Search

CN-115872021-B - Glass container and method for manufacturing same

CN115872021BCN 115872021 BCN115872021 BCN 115872021BCN-115872021-B

Abstract

The invention relates to a glass container, in particular for containing a formulation, comprising a hollow body having an inner volume, in particular for containing the formulation, wherein the hollow body comprises a wall having an inner surface and an outer surface opposite the inner surface, the inner surface delimiting the inner volume of the hollow body, wherein the wall comprises at least in a partial region a region having a compressive stress, wherein the region formed having a compressive stress adjoins the outer surface such that the outer surface is compressively prestressed at least in the partial region, and wherein the inner surface of the wall opposite the partial region is free from compressive stress and preferably under tensile stress, and to a method for chemically prestressing the glass container, in particular for containing a formulation.

Inventors

  • A - Portland Gus Christopher
  • S. Tratsky
  • F. MAURER
  • P. THOMAS

Assignees

  • 肖特股份有限公司

Dates

Publication Date
20260505
Application Date
20191105
Priority Date
20181105

Claims (20)

  1. 1. A container comprising or consisting of glass, said container comprising a hollow body having an internal volume, Wherein the hollow body comprises a wall having an inner surface and an outer surface opposite the inner surface, the inner surface defining the interior volume of the hollow body, Wherein the wall comprises, at least in part, a region having compressive stress, Wherein the region of compressive stress is formed on a wall adjacent the outer surface, Wherein in the center of the wall, i.e. in the center between the outer surface and the inner surface, the tensile stress CT is expressed as CT≥0 MPa and CT <15 MPa.
  2. 2. The container of claim 1, wherein the container is for containing a formulation, the formulation being contained in the interior volume of the hollow body.
  3. 3. The container according to claim 1 or 2, wherein the tensile stress CT is 5MPa or less.
  4. 4. Container according to claim 1 or 2, wherein the wall of the hollow body forms at least one opening and/or a rim and/or a neck and/or a shoulder and/or a side wall and/or a heel and/or a bottom.
  5. 5. The container of claim 4, wherein the regions comprising compressive stress are formed adjacent to and/or abutting the shoulder, neck, rim, sidewall, heel and/or bottom, respectively.
  6. 6. The container according to any one of claims 1 or 2, wherein the container is a vial, ampoule, syringe or cartridge.
  7. 7. A container according to any one of claims 1 or 2, wherein, as a result of the region of compressive stress being formed on the wall adjoining the outer surface, compressive stress is formed in the region of the outer surface up to the depth DOL, and there is an asymmetric profile of stress patterns from the outer surface of the wall to the opposite inner surface in a radial direction relative to the centre of the wall.
  8. 8. The container according to claim 1 or 2, wherein in the region having compressive stress in the outer surface, the inner surface tension is formed as tensile stress on the inner surface of the wall opposite to the region, and the tensile stress IST is expressed as IST≥0 MPa and IST≥30 MPa.
  9. 9. The container of claim 8, wherein IST is 20 MPa.
  10. 10. The container of claim 8, wherein IST is 15 MPa or less.
  11. 11. The container of claim 8, wherein IST is 5 MPa.
  12. 12. A container according to claim 1 or 2, wherein in the region of compressive stress in the outer surface, the tensile stress on the opposite inner surface of the wall is expressed as: , Where DOL represents the depth of the region where compressive stress exists, T represents the thickness of the wall, and CS represents the compressive stress on the outer surface.
  13. 13. A container according to claim 1 or 2, wherein in the region of compressive stress in the outer surface the level of tensile stress at the centre of the wall is approximately equal to the level of tensile stress on the opposite inner surface of the wall, and wherein the level of tensile stress at the centre of the wall up to the inner surface of the wall is subjected to only small fluctuations, within +/-10%.
  14. 14. The container of claim 13, wherein the range of fluctuation is within +/-5%.
  15. 15. A container according to claim 1 or 2, wherein for a region having compressive stress in the outer surface, the thickness or depth DOL of the near-surface compressively pre-stressed region is no more than 15% relative to the wall thickness or wall width in that region.
  16. 16. The container of claim 15, wherein the thickness or depth DOL of the near-surface compressive pre-stressed region is no more than 10% relative to the wall thickness or wall width in the region.
  17. 17. The container of claim 15, wherein the thickness or depth DOL of the near-surface compressive pre-stressed region is no more than 8% relative to the wall thickness or wall width in the region.
  18. 18. The container of claim 15, wherein the thickness or depth DOL of the near-surface compressive pre-stressed region is no more than 6% relative to the wall thickness or wall width in the region.
  19. 19. Container according to claim 1 or 2, characterized in that the distribution of alkali elements introduced into the glass during chemical prestressing decreases monotonically from the outer surface towards the opposite inner surface of the wall in a region of 0.5 μm from the outer surface up to a region of 0.5 μm from the inner surface when prestressing is introduced chemically in a region of compressive stress.
  20. 20. The container of claim 19, wherein the alkali metal element is potassium.

Description

Glass container and method for manufacturing same The invention relates to a division application of China patent application 201911071359.7 of 2019, 11 and 5, named as a glass container and a manufacturing method thereof. Technical Field The present invention relates generally to a glass container and a method for manufacturing the same, in particular a glass container having a specific strength, preferably for containing a formulation, in particular a cosmetic, medical or pharmaceutical formulation. Background Glass containers or so-called glass primary packages for holding cosmetic, medical or pharmaceutical preparations are well known, which can be manufactured in various geometries and quality classes. Such containers are suitable for storing, transporting or even administering the formulation. They can be manufactured in large quantities at low cost, for example as cartridges, vials or ampoules. Such a container may be made of glass, but also of plastic, for example. However, since glass is chemically inert, glass containers have advantages, for example, in terms of the lifetime of the package or potential contamination of the formulation contained therein. Typically, the glass containers are cleaned prior to filling, then refilled, sealed, and shipped or packaged into larger containers. This is done by means of a suitable device, which is typically fully automated. During this process, the container is subjected to specific strains. On the one hand, during transport, the containers may come into contact with or strike each other and may also be impacted by radially or axially large forces. This in turn can lead to surface damage, e.g. scratches on the outer surface of the container, or even to cracks. Sometimes, the high forces or impacts also have an effect on the extent to which the container is broken, especially if the container is made of glass. This is a major problem, especially in the case of primary packages of medicaments, especially in terms of compliance with cleanliness requirements. Another relevant factor for a drug container may be the internal pressure that affects the container during filling of the container with e.g. a liquid formulation. In adverse situations, excessive pressure during filling or during lyophilization may lead to container explosion. This problem is even further exacerbated if the container has been subjected to previous damage, for example due to the forces described above. The application document WO 2013/130721 A1 proposes a solution. An aluminosilicate glass container is provided having at least one pre-stressed side wall. Prestressing the side walls should ensure that if a crack forms that penetrates the side walls and may jeopardize the sterility of the interior of the container, the container is severely damaged to such an extent that it can no longer be used for its intended purpose. Thus, it is disclosed to introduce a tensile stress into the sidewall, in particular into the central region of the sidewall, which is above a threshold of 15MPa, and the exemplary embodiments describe only containers with compressive pre-stressing on the outside and inside. This compressive prestressing can be achieved by ion exchange on the near-surface layer of the glass in a salt water bath with an elevated temperature. In certain types of glass, it is the function of exchanging smaller ions (e.g., sodium ions) present in the near-surface layer of the glass in a brine bath for larger ions (e.g., potassium ions) in the brine. This creates compressive stress in the surface region, thereby increasing the strength of the glass. However, during this process, the inner surface of the glass container (i.e. the surface that is thus subsequently contacted with the filling agent) also undergoes such ion exchange and thus also chemical changes. For some formulations, this may be disadvantageous, which means that the range of possible uses of such glass containers is limited. Thus, the types of glasses that are typically allowed for medical use are also severely altered, at least on their inner surfaces, resulting in failure of or re-approval of these glass types in medical applications. Further processes are known in which further treatments, in particular cleaning or dealkalization of the inner surfaces, are carried out downstream of the chemical prestressing process. Indeed, due to this post-treatment it is possible to reduce the release of alkali into the drug, but this cleaning/dealkalization treatment leads to further chemical modification of the glass surface, so that here again approval of the corresponding glass container as a primary packaging means for the drug is unavoidable. In addition to this, only a shallow depth can be reached to remove again the material introduced through the brine bath. Disclosure of Invention It is therefore an object of the present invention to provide a drug container which has a higher strength with respect to radial or axial forces impinging