GLASS ARTICLE AND METHOD FOR PRODUCING A GLASS ARTICLE

Abstract

The invention relates to a method for producing a glass article. The method includes the step of producing a glass body from a glass material and the further step of bringing the glass body, at a primary temperature which is at most 50 Kelvin below and at most 30 Kelvin above the Littleton softening point of the glass material, into contact with a liquid cooling agent which has a cooling agent temperature which is at least 200 Kelvin and at most 550 Kelvin below the primary temperature.

Claims

1. A method for producing a glass article, characterized by steps as follows: a. producing a glass body (1) from a glass material, and b. contacting the glass body (1), at a primary temperature which lies at most 50 kelvins below and at most 30 kelvins above the Littleton softening point of the glass material, with a liquid cooling agent (4) which exhibits a cooling agent temperature which lies at least 200 kelvins and at most 550 kelvins, more particularly at least 200 kelvins and at most 450 kelvins, below the primary temperature.

2. The method as claimed in claim 1, characterized in that the primary temperature and the cooling agent temperature are selected in such a way that a. the initial cooling rate is in the range from 80 kelvins to 120 kelvins per second, more particularly in the range from 90 kelvins to 110 kelvins per second, or is 100 kelvins per second, or that b. the initial cooling rate is not less than 80 kelvins per second, more particularly not less than 100 kelvins per second.

3. The method as claimed in claim 1, characterized in that the primary temperature lies at most 30 kelvins below and at most 10 kelvins above the Littleton softening point of the glass material or in that the primary temperature corresponds to the Littleton softening point.

4. The method as claimed in claim 1, characterized in that the glass body (1) is produced from a melt of the glass material and in a first cooling process is cooled outside the cooling bath (3) until the primary temperature is reached and then immediately thereafter is contacted with the liquid cooling agent (4).

5. The method as claimed in claim 1, characterized in that the chilled glass body (1) prior to contacting is heated to the primary temperature.

6. The method as claimed in claim 5, characterized in that for heating, the glass body (1) is transferred into at least one kiln (5).

7. The method as claimed in claim 6, characterized in that the kiln (5) has a kiln temperature which corresponds to the Littleton softening point of the glass material or which lies at most 50 kelvins below and at most 30 kelvins above the Littleton softening point of the glass material.

8. The method as claimed in claim 6, characterized in that the kiln (5) has a kiln temperature which lies in a range from 10 kelvins to 40 kelvins above the primary temperature.

9. The method as claimed in claim 6, characterized in that the glass body (1) is a hollow body with walls which have a wall thickness, and in that the glass body (1) remains in the kiln (5) for a heating time in the range from 35 seconds to 90 seconds, more particularly from 45 seconds to 70 seconds, per millimeter of wall thickness, more particularly for a heating time of 55 seconds per millimeter of wall thickness.

10. The method as claimed in claim 6, characterized in that the glass body (1) has a flat embodiment and has a thickness, and in that the glass body remains in the kiln (5) for a heating time in the range from 35 seconds to 90 seconds, more particularly from 45 seconds to 70 seconds, per millimeter of thickness, more particularly for a heating time of 55 seconds per millimeter of wall thickness.

11. The method as claimed in claim 5, characterized in that the heating takes place in a multistage, more particularly two-stage, process.

12. The method as claimed in claim 11, characterized in that the glass body (1) is first heated to a first temperature at a first heating rate and then is heated to the primary temperature at a second heating rate which is above the first heating rate.

13. The method as claimed in claim 11, characterized in that the glass body (1) is heated first at a first kiln temperature and thereafter at a second kiln temperature which is higher than the first kiln temperature.

14. The method as claimed in claim 13, characterized in that the glass body (1) is exposed to the second kiln temperature for a heating time in the range from 60 seconds to 120 seconds, more particularly from 80 seconds to 100 seconds, or for a heating time of 90 seconds.

15. The method as claimed in claim 1, characterized in that the contacting takes place by immersion of the glass article in a cooling bath which contains the cooling agent.

16. The method as claimed in claim 1, characterized in that the contacting takes place by spraying or by sprinkling with the cooling agent.

17. The method as claimed in claim 1, characterized in that the cooling agent (4) contains an oil and/or a metal and/or a salt melt or in that the cooling agent is an oil or a metal or a salt melt.

18. The method as claimed in claim 1, characterized in that the glass material is an alkali-containing silicate glass, more particularly an alkali metal-alkaline earth metal silicate glass, especially a soda-lime glass, or a borosilicate glass or an aluminosilicate glass.

19. The method as claimed in claim 1, characterized in that the glass material has a silicon dioxide fraction of more than 58% (percent by mass) and of less than 85% (percent by mass), more particularly of more than 70% (percent by mass) and of less than 74% (percent by mass).

20. The method as claimed in claim 1, characterized in that the glass material has an alkali metal oxide fraction, more particular sodium oxide fraction and/or lithium oxide fraction, in the range from 5% (percent by mass) to 20% (percent by mass), more particularly in the range from 10% (percent by mass) to 14.5% (percent by mass) or in the range from 12% (percent by mass) to 13.5% (percent by mass).

21. The method as claimed in claim 1, characterized in that the glass material has a potassium oxide fraction of at most 7% (percent by mass), more particularly of at most 3% (percent by mass) or of at most 1% (percent by mass), or in that the glass material has a potassium oxide fraction in the range from 0.5% (percent by mass) to 0.9% (percent by mass).

22. The method as claimed in claim 1, characterized in that the glass material has a boron trioxide fraction of less than 15% (percent by mass), more particularly of at most 5% (percent by mass).

23. The method as claimed in claim 1, characterized in that the liquid coolant is contacted progressively or at time intervals, more particularly constant time intervals, with a regeneration material, more particularly a solid regeneration material.

24. A glass article produced by means of a method as claimed in claim 1.

25. The glass article as claimed in claim 24, characterized in that the glass article is embodied as a hollow body, more particularly a drinking glass, a vase, a tumbler, a bowl or a bottle.

26. The glass article as claimed in claim 25, characterized in that the glass article is embodied as a dishware article, more particularly as a plate.

27. The glass article as claimed in claim 25, characterized in that the glass article is embodied as flat glass.

Description

BRIEF DESCRIPTION OF THE DRAWING VIEWS

[0050] In the drawing, the subject matter of the disclosure is represented illustratively and schematically and is described below with reference to the figures, where elements that are the same or have the same effect, even in different exemplary embodiments, are usually provided with the same reference signs. In the figures,

[0051] FIG. 1 shows a schematic representation of a first exemplary embodiment of a method sequence of the disclosure,

[0052] FIG. 2 shows a schematic representation of a second exemplary embodiment of a method sequence of the disclosure, and

[0053] FIGS. 3 to 6 show schematic representations of a third exemplary embodiment of a method sequence of the disclosure.

DETAILED DESCRIPTION

[0054] FIG. 1 shows a schematic representation of a first exemplary embodiment of a method sequence of the disclosure, in which in a first step a glass body 1 is produced from a glass material in a production plant 2. This may take place for example by pressing, blowing, sucking or a combination of these techniques. More particularly the production plant 2 may operate according to the blow-and-blow or press-and-blow method. In the exemplary embodiment, the glass body is embodied as a drinking glass.

[0055] In a first cooling process, the glass body 1 is cooled outside a cooling bath 3 until a primary temperature has been reached. The primary temperature lies at most 50° Kelvin below and at most 30° Kelvin above the Littleton softening point of the glass material.

[0056] As soon as the primary temperature has been reached, the glass body 1 is immersed completely in the cooling bath 3. The cooling bath 3 contains a liquid cooling agent 4, which exhibits a cooling agent temperature which lies at least 200 kelvins and at most 500 kelvins below the primary temperature. The primary temperature and the cooling agent temperature are preferably selected such that the initial cooling rate is around 100 kelvins per second.

[0057] After a predetermined time has elapsed since the immersion, this time being preferably longer than 5 minutes, more particularly longer than 10 minutes, the glass body 1 is withdrawn from the cooling bath 3 and cooled further, and cleaned, in a cooling position outside the cooling bath 3.

[0058] In particular it may be advantageous for multiple glass bodies 1 to be treated simultaneously in the manner described above. In particular it is possible for a multiplicity of glass bodies 1 to be immersed simultaneously in the cooling bath 3 and removed from the cooling bath 3 for further processing after the cooling procedure, together or in succession.

[0059] FIG. 2 shows a schematic representation of a second exemplary embodiment of a method sequence of the disclosure, in which in a first step a glass body 1 is produced from a glass material in a production plant 2. This may take place, for example, by pressing, blowing, sucking or a combination of these techniques. More particularly the production plant 2 may operate according to the blow-and-blow or press-and-blow method.

[0060] In a further step, the glass body 1 is cooled conventionally first to room temperature. In this state the glass body 1 can advantageously be easily transported and/or assembled with other glass bodies 1 to form a batch for joint further working.

[0061] The glass body 1 is subsequently heated until the glass body 1 has reached the primary temperature. For this purpose the glass body 1 is transferred into a kiln 5. The kiln 5 has a kiln temperature which corresponds to the Littleton softening point of the glass material or which lies at most 50 kelvins below and at most 30 kelvins above the Littleton softening point of the glass material. Advantageously the kiln 5 may in particular have a kiln temperature which lies in a range from 10 kelvins to 40 kelvins above the primary temperature.

[0062] Glass bodies 1 which are embodied as hollow bodies having walls with a wall thickness remain in the kiln 5 for a heating time in the range from 35 seconds to 45 seconds per millimeter of wall thickness, more particularly for a heating time of 40 seconds per millimeter of wall thickness. Glass bodies which have a flat embodiment and a thickness remain in the kiln 5 for a heating time in the range from 35 seconds to 45 seconds per millimeter of thickness, more particularly for a heating time of 40 seconds per millimeter of thickness.

[0063] Following removal from the kiln 5, the glass body 1 is immersed immediately and completely in the cooling bath 3. The cooling bath 3 contains a liquid cooling agent 4 which exhibits a cooling agent temperature which lies at least 200 kelvins and at most 550 kelvins below the primary temperature. The primary temperature and the cooling agent temperature are preferably selected such that initial cooling rate is 100 kelvins per second.

[0064] After a predetermined time has elapsed from the immersion, this time being preferably longer than 5 minutes, more particularly longer than 10 minutes, the glass body 1 is withdrawn from the cooling bath 3 and is further cooled, and finally cleaned, in a cooling position outside the cooling bath 3.

[0065] It is possible advantageously, in particular, for multiple glass bodies 1 to be treated simultaneously in the manner described above. More particularly a multiplicity of glass bodies 1 may be heated simultaneously in the kiln 5 and then immersed together in the cooling bath 3 and, after the cooling procedure, removed together from the cooling bath 3 for further working.

[0066] FIGS. 3 to 6 show schematic representation of a third exemplary embodiment of a method sequence of the disclosure, in which in a first step a glass body 1 is produced from a glass material in a production plant 2. This may take place, for example, by pressing, blowing, sucking or a combination of these techniques. More particularly the production plant 2 may operate according to the blow-and-blow or press-and-blow method. In a further step, the glass body 1 is conventionally cooled first to room temperature (FIG. 3). In this condition, the glass body 1 advantageously can be easily transported and/or assembled with other glass bodies 1 to form a batch for joint further working.

[0067] The glass body 1 is subsequently heated in a two-stage process until the glass body 1 has reached the primary temperature. For this purpose the glass body 1 is transferred into a kiln 5 which has a first kiln region 6 having a first kiln temperature and a second kiln region having a second kiln temperature which is higher than the first kiln temperature.

[0068] The glass body (1) is first transferred to the first kiln region 6 (FIG. 4), where it is heated to a first temperature. The first temperature lies preferably in a range from 50 kelvins below to 100 kelvins above the transformation temperature of the glass material, more particularly in a range from 0 kelvin to 50 kelvins above the transformation temperature of the glass material.

[0069] The glass body (1) is thereafter transferred to the second kiln region 7 (FIG. 5), where it is heated to the primary temperature, which lies at most 50 kelvins below and at most 30 kelvins above the Littleton softening point of the glass material.

[0070] The glass body 1 is then removed from the kiln 5 and immersed, immediately and completely, in the cooling bath 3 (FIG. 6). The cooling bath 3 contains a liquid cooling agent 4 which exhibits a cooling agent temperature which lies at least 200 kelvins and at most 550 kelvins below the primary temperature. The primary temperature and the cooling agent temperature are preferably selected such that initial cooling rate is 100 kelvins per second.

[0071] After a predetermined time has elapsed from the immersion, this time being preferably longer than 5 minutes, more particularly longer than 10 minutes, the glass body 1 is withdrawn from the cooling bath 3 and is cooled further, and finally cleaned, in a cooling position outside the cooling bath 3.

[0072] It is possible advantageously, in particular, for multiple glass bodies 1 to be treated simultaneously in the manner described above. More particularly a multiplicity of glass bodies 1 may be heated simultaneously in the kiln 5 and then immersed together in the cooling bath 3 and, after the cooling procedure, removed together from the cooling bath 3 for further working.

LIST OF REFERENCE SIGNS

[0073] 1 glass body [0074] 2 production plant [0075] 3 cooling bath [0076] 4 liquid cooling agent [0077] 5 kiln [0078] 6 first kiln region [0079] 7 second kiln region