The glass tube according to claim 1 or 2, wherein the glass tube has a uniformity coefficient of at least 0.990, at least 0.993, at least 0.995, or at least 0.

998.

4. A glass tube according to any one of claims 1 to 3, having a length of at least 0.50 m, at least 1.00 m, or about 1.5 m.

5. A glass tube according to any one of claims 1 to 4, having an outer diameter of 6.0 mm to 55.0 mm.

6. A glass tube according to any one of claims 1 to 5, having a wall thickness of 0.3 mm to 3.5 mm.

7. The glass has the following VFT constants: A in the range of -5.0 to 0.0; B in the range of 4000 to 12000; T in the range of 1°C to 250°C ０ A glass tube according to any one of claims 1 to 6, having the following:

8. The glass tube according to any one of claims 1 to 7, wherein the glass is borosilicate glass.

9. The following components are expressed in mass percentage (mass%): Table 1 A glass tube according to any one of claims 1 to 8, including the following:

10. A method for manufacturing a glass tube, wherein the method is: - A step of introducing molten glass from a stirring supply tank through an outlet, thereby applying the molten glass to the outer surface of a rotating conical mandrel, so that the molten glass flows from the outlet onto the outer surface of the mandrel and forms a molten glass strand. - The step of forming a hollow glass molten body on the conical mandrel, - A step of forming a glass tube by drawing the hollow glass molten body out of the conical mandrel toward the front end in a predetermined direction, wherein, The outer surface has a wet zone, and the glass strand first comes into contact with the conical mandrel in the wet zone, - A step of continuously monitoring the spatial variation of the wet zone of the applied glass molten material by measuring the horizontal movement of the end of the glass strand, wherein the movement is substantially parallel to the withdrawal direction, - A step of reducing the spatial variation by adjusting one or more process parameters selected from the lateral position of the conical mandrel relative to the outlet, the vertical position of the conical mandrel relative to the outlet, the stirring speed in the feed tank, the glass temperature, the inclination angle of the conical mandrel and / or the rotational speed of the conical mandrel, - A step of cooling the hollow glass molten body, - The steps of cutting the cooled glass molten body into a glass tube of a desired length. Includes, A method wherein, when the spatial variation σ of the wet zone exceeds a threshold, the rotational speed of the conical mandrel is increased, and the rotational speed of the conical mandrel is within the range of 5.0 to 20.0 rpm.

11. The method according to claim 10, wherein the rotational speed of the conical mandrel is in the range of 9.0 to 12.0 rpm or in the range of 9.5 to 11.0 rpm.

12. Use of one or more glass tubes according to any one of claims 1 to 9 for the manufacture of pharmaceutical containers, such as ampoules, vials, syringes and / or cartridges.

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