Production method of glass article

Abstract

To provide a technique capable of removing a deposit strongly adhering to glass.SOLUTION: A production method of a glass article includes: a heat processing process of heat processing a glass intermediate of a molded glass article; and a removing process of subjecting a deposit caused by a specific component contained in the glass intermediate by the heat processing process to blast treatment with a dry ice to remove the deposit from the glass intermediate.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The technology disclosed in this specification relates to a method for manufacturing a glass article, which includes a thermal processing step. [Background technology]

[0002] Patent Document 1 discloses a method for cleaning the surface of a glass sheet. The glass sheet is obtained by forming a glass ribbon into a plate shape on molten tin metal. The cleaning method includes a step of removing foreign matter on the surface of the glass sheet caused by molten tin metal by colliding particles with the surface of the glass sheet. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-62349 A Summary of the Invention [Problem to be solved by the invention]

[0004] When glass is subjected to thermal processing, components contained in the glass may evaporate and adhere to the glass surface as solid deposits. If the deposits adhere firmly to the glass, they may not be able to be removed by merely colliding with particles.

[0005] The present specification provides a technique capable of removing deposits that adhere strongly to glass. [Means for solving the problem]

[0006] A first embodiment of the technology disclosed in this specification is a method for manufacturing a glass article, comprising a thermal processing step of thermally processing a glass intermediate of the shaped glass article, and a removal step of performing a blasting treatment with dry ice on deposits resulting from a specific component contained in the glass intermediate by the thermal processing, thereby removing the deposits from the glass intermediate.

[0007] In the blasting treatment using dry ice, the collision of the dry ice and the cooling of the deposit by the dry ice cause cracks in the deposit, and the volume change caused by the sublimation of the dry ice causes the deposit to peel off from the glass intermediate body, thereby making it possible to remove the deposit that is firmly attached to the glass.

[0008] A second form of the technology disclosed in the present specification is the first form, wherein the specific component includes at least one component of silicon (Si), boron (B), aluminum (Al), sodium (Na), and potassium (K).

[0009] Silicon (Si), boron (B), aluminum (Al), sodium (Na) and potassium (K) contained in the glass intermediate are components that easily evaporate during the heating process. Therefore, the deposits caused by the above specific components need to be removed by blasting with dry ice, and can be effectively removed by blasting with dry ice.

[0010] As a third aspect of the technology disclosed in the present specification, in the first or second aspect, the glass article may contain, by mass%, 5% or more in total of B2O3 and R2O (R represents lithium (Li), sodium (Na), and potassium (K)).

[0011] In the case of the above-mentioned glass article, the generation of deposits due to specific components evaporating from the glass intermediate body during the heating step becomes noticeable, and these can be effectively removed by blasting treatment with dry ice.

[0012] A fourth form of the technology disclosed in the present specification is any one of the first to third forms, wherein the thermal processing includes laser processing in which a laser is irradiated to at least one of a surface and an interior of the glass intermediate body.

[0013] When glass is heated by laser irradiation, high energy is imparted to the glass from the laser. This can cause deposits to adhere firmly to the glass. By performing a blasting process with dry ice, it is possible to remove the firmly adhered deposits.

[0014] A fifth aspect of the technology disclosed in the present specification is any one of the first to fourth aspects, wherein in the blasting treatment, a collision pressure of the dry ice may be 50 MPa or less.

[0015] By controlling the collision pressure of the dry ice, it is possible to prevent the glass from being damaged by the dry ice during the blasting process.

[0016] A sixth aspect of the technology disclosed in the present specification is any one of the first to fifth aspects, wherein the glass article has a plate shape, and the thermal processing may modify at least one of a surface and an interior of the glass intermediate by heating.

[0017] Dry ice blasting can remove deposits that result from thermal processing to modify the glass.

[0018] A seventh form of the technology disclosed in the present specification is any one of the first to fifth forms above, wherein the glass article has a tubular shape, the thermal processing includes a face-burning process for heating an end of the glass intermediate, and the blasting process may involve ejecting the dry ice from an ejection nozzle from the outside of one end of the glass intermediate toward the deposit that adheres to the inner surface of the glass intermediate by the face-burning process.

[0019] When manufacturing a tubular glass article, a face-burning process is performed in which the end of the tubular glass article is heated to round off the corners of the end. When the face-burning process is performed, deposits may adhere to the inner peripheral surface of the tubular glass article. According to the above configuration, the deposits adhered to the inner peripheral surface of the tubular glass article can be removed.

[0020] An eighth aspect of the technology disclosed in this specification is the seventh aspect, wherein, in the blasting treatment, the position of the injection outlet of the injection nozzle and the inner surface of the glass intermediate body facing the injection outlet may be changed relative to each other.

[0021] According to this configuration, the dry ice can be collided with the inner peripheral surface of the tubular shape over a wide area, so that the deposits adhering to the inner peripheral surface of the tubular shape can be effectively removed over a wide area.

[0022] A ninth form of the technology disclosed in the present specification is the seventh or eighth form, wherein the removal step may include a process of flowing a gas from a second end opposite to the first end of the tubular shape toward the first end.

[0023] According to this configuration, deposits that have been peeled off from the inner peripheral surface of the tubular shape by the blasting process can be expelled from inside the tubular shape by the gas. [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 shows a plan view of a glass article according to a first embodiment. [Diagram 2] 1 shows a flowchart of a method for manufacturing a glass article according to a first embodiment. [Diagram 3] 1 is a schematic front view of a blasting treatment apparatus according to a first embodiment. [Figure 4] FIG. 2 shows a schematic diagram for explaining the blasting process of the first embodiment. [Diagram 5] 1 shows a table for explaining the conditions of the blasting experiment of the first embodiment. [Figure 6] FIG. 2 shows a perspective view of a glass article according to a second embodiment. [Figure 7] 13A and 13B are schematic diagrams for explaining the thermal processing step of the second embodiment. [Figure 8] FIG. 13 is a schematic front view of a blasting treatment apparatus according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] (First Example) A method for manufacturing a glass article 10 will be described with reference to the drawings. As shown in FIG. 1, the glass article 10 is a semiconductor wafer support glass. The glass article 10 supports a semiconductor wafer such as silicon. The glass article 10 has a circular flat plate shape. The glass article 10 is preferably borosilicate glass. The glass article 10 may contain, for example, silicon dioxide (SiO2) and boron oxide (B2O3) as main components, and may also contain aluminum oxide (Al2O3), sodium oxide (Na2O), potassium oxide (K2O), calcium oxide (CaO), and magnesium oxide (MgO).

[0026] In a modified example, the glass article 10 may be used for purposes other than as a semiconductor wafer support glass. In this case, the glass article 10 may have a flat plate shape other than a circle, such as a square, or may have a plate shape having irregularities, curves, or the like other than a flat plate. The glass article 10 may be glass other than borosilicate glass, such as alkali-free glass, aluminosilicate glass, quartz glass, or LSA (Li2O-SiO2-Al2O3)-based glass.

[0027] The components of the glass article 10 are not limited to the above-mentioned components. The glass article 10 may contain at least one of silicon (Si), boron (B), aluminum (Al), sodium (Na), and potassium (K). The glass article 10 may contain, in mass %, 5% or more, 10% or more, 15% or more, 20% or more, and particularly 30% or more of B2O3 and R2O (R represents at least one of lithium (Li), sodium (Na), and potassium (K)). For example, the glass article 10 may contain, in mass %, 5%, 10% or more, 15% or more, 20% or more, and particularly 30% or more of B2O3, and may contain at least one selected from Na2O, K2O, and Li2O in an amount of 5% or more, 10% or more, 15% or more, 20% or more, and particularly 30% or more. The glass article 10 may contain, in terms of mass %, a total of 50% or less, and particularly 40% or less, of B2O3 and R2O (R represents at least one of lithium (Li), sodium (Na), and potassium (K)).

[0028] The glass article 10 has a processed portion 12 inside that displays identification information for identifying the glass article 10. The processed portion 12 is disposed inside the glass article 10, i.e., at an intermediate position between the front surface and the back surface. The identification information includes a character string, a symbol, and a one-dimensional or two-dimensional code.

[0029] (Method of manufacturing glass article) Next, a method for manufacturing the glass article 10 will be described with reference to Fig. 2. In the manufacturing method, a glass intermediate preparation step is performed in S12. In the glass intermediate preparation step, a glass intermediate 50 (see Fig. 3) is placed in a thermal processing device (not shown).

[0030] The thermal processing device is a device that performs thermal processing on the glass intermediate 50. The thermal processing device creates the processed portion 12 by irradiating the glass intermediate 50 with a laser to modify the inside of the glass. For example, the thermal processing device modifies the inside of the glass by irradiating it with a femtosecond laser. The thermal processing device may be a laser scribing device. When glass is modified, at least one of the structure and properties of the glass is changed. In S14, the thermal processing device performs thermal processing on the glass intermediate 50. In a modified example, the thermal processing device may irradiate the glass intermediate 50 with a laser to modify the surface of the glass or both the surface and the inside of the glass.

[0031] The thermal processing device locally heats the inside of the glass intermediate 50 (in a modified example, the surface or both the surface and the inside), thereby locally changing at least one of the structure and properties of the glass, i.e., locally modifying the glass. The thermal processing device does not change the external shape of the glass intermediate 50 by heating the entire glass intermediate 50. For this reason, the thermal processing step is not aimed at the external shape of the glass intermediate 50 before and after the thermal processing step. The external shape of the glass intermediate 50 is the same as that of the glass article 10, except for unintended deformations during the thermal processing step.

[0032] In a modified example, the thermal processing device may thermally process the surface of the glass intermediate 50. For example, the thermal processing device may engrave the identification information, which is the processed portion 12, on the surface of the glass intermediate 50 by irradiating the surface of the glass intermediate 50 with a laser. In this case, the outer shape of the glass intermediate 50 may be the same as that of the glass article 10, except for local surface processing by thermal processing and unintended deformation in the thermal processing step. Also, for example, the thermal processing device may engrave the identification information, which is the processed portion 12, on the surface of the glass intermediate 50 by irradiating the surface of the glass intermediate 50 with a laser, or may perforate the glass intermediate 50.

[0033] When the thermal processing step is performed, at least one of silicon, boron, aluminum, lithium, sodium, and potassium contained in the glass intermediate body 50 evaporates and solidifies on the surface of the glass intermediate body 50 located around the processed portion 12. As a result, a deposit of at least one of silicon, boron, aluminum, lithium, sodium, and potassium adheres to the surface of the glass intermediate body 50.

[0034] In S18, a removal step is performed. In the removal step, deposits generated by the thermal processing are removed from the surface of the glass intermediate body 50. In the removal step, a blasting process is performed in which dry ice is injected onto the surface of the glass intermediate body 50. As shown in Fig. 3, the glass intermediate body 50 is placed on a stage 104, and an injection nozzle 102 is disposed above the processed portion 12. Dry ice particles are injected from an injection port 102a located at the lower end of the injection nozzle 102, causing the dry ice to collide with the surface of the glass intermediate body 50.

[0035] 4A and 4B are schematic diagrams showing how the deposit 54 is removed in the removal step. As shown in FIG. 4A, the deposit 54 is attached to the surface 52 of the glass intermediate 50. When particles of dry ice D are injected from the injection nozzle 102 toward the surface 52 of the glass intermediate 50, the dry ice D collides with the surface 52 and a dry ice film E is formed as shown in FIG. 4B. The dry ice film E causes thermal contraction (i.e., thermal shock) in the glass intermediate 50 and the deposit 54. Due to the difference in thermal contraction between the glass intermediate 50 and the deposit 54, minute cracks 56 are generated in the deposit 54, making it easy for the surface 52 and the deposit 54 to peel off from each other.

[0036] As shown in Fig. 4(C), when the dry ice film E sublimes, its volume increases rapidly to about 750 times as carbon dioxide. As a result, as shown in Fig. 4(D), the deposit 54 having microcracks 56 is peeled off and blown away, and the deposit 54 is removed from the surface 52. In this way, the glass article 10 is produced.

[0037] (Dry ice blasting conditions) As shown in FIG. 3, in the blasting apparatus 100, the glass intermediate body 50 is placed on a base 104 with the identification information, which is the processed portion 12, facing upward. An injection nozzle 102 is placed above the surface of the glass intermediate body 50 placed on the base 104. The injection nozzle 102 has an injection port 102a that opens downward toward the glass intermediate body 50. Liquefied carbon dioxide gas is supplied to the blasting apparatus 100. The blasting apparatus 100 generates dry ice particles from the liquefied carbon dioxide gas. The generated dry ice particles are supplied to the injection nozzle 102. A carrier gas for injecting the dry ice is further supplied to the injection nozzle 102.

[0038] The blasting device 100 includes a holding unit (not shown) that movably holds the injection nozzle 102. The holding unit has an actuator such as a motor. The blasting device 100 holds the injection nozzle 102 so that it can move parallel to a direction perpendicular to the up-down direction.

[0039] In the blasting device 100, the particle size of the dry ice particles, the collision pressure of the dry ice particles, and the scanning speed of the injection nozzle 102 are adjusted. The particle size of the dry ice is preferably 200 μm or less, more preferably 100 μm or less, particularly preferably 50 μm or less, and preferably 1 μm or more, more preferably 5 μm or more, particularly preferably 10 μm or more. The particle size of the dry ice is measured using a Doppler ultrasonic flowmeter. The collision pressure is the pressure applied to the glass intermediate 50 when the dry ice particles collide with the glass intermediate 50. The scanning speed is the moving speed when the injection nozzle 102 moves in parallel with respect to the glass intermediate 50. In the thermal processing, modification is performed using a femtosecond laser with an average output of 1.8 W, a pulse width of 400 femtoseconds, a repetition frequency of 100 kHz, and a moving speed of 100 mm / s.

[0040] As shown in FIG. 5, an experiment was conducted on the removal of deposits 54 and the decrease in strength of the glass intermediate 50 by changing the collision pressure and the scanning speed. As a result, deposits 54 were removed under conditions other than the sixth condition. Note that deposits 54 remained under the sixth condition, but it was possible to remove more of deposits 54 by setting the scanning speed in the range of 50 to 200 m / s. Also, a decrease in strength of the glass intermediate 50 was observed under the fifth condition, but it was determined that this did not affect the performance of the glass article 10. Note that the strength was evaluated by the ring-on-ring method, and it was determined that there was no decrease in strength when there was no significant difference in a t-test compared to the glass intermediate 50 that had not been subjected to the blasting treatment, and that there was a decrease in strength when there was a significant difference.

[0041] From the above, it was possible to remove deposit 54 while suppressing a decrease in strength that would affect the performance of glass article 10, so long as the collision pressure was 1.5 MPa or more and 50 MPa or less. Furthermore, a good evaluation could be obtained if the particle size of dry ice was 1 μm to 200 μm, and preferably 5 μm to 50 μm. A good evaluation could be obtained if the scanning speed was preferably 300 mm / s or less, and more preferably 5 to 100 mm / s.

[0042] The temperature of the carrier gas is set to a temperature at which condensation does not occur on the glass intermediate 50, and may be, for example, 5 to 30°C.

[0043] In a modified example, the blasting apparatus 100 may move the stage 104 together with the injection nozzle 102 or instead of the injection nozzle 102. In this case, the relative movement speed of the glass intermediate body 50 with respect to the injection nozzle 102 may be the scanning speed.

[0044] The blasting treatment described herein can properly remove deposits 54 even from glass that contains a large amount of components that are likely to cause deposits 54, such as the glass intermediate body 50. Furthermore, the blasting treatment described herein can properly remove deposits 54 even from glass that is caused by thermal processing in which high energy is applied to the glass intermediate body 50 by a femtosecond laser.

[0045] (Second Example) With reference to FIG. 6, differences between the manufacturing method of the glass article 210 of this embodiment and the first embodiment will be described. In this embodiment, the shape of the glass article 210 is different from that of the glass article 10. The glass article 210 has a cylindrical shape. In a modified example, the glass article 210 may have a tubular shape other than a cylindrical shape. The glass article 210 is a borosilicate glass having the same components as the glass article 10.

[0046] (Method of manufacturing glass article) In the manufacturing method of the glass article 210, steps similar to those from S12 to S18 are performed. The heat processing device (not shown) on which the glass intermediate 250 is placed in S12 is a device that performs the face-burning process. In the face-burning process, the end of the glass intermediate 250 is heated to round off the corners of the end. The glass intermediate 250 is made by cutting a cylindrical glass tube extending in the axial direction of a cylindrical shape. Therefore, the end of the glass intermediate 250 after cutting has sharp corners due to the cutting, or the glass intermediate contains cracks due to the cutting. By remelting the glass in the face-burning process in S14, the corners of the end caused by the cutting can be rounded off or the cracks can be eliminated.

[0047] 7, in the end-burning process, a first end of the glass intermediate 250 is heated by a burner 300. The glass intermediate 250 is rotated around the central axis of the cylindrical shape, and the end of the glass intermediate 250 is heated by the burner over the entire length of the end. As a result, deposits 254 similar to those in the first embodiment are formed on the inner circumferential surface of the glass intermediate 250 near the end.

[0048] As shown in FIG. 8, in the removal step of S18, the injection nozzle 310 is disposed toward the inner circumferential surface of the glass intermediate 250. The injection nozzle 310 is the same as the injection nozzle 102. The blasting device includes an actuator that rotates the glass intermediate 250 around the central axis of the cylindrical shape. This allows the dry ice particles to collide with the inner circumferential surface near the end of the glass intermediate 250 at least once. In the removal step, gas is supplied from the second end 250b opposite to the first end 250a where the blasting is being performed, toward the first end 250a where the blasting is being performed, during or after the dry ice blasting. The gas is, for example, air. This allows the deposit 254 peeled off from the glass intermediate 250 by the blasting to be discharged to the outside of the glass intermediate 250. This allows the glass article 210 to be produced.

[0049] In a variant, the blasting device may move the injection nozzle 310 together with the glass intermediate body 250 or in place of the glass intermediate body 250 .

[0050] Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples exemplified above.

[0051] For example, in the manufacturing method of the glass article 10, 210, a preheating step may be performed after the thermal processing step S14, in which at least the periphery of the glass intermediate 50, 250 to which the deposit 54, 254 is attached is heated. This makes it easier to cause thermal shock in the removal step, and makes it easier to cause thermal shrinkage. As a result, the difference in thermal shrinkage between the glass intermediate 50, 250 and the deposit 54, 254 is increased, making it easier to cause cracks in the deposit 54, 254.

[0052] The technical elements described in this specification or drawings have technical utility either alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technologies illustrated in this specification or drawings can achieve multiple objectives simultaneously, and achieving one of these objectives is itself technically useful. [Explanation of symbols]

[0053] 10: glass article, 12: workpiece, 50: glass intermediate body, 52: surface, 54: deposit, 100: blasting device, 102: injection nozzle, 102a: injection port, 104: stand, 210: glass article, 250: glass intermediate body, 250a: first end, 250b: second end, 254: deposit, 310: injection nozzle

Claims

1. A method for manufacturing a glass article, comprising the steps of: A thermal processing step of thermally processing a glass intermediate of the shaped glass article; and a removal step of performing a blasting treatment with dry ice on deposits resulting from a specific component contained in the glass intermediate body due to the thermal processing, thereby removing the deposits from the glass intermediate body.

2. The method for manufacturing a glass article according to claim 1 , wherein the specific component includes at least one component selected from the group consisting of silicon (Si), boron (B), aluminum (Al), sodium (Na) and potassium (K).

3. The glass article comprises, in mass %, B ２ O ３ and R ２ 3. The method for producing a glass article according to claim 1 or 2, wherein R represents lithium (Li), sodium (Na) and potassium (K) and O represents 5% or more in total.

4. The method for producing a glass article according to claim 1 or 2, wherein the thermal processing includes laser processing in which a laser is irradiated onto at least one of a surface and an interior of the glass intermediate body.

5. 3. The method for manufacturing a glass article according to claim 1, wherein the collision pressure of the dry ice in the blasting treatment is 50 MPa or less.

6. The glass article has a plate shape, The method for producing a glass article according to claim 1 or 2, wherein the thermal processing modifies at least one of a surface and an inside of the glass intermediate body by heating.

7. The glass article has a tubular shape; The thermal processing includes a mouth-burning process for heating an end portion of the glass intermediate body, 3. The method for manufacturing a glass article according to claim 1, wherein the blasting treatment comprises ejecting the dry ice from an ejection nozzle from the outside of one end of the glass intermediate toward the deposit that adheres to the inner surface of the glass intermediate by the mouth-burning process.

8. The method for manufacturing a glass article according to claim 7 , wherein, in the blasting treatment, a position of an injection port of the injection nozzle and an inner peripheral surface of the glass intermediate body facing the injection port are changed relatively.

9. The method for manufacturing a glass article according to claim 7 , wherein the removing step includes a process of flowing a gas from a second end portion opposite to the first end portion of the tubular shape toward the first end portion.

Images